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

Description :
CD80, also known as the B-cell activation antigen B7-1, is a single-pass type I transmembrane 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. Human CD80 also interacts with human and mouse PD-L1/B7-H1.