Early mortality results from acute GVHD. (A) Representative flow cytometry plots of CD19 and B220 representing pre–B-ALL on day 16 in peripheral blood (PB) of recipients of experiments described in Figure 1. (B) Hematoxylin and eosin stain of liver from recipients on day 7 post-BMT: allogeneic C3h.sw recipients of B6 BMT + CAR T cells (right) and syngeneic B6 recipients (left). (C-D) BM, liver, lymph nodes, and spleens were harvested in post-BMT recipients, and counted and analyzed for adoptively transferred cells using CD45 isotypes. (C) Representative flow cytometry plots for BM, lymph nodes, spleen, and liver gated on T cells. (D) Enumeration of splenocytes on day 7 post-BMT: total splenocytes, with white boxes indicating recipient or donor marrow-derived cells, and black boxes representing adoptively transferred cells, based on CD45 isoform expression (left). CAR⁺ T cells in spleens on day +7 (right). *P < .05; ***P < .001. NS, nonsignificant.