METHODS AND KITS FOR DETERMINING CELL SECRETED BIOMOLECULES

20220145355 · 2022-05-12

    Inventors

    Cpc classification

    International classification

    Abstract

    The invention inter alia pertains to methods and kits for analysis of one or more cell released biomolecules. Furthermore, the invention relates to a plurality of sequenceable products comprising different sequence elements. The described technology is useful for a variety of applications, in particular biomolecule analysis applications, e.g. for obtaining biomolecule release profiles of single cells in a multiplexed manner, wherein the cells are provided in a matrix

    Claims

    1. A method for analyzing one or more cell released biomolecules, comprising providing a cell-laden matrix, wherein the cell-laden matrix comprises at least one cell that releases one or more biomolecules of interest, wherein the method comprises the following steps: a) providing a capture matrix, wherein the capture matrix comprises one or more types of capture molecules, wherein each type of capture molecule binds a biomolecule of interest; b) incubating the cell-laden matrix to allow release of the one or more biomolecules of interest and binding the one or more biomolecules of interest to the one or more types of capture molecules of the capture matrix; c) adding one or more types of detection molecules, wherein each type of detection molecule specifically binds a biomolecule of interest, and wherein each type of detection molecule comprises a barcode label which comprises a barcode sequence (B.sub.S) indicating the specificity of the detection molecule; d) generating a sequenceable reaction product which comprises at least (i) the barcode sequence (B.sub.S), and (ii) a barcode sequence (B.sub.T) for indicating a time information, and/or (iii) a barcode sequence (B.sub.P) for indicating a position information, and (iv) optionally a unique molecular identifier (UMI) sequence, wherein generation of the sequenceable reaction product comprises the use of at least one oligonucleotide, optionally a primer, that is capable of hybridizing to the barcode label of the at least one type of detection molecule or the use of at least one oligonucleotide that is ligated to the barcode label of the at least one type of detection molecule.

    2. The method according to claim 1, wherein the sequenceable reaction product comprises a barcode sequence (B.sub.T) for indicating a time information and wherein n cycles of steps a) to c) and optionally step d) are performed at different time points t.sub.x, wherein n is at least 2 and x indicates the different time points, and wherein for each cycle a sequenceable reaction product is generated that differs in its barcode sequence B.sub.T from the barcode sequence B.sub.T of all other performed cycles.

    3. The method according to claim 1 or 2, wherein a plurality of cell-laden matrices and capture matrices are provided in a cell culture device comprising a plurality of compartments, wherein at least one cell-laden matrix and at least one capture matrix are provided within a compartment of the cell culture device.

    4. The method according to claim 3, wherein the method comprises obtaining capture matrices from a plurality of compartments and transfer of the capture matrices to a device comprising a plurality of compartments.

    5. The method according to claim 3 or 4, wherein at least one cycle of steps a) to d) is performed for a plurality of cell-laden matrices comprised in different compartments and wherein the sequenceable reaction product that is generated in step d) comprises a barcode sequence B.sub.P for indicating position information of a cell-laden matrix analysed, wherein a sequenceable reaction product is generated for a cell-laden matrix comprised in a compartment that differs in its barcode sequence B.sub.P from the barcode sequence B.sub.P of the sequenceable reaction product(s) generated for a cell-laden matrix comprised in another compartment.

    6. The method according to claim 5, wherein the barcode sequence B.sub.P is introduced into the sequenceable reaction product via an oligonucleotide that is used in step d), wherein the oligonucleotide comprising the barcode sequence B.sub.P is a primer that is used in an amplification reaction.

    7. The method according to one or more of claims 1 to 6, comprising analyzing y different biomolecules of interest using different types of capture molecules and different types of detection molecules, wherein y is at least 2 and wherein the barcode label of each type of detection molecule that binds a biomolecule of interest differs in its barcode sequence B.sub.S from the barcode sequence B.sub.S of all other types of detection molecules that bind a different biomolecule of interest.

    8. The method according to one or more of claims 1 to 7, wherein step d) comprises performing an amplification reaction using a primer or primer combination, optionally wherein step d) additionally comprises extending the barcode label using an adaptor barcode oligonucleotide capable of hybridizing to the barcode label as template, whereby an extended barcode label is provided in advance of the amplification reaction.

    9. The method according to one or more of claims 1 to 8, wherein the method comprises e) sequencing the generated sequenceable reaction product(s), optionally wherein the method comprises pooling sequenceable reaction products generated in step d) from different cycles and/or generated from different compartments and sequencing the obtained pool.

    10. The method according to one or more of claims 1 to 9, wherein step d) comprises (aa) hybridizing at least one oligonucleotide to the barcode label of at least one type of detection molecule and extending said barcode label using the hybridized oligonucleotide as template thereby obtaining an extended barcode label attached to the detection molecule that additionally comprises sequence information of the hybridized oligonucleotide that was used as template, optionally wherein step d) further comprises (bb) performing an amplification reaction with a primer or primer combination using the extended barcode label and/or the reverse complement thereof as template, wherein preferably, the extended barcode label is used as template.

    11. The method according to one or more of claims 1 to 10, wherein generation of the sequenceable reaction product in step d) comprises the use of (i) at least one oligonucleotide, optionally a primer, and/or (ii) a primer combination, wherein the at least one oligonucleotide and/or the primer combination includes one or more sequence elements selected from the group consisting of a barcode sequence (B.sub.T) for indicating a time information, a barcode sequence (B.sub.P) for indicating position information of a cell-laden matrix, a unique molecular identifier (UMI) sequence, optionally wherein the UMI sequence has a length of up to 40 nucleotides, preferably 4-20 nucleotides, and an adapter sequence (AS) for sequencing, wherein the one or more sequence elements B.sub.T, B.sub.P, UMI and/or AS, if included, are located 5′ of the sequence region of the oligonucleotide and/or primer that is capable of hybridizing to the barcode label of the detection molecule or the reverse complement thereof.

    12. The method according to one or more of claims 1 to 11, wherein the barcode label attached to a detection molecule and/or the extended barcode label obtained according the method of claim 9 to 11 comprises (i) the barcode sequence (B.sub.S) indicating the specificity of the detection molecule; (ii) one or more primer target sequences; (iii) optionally a barcode sequence (B.sub.T) indicating a time information; (iv) optionally a unique molecular identifier (UMI) sequence; and (v) optionally an adapter sequence (1).

    13. The method according to one or more of claims 1 to 12, wherein step d) comprises per Variant A (aa) adding an adaptor barcode oligonucleotide capable of hybridizing to the barcode label of at least one type of detection molecule, wherein the adaptor barcode oligonucleotide comprises 5′ to the region that is capable of hybridizing to the barcode label a unique molecular identifier (UMI) sequence, and extending the barcode label using the hybridized adaptor barcode oligonucleotide as template thereby obtaining an extended barcode label; wherein preferably step d) further comprises (bb) performing an amplification reaction with a primer or primer combination using the extended barcode label and/or the reverse complement thereof as template; or per Variant B (aa) adding an adaptor barcode oligonucleotide capable of hybridizing to the barcode label of at least one type of detection molecule, wherein the adaptor barcode oligonucleotide comprises 5′ to the region that is capable of hybridizing to the barcode label (i) a barcode sequence (B.sub.P) for indicating a position information and (ii) preferably a unique molecular identifier (UMI) sequence, and extending the barcode label using the hybridized adaptor barcode oligonucleotide as template thereby obtaining an extended barcode label; wherein preferably, step d) further comprises (bb) performing an amplification reaction with a primer or primer combination using the extended barcode label and/or the reverse complement thereof as template; or per Variant C (aa) adding an adaptor barcode oligonucleotide capable of hybridizing to the barcode label of at least one type of detection molecule, wherein the adaptor barcode oligonucleotide comprises 5′ to the region that is capable of hybridizing to the barcode label (i) a barcode sequence (B.sub.T) for indicating a time information and/or (ii) a unique molecular identifier (UMI) sequence, and extending the barcode label using the hybridized adaptor barcode oligonucleotide as template thereby obtaining an extended barcode label; wherein preferably step d) further comprises (bb) performing an amplification reaction with a primer or primer combination using the extended barcode label and/or the reverse complement thereof as template.

    14. The method according to any one of claims 1 to 13, wherein step d) comprises (aa) adding an adaptor barcode oligonucleotide, wherein the adaptor barcode oligonucleotide comprises an adaptor sequence (1).sub.R that is reverse complementary to an adapter sequence (1) of the barcode label of the detection molecule, wherein the adaptor barcode oligonucleotide additionally comprises at least one, at least two, at least three or all sequence elements selected from the group consisting of a barcode sequence (B.sub.T) for indicating a time information, a barcode sequence (B.sub.P) for indicating a position information, a unique molecular identifier (UMI) sequence, and a primer target sequence, wherein these one or more sequence elements are located 5′ of the adaptor sequence (1).sub.R and extending the barcode label using the hybridized adaptor barcode oligonucleotide as template thereby obtaining an extended barcode label.

    15. The method according to claim 9 to 14, wherein step d) comprises performing an amplification reaction with a primer or primer combination comprising a barcode sequence (B.sub.P) for indicating position information, optionally an adapter sequence (AS) for sequencing, optionally a barcode sequence (B.sub.T) for indicating a time information, wherein the one or more sequence elements B.sub.P, AS, and/or B.sub.T if included in the primer or a primer of the primer combination, are located 5′ of the sequence region of the primer that is capable of hybridizing to the optionally extended barcode label or the reverse complement thereof.

    16. The method according to claim 15, wherein the templates comprised in different compartments of a device are contacted with a different subtype of the primer or primer combination, wherein the different subtypes of the primer or primer combination differ in their barcode sequence B.sub.P that indicates the position information of an individual compartment, wherein preferably, the subtypes of the primer or primer combination are identical except for the barcode sequence B.sub.P that is unique for each subtype.

    17. The method according to claim 16, wherein the amplification in step d) is performed by contacting the templates comprised in different compartments of a device with different primer combinations, wherein one primer of the primer combination is the same for all templates comprised in different compartments of the device and the other primer of the primer combination differs in the barcode sequence B.sub.P that indicates the position information of an individual compartment.

    18. The method according to one or more of claims 1 to 17, wherein the barcode sequence B.sub.T is provided in the barcode label or the extended barcode label and wherein step d) comprises pooling barcode labels or extended barcode labels provided at different time points and comprising different barcode sequences B.sub.T in a compartment prior to performing an amplification reaction.

    19. The method according to one or more of claims 1 to 18, having one or more of the following features a. the matrix comprising at least one cell has one or more of the following characteristics: (i) the matrix material is provided by a hydrogel; (ii) the matrix is three-dimensional; (iii) the matrix is a particle, optionally a hemi-spherical particle or preferably a spherical particle; (iv) the matrix has a diameter of ≤1000 μm, such as ≤800 μm, ≤600 μm, or ≤400 μm, preferably ≤200 μm, such as 5 μm to 150 μm; and/or (vi) the matrix has a volume of ≤200 μl, such as ≤100 μl, ≤50 μl, ≤10 μl, ≤1 μl, ≤0.5 μl, ≤300 nl, <200 nl, ≤100 nl, <50 nl or ≤5 nl, preferably 0.05 pl to 2000 pl; b. the capture matrix comprising the one or more types of capture molecules has one or more of the following characteristics: (i) it is a polymer matrix, optionally comprising or consisting of polyacrylamide (PMA), polyactic acid (PLA), poly(vinyl alcohol) (PVA), polyethylene glycol (PEG), polyoxazoline (POx), and polystyrene (PS). (ii) the matrix material is provided by a hydrogel; (iii) the matrix is three-dimensional; (iv) the matrix is a particle, preferably a spherical particle; and/or (v) the matrix has a diameter of ≤1000 μm, such as ≤800 μm, ≤600 μm or ≤400 μm, preferably ≤200 μm, such as 5 μm to 150 μm; and/or c. the cell-laden matrix and the capture matrix are provided in proximity within a compartment of a device or the cell-laden matrix and the capture matrix are provided in separate compartments, wherein the separate compartments are in fluid communication with each other or can be brought in fluid communication with each other so that the released biomolecules of interest can contact the capture matrix.

    20. The method according to one or more of claims 1 to 19, wherein the matrix of the cell-laden matrix is a hydrogel which has one or more of the following characteristics: a. the hydrogel comprises cross-linked hydrogel precursor molecules of the same type or of different types; b. the hydrogel is composed of at least two different polymers with different structures as hydrogel precursor molecules, wherein optionally, at least one polymer is a copolymer; c. the hydrogel is formed using at least one polymer which has a linear structure and at least one polymer which has a multiarm or star-shaped structure; d. the hydrogel is formed using a t least one polymer of formula (P1) ##STR00004## wherein R is independently selected from a hydrogen atom, a hydrocarbon with 1-18 carbonatoms (preferably CH.sub.3, —C.sub.2H.sub.5,), a C.sub.1-C.sub.25-hydrocarbon with at least one hydroxy group, a C.sub.1-C.sub.25-hydrocarbon with at least one carboxy group, (C.sub.2-C.sub.6)alkylthiol, (C.sub.2-C.sub.6)alkylamine, protected (C.sub.2-C.sub.6)alkylamine (preferably-(CH.sub.2).sub.2-6—NH—CO—R (with R=tert-Butyl, perfluoroalkyl)), (C.sub.2-C.sub.6)alkylazide, polyethylene glycol, polylactic acid, polyglycolic acid, polyoxazoline, or wherein R is a residue R.sup.4 Y is a moiety containing at least one graft, comprising at least one residue R.sup.4, T.sub.1 is a terminating moiety, which may contain a residue R.sup.4, T.sub.2 is a terminating moiety, which contains a residue R.sup.4, p is an integer from 1 to 10, n is an integer greater than 1 and preferably, below 500, m is zero or an integer of at least, preferably greater than 1, and preferably, below 500, the sum n+m is greater than 10, x is independently 1, 2 or 3, preferably x is independently 1 or 2, most preferably x is 1, R.sup.4 independently comprise at least one functional group for crosslinking and/or for binding biologically active compounds, and optionally comprising a (preferably degradable) spacer moiety connecting said functional group with the binding site to the respective moiety of the structure of formula (P1), wherein the entirety of all m-fold and n-fold repeating units are distributed in any order within the polymer chain and wherein optionally, the polymer is a random copolymer or a block copolymer.

    21. The method according to one or more of claims 1 to 20, wherein the method is performed by utilizing a cell culture device, which preferably is a microfabricated cell culture device, wherein the device has one or more of the following features: i) at least one compartment for accommodating at least one, preferably at least two matrices, including at least one capture matrix and/or at least one cell-laden matrix; ii) at least one compartment that is capable of being switched between an isolated and an open state, wherein the isolated state corresponds to a state at which fluid that is present in the compartment is in no contact with fluid not present in the compartment and wherein the open state corresponds to a state at which fluid that is present in the compartment is in contact with fluid not present in the compartment; iii) a compartment for accommodating at least one matrix, preferably two matrices, wherein a microfabricated geometry for matrix immobilization is present suitable for positioning the at least one matrix; iv) a plurality of compartments for accommodating at least one matrix, preferably provided by an array of compartments; v) a microfabricated valve capable of switching the compartment to an open or closed state; vi) a microfabricated valve, comprising a first channel, a second channel, a connection channel connecting the first channel and the second channel, a valve portion arranged within the connection channel, wherein the valve portion is adapted to selectively open and close the connection channel; vii) a microfabricated valve comprising at least three layers, wherein a first channel is located within a first layer; a second channel is located within a third layer; a valve portion is located within a second layer; the second layer is arranged between the first and the third layer; viii) a microfabricated valve wherein a first channel comprises a microfabricated geometry for matrix immobilization suitable for positioning at least one matrix being contained in a fluid which flows through the first channel, wherein the microfabricated geometry for matrix immobilization is arranged within the first channel in such a way that a fluid flow can be reduced by the microfabricated geometry for matrix immobilization, in particular, the microfabricated geometry for matrix immobilization narrows the cross section of the channel; and/or wherein a second channel comprises a microfabricated geometry for matrix immobilization suitable for positioning particles being contained in a fluid which flows through the second channel, wherein the microfabricated geometry for matrix immobilization is arranged within the second channel in such a way that a fluid flow can be reduced by the microfabricated geometry for matrix immobilization, in particular, the microfabricated geometry for matrix immobilization narrows the cross section of the channel; and/or ix) a fluid reservoir and fluid channels for providing fluid to the compartment.

    22. The method according to one or more of claims 1 to 21, wherein the method is performed by utilizing a cell culture device, which preferably is a microfabricated cell culture device, wherein the device comprises one or more of the following features: i) at least one matrix is releasably positioned by a preferably microfabricated geometry for matrix immobilization inside a compartment; ii) at least one matrix is releasably positioned by a preferably microfabricated geometry for matrix immobilization inside a compartment, wherein the geometry for matrix immobilization has one or more of the following characteristics: it is capable of positioning the cell-laden matrix and the capture matrix in proximity; it is capable of positioning at least two cell-laden matrix and the capture matrix in proximity; iii) at least one cell-laden matrix and at least one capture matrix are positioned by a preferably microfabricated geometry for matrix immobilization inside a compartment, wherein the compartment accommodating the at least one cell-laden matrix is different from the compartment accommodating the at least one capture matrix and wherein both compartments can be switched to be either in fluid contact with other or to be in no fluid contact with each other; and/or iv) it comprises a trapping geometry comprising a valve arrangement adapted to provide a fluid passing through a microfabricated geometry for matrix immobilization wherein the valve arrangement is adapted to selectively change the direction of fluid passing the microfabricated geometry for matrix immobilization, in particular wherein a fluid a first direction urging the at least one matrix into the microfabricated geometry for matrix immobilization and a fluid in the second direction urging the at least one matrix out of the microfabricated geometry for matrix immobilization, and in particular fluid in the second direction delivering the at least one matrix in direction of an exit section.

    23. The method according to one or more of claims 1 to 22, wherein the provided cell-laden matrix and capture matrix are provided with a fluid, preferably a fluid that is immiscible with water, wherein said matrices, provided with said fluid, are preferably generated by utilizing a cell culture device, which preferably is a microfabricated cell culture device, and preferably by (i) releasably positioning the cell-laden matrix and the capture matrix by a preferably microfabricated geometry for matrix immobilization inside a compartment, wherein the compartment comprises a first fluid, preferably an aqueous fluid; (ii) removing the first fluid from the compartment and replacing the first fluid by a second fluid that provides said fluid, wherein said fluid is preferably immiscible with water; and (iii) optionally, removing the second fluid from the compartment and replacing it by the first fluid or a third fluid, that is preferably immiscible with the second fluid.

    24. The method according to one or more of claims 1 to 23, wherein the cell-laden matrix is incubated to allow release of one or more biomolecules of interest before providing the capture matrix in step a), wherein after providing the capture matrix, one or more biomolecules of interest are specifically bound by the one or more types of capture molecules of the capture matrix; wherein preferably, the cell-laden matrix is provided in a defined volume of a fluid, preferably a fluid that is immiscible with water, and wherein the capture matrix is provided in a defined volume of the same type of fluid, and wherein after contacting the cell-laden matrix and the capture matrix said fluids of the same type merge to provide a defined volume of fluid that is shared by the cell-laden matrix and the capture matrix.

    25. A kit comprising a) one or more types of detection molecules, wherein each type of detection molecule specifically binds a biomolecule of interest, and wherein each type of detection molecule comprises a barcode label which comprises a barcode sequence (B.sub.S) indicating the specificity of the detection molecule; and b) at least one oligonucleotide, optionally a primer, that is preferably capable of hybridizing to the barcode label of the at least one type of detection molecule.

    26. The kit according to claim 25, wherein the oligonucleotide comprises at least one sequence element selected from the group consisting of (i) a barcode sequence (B.sub.T) for indicating a time information, (ii) a barcode sequence (B.sub.P) for indicating a position information, and (iii) a unique molecular identifier (UMI) sequence.

    27. The kit according to claim 25 or 26, wherein the kit has one or more of the following characteristics: a. it comprises an adaptor barcode oligonucleotide capable of hybridizing to the barcode label of at least one type of detection molecule, wherein the adaptor barcode oligonucleotide comprises 5′ to the region that is capable of hybridizing to the barcode label (i) a barcode sequence (B.sub.T) for indicating a time information, a barcode sequence (B.sub.P) for indicating a position information, and/or (ii) a unique molecular identifier (UMI) sequence; b. it comprises an adaptor barcode oligonucleotide, wherein the adaptor barcode oligonucleotide comprises an adaptor sequence (1).sub.R that is reverse complementary to an adapter sequence (1) of the barcode label of the detection molecule, wherein the adaptor barcode oligonucleotide additionally comprises at least one, at least two, at least three or all sequence elements selected from the group consisting of a barcode sequence (B.sub.T) for indicating a time information, a barcode sequence (B.sub.P) for indicating a position information, a unique molecular identifier (UMI) sequence, and a primer target sequence, wherein these one or more sequence elements are located 5′ of the adaptor sequence (1).sub.R; c. a primer or primer combination comprising one or more of the following a barcode sequence (B.sub.P) for indicating position information, a barcode sequence (B.sub.T) for indicating a time information, an adapter sequence (AS) for sequencing, wherein the one or more sequence elements B.sub.P, AS, and/or B.sub.T if included in the primer or a primer of the primer combination, are located 5′ of the sequence region of the primer that is capable of hybridizing to the optionally extended barcode label or the reverse complement thereof; and/or d. the barcode label of the one or more types of detection molecules comprises (i) the barcode sequence (B.sub.S) indicating the specificity of the detection molecule; (ii) one or more primer target sequences; (iii) optionally a barcode sequence (B.sub.T) indicating a time information; (iv) optionally a unique molecular identifier (UMI) sequence; and (v) optionally an adapter sequence (1).

    28. The kit according to any one of claims 25 to 27, wherein the kit comprises at least one set of oligonucleotides selected from the following group: a) set 1 comprising: a. a barcode label attached to the detection molecule comprising: i. optionally a cleavable linker/spacer, ii. optionally a first primer binding sequence (1), iii. a barcode sequence B.sub.S, iv. an adaptor sequence (1); b. an adaptor barcode oligonucleotide comprising: i. an adaptor sequence (1).sub.R, ii. a unique molecular identifier (UMI) sequence, iii. a second primer binding sequence (2).sub.R, c. a forward primer comprising: i. a primer sequence (1), ii. a barcode sequence B.sub.P, iii. an adaptor sequence for sequencing (AS); d. a reverse primer comprising: i. a primer sequence (2).sub.R, ii. a barcode sequence B.sub.T, iii. an adaptor sequence for sequencing (AS); b) set 2 comprising: a. a barcode label attached to the detection molecule comprising: i. optionally a cleavable linker/spacer, ii. a first primer binding sequence (1), iii. a barcode sequence B.sub.S, iv. an adaptor sequence (1); b. an adaptor barcode oligonucleotide comprising: i. an adaptor sequence (1).sub.R, ii. a barcode sequence B.sub.P, iii. a unique molecular identifier (UMI) sequence, iv. a second primer binding sequence (2).sub.R; c. a forward primer comprising: i. a primer sequence (1), ii. a barcode sequence B.sub.T, iii. an adaptor sequence for sequencing (AS); d. a reverse primer comprising: i. a primer sequence (2).sub.R, ii. an adaptor sequence for sequencing (AS); c) set 3 comprising: a. a barcode label attached to the detection molecule comprising: i. optionally a cleavable linker/spacer, ii. a first primer binding sequence (1), iii. a barcode sequence B.sub.S, iv. an adaptor sequence (1); b. an adaptor barcode oligonucleotide comprising: i. an adaptor sequence (1).sub.R, ii. a barcode sequence B.sub.T, iii. a unique molecular identifier (UMI) sequence, iv. a second primer binding sequence (2).sub.R; c. a forward primer comprising: i. a primer sequence (1), ii. a barcode sequence B.sub.P, iii. an adaptor sequence for sequencing (AS); d. a reverse primer comprising: i. a primer sequence (2).sub.R, ii. an adaptor sequence for sequencing (AS); d) set 4 comprises: a. a barcode label attached to the detection molecule comprising: i. optionally a cleavable linker/spacer, ii. a first primer binding sequence (1), iii. a barcode sequence B.sub.S, iv. a unique molecular identifier (UMI) sequence, v. a barcode sequence B.sub.T, vi. a second primer binding sequence (2); b. a forward primer comprising: i. a primer sequence (1), ii. a barcode sequence B.sub.P, iii. an adaptor sequence for sequencing (AS); c. a reverse primer comprising: i. a primer sequence (2).sub.R, ii. an adaptor sequence for sequencing (AS).

    29. The kit according to any one of claims 25 to 28, wherein the kit comprises at least one of the following a. one or more types of capture molecules, wherein each type of capture molecule binds a biomolecule of interest, wherein preferably, the one or more types of capture molecules provided in the kit bind the same biomolecules of interest as the one or more types of detection molecules comprised in the kit; b. one or more polymers for providing the matrix for the cells and/or the capture matrix, wherein preferably the polymer is capable of forming a hydrogel; c. a composition, preferably a solution, containing capture matrices; d. polymerase and/or dNTPs; and/or e. a wash solution.

    30. The kit according to any one of claims 25 to 29, wherein the kit comprises a device with a plurality of compartments, preferably a multi-well plate, wherein said device has one or more of the following characteristics: a. compartments of the device comprise an oligonucleotide, preferably an adaptor barcode oligonucleotide and/or a primer or primer combination, as defined in claims 25 to 29; b. compartments of the device comprise at least one set as defined in claim 28; c. compartments comprising an oligonucleotide, preferably an adaptor barcode oligonucleotide and/or a primer or primer combination, as defined in any one of claims 25 to 29, furthermore comprise reagents for performing an extension and/or amplification reaction; and/or d. the device is selected from a 96, 384 or 1536 well plate.

    31. A plurality of sequenceable products, wherein each sequenceable product comprises at least the following sequence elements (i) a barcode sequence (B.sub.S) for indicating a specificity, and (ii) a barcode sequence (B.sub.T) for indicating a time information, and/or (iii) a barcode sequence (B.sub.P) for indicating a position information, and (iv) optionally a unique molecular identifier (UMI) sequence.

    32. The plurality sequenceable products according to claim 31, wherein the sequenceable products differ from each other in one or more of the comprised sequence elements (i) to (iv).

    33. The plurality of sequenceable products as defined in claim 31 or 32, having one or more of the following features: a. the number of sequenceable products comprising different sequence elements B.sub.S, B.sub.T and/or B.sub.P is at least 50, preferably at least 100; b. the plurality of sequenceable products comprise at least 2 different barcode sequences B.sub.S, optionally wherein the number of different barcode sequences B.sub.S may lie in a range of 2 to 100, 5 to 50, 5 to 25, 5 to 20 or 7 to 15; c. the plurality of sequenceable products comprise at least 2 different barcode sequences B.sub.T, optionally wherein the number of different barcode sequences B.sub.T may lie in a range of 2 to 200, 5 to 50, 5 to 25, 5 to 20 or 7 to 15; and d. the plurality of sequenceable products comprise at least 2 different barcode sequences B.sub.P, optionally wherein the number of different barcode sequences B.sub.P may lie in a range of 2 to 1000, 5 to 1000, 10 to 500, 20 to 250 or 50 to 200; and/or e. wherein the UMI sequence has a length of up to 40 nucleotides, preferably 4 to 20 nucleotides.

    34. The method according to one or more of claims 1-20, wherein the cell-laden matrix is provided in a compartment of a cell culture plate such that liquid that covers the cell-laden matrix can be removed or exchanged without affecting the cell-laden matrix, and wherein the cell-laden matrix comprises more than one cell and is provided by a three-dimensional hydrogel matrix, optionally having at least partially an ellipsoidal shape, preferably a plug or semi-sphere shape.

    35. The method according to claim 34, wherein one or more capture matrices are provided in step a), the method having one or both of the following characteristics: incubating the cell-laden matrix to allow release of one or more biomolecules of interest before adding the provided capture matrix/matrices to the compartment of the cell culture plate to bind the one or more released biomolecules of interest to the one or more types of capture molecules of the capture matrix, wherein optionally incubating is performed for an incubation period selected from 1 h to 72 h; and/or the capture matrix is transferred to another compartment after binding the one or more biomolecules of interest to the one or more types of capture molecules of the capture matrix in step b).

    36. The method according to one or more of claims 1-20 or 34-35, wherein biomolecules are analyzed time-dependently, wherein the time interval between analyses is selected from ≥10 min, ≥20 min, ≥30 min, ≥1 h, ≥2 h, ≥3 h, ≥4 h, 5 h or more, up to days 1 d, 2 d or several days, preferably selected from the range of 30-120 min.

    Description

    DETAILED DESCRIPTION OF EMBODIMENTS ILLUSTRATED IN THE FIGURES

    [0613] FIG. 1: FIG. 1 shows a microfluidic array 30 having a plurality of compartments (e.g. observation chambers 32), such a compartment 32m2n2 at position m2 n2, each loaded with (single) cell-laden matrix under perfusion culture. Depicted are the rows n and columns m of the array as well as corresponding compartments. Lines representing rows and columns are illustrating pressure lines for providing common group commands as is described herein. Circles illustrate individual compartments. Each compartment may contain at least one cell-laden matrix which can have defined characteristics. The matrix containing at least one cell may be provided by a hydrogel with defined characteristics (e.g. elasticity, immobilized ECM proteins and/or peptides, in particular RGD sites, fibronectin, YIGSR peptides, collagen, LDV peptides, laminin). The matrix preferably has a spherical form and may be provided by a hydrogel bead that contains at least one cell (e.g. an immune cell, a cancer cell, a stem cell).

    [0614] FIG. 2A: Illustrates core steps of the method of the invention according to one embodiment:

    [0615] As illustrated in A, a cell-laden matrix (1), which preferably is a hydrogel bead, and a capture matrix (2), which preferably is a hydrogel bead, are positioned in close proximity within an isolated compartment at a position X|Y of a device, which according to a preferred embodiment is a microfabricated cell culture device. The cell-laden matrix comprises in the illustrated embodiment a single cell (3), which secretes two biomolecules of interest (4a and 4b). The capture matrix (2) comprises in the illustrated embodiment two different types of capture molecules (5a and 5b), which specifically bind the biomolecules of interest (4a and 4b). The different types of capture molecules are in the illustrated embodiment provided by antibodies with different specificities against the secreted biomolecules of interest. The capture matrix preferably comprises a plurality of capture molecules of the same type to ensure efficient capture of a biomolecule of interest. The capture molecules may be provided in excess of the expected number of secreted biomolecule of interest.

    [0616] In B, the cell-laden matrix (1) is incubated to allow sufficient secretion of the biomolecules of interest which diffuse from the cell-laden matrix (1) to the capture matrix (2), where a biomolecule of interest is bound by the matching type of capture molecule (see interaction pairs 4a/5a and 4b/5b). Unbound molecules may be washed away.

    [0617] In C, one or more types of detection molecules are added, here two types of detection molecules (6a and 6b), wherein each type of detection molecule specifically binds a biomolecule of interest. Importantly, each type of detection molecule comprises a barcode label (7) which comprises a barcode sequence (B.sub.S) indicating the specificity of the detection molecule. Thus, the specificity of the capture molecule can be determined based on the barcode label. The barcode label may be provided by an oligonucleotide sequence that may be attached via a linker to the detection molecule. In an embodiment, the linker is provided by a photocleavable spacer. In the illustrated embodiment the different types of detection molecules are provided by antibodies which bind the biomolecule of interest at a different epitope than the antibodies used for capturing. Thereby, a complex is formed, comprising the capture molecule, the biomolecule of interest and the detection molecule (see complex 4a/5a/6a and 4b/5b/6b).

    [0618] In D, a sequenceable reaction product is generated which comprises at least (i) the barcode sequence (B.sub.S), and (ii) a barcode sequence (B.sub.T) for indicating a time information, and/or (iii) a barcode sequence (B.sub.P) for indicating position information of the cell-laden matrix, and (iv) optionally a unique molecular identifier (UMI) sequence. The generation of the sequenceable reaction product comprises the use of at least one oligonucleotide, which in one embodiment is a primer, that is capable of hybridizing to the barcode label of the at least one type of detection molecule. As is described herein and also illustrated in the subsequent figures, step D may comprise several substeps, including transfer steps.

    [0619] One embodiment of step D that is schematically illustrated in FIG. 2 comprises a step (aa), which is as described herein an optional, but in some embodiments a preferred step. Step (aa) comprises hybridizing an oligonucleotide (8) to the barcode label of the detection molecules and extending said barcode label by a polymerase reaction using the hybridized oligonucleotide as template, whereby an extended barcode label is obtained that remains attached to the detection molecule. The extended barcode label additionally comprises the sequence information of the hybridized oligonucleotide that was used as template. The oligonucleotide (in embodiments also referred to as adaptor barcode oligonucleotide) may comprise in embodiments explained in further detail below a barcode sequence (B.sub.T) for indicating a time information (i.e. the current time point where the oligonucleotide is added) and/or a unique molecular identifier (UMI) sequence. Extension of the barcode label by a polymerase using the oligonucleotide as template transfers the barcode sequence (B.sub.T) for indicating a time information and/or the UMI information from the oligonucleotide to the extended barcode label. As is illustrated in FIG. 2, the hybridized oligonucleotide may also be extended, whereby a double-stranded molecule (9) is generated. However, it is also within the scope of the present invention to use an oligonucleotide comprising a blocked 3-OH end that cannot be extended by a polymerase.

    [0620] The capture matrix with the detection molecules, that comprise the barcode labels, which were optionally extended as described above in step D (aa), may be obtained from the compartment and can be transferred to a pre-defined compartment, such as a pre-defined well, of a different device. The transfer may occur using the RFCP-mechanism that is described elsewhere herein. The capture matrix with the (optionally extended) barcode labels may be e.g. transferred into a well of another format such as a 96-well plate. In embodiments, the transfer of the capture matrix occurs prior to step D, e.g. after capturing the biomolecules of interest in step B and/or after binding the detection molecules in step C. The removal of the capture matrix which comprises the complexes comprising the capture molecule, the biomolecule of interest and the detection molecule from the compartment leaves the cell-laden matrix in the compartment. As is illustrated in F, a “fresh” capture matrix may be added/loaded into the compartment and a new cycle may be performed at a different time-point. The steps may be repeated at several time-points.

    [0621] Preferably, D comprises performing an amplification reaction using a primer or primer combination. In the illustrated embodiment, such amplification reaction is performed after performing step D (aa). The amplification reaction is indicated in FIG. 2 as D (bb) and comprises performing an amplification reaction with a primer or primer combination using the extended barcode label and/or the reverse complement thereof as template. Preferably, the extended barcode label is used as template (the reverse complement thereof may be removed as described elsewhere herein in case a double-stranded molecule is formed during the extension step that includes the reverse complement of the barcode label and/or an oligonucleotide with a blocked 3′-OH end may be used to prevent that a reverse complement strand of the barcode label is formed in the extension reaction). If a single primer is used, a linear amplification can be performed by performing several amplification cycles. The use of a primer combination such as a primer pair allows to perform a PCR reaction. The primer or primer combination as well as the additional components required for performing the amplification reaction (such as a polymerase, dNTPs, buffers) may be added to the compartments (e.g. wells) that comprise the transferred capture matrix or may be provided in advance. The primer or primer combination may comprise a barcode sequence (B.sub.P) for indicating position information and optionally an adapter sequence (AS) for sequencing, e.g. a standard adapter for a sequencing platform. Further embodiments are illustrated in the subsequent figures. The primer or primer combination can hybridize to the optionally extended barcode label or the reverse complement thereof. As is described herein, the optionally extended barcode label may be released from the detection molecule in advance of the amplification reaction, e.g. when a photocleavable linker is used.

    [0622] The amplification products may then be sequenced in step E. As is described herein, the method according to the present invention provides multiple pooling options, allowing to make the sequencing very cost and time efficient.

    [0623] FIG. 2B illustrates examples of well positions in a well plate, into which the capture matrices can be transferred for performing the amplification reaction. As is described herein, the initial cell culture device may comprise several compartments for receiving a cell-laden matrix and a capture matrix. If the cell culture device comprises e.g. 100 compartments (cultivation positions for different cell-laden matrices) and 10 different types of capture molecules are used in combination with 10 different types of corresponding detection molecules to capture and detect the biomolecules of interest at 10 different time-points, 100 wells are required. As is shown in FIG. 2B, it is within the scope of the present invention to pool e.g. the capture matrices obtained from the same isolated compartment at time-points 1-10 (or the optionally extended barcode labels that are detached from the detection molecules) into a single well before performing the amplification reaction. This allows to amplify the optionally extended barcode labels obtained at the different timepoints 1-10 in a single amplification reaction. This is time and cost efficient. Moreover, as is described herein, the present method allows to introduce a barcode sequence B.sub.P into the sequenceable reaction product. Thus, all sequenceable reaction products obtained at the different time-points comprise the same barcode sequence B.sub.P, as these originate from the same cell-laden matrix comprised in an individual compartment. The barcode sequence B.sub.P thereby allows to correlate the obtained sequenceable reaction products with the original compartment, respectively the comprised cell-laden matrix. E.g. the transfer of the capture matrix from the compartment of the cell culture device into the well of the device wherein the amplification is performed may be performed such that it allows to correlate the barcode sequence B.sub.P with the original compartment of the in the cell culture device. As all sequenceable reaction products originating from the same compartment, respectively the same cell-laden matrix comprise the same barcode sequence B.sub.P, their origin can be determined based on the barcode sequence B.sub.P. This allows to pool all reaction products obtained after the amplification reaction in the different wells into a single pool/library that is then subsequently sequenced, preferably by NGS sequencing. Thus, the reaction products from all wells can be pooled and send for sequencing.

    [0624] FIG. 2C illustrates an advantageous variation of the method illustrated in FIG. 2A. In the shown embodiment, the transfer of the capture matrix occurs after step C (i.e. after capturing the biomolecules of interest in step B and after binding of the detection molecules in step C) and prior to step D. At least one capture matrix that has captured the biomolecules of interest from at least one cell-laden matrix comprised in a compartment is transferred into a compartment of another device, such as a multi-well plate (e.g. a 96, 384 or 1536-well plate). According to one embodiment, exactly one capture matrix is transferred. The further capture matrix processing may be performed within this well. An UMI sequence may be introduced within said well using an adaptor barcode oligonucleotide comprising an UMI sequence. Thus, as only one capture matrix (or at least two capture matrices comprising the biomolecules of interest released from the same cell-laden matrix comprised in a compartment) is located within one processing/collection well, the required number of different UMIs (corresponds to the UMI library size) is significantly reduced and is limited to the maximum number of detection molecules that can be located within a capture matrix. This number corresponds to the maximum binding capacity of the used capture matrices. As the generation of large UMI libraries is costly, the reduction of the UMI library size results in a significant cost reduction. According to one embodiment, the further processing is performed as is disclosed and illustrated in FIG. 8a. According to a further preferred embodiment, the adaptor barcode oligonucleotide comprises an UMI sequence, while a barcode sequence B.sub.T and a barcode sequence B.sub.P is introduced during amplification using a primer or primer combination, wherein preferably, a primer combination is used wherein one primer comprises the barcode sequence B.sub.T, while the other primer comprises the barcode sequence B.sub.P. This embodiment is advantageous as it allows to provide the reagents and in particular the adaptor barcode oligonucleotides and the primer or primer combination pre-loaded (e.g. in lyophilized form) in the compartments (e.g. wells) of the device into which the capture matrices are transferred. The transfer occurs while maintaining/correlating the position information with the cell-laden matrices comprised in the cell culture device, so that the finally obtained results can be assigned to a cell-laden matrix, respectively the one or more cells comprised therein.

    [0625] FIG. 2D illustrates examples of well positions in a well plate according to the illustration in FIG. 2C, into which the capture matrices are transferred after C. As each well contains only one capture matrix (or at least two capture matrices that have captured the biomolecules of interest from the same cell-laden matrix or two or more cell-laden matrices comprised in the same cultivation compartment), the required number of wells is n×m×k, with n being the column and m the rows of a cell culture device and k being the number of different time points at which the biomolecules of interest were captured. For example, if a microfabricated cell culture device contains 96 cell culture chambers and the secretion profiles are measured at 16 time points or 16 time intervals, an exemplary 1536 plate could be used for performing the capture matrix processing.

    [0626] FIG. 3 schematically illustrates core elements of the sequenceable reaction product that is generated in step d):

    [0627] A: Illustrates a schematic scaffold structure of the core elements. The sequenceable reaction product comprises:

    [0628] (i) the barcode sequence (B.sub.S) for indicating the specificity of the detection molecule (specificity information); and

    [0629] (ii) a barcode sequence (B.sub.T) for indicating a time information (e.g. time-point) in which certain biomolecules of interest have been secreted/detected (time information); and/or

    [0630] (iii) a barcode sequence (B.sub.P) for indicating a position information; and

    [0631] (iv) optionally a unique molecular identifier (UMI) sequence, for quantifying the number of detection molecules that have bound a biomolecule of interest (information about quantity); and

    [0632] (v) optionally an adapter sequence (AS) for sequencing.

    [0633] As is also apparent from the illustrated embodiments, the order of the barcode sequences in the sequenceable reaction product may vary. Furthermore, additional sequence stretches (illustrated by white boxes) may or may not be present between the different barcode sequences/sequence elements.

    [0634] B: The shown sequenceable reaction product can be obtained by the method depicted in FIG. 5. C: The shown sequenceable reaction product can be obtained by the method depicted in FIG. 6. D: The shown sequenceable reaction product can be obtained by the method depicted in FIG. 7. E: The shown sequenceable reaction product can be obtained by the method depicted in FIG. 8a. F: The shown sequenceable reaction product can be obtained by the method depicted in FIG. 9. G: The shown sequenceable reaction product can be obtained by the method depicted in FIG. 8b.

    [0635] FIG. 4 illustrates that the present method allows to provide a pooled library of sequenceable reaction products that were obtained for different cell-laden matrices (position 1 and 2, wherein position/cell-laden matrix 1 is indicated by the barcode sequence B.sub.P1 and the position/cell-laden matrix 2 is indicated by the barcode sequence B.sub.P2), different biomolecules of interest (antigen X and antigen Y, wherein the specificity for antigen X is indicated by the barcode sequence B.sub.S1 and the specificity for antigen Y is indicated by the barcode sequence B.sub.S2) at two different time points (time-point 1 and time-point 2, wherein time-point 1 is indicated by the barcode sequence B.sub.T, and time-point 2 is indicated by the barcode sequence B.sub.T2). This concept can be extended for numerous additional positions, biomolecules of interest and time-points. In the illustrated embodiment, each sequenceable reaction product that originates from the barcode label of a single detection molecule comprises a unique UMI sequence (see UMI 1-8), thereby allowing to quantify the obtained information. The use of UMI sequences is known e.g. in the field or sequencing and therefore, does not need to be described in detail herein. As the information of sequenceable reaction products can be due to the comprised barcode sequences clearly assigned to the different positions, time points and biomolecules of interest, it is possible to pool all sequenceable reaction products into one library. The library can then be sequenced using current sequencing techniques such as NGS (Next-Generation-Sequencing), so that the information can be assessed by analyzing the sequencing results. The advantages compared to e.g. fluorescence based methods were described in detail above.

    [0636] FIG. 5 illustrates an embodiment of the present invention, wherein the barcode label that is attached to the detection molecule (in the illustrated embodiment an antibody) comprises [0637] a barcode sequence (B.sub.S) for indicating the specificity of the detection molecule, [0638] a barcode sequence (B.sub.T) for indicating a time information, and [0639] a unique molecular identifier (UMI) sequence.

    [0640] The illustrated order of these sequence elements is not limiting and may accordingly differ (e.g. B.sub.T, B.sub.S, UMI or UMI, B.sub.S, B.sub.T etc.). The barcode label may be attached via a linker such as a photocleavable spacer. The sequence elements B.sub.S, B.sub.T and UMI are in the illustrated embodiment flanked by primer sequences (1) and (2) which provide target sequences for the amplification primers. The barcode label may be attached to the detection molecule prior to contacting the detection molecule with the capture matrix (“off-chip”). The detection molecule binds the captured biomolecule of interest to which it specifically binds as has been explained in conjunction with FIG. 2. The detection molecule may be added while the capture matrix is still in contact with the cell-laden matrix, or the capture matrix with the captured biomolecule(s) of interest can be separated from the cell-laden matrix prior to contacting the capture matrix with the detection molecules. The embodiment illustrated in FIG. 5 allows to reduce the number of processing steps. Thus, after incubating the capture matrix and the cell-laden matrix (or matrices) for release (e.g. secretion) and capturing of the biomolecules of interest and subsequent washing, the capture matrix may be contacted, e.g. perfused (e.g. if a microfabricated device as disclosed herein is used), with a solution containing the one or more types of detection molecules that are associated with a barcode label which already comprises as shown in the illustrated embodiment the specificity, the quantity and the time information. The capture matrix with the bound detection molecules may then be transferred to a collection position (e.g. a collection well of a 96-well device), for performing an amplification reaction. A primer or primer combination is added, as well as reagents required for performing the amplification reaction (e.g. polymerase, dNTPs, buffers). A barcode sequence (B.sub.P) for indicating position information is introduced into the seqenceable amplification product via the primer or primer combination. In the illustrated embodiment, a primer combination in form of a primer pair is used, wherein the reverse primer hybridizes to the barcode label that is attached to the detection molecule, in the illustrated embodiment at primer sequence (2) of the barcode label. The forward primer is capable of hybridizing to the reverse strand of the barcode label that is generated when extending the reverse primer. In the illustrated embodiment the barcode sequence B.sub.P is comprised in the forward primer. Alternatively, it could be comprised in the reverse primer. Furthermore, the forward and reverse primer preferably comprise adapter sequences AS at their 5′ ends as is illustrated in FIG. 5, which introduce into the sequenceable product adapter sequences for sequencing primers that are commonly used in sequencing platforms (S and P7 are shown as illustrative, non-limiting embodiments). FIG. 5 illustrates an embodiment wherein a primer pair is used. Alternatively, a single reverse primer could be used in a linear amplification reaction (e.g. by performing 2 to 20 or 5 to 15 extension cycles with the primer), thereby producing several copies of the reverse strand of the barcode label. In such embodiment, a reverse primer may be used which comprises the barcode sequence B.sub.P and preferably, an adapter sequence AS at the 5′ end (e.g. S as shown in FIG. 5). To introduce a corresponding adapter sequence AS at the other end of the reverse strand, it is within the scope of the present disclosure to incorporate a matching adapter sequence AS in the 5′ region of the barcode label (i.e. 5′ of the sequence elements B.sub.S, UMI and B.sub.P), so that this information is incorporated into the reverse strand of the barcode label when the reverse primer is extended. In such embodiment, a primer sequence (1) is not required. Both embodiments (the use of a single primer and the use of a primer combination) allow providing a sequenceable reaction product as it is illustrated in FIG. 5C. As is apparent from the above description, the at least one oligonucleotide, optionally a primer, that is capable of hybridizing to the barcode label of the at least one type of detection molecule to which claim 1 refers corresponds in this embodiment to the primer that is used either alone or in the primer combination.

    [0641] FIG. 6: shows a variation of the embodiment illustrated in FIG. 5. The barcode label attached to the detection molecule comprises in the illustrated embodiment [0642] a barcode sequence (B.sub.S), and [0643] a unique molecular identifier (UMI) sequence.

    [0644] Furthermore, it comprises primer sequences (1) and (2). The barcode label may again be attached to the detection molecule prior to contacting the capture matrix with the detection molecule. As explained above, the detection molecules bind the biomolecules of interest captured in the capture matrix. The capture matrix comprising the captured biomolecules of interest and the bound detection molecules comprising the barcode label indicating information about the specificity of the detection molecules (barcode B.sub.S), as well as indicating a quantity information (here in form of an UMI sequence) may be in one embodiment transferred to a compartment (e.g. well) of a different device, also referred to herein as collection position (e.g. collection well), for performing an amplification reaction. Subsequently, an amplification may be performed using a primer or primer combination comprising [0645] a barcode sequence B.sub.P for indicating position information, and [0646] a barcode sequence B.sub.T for indicating time information.

    [0647] A primer combination in form of a primer pair may be used for amplification, wherein the forward primer comprises the barcode sequence B.sub.P and the reverse primer comprises the barcode sequence B.sub.T, or vice versa. Accordingly, the barcode sequences for indicating a time information (B.sub.T) and a position information (B.sub.P) can be added within a collection position (e.g. well), i.e. after separating the capture matrix from the cell-laden matrix. The used primers may furthermore comprise adapter sequences AS at their 5′ ends as shown in FIG. 5. Furthermore, it is within the scope of the present invention that both barcode sequences B.sub.P and B.sub.T are comprised on a single primer (the forward or the reverse primer), and wherein the other primer merely comprises and thus introduces an additional adapter sequence into the sequenceable reaction product. Furthermore, as explained in conjunction with FIG. 5, a single primer may be used for performing several extension cycles, wherein said primer comprises the barcode sequences B.sub.T and B.sub.P and preferably, an adapter sequence AS (e.g. S as shown in FIG. 6). A corresponding adapter sequence at the opposite end of the sequenceable reaction product may be provided by incorporating a corresponding adapter sequence on the barcode label, positioned 5′ to the barcode sequence B.sub.S and the UMI sequence. As explained above, primer sequence (1) is in such embodiment obsolete. All these embodiments allow providing a sequenceable reaction product as shown in FIG. 6C. As is apparent from the above description, the at least one oligonucleotide, optionally a primer, that is capable of hybridizing to the barcode label of the at least one type of detection molecule to which claim 1 refers corresponds in this embodiment to the primer that is used either alone or in the primer combination.

    [0648] Incorporating the quantity information (UMI sequence) as part of the barcoded label that is associated with a detection molecule (as is illustrated in FIGS. 5 and 6) is advantageous because it renders obsolete an intermediate barcode label extension step wherein an adaptor barcode oligonucleotide capable of hybridizing to the barcode label is used as template in order to introduce an UMI sequence (as is illustrated e.g. in FIGS. 8 and 9). This is advantageous if it is desired to safe handling steps.

    [0649] FIG. 7 to 9 illustrate various embodiments, wherein step d) comprises at least the following sub-steps

    [0650] (aa) hybridizing at least one oligonucleotide to the barcode label of at least one type of detection molecule and extending said barcode label using the hybridized oligonucleotide as template thereby obtaining an extended barcode label attached to the detection molecule that additionally comprises sequence information of the hybridized oligonucleotide that was used as template, and

    [0651] (bb) performing an amplification reaction with a primer or primer combination using the extended barcode label and/or the reverse complement thereof as template.

    [0652] The at least one oligonucleotide that is capable of hybridizing to the barcode label of the at least one type of detection molecule to which claim 1 refers may correspond in these embodiments to the oligonucleotide (also referred to as adaptor barcode oligonucleotide) that is capable of hybridizing to the barcode label.

    [0653] FIG. 7: The barcode label attached to the detection molecule comprises in the illustrated embodiment [0654] a barcode sequence (B.sub.S), and [0655] a unique molecular identifier (UMI) sequence, [0656] an adaptor sequence (1) at the 3′ end, and [0657] preferably a primer sequence (1) in the 5′ region of the barcode label.

    [0658] As explained above, the order of the barcode sequence B'S and the UMI sequence may vary. However, the adaptor sequence (1) is provided 3′ to these sequence elements. The barcode label, which preferably is provided by an oligonucleotide sequence that can be attached to the detection molecule via a photocleavable linker, can be attached to the detection molecule prior to contacting the capture matrix with the detection molecules. In the shown embodiment, step d) comprises a first substep (aa), wherein an adaptor barcode oligonucleotide is added, which is capable of hybridizing to the barcode label of the detection molecule. In the illustrated embodiment, the adaptor barcode oligonucleotide comprises an adaptor sequence (1).sub.R that is reverse complementary to an adapter sequence (1) of the barcode label of the detection molecule whereby it hybridizes to the barcode label. The adaptor barcode oligonucleotide may additionally comprise, as is illustrated in FIG. 7, a barcode sequence B.sub.T and a primer sequence (2).sub.R, wherein the primer sequence (2).sub.R is located 5′ to the barcode sequence B.sub.T. The adaptor barcode oligonucleotide comprising the time information B.sub.T can be added to the compartment (e.g. of the microfabricated cell culture device) comprising the cell-laden matrix and the capture matrix comprising the captured biomolecules of interest. However, it is also within the scope of the present disclosure to remove the capture matrix with the captured biomolecules of interest prior to adding the adaptor barcode oligonucleotide (“off-chip”). The hybridized adaptor barcode oligonucleotide is used as template to provide an extended barcode label, which comprises the sequence information of the adaptor barcode oligonucleotide. Reagents necessary for performing an extension reaction (e.g. polymerase, dNTPs, buffers) are added and conditions provided to allow extension of the barcode label. The 3′ end of the adapter barcode oligonucleotide is in one embodiment extendable by the polymerase, whereby a double-stranded molecule is formed which comprises the reverse strand of the extended barcode label. Alternatively, the 3′ end of the adaptor barcode oligonucleotide is blocked so that it cannot be extended by the polymerase.

    [0659] In this case, only a short double-stranded region is provided upon hybridization and extension of the barcode label, which comprises the adaptor barcode oligonucleotide and the corresponding extended region of the barcode label. The obtained extended barcode label comprises in the shown embodiment the following sequence elements: primer sequence (1), B.sub.S, UMI, adapter sequence (1), B.sub.T and primer sequence (2). The reverse complement of the extended barcode label, if provided upon extension, may be removed prior to the amplification step which is performed in step (bb) (see FIG. 7C), whereby a detection molecule is provided which comprises a single-stranded extended barcode label. Furthermore, an adaptor barcode oligonucleotide with a blocked 3′ end may be used which prevents that a reverse complement of the barcode label is formed at this stage. The oligonucleotide does not comprise sequences that would allow binding of the primer or primer combination that is used in amplification step (bb). Furthermore, the oligonucleotide can be easily removed from the amplification reaction, e.g. by purifying the amplification products using a size-selective purification method having a cut-off that removes the significantly shorter adaptor barcode oligonucleotides (and primers), while purifying the considerably longer amplification product (see FIG. 7D). After performing step d) (aa), an amplification reaction is performed in (bb). A primer or primer combination may be used that comprises a barcode sequence B.sub.P, which thereby is introduced in the amplification product. Furthermore, the primer or primer combination may comprise an adapter sequence (AS). In the illustrated embodiment, a primer pair is used, wherein the forward primer comprises the barcode sequence B.sub.P 5′ to the primer sequence that binds the reverse complement of the extended barcode label. This primer additionally comprises an adapter sequence (AS) (here: P7), 5′ to the barcode sequence B.sub.P which thereby is introduced at one end of the amplification product. The reverse primer of said pair comprises in the illustrated embodiment a primer sequence (2).sub.R that is capable of hybridizing to the primer sequence (2) of the extended barcode label and which comprises an adapter sequence (AS) (here: S) at the 5′ end which thereby is introduced at the other end of the amplification product. Alternatively, the barcode sequence B.sub.P may be provided in the reverse primer. If a single primer is used for amplification by performing several cycles of primer extensions, said primer then comprises the barcode label B.sub.P. E.g. the reverse primer shown in FIG. 7 could be used, wherein the barcode label B.sub.P is placed between the primer sequence (2).sub.R and the adapter sequence (AS) (here: S). To provide the obtained amplification product with a second adapter sequence (AS), such sequence may be already incorporated into the barcode label that is attached to the detection molecule and thereby, becomes incorporated into the amplification product. If only a single primer is used for amplification by performing several cycles of primer extension, it is not required to provide a primer sequence (1) in the barcode label. Instead, an adapter sequence AS for sequencing may be included instead of the primer sequence (1) as explained above. All these embodiments allow providing a sequenceable reaction product as it is illustrated in FIG. 7D. It follows from the above disclosure that the arrangement of the sequence elements B.sub.P, B.sub.S, UMI and B.sub.T may vary depending on the used embodiment. E.g., the barcode sequence B.sub.P may be located between the primer sequence (2) and the adapter sequence S, the order of the barcode sequence B.sub.S and UMI sequence may be reversed and the primer sequence (1) may be missing, if only a single primer is used for amplification.

    [0660] FIG. 8a: A variation of the embodiment shown in FIG. 7 is illustrated. In the shown advantageous embodiment, the barcode label comprises the barcode sequence B.sub.S and the UMI sequence is introduced via the adaptor oligonucleotide sequence. The adaptor barcode oligonucleotide comprising the UMI sequence can be added to the compartment (e.g. of the microfabricated cell culture device) comprising the cell-laden matrix and the capture matrix, or the capture matrix with the captured biomolecules of interest is removed prior to adding the adaptor barcode oligonucleotide (“off-chip”). The UMI library size might be in the range of the binding capacity of a capture matrix. For example, if the capture matrix is capable of binding 1×10.sup.6 molecules, the UMI library might comprise 1×10.sup.6 different UMI sequences to ensure that each captured biomolecule of interest is labelled with a specific UMI. In contrast, if the UMI library is incorporated into the label barcode and a plurality of cell-laden matrices and corresponding capture matrices are processed in different compartments (multiplexing), the UMI library must comprise enough molecules to label more than one capture matrix. Thus, addition of the UMI library via the adaptor barcode oligonucleotide allows to reduce the UMI library size to the maximum binding capacity of the processed capture matrix. The reverse complement of the extended barcode label, if provided upon extension, may be removed prior to the amplification step which is performed in step (bb) (see FIG. 8a C). The removal of the reverse complement of the extended barcode label is beneficial to prevent processing of polymerase-extended products resulting from unspecific hybridizations. Thereby, a detection molecule is provided which comprises a single-stranded extended barcode label. Alternatively, an adaptor barcode oligonucleotide may be used that comprises a blocked 3′ end that cannot be extended by a polymerase so that a removal is not required. As explained in conjunction with FIG. 7, a polymerase extension reaction is performed using the adaptor barcode oligonucleotide as template, whereby an extended barcode label is provided which comprises the information of the oligonucleotide. The adaptor barcode oligonucleotide may again be extendable at its 3′ end, or the 3′ end may be blocked to prevent extension by the polymerase. After substep aa) of step d), an amplification step is performed in (bb), wherein a primer or primer combination is used, which comprises the barcode sequence B.sub.T and the barcode sequence B.sub.P. The amplification reaction is preferably performed in a compartment that does not comprise the cell-laden matrix. Various transfer options for the detection matrix are described elsewhere herein. For the shown embodiment it is preferred, that the one or more capture matrices are removed from the proximity of the cell-laden matrix and transferred into a compartment (e.g. well) prior to adding the detection molecules for binding (see FIG. 2C). If a primer pair is used as is illustrated in FIG. 8a, the barcode sequence B.sub.T may be located on the reverse primer and barcode sequence B.sub.P may be located on the forward primer, or vice versa. Furthermore, the primers may comprise adapter sequences (AS) as shown in FIG. 8a (see “S” and “P7). Both barcode sequences B.sub.P and B.sub.T may also be provided on a single primer (forward or reverse), wherein said primer preferably comprises an adapter sequence (AS) for sequencing at the 5′ end. The second primer may then serve the purpose to support the amplification and to introduce a second adapter sequence (AS) for sequencing at the opposite end. Additionally, it is again possible to use a single reverse primer which hybridizes to the extended barcode label and which comprises the barcode sequences B.sub.T and B.sub.P, preferably in addition to an adapter sequence at its 5′ end. A second adapter sequence may be provided in the 5′ region of the barcode label that is attached to the detection molecule so that it is incorporated also in the obtained amplification product. As noted above, a primer sequence (1) in the barcode label is not required if a single primer is used to perform several primer extension cycles for amplification and the primer sequence (1) could be replaced by an adapter sequence AS. All these embodiments allow providing a sequenceable reaction product as is illustrated in FIG. 8a D. It again follows from the above disclosure that the arrangement/order of the sequence elements B.sub.P, B.sub.S, UMI and B.sub.T may vary depending on the used embodiment.

    [0661] FIG. 8b: A variation of the embodiment shown in FIG. 7 is illustrated. In the shown embodiment, the barcode label comprises the barcode sequence B.sub.S and the UMI sequence as well as the barcode sequence B.sub.P are introduced via the adaptor oligonucleotide sequence. The adaptor barcode oligonucleotide comprising the UMI sequence and the barcode sequence B.sub.P can be added to the compartment (e.g. of the microfabricated cell culture device or the collection well) comprising the cell-laden matrix and the capture matrix, or the capture matrix with the captured biomolecules of interest is removed prior to adding the adaptor barcode oligonucleotide as is illustrated in FIG. 8b (“off-chip”). The illustrated embodiment, wherein the adaptor barcode oligonucleotide comprising the barcode sequence B.sub.P and an UMI sequence is added after removal of the capture matrix (see FIG. 2C), is advantageous. This reduces the required UMI library size due to combination of UMIs with the barcode B.sub.P. The same UMIs can be used for different compartments/collection wells, which are clearly distinguishable and identifiable based on the barcode B.sub.P. The reverse complement of the extended barcode label, if provided upon extension due to elongation of the adaptor barcode oligonucleotide, may be removed prior to the amplification step which is performed in step (bb) (see FIG. 8b C). The removal of the reverse complement of the extended barcode label is beneficial to reduce the number of false hybridized elongation products. As explained in conjunction with FIG. 7, a polymerase extension reaction is performed using the adaptor barcode oligonucleotide as template, whereby an extended barcode label is provided which comprises the information of the oligonucleotide. The adaptor barcode oligonucleotide may again be extendable at its 3′ end, or the 3′ end may be blocked to prevent extension by the polymerase. After step aa), an amplification step is performed in (bb), wherein a primer or primer combination is used, which comprises the barcode sequence B.sub.T. The amplification reaction is preferably performed in a compartment that does not comprise the cell-laden matrix (transfer options are described herein). If a primer pair is used as illustrated in FIG. 8b, the barcode sequence B.sub.T may be located on the forward primer, or alternatively on the reverse primer. Furthermore, the primers may comprise adapter sequences (AS) as shown in FIG. 8b (see “S” and “P7). Additionally, it is again possible to use a single reverse primer which hybridizes to the extended barcode label and which comprises the barcode sequences B.sub.T, preferably in addition to an adapter sequence at its 5′ end. A second adapter sequence may be provided in the 5′ region of the barcode label that is attached to the detection molecule so that it is incorporated also in the obtained amplification product. As noted above, a primer sequence (1) in the barcode label is not required if a single primer is used to perform several primer extension cycles for amplification and the primer sequence (1) could be replaced by an adapter sequence AS. All these embodiments allow providing a sequenceable reaction product as it is illustrated in FIG. 8b D. It again follows from the above disclosure that the arrangement/order of the sequence elements B.sub.P, B.sub.S, UMI and B.sub.T may vary depending on the used embodiment.

    [0662] FIG. 9: A further variation of the embodiment shown in FIG. 7 is illustrated. The barcode label only comprises the barcode sequence B.sub.S while the UMI sequence and the barcode sequence B.sub.T are introduced via the adaptor oligonucleotide sequence. These two sequence elements are flanked 3′ by the adaptor sequence (1).sub.R and 5′ by the primer sequence (2).sub.R. The order of B.sub.T and UMI may be reversed in the adaptor barcode oligonucleotide. The adaptor barcode oligonucleotide comprising the UMI sequence and the barcode sequence B.sub.T can be added to the compartment (e.g. of the microfabricated cell culture device) comprising the cell-laden matrix and the capture matrix (“on-chip”, i.e. time and quantity information (UMI) may in this embodiment added within a microfabricated compartment containing the capture matrix and the cell-laden hydrogel matrix), or the capture matrix with the captured biomolecules of interest may be removed prior to adding the adaptor barcode oligonucleotide (“off-chip”). As explained in conjunction with FIG. 7, a polymerase extension reaction is performed using the adaptor barcode oligonucleotide as template, whereby an extended barcode label is provided which comprises the sequence information of the oligonucleotide. The adaptor barcode oligonucleotide may again be extendable at its 3′ end, or the 3′ end may be blocked to prevent extension by the polymerase.

    [0663] After step aa), an amplification step is performed in (bb), wherein a primer or primer combination is used, which comprises the barcode sequence B.sub.P. The amplification reaction is preferably performed in a compartment that does not comprise the cell-laden matrix. If a primer pair is used as illustrated in FIG. 9, the barcode sequence B.sub.P may be located on the forward primer, or alternatively on the reverse primer. Furthermore, the primers may comprise adapter sequences (AS) as shown in FIG. 9 (see “S” and “P7). Additionally, it is again possible to use a single reverse primer which hybridizes to the extended barcode label and which comprises the barcode sequences B.sub.P, preferably in addition to an adapter sequence at its 5′ end. A second adapter sequence may be provided in the 5′ region of the barcode label that is attached to the detection molecule so that it is incorporated also in the obtained amplification product. As noted above, a primer sequence (1) in the barcode label is not required if a single primer is used to perform several primer extension cycles for amplification and the primer sequence (1) could be replaced by an adapter sequence AS. All these embodiments allow providing a sequenceable reaction product as it is illustrated in FIG. 9D. It again follows from the above disclosure that the arrangement/order of the sequence elements B.sub.P, B.sub.S, UMI and B.sub.T may vary depending on the used embodiment.

    [0664] FIG. 10 is an illustration of a particle trap 17 for encapsulation of a single particle, here a single-cell. The trap 17 is located above a microfabricated elastomer valve portion 14. [0665] FIG. 10A: The top microfabricated layer 23 is first perfused with a particle suspension 36, i.e. here a cell suspension. Single cells 20 are trapped and immobilized in the hydrodynamic trap 17 located above a microfabricated valve portion 14. Subsequent opening of the microfabricated valve portion 14 results in a fluid flow from the top layer 23/second channel 12 into the bottom layer 21/first channel 11 that is filled with an immiscible (with the respect to the fluid within the second channel) second fluid 37, in particular an oily fluid. The trapped cell 20 is thereby transferred into the formed droplet 31, wherein the fluid of the cell suspension 36 surrounds the captured cell 20. The fluid of the cell suspension 36 and the particle constitutes a droplet 31. [0666] FIG. 10B: is an illustration of the particle trap 17 of FIG. 10A in top view. The generic single particle trap 17 is located above/adjacent to the microfabricated elastomer valve portion 14. The trap 17 comprises a bottleneck section 16, which fluid opening is smaller than the particle 20 to be trapped. A first particle (cell) arriving at the trap is captured by the trap. All further particles (cells) arriving subsequently at the trap take the way along a bypass section 18. 38 illustrates an optional impedance measuring device, 39 illustrates an optional radio frequency application device. [0667] FIG. 10C: is an illustration of an amended trap group for the immobilization of two particles 20, in particular cells, located in two separate neighboring traps 17n above the microfabricated valve portion 14. Opening of the valve portion 14 may result in a co-encapsulation of two trapped cells 20 into one droplet 31, because the valve portion 14 leads from both traps 17n into the same first channel 11 below both traps 17n. Using this embodiment, two different cells 20 can be encapsulated within one single droplet 31. [0668] FIG. 10D shows a trap group in schematic view. Each of the neighboring traps 17n is loaded from a separate channel 12′, 12″, in which the same pressure p2 is applied to the fluid, to achieve droplets of the same size. At first the traps 17n are loaded; when all traps 17n are loaded a washing fluid can be applied to clean the trapped cells. Subsequently the valve portions 14 are opened to include the cells 20 through one valve section 14 simultaneously into one droplet 31. A plurality of such trap groups having two neighboring traps 17n can be arranged in one test device.

    [0669] FIG. 11 is an illustration of hydrodynamic resistances of a microfabricated geometry for the controlled removal and transfer of particles such as capture matrices and/or cell-laden hydrogel matrices to an exit portion. In addition, that microfabricated geometry can be arranged within an array enabling the positioning and removal of hundreds to thousands of particles. Said microfabricated geometry comprises the hydrodynamic resistances R0, R1, R2, R3, R4 within one compartment 32, here at the example of compartment 32m2n2 in position of column m2 and row n2. R0 indicates the hydrodynamic resistances at a matrix trap 33, R1-R4 indicate the hydrodynamic resistances of different paths within compartment 32, with R1, R4>R2, R3. P1 indicates an entrance of a main fluid flowing through the compartment 32 to an exit indicated by P2. The main feeding channel 41 optional here. [0670] FIG. 11A: During normal operation the main fluid stream moves from top to down (first direction of flow S1 along first path of flow 51 or optional along main feeding channel 41), since the stream takes the “easier way” through smaller resistances R2, R3. Merely a negligible part of the fluid flows through path of resistances R1, R4. Here all triggering commands Cm2, Cn2 are set to zero. [0671] FIG. 11B: By triggering a valve Vm2 by command Cm2=1 in the path of R2, resistance R2 of this path will significantly increase. The main fluid now moves from P1 to P2 via paths of resistances R4 and R3 along third path of flow 53. The flow at R0 is now stopped, but not reversed. [0672] FIG. 11C: By triggering a valve Vn2 in the path of R3 command Cn2=1, resistance R3 of this path will significantly increase. The main fluid now moves from P1 to P2 via paths of resistances R2 and R1 along fourth path of flow 54. The flow at R0 is now stopped, but not reversed. [0673] FIG. 11D: Only when both the resistances in paths of R2 and R3 is increased, by triggering the valves Vm2 and Vn2 by commands Cm2 and Cn2 set to 1, the flow at position R0 within the matrix trap 33 is reversed. The main fluid now moves from P1 to P2 via paths of resistances R4, R0 and R1 along fourth path of flow 54. A matrix 31 that is located within the matrix trap 33 at R0 is subsequently removed from the trap position. The group of the both valves Vm2, Vn2 is here called at the valve arrangement 40m2n2 of the observation chamber 32m2n2 exemplary.

    [0674] The presented microfabricated geometry can be e.g. used to accomplish the disclosed methods. In particular, the microfabricated geometry can be used to position for example one-cell-laden hydrogel matrix and a capture matrix in proximity within one compartment. In addition, said microfabricated geometry enables the removal of the capture matrix while the cell-laden matrix remains within its position. One advantage of the presented microfabricated geometry is its compatibility with an array arrangement. Thus, multiple microfabricated geometries can be connected to generate an addressable n×m array containing at least one cell-laden matrix and a capture matrix at each position (n|m) of said array and while still being capable of transferring capture and/or cell-laden matrices located at a defined position. Matrices such as capture matrices or cell-laden matrices can be delivered to the microfabricated geometry within a droplet that is located within a fluid that is immiscible with an aqueous fluid. Said fluid can be an oil such as fluorinated oil (e.g. HFE-7500). If matrices are provided within a droplet, the matrix formation may not have been started, may be ongoing or may be finished (droplet contains a fully polymerized/gelled matrix). In addition, fully polymerized/gelled matrices located within an aqueous phase may be delivered to the microfabricated geometry. For example, capture matrices may be formed prior to the addition to the cell culture device enabling a detailed quality control of the capture matrices using various characterization methods.

    [0675] FIG. 12 shows simulations with a generic microfabricated cell culture device for trapping matrices, in particular spherical hydrogel matrices (e.g. cell-laden matrix, capture matrix), in a specific location 32, which is also described in more with reference to the circuit diagram of FIG. 11. [0676] FIGS. 11A and 12A: Normal operation. No microfabricated valves are closed; consequently resistances R2 and R3 in fluid lines 502 and 503 are much smaller than resistances R1 and R4 in fluid lines 501 and 504. The fluid flow perfuses the trap geometry 33 from top to bottom in direction S1. Thus, a particle (cell) is immobilized within the trapping structure 33. [0677] FIGS. 11B and 12B: The bottom left microfabricated valve represented by resistance R3 is closed. The main fluid stream goes through the upper channel. [0678] FIGS. 11C and 12C: The main fluid stream goes through the bottom channel. A particle is pushed into the trap. [0679] FIGS. 11D and 12D: Only when both microfabricated valves represented by resistances R2 and R3 are closed the reverse fluid flow in direction S2 removes that particle from the trapping structure 33.

    [0680] In terms of the current disclosure, the generic trapping structure 33 is adapted to position at least two particles such as a cell-laden matrix and a capture matrix. A detailed description of such a positioner is given in FIG. 13 to 17. The generic microfabricated cell culture can be operated in several states including the perfusion with fluid direction S1 and the perfusion in fluid direction S2. The perfusion in fluid direction S1 enables the efficient washing of capture matrices after analyte binding and subsequent washing with detection molecules. In addition, the generic microfabricated compartments can be closed thereby enabling the generation of a closed reaction compartment having a defined reaction volume. This is critical, as secreted analytes have to remain within the same reaction compartment as the capture matrix to allow the binding of analytes to the capture molecules. The perfusion in fluid direction S1 enables the removal a capture matrices, for example after the detection molecules were added and subsequent transfer into another device. The controlled transfer of capture matrices to a pre-defined position of another device is a crucial step as the capture matrix can be further processed without loosing the information, that the capture matrix was positioned close to the cell-laden matrix at position (n1m). This information is required for performing a unique assignment of the data generated by analysing the capture matrix (secretion profiled) to the corresponding cell(s) that have secreted the analysed molecules.

    [0681] FIG. 13 to 15 illustrates embodiments for removing a matrix, e.g. a capture matrix, by reverse flow cherry picking (RFCP):

    [0682] FIG. 13A shows two matrices located within close proximity, e.g. a capture matrix (31C) and a cell-laden matrix (31A). A reverse flow results in a force F2 acting on capture matrix 2 (31C) and in a force F1 acting on cell-laden matrix 1 (31A) with F2 being larger than F1. Thus, at a certain flow rate only capture matrix 2 (31C) is removed, while the cell-laden matrix 1 (31A) remains in the compartment. FIG. 13B shows corresponding hydrodynamic resistances for generating two different forces acting on said matrices.

    [0683] FIG. 14 shows the removal of particles in particular matrices (31C, 31A) located within a positioning mean provided in frame of a RFCP mechanism by using different reverse flow rates. An increase of the reverse flow rate might result in a removal of a first capture matrix 31C while all matrices located within different (microfabricated) compartments might remain within their position. A further increase of the flow rate might result in a removal of a second matrix from the same compartment (e.g. the cell-laden matrix 31A) without removing matrices located within other compartments. This is advantageous, as capture matrices can be first transferred for subsequent processing and analysis. Afterwards, the cell-laden matrix may be collected as well for further characterization of said cell(s) using established methods. In particular, the collected cell(s) may be characterized in terms of their genotype (e.g. by using RT-PCR or (single cell) RNA-seq) enabling the assignment of genotypic information to phenotypic information (such as the generated secretion profile of the one or more biomolecules of interest as presented in the current disclosure).

    [0684] FIG. 15 shows the sequential removal of three particles in particular matrices or droplets (droplets 31-A-C) by RFCP which have been positioned in proximity by using a positioner. In one embodiment, matrix 31A may be a cell-laden matrix containing cell(s) of type 1, matrix 31B may be a cell-laden matrix containing cell(s) of type 2, whereas cell(s) of type 1 and type 2 may be the same or different, and matrix 31C may be a capture matrix. A reverse flow results in a force F3 acting on a matrix 31C, in a force F2 acting on matrix (matrix 31C) and in a force F1 acting on matrix 31A with F3 being larger than F2 being larger than F1. Thus, at a certain flow rate only matrix (matrix 31C) is removed. Increasing the reverse flow rate leads to the sequential removal of the other matrices. B) Corresponding hydrodynamic resistances for generating three different forces acting on said matrices. An exemplary embodiment is also shown in FIG. 16. The removal of the capture matrix (31C) without removing the matrices 31A and 31B enables the repeated positioning of a “fresh” capture matrix having no analytes bound to the capture molecules thereby allowing the detection of analytes secreted within different time intervals. In one embodiment, the matrices 31A and 31B as well as the capture matrix 31C are located within a droplet that is located within a fluid immiscible with an aqueous fluid. Within the positioner the droplets containing the matrices 31A-C interface with each other. In particular, the droplets containing the matrices 31A-C merge with each other forming one droplet containing the matrices 31A-C thereby reducing the reaction volume to the volume of approximately the three matrices 31A-C which increases the analyte concentration and thus the sensitivity. This may also be done with two droplets/matrices, one cell-laden matrix and one capture matrix. In addition, the matrix 31C may be removed from the common droplet and a droplet fission may be performed using the RFCP mechanism. A fresh droplet containing a capture matrix may be delivered to the remaining droplet containing matrix 31A and 31B. In another advantageous embodiment, the matrices 31A and 31B may be incubated within one common droplet first. Afterwards, a capture matrix located within a droplet may be positioned and merged with the common droplet containing matrices 31A and 31B. This has the advantage, that secreted molecules can first accumulate within the common droplet thereby enabling paracrine and autocrine signalling and subsequently be captured by addition of the capture matrix. The same procedure may be performed using a positioner for positioning of only two particles instead of three.

    [0685] FIG. 16: FIG. 16B shows a generic location, details of which are shown in FIG. 16A. The location comprises two bypass sections 35 circumventing a group of positioner 33. Here three bottleneck sections 34A, 34B, 34C are provided in sequence each defining a positioner 33A, 33B, 33C. During loading of the location a first particle in particular a droplet/matrix arriving at the positioners 33 will move up to the first positioner 33A and will be retained in the first positioner 33A. A second droplet/matrix arriving subsequently will move up to the second positioner 33B upstream of the first positioner 33A and will be retained in the second positioner 33B. A third droplet/matrix arriving subsequently will move up to a third positioner 33C upstream of the second positioner 33B and will be retained in the third positioner 33C. It is possible to provide any number of bottleneck sections 34/positioners 33 to enable a row of droplets/matrices 31 of a predetermined number. When all the positioners are occupied further droplets/matrices will follow the bypass section 35 and approach the locations at a downstream position along first fluid direction S1. When the fluid is reversed to untrap the droplets/matrices at first droplet/matrix upstream (when viewed in first fluid direction S1) in third bottleneck section 34C will be untrapped. Due to the hydraulic design in the droplet/matrix trap the droplets/matrices retained in the upstream positioner 33C will be subject of an increased hydraulic pressure compared to the droplets/matrices retained in the downstream positioner 33A, 33B. Thus, upon reversal of the fluid direction into the second fluid direction S2 at first the droplet/matrix in the most upstream positioner 33C will be untrapped and can be delivered to an exit section e.g. at P2 (see FIG. 21). At second the fluid pressure between P1 and P2 will be increased, so that subsequently also the droplets/matrices retained in the more downstream positioner 33A, 33B will be untrapped and will also be delivered to exit at P2. A suitable hydraulic design can be obtained by CFD simulations.

    [0686] FIG. 17 shows a sequential removal of three matrices in a trap having 3 bottleneck sections each by a first (downstream) matrix 31A, second matrix 31B and third (upstream) matrix 31C, without affecting matrices located within other compartments (for example from a cell culture device, preferably a microfabricated cell culture device). [0687] During a first untrapping period I low pressure or flow rate p1 is applied through fluid, so that all matrices remain trapped. [0688] During a second period an increased pressure or flow rate p2 is applied through the fluid, which is strong enough to remove merely upstream matrix 31C; the other matrices 31B, 31A remain trapped. [0689] During a third period Ill a further increased pressure or flow rate p3 is applied through the fluid, which is strong enough to remove second matrix 311B; the downstream matrix 31A remains trapped. [0690] During a fourth period IV a further increased pressure or flow rate p4 is applied through the fluid, which is strong enough to remove third upstream matrix 31A. The pressure can be applied through input P1 (see FIG. 6).

    [0691] FIGS. 13 and 14 show the same concept as described with reference to FIGS. 15 and 16, but merely for the use of two matrices 31A, 31C to be retained within one matrix trap, having two bottleneck sections 34A, 34C.

    [0692] FIG. 18 is an illustration of a workflow for generating a time-lapse profile of one or more biomolecules of interest. To this end, at least two matrices (a cell-laden matrix 31A, and a capture matrix 31B) are positioned in a first step within a trap (33A, 33B) located within a compartment (32). This may be a trap for selective removal of trapped matrices as an exemplary embodiment is also shown in FIGS. 13 and 14. The cell-laden matrix (31A) contains at least one cell (20). In addition, said cell-laden matrix (31A) may be held stationary for a defined period. A capture matrix (31B) is positioned next to the cell-laden matrix (31A). The capture matrix may contain one or more types of capture molecules for capturing one or more biomolecules of interest that are secreted by the cell (20) provided in the cell-laden matrix. In a particular embodiment, the fluid surrounding the trapped matrices might be replaced by an oily fluid in a next step. Thus, the reaction volume is decreased to approximately the volume of both matrices (31A,31B). This has the advantage, that the reaction volume is fixed to a defined volume and the concentration of secreted biomolecules of interest is increased thereby increasing the measurement sensitivity of a potential detection mechanism. In a next step, both matrices (31A, 31B) may be held stationary for a defined period in which secreted biomolecules of interest might be released from the cell and diffuse to the capture matrix 31B where they are bound by the provided capture molecules. Afterwards, the fluid surrounding said matrices might be exchanged again enabling washing of trapped matrices and adding a detection molecule that is labelled with a barcode label as is described herein. The capture matrix (31B) is then removed by applying a reverse flow as disclosed and may be collected in a compartment of another device, e.g. the well (“collection position”) of another format, such a well plate while the cell-laden matrix 31A is held stationary. Afterwards, a new second (capture) matrix (31B) is provided and positioned again in 33B and the process is repeated. This method has the advantage, that secreted biomolecules of interest can be captured in a time-lapse manner and analysed either within the compartment (32) or after collection of said matrices (31B) in a different device. Secreted molecules may be cytokines, growth factors and the like.

    [0693] FIG. 19 is an illustration of data that might be generated using the described time-lapse cytokine profiling technique. The method according to the present invention which uses different barcode sequences B.sub.S, B.sub.T and/or B.sub.P that are provided within a sequenceable reaction product, that moreover can be pooled as is described herein has the advantage that the data can be generated in a time and cost efficient manner using sequences approaches. In addition, said data may be coupled to additional information about cell(s) located within the cell-laden matrices (e.g. phenotypic data gained with methods such as immunostaining, genotypic data gained with methods such as RT-PCR, RNA-seq).

    [0694] It is furthermore referred to following Figures of PCT/EP2018/074526, which are including the corresponding figure description herein incorporated by reference: [0695] FIG. 2, showing a microfluidic array. Said array may be used for cultivating and analyzing hundreds to thousands of cell-laden matrices with the disclosed methods and for handling (positioning and transfer/removal) of the corresponding capture matrices. [0696] FIGS. 22, A, B and C showing an array of the compartments controlled by RFCP. [0697] FIG. 31 shows a workflow for the on-demand multi step stimulation of cells in a matrix. [0698] FIG. 35 shows schematically an embodiment of a microfabricated geometry for immobilizing a matrix. Said microfabricated geometry can be adjusted for the immobilization

    [0699] FIG. 20 is an illustration of the structure of a microfabricated cell culture device that enables the processing of capture matrices (e.g. contacting with detection molecules) located within another compartment than the compartment containing cell-laden matrices. This has the advantage, that the capture matrix processing can be separated from the cultivation of cells. Thereby, cell(s) located within cell-laden hydrogel matrices are not affected by the processing of the capture matrix. In addition, analytes secreted during the processing of a capture matrix comprising bound analytes from a prior incubation period, can be captured again using a “fresh” capture matrix that initially (during delivery) has no analytes bound thereby reducing the loss of any molecules secreted during the processing of the capture matrix. To enable the separation of the capture matrix processing from the cultivation process, a further compartment for the processing of the capture matrix (processing chamber) is added to the device. The compartment containing the one or more cell-laden matrices (microfluidic cell culture compartment) is connected to a processing chamber for receiving at least one capture matrix. Both compartments (the processing chamber for the at least one capture matrix as well as the corresponding microfluidic cell culture chamber for the at least one cell-laden matrix) may be structured as illustrated in FIGS. 11-17. The separation of the two processes may be done by connection the exit portion p2 of a microfluidic cell culture chamber with the feeding line 41 of a processing chamber. In addition, the exit portion of a microfluidic cell culture chamber may be connected to the exit portion (common exit portion) of at least one second microfluidic chamber. At least one valve may be used to switch between the feeding line of a processing chamber and the common exit portion. Thus, a matrix that is removed from the microfluidic cell culture chamber may be either directed towards a processing chamber or to the common exit portion. For example, a capture matrix located within microfluidic cell culture chamber 1,2 may be directed to the feeding line of processing chamber 1,1 and the capture matrix may be positioned within said processing chamber. A cell-laden matrix may be directed towards the common exit portion for direct collection without any processing. The exit portion p2 of a processing chamber is connected to the exit portion of at least one second processing chamber. Thus, after the processing of a capture matrix is done, the capture matrix can be removed from the processing chamber and be transferred into another format of a device. In addition, the processing chambers are connected in series and can be perfused without perfusing the microfluidic cell culture chambers. This can be done as all processing chambers share a common feeding line. In addition, all microfluidic cell culture chambers share a common feeding line that is different than the feeding line for the processing chambers. The processing chambers and the microfluidic cell culture chambers may be arranged in an addressable n×m array in which the flow at a position n|m can be reversed by providing a common group command as shown in FIG. 11.

    [0700] FIG. 21 illustrates an embodiment, wherein the cell-laden matrix is incubated in a compartment of a cell culture plate. The cell-laden matrix (42) comprising at least one cell (43; here multiple cells) is provided in a compartment (44), e.g. a well, of a cell culture plate. FIG. 21 only shows the compartment (well) of such cell culture plate. The cell-laden matrix (42) is covered by a liquid (45), e.g. cell culture media. After incubating the cell-laden matrix (42), at least one capture matrix (46) is added to the compartment (44) which contains the liquid (45) and the cell-laden matrix (42). The capture matrix is provided in the illustrated embodiment by a plurality of capture beads. The added capture matrix (46) comprises one or more types of capture molecules which allow binding of the one or more biomolecules of interest (47) as disclosed herein. After binding of the released biomolecule(s) of interest to the capture matrix (in the shown embodiment a plurality of capture beads), the capture matrix with the bound biomolecules of interest (47) can be transferred, e.g. to another position, such as a different compartment (e.g. different well of a cell culture plate). Then, one or more further cycles of incubation of the cell-laden matrix (43) and capture matrix (46) addition can be performed (see arrow). Afterwards, steps c) and d) and optionally step e) of the method according to the present disclosure are performed (not shown in Figure).

    EXAMPLES

    [0701] In the following examples, materials and methods of the present invention are provided. It should be understood that these examples are for illustrative purposes only and are not to be construed as limiting this invention in any manner.

    I. General Method Steps

    [0702] Cell Encapsulation and Matrix Positioning

    [0703] A single cell or multiple cells are encapsulated within a matrix to provide a cell-laden matrix. The matrix material is preferably provided by a hydrogel. Encapsulation into the matrix might be done using techniques such as droplet formation using flow focusing geometries or droplet on demand systems with corresponding sorting mechanisms, subsequent hydrogel formation and demulsification of cell-laden hydrogel matrices located within droplets. A suitable encapsulation method for a particle, here at least one cell, is described in detail in PCT/EP2018/074526, herein incorporated by reference. The described methods inter alia allow to center the cell within a hydrogel bead, thereby providing a cell-laden matrix. Droplet and hydrogel matrix size may be selected in embodiments from a range of 1 μm to 1000 μm, preferably 5 μm to 500 μm, more preferably 30 μm to 200 μm. Suitable ranges were also described elsewhere herein.

    [0704] The provided cell-laden matrix is then positioned within a compartment of the cell culture device. The compartment of the cell culture device comprising the cell-laden matrix may have one or more of the following characteristics: [0705] i. it can be selectively opened and closed using microfabricated valves, such as Quake Valves or vertical membrane valves as described in PCT/US2000/017740 or preferably PCT/EP2018/074526, respectively; [0706] ii. it comprises a positioning mean which can be a microfabricated geometry for positioning or immobilizing matrices (e.g. cell-laden matrix and/or capture matrix); and/or [0707] iii. it comprises a microfabricated geometry for removing one or more matrices while one or more other matrices remain within their position. This might be achieved by a valve arrangement adapted to provide fluid passing through a positioning mean (e.g. RFCP geometry as discussed above and as disclosed in PCT/EP2018/074526).

    [0708] A capture matrix comprising capture molecules (e.g. immobilized antibodies) having a specificity against a defined biomolecule of interest (e.g. target analytes such as cytokines, chemokines, TNF or interleukins) is provided and positioned next to or in close proximity to the cell-laden matrix (e.g. preferably within the same compartment of a cell culture device, preferably a microfabricated compartment of a cell culture device) so that biomolecules of interest that are released, e.g. secreted, from the at least one cell may diffuse towards the capture matrix so that the capture molecules of the capture matrix can bind and thus capture the biomolecules of interest. Each microfabricated compartment contains a pre-defined number of matrices. In a particular embodiment, a microfabricated compartment comprises exactly one cell-laden matrix and one capture matrix. The distance between the capture matrix and the cell-laden matrix might be between 0 μm (the hydrogel matrices are in direct contact) to 100 μm or more. The positioning of a pre-defined number of different matrices might be achieved using a position mean such as a hydrodynamic trapping structure, preferably a microfabricated geometry for matrix immobilization (as disclosed herein and in PCT/EP2018/074526, herein incorporated by reference).

    [0709] Generation of Compartments

    [0710] An isolated compartment with a defined volume may be created by selectively closing/isolating the compartment e.g. by actuating corresponding microfabricated valves and/or exchanging the first fluid (e.g. aqueous phase) against a second fluid (which may be a phase immiscible with water, such as an oil phase, preferably a fluorinated oil; also referred to as biphasic compartment generation as described in PCT/EP2018/074526 and PCT/EP2018/074527), whereby the reaction volume is reduced. At this step the capture matrix and the cell-laden matrix are located within the same hydrophilic reaction volume. The reaction volume may be closed by valve actuation, whereby an isolated compartment is generated. In a particular embodiment, the isolated and closed microfabricated compartment has a volume in the range of 1 nL to 500 nL, preferably 10 nL to 50 nL.

    [0711] In another advantageous embodiment, the reaction volume can be further reduced by using an alternating biphasic compartment generation described in the present disclosure. Thus, in one embodiment the aqueous phase surrounding the positioned hydrogel matrices might be exchanged by an immiscible fluid such as a fluorinated oil (e.g. HFE-7500) thereby reducing the volume compartment to a volume that approximately corresponds to the volume of the trapped matrices. In one embodiment, the reduced volume of the aqueous phase containing the hydrogel matrices might be in the range of 0.05 nL to 10 nL, preferably 0.4 nL to 0.6 nL.

    [0712] Incubation of the Cell-Laden Matrix

    [0713] The cell-laden matrix is incubated for a defined time period (e.g. 1 h, 2 h or more). The cell-laden matrix within the compartment is provided in a surrounding/under conditions so that cell(s) located within the matrix may release, e.g. secrete, one or more biomolecules of interest. The biomolecules of interest diffuse to the neighboring capture matrix where they are bound by the immobilized capture molecules having the corresponding specificity towards the released biomolecule of interest. In case an alternating biphasic compartment was generated, the biomolecules of interest may remain within the aqueous phase comprised in the cell-laden matrix, wherein the provided a capture matrix also comprises an aqueous phase, which can become available for diffusion of biomolecules of interest.

    [0714] Intermediate Steps Such as Washing Steps

    [0715] Washing steps may be performed at any time point throughout the method according to the present disclosure.

    [0716] The fixed matrices may optionally be washed with a washing buffer such as PBS to remove unbound biomolecules of interest by perfusing the compartment of the cell culture device.

    [0717] According to one embodiment, the isolated compartment is again opened (e.g. by actuating a microfabricated valve). If an aqueous phase surrounding the matrices has been replaced by an oil phase (e.g. HFE-7500), the oil phase may again be replaced by an aqueous phase. This is done by perfusing the microfabricated system with an aqueous phase such as PBS. This procedure is very efficient, as the same buffer can be perfused through all compartments.

    [0718] Adding One or More Types of Detection Molecules

    [0719] The capture matrix is then contacted with one or more types of detection molecules. The compartment comprising the capture matrix may be in one embodiment perfused with a solution containing one or more types of detection molecules (e.g. with an adjustable concentration) for a defined time period. The detection molecules bind to their captured biomolecules of interest. The detection molecules are associated with a barcode label which comprises at least a barcode sequence (B.sub.s) indicating the biomolecule of interest specificity of the detection molecule. Conjugated detection molecules comprising a barcode sequence for their specificity are commercially available (e.g. from Biogen) and may be used in conjunction with the present invention.

    [0720] After adding and incubating the one or more types of detection molecules with the capture matrix, a washing step may be performed (e.g. with PBS) to remove unbound detection molecules.

    [0721] The capture matrix with the bound biomolecules of interest may also be transferred to a separate device prior to adding the detection molecules.

    [0722] One or more sequence elements may be added to the barcode label, such as a barcode sequence B.sub.T, an UMI sequence for quantification, and/or a barcode sequence B.sub.P, and/or an adapter sequence (AS) for a sequencing platform. As disclosed herein, numerous embodiments exist to introduce these sequence elements and to thereby generate a sequenceable reaction product that comprises one or more of these additional sequence elements.

    [0723] Optionally, Adding an Oligonucleotide

    [0724] As was described e.g. in detail in conjunction with the above Figures, after addition of the one or more types of detection molecules and optionally washing the capture matrix, an oligonucleotide may be added to extend the barcode label. Suitable embodiments for the oligonucleotide are described in detail elsewhere herein. Such oligonucleotide may comprise e.g. a barcode sequence B.sub.T, an UMI sequence and/or a barcode sequence B.sub.P.

    [0725] In one embodiment, the oligonucleotide is capable of hybridizing to the barcode label (also referred to herein as adaptor barcode oligonucleotide). To allow primer extension, the required reagents (e.g. polymerase, dNTPs etc.) may be added after the oligonucleotide was hybridized or the reagents may added, e.g. perfused, into the compartment, together with the oligonucleotide in case a microfabricated device as described herein is used. Conditions are provided to allow extension of the barcode label using the oligonucleotide as template, whereby an extended barcode label is obtained. The polymerase extension reaction can be conducted within in the compartment. Alternatively, the capture matrix can be transported to another position (compartment) of the cell culture device, or a different device, before performing the polymerase extension reaction.

    [0726] In an alternative, however less preferred embodiment, the oligonucleotide may be ligated to the barcode label to provide an extended barcode label. Suitable reaction conditions are provided (e.g. ligase, ligase buffer) to allow ligation.

    [0727] Transfer and Collection of the Capture Matrix

    [0728] The capture matrix (present at a particular position of the cell culture device, e.g. a particular position of an array of positions; and transferred at a pre-defined time point t) comprising the binding complexes of the one or more types of capture molecules, one or more bound biomolecules of interest, and the bound detection molecules may be removed and transferred to a different compartment (position (m, n) being the position of the (preferably microfabricated) compartment, in which the capture matrix (and the corresponding cell-laden matrix) has/have been incubated, t, being the time point at which the capture matrix was removed from the (microfabricated) compartment and transferred e.g. into another format). Therefore, a reverse flow cherry picking mechanism may be used as described in the disclosure of PCT/EP2018/074526, which is herein incorporated by reference, to transfer the capture matrix to a pre-defined collection position (wherein the position information (e.g. compartment position (m, n)) may be maintained by the particular collection position, wherein the collection position for different compartment positions (m, n) may be different) at a pre-defined time point t.sub.x The collection position may e.g. be the well of another format such as a 1536 well plate. The cell-laden matrix can remain in its original position (e.g. inside the microfabricated compartment). According to a particular example, the cell-laden matrix may be trapped in its original position by a microfabricated geometry for matrix immobilization. Also the capture matrix may be trapped by such said microfabricated geometry. The removal of the capture matrix may advantageously be achieved by selectively changing the direction and amount of a fluid by a valve arrangement (also referred to as RFCP mechanism). Such a valve arrangement is described above and the disclosure also applies here. Furthermore such a valve arrangement is disclosed in PCT/EP2018/074526, which is herein incorporated by reference. Such a procedure can be advantageously performed according to the present disclosure, in particular in conjunction with the preferred microfabricated cell culture device.

    [0729] After removal of the capture matrix from the proximity of the cell-laden matrix (e.g. removal of the capture matrix from the microfabricated geometry for matrix immobilization), another capture matrix may be added (e.g. to the free position of the microfabricated geometry for matrix immobilization next to the cell-laden matrix). This can be advantageously achieved by the valve arrangement disclosed above (also referred to as the RFCP mechanism). The capture matrix may be added directly or after a predetermined time interval. Hence, the steps described above, starting with the matrix positioning in proximity to the cell-laden matrix may be repeated one or more times. Thereby, information about the released biomolecules of interest at the different time-points is collected and provided in form of a sequenceable reaction product. The method allows to generate a time-resolved profile of released biomolecules of interest.

    [0730] Amplification Reaction

    [0731] After collecting the desired number of capture matrices from one or more time points or one time-point and numerous positions, an amplification reaction is preferably performed to generate multiple copies of the optionally extended barcode label. As is described herein, one or more sequence elements may be added with the primer or the primer combination that is used for amplification, such as a barcode sequence B.sub.P, a barcode sequence B.sub.T, and/or an adapter sequence (AS) for a sequencing platform. If an UMI sequence is used for quantification, it is introduced prior to amplification. According to one embodiment, a forward primer (e.g. oligonucleotide P-fwd) and a reverse primer (e.g. oligonucleotide T-rev) is used. As is disclosed herein, one or both of the primers of such primer pair may comprise one or more of the sequence elements B.sub.P, B.sub.T, and/or AS.

    [0732] The amplification may be a polymerase extension reaction with a single primer (performing repeated cycles of primer extension) or a PCR reaction using a primer pair.

    [0733] The amplification reaction using one or more (optionally extended) barcode labels as template is preferably performed within a collection well of a device, such as a well-plate. A LightCycler® 1536 Multiwell Plate and a LightCycler® 1536 Instrument from LifeScience may be e.g. used. As is disclosed herein, an amplification reaction may be e.g. performed in a single collection well using as template the (optionally extended) barcode labels from [0734] a capture matrix obtained at a single time point from at least one cell-laden matrix located in a single compartment; [0735] a plurality of capture matrices obtained at two or more time points from at least one cell-laden matrix located in a single compartment, wherein preferably the barcode B.sub.T is introduced into the (optionally extended) barcode label prior to performing the amplification reaction; [0736] a plurality of capture matrices obtained from a plurality of cell-laden matrices located in a plurality of different compartments at one or more time points, wherein preferably the barcode B.sub.P is introduced into the (optionally extended) barcode label prior to performing the amplification reaction. If the capture matrices were obtained at two or more time points, it is furthermore preferred to also introduce the barcode B.sub.T into the (optionally extended) barcode label prior to performing the amplification reaction.

    [0737] Pooling and Sequencing

    [0738] After the amplification reaction within each collection position, an aliquot of the generated sequenceable reaction products can be taken from each collection position (e.g. well) and various aliquots may be pooled within a reaction tube. Pooling is possible, as the sequence elements comprised in the sequenceable reaction products allows to identify and correlate each sequenced reaction product e.g. to the original cell-laden matrix and/or time point. The concentration of the pooled sample may be determined (e.g. by using a UV-Vis Spectrophotometer) and adjusted to be compatible with current sequencing procedures. Afterwards the adapted and pooled sample can be sequenced (e.g. by NGS).

    [0739] Sequencing Analysis

    [0740] The sequencing process will provide the sequencing data for each barcode label within the generated sequenceable reaction products (e.g. barcode library). The sample containing the pooled aliquots from all collection positions contains different barcode labels comprising the specificity information, as well as e.g. the time information, the position information (n|m), as well as the quantity information indicated by a unique molecular identifier. Thus, based on the sequencing data, an analysis algorithm can be employed to extract the mentioned information and to determine the concentration of the biomolecule of interest. In one embodiment, the following algorithm is used: [0741] 1. Identify all barcode sequence that indicated the information about the position of the compartment (position (n, m)) [0742] 2. From said barcode sequence of step 1, identify all barcode sequence that comprises the barcode sequence indicating the time information (e.g. for different time points t.sub.1, t.sub.2, . . . t.sub.x) [0743] 3. From the previously identified barcode sequence of step 2, identify all barcode sequences comprising the barcode sequence indicating the specificity of the detection molecule and thus the biomolecule of interest (B.sub.S1, B.sub.S2, . . . B.sub.Sz) to be analysed (e.g. TNF-alpha or II-6) [0744] 4. From the identified barcode sequence of step 3, count the number of UMIs that are present. This number represents the final concentration (i.e. number) of detected detection molecules at a certain time point. It is assumed, that the binding affinity of the used detection molecules is such that this number is equal to the number of bound biomolecules of interest bound to the capture molecules. Thus with step 4, the concentration of the biomolecule of interest at a certain time point (at a certain position) can be determined.

    [0745] Steps 1 to 4 may be repeated if required until the concentration of all biomolecules of interest for all time points for all positions is determined. An illustration of the corresponding data gained with the disclosed method is shown in a more general form in FIG. 4.

    II. Example 1

    [0746] According to Example 1, a method is provided for acquiring a time-resolved profile of one or more biomolecule of interest released by single or multiple cells that are provided in a matrix, preferably a three-dimensional hydrogel matrix. An overview of the process steps of Example 1 is illustrated in FIG. 8. The sequenceable reaction product of the method may be the one depicted in FIG. 3E.

    [0747] According to Example 1, one or more types of detection molecules are provided comprising a barcode label comprising following sequence elements: [0748] specificity information (B.sub.S), [0749] primer sequence (1), [0750] adaptor sequence (1), and [0751] a cleavable linker are associated during or after production of the detection molecule (e.g. commercially available antibodies).

    [0752] Furthermore, barcode sequences for quantity-, time- and position-information can be added within a collection position (e.g collection well). Sample preparation and handling of capture matrices is performed on a cell culture device, preferably a microfabricated cell culture device. Said microfabricated cell culture device important to the present disclosure as it allows to combine different sequence elements within one oligonucleotide that can be sequenced.

    [0753] The method according to example 1 comprises the steps described above in the section about the general method steps. Example 1 differs in comparison to the general method steps in following steps:

    [0754] Adding the One or More Types of Detection Molecules

    [0755] Adding the one or more types of detection molecules as described above, wherein the detection molecule comprises a barcode label comprising the following elements: [0756] a photo-cleavable linker; [0757] a primer sequence (1) for performing a polymerase chain reaction; [0758] a barcode sequence B.sub.S indicating the specificity of the detection molecule; [0759] an adaptor sequence (1).

    [0760] Optionally, Adding an Oligonucleotide to the Capture Matrix in the Compartment

    [0761] This step is not performed in Example 1.

    [0762] Addition of Information to the Barcode Label

    [0763] After collecting the desired number of capture matrices from one or more time points or one time-point and positions, the quantity- (UMI) time- and position-information can be added to the collected detection molecules, in particular the barcode label:

    [0764] An oligonucleotide containing an UMI sequence is added to the barcode label encoding the detection molecule specificity by using established methods from molecular biology well known by the person skilled in the art. For example, a polymerization extension reaction or a ligation reaction can be used to transfer the information of oligonucleotide to the barcode label. Afterwards, the barcode sequence indicating the time information and the barcode sequence indicating the position information can be added by using a PCR reaction. An illustration of the process is depicted in FIG. 8a. The addition of the quantity information (UMI) within the collection position (e.g. well) has the advantage that the number of different UMI sequences required for labeling the detection molecules can be significantly reduced. For example, if one capture matrix can be occupied by a total number of 1 million detection molecules, the UMI length does not need to be larger than 10 bp (this corresponds to a total number of 1048576=410 different UMI sequences).

    [0765] A polymerase extension/elongation and/or amplification reaction within each collection position (e.g. using a LightCycler® 1536 Multiwell Plate and a LightCycler® 1536 Instrument from LifeScience) whereas the forward primer (oligonucleotide P-fwd) contains a barcode sequence indicating the position information (B.sub.p) and the reverse primer (e.g. oligonucleotide T-rev) contains a barcode sequence representing the time information (B.sub.T) or vice versa to generate an exemplary barcode label (e.g. Oligo-P-Ab-U-T) comprising: [0766] a. the barcode sequence provided by the detection molecule (see above) [0767] b. a unique molecular identifier (UMI) [0768] c. a barcode indicating time information (B.sub.T) [0769] d. a barcode indicating position information for the compartment (B.sub.P) [0770] e. optionally, two sequences complementary to commercially available sequencing primers and adaptors from sequencing companies such as 10× Genomics, Oxford Nanopore, Pacific Biosciences, QIAGEN, Agilent Technologies and Illumina.

    [0771] In one embodiment, each well of an exemplary 1536 well plate contains one unique primer combination (e.g. pair of reverse and forward primer). For example, the well A1 contains a reverse primer that comprises a barcode sequence B.sub.T for the time-point t.sub.j and a forward primer that comprises a barcode sequence B.sub.P1 for indicating the position of the compartment (at position (m, n).sub.1) from which the capture matrix was released (position information). The well A2 might contain a reverse primer that comprises a barcode sequence B.sub.T2 for the time-point t.sub.2 and a forward primer that comprises a barcode sequence B.sub.P1 for identifying the position (m, n).sub.1. The well B1 might contain a reverse primer that comprises a barcode sequence B.sub.T1 for the time-point t, and a forward primer that comprises a barcode sequence B.sub.P2 for indicating the position (m, n).sub.2. Thus, for/positions and x time points the needed number of different primers is: n.sub.primer=I*x. This number corresponds to the number of required wells n.sub.wells=n.sub.primer. In one advantageous embodiment, the wells are pre-loaded with lyophilized components necessary for performing the PCR (e.g. by using hot-start PCR) prior to the addition of a capture matrices.

    [0772] The described above embodiment has several advantages: First, it enables the analysis of biomolecules that have been released from single cells, cell pairs and/or small cell colonies located within a 3D microenvironment in a dynamic, time-lapse manner. Second, due to the removal of the capture matrix containing the bound biomolecules of interest, the dynamic range of the detection system is large. For example, if only one capture matrix is used for the whole culture time, the capture molecules might be saturated with released biomolecules of interest within minutes to hours resulting in a limited dynamic measurement range. By using multiple capture matrices capturing only the biomolecules of interest released within a defined period, the dynamic range is increased. Third, the reduction of the reaction volume increases significantly the sensitivity of the detection mechanism as the concentration of the biomolecule of interest is higher due to the small volume reduction. Because barcode labels conjugated to detection molecules (preferably antibodies) permit a nearly unlimited number of molecular targets, analytical multiplexing capability is nearly unlimited.

    [0773] In addition, the disclosed method offers the following advantages: [0774] The method can be adapted for the detection of any biomolecule of interest, in particular protein, for which a corresponding binding molecule (i.e. detection molecules) such as an antibody is available [0775] The method provides exponential signal amplification due to the use of a polymerase chain reaction (PCR) or polymerase extension reaction which theoretically enables detection of single molecules [0776] Extremely low limit of detection (pg−fg) [0777] Suitable for small sample volumes, in particular for handling of a single cell [0778] Compatible with complex samples [0779] Fewer incubation steps than an ELISA, improved assay reproducibility [0780] Rapid time to results for whole secretome profiles [0781] Wider dynamic range than an ELISA [0782] Highly capable of multiplexing

    III. Example 2

    [0783] An overview of the process steps of Example 2 is illustrated in FIG. 6. The sequenceable reaction product of the method may be the one depicted in FIG. 3C.

    [0784] According to Example 2, one or more types of detection molecules are provided comprising a barcode label comprising following information: [0785] a barcode sequence (B.sub.S), [0786] a barcode sequences for quantity information (UMI), [0787] and the cleavable linker are added during antibody production (commercially available)

    [0788] Oligonucleotide sequences for time information and position information are added within a collection well. Antigen binding, washing and handling of capture matrices is performed on a microfabricated cell culture device. Said microfabricated cell culture device is advantageous, as it enables to combine all different information in one oligonucleotide.

    [0789] The method according to Example 2 comprises the steps described above in the section about the general method steps. Example 2 differs in comparison to the general method steps in following steps:

    [0790] Adding the One or More Types of Detection Molecules

    [0791] Adding the one or more types of detection molecules as described above, wherein the detection molecule comprises a barcode label comprising the following elements: [0792] a photo-cleavable linker; [0793] a primer sequence (1) for performing a polymerase chain reaction; [0794] a barcode sequence B.sub.S indicating the specificity of the detection molecule; [0795] a barcode sequences for quantity information (UMI); and [0796] a primer sequence (2) for performing a polymerase chain reaction.

    [0797] According to Example 2, the quantity information (UMI sequence) is part of the barcode label bound to the one or more types of detection molecules. To this end, the capture matrix containing one or more types of capture molecules, bound biomolecules of interest and one or more types of detection molecules labeled with barcode labels encode the detection molecules specificity as well as a UMI sequence is transferred into a collection position (e.g. well).

    [0798] Conjugated detection molecules having a barcode sequence for their specificity are commercially available (e.g. from Biogen) and can be easily modified with UMI sequences by a skilled person of the art to add the mentioned elements. Degenerate synthesis of oligonucleotides might be used for UMI synthesis.

    [0799] Optionally, Adding an Oligonucleotide to the Capture Matrix in the Compartment

    [0800] This step is not performed in Example 2.

    [0801] Addition of Information to the Barcode Label

    [0802] A PCR reaction within each collection well (e.g. using a LightCycler® 1536 Multiwell Plate and a LightCycler® 1536 Instrument from LifeScience) using a primer combination is performed, wherein the forward primer (oligonucleotide P-fwd) contains a barcode sequence representing the position information (Bp) and the reverse primer (oligonucleotide T-rev) contains a barcode sequence representing the time information (BT) or vice versa to generate an exemplary sequenceable reaction product (e.g. Oligo-P-Ab-U-T) comprising: [0803] a) the barcode label provided by the one or more types of detection molecules (e.g. Oligo-Ab-U), [0804] b) a time-point specific nucleotide sequence (B.sub.T), [0805] c) a position specific nucleotide sequence (B.sub.P), [0806] d) adapter sequences (e.g. two sequences complementary to commercially available sequencing primers and adaptors from sequencing companies such as 10× Genomics, Oxford Nanopore, Pacific Biosciences, QIAGEN, Agilent Technologies and Illumina.

    [0807] The direct incorporation of the UMI into the detection molecule conjugated barcode label eliminates the need for a primer elongation by reverse transcriptase reactions.

    IV. Example 3

    [0808] An overview of the process steps of Example 3 is illustrated in FIG. 7. The sequenceable reaction product of the method may be the one depicted in FIG. 3D.

    [0809] According to Example 3, one or more types of detection molecules are provided comprising a barcode label comprising following information: [0810] a barcode sequence (B.sub.S), [0811] a barcode sequences for quantity information (UMI),

    [0812] Time information is added within compartment of the cell culture device containing a capture matrix and cell-laden matrix. Position information is added within the collection well. Sample preparation and handling of the capture matrix is performed utilizing a microfabricated cell culture device. Said microfabricated cell culture device is advantageous as it enables to combine all different information within one oligonucleotide that can be sequenced.

    [0813] The method according to Example 3 comprises the steps described above in the section about the general method steps. Example 3 differs in comparison to the general method steps in following steps

    [0814] Adding the One or More Types of Detection Molecules

    [0815] The addition of one or more types of detection molecules is performed as described in Example 2.

    [0816] Optionally, Adding an Oligonucleotide to the Capture Matrix in the Compartment

    [0817] The addition of time information is done by performing an extension of the barcode label bound to the one or more types of detection molecules within the compartment of the cell culture device. After the incubation step and binding, of the biomolecules of interest the compartment containing the capture matrix as well as the cell-laden matrix is perfused with a solution that contains an oligonucleotide with the following elements: [0818] a. a barcode sequence B.sub.T, indicating a time information (e.g. time-point specific sequence) [0819] b. an adapter sequence (1) for binding to the barcode label [0820] c. a reverse primer binding sequence (2).sub.R

    [0821] In one embodiment, the solution containing the oligonucleotide might be a hybridization buffer. Due to the perfusion with the hybridization solution, the oligonucleotide binds to the barcode label (that is coupled to the one or more types of detection molecules) via the adaptor sequence (1). Afterwards, unbound oligonucleotides are washed away by perfusion with washing buffer (e.g. PBS). In a next step, the matrices are perfused with a solution containing a DNA-Polymerase such as IsoPol™ DNA Polymerase (ArcticZymes). Thus, the oligonucleotide is extended and the sequence is added to the barcode label (generating and extended barcode label). The extended barcode label contains now the following elements: [0822] a) a photo-cleavable linker, [0823] b) a primer for a polymerase chain reaction (primer sequence (1)), [0824] c) a barcode sequence B.sub.S indicating the specificity of the detection molecule (e.g. an antigen specific sequence (B.sub.S)), [0825] d) a unique molecular identifier (UMI), [0826] e) an adaptor sequence (1), [0827] f) a barcode sequence B.sub.T indicating a time information (e.g. a time-point specific sequence), and [0828] g) a primer sequence (2).

    [0829] Addition of Information to the Barcode Label

    [0830] Transferring the capture matrix from the compartment (position (m, n)) that contains the one or more types of capture molecules, bound biomolecules of interest and the barcoded one or more types of detection molecule to a pre-defined well (corresponding well to position (m, n)) of another format such as a 1536 well plate. In a preferred embodiment, this is done using the reverse flow cherry picking mechanism as disclosed. At this step, the detection molecules have coupled an extended barcode label that contains the quantity information, the specificity information as well as the time information. The matrix containing the cell(s) remains within its position. As the time information is added when the capture matrix is still positioned within said compartment of the cell culture device, the number of needed wells for generating the sequenceable reaction product is reduced from n.sub.well=I*x to n.sub.well=I.

    [0831] After collecting all detection beads from different time points and positions, the position information is added to the collected extended barcode labels that are coupled to one or more types of detection molecules. For example, this is be done by performing a PCR reaction within each collection well whereas the forward and/or reverse primer (here primer combination) might contain a barcode representing the position information.

    V. Example 4

    [0832] An overview of the process steps of Example 4 is illustrated in FIG. 9. The sequenceable reaction product of the method may be the one depicted in FIG. 3F.

    [0833] According to Example 4, one or more types of detection molecules are provided comprising a barcode label comprising following information:

    [0834] Antigen-specificity information (B.sub.S).

    [0835] Time and quantity information (UMI) is added within compartment of the cell culture device containing amplification matrix and cell-laden matrix.

    [0836] In another advantageous embodiment, the time information as well as the quantity information is added to the barcode label bound to the one or more type of detection molecules within the compartment. To this end a oligonucleotide contains a barcode sequence indicating a time information B.sub.T as well as a quantity information (UMI). An advantage is the reduced UMI library size due to combination of UMIs with B.sub.T.

    [0837] Apart from the difference above, the method according to Example 4 comprises the steps described above in the section about the general method steps.

    VI. Example 5

    [0838] An overview of the process steps of Example 5 is illustrated in FIG. 5. The sequenceable reaction product of the method may be the one depicted in FIG. 3B.

    [0839] According to Example 5, one or more types of detection molecules are provided comprising a barcode label comprising following information: [0840] Antigen-specificity (B.sub.S)/Time(B.sub.T)/Quantity (UMI) information is added during antibody production

    [0841] In another advantageous embodiment, the barcode label bound to the one or more types of detection molecule contains the specificity, the quantity and the time information thereby reducing the number of processing steps. Thus, after incubating the capture matrix and the cell-laden matrix (or matrices) and subsequent washing, the capture matrices are perfused with a solution containing one or more types of detection molecules that are labeled with the barcode label containing the specificity, quantity and time information. The capture matrices are finally transferred to a collection well where the position information is added for example by using a PCR.

    [0842] Apart from the difference above, the method according to Example 5 comprises the steps described above in the section about the general method steps.

    VII. Example 6

    [0843] The core process steps of Example 6 are illustrated in FIG. 21. The cell-laden matrix is incubated in a cell culture plate as device. The method comprises providing (e.g. generating) a cell-laden matrix, so that it is located in a compartment (e.g. well) of a cell culture plate, e.g. 96 well plate. The cell-laden matrix is positioned in a way in the compartment that the surrounding liquid(s) can be exchanged without affecting the cell-laden matrix. Cells may be encapsulated in a hydrogel plug or hemi-spheres by using a conventional pipette to provide cells positioned within a well plate. Afterwards, the following method steps are performed: [0844] Providing a capture matrix (e.g. by preparing or obtaining as disclosed herein), which comprises one or more types of capture molecules, wherein each type of capture molecule binds a biomolecule of interest; [0845] Incubating the cell-laden matrix to allow release of the one or more biomolecules of interest. As disclosed elsewhere herein, there are different options to bring the capture matrix into contact with the released biomolecule(s) of interest. The capture matrix may e.g. be present prior to or during incubation for release of the biomolecule(s) of interest or the capture matrix may be added after incubation. Addition of the capture matrix after incubation (e.g. for a pre-determined period of time) allows accumulation of the released biomolecule(s) of interest in the surrounding liquid. According to one embodiment, the capture matrix (such as a plurality of capture beads as shown in FIG. 21) is added to the compartment comprising the cell-laden matrix and the surrounding liquid after an incubation period. The one or more biomolecules of interest are allowed to bind to the one or more types of capture molecules of the capture matrix; [0846] optionally, the method comprises transferring the capture matrix to another location e.g. a different well of the same cell culture plate or to a different cell culture plate for further processing; [0847] Adding one or more types of detection molecules to the capture matrix, wherein each type of detection molecule specifically binds a biomolecule of interest, and wherein each type of detection molecule comprises a barcode label which comprises a barcode sequence (BS) indicating the specificity of the detection molecule (see step c)); [0848] preferably complete removal of unbound detection molecules e.g. by vigorous washing; [0849] Generating a sequenceable reaction product (see step d)) which comprises at least [0850] the barcode sequence (B.sub.S), and [0851] a barcode sequence (B.sub.T) for indicating a time information, and/or [0852] a barcode sequence (B.sub.P) for indicating a position information, and [0853] optionally a unique molecular identifier (UMI) sequence, [0854] wherein generation of the sequenceable reaction product preferably comprises the use of at least one oligonucleotide, optionally a primer, that is capable of hybridizing to the barcode label of the at least one type of detection molecule; and [0855] preferably, sequencing the generated reaction product (see step e)).

    [0856] It is noted that the incubation period may be selected by the skilled person in view of the cells comprised in the cell-laden matrix and the biomolecule(s) of interest. In embodiments, the incubation period is selected from the range of 1 h to 72 h, such as 4 h to 72 h. A shorter incubation period (e.g. 1 h to 24 h) may be selected for microbiological applications. For instance, a shorter incubation period may be selected for a prokaryotic cell, such as a bacterial cell, which can be comprised in the cell-laden matrix as disclosed herein. A longer incubation period (e.g. 4 h to 72 h) may be selected for other applications. For instance, a longer incubation period may be selected for a eukaryotic cell, such an animal cell, which can be comprised in the cell-laden matrix.

    [0857] The method may also comprises one or more cycles of incubation of the cell-laden matrix to allow release on the one or more biomolecules of interest and capture matrix addition in each cycle as discussed above. The repeated incubation and binding can be performed multiple times, e.g. ≥two times, ≥three times, ≥four times, or ≥five times. Suitable time intervals between cycles can be selected by the skilled person. In embodiments, the time interval between cycles is selected from ≥10 min, ≥20 min, ≥30 min, 1 h, ≥2 h, ≥3 h, ≥4 h, 5 h or more, up to days 1 d, 2 d or several days, preferably selected from the range of 30-130 min.