PDCD1LG2 and neoplasm: Recently, it was reported that CAFs promote tumor immune escape by inducing antigen-mediated activation-induced cell death (AICD) of tumor-specific cytotoxic T lymphocytes (CTLs), in which CAFs process and cross-present tumor antigens and then kill CTLs in an antigen-specific, antigen-dependent manner via PD-L2 and FasL to protect tumor cells from immune destruction19.