Immunoglobulin Binding Factor of Seminal Plasma: A Secretory Product of Human Prostate

To determine the source of the immunoglobulin binding factor (IBF) in seminal plasma, extracts of testis and accesory male sex organs were prepared and analyzed by sodium dodecyl sulfate polyacry-lamide gel electrophoresis (SDS-PAGE) and immunoblot. The detection reagents used were human and mouse serum Ig, monoclonal anti-Leu 1 Ib antibodies, and polyclonai rabbit anti-IBF antibodies. Of the tissues examined, only the prostate, including benign hypertrophy and adenocarcinoma, contained IBF. These findings suggest that IBF is a secretory product of the prostate.