Induction of infertility in female rats after active immunization with 24 kD antigens from rat testes

A unique polyvalent antiserum against whole washed human sperm was used previously to identify groups of antigens on spermatozoa. The antiserum, designated as Antiserum I, recognized a 40 kD antigen in human sperm extracts. Antiserum I caused agglutination of human sperm and prevented interaction of mouse sperm and oocytes. This serum also recognized a band of 24 kD in rat testicular cytosol. In the present study this group of 24 kD proteins was used as an antigen preparation to actively immunize female rats. Immunization was carried out with two different adjuvants: nor-muramyl dipeptide and SPLPS (a thyalated derivative of lipopolysaccharide). Both groups of animals showed significant antibody titres as detected by indirect immunofluorescence and by sperm agglutination tests. In both groups over 80% of the animals remained infertile, compared to 13% of the controls. It is concluded that a group of antigens in rat testes recognized by Antiserum I offer promise as candidates for a contraceptive vaccine.

Characterization of a monoclonal antibody against a 24KD antigen from rat testis important for fertility regulation

Monoclonal antibodies were raised against a 24KD antigen from rat testicular cytosol which was previously shown to produce antibody titres in rats with inhibitory effect on fertility. Of the 20 hybridoma clones selected for study, one clone HS-D5 was finally chosen for characterisation as it proved to be functionally promising. The clone was secreting IgM type of antibody. It produced strong agglutination of human sperm and prevented binding of hamster sperm to hamster oocyte. In localization studies it identified the acrosome of sperm of multiple species. Western blots with rat testicular cytosol and human sperm extracts showed a strong band at around 24KD with HS-D5. On Western blots from two dimensional gels, HS-D5 identified multiple spots at the region of 24KD. The mechanism of action of the antibody seemed to be at the level of interaction of the oocyte and spermatozoa.

Results of IVF attempts in patients with unexplained infertility

From January 1986 to July 1987, 143 patients with unexplained infertility (UI) following 217 IVF attempts were studied and randomly assigned for statistical analysis to be compared with 434 tubal infertility (TI) patients undergoing 748 IVF attempts. The age of patients, previous pregnancy history and stimulation protocols were identical in both groups. In comparison with tubal patients, IVF attempts on the UI group were characterized by the same rates of cycle failure, mean number of oocytes retrieved per cycle, a lower fertilization rate (45.7% UI/59.8% TI) (P less than 0.01) and no difference in cleavage and nidation rates. However, a decrease in the pregnancy rate/attempt (13.8% UI/19.5% TI) tended towards a significant value (P = 0.06). Although the semen parameters were found to be in the normal range during the previous fertility screening in both groups, the incidence of at least one abnormality (count less than 20 X 10(6)/ml, and/or total motility less than 30% and/or abnormal forms greater than 75%) on the day of insemination was found to be significantly higher in UI (20%) than in TI (11%) patients. Moreover, 25% of UI patients did not fertilize any oocytes inseminated, whatever the number of oocytes retrieved. This rate of failed fertilization was significantly lower (9%) in tubal patients. The oestrogen response profiles were similar in both groups, analyzed according to the stimulation protocols.(ABSTRACT TRUNCATED AT 250 WORDS)

Fibronectin levels in male ejaculate and evidence for its role in unexplained infertility

Vasovasostomy has become a popular and highly successful method of restoring fertility to those who have undergone a vasectomy. However, there is a high correlation between vasostomy and antisperm antibody production leading to spontaneous sperm agglutination and immobilization. There is still considerable disagreement on whether antibodies are the primary causative agent. Our study provides evidence that fibronectin, a ubiquitous glycoprotein whose major function is cell-to-cell adhesion, could be a "subfertility" factor and contribute to male "unexplained infertility." Semen from control, random, and vasovasostomy populations was studied using a sophisticated enzyme-linked immunosorbent assay (ELISA). The results show that fibronectin is significantly present in all groups. The mean concentrations (micrograms/mL) were 753.9 for control, 566.4 for random, followed by significantly higher 1267.3 for the vasovasostomy group (p less than 0.05). The spermatozoa were assayed for bound fibronectin by flow cytometry. The mean percentage of cells bound after background subtract was 29.7 for control and 48.2 for the vasovasostomy group; the difference was significant (p less than 0.05). We conclude that fibronectin is present in semen and bound to sperm cells in great concentrations for individuals having undergone surgical insult and may contribute to male infertility particularly by sperm agglutination.

Circulating antisperm antibodies and fertility prognosis: a prospective study

In a prospective study performed on 235 couples with long-standing infertility (median 5 years), circulating antisperm antibodies (ASA) were determined with both a standard trayagglutination test (TAT) and a radioimmunoassay (RIA). Serum levels were correlated with results of sperm analysis (SA), postcoital testing (PCT) and in-vitro sperm--cervical mucus penetration testing (SCMPT), performed with cervical mucus and spermatozoa of patients and in parallel with material of fertile donors. A simultaneous microbial screening included Chlamydia trachomatis, mycoplasmas, Herpes simplex virus, gonococci, other potentially pathogenic aerobic and anaerobic bacteria and yeasts. The pregnancy rate 12 months after determination of ASA in the serum samples was 27% (64/235). Between ASA-positive and -negative male and/or female patients (TAT as well as RIA), no significant difference was found for any of the tested variables of SA, PCT, crossed SCMPT and colonization of genital secretions with microorganisms. Patients who later achieved pregnancy and those who did not did not differ with regard to serum antibody status (TAT as well as RIA). The findings suggest that the clinical significance of circulating ASA determined with the currently available methods is low. ASA in serum samples of infertile female and/or male patients do not influence the fertility prognosis.

Interrelationships among semen characteristics, antisperm antibodies, and cervical mucus penetration assays in infertile human couples

Semen characteristics, antisperm antibodies, and cervical mucus penetration studies were analyzed in 754 couples and 95 men undergoing infertility evaluation. The means for the different semen/sperm variables were within ranges published for fertile men. Ages of the men ranged from 22 to 55 years and accounted for a small amount of variation. Sperm counts were lowest in September, December, and January, and highest in April, May, October, and November. Of the sperm characteristics, morphology appeared to be associated with the most other variables. Specimens with more than 50% abnormal sperm forms were overall of significantly poorer quality in terms of sperm counts, motility, forward progression, and ability to penetrate cervical mucus. Antisperm antibodies (agglutinating and immobilizing) were detected in the serum samples of 19.0% of the men, 20.4% of the women, and 32.8% of the couples where one or both partners were positive. Agglutinating antibody titers were significantly correlated between partners. Serum titers of antisperm antibodies were associated with decreased sperm counts, motility, forward progression, and normal forms (immobilizing antibodies). Multiple correlation analysis indicated significant independent effects of sperm concentration, motility, forward progression, and antibodies on sperm-cervical mucus penetration scores of the men. In women, cervical mucus penetration was adversely affected by the presence in the serum of sperm agglutinating antibodies and of immobilizing activity in the cervical mucus.

[Unilateral testicular torsion. Effect on the contralateral testis]

The unilateral testicular torsion produce alteration of contralateral testes, with a frequence of sterility and alteration sperm bigger than normal population. The great differences report for various authors in the works make necessary to know better the pathogenesis of the testicular torsion about the fertility. With the aim to study this aspect, we carry out this experimental work in that animals with testicular torsion, although with individual results very different, have, again the animals with sham intervention, less number of sperm (P less than 0.001), with less time of survivorship (P less than 0.001), bigger percentage of precocious agglutination and abnormal shape (P less than 0.001) and bigger quantity of immobile sperm. These alteration as adult animals, but they are bigger in the late.

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.

Identification of sperm antigens that regulate fertility

Polyclonal antisera were generated in rabbits against human sperm extracts. Out of many such antisera, one was selected (antiserum I) because it recognized relatively few antigens on Western blots. Antiserum I identified immunostainable material on the acrosome of human, monkey, rabbit, hamster, rat and mouse sperm. A detailed histochemical study using rat testes showed that the antigen was detectable on early spermatids and sperm, but not on less mature germ cells. Immunohistochemistry at the electron microscope level localized the antigen on the plasma membrane of rat sperm. In Western blots using human sperm extracts, the antibody recognized a major band with an apparent molecular weight (MW) of 40,000 and minor bands at 43,000 and 72,000. With extracts of monkey sperm and rat testicular cytosol, antiserum I recognized antigens of 69,000 and 23-24,000, respectively. Functionally, antiserum I produced strong agglutination of human sperm. It also prevented attachment of mouse sperm to mouse oocytes in vitro and reduced fertility when administered to female mice. These results suggest that antiserum I can be used as a possible reagent for selecting sperm antigens as components of a contraceptive vaccine.

A direct immunofluorescence test for the detection of sperm surface bound antibodies. Comparison with sperm agglutination test, indirect IF test and MAR test

A direct immunofluorescence (DIF) test using sperm suspensions and F (ab')2 antisera was carried out on 30 patients with sperm-agglutinating (SA) activity and on 25 negative controls. Its results were related with the occurrence of SA activity in serum and seminal plasma, with the results of the indirect IF test and those of the direct IgG-MAR test. DIF test gave positive results in all patients with significant serum SA activity, even when it was undetectable in seminal plasma, except in 2 cases with serum IF-reactivity for IgM, and negative results in all controls. IgG were involved in IF-reactivity in 88.4% of positive cases and IgA in 42.3%. IgA were always found in association with sustained SA activity in seminal plasma. In these cases the IgG-MAR test might not result strongly positive, in spite of the high titre of SA activity in semen.

Improved penetration of spermatozoa into uterine fluids of women with abnormal postcoital tests

Cervical mucus-uterine fluid cross-penetration of husbands' and control sperm was assessed in 13 couples with poor or negative postcoital tests. Cervical mucus scoring and tray agglutination test identified six women with sperm-agglutinating antibodies and seven women with cervical dysmucorrhea. All males were normozoospermic, with penetration into control cervical mucus and control uterine fluids. Control sperm penetrated into cervical mucus and uterine fluids of three and five of the women with sperm-agglutinating antibodies and cervical dysmucorrhea, respectively. Penetration of husbands' spermatozoa into uterine fluids of patients with sperm-agglutinating antibodies was lower than that of control semen (P less than .05). Control and husbands' sperm penetration into uterine fluids of women with cervical dysmucorrhea were identical. In both groups, husbands' and control sperm penetrated uterine fluids more frequently than cervical mucus (75 versus 12%; P less than .001). On a six-month follow-up and midcycle intrauterine inseminations, six patients (46%) conceived. We conclude that uterine fluids of patients with sperm-agglutinating antibodies and cervical dysmucorrhea may provide a better milieu for spermatozoa than cervical mucus. This observation suggests a rationale for intrauterine inseminations to achieve pregnancy.

Vasectomy-induced autoimmunity: monoclonal antibodies affect sperm function and in vitro fertilization

A panel of sperm-reacted monoclonal auto-antibodies developed from spleen cells of vasectomized mice (BDF1) were characterized. Immunogenic antigens were mainly located on the acrosome, midpiece and principal piece. All of the monoclonals were IgM; three demonstrated a multispecific reaction with testis and/or epididymis antigen extracts by immunoblotting. Immunobead studies indicated that most of the antibodies were to surface molecules, a finding supported by the observation that five of the seven antibodies caused complement-mediated immobilization (although not sperm agglutination) of mouse sperm. In vitro fertilization was significantly impaired when antibodies (Vx5, 8 and 10) were added to the sperm prior to exposure to the eggs. Furthermore, passive immunization with Vx5 antibody reduced in vivo fertilization. Our findings indicate that vasectomy-generated antibodies can reduce sperm function in vitro and in vivo.

Evaluation of the direct and indirect mixed antiglobulin reaction with latex particles for the diagnosis of immunological infertility

The direct Mixed Antiglobulin Reaction (MAR test) is a simple method for the detection of auto-antibodies attached to spermatozoa in fresh semen. The test was improved by using IgG-coated latex particles (SpermMAR) instead of coated red blood cells. A positive direct MAR test with adherence of latex particles to 40% or more of the motile spermatozoa was found in 16 out of 312 men (5%) consulting for infertility, but never in fertile controls. The percentage of motile spermatozoa reacting with the coated latex particles was correlated significantly with the serum titre of sperm agglutinins assessed by the tray agglutination test. The direct MAR test on semen was highly specific but rather insensitive, particularly if the serum titre of agglutinins was low. The same kit (SpermMAR) can be used to detect circulating sperm antibodies in serum of male or female patients with the indirect mixed antiglobulin reaction. The indirect MAR test discriminated clearly between serum with low (less than 1/32) or high (greater than 1/32) titres of circulating agglutinins assessed by the tray agglutination test. Considering their simplicity and accuracy, both the direct test on semen and the indirect spermMAR test on serum should be included in the routine evaluation of the infertile couple.

The immunobead technique: an indicator of disturbed sperm cervical mucus interaction

A group of 20 couples with repeatedly poor post coital tests (PCT's) where no coital disorders or cervical mucus abnormalities were present, were included in the study. The results of the Direct Immunobead (IB) and Tray-agglutination tests were compared with the results of the sperm-cervical-mucus-contact (SCMC) and post coital tests (PCT's) of each couple in order to determine the sensitivity, specificity and predictive value of the Direct IBT as a screening test for sperm antibodies. The positive predictive value of the IBT was 80%. It was also clear that a strong positive SCMC-T result correlated with agglutinating antibodies in the semen or seminal plasma. In conclusion, the IBT is a sensitive, specific and predictable test for sperm antibodies.

Involvement of fertilization antigen (FA-1) in involuntary immunoinfertility in humans

Sera from immunoinfertile patients (n = 32) and fertile controls (n = 20) were analyzed for cross-reaction with a purified and characterized sperm-specific glycoprotein, the fertilization antigen (FA-1), employing an enzyme-linked immunosorbent assay. The immunoinfertile sera demonstrated a strong reaction with FA-1 when compared with fertile control sera. There was no correlation between the reaction of sera with FA-1 and the titers obtained through the sperm agglutination technique and the sperm immobilization technique. Immunoinfertile sera showed binding with the protein bands in the regions corresponding to FA-1 on Western blots involving sodium deoxycholate-solubilized human sperm. Antigens isolated with immunoaffinity chromatography involving immunoinfertile sera also demonstrated antigen bands corresponding to FA-1 in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Of the seven immunoinfertile couples, three that had antibodies to FA-1 in the male as well as female partners demonstrated a block of fertilization (IVF) due to antibodies bound on the sperm surface. The anti-FA-1 antibody activity was detected in serum as well as in follicular fluid and seminal plasma. Immunoinfertile sera that showed an inhibition of human sperm penetration of zona-free hamster ova showed a significant (P less than 0.001) increase in penetration rates after absorption with FA-1. These results indicate that sera from immunoinfertile patients had antibodies reacting with FA-1, and these antibodies are involved in the fertilization process.

Sperm retention cysts in the efferent duct and testicular atrophy of TE inbred rats

Sperm retention cysts were observed in the efferent duct of TE inbred rats at 15 weeks of age. Spermatozoa agglutinated in the efferent duct with destruction of the epithelium. Testicular weight increased or decreased. Diameter of the seminiferous tubules was enlarged in testes that increased in weight and germinal cells degenerated in the atrophied testes. After 30 weeks of age, the tubules of the efferent duct were sometimes replaced by scars and testicular atrophy became more frequent. In 3 out of 5 normal rats united by parabiosis with TE males for 25-27 days, cysts occurred in the efferent duct.

Serum sperm agglutinating antibody formation in vasectomized men treated with dexamethasone

The effect of immunosuppression with dexamethasone on sperm antibody formation following vasectomy in men was determined. Vasectomized men were treated with dexamethasone (4 mg) tablets starting two days prior to vasectomy and each day thereafter for a total of eight days for a total dose of 30 mg. There was no significant difference in serum sperm agglutinating antibody, cholesterol, triglycerides, or lipoproteins between the dexamethasone and placebo groups. The finding that immunosuppression at the time of vasectomy did not inhibit sperm antibody formation in man was surprising because in a similar study with Cynomoglus monkeys treatment at the time of vasectomy with dexamethasone inhibited sperm antibody development. The difference between the two studies may be that in monkeys sperm antigen presentation comes at the time of vasectomy and therefore immunosuppression at this time can prevent an immune response, but in man sperm antigen presentation comes at some later time following vasectomy. This species difference in sperm antigen presentation following vasectomy in man compared to monkeys may affect subsequent atherosclerosis development and explain why no cardiovascular disease is found in man following vasectomy.

The relationship of infection with Chlamydia trachomatis to the parameters of male fertility and sperm autoimmunity

The relationship of past exposure to C. trachomatis to the parameters of male fertility was examined in men from infertile couples whose wives had no known female fertility factors. In this population, the frequency of C. trachomatis antibody was low. Past infection with C. trachomatis was associated with a history of nonspecific urethritis, and with the presence of sperm agglutinating antibodies in serum. We found no difference in the seminal fluid analyses, physical examinations, or sperm penetration assays of the men with or without chlamydial antibody.

The antibody from an infertile woman that induces sperm agglutination interacts with rat testicular cells and sperm

The serum obtained from an infertile woman induced a specific head-to-head agglutination of human and rat sperm. The immunoglobulin G (IgG) fraction of the serum was obtained and found to interact with the proteins of rat sperm in testis and epididymis. Using an indirect immunofluorescent method with rat sperm from vas deferens, we determined that the antibody recognized the protein on the convex and concave regions of the acrosome and over the entire tail. However, with testicular spermatozoa, the antibody recognized only the distal end of the tails. In paraffin sections of adult rat testis, sperm tails located at the luminal region of the seminiferous tubules stained intensely. Weak but significant staining also occurred on late spermatids. In the epididymal sections, staining was restricted to spermatozoa in the lumen. On the other hand, sections of testes from 25-day-old rats containing spermatogonia and early spermatocytes had a completely negative reaction. Testicular somatic cells, including Sertoli cells, peritubular myoid cells and interstitial cells, did not stain. To identify the testicular protein interacting with the antibody, adult rat testis proteins were prepared and analyzed by a sodium dodecyl sulfate-polyacrylamide gel electrophoretic (SDS-PAGE) immunoblot technique. The antibody interacted with a protein with an estimated molecular weight of 82,000 in the testicular homogenate and particulate fraction, whereas the reaction was considerably weaker with the testicular cytosol fraction.