Anti-epiregulin antibodies are used in the immunodetection of the protein encoded by the EREG gene. In humans, the canonical protein has a reported length of 169 amino acid residues and a mass of 19 kDa. Its subcellular localization is in the cell membrane. The epiregulin protein is involved with the morphogenesis of anatomical structure and angiogenesis, among other functions. Post-translational modifications have been described, including glycosylation. Other names for this target antigen include EPR and ER.