Senescent CD8+ T cell

Senescent CD8+ T cells are a subtype of cytotoxic T lymphocytes that have undergone extensive replicative cycles or chronic antigenic stimulation (e.g., due to aging, chronic infections, autoimmunity, or cancer) and have entered a state of reduced proliferative capacity, altered effector function, and typically increased secretion of pro-inflammatory cytokines. These cells often lose expression of costimulatory molecules such as CD28, display markers including CD57 and KLRG1, and accumulate with age or chronic disease. Their presence is associated with a decline in adaptive immunity, greater risk of morbidity from infections, impaired vaccine response, and contribution to chronic inflammatory ("inflammaging") and age-related diseases. They are not a single protein or receptor target, but rather a cell population with complex biological and disease implications.

Other names

Senescent CD8+ T lymphocyteCD8+ T cell immunosenescenceCD8+CD28− T cell (a commonly used surrogate for senescent phenotype)

Not directly applicable; however, therapies may aim to: - Reduce or reverse senescence in T cells - Eliminate senescent T cells (via immune modulation or senolytic agents) - Restore costimulatory signaling (e.g., targeting CD28 pathway)