CD8A and neoplasm: CD39+ CD8 T cells have previously been shown to also express elevated levels of TIM3, which is in accordance with our own observations.[35] Further, co-expression of TIM3 and CD39 was proposed as a marker of exhaustion like T cells.[18,36] Yet, CD39 was shown to identify tumor-reactive, phenotypically exhausted infiltrating CD8 T lymphocytes, still capable of cytotoxic function and recruitable by ICB.[37] Although these observations do not allow transfer to in vitro stimulated lymphocytes, we observed TIM3 to be expressed significantly higher in CD39+ CD8 T cells of OPSCC patients.