Previous reports by our group have shown M28z-mediated and MBBz-mediated trogocytosis in in vivo and in vitro models of ovarian cancer.27 45 In line with previous data, trogocytic CAR T cells displayed a TEM profile with higher expression levels of PD-1, LAG-3 and TIM-3, as well as CD56 and FASL, indicative of both activation and exhaustion.45 46 The low frequency of trogocytic M1xx CAR T cells observed in our two models suggest that superior tumor control as seen with M1xx CAR T cells correlates to lower trogocytic activity. This evidence concerns the gene FASLG and ovarian carcinoma.