Figure 4. Engrafted T cells can impact a second challenge of leukemia with change in T cell phenotype.

Mice that cleared an initial challenge of primary patient leukemia were given a second challenge of the same leukemia. A. Disease burden as measured by bioluminescent signal demonstrating delayed control of second ALL challenge by mice 321, 323, 324 with recurrence in the form of loco-regional disease. Mouse 344 successfully cleared a second challenge of leukemia without recurrence. B. Mouse 344 had effector-memory like cells in the periphery 90 days after second antigen challenge, whereas mice in the same group had T_CM after clearance of initial leukemia(Figure 4). C. Mice that developed loco-regional disease after initial clearance of their second leukemia have GFP+CD19+ leukemia within these sites of relapse without the presence of T cells, and have trace amounts of leukemia and T cells in their spleens.