Determination of immunoglobulin classes and subclasses of sperm immobilizing antibodies in infertile women and the inhibitory effect of IgG4 subclass on the sperm immobilizing antibody activity

Flow cytometry study on the effect of serum and peritoneal fluid of women on sperm-binding activity of immunoglobulin G antisperm antibodies

OBJECTIVE

To investigate the influence of sera and peritoneal fluids (PFs) from fertile and infertile women on the binding of antisperm antibodies to the surface of spermatozoa.

DESIGN

The immunoglobulin (Ig) G antisperm antibodies binding to the surface of liver spermatozoa was evaluated after their incubation in antisperm antibodies-positive serum from an infertile male in the presence and absence of female sera or PFs.

SETTING

Russian Scientific Center for Obstetrics, Gynaecology, and Perinatology.

PATIENT(S)

Serum and PF samples from fertile and infertile women; antisperm antibodies-positive serum from infertile men; high-quality fresh semen from healthy donors.

INTERVENTION(S)

Serum samples were obtained from fertile and infertile women and from infertile men. Peritoneal fluids were collected during routine laparoscopy.

MAIN OUTCOME MEASURE(S)

The proportion of spermatozoa positive for IgG antibodies and the quantity of antisperm antibodies on the sperm surface measured by flow cytometry (FCM).

RESULT(S)

The addition of sera from fertile or infertile women with endometriosis or pelvic adhesion disease to an IgG antisperm antibodies-positive male serum resulted in significant inhibition of the antisperm antibodies binding to the sperm surface.

CONCLUSION(S)

Sera of fertile as well as infertile woman contain factors that block IgG antisperm antibodies binding to the surface of live spermatozoa.

Characterization of anti-sperm antibodies and their coding cDNA sequences by Epstein-Barr virus transformed B cell lines from lymphocytes of infertile women possessing anti-sperm antibodies

Epstein-Barr virus (EBV)-transformed B cell lines that produce human antisperm antibodies were established using peripheral blood lymphocytes (PBLs) from infertile women with sperm immobilizing antibodies in their sera. We obtained three stable cell populations (designated B1, B2, D5) of transformed PBLs originating from three different patients. They produced IgM sperm-reacting antibodies directed against the tail of live, methanol-fixed and NaIO4-treated human spermatozoa. The established antisperm antibodies recognized noncarbohydrate sperm membrane antigens with different specificity and distribution in the male reproductive system. Antisperm antibody-B2 corresponding antigen appears to be specific for the male reproductive system. This antigen is excreted from the epithelial cells of the ductus epididymidis and bound to the spermatozoa in the lumen of the ductus. Antisperm antibodies B1 and D5 corresponding antigens were expressed on the spermatozoa in the seminiferous tubules and were common to the secretions of the ductus epididymidis, prostate and some other somatic organs. The cDNA of the immunoglobulin heavy chain genes were analyzed by reverse transcription polymerase chain reaction (RT-PCR) using RNA extracted from these clones. The immunoglobulin heavy chain cDNA sequences of these antisperm antibodies showed extremely high homology to previously reported immunoglobulin germline DNA sequences, implying that these antisperm antibodies might be natural autoantibodies rather than antibodies stimulated by external antigen.

Autoantibodies to decondensed sperm nuclear deoxyribonucleic acid in patients with antisperm antibodies and systemic lupus erythematosus detected by immunofluorescence flow cytometry

OBJECTIVE

To evaluate a flow cytometric method to detect and quantitate serum anti-DNA antibodies using unfixed, swollen and decondensed human sperm nuclei and to examine the relationship between antibodies against sperm surface antigens to the presence of antibodies against nuclear antigens.

DESIGN

Serum IgG and IgG subclass antibodies to decondensed sperm nuclei were detected by indirect immunofluorescence (IIF) flow cytometry. Sera were screened by IIF for anti-double-stranded DNA antibodies using the protozoan Crithidia luciliae as the substrate and for antinuclear antibodies using human epithelial (HEp 2) cells, respectively. All sera were assessed for antibodies against the sperm plasma membrane by an indirect immunobead test.

SETTING

Infertility laboratory at the University of Oklahoma Health Sciences Center and rheumatology laboratory at the Oklahoma Medical Research Foundation.

PATIENTS

Sera from 33 antisperm antibody-positive patients (5 subgroups), 33 patients with systemic lupus erythematosus (SLE; 6 subgroups), and 20 normal controls were selected.

RESULTS

IgG antibodies against decondensed sperm nuclear DNA were detected in 11 (33.3%) of 33 antisperm antibody-positive patients versus 14 (42.4%) of 33 patients with SLE. Anti-DNA antibodies were most prevalent in vasectomized men and in antisperm antibody positive women with SLE. In the sera from patients with SLE, the presence of the anti-nuclear ribonucleoprotein antibody was associated with the presence of sperm head-directed antisperm antibodies. Anti-double-stranded DNA antibodies were found in 6 (18.1%) of 33 sera from patients with antisperm antibody and 17 (51.5%) of 33 sera from patients with SLE. Antinuclear antibodies were found in only 9 (27.2%) of 33 sera from patients with antisperm antibody and 30 (90.9%) of 33 sera from patients with SLE. All 20 of the control sera gave negative results in the three tests. Serum IgG reactivity to sperm nuclei was predominantly of the IgG1 and IgG3 subclasses.

CONCLUSION

Anti-DNA is frequently found in either patients with antisperm antibodies or patients with SLE. Our results indicated that decondensed sperm nuclei can provide a specific substrate for screening serum anti-DNA antibodies.

IgG subclass distribution of anti-hCG and anti-diphtheria toxoid antibodies in women immunized with a beta-hCG based immunocontraceptive vaccine

IgG subclass distribution of antibodies against human chorionic gonadotropin (hCG) and diphtheria toxoid (DT) was determined in the sera of women recruited into Phase II clinical trials of a beta-hCG based immunocontraceptive vaccine. Serum samples from 30 different individuals were analyzed. Anti-hCG antibody response was predominantly of IgG1 subclass, with a mean titer of 537.94 +/- 560 antibody units (AU). The other 3 subclasses showed considerably lower mean levels (IgG2, 16.46 +/- 8.33; IgG3, 3.22 +/- 8.48; IgG4, 56.65 +/- 82.60 AU). A good correlation was observed between the anti-hCG IgG1 antibody titers (r = 0.57, P < 0.01) and the bioneutralization capacity of sera. However, bioneutralization capacity of the sera from subjects capable of inducing IgG4 response was not significantly different from subjects not showing IgG4 antibodies. Similarly, a dominant IgG1 response was observed against diphtheria toxoid (DT) which has been used as one of the carrier proteins in the vaccine.