CANCER-KILLING CELLS

20210189340 · 2021-06-24

    Inventors

    Cpc classification

    International classification

    Abstract

    The present invention relates to an in vitro culture of haematopoietic cells, wherein said haematopoietic cells differentiate to form granulocytes characterised by the ability to kill cancer cells. The invention also relates to said granulocytes, methods for identifying said haematopoietic cells and granulocytes, compositions and kits comprising the same, as well as uses of the same for treating cancer.

    Claims

    1. An in vitro method for obtaining a haematopoietic cell suitable for use in treating cancer, said method comprising: a. contacting a cancer cell line with a granulocyte obtainable from a donor to form a test sample, and incubating said test sample; and b. obtaining a haematopoietic cell from a sample from said donor when the % of cancer cells killed in the test sample is greater than the % of cancer cells killed in a control sample, wherein the control sample comprises a cancer cell line of the same type and a granulocyte obtainable from a different donor.

    2. An in vitro method for obtaining a haematopoietic cell suitable for use in treating cancer, said method comprising: a. admixing a granulocyte obtainable from a donor with a cancer cell line to form an admixture; b. incubating said admixture; c. measuring the % of cancer cells killed in said test sample; and d. obtaining a haematopoietic cell from a sample from said donor when said granulocyte kills at least 5% of the cancer cells in the test sample.

    3. The in vitro method according to claim 1 or 2, wherein the haematopoietic cell is a haematopoietic stem cell.

    4. The in vitro method according to claim 1 or 2, wherein the haematopoietic cell is a granulocyte precursor cell, such as a common myeloid progenitor cell, a myeloblast, a N. promyelocyte, a N. myelocyte, a N. metamyelocyte, a N. band, or combinations thereof.

    5. The in vitro method according to claim 1 or 2 when the haematopoietic cell is an induced pluripotent stem cell obtainable from a somatic cell of said donor.

    6. An in vitro method for selecting a granulocyte suitable for use in treating pancreatic cancer, said method comprising: a. admixing a granulocyte with a pancreatic cancer cell line to form an admixture; b. incubating said admixture; c. measuring the % of pancreatic cancer cells killed in said admixture; and d. selecting a granulocyte that kills at least 5% of the pancreatic cancer cells in the admixture.

    7. An in vitro method for selecting a granulocyte that selectively kills a cancer cell, said method comprising: a. contacting a cancer cell line with a granulocyte obtainable from a donor to form a test sample, and incubating said test sample; and b. selecting said granulocyte as selective for a cancer cell when the % of cancer cells killed in the test sample is greater than the % of non-cancer cells killed in a control sample, wherein the control sample comprises a non-cancer cell line and a granulocyte obtainable from the same donor.

    8. An in vitro method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: a. measuring the cell surface charge of a granulocyte obtainable from a donor; and b. obtaining a haematopoietic cell from a sample from said donor when said granulocyte has a more positive cell surface charge when compared to a control granulocyte.

    9. An in vitro method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: a. measuring the concentration of granulocytes having a positive cell surface charge in a sample obtainable from a donor; and b. obtaining a haematopoietic cell from a sample from said donor when the concentration of said granulocytes having a positive cell surface charge is greater than the concentration of granulocytes having a positive cell surface charge in an otherwise identical control sample from a different donor.

    10. An in vitro method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: a. measuring the cell surface charge of a granulocyte obtainable from a first donor; b. identifying a granulocyte obtainable from said first donor having a more positive cell surface charge when compared to a control granulocyte; c. measuring the concentration of granulocytes identified in step b.; d. comparing the concentration of said granulocytes measured in step c. with the concentration of granulocytes obtainable from a second (or further) donor, wherein the granulocytes from said second (or further) donor have a more positive cell surface charge when compared to the control granulocyte; and e. obtaining a haematopoietic cell from a sample from said first donor when the comparison identifies a greater concentration of said granulocytes obtainable from said first donor when compared to the concentration of said granulocytes obtainable from said second (or further) donor.

    11. The in vitro method according to any one of claims 8-10, wherein the granulocyte is contacted by a negatively charged nanoprobe or nanoparticle, preferably wherein said granulocyte is isolated following said contacting.

    12. The in vitro method according to any one of the preceding claims, wherein the cancer cell line(s) is one or more selected from: a pancreatic cancer cell line, a liver cancer cell line, an oesophageal cancer cell line, a stomach cancer cell line, a cervical cancer cell line, an ovarian cancer cell line, a lung cancer cell line, a bladder cancer cell line, a kidney cancer cell line, a brain cancer cell line, a prostate cancer cell line, a myeloma cancer cell line, a non-Hodgkin's lymphoma (NHL) cell line, a larynx cancer cell line, a uterine cancer cell line, or a breast cancer cell line.

    13. The in vitro method according to any one of the preceding claims, wherein the cancer cell line is a pancreatic cancer cell line.

    14. The in vitro method according to any one of the preceding claims, wherein the cancer cell line is a pancreatic ductal adenocarcinoma cell line, preferably wherein the cancer cell line is a PANC-1 cell line.

    15. The in vitro method according to any one of the preceding claims, wherein the granulocyte is a neutrophil.

    16. The in vitro method according to any one of claim 6-7 or 12-15 further comprising discarding granulocytes that kill less than 5% of the cancer cells in the admixture.

    17. The in vitro method according to any one of claim 6-7 or 12-16, further comprising obtaining a haematopoietic cell from a sample from said donor from whom the selected granulocyte is obtainable.

    18. A haematopoietic cell or in vitro cell culture thereof obtainable by the method of any one of claim 1-5, 8-15 or 17, preferably wherein the haematopoietic cell has a positively charged cell surface.

    19. A granulocyte or in vitro cell culture thereof obtainable by the method of any one of claim 6-7 or 12-17 or differentiated from the haematopoietic cell or in vitro cell culture thereof according to claim 18, preferably wherein the granulocyte has a positively charged cell surface.

    20. An in vitro cell culture of haematopoietic cells, wherein said haematopoietic cells differentiate to form granulocytes characterised by: a. a surface potential defined by an electrophoretic mobility of at least 1.0 μm.Math.cm/volt.Math.sec and/or a density of greater than 1.077 g/ml; and b. the ability to kill cancer cells.

    21. A pharmaceutical composition comprising: a. the haematopoietic cell or in vitro cell culture thereof according to claim 18, the granulocyte or in vitro cell culture thereof according to claim 19 or the in vitro cell culture of haematopoietic cells according to claim 20; and b. a granulocyte-macrophage colony-stimulating factor (GM-CSF), a granulocyte colony-stimulating factor (G-CSF), a growth hormone; serotonin, vitamin C, vitamin D, glutamine (Gln), arachidonic acid, AGE-albumin, an interleukin, TNF-alpha, Flt-3 ligand, thrombopoietin, foetal bovine serum (FBS), or combinations thereof.

    22. A kit comprising: a. the haematopoietic cell or in vitro cell culture thereof according to claim 18, granulocyte or in vitro cell culture thereof according to claim 19, the in vitro cell culture of haematopoietic cells according to claim 20, or pharmaceutical composition according to claim 21; and b. instructions for use of same in medicine.

    23. The haematopoietic cell or in vitro cell culture thereof according to claim 18, granulocyte or in vitro cell culture thereof according to claim 19, the in vitro cell culture of haematopoietic cells of claim 20, pharmaceutical composition according to claim 21, or kit according to claim 22, for use in treating cancer.

    24. Use of the haematopoietic cell or in vitro cell culture thereof according to claim 18, granulocyte or in vitro cell culture thereof according to claim 19, the in vitro cell culture of haematopoietic cells according to claim 20, pharmaceutical composition according to claim 21, or kit according to claim 22 in the manufacture of a medicament for treating cancer.

    25. A method for treating cancer comprising: administering to a subject in need thereof the haematopoietic cell or in vitro cell culture thereof according to claim 18, granulocyte or in vitro cell culture thereof according to claim 19, the in vitro cell culture of haematopoietic cells according to claim 20, or pharmaceutical composition according to claim 21.

    26. The haematopoietic cell or in vitro cell culture thereof, granulocyte or in vitro cell culture thereof, pharmaceutical composition, or kit for use, use or method according to any one of claims 18-25, wherein the cancer is a solid tumour cancer.

    27. The haematopoietic cell or in vitro cell culture thereof, granulocyte or in vitro cell culture thereof, or pharmaceutical composition for use, use or method according to any one of claims 18-26, wherein the cancer is one or more of: pancreatic cancer, liver cancer, oesophageal cancer, stomach cancer, cervical cancer, ovarian cancer, lung cancer, bladder cancer, kidney cancer, brain cancer, prostate cancer, myeloma cancer, non-Hodgkin's lymphoma (NHL), larynx cancer, uterine cancer, or breast cancer.

    28. A cell bank comprising the haematopoietic cell or in vitro cell culture thereof according to claim 18, granulocyte or in vitro cell culture thereof according to claim 19, the in vitro cell culture of haematopoietic cells according to claim 20, or pharmaceutical composition according to claim 21.

    Description

    FIGURES

    [0416] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying Figures, in which:

    [0417] FIG. 1 shows cytotoxicity results of Donor Derived Neutrophils (DDNs) from different donors and at different effector to target cell ratios (MTT assay). Differential levels of CKA between donors is maintained at higher effector:target cell ratios. Effector:DDNs; Target:HeLa cells.

    [0418] FIG. 2 shows cytotoxicity results of three CD34+ Stem Cell Derived Neutrophil populations from different donors and at different effector to target cell ratios. Results demonstrate that Stem Cell Derived Neutrophils from different donors have differential CKA. Effector:SCDNs; Target:HeLa cells and PANC-1 (pancreatic cancer).

    [0419] FIG. 3 shows cytotoxicity results of Donor Derived Neutrophils (DDNs) from different donors and at different effector to target cell ratios (xCELLigence Assay). Differential levels of CKA between donors is maintained at higher effector:target cell ratios. Effector:DDNs; Target:HeLa cells.

    [0420] FIG. 4 shows cytotoxicity results of fresh Donor Derived Neutrophils against different cancer cell types and at different effector to target cell ratios. Results demonstrate that DDNs from different donors have differential CKA and have higher CKA against pancreatic cancer cells. Effector:DDNs; Target:HeLa cells (cervical cancer) and PANC-1 cells (pancreatic cancer).

    [0421] FIG. 5 shows selective cytotoxicity of Donor Derived Neutrophils for cancer cell types compared to non-cancer cells and at different effector to target cell ratios. Results demonstrate that DDNs that kill cancer cells have minimal impact on non-cancer cells, confirming selectivity. Effector:DDNs; Target:HeLa cells (cervical cancer) and PANC-1 cells (pancreatic cancer) and MCF-12F (non-cancer cells, normal breast epithelium).

    [0422] FIG. 6 shows cytotoxicity results of CD34+ Stem Cell Derived Neutrophil populations (derived from cord blood stem cells) from five different cultures and at different effector to target cell ratios. Results were generated with the MTT assay and demonstrate that ex vivo generated neutrophils have differential CKA. Effector:SCDNs; Target:HeLa cells.

    [0423] FIG. 7 shows cytotoxicity results of three CD34+ Stem Cell Derived Neutrophil populations against different cancel cell types and at different effector to target cell ratios. Results demonstrate that SCDNs from different donors have differential CKA and have higher CKA against pancreatic cancer cells. Effector:SCDNs; Target:HeLa cells (cervical cancer) and PANC-1 cells (pancreatic cancer).

    [0424] FIG. 8 shows cytotoxicity results of three CD34+ Stem Cell Derived Neutrophil populations from different donors and at different effector to target cell ratios. Results demonstrate that Stem Cell Derived Neutrophils from different donors have differential CKA. Effector:SCDNs; Target:HeLa cells (cervical cancer) and PANC-1 cells (pancreatic cancer).

    [0425] FIG. 9 shows cytotoxicity results of three CD34+ Stem Cell Derived Neutrophil populations from different donors (LC267, LC268, LC269) and at different effector to target cell ratios. Results demonstrate that Stem Cell Derived Neutrophils from different donors have selective cytotoxicity. Effector:SCDNs; Target:HeLa cells (cervical cancer), PANC-1 cells (pancreatic cancer) and MCF-12F cells (non-cancer cells, normal breast epithelium).

    [0426] FIG. 10 shows cytotoxicity results of three CD34+ Stem Cell Derived Neutrophil populations from different donors (LC252, LC253, LC254) and at different effector to target cell ratios. Results demonstrate that Stem Cell Derived Neutrophils from different donors have selective cytotoxicity. Effector:SCDNs; Target:HeLa cells (cervical cancer), PANC-1 cells (pancreatic cancer) and MCF-12F cells (non-cancer cells, normal breast epithelium).

    [0427] FIG. 11 shows cytotoxicity results of three CD34+ Stem Cell Derived Neutrophil cultures together with cytotoxicity results of Donor Derived Neutrophils from the same donor and at different effector to target cell ratios. SCDNs and DDNs from the same donor have similar CKA levels. A similar CKA relationship between DDNs and SCDNs was maintained at different effector to target cell ratios for donor LC253. Effector:SCDNs and DDNs; Target:HeLa cells (cervical cancer).

    [0428] FIG. 12 shows cytotoxicity results of three CD34+ Stem Cell Derived Neutrophil cultures together with cytotoxicity results of fresh Donor Derived Neutrophils from the same donor and at different effector to target cell ratios. SCDNs and DDNs have similar CKA levels. The same CKA relationship between DDNs and SCDNs was maintained at different effector to target cell ratios for donor LC253. Effector:SCDNs and DDNs; Target:HeLa cells (cervical cancer).

    [0429] FIG. 13 shows a comparison of the cytotoxicity of naturally derived and stem cell derived neutrophils over time. The highest CKA (donor LC269) is maintained between DDNs and SCDNs. Effector:SCDNs and DDNs (three different SCDN and DDN cultures); Target:HeLa cells (cervical cancer).

    EXAMPLES

    Example 1

    Recruitment of Donors

    [0430] Donors are pre-selected based on the probability of having neutrophils exhibiting high levels of Cancer Killing Activity (CKA) in a CKA assay described in Example 2. Pre-selection criteria include: [0431] no serious medical or psychiatric condition that effecting provision of consent or sample collection; [0432] no personal or family history of the cancer(s) being targeted for therapy; [0433] no history of chemotherapy or radiation therapy within three months prior to the sampling date; [0434] aged 18-24; [0435] optionally male (without wishing to be bound by theory, neutrophils from males are believed to exhibit the highest levels of CKA when tested in the CKA assay); and [0436] optionally blood groups 0 or rhesus negative.

    [0437] White Blood Cells (WBCs) are collected by drawing approximately 18 ml of human blood from a donor. The blood is split into three BD Vacutainer™ CPT tubes and centrifuged at 175×g for 35 minutes at 23° C. The mononuclear cell (MN) layer is collected and transferred to a 15 ml conical tube. The MN cells are centrifuged at 420×g for 5 minutes at 23° C., and washed with 10 ml Dulbecco's Modified Eagle's Medium (DMED) (Invitrogen, Carlsbad, Calif.)+10% foetal bovine serum (FBS) (Sigma. St. Louis, Mo.). Cells are counted and resuspended in medium to a final concentration of 1.6×10.sup.6 cells/ml.

    Example 2

    Testing CKA of Extracted Granulocytes in a CKA Assay

    [0438] Cells are cultured in DMEM+10% FBS in a T25 flask to 80% confluence. The cell line is grown and maintained at 37° C., 8% CO.sub.2, in T75 cm.sup.2 cell culture flasks in DMEM supplemented with the following ingredients: 10% volume/volume FBS, penicillin (Sigma. St. Louis, Mo.), streptomycin (Sigma. St. Louis, Mo.), and supplemental L-glutamine (Sigma. St. Louis, Mo.). Cultured pancreatic cancer cells (e.g. Capan-2, ATCC HTB-80; Panc 10.05, ATCC CRL-2547; CFPAC-1, ATCC CRL-1918; HPAF-II, ATCC CRL-1997; SW 1990, ATCC CRL-2172; BxPC-3, ATCC CRL-1687; AsPC-1, ATCC CRL-1682; ATCC® TCP-1026TH; SW1990, ATCC CRL-2172; SU.86.86, ATCC CRL-1837; BXPC-3, ATCC CRL-1687; Panc 10.05, ATCC CRL-2547; MIA-PaCa-2, ATCC CRL-1420; PANC-1, ATCC CRL-1469; or ATCC® TCP-2060TH commercially available from the American Type Culture Collection—United Kingdom (U.K.), Guernsey, Ireland, Jersey and Liechtenstein, LGC Standards, Queens Road, Teddington, Middlesex TW11 0LY, UK) are split and passaged before reaching 70% surface confluence in culture flasks.

    [0439] Cells are trypsinised, harvested and counted with Trypan Blue. Assay plates (24-well) are seeded with 8×10.sup.4 pancreatic cancer cells (e.g. pancreatic ductal adenocarcinoma cells) per well in 24-well flat bottom plates. Plates are incubated at 37° C. in 5% CO.sub.2 for 24 hours. Cells are labelled with 2.5 μM CellTracker™ Green for 45 minutes. Fresh medium is added to cells and they are returned to a CO.sub.2-incubator.

    [0440] The CKA assay is carried out by adding 500 μl of MN cell suspension (8×10.sup.5 granulocytes) to each well in which the pancreatic cancer cells are grown for 24 hours. The cells are mixed and placed in an incubator in 5% CO.sub.2 for 24 hours at 39° C. After a 24-hour incubation, cells are harvested by trypsinisation and centrifuged. Cells are resuspended in 100 μl cold phosphate-buffered saline (PBS), and 125 μl 0.4% Trypan Blue subsequently added. Cells are counted under microscope (using phase contrast and fluorescence microscopy).

    [0441] Granulocytes (e.g. neutrophils) capable of killing at least 70% or at least 80% of the cancer cells (i.e. having at least 70% CKA or 80% CKA, respectively) in the assay are considered particularly suitable for use in treating cancer.

    Example 3

    Testing Surface Potential of Haematopoietic Cells and Neutrophils

    [0442] Electrophoresis is used to investigate the surface potential variation in haematopoietic cells (e.g. haematopoietic stem cells, and/or precursor cells) and neutrophils by measuring the electrophoretic mobility. The suspended cells are collected from culture, by mechanical detachment and collection from the culture substrate. Collected cells are redistributed in an electrophoresis buffer solution containing 10 mM Tris-HCl and 291 mM glucose, and are introduced into a rectangular glass electrophoresis chamber. 200V DC is applied across the electrophoresis chamber. The electrophoretic velocity of cells, u, is measured by recording the time needed for cells passing a fixed length with 3 mA under a microscope with a CCD camera. The electrophoretic mobility, p, is calculated by μ=ugS/I, where g is the conductivity of medium, S is the cross-sectional area of the electrophoresis chamber, and/is the current. For each condition typically at least 9 readings are performed to calculate cell electrophoretic mobility.

    Example 4

    [0443] Extracting Haematopoietic Stem Cells from Peripheral Blood

    [0444] Upon giving consent the donors are given a granulocyte-colony stimulating factor (G-CSF) and/or a granulocyte-macrophage colony-stimulating factor (GM-CSF), e.g. Neupogen® (commercially available from Amgen Inc. USA) to help harvest peripheral haematopoietic stem cells with minimal possible discomfort to donors. Cell surface polypeptide markers are used for identifying long-lasting multipotent stem-cells. Suitably markers may include CD 34.sup.+, CD59.sup.+, Thy1.sup.+, CD38.sup.low/−, C-kit.sup.−/low, and lin.sup.−.

    Example 5

    Expansion and Differentiation of Haematopoietic Cells

    [0445] The haematopoietic cells (e.g. haematopoietic stem cells) are stimulated using a supernatant growth factor suspension, to either develop more stem cells or differentiate into precursor cells (e.g. myeloid or granulocyte progenitor cells) or granulocytes. Suitable neutrophil synthesis methods are disclosed in Lieber et al, Blood, 2004 Feb. 1; 103(3):852-9, and Choi et al, Nat. Protoc., 2011 March; 6(3):296-313.

    [0446] The protocol is composed of four major stages: [0447] culturing and proliferation of haematopoietic cells; [0448] short-term expansion of multipotent myeloid progenitors with a high dose of granulocyte-macrophage colony-stimulating factor (GM-CSF), a granulocyte colony-stimulating factor (G-CSF), a human growth hormone (HGH); serotonin, vitamin C, vitamin D, glutamine (Gln), arachidonic acid, AGE-albumin, interleukin-3 (IL-3), interleukin 8 (IL-8), Interleukin-4 (IL-4), Interleukin-6 (IL-6), interleukin-18 (IL-18), TNF-alpha, Flt-3 ligand, thrombopoietin, foetal bovine serum (FBS), or combinations thereof; and [0449] directed differentiation of myeloid progenitors into neutrophils, eosinophils, dendritic cells (DCs), Langerhans cells (LCs), macrophages and osteoclasts.

    Example 6

    Preparation of Cell Banks

    [0450] Haematopoietic stem cells, granulocyte precursor cells and granulocytes obtainable therefrom, are cryogenically frozen and stored in appropriate cell banks.

    Example 7

    Use in Patients for Treating Solid Tumours

    [0451] Stored haematopoietic cells (e.g. haematopoietic stem cells or granulocyte precursor cells obtainable therefrom), and granulocytes (e.g. neutrophils) differentiated therefrom are matched to cancer patients based on their cancer type, blood type (ABO, rhesus and HLA), and/or genetics. Patients may also be matched based on human leukocyte antigen (HLA) similarity.

    [0452] Patients are treated using: [0453] IV infusion of haematopoietic cells (including haematopoietic stem cells, and granulocyte precursor cells) together with granulocyte-colony stimulating factor, human growth hormone, serotonin, and interleukin into the patient; or [0454] IV infusion of stimulated granulocyte precursor cells (obtainable from haematopoietic stem cells) into the patient. Without wishing to be bound by theory, it is believed that said cells naturally differentiate into granulocytes (e.g. neutrophils) having a high CKA in a CKA assay in vivo; or [0455] direct IV infusion of granulocytes (e.g. neutrophils) having a high CKA in a CKA assay which have been differentiated from haematopoietic cells (e.g. haematopoietic stem cells).

    [0456] Typically, cells are infused once weekly for 8 weeks with a cell volume of 2×10.sup.11 administered per week. Progress of the therapy is monitored and dosing is adapted accordingly.

    Example 8

    [0457] Treatment of a Patient with Pancreatic Cancer

    [0458] Mary is diagnosed with metastatic pancreatic ductal adenocarcinoma (PDAC) at age 69. Surgery is no longer an option (un-resectable), gemcitabine inadequate in preventing disease progression, and Abraxane or Folfirinox unsuitable on her Oncologist's recommendation due to the side-effects that will render her incapable of enjoying the time she has left with her family. Mary's prognosis is 3-6 months to live, and she is desperate to live long enough to see her newly-expected grandchild.

    [0459] Mary is invited to try Leukocyte Infusion Therapy (LIFT). To assess the potential suitability of the therapy, the hospital extracts 20 ml of blood from Mary and sends it for analysis using the Cancer Killing Activity Assay, the assay identifies that the pancreatic cancer killing activity of her granulocytes is less than 5%. Such a low reading demonstrates the inadequacy of her own innate immune system to fight off her cancer which will kill her if the efficacy of the granulocytes in her body is not improved.

    [0460] Mary's patient notes and assay result are used to find a suitable cancer killing granulocyte match. Mary is blood group A. Mary's profile is processed using a cell database for a cell bank and suitable granulocytes (that prior to cryogenic freezing exhibit a 70-90% Cancer Killing Activity (CKA) in the Cancer Killing Activity assay of Example 2) are identified. Cryogenically freezing granulocytes helps preserve the CKA and so the cells are able to be dispatched directly to the hospital (The Royal Marsden) with no further testing. Mary is due to visit that week for her first treatment. The hospital appropriately stores the cells. Mary receives her first infusion of 2×10.sup.9 granulocytes having CKA on the 13.sup.th December under close supervision. Mary is invited back to the hospital 3 days later where she is given an ultrasound scan which reveals significant tumour lysis and no signs of tumour lysis syndrome. The medical team decide to increase the granulocyte dose incrementally over 3 successive treatment sessions until it reaches 2×10.sup.11.

    [0461] An ultrasound is carried out on the 17.sup.th January; one week after the 4-week course of four treatments is completed, and shows complete tumour destruction and conversion into scar tissue with good healing taking place. 20 ml of Mary's blood is taken: i) to assess the presence of metastatic cancer cells in her blood (to confirm complete clearance of the cancer) alongside a biopsy; and ii) to test the Cancer Killing Activity of Mary's granulocytes (to indicate risk of remission). Mary receives regular check-ups first monthly and then 6-monthly.

    [0462] Two years later a new tumour is discovered on Mary's pancreas. Her clinicians treat the tumour with radiotherapy and administer a single high dose of LIFT to ensure destruction of any cancer cells that may be present in the blood. Mary enjoys the life that is given back to her and the family she gets to see grow up.

    [0463] After the therapy, the haematopoietic cells (e.g. haematopoietic stem cells) from the cell bank are stimulated to produce more granulocytes (having desired CKA as tested using the assay of Example 2) to replenish stocks. Thus sufficient stock of the required granulocytes for similar patient situations is ensured.

    Example 9

    MTT “CKA Assay”

    [0464] MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), a yellow tetrazole which is positively charged and readily penetrates viable eukaryotic cells. Viable cells with active metabolism convert MTT into a purple coloured formazan product (1(E,Z)-5-(4,5-dimethylthiazol-2-yl)-1,3-diphenylformazan) through NAD(P)H-dependent oxidoreductase mitochondrial enzymes, with an absorbance maximum near 570 nm. When cells die, they lose the ability to convert MTT into formazan, thus colour formation serves as a useful and convenient marker of only the viable cells. A solubilization solution is added to dissolve the insoluble purple formazan product into a coloured solution. The absorbance of this coloured solution can be quantified by measuring at wavelength 570 nm by a spectrophotometer. The absorption of a reference wavelength of 690 nm is subtracted from the absorption of the 570 nm wavelength. Therefore, the MTT assay was used to measure how many live cells remained as a way to determine Cancer Killing Activity (CKA)—cytotoxicity to cancer cells.

    Method for Preparing Hela Target Cells

    Day 1:

    [0465] 1) HeLa cells (a robust type of cervical cancer cell) were cultured and harvested when they reached log phase
    2) 10000 HeLa cells (target cells) were added to each well of a 96 Flat bottom plate at a final volume of 100 uL
    3) Target cells were left to adhere overnight before leukocyte (effector cells) addition and all experimental conditions were set in triplicates

    Day 2:

    [0466] 4) Effector cells were added to the target cells at different ratios (e.g. 1:1, 5:1, 10:1, 50:1, effector to target cells)
    5) The cells were left to incubate for 16-24 hours at 37° C.
    6) Target cells alone and target cells in the presence of Triton X were also plated in triplicates as controls for 0% and 100% cytotoxicity, respectively.

    [0467] After the desired incubation time: [0468] 1) The wells were washed with PBS twice to remove effector cells and dead target cells [0469] 2) MTT solution was prepared by dissolving the kit solution 10 times with culture medium, i.e: for 100 wells: take 1000 uL (1 mL) of MTT stock (provided in the kit) and 9000 uL (9 mLs) of culture medium (RPMI-1640) added [0470] 3) Add 100 ul/well of the prepared MTT solution at step 2 [0471] 4) This was incubated for 4 h [0472] 5) MTT Solution was removed from all wells and 100 ul/well of the solvent was added (provided in the kit). [0473] 6) The formazan crystals were solubized when needed by pipetting and the plate read at 570 and 690 nm. Background absorbance measured at 690 nm was subtracted from absorbance measured at 570 nm.

    Demonstrating Variable CKA in Donor Neutrophils

    [0474] Leukocyte cones from anonymous blood donors were selected and neutrophils were isolated by Ficoll-Hypaque separation (Oh H, Siano B, Diamond S. Neutrophil Isolation Protocol. Journal of Visualized Experiments: JoVE. 2008; (17):745). These neutrophils were used in the aforementioned MTT assay in ratios of effector to target cell of 1:1, and 5:1.

    [0475] FIG. 1 shows the percentage cytotoxicity recorded by MTT for the different donors. There is a difference between the donors at ratios 1:1 and 5:1. In conclusion, the MTT assay, is able to demonstrate differences in CKA between neutrophils from different donors.

    Example 10

    Demonstrating CKA of Stem Cell Derived Neutrophils

    [0476] Culturing Neutrophils from CD34+ Stem Cells

    [0477] We cultured neutrophils from umbilical cord blood derived stem cells expressing the CD34 protein, using the protocol as described by Timmins N E, Palfreyman E, Marturana F, Dietmair S, Luikenga S, Lopez G, et al. Clinical scale ex vivo manufacture of neutrophils from hematopoietic progenitor cells. Biotechnology and bioengineering. 2009; 104(4):832-40.

    [0478] The resulting cultures were tested for neutrophil content using CD11b+ and CD15 markers by Fluorescence-activated cell sorting (FACS). We also measured the production of Reactive Oxygen Specimens (ROS), more specifically the production of superoxide anion (O.sub.2—) by use of the nitroblue tetrazolium (NBT) assay (kit and protocol commercially-available from Sigma-Aldrich, Catalogue No. 840W-1KT).

    [0479] Since differences in ROS activity were found based on the age of the stem cell derived neutrophils (data not shown), we enumerated three stem cell batches on the same day for consistency/comparability. The results of the FACS derived counting of the proportion of CD11 b+ and CD15+ cells are listed in Table 1.

    TABLE-US-00001 TABLE 1 Percentage of CD11b+/CD15+ positive neutrophils CD11b+ CD15+ CD34+ FACS on 26 Sep. 2017 (% of all cells) (% of all cells) CD34+ 14 Sep. 2017 batch 008A 77.8 4.45 (12 days in culture) CD34+ 14 Sep. 2017 batch 709A 76.0 5.1 (12 days in culture) CD34+ 14 Sep. 2017 915 69.2 10.0 (12 days in culture)

    Demonstrating CKA of CD34+ Derived Neutrophils

    [0480] Stem cell derived neutrophils (batches 008A, 709A and 915) were used as effector cells in the CKA MTT assay using HeLa target cells (see Example 9). The effector to target cell ratio is based on CD11b+/CD15+. The results are summarized in FIG. 2, which demonstrate that CD34+ stem cell derived neutrophils demonstrate cytotoxicity in a HeLa cell CKA assay and that the results are different between different donors. Batch 008A shows consistently lower cytotoxicity than batches 915 and 709A up to 10:1 effector to target ratio, despite being prepared at the same time as the other batches and cultured in the same way.

    [0481] The results demonstrate that stem cells from different donors can a) be differentiated in vitro to produce neutrophils that demonstrate cancer killing abilities, and b) that this cancer killing activity varies by the source donor.

    [0482] The results support the fact that the cancer killing activity (CKA) by the innate immune system varies by individual and that the same innate variance in CKA seen in neutrophils taken directly from donors via leukocyte cones, is also shown in a donor's stem cells. By selecting donors with proven high cancer killing activity of their innate immune system, and using their haematopoietic cells (i.e. haematopoietic stem cells) for ex vivo expansion and differentiation, a cell bank can be created with leukocytes with high cancer killing activity to be used in the treatment of cancer.

    Example 11

    [0483] xCELLigence “CKA Assay”

    [0484] The ACEA Biosciences xCELLigence RTCA DP Analyzer System® was used and the manufacturer's instructions were followed. The xCELLigence System is a real-time cell analyser, allowing for label-free and dynamic monitoring of cellular phenotypic changes continuously by measuring electrical impedance. The system measures impedance using interdigitated gold microelectrodes integrated into the bottom of each well of the tissue culture E-Plates. Impedance measurements are displayed as Cell Index (CI) values, providing quantitative information about the biological status of the cells, including viability. Impedance-based monitoring of cell viability correlates with cell number and MTT-based readout. The kinetic aspect of impedance-based cell viability measurements provides the necessary temporal information when neutrophils are used to induce cytotoxic effects. In particular, the xCELLigence System can also pinpoint the optimal time points when the neutrophils achieve their maximal effect (where such data is desired), as indicated by the lowest CI values, in cytotoxicity and cell death assays. Typically, 6,000 cancer cells (HeLa or PANC-1) or healthy, non-cancerous cells (MCF-12F) are placed in the bottom of a 16 well plate (the system can read up to 3 plates simultaneously). For the first few hours after cells have been added to a well there is a rapid increase in impedance. This is caused by cells falling out of suspension, depositing onto the electrodes, and forming focal adhesions. If the initial number of cells added is low and there is empty space on the well bottom, cells will proliferate, causing a gradual yet steady increase in Cl. When cells reach confluence the CI value plateaus, reflecting the fact that the electrode surface area that is accessible to bulk media is no longer changing. At this point, which is called the ‘normalization point’, the neutrophils are added (typically in varying effector:target ratios). The percentage of cytolysis is readily calculated using a simple formula: Percentage of cytolysis=((Cell Index.sub.no effector−Cell Index.sub.effector)/Cell Index.sub.no effector)×100.

    [0485] The assay was typically carried out for up to 70 hours and was used in generating the results presented in Examples 12-20. Results presented in Examples 12-19 are maximal % cytolysis achieved during the assay for each cell type.

    [0486] The ratios shown in FIGS. 3-13 are the ratios of effector (e.g. neutrophil) to target (e.g. cancer cell). Typically ratios of 5:1 or 10:1 neutrophils to cancer cells were used.

    Example 12

    Demonstrating Variable CKA in Donor Derived Neutrophils

    [0487] FIG. 3 shows the maximum percentage cytotoxicity recorded by xCELLigence assay for different donors. This assay also shows a difference between the donors at ratios 1:1 and 5:1 (of neutrophils to HeLa cells). In conclusion, the xCELLigence assay is also able to demonstrate differences in CKA between neutrophils from different donors and that this was consistent over different granulocyte to cancer cell ratios.

    [0488] The assay was carried out for up to 40 hours.

    Example 13

    Demonstrating CKA of Donor Derived Neutrophils on Different Cancer Cell Types

    [0489] Neutrophils isolated from five different donors were tested for CKA against both HeLa cells (cervical cancer) and PANC-1 cells (pancreatic cancer).

    [0490] FIG. 4 shows the maximum percentage cytotoxicity recorded by the CKA assay (xCELLigence assay) against each cancer cell type and for the different donors. The percentage cytotoxicity against pancreatic cancer cells was higher, which was surprising given that pancreatic cancer is typically one of the most difficult cancers to treat. Again, Donor Derived Neutrophils (DDNs) from different donors were shown to have differential CKA.

    Example 14

    Demonstrating the Selectivity of Donor Derived Neutrophil CKA for Cancer Cells

    [0491] Neutrophils isolated from five different donors were tested for CKA against both HeLa cells (cervical cancer), PANC-1 cells (pancreatic cancer) as well as non-cancer MCF-12F cells (normal breast epithelial cells).

    [0492] FIG. 5 shows the maximum percentage cytotoxicity recorded by the CKA assay (xCELLigence assay) for neutrophils from each donor against HeLa and PANC-1 cancer cell lines versus a MCF-12F non-cancer cell line. Advantageously, DDNs were highly selective for cancer cells showing minimal impact on non-cancer cells.

    Example 15

    [0493] Culturing Neutrophils from CD34+ Stem Cells

    [0494] Further results from culturing neutrophils from umbilical cord blood derived stem cells is presented in Table 2, which shows that neutrophils can be generated from CD34+ haematopoietic stem cells isolated from cord blood. CD34+ is a haematopoietic stem cell marker. CD11b and CD15 are mature neutrophil markers.

    TABLE-US-00002 TABLE 2 Percentage of CD11b+/CD15+ positive neutrophils FACS results FACS results Days in CD11b+/ Days in CD11b+/ culture CD34+ CD15+ culture CD34+ CD15+ Batch 1 14 1.32% .sup. 61% 18 0.94% 74.3% Batch 2 8 4.21% 40.3% 12   3% 60.3%

    Example 16

    Demonstrating CKA of CD34+ Stem Cell Derived Neutrophils (SCDNs)

    [0495] Results were obtained via the xCELLigence assay with further populations of CD34+ Stem Cell Derived Neutrophils (FIG. 6), and were consistent with results obtained via the MTT assay as described above. SCDNs (generated ex vivo) were again shown to have differential CKA, with culture 5 representing low CKA neutrophils and culture 1 representing high CKA neutrophils.

    Example 17

    Demonstrating CKA of Stem Cell Derived Neutrophils on Different Cancer Cell Types

    [0496] CD34+ Stem Cell Derived Neutrophils isolated from three different donors were tested for CKA against both HeLa cells (cervical cancer) and PANC-1 cells (pancreatic cancer).

    [0497] FIG. 7 shows the maximum percentage cytotoxicity recorded by the CKA assay (xCELLigence assay) against each cancer cell type and for donors LC267, LC268 and LC269. Similar to the results obtained for DDNs (see Example 14), the percentage cytotoxicity against pancreatic cancer cells was higher than that observed for HeLa cell (at both 5:1 and 10:1 effector to target cell ratios). SCDNs from different donors were also shown to have differential CKA. The assay was carried out for up to 45 hours.

    [0498] Similar results were obtained for SCDNs obtained from donors LC252, LC253 and LC254 (FIG. 8).

    Example 18

    Demonstrating the Selectivity of Stem Cell Derived Neutrophils CKA for Cancer Cells

    [0499] Neutrophils derived from CD34+ stem cells of three different donors were tested for CKA against both HeLa cells (cervical cancer), PANC-1 cells (pancreatic cancer) as well as non-cancer MCF-12F cells (normal breast epithelial cells).

    [0500] FIG. 9 shows the maximum percentage cytotoxicity recorded by the CKA assay (xCELLigence assay—carried out for up to 45 hours) against each cancer cell type and non-cancer cell type for donors LC267, LC268 and LC269. Advantageously, SCDNs were highly selective for cancer cells showing minimal impact on non-cancer cells. Similarly to FIG. 3 showing DDN from the same donors, SCDNs from donor LC269 had the highest CKA with LC268 second, and LC267 showing the lowest CKA. Thus, it can be concluded that CKA is a genetically-defined rather than epigenetically-defined trait.

    [0501] Similar results were obtained for SCDNs of donors LC252, LC253 and LC254 (FIG. 10).

    Example 19

    [0502] Demonstrating that CKA of Neutrophils is Genetically Encoded

    [0503] Neutrophils isolated from three different donors (DDNs), as well as SCDNs derived from CD34+ stem cells of the same donors were tested for CKA.

    [0504] FIG. 11 shows the maximum percentage cytotoxicity recorded by the CKA assay (xCELLigence assay—carried out for up to 50 hours) against HeLa cells for donors LC252, LC253 and LC254 for the DDNs and SCDNs. Surprisingly, the SCDNs demonstrated a CKA which was highly similar to that of the DDNs from the same donor, again demonstrating that CKA is encoded at the genetic level. Similarly to FIG. 10, donor LC253 provided neutrophils (and SCDNs) with the highest CKA, while donors LC252 and LC254 provided neutrophils (and SCDNs) having lower CKA.

    [0505] This demonstrates that donors found to have neutrophils (e.g. DDNs) with a high CKA may also be used as a source of CD34+ stem cells which can be differentiated into neutrophils (e.g. SCDNs) with similarly high CKA.

    [0506] Similar results were obtained for SCDNs of donors LC267, LC268 and LC269 (FIG. 12—carried out for up to 45 hours).

    Example 20

    [0507] Demonstrating that SCDNs Kill Cancer Cells More Rapidly than DDNs

    [0508] The CKA of SCDNs and DDNs of donors LC267, LC268, and LC269 was determined up to a period of 45 hours. The assay was carried out according to Example 11.

    [0509] Surprisingly, the results (FIG. 13) show that SCDNs kill cancer cells more rapidly than DDNs from the same donor. The SCDNs of donor LC269 showed particularly rapid cancer killing efficacy, killing ˜50% of cancer cells in ˜18 hours (compared with 35% for DDNs), with half-maximal kill for SCDNs occurring within 10 hours (compared with negligible killing at this time for DDNs).

    Example 21

    Isolation of High-Density Neutrophils

    [0510] 10 ml of heparinized (20 U/ml) human blood is mixed with an equal volume of 3% Dextran T500 in saline and incubated for 30 minutes at room temperature to sediment erythrocytes. A 50 ml conical polypropylene tube is prepared with 10 ml sucrose 1.077 g/ml and slowly layered with a leukocyte-rich supernatant on top of the 1.077 g/ml sucrose layer prior to centrifuging at 400×g for 30 minutes at room temperature without brake. The high-density neutrophils (HDN) appear in the pellet. Low-density neutrophils (LDN) co-purify with monocytes and lymphocytes at the interface between the 1.077 g/ml sucrose layer and plasma.

    [0511] The HDNs may be tested in a CKA assay described herein. Haematopoietic cells are suitably obtained from a donor having HDNs.

    Example 22

    [0512] Differentiation of Induced Pluripotent Stem Cells (iPSCs) into Neutrophils with High CKA

    [0513] A donor comprising neutrophils with high CKA is identified. A somatic cell (e.g. fibroblast) is isolated from the donor and used to establish a culture of iPSCs. The iPSCs are differentiated into mature neutrophils, e.g. using the protocol as described by Sweeney C L, Merling R K, Choi U, Priel D B, Kuhns D B, Wang H and Malech H L, Generation of functionally mature neutrophils from induced pluripotent stem cells. Neutrophil Methods and Protocols, Methods in Molecular Biology. 2014; 1124:189-206, and Sweeney et al (2016), Stem Cells, 34(6), 1513-1526 (the teaching of which is incorporated herein by reference).

    [0514] The resulting mature neutrophils are shown to have similar CKA levels to those of the DDNs and SCDNs from HSCs (as tested by both the MTT and xCELLigence assay) from the same donor.

    [0515] The mature neutrophils are subsequently injected into the donor from which the iPSCs have been originally derived, and do not provoke any immune response.

    [0516] All publications mentioned in the above specification are herein incorporated by reference. Various modifications and variations of the described methods and system of the present invention will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. Although the present invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in biochemistry and biotechnology or related fields are intended to be within the scope of the following claims.

    CLAUSES

    [0517] 1. An in vitro cell culture of haematopoietic cells, wherein said haematopoietic cells differentiate to form granulocytes characterised by: [0518] a. a surface potential defined by an electrophoretic mobility of at least 1.0 μm.Math.cm/volt.Math.sec; and [0519] b. the ability to kill cancer cells. [0520] 2. An in vitro cell culture of haematopoietic cells, wherein said haematopoietic cells differentiate to form granulocytes characterised by: [0521] a. a density of at least 1.077 g/ml; and [0522] b. the ability to kill cancer cells. [0523] 3. An in vitro cell culture of haematopoietic cells, wherein said haematopoietic cells differentiate to form granulocytes characterised by: [0524] a. expression or activity of toll-like receptors; and/or an absence of expression or inactivity of: programmed death 1 (PD-1) receptor; CD115; CD224; CXCR1; and/or CXCR2; and [0525] b. the ability to kill cancer cells. [0526] 4. An in vitro cell culture according to clause 1, wherein the haematopoietic cells differentiate to form granulocytes further characterised by: [0527] a. a density of at least 1.077 g/ml; and/or [0528] b. expression or activity of toll-like receptors; and/or an absence of expression or inactivity of: programmed death 1 (PD-1) receptor; CD115; CD224; CXCR1; and/or CXCR2. [0529] 5. An in vitro cell culture according to clause 3 or 4, wherein the granulocytes are characterised by expression or activity of toll-like receptors; and an absence of expression or inactivity of: programmed death 1 (PD-1) receptor; CD115; CD224; CXCR1; and CXCR2. [0530] 6. An in vitro cell culture according to any one of the preceding clauses, wherein the cell culture is enriched for the haematopoietic cells. [0531] 7. An in vitro cell culture according to any one of the preceding clauses, wherein at least 70% of the cells in the in vitro cell culture are the haematopoietic cells. [0532] 8. An in vitro cell culture according to any one of the preceding clauses, wherein the haematopoietic cells are obtainable from a donor, preferably a human donor. [0533] 9. An in vitro cell culture according to clause 8, wherein the donor is a male donor. [0534] 10. An in vitro cell culture according to clause 8 or 9, wherein the donor is aged 18 to 25. [0535] 11. An in vitro cell culture according to any one of the preceding clauses, wherein the haematopoietic cells have a greater surface potential than otherwise identical haematopoietic cells that differentiate to form granulocytes having a surface potential defined by an electrophoretic mobility of less than 1.0 μm.Math.cm/volt.Math.sec and/or a reduced ability to kill cancer cells, when compared to feature b defined in clause 1, 2, or 3. [0536] 12. An in vitro cell culture according to any one of the preceding clauses, wherein the haematopoietic cells have a surface potential defined by an electrophoretic mobility of at least 1.0 μm.Math.cm/volt.Math.sec or at least 2.0 μm.Math.cm/volt.Math.sec or at least 2.5 μm.Math.cm/volt.Math.sec or at least 3.0 μm.Math.cm/volt.Math.sec. [0537] 13. An in vitro cell culture according to any one of the preceding clauses, wherein the granulocytes have a surface potential defined by an electrophoretic mobility of at least 2.0 μm.Math.cm/volt.Math.sec or at least 2.5 μm.Math.cm/volt.Math.sec or at least 3.0 μm.Math.cm/volt.Math.sec. [0538] 14. An in vitro cell culture according to any one of the preceding clauses, wherein the granulocyte is a neutrophil. [0539] 15. A method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: [0540] a. measuring a surface potential of a granulocyte cell obtainable from a donor; and [0541] b. selecting a haematopoietic cell from said donor when the measured surface potential is defined by an electrophoretic mobility of at least 1.0 μm.Math.cm/volt.Math.sec. [0542] 16. A method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: [0543] a. measuring the density of a granulocyte cell obtainable from a donor; and [0544] b. selecting a haematopoietic cell from said donor when the measured density of the granulocyte is at least 1.077 g/ml. [0545] 17. A method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: [0546] a. detecting the expression or activity of toll-like receptors; programmed death 1 (PD-1) receptor; CD115; CD224; CXCR1; and/or CXCR2 on a granulocyte cell obtainable from a donor; and [0547] b. selecting a haematopoietic cell from said donor when the toll-like receptors are expressed or active; and/or programmed death 1 (PD-1) receptor; CD115; CD224; CXCR1; and/or CXCR2 are not expressed or are inactive. [0548] 18. A method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: [0549] a. measuring a surface potential of the haematopoietic cell; and [0550] b. selecting a haematopoietic cell that has a greater surface potential than an otherwise identical haematopoietic cell that differentiates to form a granulocyte having a surface potential defined by an electrophoretic mobility of less than 1.0 μm.Math.cm/volt.Math.sec and/or has a reduced ability to kill cancer cells. [0551] 19. A method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: [0552] a. measuring the density of a haematopoietic cell; and [0553] b. selecting a haematopoietic cell that has a density greater than an otherwise identical haematopoietic cell that differentiates to form a granulocyte having a density of less than 1.077 g/ml and/or has a reduced ability to kill cancer cells [0554] 20. A method according to any one of clauses 15-19, wherein the haematopoietic cell has a surface potential defined by an electrophoretic mobility of at least 1.0 μm.Math.cm/volt.Math.sec. [0555] 21. A method according to any one of clauses 15-20, wherein the haematopoietic cell has a surface potential defined by an electrophoretic mobility of at least 2.0 μm.Math.cm/volt.Math.sec or at least 2.5 μm.Math.cm/volt.Math.sec or at least 3.0 μm.Math.cm/volt.Math.sec. [0556] 22. A method according any one of clauses 15-21, wherein the surface potential is determined by electrophoresis. [0557] 23. A method according to any one of clauses 15-22 further comprising discarding haematopoietic cells that are not selected in step b. of any one of clauses 15-19. [0558] 24. A method according to any one of clauses 15-23, wherein the haematopoietic cell is a haematopoietic stem cell. [0559] 25. A method according to any one of clauses 15-24, wherein the haematopoietic cell is a granulocyte precursor cell, such as a common myeloid progenitor cell, a myeloblast, a N. promyelocyte, a N. myelocyte, a N. metamyelocyte, a N. band, or combinations thereof. [0560] 26. A method according to any one of the clauses 15-25, wherein the granulocyte is a neutrophil. [0561] 27. A method according to any one of clauses 15-26 further comprising differentiating the haematopoietic cell into a granulocyte. [0562] 28. A method according to any one of clauses 16-27, wherein the haematopoietic cell is obtainable from a donor, preferably a human donor. [0563] 29. A method according to any one of clauses 15-28, wherein the donor is a male donor. [0564] 30. A method according to any one of clauses 15-29, wherein the donor is aged 18 to 25. [0565] 31. An in vitro method for selecting a haematopoietic cell suitable for use in treating cancer, said method comprising: [0566] a. admixing a granulocyte obtainable from a donor with a cell line to form an admixture; [0567] b. incubating said admixture; [0568] c. measuring the % of cancer cells killed in said admixture; and [0569] d. selecting a haematopoietic cell from said donor when said granulocyte kills at least 70% of the cancer cells in the admixture. [0570] 32. Use of a surface potential of a haematopoietic cell, for selecting a cell that can be differentiated into a granulocyte that is suitable for treating cancer, wherein the surface potential is greater than the surface potential of an otherwise identical haematopoietic cell that differentiates to form a granulocyte having a surface potential defined by an electrophoretic mobility of less than 1.0 μm.Math.cm/volt.Math.sec and/or has a reduced ability to kill cancer cells. [0571] 33. Use according to clause 32, wherein the haematopoietic cell has a surface potential defined by an electrophoretic mobility of at least 1.0 μm.Math.cm/volt.Math.sec, or at least 2.0 μm.Math.cm/volt.Math.sec, or at least 2.5 μm.Math.cm/volt.Math.sec, or at least 3.0 μm.Math.cm/volt.Math.sec. [0572] 34. An in vitro method for selecting a granulocyte suitable for use in treating pancreatic cancer, said method comprising: [0573] a. admixing a granulocyte with a pancreatic cancer cell line to form an admixture; [0574] b. incubating said admixture; [0575] c. measuring the % of pancreatic cancer cells killed in said admixture; and [0576] d. selecting a granulocyte that kills at least 70% of the pancreatic cancer cells in the admixture. [0577] 35. An in vitro method according to clause 34, wherein the pancreatic cancer cell line is a pancreatic ductal adenocarcinoma cell line. [0578] 36. An in vitro method for selecting a granulocyte suitable for use in treating cancer, said method comprising: [0579] a. admixing a granulocyte with a plurality of different cancer cell lines to provide a plurality of admixtures; [0580] b. incubating said admixtures; [0581] c. measuring the % of cancer cells killed in said admixtures; and [0582] d. selecting a granulocyte as suitable for use in treating a cancer of the same type/subset as the cancer cell line, when said granulocyte kills at least 70% of the cancer cells in the admixture. [0583] 37. An in vitro method according to any one of clauses 34-36 further comprising discarding granulocytes that kill less than 70% of the cancer cells in the admixture. [0584] 38. An in vitro method according to any one of clauses 34-37, wherein the granulocyte is obtainable from a donor, preferably a human donor. [0585] 39. An in vitro method according to any one of clauses 34-38, wherein the granulocyte is obtainable from a subject having a cancer of a different type/subset to the cancer cell line(s) used in the method. [0586] 40. An in vitro method according to any one of clauses 34-39, wherein the cancer cell line(s) is one or more selected from: a pancreatic cancer cell line, a liver cancer cell line, an oesophageal cancer cell line, a stomach cancer cell line, a cervical cancer cell line, an ovarian cancer cell line, a lung cancer cell line, a bladder cancer cell line, a kidney cancer cell line, a brain cancer cell line, a prostate cancer cell line, a myeloma cancer cell line, a non-Hodgkin's lymphoma (NHL) cell line, a larynx cancer cell line, a uterine cancer cell line, or a breast cancer cell line. [0587] 41. An in vitro method according to any one of clauses 38-40, further comprising obtaining a haematopoietic cell from the donor from whom the selected granulocyte is obtainable. [0588] 42. A granulocyte obtainable by a method according to any one of clauses 34-41. [0589] 43. A method comprising differentiating an in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or haematopoietic cells obtainable according to a method of any one of clauses 15-31 into granulocytes. [0590] 44. An in vitro cell culture of granulocytes obtainable by a method of clause 43, wherein said cell culture is enriched with granulocytes having: [0591] a. a surface potential defined by an electrophoretic mobility of at least 1.0 μm.Math.cm/volt.Math.sec; and [0592] b. the ability to kill cancer cells. [0593] 45. An in vitro cell culture of granulocytes obtainable by a method of clause 43, wherein said cell culture is enriched with granulocytes having: [0594] a. a density of at least 1.077 g/ml; and [0595] b. the ability to kill cancer cells. [0596] 46. An in vitro cell culture of granulocytes obtainable by a method of clause 43, wherein said cell culture is enriched with granulocytes having: [0597] a. expression or activity of toll-like receptors; and/or an absence of expression or inactivity of: programmed death 1 (PD-1) receptor; CD115; CD224; CXCR1; and/or CXCR2; and [0598] b. the ability to kill cancer cells. [0599] 47. A pharmaceutical composition comprising: [0600] a. a haematopoietic cell or a granulocyte; and [0601] b. a granulocyte-macrophage colony-stimulating factor (GM-CSF), a granulocyte colony-stimulating factor (G-CSF), a growth hormone; serotonin, vitamin C, vitamin D, glutamine (Gln), arachidonic acid, AGE-albumin, an interleukin, TNF-alpha, Flt-3 ligand, thrombopoietin, foetal bovine serum (FBS), or combinations thereof. [0602] 48. An in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to clauses 44-46, or a pharmaceutical composition according to clause 47, for use in treating cancer. [0603] 49. Use of an in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47, in the manufacture of a medicament for treating cancer. [0604] 50. A method for treating cancer comprising: administering to a subject in need thereof an in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47. [0605] 51. An in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47 for use, use or method according to any one of clauses 48-50, wherein the cancer is a solid tumour cancer. [0606] 52. An in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47 for use, use or method according to any one of clauses 48-50, wherein the cancer is one or more of: pancreatic cancer, liver cancer, oesophageal cancer, stomach cancer, cervical cancer, ovarian cancer, lung cancer, bladder cancer, kidney cancer, brain cancer, prostate cancer, myeloma cancer, non-Hodgkin's lymphoma (NHL), larynx cancer, uterine cancer, or breast cancer. [0607] 53. An in vitro method for selecting a subject for treatment with an in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47, said method comprising: [0608] a. admixing a granulocyte from said subject with a cancer cell line; [0609] b. incubating said admixture; [0610] c. measuring the % of cancer cells killed in said admixture; and [0611] d. selecting a subject for treatment with an in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47, when the granulocyte from said subject kills less than 70% of the cancer cells in the admixture. [0612] 54. An in vitro method according to clause 53, wherein the subject is selected for treatment if the granulocyte from said subject kills less than 50% or less than 25% (preferably less than 10% or 5%) of the cancer cells in the admixture. [0613] 55. A cell bank comprising an in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47. [0614] 56. A kit comprising: [0615] a. in vitro cell culture of haematopoietic cells according to any one of clauses 1-14, or a granulocyte according to clause 42, or an in vitro cell culture of granulocytes according to any one of clauses 44-46, or a pharmaceutical composition according to clause 47; and [0616] b. instructions for use of same in medicine. [0617] 57. A kit according to clause 56, wherein said instructions are for use of same in treating cancer, preferably pancreatic cancer.