[Development of "Off the Shelf" T Cells for Cancer Immunotherapy]

In the area of cancer immunotherapy, the efficacy of strategies in which patient derived T cells are genetically modified ex vivo and administered to patients has been demonstrated. However, some issues have remained to be addressed; the method using autologous T cells is costly and time consuming, and their quality is unstable. The time consuming problem can be solved by preparing allogeneic T cells in advance. Peripheral blood is being considered as a source of allogeneic T cells, and methods are being explored to avoid the risk of rejection or GVHD, but even so the issues of cost and quality stability still remain. On the other hand, use of pluripotent stem cells such as iPS cells or ES cells as material of T cells may solve the cost issue and achieve homogeneity of products. The authors group has been developing a method to generate T cells from iPS cells transduced with a certain T cell receptor gene, and is currently preparing for clinical trials. We believe that, when this strategy is realized, it becomes possible to deliver a universal and homogeneous T cell preparation immediately when needed.