CD80 molecule (CD80)

CD80 molecule (B7-1, CD80) is a type I transmembrane glycoprotein and a member of the B7 family of immune regulatory ligands, belonging to the immunoglobulin superfamily. It is expressed mainly on activated antigen-presenting cells including dendritic cells, macrophages, and B cells, where it provides a key "costimulatory" signal required for T cell activation through interaction with the CD28 and CTLA-4 (CD152) receptors on T lymphocytes. Costimulatory signals delivered by CD80 promote T cell proliferation and differentiation, while coinhibitory signals mediated by CTLA-4 dampen immune responses. CD80 also binds PD-L1, potentially reversing PD-1/PD-L1-mediated immune suppression in the tumor microenvironment. CD80 plays a significant role in immune checkpoint regulation, tolerance, and the development of autoimmune diseases, and it is an established therapeutic target in immuno-oncology and immunomodulation.

Other names

B7-1B7.1Cluster of Differentiation 80CD28 ligandCD28LGCD28LG1

Immune checkpoint modulation (either stimulating T-cells through CD28 or inhibiting via CTLA-4 interactions). Blocking PD-L1/PD-1-mediated immunosuppression (soluble CD80 binds PD-L1 to counteract PD-1 inhibition). Costimulatory signal essential for full T cell activation in the presence of antigen.