Relationship of epididymal sperm antibodies to their in vitro fertilization capacity in men with congenital absence of the vas deferens

Immunology of the Testis and Male Reproductive Tract

A large body of evidence points to the existence of a close, dynamic relationship between the immune system and the male reproductive tract, which has important implications for our understanding of both systems. The testis and the male reproductive tract provide an environment that protects the otherwise highly immunogenic spermatogenic cells and sperm from immunological attack. At the same time, secretions of the testis, including androgens, influence the development and mature functions of the immune system. Activation of the immune system has negative effects on both androgen and sperm production, so that systemic or local infection and inflammation compromise male fertility. The mechanisms underlying these interactions have begun to receive the attention from reproductive biologists and immunologists that they deserve, but many crucial details remain to be uncovered. A complete picture of male reproductive tract function and its response to toxic agents is contingent upon continued exploration of these interactions and the mechanisms involved.

In vitro and in vivo studies evaluating antisemen antibodies as a potential spermicidal agent in hamsters

OBJECTIVE

To determine the spermicidal activity of antisemen antibodies in the hamster model.

DESIGN

Prospective, controlled study.

SETTING

Advanced preclinical sciences center.

ANIMAL(S)

Subgroups of 10 and 14 golden hamsters.

INTERVENTION(S)

Ex vitro and in vivo treatment of sperm with antisemen antibodies or normal rabbit serum.

MAIN OUTCOME MEASURE(S)

The EC(50) value of antisemen antibodies, the time required for 50% motility loss of progressively motile spermatozoa exposed to antisemen antibodies, the average sperm mitochondrion fluorescence intensity, the rate of fertilization, and the scoring of histologic changes in the hamster vaginal tissue.

RESULT(S)

The EC(50) value of antisemen antibodies was found 70 microg/mL, and the time required for 50% motility loss of progressively motile spermatozoa exposed to antisemen antibodies (at 70 microg/mL) was 5 minutes; for the experimental and control groups, the average fluorescence intensities of sperm mitochondria were respectively 180.28 +/- 82.24 and 309.74 +/- 148.37, the fertilization rates in vitro were 0.09% and 45%, the rates of fertilization with intrauterine sperm injection were 0 and 15.0%. There was a significant difference between two groups. None of the four hamsters that received antisemen antibodies in gel-polyoxyl-40-stearate had epithelial disruption characteristic of inflammation.

CONCLUSION(S)

Antisemen antibodies possess appreciable spermicidal potential, which may be explored as an effective constituent of spermicide.

Incidence of antisperm antibodies in males with systemic autoimmune diseases

PROBLEM

To investigate if systemic autoimmune diseases could be one of the risk factors for developing antisperm antibodies (ASA) in males.

METHOD OF STUDY

Antisperm antibodies in the sera of 70 males with systemic autoimmune diseases and 80 healthy controls were examined, by using the indirect-immunobead test (I-IBT). The sperm immobilization test (SIT) was also performed to detect sperm immobilizing antibodies to the patients who were positive in I-IBT.

RESULTS

Among 70 males with systemic autoimmune diseases, five were I-IBT positives, with incidence of 7.1%. However, no positives existed in 80 healthy males. Compared with the healthy controls, the incidence of ASA in males with systemic autoimmune diseases was significantly higher (P = 0.020). None of these five ASA-positive patients had sperm immobilizing antibodies.

CONCLUSION

The incidence of ASA in males with systemic autoimmune diseases was significantly higher than in the healthy controls. Systemic autoimmune diseases may be one of the risk factors for developing ASA in men.

Value of serum antisperm antibodies in diagnosing obstructive azoospermia

PURPOSE

The requisite presence of active spermatogenesis for antisperm antibody production may be useful in identifying obstructive azoospermia. The diagnostic performance of serum antisperm antibody was evaluated as a test for obstructive azoospermia.

MATERIALS AND METHODS

A total of 484 men with male infertility who had undergone antisperm antibody testing were evaluated. Demographic data, patient history, and followup were recorded. Obstruction was confirmed by surgical exploration. Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios were calculated to quantify diagnostic performance. ROC curves were calculated and compared.

RESULTS

Of 484 men 272 possessed documented obstruction of the vas or epididymis and 212 had documented infertility without azoospermia. The obstructed group had significantly increased antisperm antibody levels compared to the nonobstructed group. IgG, IgA, and IgM were analyzed as diagnostic tests for obstruction. The AUC for IgG, IgA and IgM ROC curves was 0.92, 0.85 and 0.67, respectively. The AUC for serum IgG against sperm tails was 0.92, 0.87 against sperm heads and 0.79 against sperm midpieces. IgG demonstrated the highest sensitivity (85%) with a specificity of 97% (chi-square test p <0.01). IgA possessed the highest specificity (99%), positive predictive value (99%) and positive likelihood ratio (70.0).

CONCLUSIONS

The presence of serum antisperm antibody was highly accurate in predicting obstructive azoospermia, particularly after vasectomy. It can obviate the need for testis biopsy, the current but more invasive and costly gold standard of detection. This allows the surgeon to proceed directly to surgical reconstruction or sperm retrieval after a simple blood test.

Antisperm antibodies and conception

Sperm have been known to be antigenic for more than a century. There is a strong body of evidence that in humans and in other species at least some antibodies that bind to sperm antigens can cause infertility. Therefore, these antibodies are of interest today for two practical reasons. Firstly, the association of the antibodies with infertility means that they must be detected and then the couples treated appropriately. Secondly, because these antibodies can induce infertility they have the potential to be developed for contraceptive purposes in humans and also for the control of feral animal populations.

Association between sperm autoantibodies and enhanced embryo implantation rates during in vitro fertilization

Previous investigations have demonstrated the propensity of strong IgA-class sperm autoantibodies to impede fertilization. However, because there has not been a general consensus on this issue, the aim of this retrospective analysis was to focus on the effects of different levels of IgA-class antibodies on each stage of the IVF procedure. This study has confirmed that high level IgA class antibodies significantly reduce fertilization rates but, unexpectedly, also has shown a very significant improvement in embryo implantation rates in patients with weak to moderate antibody levels. Interlaboratory prospective collaborative studies are being planned to test this preliminary observation more stringently.

Male idiopathic oligoasthenoteratozoospermia

Idiopathic oligoasthenoteratozoospermia (iOAT) affects approximately 30% of all infertile men. This mini-review discussed recent data in this field. Age, non-inflammatory functional alterations in post-testicular organs, infective agents (Chlamydia trachomatis, herpes virus and adeno-associated viruses), alterations in gamete genome, mitochondrial alterations, environmental pollutants and "subtle" hormonal alterations are all considered possible causes of iOAT. Increase of reactive oxygen species in tubules and in seminal plasma and of apoptosis are reputed to affect sperm concentration, motility and morphology. iOAT is commonly diagnosed by exclusion, nevertheless spectral traces of the main testicular artery may be used as a diagnostic tool for iOAT. The following can be considered therapies for iOAT: 1) tamoxifen citrate (20 mg/d) + testosterone undecanoate (120 mg/d) (pregnancy rate per couple/month [prcm]: 3.8%); 2) folic acid (66 mg/d) + zinc sulfate (5 mg/d); 3) L-carnitine (2 g/d) alone or in combination with acetyl-L-carnitine (1 g/d) (prcm: 2.3%); and 4) both carnitines = one 30 mg cinnoxicam suppository every 4 days (prcm: 8.5%). Alpha-blocking drugs improved sperm concentration but not morphology, motility or pregnancy rate. Tranilast (300 mg/d) increased sperm parameters and pregnancy rates in an initial uncontrolled study. Its efficacy on sperm concentration (but not on sperm motility, morphology or prcm) was confirmed in subsequent published reports. The efficacy of tamoxifen + testosterone undecanoate, tamoxifen alone, and recombinant follicle-stimulating hormone is still a matter for discussion.

Diagnosis and treatment of immunologically infertile males with antisperm antibodies

The presence of antisperm antibodies (ASA) can reduce fecundity in both males and females. The present review describes a strategy, established by investigations of the diverse inhibitory effects of ASA on fertility, for the appropriate diagnosis and treatment of infertile males with ASA. For infertile males with ASA, diagnosis using the direct-immunobead test (D-IBT), the postcoital test (PCT) and the hemizona assay (HZA) should be carried out as the basis for decision-making. If the patient with ASA has an abnormal hemizona index, it seems reasonable to advise selecting intracytoplasmic sperm injection-embryo transfer (ICSI-ET) as a primary treatment. However, it has been shown that some immunologically infertile males with normal fertilizing ability established pregnancy by timed intercourse (TI) or intrauterine insemination (IUI). In such patients with ASA having normal hemizona index, TI or IUI can be selected based on the PCT result. Therefore, the treatment strategy for males with ASA is similar to that for infertile males with oligozoospermia or asthenozoospermia. In conclusion, it should be emphasized that a diversity of ASA exists and their effects on fertility in infertile males. Although there is an argument that routine testing for ASA in males is not always necessary, one should be aware that in some cases of failed IUI or IVF, ICSI is selected afterward because of the diagnosis of ASA. (Reprod Med Biol 2005; 4: 133-141).

Diversity of antisperm antibodies bound to sperm surface in male immunological infertility

PROBLEM

The presence of antisperm antibodies (ASA) in males can reduce fecundity, however, relationship between the two is disputed. This study was performed to investigate if there is diversity of ASA bound to sperm surface using immunobead test (IBT) combined with complement dependent sperm immobilization test (SIT).

METHODS

The ASA bound to sperm surface were detected using the direct IBT (D-IBT) in 275 semen samples. In some cases with ASA detected by D-IBT, sperm immobilizing antibodies bound to sperm surface were also evaluated using direct SIT (D-SIT).

RESULTS

The incidence of the immunoglobulin G (IgG), IgA, and IgM classes of ASA detected by D-IBT were 2.5, 1.8, and 0.4%, respectively. Totally, nine (3.3%) infertile men had ASA on the sperm surface. D-SIT was tested positive in four (66.7%) of six cases with ASA assessed by D-IBT.

CONCLUSIONS

Some of the sperm-bound antibodies are associated with complement dependent sperm immobilizing antibodies, indicating that there exists a heterogeneity of sperm-bound antibodies. This result might be one of the reasons for the controversy about the relationship between ASA and immunological infertility in men.

Infertility due to antisperm antibodies

Immunoinfertility is an important problem, involving a significant number of infertile couples. Although the presence of antibodies on sperm has better prognostic value than those in serum or seminal plasma, it may not be the sole authentic evidence of immunoinfertility. Infertility from antisperm antibodies is likely only when they bind to a relevant sperm antigen involved in a specific fertility function. The variance in functional deficits seen in immunologic infertility is most likely related to antibodies directed at different sperm antigens or different class, subclass, or isotypes. Antibodies to FA-1 seem to be of significant importance in human immunoinfertility. In approaching couples with infertility, a high index of suspicion for antibodies is necessary to avoid misdiagnosis. In the optimal situation, all semen analyses should be screened for sperm-bound antibodies, but if this is impractical, testing should be performed on high-risk individuals (Table I). In couples in which the man has sperm-bound antibodies, and in whom there is no identifiable female factor, treatment should be instituted. Most treatments for immunoinfertility have been disappointing because of poor results, adverse effects, or high cost. Corticosteroid therapy has shown some promise in published reports (mostly poorly designed studies), but increase in pregnancy rate is modest and adverse effects may be significant. In our opinion, informed consent should be documented prior to institution of corticosteroid therapy, and subjects should be closely monitored. Advanced reproductive technologies offer a higher safety profile, and, with increasing technology, higher pregnancy rates. We recommend progressing from "low-tech" procedures, such as IUI and reserving the higher level procedures, such as IVF and ICSI, for those couples in whom pregnancy does not occur. The highest level reproductive technologies give the best current prospects for pregnancy in patients with this difficult problem but also are invasive and costly. It is hoped that further work in the laboratory will give rise to newer, safer, and less expensive effective treatments in the very near future.

Immunology of the testicular excurrent ducts

The sperm autoantigen concentration in the epididymis equals or exceeds that in the testis. This makes the epididymis a probable site of initiation of an antisperm autoimmune response. The mechanisms regulating antisperm antibody formation in the testicular excurrent ducts and some related aspects with clinical interest are reviewed.

Correlation between epididymal length and fertilization rate in men with congenital absence of the vas deferens

OBJECTIVE

To investigate whether the variable length of the epididymides in men with congenital absence of the vas deferens might have a correlation with IVF and pregnancy rate results.

DESIGN

Microsurgical retrieval of epididymal sperm from men with congenital absence of the vas deferens and their use for IVF.

SETTING

Center for Reproductive Health, University of California, Irvine, California.

PATIENTS

One hundred eight men with confirmed diagnosis of congenital absence of the vas deferens enrolled in the microsurgical epididymal sperm aspiration and IVF program.

INTERVENTIONS

Measurement in centimeters of the epididymal length at the time of the sperm aspiration procedure.

MAIN OUTCOME MEASURE

Rates of fertilization and pregnancy according to the epididymal length.

RESULTS

Three groups were identified: group I (n = 29), epididymal length between 0.5 and 1.9 cm; group II (n = 66), length between 2.0 and 4.0 cm; and group III (n = 13), length in excess of 4.0 cm. Although the aspiration site was the proximal caput for each case, patients of group III had the highest fertilization and pregnancy rate (24% and 43%, respectively). Patients with the shortest epididymis (group I) had the worst IVF outcome (fertilization rate 7% and pregnancy rate 7%) whereas in group II the fertilization rate was 13% and the pregnancy rate was 18%.

CONCLUSION

This study demonstrates that epididymal sperm from men with congenital absence of the vas deferens having a longer epididymis have a better IVF rate. A long epididymis can allow [1] the arrival of more frequent waves of fresh sperm whereas in a short epididymis the system is completely congested and occupied by old and senescent sperm, [2] less obstructive damages, and [3] a back flow of biochemical factors produced in the more distal segments that could ultimately enhance the fertilization capacity of proximal epididymal sperm.

Sperm antibodies in a patient with obstructive azoospermia

An artificial spermatocoele was constructed at the level of the caput epididymis in a patient with obstructive azoospermia. Morphologically normal spermatozoa were harvested but motility and progression were inadequate for intra-uterine insemination or in vitro fertilisation. In addition, there was an antispermatozoal antibody response which transuded back into the reproductive tract and coated spermatozoa with antibody. It is recommended that if harvesting of epididymal spermatozoa is contemplated, the serum should initially be assessed for spermatozoal antibody.