APC Armenian hamster Anti-Human/Mouse/Rat CD278 Antibody (S-R578)

CD278, also known as ICOS (Inducible T-cell Costimulator), is a type I transmembrane glycoprotein that belongs to the CD28 family of costimulatory immunoreceptors. It is expressed on the surface of activated T cells, including cytotoxic T cells, regulatory T cells (Tregs), and other types of T cells. Its ligand, ICOSL (B7-H2 or CD275), is found on antigen-presenting cells (APCs) such as dendritic cells and macrophages, as well as on B cells. ICOS functions as a homodimer and plays a crucial role in cell-cell signaling, immune responses, and the regulation of cell proliferation. The interaction between ICOS and ICOSL enhances T-cell activation, proliferation, and differentiation, and is essential for the development of follicular helper T cells (Tfh) and efficient B-cell antibody responses. ICOS has also been implicated in various disorders, including immunodeficiency and autoimmune diseases. In cancer immunotherapy, ICOS expression has been identified as a potential predictive biomarker for responses to checkpoint inhibitor treatments.