Abstract 488: Establishing consistent methods for the generation of donor-derived iPSCs from T cell subsets

Abstract

T cell-based immunotherapies offer a potent and specific solution to grievous diseases such as cancer and viral infections. Expansion and re-infusion of antigen specific T cells has seen success in the treatment of metastatic melanoma and prevention of viral infections such as CMV and EBV. Additionally, engineered T cell therapies, especially chimeric antigen receptor (CAR) T cells, have been met with great clinical success and spurred innovation within the field of cellular immunotherapies. While promising, these therapies rely on sourcing T cells from donor derived blood. This process is invasive to the patient, especially when multiple or prolonged blood draws are required to obtain sufficient T cell numbers. Additionally, T cells sourced from diseased patients are often exhausted and display significantly perturbed growth and dysfunctional responses to antigen stimulation. An appealing alternative is somatic reprogramming of T cells to generate induced pluripotent stem cells (iPSCs) and differentiated into rejuvenated T cells that retain the original TCR, particularly with tumor infiltrating lymphocytes or viral specific T cells. We had previously reported a Sendai-virus based CytoTune 2.1 Reprogramming specifically designed for translational and clinical research. In this study we examine the effect of various cellular phenotypes and optimize methods for consistent reprogramming of multiple donor T cell reprogramming. Additionally, pan CD3+ cells isolated using different methods and further enriched for CD4+ and CD8+ were successfully reprogrammed. The resulting iPSCs were extensively characterized to ensure that pluripotency was achieved and that TCR sequences were preserved. This approach of reprogramming T cells and specific cell subtypes to derive iPSC with a known TCR sequence enables their use for downstream application as a renewable source of T cells with known antigen specificity. Citation Format: Mark Landon, Chad C. MacArthur, Melissa E. Hernandez, Uma Lakshmipathy, Jerry Guzman. Establishing consistent methods for the generation of donor-derived iPSCs from T cell subsets [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 488.