Autoantibodies against spermatozoal antigens detected by immunoblotting and agglutination. A longitudinal study of vasectomized males.

ABSTRACT

Sera taken pre- and post-operatively at regular intervals within a year from 16 men undergoing vasectomy were analysed for autoantibodies against spermatozoal proteins by immunoblotting. The reaction patterns were compared with the results of sperm agglutination tests. Immunoblotting revealed the presence of autoantibodies against various spermatozoal polypeptides in all sera taken pre-operatively and post-operatively. On average, seven polypeptides showed reaction. During the post-operative period two patients developed spermatozoal agglutinins in moderate titers (greater than 16) but in immunoblotting no change in band reactivity was observed for these two patients. However, scanning of the immunoblotting results revealed that one of the patients, although without sperm agglutinins, during the post-operative period showed an increasing band colouring of a polypeptide of Mr 31,500, reflecting an increased level of the corresponding antibodies.

ABSTRACT

PIP Sera taken at the postoperative intervals of 10-21 days, 1-2 months, 3-5 months, 9-12 months from 16 men undergoing vasectomy were analyzed for autoantibodies against spermatozoal proteins by immunoblotting. After recording the natural pattern of antibody binding, qualitative and quantitative changes were identified and related to the sperm agglutinins. On average, an observation time of 6 months was obtained. All the men had been proven fertile prior to surgery and had azoospermia after surgery. Sera also were taken from 7 normal controls with at least 3 month intervals during 1 year to determine whether changes of the spectrum of the antibody specificities occurred. A figure shows an immunoblotting analysis of IgG autoantibodies to SDS-PAGE separate spermatozoal antigens with 5 serum samples from 1 person taken preoperatively and 1, 2.5, 3, and 8 months after vasectomy. Even prior to the operation at a time when the patient was fertile, an IgG binding was demonstrated. This observation held true for all 16 vasectomized males and the group of 7 controls. The staining pattern of the consecutive serum samples was constant. Only 2 patients reacted after vasectomy with a moderate increase in antibody titre (greater than 16), but neither of these patients, nor the rest of the group, developed new bands in immunoblotting for IgG. The immunoblotting analysis for IgM antibodies in sera from the 2 men with sperm agglutinins did not show variation with time. The 7 control men did not show any qualitative or quantitative changes in their IgG reaction pattern during the observation period nor did they reveal the presence of any autoantibodies in the agglutination tests. Scanning of the immunoblotting results revealed that 1 of the patients, although without sperm agglutinins, showed an increasing band coloring of a polypeptide of Mr, 31,500 during the postoperative period, reflecting an increased level of the corresponding antibodies.