Method for inducing antigen specific CD8 positive T cells

1. A method for inducing CD4 − CD8 + T cells in vitro, comprising the steps of:

(1) differentiating pluripotent stem cells to give a cell culture comprising CD4 − CD8 − T cells and CD4 + CD8 + T cells,

(2) removing CD4 − CD8 − cells and CD4 − CD8 + cells from the cell culture obtained in step (1) to obtain a CD4 + CD8 + enriched cell culture, wherein 5% or less of the cells are CD4 − CD8 − cells,

(3) differentiating the CD4+CD8+cells in the cell culture into CD4 − CD8+T cells, wherein the CD8 antigen of the CD4 − CD8 + T cells is a heterodimer composed of CD8α and CD8β chains.

2. The method according to claim 1 , wherein the pluripotent stem cells are iPS cells.

3. The method according to claim 2 , wherein the pluripotent stem cells are iPS cells homozygous for HLA haplotype.

4. The method according to claim 1 , wherein the pluripotent stem cells bear rearranged genes encoding a T cell receptor or a chimeric antigen receptor specific for a desired antigen and CD4 − CD8 + T cells having a cytotoxic activity specific for the antigen are induced.

5. The method according to claim 4 , wherein the pluripotent stem cells bear rearranged genes encoding a T cell receptor specific for the desired antigen.

6. The method according to claim 5 , wherein the pluripotent stem cells are T-iPS cells induced from human T cells bearing rearranged genes encoding a T cell receptor specific for the desired antigen.

7. The method according to claim 5 , wherein the pluripotent stem cells are TCR-iPS cells obtained by introducing rearranged genes encoding a T cell receptor specific for the desired antigen into human T cells.

8. The method according to claim 4 , wherein the step of differentiating CD4 + CD8 + cells into CD4 − CD8 + T cells is performed by directly activating any one of the activation pathways which occur upon stimulation of the T cell receptor.

9. The method according to claim 8 , wherein the step of differentiating CD4 + CD8 + cells into CD4 − CD8 + T cells is performed by using anti-CD3 antibody.

10. The method according to claim 8 , wherein the step of differentiating CD4 + CD8 + cells into CD4 − CD8 + T cells is performed by stimulating the cells with the desired antigen.

11. The method according to claim 10 , wherein the step of differentiating CD4 + CD8 + cells into CD4 − CD8 + T cells is performed by stimulating the cells with antigen presenting cells that present the desired antigen.

12. The method according to claim 1 , for establishment of CD4 − CD8 + T cells having a cytotoxic activity specific for the antigen, further comprising the step of introducing a T cell receptor or a chimeric antigen receptor specific for the desired antigen into the induced CD4 − CD8 + T cells.

13. The method according to claim 12 , for introducing a T cell receptor specific for the desired antigen into the induced CD4 − CD8 + T cells.

14. The method according to claim 4 , further comprising the step of further proliferating the obtained CD4 − CD8 + T cells specific for the desired antigen.

15. The method according to 20, wherein the step of further proliferating the obtained CD4 − CD8 + T cells is performed by directly activating any part of the activation pathway which occurs on stimulating a T cell receptor.

16. The method according to claim 14 , wherein the step of further proliferating the obtained CD4 − CD8 + T cells is performed by using anti-CD3 antibody.

17. The method according to claim 14 , wherein the step of further proliferating the obtained CD4 − CD8 + T cells is performed by stimulating the cells with the desired antigen.

18. The method according to claim 17 , wherein the step of further proliferating the obtained CD4 − CD8 + T cells is performed by stimulating the cells with antigen presenting cells that present the desired antigen.