Lymphoma-derived extracellular vesicles inhibit CAR T cell function

CD19-targeting CAR T cell therapy has shown remarkable efficacy in the treatment of relapsed/refractory B cell lymphoma. However, a proportion of patients exhibit resistance to treatment. We investigate the impact of lymphoma-derived Extracellular Vesicles (EV) on CD19-targeting CAR T cell function in vitro . We demonstrate that lymphoma-EV express B cell markers such as CD19 and CD20, which can be transferred to the CAR T cell membrane. In co-culture experiments, lymphoma-EV suppress the tumour-killing capacity of CAR T cells.