Alternative Names
T-cell surface glycoprotein CD4; T-cell surface antigen T4/Leu-3; CD4; Scd4
Background
CD4 is an approximately 55/xa0kDa type/xa0I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T/xa0lymphocytes. It is a standard phenotype marker for the identification of T/xa0cell populations. Mature human CD4 consists of a 371/xa0amino acid extracellular region containing four immunoglobulin-like domains, a 22/xa0aa transmembrane segment, and a 40/xa0aa cytoplasmic domain. CD4 is expressed along with CD8 on double positive T/xa0cells during their development in the thymus. CD4 binds directly to MHC class/xa0II molecules on antigen presenting cells (10). This interaction contributes to the formation of the immunological synapse which is focused around the TCR-MHC class II-antigenic peptide interaction. CD4 also functions as a chemotactic receptor for IL-16 and, in human, as a co-receptor for the gp120 surface glycoprotein of HIV-1.
Note
For Research Use Only , Not for Diagnostic Use.