Post-vasectomy autoimmunity to protamines in relation to the formation of granulomas and sperm agglutinating antibodies.

The development of antibodies reacting with nuclear antigens was studied in sera from vasectomized men and monkeys (obtained at intervals of up to 2 and 4 years, respectively, after the operation), by means of a comparative fluorescence study on swollen nuclei of somatic cells, human and salmon spermatozoa. About 30% of forty-seven vasectomized men developed antibodies to protamines. Also four out of fifteen monkeys, vasectomized with or without ligation, developed antibodies reacting with protamines. In general, when antibodies to the homologous protamines reached higher levels, cross-reactions with salmon protamine could be demonstrated as well. No significant reactions could be detected with somatic nuclear antigens in the sera. Comparison between the results obtained with the immunofluorescence test, the agglutination tests and the clinical findings confirmed the association between the development of immune responses to various sperm-antigens and revealed a coherence of anti-protamine activity and granuloma formation at the site of the operation.