Do autoantibodies to sperm reduce fecundity? A mini-review in historical perspective.
OBJECTIVE
The paradox that early studies of antisperm antibodies in men showed a strong correlation between titers of circulating antibodies (essentially immunoglobulin [Ig] G) and reduction in conception rates, whereas more recent studies have indicated that the antifertility effect is mainly (or exclusively?) associated with IgA antibodies, impairing sperm migration through cervical mucus, was studied.


METHODS
Relevant literature focusing on antibodies on ejaculated sperm was analyzed.


RESULTS
Direct mixed antiglobulin reaction (MAR) and immunobead-binding tests are excellent and sensitive techniques for demonstrating antibodies of the IgG and IgA classes on sperm, and they have revealed that IgA antibodies are, with very rare exceptions, found only when IgG antibodies are also present. However, these tests tell little about the amounts of antibodies present, and attempts to measure quantitatively the amounts of Ig on sperm have indicated higher levels of IgA than IgG (despite the strongest MAR reactivities for IgG).


CONCLUSIONS
The patients with high levels of IgA to their sperm are mainly men with strong immune responses and, therefore, also high antibody titers in serum. Apparently, the locally produced IgA antibodies reach the sperm and occupy the binding sites before the main bulk of IgG reaches the seminal compartment with the prostatic fluid.
Hjort
T
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Department of Medical Microbiology and Immunology, University of Aarhus, Denmark.
D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D005298:Fertility / Q000276:immunology*; D006801:Humans; D008297:Male; D013094:Spermatozoa / Q000276:immunology*
D001323:Autoantibodies