Detection of anti-zona pellucida activities in human sera by the passive hemagglutination reaction

A simple method of detecting anti-zona activities in human sera has been developed by passive hemagglutination reaction ( PHAR ) using bovine erythrocytes as indicator cells coated with purified porcine zona substance. By this test, 8 of 88 serum samples (9.1%) from infertile women gave positive reactions, whereas only 1 of 90 control sera (1.1%). A positive immunofluorescence (IF) assay confirmed the results of the PHAR in seven of the eight positive samples. Positive PHAR and IF on porcine zonae were abolished after adsorption with porcine erythrocytes, but IF on human zonae was retained by four of eight serum samples, indicating the presence of anti-zona autoantibodies in these infertile sera that were directed to an antigen(s) proper to human zonae.