Anti-Purine Nucleoside Phosphorylase antibodies are used for the immunodetection of the protein encoded by the PNP gene. In humans, the canonical protein has a reported length of 289 amino acid residues and a mass of 32.1 kDa. Its subcellular localization is in the cytoplasm. It is reported to be expressed in red blood cells; overexpressed in red blood cells (cytoplasm) of patients with hereditary non-spherocytic hemolytic anemia of unknown etiology. A member of the PNP/MTAP phosphorylase protein family, it is known to catalyze the phosphorolytic breakdown of the N-glycosidic bond in the beta-(deoxy)ribonucleoside molecules, with the formation of the corresponding free purine bases and pentose-1-phosphate. Other names for this target antigen include PRO1837, PUNP, HEL-S-156an, epididymis secretory sperm binding protein Li 156an, inosine phosphorylase, and NP. A number of Purine Nucleoside Phosphorylase antibodies have been mentioned in research publications and have associated citations. Western Blot is a widely used application for these antibodies. In addition, ELISA is also a common application.