ENTPD1 and neoplasm: In B16F10 tumor–bearing mice, α4-1BB in combination with Pmel A2BR–/– T cell therapy resulted in a significant increase in transferred CD8+ T cell accumulation (Figure 7, H and I) with a decreased exhausted phenotype (PD-1+TOX+ and PD-1+CD39+) (Figure 7, J and K) compared with transferred Pmel WT T cells.