Premium
Delineation Between T‐ and B‐Suppressive Molecules From Human Seminal Plasma: I. Partial Characterization of a 180‐kD Protein Inhibiting the B Response to T‐Independent Antigens
Author(s) -
BOUVET JEANPIERRE,
COUDERC JACQUES,
QUAN CANH P.,
PIRÈS RENÉ,
D'AZAMBUJA SOLANGE,
PILLOT JACQUES
Publication year - 1988
Publication title -
american journal of reproductive immunology and microbiology
Language(s) - English
Resource type - Journals
eISSN - 1600-0897
pISSN - 8755-8920
DOI - 10.1111/j.1600-0897.1988.tb00241.x
Subject(s) - in vivo , pronase , in vitro , immune system , microbiology and biotechnology , biology , antigen , t cell , plasma cell , immunogenicity , size exclusion chromatography , antibody , chemistry , biochemistry , immunology , trypsin , enzyme
The immunosuppressive activity of fractionated human seminal plasma (SP) was investigated both in vitro (on human lymphocytes) and in vivo with Balb/ c mice. SP fractionation by dialysis allowed delineation of the major suppressor factors according to their respective sizes—small (< 12kD) or large (> 12kD). In vitro, large molecules were found to suppress the B‐cell proliferative response induced by the Nocardia mitogen, while small molecules suppressed the T‐cell proliferation induced by phytohemagglutinin. In vivo, immunosuppression was obtained almost exclusively on T‐independent responses after preliminary treatments either with unfractionated SP or with large SP molecules. Both type 1 and type 2 T‐independent responses were suppressed, as evidenced by plaque‐forming cells and antibody assays. In contrast, no immunosuppression was found in vivo after treatment by small SP molecules. Purification of the B‐cell suppressor by gel filtration and high‐performance liquid chromatography, as well as by preparative isofocusing, indicated that its molecular weight was 180 kD and its isoelectric charge was between pH 5 and 6. This factor is a protein, as evidenced by pronase digestion. A possible role for this molecule in the protection of sperm against the female immune system is discussed.