Anti-carbonic anhydrase 2 antibodies are used in the immunodetection of the protein encoded by the CA2 gene. In humans, the canonical protein has a reported length of 260 amino acid residues and a mass of 29.2 kDa. Its subcellular localization is in the cell membrane and cytoplasm. A member of the Alpha-carbonic anhydrase protein family, it is known to catalyze the reversible hydration of carbon dioxide. Other names for this target antigen include CA-II and CAC.