Human sperm proteome: Immunodominant sperm surface antigens identified with sera from infertile men and women

The objective of this study was to identify those immunodominant sperm anti gens recognized by antisperm antibodies (ASA) in the serum samples of infer tile men and women. High-resolution two-dimensional gel electrophoresis was employed to separate human sperm proteins using isoelectric focusing or no nequilibrium pH gradient electrophoresis, followed by PACE. Serum samples f rom 15 infertile male subjects and 6 infertile female subjects that contain ed ASA as assayed by the immunobead binding test (IBT) were analyzed by Wes tern blotting followed by enhanced chemiluminescence (ECL). Serum samples f rom 10 fertile subjects (5 males and 5 females) that were ASA negative by I BT were used as controls. The ECL blots were analyzed by computer scanning to compare the immunoreactivity between serum samples from fertile and infe rtile subjects and to identify the antigens unique to the sera of the infer tile subjects; 98 sperm auto- and iso-antigenic protein spots were recogniz ed by sera from infertile males and females but not from fertile subjects. Based on vectorial labeling with I-125 at the sperm surface, a subset of 6 auto- and iso-antigens was identified as possibly relevant to antibody-medi ated infertility.