Anti-HPR antibodies are used in the immunodetection of the protein haptoglobin-related protein. In humans, the canonical protein has a reported length of 348 amino acid residues and a mass of 39 kDa. It has been described to be a secreted protein. Up to 2 different isoforms have been reported for this protein. It is notably expressed in the liver. It is a member of the Peptidase S1 protein family. Synonyms for this target antigen include HP, Haptoglobin-related locus, and A-259H10.2. A number of HPR antibodies have been mentioned in research publications and have associated citations. Western Blot is a widely used application for these antibodies. In addition, Immunohistochemistry is also a common application.