Prostate specific antigen / PSA is a chymotrypsin-like serine protease (kallikrein family) exclusively produced by the prostate epithelium, and abundant in seminal fluid. Using a Prostate specific antigen antibody, the protein can be detected in the sera of patients with prostatic carcinoma and expression level correlates positively with the likelyhood of cancer.

Store the PSA antibody at 2-8°C (with azide) or aliquot and store at -20°C or colder (without azide).