PDCD1LG2 and neoplasm: In addition, CAFs have been shown to impact the cytolytic activity of CD8+ T cells through different mechanisms, such as the production of prostaglandin E2 and nitric oxide to dampen CD8+ T cell proliferation, expression of PD-L2 and FasL to promote CD8+ T cell apoptosis, and induction of abnormal ECM deposition and remodeling to physically trap CD8+ T cells and prevent effective tumor access (41).