PDCD1 and acute myeloid leukemia: Finally, co-expression of PD-1 and TIM-3, indicating a T cell exhaustion phenotype, was increased on CD4+ and CD8+ T cells from NrasG12D recipients, but was only increased on the CD4+ T cells in BA/NH recipients and not increased on T cells from MA9 AML (Fig. 3F, Supplementary Fig. 5A–D).