Clone REA166 recognizes the human glycoprotein A repetitions predominant (GARP) antigen, a 80 kDa type I membrane glycoprotein which belongs to the family of leucine rich repeat proteins. Expression of GARP protein is found on megakaryocytes, platelets, and activated regulatory T cells (Treg cells). GARP has been found to be associated with latency associated peptide (LAP), the prodomain responsible for conferring latency to non-active TGF-β. Thus, GARP as a latent TGF-β–binding protein (LTBP) regulates the surface expression of TGF-β and serves as a carrier of LAP, at the cell surface, to immune response active sites, where TGF-β is eventually activated and released to exert further physiological functions such as differentiation of regulatory T cells. 

Additional information: Clone REA166 displays negligible binding to Fc receptors.