[Term] id: PR:000001004 name: CD4 molecule def: "A protein that is a translation product of the human CD4 gene or a 1:1 ortholog thereof. CD4 is an accessory protein for MHC class-II antigen/T-cell receptor interaction. It is the primary receptor for HIV-1. CD4 has four immunoglobulin-like domains in its extracellular region that share the same structure, but can differ in sequence." [PMID:15326605] comment: Category=gene. Requested by=CL. synonym: "CD4" EXACT PRO-short-label [PRO:DNx] synonym: "T-cell surface antigen T4/Leu-3" EXACT [] synonym: "T-cell surface glycoprotein CD4" EXACT [] synonym: "T-cell differentiation antigen L3T4" EXACT [] xref: PIRSF:PIRSF001977 is_a: PR:000000001 ! protein