CD8-positive Cytotoxic T Cell Activation

CD8-positive cytotoxic T cells (CTLs) are activated upon recognition of antigenic peptides presented by MHC class I molecules on antigen-presenting cells (APCs). This activation requires both primary (TCR/MHC-I interaction) and co-stimulatory signals (e.g., CD28-CD80/86 interaction). Activated CTLs undergo clonal expansion and acquire effector functions, including direct killing of target cells via perforin/granzyme-mediated lysis or Fas/FasL-induced apoptosis, and secretion of cytokines such as IFN-gamma. Memory formation ensures long-term immunity after the initial response. CD8+ T cell activation is not a direct target, but a process that involves many targets.

Other names

Cytotoxic T Lymphocyte ActivationCTL Activation