BOVINE SEMINAL PLASMA CONTAINS FACTORS THAT ENHANCE LYMPHOCYTE-TRANSFORMATION IN-VITRO

The important immunosuppressive properties of seminal plasma have sign ificant functions in the processes of reproduction. They mask the pres ence of an immunostimulating activity. From bovine seminal plasma two active factors have been isolated and characterized with marked enhanc ing activity for in vitro PHA-dependent lymphocyte transformation. The y have inosine and hypoxanthine structures, as confirmed by UV absorpt ion profiles, TLC, mass spectrometry, HPLC patterns, behavior to enzym atic treatments, and breaking of purine ring after acid treatment. Nev ertheless, their biological activities are about two orders of magnitu de higher than those of commercially available inosine and hypoxanthin e standards. Biological activities became practically identical when t hese were processed (HPLC) in the same way as native molecules. A stud y to explain such a discrepancy is in progress.