Immunoglobulin class and regional specificity of antispermatozoal autoantibodies blocking cervical mucus penetration...

The immunoglobulin class and regional specificity of sperm antibodies was analyzed in relation to in vitro cervical mucus penetration using a capillary test. There was a highly significant (chi 2, P less than 0.001) association of strong (greater than or equal to 95% sperm coated) immunobead test (IBT) results for sperm-bound antibodies of IgA immunoglobulin class with poor (less than 3.0 cm/2 h) mucus penetration. There was also a significant (P less than 0.01) association between poor penetration and the presence of antibodies on the sperm tail mainpiece. In contrast, IgG class antibodies did not show any significant association with poor penetration. These results confirm and extend previous work and imply that development of a male antispermatozoal vaccine that inhibits mucus penetration must involve stimulation of local IgA response rather than systemic antibody levels.