Recombinant Human CD28 Protein

CD28 (Cluster of Differentiation 28) is one of the proteins expressed on T cells that provide co-stimulatory signals required for T cell activation and survival. T cell stimulation through CD28 in addition to the T-cell receptor (TCR) can provide a potent signal for the production of various interleukins (IL-6 in particular). CD28 is the receptor for CD80 (B7.1) and CD86 (B7.2) proteins. CD28 is the only B7 receptor constitutively expressed on naive T cells. CD28 was also identified on bone marrow stromal cells, plasma cells, neutrophils and eosinophils. As a homodimer of two chains with Ig domains binds B7 molecules on APCs and it can promotes T cells proliferation and differentiation, stimulates production of growth factors and induces the expression of anti-apoptotic proteins.