Direct cytolysis by cytotoxic T lymphocyte activation (CTL)

Cytotoxic T lymphocyte-mediated cytolysis is the primary mechanism by which CD8+ T cells destroy virus-infected, cancerous, or otherwise abnormal cells. Upon activation, CTLs recognize antigenic peptides presented on MHC class I molecules via their T cell receptor (TCR) and receive additional co-stimulatory signals (e.g., via CD28). Activated CTLs release cytolytic granules containing perforin and granzymes, which induce target cell apoptosis. Alternatively, CTLs induce death through the Fas-Fas ligand pathway. Cytolysis is essential for immune surveillance and elimination of threats, but dysregulation can contribute to tissue damage and autoimmune disease[6][5][2][3][1][4][7].

Other names

CD8+ T cellcytotoxic T cellkiller T cell

Enhancement of CTL activity (e.g. by cytokines or checkpoint blockade); Inhibition of T cell activation (immunosuppressants)