ENTPD1 and neoplasm: By day 21, the majority (89.7%) of the intrahepatic TILs expressed CD39 (Figure 2A).28–30 Notably, both livers from subcutaneous tumor-bearing mice and spleens from intrahepatic tumor-bearing mice showed an increase in the frequency of CD39+ TAS CD8+ T cells on day 21 (Figure 2A).