Fig. 5. CAR8 failure in an OT1 TCR transgenic T cell after exposure to OVA. CAR8 failure in an OT1 TCR transgenic T cell after exposure to OVA. (A) CD107a expression on OT1-CAR T cells generated from Rag1−/− OT1 spleens at 4 hours of coincubation with E2aPbx expressing CD19 and/or OVA antigens. Iso cntrl, isotype control. (B) Percent viable E2aPbx cells expressing varying combinations of the CD19 and OVA antigens after 3 days of coculture with OT1-CAR or mock-OT1 T cells. (C) OVA-expressing hematopoietic chimeras were generated by CD3-depleted bone marrow transplant 21 days before inoculation with 1 × 106 E2aPbx, with lymphodepletion and 1 × 106 CD19 OT1-CAR8 cell treatment on day 0. (D) Survival of OVA chimeric mice treated with OT1-CAR8 T cells. (E) Leukemia burden of OT1-CAR8–treated mice 7 days after infusion. BM, bone marrow. (F and G) Analysis of infused OT1-CAR8 cells from the bone marrow 7 days after infusion. (F) PD-1 expression and (G) LAG3 expression on OT1-CAR8 cell [for (E) to (G): *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, relative to the WT→WT group, one-way ANOVA performed for all comparisons and log-rank Mantel-Cox test for survival analysis]. Yinmeng Yang et al., Sci Transl Med 2017;9:eaag1209 Published by AAAS