In-vitro processing of sperm with autoantibodies: analysis of sperm populations.

Ejaculates from 51 infertile men with significant levels of anti-sperm antibodies were submitted to processing in vitro in order to increase the number of antibody-free spermatozoa. Rapid removal and washing of spermatozoa from antibody-containing seminal fluid resulted in a variable decrease in IgG and/or IgA binding; only IgG binding was significantly reduced. Those spermatozoa were allowed to swim-up into an overlaying medium to select those with the best progression. Unexpectedly, in the post-migration samples (PM), the proportion of progressively motile spermatozoa coated with IgG and IgA antibodies increased significantly. An efficient selection of antibody-free spermatozoa was achieved prior to swim up migration by immuno-binding to polystyrene Petri plates coated with anti-human immunoglobulin antibodies. Non-adherent populations were depleted of 27-100% of IgG and IgA antibody-coated spermatozoa. After migration, the percentages of antibody-coated spermatozoa of those populations (PMP) remained low. The comparison between PM and PMP populations shows that immunobinding increases the number of motile antibody-free spermatozoa. The fertility potential of both sperm populations is currently under investigation.