Successful Generation of iPSC-Derived CD4+ and CD8+ CAR T Cells with Αβ-like T Cell Function, Including Antigen-Dependent Expansion and IL-2 Production

Off-the-shelf CAR-T cell therapies promise to build on the efficacy of their autologous counterparts while providing patients with a well-defined, scalable, and cost-effective drug product that can be administered on-demand. Their successful development requires complex engineering to prevent graft vs host disease (GvHD) and rejection by the patient's immune system in addition to providing the cells with anti-tumor capabilities, such as tumor targeting. Induced pluripotent stem cells (iPSCs) can self-renew and have the potential to make any cell in the adult body. For this reason, the iPSC platform offers the opportunity to precisely engineer cells with desired characteristics that can be expanded, characterized, and banked for future differentiation to any desired cell type. To date, a major challenge for the application of this approach for making CAR T cell therapies has been the lack of a robust, scalable method to generate CAR T cells that function like healthy donor ab T cells. We report the first demonstration of an iPSC-derived CAR T cell that has αβ-like T cell function. iPSCs were engineered with a BCMA or CD19 CAR and differentiated using a novel, feeder-free method designed to mimic normal human T cell development. By successfully generating a pure CD4+/CD8+ double positive T cell population through controlled delivery of Notch ligands and other important developmental cues, we enabled the subsequent induction of both CD4+ and CD8+ T cells that have αβ-like properties. At the end of this process, a mix of CD4+ and CD8+ iPSC CAR T cells displayed Ag-dependent cytotoxicity, proliferation, and cytokine production, including IL-2 that was comparable to primary CAR T cell levels. Importantly, these attributes resulted in robust and prolonged control of tumor cells in vitro without the need for exogenous cytokines as well as tumor control in standard in vivo tumor models. These data provide support for the use of this platform for the development of allogeneic CAR T cell medicines.