No abstract

Approximately 40% of the prostate-specific antigen (PSA) purified from seminal fluid comprises cleaved or fragmented forms of PSA. These fragments are observed by reduced SDS-PAGE and have been identified in preparations of purified seminal plasma. The comparative analysis of 53 antibodies, submitted to an international PSA Workshop, with different PSA variants was studied using SDS-PAGE and Western blotting. Six different patterns of reactivity were observed which may reflect different epitopes recognized by this panel of antibodies. Additional antibody studies to nonreduced intact PSA suggest the epitopes are conformation-dependent.