Human CD80 Protein, ECD (extracellular domain), Fc-fusion, Biotinylated, Recombinant

Description :
CD80, also known as the B-cell activation antigen B7-1, is a single-pass type I transmemebrane glycoprotein that belongs to the B7 family of the Ig superfamily. Like other B7 family members, CD80 contains 1 Ig-like C2-type domain and 1 Ig-like V-type domain in the extracellular region. Among the B7 family members, they share about 20-25% amino acid identity. CD80 is expressed on the surface of antigen-presenting cells including activated B cells, macrophages and dendritic cells. CD80 provides a co-stimulatory signal necessary for T cell activation and survival. CD80 is the ligand for two different receptors on the T cell surface: CD28 and CTLA-4 (also known as CD152). CD80 works in concert with CD86 (also known as B7-2) to prime T cells. CD80 and CD86, together with their receptors CD28 and CTLA4, constitute one of the dominant co-stimulatory pathways that regulate T and B cell responses, tolerance and the generation of CTL. The binding of CD80:CD86 to its receptor CD28 induces T-cell proliferation and cytokine production. CTLA4 binds to CD80 and CD86 with a 20-100 fold higher affinity than CD28 and is involved in the downregulation of the immune response. CD80 also binds to B7 family ligand PD-L1 to regulate immune cell activation. CD80 may act as a receptor for adenovirus subgroup B and play a role in lupus neuropathy. CD80 is regarded as a promising therapeutic target for autoimmune diseases and cancer. Human CD80 and CD86 share 26% amino acid identity, while human and mouse CD80 share 44% amino acid identity. It has been reported that both human and mouse CD80 and CD86 can bind to either human or mouse CD28 and CTLA4.