CD8+ cytotoxic T lymphocytes in cancer immunotherapy: A review

Tumors have specific mechanisms to break T cell responses. CD8+ T cells are the key immune cells for killing cancer cells presenting major histocompatibility complex (MHC) class I molecules. For pursuing this purpose, the cells must first be primed by their cardinal interactions with dendritic cells (DCs),  natural killer (NK) cells, and CD4+ T cells, among them play essential roles for this priming. Then, the primed cells are activated to form effector  cytotoxic T lymphocytes (CTLs) for killing cancer cells via release of granules or induction of FasL‐mediated apoptosis. In the established tumors, however, the function of these key effector cells is suppressed by immunosuppressive cross‐talking between cancer cells with tumor stromal cells l ike cancer‐associated fibroblasts (CAFs), regulatory T cells (Tregs), and macrophage type 2 (M2) cells. CTL‐based therapy can distract cancer cells, and the density of CD8+ T cells infiltrated to the invasive site of tumor is a predictive marker for influencing the outcomes of immune checkpoint blockade (ICB) blockade therapy. It is suggested to use a combination of immunotherapeutic approaches for rescuing the exhausted CTLs and switching them toward their active effector profile for retaining immunoactivation within the  tumor microenvironment (TME) for combatting tumors and enhancing the efficacy of chemo or radiotherapeutic approaches. AbstractCD8+ cytotoxic T lymphocytes (CTLs) are preferred immune cells for targeting ca...
Source: Journal of Cellular Physiology - Category: Cytology Authors: Tags: REVIEW ARTICLE Source Type: research