Characterization ofspermantigens reacting with humanantisperm antibodies

SUMMARY Antibodies reacting with humanspermatozoa havebeendetected byvarious immunologicaltechniques intheseraofsubfertile men.Different patterns ofspermagglutination are observed withdifferent sera, either head-to-head, tail-to-tail, ortail-tip-to-tail -tip. Differences havebeendetected between theclinically relevant antibodies inspontaneously infertile males andtheless important antibodies inmales whohaveundergone reversal of vasectomy. Ithasbeensuggested thatthevariations inagglutination patterns aredue either todifferent classes ofantibody ortobinding ofantibody todifferent antigens. Inthe present study immunoblotting techniques wereusedtocharacterize thereactivity of solubilized spermproteins withserumsamples exhibiting different modesofsperm agglutination. Thisinvolved theelectrophoretic transfer ofproteins fromSDSgels to nitrocellulose sheets followed byoverlay withserumantibody. Using these techniques we haveattempted tocharacterize theantigens ofspermatozoa which react withserafrom bothspontaneously infertile andvasovasostomized men.Theresults showedthat although antisperm antibodies bindtodiscrete andsperm-associated antigens, there isno substantial difference between theantigenic patterns observed withantibodies producing different types ofspermagglutination. Neither theantigens detected, northeintensity of reaction showed significant differences although there wasatendency forhead-to-head agglutinating antibodies toreact morestrongly withthehigher molecular weight antigens. Moreover, although withsequential serumsamples thepatterns ofagglutination may change, theantigenic pattern remains unchanged.