Interaction of seminal plasma proteins with cell surface antigens: presence of a CD4-binding glycoprotein in human seminal plasma.
We report in this paper the presence in the human seminal plasma of a glycoprotein capable of binding to CD4, a surface antigen expressed on the surface of T-cells, macrophages, and sperm cells, which acts as a coreceptor in antigen-mediated T-cell activation and as a receptor for the AIDS virus, HIV-1. This protein, namely gp17 (apparent MW = 17,500 Da), was purified by affinity chromatography and characterized by SDS/PAGE analysis. Its binding to CD4 was inhibited by anti-CD4 mAbs directed against V1, a region of CD4 implicated in the binding to MHC class II antigens and to the HIV-1 envelope protein gp120, but not by mAbs directed against other CD4 determinants. The presence of a CD4-masking factor in human seminal plasma may be relevant to the modulation of maternal immunity at insemination and to the control of sexual transmission of HIV-1.
Autiero
M
M
International Institute of Genetics and Biophysics, University of Naples, Italy.
Abrescia
P
P
Guardiola
J
J
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens / Q000378:metabolism*; D002460:Cell Line; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D007700:Kinetics; D008297:Male; D008970:Molecular Weight; D011506:Proteins / Q000302:isolation & purification / Q000378:metabolism*; D012661:Semen / Q000502:physiology*; D016176:T-Lymphocyte Subsets / Q000276:immunology
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D006023:Glycoproteins; D011506:Proteins