Autoantibodies and common idiotypes in men and women with sperm antibodies

PD-1/PD-L and autoimmunity: A growing relationship

Programmed death 1 (PD-1) and its ligands, namely PD-L1 and PD-L2, are one of the key factors responsible for inhibitory T cell signaling, mediating the mechanisms of tolerance and providing immune homeostasis. Mounting evidence demonstrates that impaired PD-1:PD-L function plays an important role in a variety of autoimmune diseases such as Type 1 diabetes (T1D), encephalomyelitis, inflammatory bowel diseases (IBD), Rheumatoid Arthritis (RA), autoimmune hepatitis (AIH), Behcet's disease (BD), myasthenia gravis (MG), autoimmune uveitis (AU), Sjögren's syndrome (SjS), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), myocarditis, and ankylosing spondylitis (AS). By investigating the candidate genes, genome-wide association studies, and identification of single nucleotide polymorphisms (SNPs) in PD-1 gene in humans, it has been shown that there is a higher risk in relevant genetic associations with developing autoimmune diseases in certain ethnic groups. In this review we have tried to present a comprehensive role of PD-1:PD-L in all recently studied autoimmune diseases.

Association between a PD-1 gene polymorphism and antisperm antibody-related infertility in Iranian men

OBJECTIVE

Programmed cell death-1 (PD-1, Pdcd1), an immunoreceptor belonging to the CD28/CTLA-4 family negatively regulates antigen receptor signalling by recruiting protein tyrosine phosphatase, SHP-2 upon interacting with either of two ligands, PD-L1 or PD-L2. This study investigates PD-1 gene polymorphism in patients with antisperm antibody-related infertility

METHODS

Genotyping was performed by polymerase chain reaction and restriction enzyme digestion (PCR-RFLP), this polymorphism was genotyped in 145 Iranian subjects (61 patients with antisperm antibody-related infertility and 84 healthy controls).

RESULTS

Patients frequencies of the G/A genotype in comparison with healthy controls (38.2 % vs. 32.7 %, OR =1.21, P = 0.35) were not significantly different. However, G/G and A/A genotype frequencies between patients and healthy controls were significantly different (P = 0.042, P = 0.00001, respectively). Also, allele frequencies of this polymorphism were significantly different (P = 0.0012) in patients compared to healthy controls.

CONCLUSION

According to these results, there is a correlation between PD-1 gene polymorphism and susceptibility to antisperm antibody-related infertility in our study group.

Subclinical impairment of ovarian reserve in systemic lupus erythematosus patients with normal menstruation not using alkylating therapy

BACKGROUND

Disease activity is a major factor in menstrual disorders in systemic lupus erythematosus (SLE) patients not receiving alkylating therapy. However, the ovarian reserve of SLE women with normal menstruation is still unclear.

METHODS

Twenty-three SLE patients naïve to cytotoxic agents (SLE group) and nineteen SLE patients receiving current or previous cyclophosphamide (CTX) therapy (without other cytotoxic agents; SLE-CTX group) were enrolled. Twenty-one age-matched healthy women served as controls. All patients and controls had a regular menstrual cycle. Basal hormone levels, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and anti-Müllerian hormone (AMH), and antral follicle count (AFC) were analyzed in the two study groups and compared with the control group.

RESULTS

No significant differences were found between the SLE, SLE-CTX, and control groups in age, body mass index (BMI), and basal FSH and LH levels. The E2 (P=0.023) levels were high and the AMH (P=0.000) values and AFC (P=0.001) were significantly lower in the SLE and SLE-CTX groups compared to control. However, these values were similar between the SLE and SLE-CTX groups.

CONCLUSION

SLE patients not receiving alkylating therapy who had normal menstruation and short illness duration still had an impaired ovarian reserve.

Antisperm immunity and infertility

Immunoinfertility is one of several causes of infertility in humans. Although progress on antisperm immunity and infertility has advanced during the past three decades, the nature of a real antisperm antibody (ASA) is still poorly understood. Dozens of sperm antigens have been isolated and characterized in association with infertility. However, it is difficult to identify a single predominant target antigen that could interact with all the ASAs. There are some protective mechanisms preventing ASA production in males and females. As chronic infection, vasectomy and vasovasostomy, heavy metals, and testicular cancer and torsion may induce the production of ASAs, they may be responsible for decreased motility and sperm penetration of cervical mucus, and the blockage of the acrosome reaction and the sperm-egg interaction. Many ASA assay methods have been developed, each with advantages and disadvantages. Efforts for the treatment of ASA-mediated infertility have been attempted. However, current therapy for ASA-associated infertility is almost empiric and largely unproven.

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.

Antiphospholipid inner ear syndrome

OBJECTIVE

This study was initiated to clarify the possible association between antiphospholipid antibodies, mediators of microthrombus formation, and sensorineural hearing loss (SNHL) of unknown origin in a large cohort of patients.

STUDY DESIGN

Prospective study.

METHODS

The study cohort consists of 168 adult patients (>/=18 yr) referred to the University of Pennsylvania's Division of Neurotology and Balance Center for diagnosis and treatment of progressive hearing loss with or without vertigo. A comprehensive screening panel of blood tests for autoimmune and infectious diseases was applied to all patients, including testing for anticardiolipin antibodies, anti-B2 glycoprotein, and lupus anticoagulant.

RESULTS

Forty-two patients (25%) had at least one elevated antiphospholipid antibody marker. Twenty patients had two or more positive test results. Of the 42 patients, 64% (n = 27) met the diagnostic criteria for Meniere disease, and the remainder were diagnosed with idiopathic SNHL. Within this group of patients, 24 patients (57%) had unilateral hearing loss, and 18 (44%) had bilateral hearing loss.

CONCLUSIONS

These data support the hypothesis that antiphospholipid antibodies are involved in the pathogenesis of some forms of inner ear dysfunction, presumably by causing microthrombus formation in the labyrinthine vasculature. Basic science studies are required to better understand the mechanisms by which antiphospholipid antibodies mediate inner ear dysfunction. Clinical studies to evaluate the efficacy of anticoagulation in this group of patients are also required.

Antiphospholipid syndrome: association between laboratory tests and clinical practice

Antiphospholipid antibodies are a wide and heterogeneous group of immunoglobulins, whose presence inpatients with arterial and venous thrombosis, and obstetrical complications defines the antiphospholipid syndrome. We systematically reviewed published articles on this syndrome to investigate the association between thrombosis and the most common antiphospholipid antibodies. Lupus anticoagulants were a clear risk factor for thrombosis, irrespective of the site and type of thrombosis, the presence of systemic lupus erythematosus, and the methods used to detect them. Anticardiolipin and anti 2-glycoprotein I antibodies were possible risk factors of thrombosis, at least in some selected situations. Conversely, the measurement of antiprothrombin antibodies was not helpful to define the patient's risk of thrombosis. These results are mainly due to the still far from optimal standardization of the methods to detect the various antiphospholipid antibodies.

Antiphospholipid antibodies in implantation failures

PROBLEM

The amino phospholipids (PL), phosphatidylserine (PS) and phosphatidylethanolamine (PE) are distributed asymmetrically in the plasma membranes of eucaryotic cells. This arrangement involves active transport of PS and PE from the outer to inner membrane leaflet by an aminophospholipid translocase (flipase). Cell activation, injury and programmed cell death (apoptosis) cause collapse of the PS/PE asymmetry by activation of another enzyme system, scramblase. Unlike other cells, the developing trophoblast exteriorizes PS during its differentiation.

METHODS OF STUDY

An analysis of published and unpublished data.

RESULTS

The trophoblast is targeted by antiphospholipid antibodies (aPL), especially to PS (aPS). Cardiolipin is not present in the trophoblast plasma membrane, nonetheless, anticardiolipin (aCL) has been implicated in trophoblast pathology. The aPS and aCL are often crossreactive. Both animal and in vitro experimental models have shown monoclonal and polyclonal aPS and aCL to specifically destroy trophoblast, inhibit syncytium formation, halt human chorionic gonadatropin (hCG) production, and limit trophoblast invasion. Antibodies to PE (aPE) have not been well characterized, however, recent reports from several independent laboratories document that aPE are associated significantly with very early (embryonic) recurrent pregnancy loss (RPL). Umeda and coworkers have shown that during cytokinesis (late telophase) of Chinese hamster ovary (CHO) cells, formation of PE rafts in cleavage furrows is required for completion of cell division and formation of daughter cells. This raises the question whether aPE might interfere with implantation and cell division during embryogenesis.

CONCLUSIONS

A role for aPL in implantation failure and occult pregnancy loss constitutes the basis of this overview.

Clinical significance of beta 2-glycoprotein I-dependent anticardiolipin antibodies in the reproductive autoimmune failure syndrome: correlation with conventional antiphospholipid antibody detection systems

OBJECTIVE

Our purpose was to determine whether beta 2-glycoprotein I-dependent anticardiolipin antibodies may represent a superior marker of reproductive risk than do conventional antiphospholipid antibodies.

STUDY DESIGN

The incidence of beta 2-glycoprotein I-dependent and beta 2-glycoprotein I-independent anticardiolipin antibodies and of six conventional antiphospholipid antibodies was statistically compared between study groups with and without autoantibody-associated features of reproductive failure. Sera from 356 women were randomly selected from the frozen sera bank at the Center for Human Reproduction, Chicago. They included sera from 259 patients with autoantibody-associated features of reproductive failure such as unexplained infertility, endometriosis, and repeated pregnancy loss and 97 infertile controls. Autoantibody levels by a modified enzyme-linked immunosorbent assay for beta 2-glycoprotein I-dependent and beta 2-glycoprotein I-independent anticardiolipin antibodies and a standard enzyme-linked immunosorbent assay for anticardiolipin antibody and five other antiphospholipid antibodies were then compared.

RESULTS

Patients demonstrated a significantly higher incidence of beta 2-glycoprotein I-dependent anticardiolipin antibodies (5.4%) than did controls (0%) in a modified enzyme-linked immunosorbent assay (p = 0.01). No such difference was, however, noted for beta 2-glycoprotein I-independent anticardiolipin antibodies or any one of six antiphospholipid antibodies. Two or more among six antiphospholipid antibodies, especially if involving anticardiolipin antibodies, antiphosphatidylserine and antiphosphatidylinositol, as assayed by standard enzyme-linked immunosorbent assay, were significantly more often (p = 0.02) positive in the patients (5.0%) than in the controls (0%). Moreover, positivity in two of those three antiphospholipid antibodies correlated in 59% of cases to positivity in the beta 2-glycoprotein I-dependent anticardiolipin antibody.

CONCLUSIONS

As a single test beta 2-glycoprotein I-dependent anticardiolipin antibody appears to be superior to cofactor-independent anticardiolipin antibody or any other single conventional antiphospholipid antibody for the detection of autoantibody-associated conditions of reproductive failure. A broadly based panel of conventional antiphospholipid antibodies, especially if inclusive of anticardiolipid antibody, antiphosphatidylserine, and antiphosphatidylinositol, may, however, achieve similar results.

Autoantibody profiles and immunoglobulin levels as predictors of in vitro fertilization success

OBJECTIVE

Our aim was to determine the predictive value of autoantibody and immunoglobulin determinations as indicators of the success of in vitro fertilization.

STUDY DESIGN

This was a blinded study in which laboratory evaluations were performed on coded samples obtained from another institution. Codes were broken and data were analyzed after results of all laboratory tests had been reported out. One hundred five infertility patients who had undergone in vitro fertilization were randomly chosen. Among those, 46 were considered low responders (six or fewer oocytes were retrieved) and 59 as high responders (13 to 30 oocytes were retrieved). Total immunoglobulin G, M, and A levels and 15 autoantibody levels (6 antiphospholipids, 5 antihistones, and 4 antipolynucleotides) were determined separately for immunoglobulin G, immunoglobulin M, and immunoglobulin A isotypes.

RESULTS

High and low responders demonstrated an unusual incidence of autoantibody (25% and 30%, respectively) and immunoglobulin (46% and 48%, respectively) abnormalities. They did not differ from each other, however, in either immunoglobulin or autoantibody parameters. Autoantibody and immunoglobulin abnormalities alone or in combination did not predict pregnancy success (24% vs 16%), incidence of chemical pregnancies (15% vs 24%), or clinical pregnancy loss (9% vs 11%) when such women were compared with those without either abnormality. However, the occurrence of hypergammaglobulinemias, in contrast to hypogammaglobulinemias, was associated with a significant decrease in the clinical pregnancy rate (6% vs 24%, p = 0.05).

CONCLUSIONS

Neither autoantibody abnormalities nor total immunoglobulin abnormalities allow differentiation between high and low responders in in vitro fertilization cycles. The presence of autoantibody and total immunoglobulin abnormalities also does not predict low clinical pregnancy rates. Within a group of women with immunoglobulin abnormalities, those with hypergammaglobulinemias appear, however, at significant risk for low pregnancy rates with in vitro fertilization. This observation suggests that high total immunoglobulin levels may serve as a marker for an as yet to be determined immunologic factor that adversely affects the chance of conception. The evaluation of total immunoglobulin levels may be indicated as part of a routine infertility workup.

Antiphospholipid antibodies in pregnancy: prevalence and clinical associations

OBJECTIVE

To determine prevalence, clinical association and predictive power of antiphospholipid antibodies in pregnancy.

DESIGN

To test for the presence of anticardiolipin antibodies and lupus anticoagulant in order to confirm prevalence data which imply that each antibody has the same clinical significance. A detailed obstetric history and the outcome measures were obtained from each patient in the study.

SETTING

National Women's Hospital, Auckland, New Zealand.

SUBJECTS

Nine hundred and thirty-three consecutively booked pregnant women.

MAIN OUTCOME MEASURES

Prevalence of auto-antibodies; perinatal morbidity and mortality; incidence of pre-eclampsia, growth retardation and fetal distress.

RESULTS

Nine women (1.0%) had anticardiolipin antibodies, 11 (1.2%) had lupus anticoagulant and two had both antibodies. The fetal mortality rate for women with antibodies was 167/1000. Pre-eclampsia occurred significantly more often in women with auto-antibodies.

CONCLUSION

The presence of antiphospholipid antibodies is frequently associated with adverse pregnancy outcome (9/18 pregnancies). High titre anticardiolipin antibodies carry a poor prognosis.

Lack of expression of HLA antigens on immature germ cells from ejaculates with antisperm antibodies

PROBLEM

The lack of expression of HLA antigen on immature germ cells from ejaculates with antisperm antibodies has been reported.

METHOD

The expression of human leukocyte antigens on immature germ cells from ejaculates with antisperm antibodies (ASA) was investigated by indirect immunofluorescence using a panel of monoclonal antibodies (MAb) and automated flow cytometry. Patients were divided into two groups: fertile (prevasectomic; N = 10), and ejaculates with ASA (10 samples with IgG and IgA ASA, and five semen samples with only IgG ASA). ASA were detected on sperm using the direct immunobead test. After centrifuging semen samples on a Ficoll-Hypaque gradient, round cells obtained at the gradient interface were gated by a flow cytometer. The "immature germ cell window" was defined in terms of cellular volume and granularity.

RESULTS

The percentage of gated round cells from semen samples that reacted with anti-CD45 was always less than 5%, and with anti-CD44 less than 3%. This lack of reactivity of gated round cells with MAb specific for leukocytes and epithelial cells suggests that they were immature germ cells. Immature germ cells were unreactive with W6/32 and anti-beta-2-microglobulin MAb, which suggests that these cells do not express HLA class I molecules. Similarly, no reactivity of the immature germ cells with the MAb that recognize HLA class II molecules was found. No significant differences were observed in the expression of HLA molecules on immature germ cells between the different semen samples studied: fertile, and ejaculates with ASA.

CONCLUSION

The presence of ASA in ejaculate is not associated with abnormal HLA antigen expression on immature germ cells.

Influence of immunotherapy on antisperm antibody titer in unexplained recurrent aborters

PROBLEM

The mechanism of the beneficial effect of immunotherapy for human reproductive wastage remains to be elucidated. Because some women with unexplained recurrent spontaneous abortion are immunized with their partner's lymphocytes, it is important to determine whether such immunization results in elevation or enhancement of immunity to spermatozoa, because antigenic cross-reactivity between lymphocytes and spermatozoa has been reported.

METHOD

The present study was initiated to evaluate the changes in antisperm antibody titer and lymphocyte subsets after immunotherapy as compared to before immunotherapy. Antisperm antibody detection was performed by SpermCheck Assay, which is based on a modification of the immunobead test. Maternal lymphocyte subsets were analyzed in two-color flow-cytometric experiments.

RESULTS

The percentage of antibody-positive sperm decreased significantly (P = 0.0008) after immunotherapy. The percentage of B(CD19+) cells (P = 0.0003), cytotoxic T(CD8+ and CD11b-) cells (P = 0.02) and the Th/Ts ratio (P = 0.005) decreased significantly, while suppressor T(CD8+ and CD11b+) cells increased significantly (P = 0.0002) after the immunotherapy. This suggests that cell-mediated immunosuppression was induced by immunotherapy.

CONCLUSION

The data of the present study suggest that antisperm antibodies have potential for use as a marker for a deficiency in maternal genital tract immunosuppressor mechanisms and that immunotherapy could be an effective treatment for women with antisperm antibodies who have unexplained recurrent abortions.

What do we really know about autoantibody abnormalities and reproductive failure: a critical review

CONDENSATION

The diagnosis and treatment of autoantibody-associated forms of reproductive failure is critically reviewed.

OBJECTIVE

To critically evaluate the published literature in reference to autoantibody-associated forms of reproductive failure.

LOCATION

Medical School-affiliated private Infertility Center.

MATERIALS

A review of over 200 published papers reflecting on the topic.

RESULTS

Autoantibody associated reproductive failure, characterized by a decrease in fecundity and an increase in the risk of pregnancy loss, appears established. Autoantibody abnormalities, as routinely detected by standard laboratory assays, are, however, neither immunologically nor biologically specific since cross reactivities between autoantibodies are frequent and a specific autoantibody may cause a biological effect in one but not in another affected individual.

CONCLUSIONS

The evaluation of autoantibody abnormalities in all cases of suspected autoimmune-associated reproductive failure is valuable and will improve clinical care of affected patients. Clinicians need, however, to recognize the limitations of autoantibody testing and have to adjust their clinical management to the degree and quality of autoantibody evaluation available to them in their community.

Autoantibodies in normal and abnormal pregnancy

Abnormal autoimmune function has been associated with reproductive failure for decades. In fact, all medical conditions historically associated with pregnancy loss (and on occasion infertility) are now recognized to have an autoimmune etiology. It is therefore quite surprising that only less than a decade ago a correlation between the presence of abnormal autoantibodies and pregnancy loss was reported for the first time. Since reproductive failure, similar to other abnormal autoimmune states, is not a monoclonal event, we have established that affected patients demonstrate polyclonal autoantibody abnormalities including a variety of nonorganospecific as well as organspecific autoantibody groupings. For example, patients with repeated pregnancy loss will exhibit abnormal levels of anti-phospholipid antibodies (PA). In normal pregnancy natural autoantibodies do not follow the standard immunoglobulin (Ig) pattern, characterized by a decrease in levels despite a probably mild increase in production, which is excessively compensated by the vasodilatation of pregnancy. PA, especially, demonstrate a mild increase during pregnancy, though levels only in the peripartal period may reach abnormally high titers (in comparison to nonpregnant controls). This dichotomy between total Ig and natural autoantibodies is interesting since it suggests that autoantibodies may be under distinct control. In fact, we have suggested that this observed elevation of autoantibodies may be the result of an antigenic stimulus by self-like antigen, represented by the maternal growth of the parasitic fetus. In abnormal pregnancies, especially those associated with maternal hypertension and fetal growth retardation (IUGR), autoantibody levels do reach highly abnormal levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Presence of autoantibodies in women with unexplained infertility

Serum samples from 41 patients suffering from unexplained infertility and 351 normal pregnant women were assayed for a range of autoantibodies by means of immunofluorescence, counterimmunoelectrophoresis, double immunodiffusion, Western blots, and enzyme-linked immunosorbent assays. The prevalence of autoantibodies to smooth muscle, phospholipid, and nuclear antigens, the latter when detected by immunofluorescence, was elevated in women with infertility compared with normal pregnant women (p less than 0.001, less than 0.001, and less than 0.05, respectively). Antiviral antibodies were not detected. The reason for the high level of autoreactivity in infertile women is unclear, but smooth muscle and antiphospholipid antibodies may actively interfere with the reproductive process.

The reproductive autoimmune failure syndrome

The association between reproductive failure and abnormal autoimmune function has been recognized for decades in association with such established autoimmune diseases as systemic lupus erythematosus. Recent investigations have expanded this association to women who demonstrate similar humoral abnormalities as patients with defined autoimmune diseases but do not express any of the clinical symptoms required for the diagnosis of an autoimmune disease. The observation that abnormal autoimmune function in clinically asymptomatic patients can lead to reproductive failure has led us to define the reproductive autoimmune failure syndrome as a diagnostic entity. The present article summarizes evidence suggesting that the occurrence of reproductive autoimmune failure syndrome may be teleologically related to the woman's need for increased self-tolerance in face of antigenic exposure to the maternal haplotype of the fetus during normal pregnancy. This need for increased self-tolerance is documented by higher normal autoantibody levels in women than in men and may also be responsible for the highly increased incidence of autoimmune diseases in women in comparison with men. Under this concept, abnormal autoimmune function may lead to reproductive failure at different stages of the reproductive process, depending on the quality and possibly quantity of the abnormal autoimmune response.