Antigen-specific T cell (None standardized; sometimes abbreviated as "Ag-specific T cell" in the literature, but not universally.)

Antigen-specific T cells are a subset of T lymphocytes characterized by the ability to recognize and bind a particular antigenic peptide presented on major histocompatibility complex (MHC) molecules via their T cell receptor (TCR)[2][5][9]. These cells encompass various functional subtypes, including helper (CD4+), cytotoxic (CD8+), and regulatory T cells, all defined by the unique specificity of their TCR for a particular antigen. Upon activation, antigen-specific T cells undergo clonal expansion and execute effector functions, such as cytokine secretion, target cell killing, and regulation of other immune cells[1][2][5][6][7][8]. In clinical contexts, antigen-specific T cell populations are targeted or manipulated in immunotherapies for cancer, infections, autoimmunity, and transplantation. They play a central role in adaptive immunity, immune memory, and the maintenance of immune tolerance. However, "antigen-specific T cells" refers to a cell population—not a unique protein or gene—making it an imprecise molecular target designation.

Other names

Ag-specific T cellAntigen-reactive T cellEpitope-specific T cellAntigen-responsive T lymphocyte

Checkpoint inhibitors: Block inhibitory signals (e.g., PD-1/PD-L1, CTLA-4 pathways) to enhance antigen-specific T cell activity against tumors. Adoptive T cell therapy: Expand and reinfuse antigen-specific T cells to target cancers or chronic infections. Interleukin therapy: Support the survival, proliferation, or differentiation of antigen-specific T cells.