Further characterization of the nonimmunoglobulin sperm-agglutinin found in some human sera

A comparison is made between some properties of immunoglobulin and nonimmunoglobulin sperm-agglutinins. It is found that antisperm antibodies are directed against spermatozoal components and bind equally well to viable and nonviable spermatozoa. On the other hand nonimmunoglobulin sperm-agglutinins are directed at both spermatozoal and seminal plasma components and bind to viable sperm. beta-lipoprotein may not be involved in the nonimmunoglobulin sperm-agglutinin found in human sera.