Human T cell surface antigens (T-cell antigens)

Human T cell surface antigens refer to a broad and heterogeneous group of proteins, glycoproteins, and other molecules expressed on the plasma membrane of T-lymphocytes. These molecules, often classified under the Cluster of Differentiation (CD) system, serve critical roles in the immune system, including antigen recognition via the T-cell receptor (TCR) complex, co-stimulation (e.g., CD28), and cell-cell adhesion (e.g., LFA-1). They are essential for the orchestration of adaptive immune responses, allowing T cells to distinguish between self and non-self and to execute effector functions such as cytokine production or direct cytotoxicity. In clinical medicine, these antigens are primary targets for immunotherapy; for instance, monoclonal antibodies against CD3 are used for immunosuppression in organ transplantation, while checkpoint inhibitors targeting PD-1 or CTLA-4 are used to treat various malignancies. Because this term encompasses hundreds of distinct molecules with diverse functions, it is considered a category rather than a single therapeutic target.

Other names

T-lymphocyte surface markersT-cell surface glycoproteinsCluster of Differentiation (CD) antigensT-cell surface molecules

Drugs targeting these antigens typically act as agonists or antagonists to modulate T-cell signaling, induce T-cell depletion, or block inhibitory checkpoints to enhance or suppress immune responses.