Intracytoplasmic sperm injection for treating infertility associated with sperm autoimmunity

Emerging arguments for reproductive technologies in wildlife and their implications for assisted reproduction and conservation of threatened marsupials

Assisted reproductive technologies (ARTs) have significant potential to make a meaningful contribution to the conservation of threatened wildlife. This is true of Australia's iconic, and endangered koala (Phascolarctos cinereus). If developed, ARTs could offer a solution to manage genetic diversity and costs in breeding programs and may provide frozen repositories for either insurance or the practical production of genetically resilient koalas for release and on-ground recovery. Holding back the wider use of ARTs for koalas and other wildlife is a lack of funding to close the remaining knowledge gaps in the marsupial reproductive sciences and develop the reproductive tools needed. This lack of funding is arguably driven by a poor understanding of the potential contribution ARTs could make to threatened species management. We present a review of our cross-disciplinary and accessible strategy to draw much needed public attention and funding for the development of ARTs in wildlife, using emerging cost and genetic modelling arguments and the koala as a case study.

Latheef S, Sharun K, Khurana SK, K. A, Tiwari R, Bhatt P, K. V, Chaicumpa W. Role of Antisperm Antibodies in Infertility, Pregnancy, and Potential forContraceptive and Antifertility Vaccine Designs: Research Progress and Pioneering Vision

Sperm of humans, non-human primates, and other mammalian subjects is considered to be antigenic. The effect of changes in autoimmunity on reproductive cells such as spermatozoa and oocytes play a critical but indistinct role in fertility. Antisperm antibodies (ASAs) are invariably present in both females and males. However, the degree of ASA occurrence may vary according to individual and gender. Although the extent of infertility due to ASAs alone is yet to be determined, it has been found in almost 9-12% of patients who are infertile due to different causes. Postcoital presence of spermatozoa in the reproductive tract of women is not a contributory factor in ASA generation. However, ASA generation may be induced by trauma to the vaginal mucosa, or by anal or oral sex resulting in the deposition of sperm inside the digestive tract. It is strongly believed that, in humans and other species, at least some antibodies may bind to sperm antigens, causing infertility. This form of infertility is termed as immunological infertility, which may be accompanied by impairment of fertility, even in individuals with normozoospermia. Researchers target ASAs for two major reasons: (i) to elucidate the association between ASAs and infertility, the reason ASAs causes infertility, and the mechanism underlying ASA-mediated infertility; and (ii) to assess the potential of ASAs as a contraceptive in humans in case ASAs influences infertility. Therefore, this review explores the potential application of ASAs in the development of anti-spermatozoa vaccines for contraceptive purposes. The usefulness of ASAs for diagnosing obstructive azoospermia, salpingitis, and oligoasthenoteratozoospermia has been reviewed extensively. Important patents pertaining to potential candidates for spermatozoa-derived vaccines that may be utilized as contraceptives are discussed in depth. Antifertility vaccines, as well as treatments for ASA-related infertility, are also highlighted. This review will address many unresolved issues regarding mechanisms involving ASAs in the diagnosis, as well as prognoses, of male infertility. More documented scientific reports are cited to support the mechanisms underlying the potential role of ASA in infertility. The usefulness of sperm antigens or ASAs (recombinant) in human and wild or captive animal contraceptive vaccines has been revealed through research but is yet to be validated via clinical testing.

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.

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.

Intracytoplasmic injection of spermatozoa and spermatogenic cells: its biology and applications in humans and animals

Intracytoplasmic sperm injection (ICSI) has become the method of choice to overcome male infertility when all other forms of assisted fertilization have failed. Animals in which ICSI has produced normal offspring include many species. Success rate with normal spermatozoa is well above 50% in the mouse but ICSI success rates in other animals have been low, ranging from 0.3 to 16.5%. Mouse ICSI revealed that spermatozoa that cannot participate in normal fertilization can produce normal offspring by ICSI, provided their nuclei are genomically intact. Human ICSI using infertile spermatozoa has been highly successful perhaps because of the intrinsic instability of human sperm plasma membrane. The health of children born after ICSI and other assisted fertilization techniques is of major concern. Careful analyses suggest that higher incidences of congenital malformations and/or low birth weights after assisted fertilization are largely attributable to parental genetic background and increased incidence of multiple births, rather than to the techniques of assisted fertilization. Since the physiological and nutritional environments of developing embryos may cause persisting alteration in DNA methylation, extreme caution must be exercised in handling gametes and embryos in vitro. In the mouse, round spermatid injection (ROSI) has been routinely successful but its use in humans is controversial. Whether human ROSI and assisted fertilization involving younger spermatogenic cells are medically safe must be the subject of further investigations.

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.

Immune testing in fertility practice: truth or deception?

PURPOSE OF REVIEW

Much attention has been paid to the role of immunology in reproductive success or failure. Every step in the establishment of normal pregnancy has been implicated as a possible site of immune-mediated reproductive failure. The widespread testing of antiphospholipid, antinuclear, antithyroid, and antisperm antibodies, as well as generalized immune testing, have thus been employed to diagnose patients with otherwise unexplained infertility or recurrent pregnancy loss. Controversial data surrounding the widespread and variable use of immune testing in current fertility practice is reviewed to determine which tests are warranted based on sound scientific evidence. Because it is postulated that early miscarriage, when occult, could represent a failure of embryo implantation indistinguishable from unexplained infertility, this analysis of immune testing includes a discussion of patients with recurrent pregnancy loss.

RECENT FINDINGS

Despite the increased prevalence of abnormal immune testing associated with early reproductive failure, the most rigorous studies have not proven a cause and effect between these phenomena. There is wide variation and inconsistency regarding this association, depending upon which test(s) are employed, the study methodology used, and the patient population under study. The significance of selected immunological test abnormalities associated with early reproductive failure is uncertain.

SUMMARY

Great variability exists in identifying candidates for immune testing, determining which tests to order, interpreting the test results, and offering immunologic treatments. This review argues that the use of widespread immune testing in clinical practice can not be supported by existing data. The resulting therapies are similarly of unconfirmed benefit and may cause harm.

Comprehensive office evaluation in the new millennium

The success of a comprehensive office-based evaluation of male-factor infertility depends on the physician's thorough understanding of risk assessment in the history, identification of pertinent physical examination findings, and correct assessment of laboratory data. Office-based ultrasonographic techniques have already increased the urologist's ability to visualize suspected anatomic abnormalities, and the use of functional tests of sperm has given greater depth to the limited, but essential, prognostic capabilities of the routine semen analysis.

Basis, diagnosis and treatment of immunological infertility in men

Sperm-reactive antibodies (SpAb) are found attached to sperm, or present in serum or seminal fluid, in approximately 6% of men presenting with infertility. Data supports their pathophysiological role in some cases by the interference with sperm motility and/or sperm-egg interaction. The occurrence of SpAbs may follow disruption of either the cellular barrier separating sperm antigens from the immune system (e.g. testis trauma or obstruction to sperm outflow), or to dysregulation of normal immunosuppressive activities within the male reproductive tract. The epididymis is likely to be the key site of antibody generation, especially in the setting of obstruction. Detection methods are all based on the detection of Ig isotypes rather than specific antibody-antigen interactions, which limits their usefulness. Treatment options in the past (immunosuppression, intrauterine insemination, conventional in vitro fertilization) have been superceded by intracytoplasmic sperm injection (ICSI) which appears to circumvent all adverse effects of male SpAbs.

ICSI as an effective therapy for male factor with antisperm antibodies

This study was conducted to evaluate if in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI) is an effective treatment for infertility complicated by the presence in the male partner of sperm autoantibodies. Over a 1-year study period comparisons of fertilization, pregnancy, and implantation rates were made in couples where the male partner was negative or weakly positive for sperm autoantibodies (<50%) (gr 1); autoantibodies were strongly positive (>80%) (gr 2); or autoantibodies were moderately positive (50-80%) (gr 3). Only patients having oocytes fertilized by ICSI were included. The fertilization, clinical pregnancy, implantation, and miscarriage rate for group 1 (n = 67) was 56, 43, 21, and 14%. Comparable values for group 2 (n = 20) were 55, 40, 23, and 25%, and for group 3 (n = 6) were 63, 33, 23, and 0%. IVF with ICSI demonstrates comparable fertilization, pregnancy, implantation, and miscarriage rates in female partners of males with and without sperm autoantibodies.

Intracytoplasmic sperm injection increases embryo fragmentation without affecting clinical outcome

PURPOSE

To examine the effect of intracytoplasmic sperm injection (ICSI) on embryo fragmentation and implantation rates in those embryos chosen for transfer compared to conventional in vitro fertilization (IVF).

METHODS

We compared 253 infertility patients (71 ICSI and 182 IVF) with respect to age, semen analysis, number of embryos transferred, embryo fragmentation, implantation rate, and pregnancy rate. Embryo fragmentation was determined by one observer at the same laboratory over the entire study period.

RESULTS

A statistically significant difference was observed in mean embryo grade between IVF (2.2 +/- 0.84) and ICSI (2.5 +/- 0.77), P = 0.01. Additionally, the IVF patients had significantly more nonfragmented (grade I) embryos compared to the ICSI group, P < 0.01.

CONCLUSIONS

These data suggest that ICSI, irrespective of semen parameters, may increase embryo fragmentation and produce fewer nonfragmented grade I embryos while maintaining implantation and pregnancy rates similar to conventional IVF.

Comparison of human cervical mucus and artificial sperm penetration media

The cervical mucus penetration tests aid research and determine the clinical importance of positive sperm antibody tests. Limited availability and variability of human cervical mucus have instigated the search for mucus substitutes for these tests. This study compares sperm migration in cervical mucus with that in artificial media including hyaluronate solution, egg white and albumin Tyrode solution. Results were quantified by measuring the migration distance (the maximum distance of capillary migration from a semen reservoir by spermatozoa after 1 h) and the sperm concentration at half the migration distance. The mean of both measures for cervical mucus and hyaluronate solution were equivalent [4.4 +/- 1.1 (SD) versus 4.3 +/- 1.0 cm and 118 +/- 51 versus 111 +/- 44x10(3)/ml], and higher than in egg white and albumin Tyrode solution. Antisperm antibodies impaired sperm penetration in cervical mucus and hyaluronate solution in a similar manner (r = 0.92). These results suggest that hyaluronate solution sufficiently resembles human cervical mucus in terms of penetrability that it may be used as a substitute for mucus in capillary tube tests of sperm function. The higher penetrability of cervical mucus and hyaluronate solution is probably related to a channelling effect due to their polymeric structure.

Fertilization, embryo quality, and cryosurvival in in vitro fertilization and intracytoplasmic sperm injection cycles

PURPOSE

Our purpose was to investigate the influence of semen quality on fertilization, embryo morphology, cleavage, and cryosurvival in conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) programs.

METHODS

A retrospective analysis of 513 couples undergoing IVF and 255 couples undergoing ICSI was done.

RESULTS

Semen quality influenced fertilization in IVF and abnormal fertilization in IVF and ICSI, but no effects on the development, morphology, implantation capacity, or cryosurvival of embryos were found. Fertilization, embryo quality, and cryosurvival rates were similar after IVF and ICSI. The fertilization rate of mature oocytes in IVF was lower when cytoplasmic immaturity in the oocyte population was frequent. The speed of development of embryos was 2 hr faster after ICSI than after IVF. Two-cell-stage embryos survived best after cryopreservation with propanediol and sucrose on day 2.

CONCLUSIONS

After fertilization, semen parameters had no effect on the quality or cryosurvival of embryos in either IVF or ICSI.

Do autoantibodies to sperm reduce fecundity? A mini-review in historical perspective

PROBLEM

The paradox that early studies of antisperm antibodies in men showed a strong correlation between titers of circulating antibodies (essentially immunoglobulin [Ig] G) and reduction in conception rates, whereas more recent studies have indicated that the antifertility effect is mainly (or exclusively?) associated with IgA antibodies, impairing sperm migration through cervical mucus, was studied.

METHOD OF STUDY

Relevant literature focusing on antibodies on ejaculated sperm was analyzed.

RESULTS

Direct mixed antiglobulin reaction (MAR) and immunobead-binding tests are excellent and sensitive techniques for demonstrating antibodies of the IgG and IgA classes on sperm, and they have revealed that IgA antibodies are, with very rare exceptions, found only when IgG antibodies are also present. However, these tests tell little about the amounts of antibodies present, and attempts to measure quantitatively the amounts of Ig on sperm have indicated higher levels of IgA than IgG (despite the strongest MAR reactivities for IgG).

CONCLUSIONS

The patients with high levels of IgA to their sperm are mainly men with strong immune responses and, therefore, also high antibody titers in serum. Apparently, the locally produced IgA antibodies reach the sperm and occupy the binding sites before the main bulk of IgG reaches the seminal compartment with the prostatic fluid.

Influence of sperm surface antibodies on spontaneous pregnancy rates

OBJECTIVE

To determine the rates of spontaneous pregnancies among women whose infertile male partners had sperm surface antibodies.

DESIGN

Retrospective analysis.

SETTING

Infertility clinic of a university referral center.

PATIENT(S)

One hundred fifty-seven infertile couples; the male partner had IgA and/or IgG sperm surface antibody concentrations of >10%.

INTERVENTION

None.

MAIN OUTCOME MEASURE(S)

Spontaneous pregnancy rates (PRs) over 6 years.

RESULT(S)

Spontaneous PRs correlated negatively with antibody concentrations.

CONCLUSION(S)

Although the chance of spontaneous pregnancy among women whose partners had sperm antibody concentrations of <50% was good, intracytoplasmic sperm injection should be recommended to patients with concentrations of >90%.

Medical treatment for idiopathic male infertility: is it curative or palliative?

Medical treatment of disorders of sperm production and function remains an important goal despite major advances in assisted reproductive technology. Effective treatments exist for genital tract obstruction, gonadotrophin deficiency, sperm autoimmunity, coital disorders and some impairments caused by toxins or illness. However, the majority of men seen for reduced sperm production or function do not have these conditions and the empirical treatments used in the past are probably ineffective. New therapeutic approaches derived from research on the causes and mechanisms of testicular dysfunction are needed and their curative effects must be established by well-designed controlled clinical trials.