Purified anti-mouse CD4

CD4 is a 55 kD protein, also known as L3T4 or T4. It is a member of the Ig superfamily, primarily expressed on most thymocytes, a subset of T cells, and weakly on macrophages and dendritic cells. It acts as a coreceptor with the TCR during T cell activation and thymic differentiation by binding MHC class II and associating with the protein tyrosin kinase, lck. The H129.19 antibody is able to block CD4 mediated cell adhesion and T cell activation. It is also useful for in vivo and in vitro depletion of CD4+ T cells. H129.19 antibody blocks binding of the anti-mouse CD4 mAbs GK1.5 and RM4-5, but not RM4-4 antibody. H129.19 antibody inhibits various responses of T helper cells to antigenic or mitogenic stimuli.