Regeneration of Tumor-Antigen-Specific Cytotoxic T Lymphocytes from iPSCs Transduced with Exogenous TCR Genes

Takuya Maeda,Seiji Nagano,Soki Kashima,Koji Terada,Yasutoshi Agata,Hiroshi Ichise,Manami Ohtaka,Mahito Nakanishi,Fumihiro Fujiki,Haruo Sugiyama,Toshio Kitawaki,Norimitsu Kadowaki,Akifumi Takaori-Kondo,Kyoko Masuda,Hiroshi Kawamoto

doi:10.1016/j.omtm.2020.09.011

Abstract

In the current adoptive T cell therapy, T cells from a patient are given back to that patient after ex vivo activation, expansion, or genetic manipulation. However, such strategy depends on the quality of the patient’s T cells, sometimes leading to treatment failure. It would therefore be ideal to use allogeneic T cells as “off-the-shelf” T cells. To this aim, we have been developing a strategy where potent tumor-antigen-specific cytotoxic T lymphocytes (CTLs) are regenerated from T-cell-derived induced pluripotent stem cells (T-iPSCs). However, certain issues still remain that make it difficult to establish highly potent T-iPSCs: poor reprogramming efficiency of T cells into iPSCs and high variability in the differentiation capability of each T-iPSC clone. To expand the versatility of this approach, we thought of a method to produce iPSCs equivalent to T-iPSCs, namely, iPSCs transduced with exogenous T cell receptor (TCR) genes (TCR-iPSCs). To test this idea, we first cloned TCR genes from WT1-specific CTLs regenerated from T-iPSCs and then established WT1-TCR-iPSCs. We show that the regenerated CTLs from TCR-iPSCs exerted cytotoxic activity comparable to those from T-iPSCs against WT1 peptide-loaded cell line in in vitro model. These results collectively demonstrate the feasibility of the TCR-iPSC strategy.

Highlights

Some adoptive T cell therapies have recently demonstrated remarkable efficacy; for example, T cells forced to express T cell receptor (TCR) genes[1] or chimeric antigen receptor (CAR) genes[2,3] have been shown to be effective therapeutics in certain types of cancer
Transduction of histocompatibility leukocyte antigen (HLA)-Homo induced pluripotent stem cell (iPSC) with WT1-TCR Genes and Regeneration of cytotoxic T lymphocytes (CTLs) from the TCR-iPSCs We first established iPSCs from monocytes derived from the HLAhomo donor as parental iPSCs (Figure 1A) using the Sendai virus system shown in the previous report.[11]
In the present study, we have succeeded in producing potent CTLs from iPSCs transduced with exogenous TCR genes

Summary

Introduction

Some adoptive T cell therapies have recently demonstrated remarkable efficacy; for example, T cells forced to express T cell receptor (TCR) genes[1] or chimeric antigen receptor (CAR) genes[2,3] have been shown to be effective therapeutics in certain types of cancer. Adoptive T cell therapies are essentially conducted in an autologous setting, where the peripheral T cells are collected from each patient, expanded, and transduced with, for instance, a TCR-expressing retrovirus vector, resulting in a very high cost for each treatment Another issue is that the quality of the final product depends on the initial quality of the patients’ T cells, which are not good enough in some cases.[4]. To resolve these issues, it would be preferable to conduct adoptive immune cell therapy in an allogeneic setting, where it will be possible to use “off-the-shelf” T cells,[5,6,7] considerably reducing cost and standardizing quality. To make such T cells, several points need to be addressed: (1) such cells should have unlimited expansion capacity; (2) they should not be rejected by the patient’s immune system; and, most importantly, (3) they should be “monoclonal,” because polyclonal T cells inevitably contain dangerous allo-reactive T cells at some frequency

Methods

Results

Conclusion