Relationship of sperm antibodies in women and men to human in vitro fertilization, cleavage, and pregnancy rate

Anti-sperm Antibodies as an Increasing Threat to Male Fertility: Immunological Insights, Diagnostic and Therapeutic Strategies

It is a fact that sperm possess antigenic properties. Substantial scientific research suggests that specific antibodies that attach to sperm antigens can induce infertility in both humans and other species. Antisperm antibodies (ASA) represent a significant etiology of infertility in humans, leading to immunoinfertility. The association between ASA and infertility is multifaceted. The observation of sperm agglutination, although not conclusive for the diagnosis of immunological infertility, may suggest the presence of ASA. Nevertheless, ASA may also manifest in the lack of any sperm agglutination. Managing ASA from an andrological perspective depends on the underlying cause and the specific approaches healthcare professionals adopt. The precise etiology of male infertility resulting from ASA remains unclear. Current research has examined the impact of ASA and its prevalence among infertile males to understand the relationship between ASA and changes in semen parameters. However, the findings have been inconclusive. Numerous techniques have been documented for the management of immunoinfertility. This review examines the importance of ASA in the context of infertility, encompassing the postulated mechanisms underlying the development of ASA, the various assays employed for detecting them, and the available treatments.

A novel protein biochip screening serum anti-sperm antibody expression and natural pregnancy rate in a follow-up study in Chinese infertility

Production of anti-sperm antibody (ASA) often suffers from autoimmune reaction against sperms in human infertility. The antibodies are measured in both blood and seminal plasma of males. Here, we reported a simple protein biochip methodology that takes advantage of a functionalized self-assembled monolayer modified by N-hydroxysuccinimide (NHS) and enables identification of anti-sperm antibody in Chinese male infertility. To validate this biochip platform, we immobilized purified sperm protein on the biochip surface and tested a variety of parameters in quality controls for the protein assay, respectively. Then, we analyzed serum samples from 368 patients with infertility and 116 healthy donors by means of this biochip simultaneously. We found that positive rate of serum ASA was 20.92% (77/368) in the cases and 1.72% (2/116) in the controls, respectively. Furthermore, we further corroborated the biochip assay in comparison with ELISA method. We found that both methods were compatible for the detection of serum ASA in the patients. In addition, a follow-up study for natural conception in ASA-positive and ASA-negative patients was conducted. The result showed a significant correlation between serum ASA expression and natural pregnancy rate 6.5% in ASA-positive patients while 18.9% in ASA-negative patients, indicating the potential roles of ASA in naturally reproductive processes.

Influence of antisperm antibodies in the semen on intracytoplasmic sperm injection outcome

OBJECTIVE

The aim of this study was to analyze the influence of autoantibodies against spermatozoa present in the semen on the outcome of in vitro fertilization with intracytoplasmic sperm injection (ICSI).

MATERIALS AND METHODS

We performed a retrospective analysis of clinical and laboratorial data from a six year-period ICSI cycles. Screening for the presence of ASA in the semen, by using the direct immunobeads test (IBT), was available for 351 cycles. According to the percentage of antibody-bound spermatozoa in the semen, we divided the cycles in four groups: I (n = 194): 0%-10% ASA; II (n = 107): 11%-20%; III (n = 33): 21%-50% and IV (n = 17): 51%-100% ASA. Additionally, a group of 349 ICSI cycles performed with ejaculated spermatozoa from oligo/asthenozoospermic men who had insufficient number of motile sperm available for ASA screening was included for comparison. ICSI outcomes were compared among groups and included fertilization rate (2 PN), cleavage rate, cleavage velocity, embryo quality, clinical pregnancy and miscarriage rates. Data were examined statistically, with an alpha level of 5% considered significant.

RESULTS

Fertilization, cleavage rate and velocity, percentage of good quality embryos, as well as clinical pregnancy and miscarriage rates did not differ among different ASA levels groups. ICSI outcomes in men exhibiting different levels of autoimmunity against spermatozoa did not differ from those with severely abnormal seminal parameters.

CONCLUSIONS

Our data indicate that intracytoplasmic sperm injection (ICSI) outcomes are not influenced by ASA levels on sperm.

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.

Contraceptive responses of female hamsters immunized with recombinant sperm protein P26h

BACKGROUND

A number of antigens have been characterized and proposed as potential candidates for immunocontraception. P26h, a 26-kDa hamster sperm protein located on the acrosomal cap, is known to be involved in sperm-zona pellucida interactions. Furthermore, in vivo fertilization can be blocked by active immunization of male hamsters against P26h or maltose-binding protein recombinant P26h (MBP-P26h).

OBJECTIVE

The aim of this study was to investigate the immune response and reproductive function of female hamsters immunized against MBP-P26h.

RESULTS

Active immunization against MBP-P26h resulted in anti-P26h circulating antibodies, with enzyme-linked immunosorbent assay (ELISA) titers showing interindividual variability. The antibodies produced by the animals immunized against MBP-P26h reacted with the native P26h protein in ELISA, in Western blot analysis and in immunostaining performed on cauda epididymal spermatozoa. Mating of immunized female hamsters resulted in a significant decrease in the number of viable fetuses only in females with high titers of anti-P26h circulating antibodies.

DISCUSSION

This result is in agreement with the sperm-zona pellucida binding assay's results. Indeed, sera collected from immunized animals, and not from control animals, significantly blocked sperm-zona pellucida binding in vitro. Histological studies showed that active immunization did not cause any pathology in the reproductive tissues.

CONCLUSION

These findings suggest that P26h is a potential candidate for the development of a contraceptive vaccine in both males and females.

Antisperm Antibodies in Semen, Sera and Follicular Fluids of Infertile Patients: Relation to Reproductive Outcome afterIn VitroFertilization

PROBLEM

Data given in the literature, regarding the influence of antisperm antibodies (ASA) in the semen and/or sera on in vitro fertilization (IVF) procedure outcome are controversial. The aim of this study was to compare the prevalence of ASA in semen, peripheral blood and follicular fluid as well as to determine total immunoglobulin concentration in the serum and follicular fluid. Selected parameters were analyzed with regard to IVF outcome.

METHOD OF STUDY

The study enrolled 52 married couples. ASA in the semen was determined by direct immunobead mixed antiglobulin reaction (MAR Screen test), while in the peripheral blood and follicular fluid was determined by indirect immunobead MAR Screen test. Immunoglobulin (IgG, IgM and IgA) concentration in the follicular fluid and serum was determined by a liquid-phase immunoprecipitation assay with nephelometric end-point detection and analyzed with regard to IVF outcome.

RESULTS

Semen MAR test IgG was < 20% in 38 couples, and > 20% in 14 couples. Fertilization (73.2% versus 71.5%) and pregnancy rates (28.9% versus 28.57%) in both groups of patients were not significantly different. The results of direct and indirect MAR test were not associated with fertilization and pregnancy rates. Total serum IgG, IgM and IgA in infertile women were within normal ranges. Follicular fluid IgG was within normal values for serum samples, while IgA and IgM were decreased.

CONCLUSION

The presence of ASA on sperm or in the serum and follicular fluid was not associated with IVF outcome in the couples with good quality semen characteristic.

Clinical associations and mechanisms of action of antisperm antibodies

OBJECTIVE

To review and critique the current English literature describing the effects of antisperm antibodies (ASA) on mammalian fertility.

DESIGN

A comprehensive English language literature was searched using Medline and by hand-searching. Emphasis was placed on clinically relevant articles.

RESULT(S)

Results from the studies were extrapolated and the effects of ASA on fertility described.

CONCLUSION(S)

Antisperm antibodies may interfere with fertility. Not all ASA cause infertility. Current tests cannot differentiate the infertility-related ASA from those that do not interfere with infertility, because the antigenic specificities of these ASA are not known. The antigens which the infertility-related ASA must be characterized to allow an accurate detection and proper treatment for couples with ASA.

Antisperm immunity in assisted reproduction

Antisperm antibodies (ASA) can impair the fertilising capacity of human spermatozoa, acting negatively on sperm motility and cervical mucus penetration, and at the level of in vitro gamete interaction. Several methods attempt to improve the potentially deleterious effects of ASA-mediated infertility: by decreasing ASA production, by removing ASA already bound to sperm, artificial insemination (AIH) and fertilisation (IVF, ICSI). Only ICSI seems able to overcome the problem, with fertilisation and pregnancy rates of ASA-positive patients undergoing this technique in the same range as ASA-negative patients. As immunological infertility is relatively rare, literature in the field is quite scarce and more studies need to be conducted to confirm that embryo quality is not impaired.

Minimal precycle testing and ongoing cycle monitoring for in vitro fertilization and fresh pre-embryo transfer do not compromise fertilization, implantation, or ongoing pregnancy rates

OBJECTIVE

We sought to assess the fertilization, implantation, and ongoing pregnancy rates with a minimal precycle and ongoing cycle monitoring protocol for in vitro fertilization and embryo transfer.

STUDY DESIGN

Retrospective review was conducted of 103 consecutive cycles of fresh in vitro fertilization and embryo transfer from 1996 to 1998. Precycle screening included semen analysis without strict morphologic analysis, and hysterosalpingography-sonohysterography within the last year. Serum prolactin, serum thyroid-stimulating hormone, reactive plasma reagin, human immunodeficiency virus, rubella titer, blood type, hepatitis B surface antigen, and hepatitis C antibody testing was performed on all patients within 3 months of cycle initiation. Women > or =37 years old underwent clomiphene challenge testing. The monitoring protocol included the following: baseline transvaginal ultrasonography after 12 to 14 days of midluteal gonadotropin-releasing hormone agonist down-regulation to assess endometrial thickness and adnexal appearance, transvaginal ultrasonography for follicle evaluation at 7 and 10 days, serum estradiol assay if > or =20 follicles, quantitative beta-human chorionic gonadotropin 12 to 14 days after pre-embryo transfer, repeat quantitative beta-human chorionic gonadotropin 3 to 5 days later, and transvaginal ultrasonography for intrauterine gestational sac confirmation 7 to 9 days after the initial positive pregnancy test result. The dose of gonadotropin used remained constant unless the sonogram obtained on day 7 indicated a suboptimal response (<3 follicles each, with an average diameter of 10 to 12 mm) or hyperresponse (> or =15 follicles with an average diameter of 10 to 12 mm).

RESULTS

The per embryo implantation rate (fetal cardiac activity) was 13.1%, and the live birth rate per 100 pre-embryo transfers was 31.5 for patients < or =40 years old. The average number of pre-embryos transferred was 3.1. The singleton pregnancy rate was 71%, and there were no multiple gestations greater than twins. The mean number of oocytes fertilized was 66%. There was 1 case of failed fertilization with intracytoplasmic sperm injection. There were two other cases of failed fertilization. One case of severe ovarian hyperstimulation occurred in spite of cryopreservation of all embryos.

CONCLUSIONS

In vitro fertilization and embryo transfer can be accomplished with minimal precycle testing and ongoing cycle monitoring without compromising fertilization, implantation, and ongoing pregnancy rates. This results in reduced overall costs for couples.

Significance of antisperm antibodies in female serum in a gamete intrafallopian transfer program

The influence of antisperm antibodies in the female serum on fertilization and pregnancy rate in patients undergoing GIFT was assessed. A study group of 52 couples (69 cycles) with significant levels of antisperm antibodies in the female serum were compared to a control group of 749 couples (1185 cycles). Maternal serum or donor serum was used as growth medium supplement. The TAT test was performed for the detection of antisperm antibodies in the serum. Antisperm-antibody presence in female serum was associated with similar fertilization and pregnancy rates in a GIFT program compared to the control group. The type of serum used as growth medium supplement did not affect statistically the fertilization or pregnancy rate.

Validity and cost-effectiveness of antisperm antibody testing before in vitro fertilization

OBJECTIVE

To determine the usefulness of and cost-effectiveness of antisperm antibody testing in the prediction of poor fertilization rates in couples undergoing IVF.

DESIGN

Retrospective cohort study.

SETTING

A hospital-based reproductive endocrinology and infertility practice.

PATIENT(S)

Male partners of 251 couples undergoing IVF between 1992 and 1997.

MAIN OUTCOME MEASURE(S)

Fertilization rates in couples undergoing conventional IVF.

RESULT(S)

One hundred nineteen couples were evaluated for antisperm antibodies; fertilization rates were similar in those couples whose husbands were and were not tested (64% versus 68%). Antisperm antibodies were detected in 16 men. Four (25%) of the 16 couples whose husbands had antisperm antibodies fertilized < or = 50% of oocytes, compared with 31 (30%) of the 103 couples whose husbands did not have these antibodies. Overall, 21 couples (8.4%) experienced complete fertilization failure. In a program that included antisperm antibody testing for selected couples and intracytoplasmic sperm injection (ICSI) for those who tested positive, it would cost $11,735 to prevent a fertilization failure (assuming ICSI were 100% effective), whereas it would cost $9,250 to perform ICSI in a second IVF cycle for those who initially failed.

CONCLUSION(S)

In this practice setting, antisperm antibody testing has low sensitivity in predicting low or no fertilization and does not appear to be cost-effective when selectively ordered as part of an IVF workup.

Antisperm antibodies: origin, regulation, and sperm reactivity in human infertility

OBJECTIVE

To follow-up and expand discussion on the action mechanisms of antisperm antibodies in human infertility, the etiology and control of antisperm antibody induction, sperm antigens involved in immunoinfertility, and strategies for therapy.

DESIGN

A review of the recent literature with an emphasis on female immunoinfertility.

RESULTS

The role of antisperm antibodies in clinical infertility continues to be defined. Through assisted reproductive technologies, antisperm antibodies were shown to exert detrimental effects on different prefertilization and possibly postfertilization events. The female reproductive tract is part of the common mucosal immune system and is able to mount effective immune responses against infectious agents, foreign antigens, and, occasionally, sperm cells. Sperm membranes and constituents contain numerous antigenic components foreign to the human body, and yet antisperm antibodies become problematic in few women exposed to semen. Semen and sperm cells contain immunosuppressive factors capable of inhibiting different immune cells. Fertile women apparently produce antisperm antibodies but also possess neutralizing serum anti-idiotypic antibodies that are lacking in virgin and immunoinfertile women.

CONCLUSIONS

Antisperm antibodies can affect adversely human fertility but normally may be controlled by anti-idiotypic antibodies, which along with immunosuppressor factors in semen prevent their induction to a significant degree. This balance between detrimental and "beneficial" immune response to sperm may be shifted toward an antisperm antibody response by stimulatory factors such as infection. Therapies may be devised to stimulate the anti-idiotypic antibody system, to induce immune tolerance to sperm antigens, and to use antigens to adsorb antisperm antibodies from spermatozoa.