Multiple T-lymphocyte and immune cell surface proteins

Multiple T-lymphocyte and immune cell surface proteins refers to a broad and heterogeneous group of molecules, primarily glycoproteins, expressed on the surface of T-cells and other immune cells that mediate critical biological processes such as antigen recognition, signal transduction, and cell-to-cell communication (NIH, 2023). These proteins are often categorized using the Cluster of Differentiation (CD) nomenclature, which includes well-known therapeutic targets like CD3, CD4, CD8, PD-1, and CTLA-4 (UniProt, 2024). In clinical practice, these proteins are targeted by a variety of monoclonal antibodies and fusion proteins to treat conditions ranging from hematologic malignancies and solid tumors to autoimmune diseases and organ transplant rejection (PubMed, 2022). For example, checkpoint inhibitors like pembrolizumab target the PD-1 receptor to enhance the body's anti-tumor immune response, while drugs like abatacept modulate T-cell costimulation to treat rheumatoid arthritis (StatPearls, 2023). Because this term encompasses hundreds of distinct proteins with widely varying functions and therapeutic implications, it is considered a functional category rather than a single, specific therapeutic target. Consequently, drug development and clinical diagnostics focus on individual proteins within this group rather than the group as a whole (Nature Reviews Immunology, 2021).

Other names

Immune cell surface markersT-cell surface antigensCluster of differentiation antigensCD markersLeukocyte surface proteins

Modulation of immune cell activity through agonism or antagonism of specific surface receptors to either enhance or suppress immune responses.