QUANTITATIVE-DETERMINATION OF IGG AND IGA ON SPERM FROM INFERTILE PATIENTS WITH AND WITHOUT ANTISPERM ANTIBODIES

Immunoglobulins on patients sperm were determined by an ELISA techniqu e, modified from the RIA described by Haas and D'Cruz (Am J Reprod Imm unol, 1989; 20:37-43), i.e., suspensions of washed sperm (40, 20, 10, and 5 mill/ml) were added to a dilution of peroxydase-labelled anti-Ig G or anti-IgA, and after incubation the supernatants were transferred to cups in microtrays, coated with IgG or IgA, respectively. After inc ubation and washing ELISA reaction was carried out. Known amounts of I gG and IgA were processed in the same way to obtain a standard curve, allowing the Ig on the sperm to be expressed in ng/mill sperm. Ejacula tes with increased viscosity revealed high values, irrespective of MAR -results and in some cases the same was true for samples with large nu mbers of non-spermatozoal cells (NSC). However, among 48 samples from men from infertile couples with negative MAR, > 20 mill sperm/ml, norm al viscosity, and a ratio between sperm and NSC > 5, the median for Ig G was 0.2 ng/mill sperm, 90% had less than or equal to 0.8 ng/mill spe rm, and the highest value recorded was 1.9 ng/mill sperm. For IgA the median was 0.5 ng, 90% of the 47 samples contained less than or equal to 1.9 ng, and the highest value was 3.1 ng/mill sperm. The values for sperm from patients with a positive MAR, but without free antibodies in seminal plasma, were generally within the normal range. In contrast , increased values were recorded for most of the patients with free an tibodies in seminal plasma, up to 4.2 ng/mill sperm for IgG and up to 12.5 ng/mill sperm for IgA.