PRF1 and renal cell carcinoma: Notably, LAMP1 and perforin were identified as the most representative cytotoxic molecules of RCC-infiltrating CD3low Vγ9 δ1 T cells, whereas peripheral circulating CD3high Vγ9 δ2 T cells only expressed high levels of granzyme A. Granzyme A is the first to become detectable during differentiation into memory cells, followed by granzyme B and later perforin [13], supporting our findings that most RCC-infiltrating CD3low Vγ9 δ1 T cells and peripheral circulating CD3high were TEM and TCM, respectively.