The clinical relevance of classes of immunoglobulins on spermatozoa from infertile and vasovasostomized males.

Following reversal of vasectomy, conceptions occur even when antisperm antibodies are present in the seminal plasma, but this is most unusual in men with similar titers of such antibodies who are spontaneously infertile. To clarify the differences between antisperm antibodies occurring in infertile men and those associated with vasectomy reversal, we have studied 23 spontaneously infertile men and 22 men who underwent vasectomy reversal, all of whom had antisperm antibodies detected in seminal plasma by the same tray agglutination test. The class of antibody on spermatozoa was defined by a double-antibody technique using diluted rabbit anti-human IgG, IgM, or IgA or secretory component, followed, after washing, by 125I-labeled donkey anti-rabbit Ig. The results have shown that similar amounts of IgG and IgM were present on the spermatozoa, but infertile men had significantly more IgA and especially more secretory component than men who underwent vasectomy reversal. This was associated with significantly greater impairment of penetration of cervical mucus in the former group. It appears that the type of antibody on the spermatozoa may vary according to the stimulus for its production.