Anti-HAPO antibodies are protein reagents that detect specific antigens. The HAPO antigen is another term for the human protein proteoglycan 4, encoded by the PRG4 gene. The protein is reported to play a role in boundary lubrication within articulating joints. Canonically, it has an amino acid length of 1404 residues and a mass of 151.1 kilodaltons. It is a secreted protein and it is reported to be highly expressed in synovial tissue, cartilage and liver and weakly in the heart and lung. Other alias names for HAPO include CACP and JCAP. Indicated applications for HAPO antibodies listed below include ELISA, Western Blot, and Immunocytochemistry.