METHODS OF T CELL PRODUCTION

1 . A method of producing a population of progenitor T cells comprising;

differentiating a population of haematopoietic progenitor cells (HPCs) into progenitor T cells in the presence of a pyrimidoindole compound.

2 . A method according to claim 1 wherein the presence of the pyrimidoindole compound increases the proportion of HPCs that differentiate into progenitor T cells.

3 . A method according to any one of the preceding claims wherein the HPCs are differentiated by a method comprising culturing the population of HPCs in a lymphoid expansion medium supplemented with an effective amount of the pyrimidoindole compound.

4 . A method according to claim 3 wherein the lymphoid expansion medium consists of a chemically defined nutrient medium supplemented with effective amounts of SCF, FLT3L, TPO, IL7 and the pyrimidoindole compound.

5 . A method according to any one of the preceding claims wherein the HPCs have a CD34+ phenotype.

6 . A method according to any one of the preceding claims wherein the HPCs are differentiated by a method comprising differentiating the HPCs into common lymphoid progenitor cells (CLPs) and differentiating the CLPs into progenitor T cells.

7 . A method according to any one of the preceding claims wherein the population of HPCs is produced in vitro from induced pluripotent stem cells (iPSCs).

8 . A method according to claim 7 wherein the method comprises providing a population of iPSCs and differentiating the iPSCs into a population of HPCs.

9 . A method according to any one of the preceding claims wherein the progenitor T cells have a CD5+, CD7+ phenotype.

10 . A method for expanding progenitor T cells comprising;

culturing the progenitor T cells in the presence of a pyrimidoindole compound.

11 . A method according to claim 10 wherein the presence of the pyrimidoindole compound increases the proliferation of the progenitor T cells in the population.

12 . A method according to claim 10 or claim 11 wherein expansion of the progenitor T cells is for at least 21 days

13 . A method according to any one of the preceding claims wherein the pyrimidoindole compound is a substituted pyrimido[4,5-b]indole.

14 . A method according to claim 13 wherein the pyrimidoindole compound is methyl 4-(3-piperidin-1-ylpropylamino)-9H-pyrimido[4,5-b] indole-7-carboxylate.

15 . A method according to claim 13 wherein the pyrimidoindole compound is (1R,4R)—N1-(2-benzyl-7-(2-methyl-2H-tetrazol-5-yl)-9H-pyrimido[4,5-b]indol-4-yl)cyclohexane-1,4-diamine.

16 . A method according to any one of the preceding claims , wherein the pyrimidoindole compound is present at a concentration less than 5 μM.

17 . A method according to any one of claims 1 to 16 wherein the method further comprises introducing heterologous nucleic acid encoding an αβ TCR into the iPSCs, HPCs or progenitor T cells.

18 . A method according to claim 17 wherein the heterologous nucleic acid encoding the αβ TCR is comprised in an expression vector.

19 . A method according to claim 18 wherein the expression vector is a lentiviral vector.

20 . A method according to any one of claims 17 to 19 wherein the αβ TCR is an affinity enhanced TCR.

21 . A method according to one of claims 17 to 20 wherein the αβ TCR binds specifically to an MHC displaying a peptide fragment of a target antigen expressed by cells or specifically binds to a target antigen or peptide thereof expressed by cells independently of MHC presentation.

22 . A method according to claim 21 wherein the αβ TCR binds specifically to an MHC displaying a peptide fragment of a tumour antigen expressed by the cancer cells or binds specifically to a tumour antigen or peptide fragment thereof expressed by cancer cells independently of MHC presentation.

23 . A method according to any one of the preceding claims comprising further differentiating the progenitor T cells to produce TCR αβ+ T cells.

24 . A method according to claim 23 wherein the progenitor cells are further differentiated by a method comprising culturing the population of progenitor T cells in a T cell maturation medium.

25 . A method according to claim 23 or claim 24 wherein the TCR αβ+ T cells have a CD8+CD4+ phenotype.

26 . A method according to any one of claims 23 to 25 comprising activating and expanding the TCR αβ+ T cells to produce a population of T cells have a CD8+ single positive phenotype or a CD4+ single positive phenotype.

27 . A method according to any one of claims 23 to 26 wherein the TCR αβ+ T cells specifically bind to cells expressing a target antigen.

28 . A method according to claim 27 wherein the target antigen is a tumour antigen.

29 . A method according to claim 28 wherein the TCR αβ+ T cells specifically bind to cancer cells expressing the tumour antigen.

30 . A method according to any one of claims 23 to 29 further comprising isolating or purifying the TCR αβ+ T cells.

31 . A method according to claim 30 wherein TCR αβ+ T cells are isolated by magnetic activated cell sorting.

32 . A method according to according to any one of claims 23 to 31 further comprising concentrating the population of TCR αβ+ T cells.

33 . A method according to according to any one of claims 23 to 32 comprising storing the population of TCR αβ+ T cells.

34 . A method according to any one of claims 23 to 33 comprising formulating the population of TCR αβ+ T cells with a pharmaceutically acceptable excipient.

35 . A population of progenitor T cells produced by a method according to any one of claims 1 to 22 .

36 . A population of TCR αβ+ T cells produced by a method according to any one of claims 23 to 34 .

37 . A pharmaceutical composition comprising a population of TCR αβ+ T cells produced by a method according to any one of claims 23 to 34 and a pharmaceutically acceptable excipient.

38 . A population of TCR αβ+ T cells produced by a method according to any one of claims 23 to 34 for use in a method of treatment.

39 . A population of TCR αβ+ T cells produced by a method according to any one of claims 23 to 34 for use in a method of treatment of cancer.