Disclosed are a method for analyzing an activation state of a signaling pathway in a cell or tissue through protein-protein interaction analysis, a method for selecting a tailored personal therapeutic agent and/or monitoring efficacy of a therapeutic agent using the analysis method, and a device for use therein.

The present invention provides a cell-based assay for identifying and/or quantifying anti-CD3 homodimers in a composition comprising a T cell-dependent Bispecific antibody (TDB). In some aspects, the invention T cells comprising a T cell activation responsive reporter are contacted with the TDB to detect the presence of anti-CD3 homodimers. Compositions of reporter T cells and kits are also contemplated.

The present invention provides assays and assay systems for use in spatially encoded biological assays. The invention provides an assay system comprising an assay capable of high levels of multiplexing where reagents are provided to a biological sample in defined spatial patterns; instrumentation capable of controlled delivery of reagents according to the spatial patterns; and a decoding scheme providing a readout that is digital in nature.

Methods and devices are provided herein for identifying a cell population comprising an effector cell that exerts an extracellular effect. In one embodiment the method comprises retaining in a microreactor a cell population comprising one or more effector cells, wherein the contents of the microreactor further comprise a readout particle population comprising one or more readout particles, incubating the cell population and the readout particle population within the microreactor, assaying the cell population for the presence of the extracellular effect, wherein the readout particle population or subpopulation thereof provides a direct or indirect readout of the extracellular effect, and determining, based on the results of the assaying step, whether one or more effector cells within the cell population exerts the extracellular effect on the readout particle. If an extracellular effect is measured, the cell population is recovered for further analysis to determine the cell or cells responsible for the effect.

A peptide that binds specifically to neuropilin-1 (NRP1) without binding to neuropilin-2 (NRP2) is provided. A fusion protein, a fusion antibody, small-molecule drug, a nanoparticle, or a liposome, which comprises the peptide, and a pharmaceutical composition for treating or preventing cancer or angiogenesis-related diseases, and a composition for diagnosing cancer or angiogenesis-related diseases are provided. A polynucleotide encoding the peptide that binds specifically to NRP1 and a method for screening the peptide that binds specifically to NRP1 are provided. An antibody heavy-chain constant region Fc-fused peptide binding specifically to NRP1 has the property of binding specifically to NRP1, and thus when it is administered in vivo, it accumulates selectively in tumor tissue, and widens the intercellular space between tumor-associated endothelial cells to promote its extravasation and increases its tumor tissue penetration.

Provided are methods for detecting protein interactions in a sample, the methods comprising: (a) detecting two or more polypeptides that when associated emit a first detectable signal in a first light emission spectrum; (b) contacting the two or more polypeptides with a third polypeptide conjugated to a dipole acceptor moiety that has a second light emission spectrum when excited within a light excitation spectrum, wherein the light excitation spectrum overlaps with the first light emission spectrum; and (c) detecting a second detectable signal emitted in the second light emission spectrum by the dipole acceptor moiety. Also provided are bioluminescent complexes comprising: (a) a first polypeptide conjugated to a dipole acceptor moiety, wherein the emits a first detectable signal in a first light emission spectrum.

The present invention discloses a reagent set for detecting interactions between biomolecules and their regulatory factors and applications. One reagent set disclosed in the present invention consists of three reagents named A, B and C; the reagent A is formed by connecting a biomolecule R and a biomolecule X; the reagent B contains a biomolecule L; there is an interaction between the biomolecule R and the biomolecule L, and a phase transition occurs when the biomolecule R and the biomolecule L interact; the reagent C is formed by connecting a reporter group JIA with a biomolecule named X.sub.L. Another reagent set disclosed in the present invention consists of four reagents named A, B, E and D; the reagent E is a polymer formed by E monomers, and the E monomer is obtained by connecting a monomer mc, a reporter group JIA, and a biomolecule Y.sub.C, two or more mc monomers can form a polymer; the reagent D is formed by connecting a modified protein X.sub.L and a biomolecule Y.sub.D; there is an interaction between the biomolecule Y.sub.C and the biomolecule Y.sub.D. The present invention can be used to detect the intracellular and extracellular protein interaction or even the weak interaction and has the characteristics of high visibility, simple operation, low cost, high sensitivity and wide applicability.

A method for developing capture agents for target proteins employs a compound library to find cyclic peptide sequences that bind the target protein. The target protein is also reacted with a clickable group-provider reagent to provide the protein with clickable groups. The compounds in the library are provided with complementary clickable groups that bind the clickable group on the target protein when the peptide sequences bind the target protein. In some embodiments, the cyclic peptide sequences that bind the target protein are incorporated into constructs having one or more arms that can serve as capture agents or potential treatments against the pathogens from which the target protein is derived. Some embodiments provide pharmaceutical compositions for immunoassays, diagnostics, therapeutics or the like, that employ the constructs.

The present invention is relevant to proteins and novel methods of protein evolution. The present invention further relates to methods of identifying and mapping mutant polypeptides formed from, or based upon, a template polypeptide.

The present invention provides assays and assay systems for use in spatially encoded biological assays. The invention provides an assay system comprising an assay capable of high levels of multiplexing where reagents are provided to a biological sample in defined spatial patterns; instrumentation capable of controlled delivery of reagents according to the spatial patterns; and a decoding scheme providing a readout that is digital in nature.