Etiological implication of autoantibodies to zona pellucida in human female infertility

The Impact of Assisted Reproductive Technology on Umbilical Cord Insertion: Increased Risk of Velamentous Cord Insertion in Singleton Pregnancies Conceived through ICSI

Background and Objectives: Vasa previa (VP) is a significant perinatal complication that can have serious consequences for the fetus/neonate. Velamentous cord insertion (VCI) is a crucial finding in prenatal placental morphology surveillance as it is indicative of comorbid VP. Assisted reproductive technology (ART) has been identified as a risk factor for VCI, so identifying risk factors for VCI in ART could improve VP recognition. This study aims to evaluate the displacement of umbilical cord insertion (CI) from the placental center and to examine the relationship between the modes of conception. Materials and Methods: We conducted a retrospective study at the Obstetrics Department of Osaka Metropolitan University Hospital in Japan between May 2020 and June 2022. The study included a total of 1102 patients who delivered after 22 weeks of gestation. They were divided into three groups: spontaneous pregnancy, conventional in vitro fertilization (cIVF), and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). We recorded patient background information, perinatal complications, perinatal outcomes, and a numerical "displacement score", indicating the degree of separation between umbilical CI and the placental center. Results: The displacement score was significantly higher in the cIVF and IVF/ICSI groups compared with the spontaneous conception group. Additionally, the IVF/ICSI group showed a significantly higher displacement score than the cIVF group. Conclusions: Our study provides the first evidence that the methods of ART can affect the location of umbilical CI on the placental surface. Furthermore, we found that IVF/ICSI may contribute to greater displacement of CI from the placental center.

Premature ovarian insufficiency (POI) and autoimmunity-an update appraisal

PURPOSE

Primary ovarian insufficiency (POI) represents ovarian dysfunction related to very early aging of the ovaries. While the cause of POI in a majority of clinical cases remains undefined, autoimmunity is responsible for approximately 4-30% of POI cases. In the present paper, we aim to provide a critical appraisal and update review on the role of autoimmunity in POI patients.

METHODS

A literature review was conducted for all relevant articles reporting on POI and autoimmunity. PubMed/MEDLINE and the Cochrane library were searched for the best available evidence on this topic.

RESULTS

Patients with POI and coexisting autoimmunity are indistinguishable from those with negative autoimmune screen with regard to age of onset, prevalence of primary amenorrhea, or their endocrine profiles. A specific noninvasive reliable diagnostic test for the diagnosis of an autoimmune etiology is lacking; therefore, patients should be screened for the most common autoantibodies, i.e., steroid cell antibodies, anti-ovarian antibodies, and anti-thyroid antibodies. Moreover, treatment strategies to POI infertility are lacking and controversial.

CONCLUSIONS

Nowadays, guidelines for the treatment of autoimmune POI are not available. Moreover, since diagnostic and treatment strategies to POI infertility are still lacking and controversial, further large clinical studies are needed to investigate the true impact of autoimmunity on POI and to identify the selected groups of patients who are most likely to benefit from immunossuprresive treatment.

Infertility and Immunocontraception based on zona pellucida

The zona pellucida (ZP) is an extracellular matrix surrounding ovarian oocytes, ovulated eggs and preimplantation embryos. It plays several important roles at different stages of reproduction. Its constituent glycoproteins are expressed specifically in the ovary. It is thus possible to produce autoantibodies to ZP proteins that interfere with reproductive functions including folliculogenesis, fertilization and implantation. First, this article describes the history of anti-ZP antibodies detected in women with idiopathic infertility. Second, the current relationship between anti-ZP antibodies and infertility is discussed in relation to assisted reproductive medicine. Third, we introduce the latest studies of animal experiments involving the ZP. Finally, immunocontraceptive vaccine development using various ZP antigens is reviewed.

Multiplicity of molecular and cellular targets in human ovarian autoimmunity: an update

PURPOSE

To provide an update of putative auto-antigens identified and proposed to be involved in human ovarian autoimmunity.

METHODS

Review of literature pertaining to ovarian auto-antigens / proteins identified with various immunological tools using sera of infertile women as a probe for investigation.

RESULTS

An overview of autoimmune targets known till date in the study of human ovarian autoimmunity.

CONCLUSIONS

Anti-ovarian antibodies (AOA) to multiple components and compartments of the ovary are present in the sera of infertile women. Researchers propose that these AOA may be responsible for ovarian failures and therefore render women to be infertile. Evaluation of AOA can be effective as a prognostic factor in the treatment of infertile patients and for the IVF-ET program.

Detection of antizona pellucida antibodies in the sera from premature ovarian failure patients by a highly specific test

OBJECTIVE

To develop a highly specific test for the detection of antizona pellucida (ZP) antibodies in the sera from premature ovarian failure (POF) patients.

DESIGN

Laboratory study.

SETTING

University hospital.

PATIENT(S)

Twenty-seven idiopathic POF patients, 30 control women, and 30 healthy males.

INTERVENTION(S)

Anti-ZP antibodies were detected by the microdot assay using a very small amount of human ZP or porcine ZP. The effect of anti-ZP antibodies on sperm-ZP binding was examined by hemizona assay.

MAIN OUTCOME MEASURE(S)

Results from the microdot assay and hemizona assay.

RESULT(S)

By the microdot assay using human ZP, the sera from POF patients reacted significantly stronger than those of control women and healthy males. However, no obvious difference could be found by the same assay using porcine ZP among these three groups. Anti-ZP antibodies against sera from some POF patients showed significant blocking effects on sperm-ZP binding assessed by hemizona assay. Anti-ZP antibodies were detected in 7 of 27 POF patients, while none were detected in control women and healthy males.

CONCLUSION(S)

Some idiopathic POF patients have anti-ZP antibodies in their sera, which were detected with high specificity by a newly developed microdot assay using a very small amount of human ZP.

Antiovarian antibodies in primary Sjogren's syndrome

Our study aimed at screening patients with primary Sjogren's syndrome (pSs) for the presence of antiovarian antibodies (AOAs). Detection of AOAs in patients' sera was achieved by ELISA, using bovine ovarian extract for coating. Western blot analysis and immunohistochemistry were used to characterize the antibody targets in the extract and to determine their locus on the bovine ovary, respectively. Specific AOAs were detected in 27% of 37 patients (two with premature menopause) and in none of the controls. Immunoreactivity mainly resided in five proteins of the extract with molecular masses 42, 49, 55, 64 and 72 kDa, and it might be attributed to their carbohydrate components. The antibody targets were mainly located in the granulosa and theca interna cells of the follicle, and in the endothelial cells and fibroblasts of corpus luteum. The detection, for the first time, of AOAs in a significant percentage of patients with pSs may suggest autoimmune oophoritis, clinical or subclinical.

Alpha-enolase: a novel autoantigen in patients with premature ovarian failure

OBJECTIVE

Although controversial, the presence of circulating antiovarian antibodies (AOA) may be considered a marker of autoimmune premature ovarian failure (POF). The purpose of the present work was to evaluate the presence of AOA in POF patients, and to identify a possible autoantigen in order to develop a reliable diagnostic tool that might help to determine the real prevalence of autoimmune POF.

DESIGN

Non-randomised study. Blood sampling for determination of circulating AOA.

PATIENTS

One hundred and ten patients with POF and 60 normally menstruating women with no record of autoimmune diseases (controls).

MEASUREMENTS

Presence of circulating AOA was assessed by Western-blot, using cytosolic fraction from human ovarian homogenate as antigen.

RESULTS

Twenty-one of 110 women with POF presented circulating antibodies directed toward an antigen of approximately 50 kD. Sixty control subjects proved negative. After purification and analysis by mass spectrometry, the antigen was identified as alpha-enolase.

CONCLUSION

Determination of the presence of circulating antialpha-enolase antibodies might be instrumental in identifying those patients who may present a putative defect in immunoregulation and therefore a possible autoimmune aetiolgy for POF.

Autoimmune targeted disruption of the pituitary-ovarian axis causes premature ovarian failure

Premature ovarian failure (POF) is characterized by amenorrhea and high serum levels of follicle-stimulating hormone (FSH). POF causes female infertility and represents a substantial women's health risk affecting 1% of women by age 40. Although ovarian autoimmunity has been associated with POF, the identity of ovarian Ags recognized is unknown. In this study, we show that autoimmune-targeted disruption of the pituitary-ovarian axis leads to POF. Immunization of SWXJ female mice with the p215-234 peptide derived from mouse inhibin-alpha activates CD4(+) T cells and induces experimental autoimmune oophoritis with a unique biphasic phenotype characterized by an early stage of enhanced fertility followed by a delayed stage of POF. Affected mice show high serum levels of inhibin-alpha-neutralizing Abs that prevent inhibin-mediated down-regulation of activin-induced pituitary FSH release. The loss of activin/FSH down-regulation leads to prolonged metestrus-diestrus, superovulation, increased numbers of mature follicles, increased offspring, accelerated depletion of primordial follicles, and ultimately premature infertility. Thus, inhibin-alpha-targeted experimental autoimmune oophoritis is initiated by CD4(+) Th1 T cells that stimulate B cells to produce inhibin-alpha-neutralizing Abs directly capable of mediating POF and transferring disease into naive recipients. Our inhibin-alpha autoimmune model of POF shows how premature infertility may develop in the context of elevated FSH levels thereby closely mimicking the hallmark features of human POF.

Sperm-zona pellucida interaction and immunological infertility

Immune reactions against gametes appear to be physiologically important for the maintenance of homeostasis in reproduction. In contrast, aberration of the immune homeostasis might give rise to 'immunological infertility'. Antisperm antibodies cause infertility by blocking fertilization. The mechanism can be explained as inhibiting the acrosome reaction of sperm by their blocking effect on capacitation through inhibiting an increase of fluidity of the sperm membrane. Autoantibodies against zona pellucida also cause infertility by blocking sperm-zona pellucida interaction, though the definitive mechanism has not been elucidated. Pretreatment of spermatozoa with D-mannnose completely inhibited sperm penetration through, but not binding to, the zona pellucida. Furthermore, very rapid kinetics between sperm extracts and D-mannnose by a BIAcore apparatus suggest that a D-mannose ligand of the sperm surface is easy to bind to and dissociate from a D-mannose residue in the sperm receptor site on the zona pellucida. Thus, D-mannnose on the human zona pellucida might be an essential molecule acting as a second sperm receptor, through which sperm penetrate into the zona pellucida. Because these antibodies appear to not cause any deleterious clinical symptoms, sperm and zona pellucida antigens are promising candidates in the development of an immunocontraceptive. (Reprod Med Biol 2006; 5: 95-104).

Sperm-zona pellucida interaction and immunological infertility

Immune reactions against gametes appear to be physiologically important for the maintenance of homeostasis in reproduction. In contrast, aberration of the immune homeostasis might give rise to 'immunological infertility'. Antisperm antibodies cause infertility by blocking fertilization. The mechanism can be explained as inhibiting the acrosome reaction of sperm by their blocking effect on capacitation through inhibiting an increase of fluidity of the sperm membrane. Autoantibodies against zona pellucida also cause infertility by blocking sperm-zona pellucida interaction, though the definitive mechanism has not been elucidated. Pretreatment of spermatozoa with D-mannnose completely inhibited sperm penetration through, but not binding to, the zona pellucida. Furthermore, very rapid kinetics between sperm extracts and D-mannnose by a BIAcore apparatus suggest that a D-mannose ligand of the sperm surface is easy to bind to and dissociate from a D-mannose residue in the sperm receptor site on the zona pellucida. Thus, D-mannnose on the human zona pellucida might be an essential molecule acting as a second sperm receptor, through which sperm penetrate into the zona pellucida. Because these antibodies appear to not cause any deleterious clinical symptoms, sperm and zona pellucida antigens are promising candidates in the development of an immunocontraceptive. (Reprod Med Biol 2006; 5: 95-104).

[Ovarian autoimmunity and ovarian pathologies: antigenic targets and diagnostic significance]

The involvement of serum anti-ovarian autoantibodies (AOA) in ovarian pathology still remains controversial. In some cases of clinically patent ovarian failure, there seems to be a causal relationship between AOA and the ovarian disease. In patients with various organ-specific or systemic autoimmune diseases, or with unexplained, repeated reproductive failure, but otherwise normal ovarian function, it is even more difficult to determine the significance of AOA for several reasons: i) AOA recognize many different antigenic targets in the ovary ii) the antiovarian response may be transient or variable with time iii) the presence of AOA does not imply their aetiopathogenic role in the disease. The present paper reviews the clinical significance of AOA based on their ovarian targets as far as they have been identified until now.

Fimbrio-Ovarian Relationship in Unexplained Infertility

INTRODUCTION

The role of defective fimbrio-ovarian relation in cases of unexplained infertility has not been extensively studied. The aim of the study was to assess the role of fimbrio-ovarian relation as an investigative modality in women with unexplained infertility. We also aimed to evaluate the efficacy of superovulation and freeing the fimbria-ovarica in increasing the conception rate of women with unexplained infertility.

MATERIALS AND METHODS

This was a prospective study where out of 80 infertile couples, 19 women with unexplained infertility were recruited as study group. Fifteen fertile women were recruited as control group. During laparoscopy the length of the fimbria-ovarica and the ovulation border was measured. The fimbrio-ovarian accessibility test was demonstrated by holding the tubal fimbria by a non-traumatizing grasper and their ability to reach or cover the ovulation site. The freeing of the fimbria-ovarica was done, if its length was less than 2 cm. All cases were given ovulation induction for consecutive six cycles and were followed up to document any conception.

RESULTS

The mean length of the fimbria-ovarica was significantly less in patients with unexplained infertility (2.5 +/- 0.6 vs. 3.55 +/- 0.8 cm). The mean length of the ovulation border was not significantly different in cases and controls (2.95 +/- 0.6 vs. 3.55 +/- 0.5 cm). The fimbrio-ovarian accessibility test was positive in 6 (31.5%) cases and in 14 (93%) controls. The fimbrio-ovarian accessibility test was negative in 13 (68.4%) cases and in 1 (7%) control. Out of the 13 cases with negative FOAT, 7 had fimbrial length less than 2 cm and in whom the freeing of fimbria-ovarica was done because of severe resistance during stretching. Out of 7 patients in whom freeing of fimbria-ovarica was done 3 conceived (42.8%). Out of the 12 patients who got only ovulation induction 3 conceived (25%).

CONCLUSION

Fimbrio-ovarian accessibility test appears to be a promising investigative modality to assess ovarian pick-up in patients with unexplained infertility. Correcting fimbrio-ovarian relation (freeing short fimbria-ovarica) improves pregnancy rate in women with unexplained infertility.

Gonadal antibodies interfering with female reproduction

While the involvement of anti-ovarian antibodies (AOAs) is highly likely, yet still controversial, in patients with patent premature ovarian failure (POF), it is even more difficult--for several reasons--to ascertain the clinical significance of these antibodies in patients without obvious ovarian failure. First, AOAs form a heterogeneous group of antibodies recognizing several different antigenic targets such as granulosa and thecal cells, zona pellucida, oocyte cytoplasm, corpus luteum, as well as gonadotrophins and their receptors. Second, the detection of AOAs in various clinical situations does not readily imply a causal relationship between these antibodies and impaired ovarian function. Third, diagnostic tools for detecting AOAs and their molecular targets have to be improved to yield more reliable data and allow a better comprehension of the pathophysiology of AOAs. Preliminary results with immunosuppressive therapy in selected AOA patients have been encouraging, but randomized trials have to be performed.

[What are the antigenic targets in the ovary?]

The ovary can be the target of an autoimmune disease involving many different autoantigens. The clinical feature of this disease often results in premature ovarian failure or infertility and may be either isolated or associated with other autoimmune pathologies, especially with adrenal autoimmunity. The diagnosis of an autoimmune mechanism relies on the presence of anti-ovarian antibodies, whose prevalence is quite variable according to the different methods used to detect them, and to the different stages of the disease. In addition, their clinical significance is not always clear, as to their pathologic or epiphenomenal nature. However, the study of these autoantibodies has led to the identification of some of their antigenic targets which have to be known for a better understanding of the pathologic mechanisms involved. This paper reviews anti-steroid producing cells, anti-gonadotrophin receptor, anti-gonadotrophin, anti-corpus luteum, anti-zona pellucida and anti-oocyte antibodies.

Ovarian autoimmune disease and ovarian autoantibodies

Detection of specific autoantibodies remains the most practical clinical and research marker of autoimmune disease. The lack of consensus on ovary specific antibodies as a marker for ovarian autoimmunity has clinical and research consequences. The objective of this review is to summarize the evidence for ovarian autoimmunity and the detection of ovary specific autoantibodies in humans. Evidence favors the presence of an autoimmune disease of the ovary. Ovarian autoantibodies are associated primarily with premature ovarian failure (POF) and unexplained infertility. Variations in detection of ovarian autoantibodies are likely to be due to study design elements such as antibody test format, antigen preparation, and criteria for study and comparison groups. In addition, multiple targets appear to be involved in ovarian autoimmunity including ovarian cellular elements and oocyte related antigens. Many studies only assess one target antigen, leaving individuals with ovarian autoimmunity unidentified. The next most significant advance in characterizing ovarian autoimmunity will be definitive identification of the specific antigens and development of standardized tests based on use of specific antigens.

Antizona and antisperm antibodies in women with endometriosis and/or infertility

OBJECTIVE

To measure the levels of antigamete antibodies in serum and peritoneal fluid of women with endometriosis and/or infertility.

DESIGN

Antibody activity against human sperm and porcine oocytes was analyzed in selected subgroups of women.

SETTING

Clinic of reproduction.

PATIENT(S)

Women with endometriosis and/or infertility.

INTERVENTION(S)

No treatment was implemented before peritoneal fluid and blood sample collection.

MAIN OUTCOME MEASURE(S)

Quantitative ELISA.

RESULT(S)

Four groups of women (n = 98) were analyzed for the presence of antizona and antisperm antibodies: infertile with endometriosis (n = 30), idiopathic infertility (n = 28), fertile with endometriosis (n = 20), and healthy fertile controls (n = 20). Antibodies were analyzed simultaneously in serum and peritoneal fluid. No statistically significant differences in antibody levels were detected in serum samples among the analyzed groups. The median values for antizona and antisperm antibodies in peritoneal fluid were significantly higher in women with idiopathic infertility than in the control group. In women with unexplained infertility, a high degree of correlation (Spearman) was found between the presence of antizona antibodies in peritoneal fluid and serum (r = 0.579). A positive predictive value of 80% was calculated for the presence of antizona antibodies (>5 ng/oocyte) in the peritoneal fluid of patients with infertility.

CONCLUSION(S)

Antizona antibodies locally produced in the peritoneal fluid have diagnostic value for infertility status; however, they cannot be treated as a marker or prognostic factor for minimal endometriosis and/or its treatment.

Immunization of chickens with quail and turkey perivitelline membrane proteins: production of antibodies and their effects on fertility

The cross-reactivity of antibodies developed against zona pellucida proteins and their subsequent deleterious effect on fertility in heterologous species is well documented. However, similar investigations have not been undertaken in avian species. In Experiment 1, White Leghorn hens were immunized with intact germinal discs (GD) of quail and chickens. Chicken GD proteins did not elicit an immune response in chicken hens, whereas quail GD proteins were highly immunogenic. Anti-quail GD antibodies did not bind with chicken inner perivitelline membrane (IPM) proteins as determined by immunoblot analysis. To examine the fertility of immunized hens, artificial insemination was performed at weekly intervals for 4 wk following the booster immunization. No significant differences were detected in fertility or hatchability of immunized hens when compared with unimmunized control hens. In Experiment 2, White Leghorn hens were immunized with intact turkey GD, solubilized turkey perivitelline membrane (PM) modified with dinitrophenol (DNP), and solubilized chicken IPM modified with DNP. High titers of antibodies were detected against the turkey GD and the DNP-modified turkey PM proteins. A weak immune response was observed in hens immunized with modified chicken IPM proteins. The fertility and hatchability of eggs laid by immunized hens, however, were not significantly different from those of unimmunized hens. Antibodies from immunized hens were further analyzed using an in vitro assay that assesses sperm penetration of intact IPM. Sperm penetration of intact IPM was inhibited to the same extent when IPM was preincubated with preimmune as well as anti-PM immunoglobulins. Collectively, these results suggested that the antibodies developed in these hens did not cross-react with the chicken IPM proteins involved in sperm-egg interaction and thus did not influence the fertility.

Quality of embryo does not affect the implantation rate of IVF-ET in infertile women with antisperm antibody

OBJECTIVE

To determine whether low quality score of embryos and advanced maternal age affect the implantation rate in infertile women with sperm-immobilizing antibody.

DESIGN

A retrospective study.

SETTING

The IVF Unit of the Department of Obstetrics and Gynecology at Tokushima University Hospital.

PATIENT(S)

Four infertile groups were studied: 20 women with sperm-immobilizing antibodies; 169 with tubal; 129 with male factor; and 72 with unexplained etiology.

INTERVENTION(S)

All women were hyperstimulated with GnRH analogue and scheduled ovarian stimulation with FSH and hMG for oocyte retrieval.

MAIN OUTCOME MEASURE(S)

Relationship of quality of transferred embryos, implantation rate and maternal age among four groups of infertile couples.

RESULT(S)

In the antisperm group, the fertilization rate (57.6%) and mean (+/- SD) score of transferred embryos (5.4+/-1.9) were significantly lower than those in the tubal group (72.4% and 6.2+/-1.9, respectively). However, the implantation rate in the antisperm group (23.6%) was significantly higher than those in other three groups (tubal, 8.6%; male factor, 9.5%; unexplained, 7.6%). With advancing maternal age, the implantation rate decreased in the three comparative groups. In contrast, the implantation rate in the antisperm group did not decrease with advancing maternal age.

CONCLUSION(S)

Women with antisperm antibodies have several disadvantages to overcome in order to achieve successful IVF-ET, such as a low fertilization rate and poor quality of transferred embryos. However, a high implantation rate was observed in this group, even in women at advanced age. The occurrence of a cellular or humoral immune reaction against sperm may augment the uterine receptivity for the implantation of fertilized ova or blastocyst.

Semen analysis and antisperm antibody

Evaluation of the fertilizing potential of sperm is an important procedure in in vitro fertilization and embryo transfer (IVF-ET) clinic, in order to avoid performing invalid conventional IVF-ET or unnecessary intracytoplasmic sperm injection (ICSI). However, none of the standard semen parameters are reliable indices in predicting IVF outcome. The test examining sperm-zona interaction is the best present method, though the short supply of the human zona component should be solved. IVF-ET treatment is useful for pregnancy in women having sperm immobilizing antibodies because it avoids exposing sperms to antibodies that block fertilization. ICSI should be used in immunologically infertile men diagnosed by specific method to demonstrate the in vivo exposure of sperms to antisperm autoantibodies that block fertilization.

Autoantibodies and infertility: a review of the literature

The role that autoantibodies play in infertility remains uncertain. There are conflicting data regarding the prevalence of autoantibodies in women with endometriosis. Certainly no one has demonstrated an association between the presence of antibodies in women with endometriosis and infertility. Despite intensive study, there is also no consensus on a role of autoantibodies to the zona pellucida as a cause of infertility. Recently, much attention has been focused on autoantibodies and infertility particularly with regards to phospholipid antibodies and their effect on IVF success rates. The literature suggests that women with infertility have an increased prevalence of phospholipid antibodies compared to fertile women. However, the presence of these antibodies has not been associated with a worsened prognosis for IVF cycles. Many questions remain to be answered. What is the cause of this apparently increased prevalence of autoantibodies in infertile women? Do these autoantibodies cause infertility or are they merely associated with some other condition which is actually causitive? Finally, can treatment of autoantibodies improve pregnancy rates in infertile couples after IVF or other infertility treatments? The answers to these questions should be sought by carefully conducted trials with appropriate control groups. Subjecting patients to expensive testing and 'treatments' before these answers are known is not consistent with good scientific or medical practice.

Premature ovarian failure and ovarian autoimmunity

Premature ovarian failure (POF) is defined as a syndrome characterized by menopause before the age of 40 yr. The patients suffer from anovulation and hypoestrogenism. Approximately 1% of women will experience menopause before the age of 40 yr. POF is a heterogeneous disorder with a multicausal pathogenesis involving chromosomal, genetic, enzymatic, infectious, and iatrogenic causes. There remains, however, a group of POF patients without a known etiology, the so-called "idiopathic" form. An autoimmune etiology is hypothesized for the POF cases with a concomitant Addison's disease and/or oöphoritis. It is concluded in this review that POF in association with adrenal autoimmunity and/or Addison's disease (2-10% of the idiopathic POF patients) is indeed an autoimmune disease. The following evidence warrants this view: 1) The presence of autoantibodies to steroid-producing cells in these patients; 2) The characterization of shared autoantigens between adrenal and ovarian steroid-producing cells; 3) The histological picture of the ovaries of such cases (lymphoplasmacellular infiltrate around steroid-producing cells); 4) The existence of various autoimmune animal models for this syndrome, which underlines the autoimmune nature of the disease. There is some circumstantial evidence for an autoimmune pathogenesis in idiopathic POF patients in the absence of adrenal autoimmunity or Addison's disease. Arguments in support of this are: 1) The presence of cellular immune abnormalities in this POF patient group reminiscent of endocrine autoimmune diseases such as IDDM, Graves' disease, and Addison's disease; 2) The more than normal association with IDDM and myasthenia gravis. Data on the presence of various ovarian autoantibodies and anti-receptor antibodies in these patients are, however, inconclusive and need further evaluation. A strong argument against an autoimmune pathogenesis of POF in these patients is the nearly absent histological confirmation (the presence of an oöphoritis) in these cases (< 3%). However, in animal models using ZP immunization, similar follicular depletion and fibrosis (as in the POF women) can be detected. Accepting the concept that POF is a heterogenous disorder in which some of the idiopathic forms are based on an abnormal self-recognition by the immune system will lead to new approaches in the treatment of infertility of these patients. There are already a few reports on a successful ovulation-inducing treatment of selected POF patients (those with other autoimmune phenomena) with immunomodulating therapies, such as high dosages of corticosteroids (288-292).

Human autoantibodies recognizing human and mouse preimplantation stages

PROBLEM

To find out whether autoantibodies against human preimplantation stages are present in some human sera and, if so, whether the antibodies could be capable to affect the egg development and/or to trigger an activation of the complement system at the procedures of assisted conception.

METHODS

1. Immunohistochemistry on blots of human preimplantation stages. 2. Immunohistochemistry on paraffin sections of human and mouse preimplantation stages. 3. Culture of mouse morulae to analyze complement activation.

RESULTS

1. Some human sera contained autoantibodies against human preimplantation stages. 2. Human-mouse cross-reacting antibodies against preimplantation stages occurred. 3. Immune complexes, formed on mouse preimplantation stages, activated the complement systems in egg cultures, resulting in a damaging of the eggs.

CONCLUSION

The presence of natural autoantibodies to preimplantation stages may be associated with reproduction failure, caused by a direct effect by the autoantibodies and/or an activation of the uterine complement system by the immune complexes formed.

High implantation rate and consequently high pregnancy rate by in vitro fertilization-embryo transfer treatment in infertile women with antisperm antibody

OBJECTIVE

To examine the effect of antisperm immunity on postfertilization steps, such as implantation of embryos and fetal growth in IVF-ET treatment of women with sperm-immobilizing antibodies.

DESIGN

Retrospective analysis of clinical laboratory data.

SETTING

The IVF-ET program of the Department of Obstetrics and Gynecology. The University of Tokushima, School of Medicine.

PATIENTS

Eighteen women with sperm-immobilizing antibodies and 122 infertile patients with nonimmune etiology as controls. Infertile couples due to a male factor and with unknown etiology were excluded.

INTERVENTIONS

All patients received the same IVF-ET program with GnRH agonist.

MAIN OUTCOME MEASURES

Rates of fertilization and cleavage, implantation rate per embryo transferred and pregnancy rate (PR) in both test and comparison groups.

RESULTS

The rate of fertilization in the antisperm group (61.3%) was significantly lower than that in the comparison group (76.8%). But the implantation rate per embryo transferred (23.5%) and consequently the modified PR per oocyte recovery procedure (34.4%) in immunologically infertile women were significantly higher than those in the comparison group (7.9% and 17.8%, respectively).

CONCLUSIONS

Although sperm-immobilizing antibodies prevent sperm-egg interaction, they do not seem to have any adverse effects on achievement of pregnancy. Moreover, the existence of antisperm immunity in woman with antisperm antibodies is suggested to be favorable for successful pregnancy by the IVF-ET procedure.