Endometrial antibodies in serum and peritoneal fluid of infertile patients with and without endometriosis

Tertiary lymphoid structures in endometriosis

OBJECTIVE

To determine whether tertiary lymphoid structures (TLSs), which reflect organized immune cell aggregates present in non-lymphoid tissues, are consistent features of endometriosis lesions.

DESIGN

Detailed histopathological analysis of endometrial and lesion tissue from patients with endometriosis and controls was performed. Multiplex immunofluorescence on select samples was then conducted to identify canonical cell populations present within TLSs: CD3+ and CD8+ T-cells, CD79a+ B-cells, CD208+ dendritic cells, CD21+ follicular dendritic cells, and PNAd+ high endothelial venules.

PATIENT(S)

Patients with histologically confirmed endometriosis (N = 113; 44.3 ± 6.0) and control individuals (N = 110; 44.6 ± 7.1).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURE(S)

Detection of TLSs as characterized by the presence of all canonical cell types that constitute TLS and structure morphology.

RESULT(S)

Of the selected samples (N = 18; 6 ectopic/eutopic/control), mature TLSs were identified in 3 ectopic tissue samples present on the ovary and fallopian tube, with immature TLSs (lacking follicular dendritic cell networks and high endothelial venules) present throughout eutopic and control endometrial samples.

CONCLUSION

These findings demonstrate the presence of TLSs across various endometriosis phenotypes, prompting further research into their significance within disease pathophysiology and the prognostic implications for patients.

The effects of Rituximab on experimental endometriosis model in rats

AIM

Endometriosis is a common, chronic benign gynecologic disease and distresses women in their reproductive age. Yet the pathogenesis of endometriosis is not clear, multifactorial mechanisms have been characterized for the initiation, progression, and regression of this disease. It has been suggested that immune cells in the lymphoid lineage play essential roles in accepting or rejecting the survival, implantation, and proliferation of endometrial and endometriotic cells and, dysfunction of B-lymphocytes (B-cells) are one of the major causes for the progression of endometriosis. In this study, we aimed to evaluate the potential therapeutic efficacy of Rituximab, an inhibitor for B-cells, for endometriosis in an experimental animal model.

METHODS

Experimental endometriosis animal model has been utilized using mature female rats. Rats underwent surgery to initiate endometriosis on the abdominal wall. After confirming for endometriosis, rats were treated with either Rituximab or saline solution. After 14 days of treatment, implants were dissected, and evaluated for volumes and histological features. Anti-CD-20 antibody was used for immunohistochemistry scoring purposes.

RESULTS

There is significant decrease in the volume of endometriotic implants after treatment with Rituximab (188.81 ± 149.42 vs 20.37 ± 13.08, p = 0.001). There are also significant differences for the B-cell count and fibrosis score between the control and treatment groups (3.08 ± 2.6 vs 1.56 ± 1.42., p = 0.043).

CONCLUSION

In an experimental rat endometriosis model, we assessed Rituximab, an antibody for B-lymphocyte, as a candidate medical treatment for endometriosis. Additional studies are required to further evaluate the effects of Rituximab on the prevention of endometriosis.

Sex hormones, body mass index, and related comorbidities associated with developing Sjögren's disease: a nested case-control study

OBJECTIVE

Sjögren's disease (SjD), a highly female predominant systemic autoimmune disease, peaks in perimenopause. Prior studies lack details on timing or type of sex hormone exposure. We examined SjD risk using endogenous and exogenous hormone exposure and related comorbidities.

METHODS

We performed a retrospective case-control study of adult women, nested within a population cohort. Cases had SjD diagnosed by a rheumatology provider or two SjD diagnoses from a non-rheumatology provider with a positive anti-SSA antibody or salivary gland biopsy. Cases were age-matched to three SjD-free controls. We calculated modified composite estrogen scores (mCES) and collected demographics, comorbidities, and endogenous and exogenous hormone exposures. Risk ratios were adjusted for demographics.

RESULTS

Of 546 SjD cases and 1637 age-matched controls, mCES was not significantly associated with SjD in adjusted models. The top individual hormone exposures associated with SjD included estrogen replacement therapy (ERT; RR 1.78 [95% CI 1.47-2.14]), polycystic ovarian syndrome (1.65 [1.28-2.12]), and hysterectomy without bilateral oophorectomy (1.51 [1.13-2.03]). We identified comorbidities preceding SjD including fibromyalgia, pulmonary disease, diabetes, lymphoma, osteoporosis, peripheral vascular disease, and renal disease. Taking comorbidities into account, we developed a predictive model for SjD that included fibromyalgia (2.50 [1.93-3.25]), osteoporosis (1.84 [1.27-2.66]), hormone replacement therapy (HRT) (1.61 [1.22-2.12]), diabetes (0.27 [0.13-0.50]), and body mass index (BMI) (0.97 [0.95-0.99]).

CONCLUSIONS

We report a novel algorithm to improve identifying patients at risk for SjD and describe sex hormone association with SjD. Finally, we report new comorbidities associated with SjD decrease, BMI and diabetes, and increase, lymphoma and osteoporosis.. Key Points •Given female predominance and typical perimenopausal onset, sex hormones should be considered when studying comorbidities in Sjögren's disease. •The top exposures associated with developing Sjögren's disease included fibromyalgia, osteoporosis, and use of hormone replacement therapy. Possible protective factors included prior diabetes and higher body mass index. •We used our newly identified exposures to generate a predictive algorithm, which has potential to improve diagnosis and pathogenic insights into Sjögren's disease.

Supplementation with vitamin D or ω-3 fatty acids in adolescent girls and young women with endometriosis (SAGE): a double-blind, randomized, placebo-controlled trial

BACKGROUND

Adolescents with endometriosis are a particularly underserved population who struggle with chronic pain. Despite widespread use, there are no published trials examining the individual effects of vitamin D and omega-3 (n-3) fatty acid supplementation on endometriosis-associated pain in adolescents.

OBJECTIVES

We aimed to determine whether supplementation with vitamin D or ω-3 fatty acids remediates pain, changes frequency of pain medication usage, or affects quality of life in young women with endometriosis.

METHODS

Women (aged 12-25 y) with surgically confirmed endometriosis and pelvic pain enrolled in a double-blind, randomized, placebo-controlled trial. The primary outcome was pain measured by the visual analog scale (VAS). Secondary outcomes were quality of life, pain catastrophizing, and pain medication usage. Participants were randomly assigned to receive 2000 IU vitamin D3, 1000 mg fish oil, or placebo daily for 6 mo.

RESULTS

A total of 147 women were screened and 69 were randomly assigned as follows: 27 to vitamin D3; 20 to fish oil; and 22 to placebo. Participants in the vitamin D arm experienced significant improvement in VAS pain [mean (95% CI) worst pain in the past month, from baseline to 6 mo: 7.0 (6.2, 7.8) to 5.5 (4.2, 6.8), P = 0.02]; however, an improvement of nearly identical magnitude was observed in the placebo arm [6.0 (5.1, 6.9) to 4.4 (3.0, 5.8), P = 0.07]. A more modest improvement was observed in the fish oil arm [5.9 (4.8, 7.0) to 5.2 (3.7, 6.8), P = 0.39]. Neither of the intervention arms were statistically different from placebo.

CONCLUSIONS

In young women with endometriosis, supplementation with vitamin D led to significant changes in pelvic pain; however, these were similar in magnitude to placebo. Supplementation with fish oil resulted in about half of the VAS pain reduction of the other 2 arms. Studies are needed to better define the physiology underlying the observed reduction in pain score in the placebo arm that persisted across 6 mo.This trial was registered at clinicaltrials.gov as NCT02387931.

The link between immunity, autoimmunity and endometriosis: a literature update

Endometriosis (EMS), an estrogen-dependent inflammatory disorder affects approximately 5-10% of the general female population of reproductive age and 20-90% of women with pelvic pain and infertility. Many immunological factors are known to contribute significantly to the pathogenesis and pathophysiology of EMS, and both chronic local inflammation and autoantibodies in EMS shares many similarities with autoimmune diseases (AD). However, the autoimmune etiology in EMS remains controversial, and its evidence on autoimmune basis may be limited. Here we aim to review the current understanding between autoimmunity and EMS to provide important knowledge to develop future potential immunomodulatory therapy for the treatment of EMS.

Blood biomarkers for the non-invasive diagnosis of endometriosis

BACKGROUND

About 10% of reproductive-aged women suffer from endometriosis, a costly chronic disease causing pelvic pain and subfertility. Laparoscopy is the gold standard diagnostic test for endometriosis, but is expensive and carries surgical risks. Currently, there are no non-invasive or minimally invasive tests available in clinical practice to accurately diagnose endometriosis. Although other reviews have assessed the ability of blood tests to diagnose endometriosis, this is the first review to use Cochrane methods, providing an update on the rapidly expanding literature in this field.

OBJECTIVES

To evaluate blood biomarkers as replacement tests for diagnostic surgery and as triage tests to inform decisions on surgery for endometriosis. Specific objectives include:1. To provide summary estimates of the diagnostic accuracy of blood biomarkers for the diagnosis of peritoneal, ovarian and deep infiltrating pelvic endometriosis, compared to surgical diagnosis as a reference standard.2. To assess the diagnostic utility of biomarkers that could differentiate ovarian endometrioma from other ovarian masses.

SEARCH METHODS

We did not restrict the searches to particular study designs, language or publication dates. We searched CENTRAL to July 2015, MEDLINE and EMBASE to May 2015, as well as these databases to 20 April 2015: CINAHL, PsycINFO, Web of Science, LILACS, OAIster, TRIP, ClinicalTrials.gov, DARE and PubMed.

SELECTION CRITERIA

We considered published, peer-reviewed, randomised controlled or cross-sectional studies of any size, including prospectively collected samples from any population of reproductive-aged women suspected of having one or more of the following target conditions: ovarian, peritoneal or deep infiltrating endometriosis (DIE). We included studies comparing the diagnostic test accuracy of one or more blood biomarkers with the findings of surgical visualisation of endometriotic lesions.

DATA COLLECTION AND ANALYSIS

Two authors independently collected and performed a quality assessment of data from each study. For each diagnostic test, we classified the data as positive or negative for the surgical detection of endometriosis, and we calculated sensitivity and specificity estimates. We used the bivariate model to obtain pooled estimates of sensitivity and specificity whenever sufficient datasets were available. The predetermined criteria for a clinically useful blood test to replace diagnostic surgery were a sensitivity of 0.94 and a specificity of 0.79 to detect endometriosis. We set the criteria for triage tests at a sensitivity of ≥ 0.95 and a specificity of ≥ 0.50, which 'rules out' the diagnosis with high accuracy if there is a negative test result (SnOUT test), or a sensitivity of ≥ 0.50 and a specificity of ≥ 0.95, which 'rules in' the diagnosis with high accuracy if there is a positive result (SpIN test).

MAIN RESULTS

We included 141 studies that involved 15,141 participants and evaluated 122 blood biomarkers. All the studies were of poor methodological quality. Studies evaluated the blood biomarkers either in a specific phase of the menstrual cycle or irrespective of the cycle phase, and they tested for them in serum, plasma or whole blood. Included women were a selected population with a high frequency of endometriosis (10% to 85%), in which surgery was indicated for endometriosis, infertility work-up or ovarian mass. Seventy studies evaluated the diagnostic performance of 47 blood biomarkers for endometriosis (44 single-marker tests and 30 combined tests of two to six blood biomarkers). These were angiogenesis/growth factors, apoptosis markers, cell adhesion molecules, high-throughput markers, hormonal markers, immune system/inflammatory markers, oxidative stress markers, microRNAs, tumour markers and other proteins. Most of these biomarkers were assessed in small individual studies, often using different cut-off thresholds, and we could only perform meta-analyses on the data sets for anti-endometrial antibodies, interleukin-6 (IL-6), cancer antigen-19.9 (CA-19.9) and CA-125. Diagnostic estimates varied significantly between studies for each of these biomarkers, and CA-125 was the only marker with sufficient data to reliably assess sources of heterogeneity.The mean sensitivities and specificities of anti-endometrial antibodies (4 studies, 759 women) were 0.81 (95% confidence interval (CI) 0.76 to 0.87) and 0.75 (95% CI 0.46 to 1.00). For IL-6, with a cut-off value of > 1.90 to 2.00 pg/ml (3 studies, 309 women), sensitivity was 0.63 (95% CI 0.52 to 0.75) and specificity was 0.69 (95% CI 0.57 to 0.82). For CA-19.9, with a cut-off value of > 37.0 IU/ml (3 studies, 330 women), sensitivity was 0.36 (95% CI 0.26 to 0.45) and specificity was 0.87 (95% CI 0.75 to 0.99).Studies assessed CA-125 at different thresholds, demonstrating the following mean sensitivities and specificities: for cut-off > 10.0 to 14.7 U/ml: 0.70 (95% CI 0.63 to 0.77) and 0.64 (95% CI 0.47 to 0.82); for cut-off > 16.0 to 17.6 U/ml: 0.56 (95% CI 0.24, 0.88) and 0.91 (95% CI 0.75, 1.00); for cut-off > 20.0 U/ml: 0.67 (95% CI 0.50 to 0.85) and 0.69 (95% CI 0.58 to 0.80); for cut-off > 25.0 to 26.0 U/ml: 0.73 (95% CI 0.67 to 0.79) and 0.70 (95% CI 0.63 to 0.77); for cut-off > 30.0 to 33.0 U/ml: 0.62 (95% CI 0.45 to 0.79) and 0.76 (95% CI 0.53 to 1.00); and for cut-off > 35.0 to 36.0 U/ml: 0.40 (95% CI 0.32 to 0.49) and 0.91 (95% CI 0.88 to 0.94).We could not statistically evaluate other biomarkers meaningfully, including biomarkers that were assessed for their ability to differentiate endometrioma from other benign ovarian cysts.Eighty-two studies evaluated 97 biomarkers that did not differentiate women with endometriosis from disease-free controls. Of these, 22 biomarkers demonstrated conflicting results, with some studies showing differential expression and others no evidence of a difference between the endometriosis and control groups.

AUTHORS' CONCLUSIONS

Of the biomarkers that were subjected to meta-analysis, none consistently met the criteria for a replacement or triage diagnostic test. A subset of blood biomarkers could prove useful either for detecting pelvic endometriosis or for differentiating ovarian endometrioma from other benign ovarian masses, but there was insufficient evidence to draw meaningful conclusions. Overall, none of the biomarkers displayed enough accuracy to be used clinically outside a research setting. We also identified blood biomarkers that demonstrated no diagnostic value in endometriosis and recommend focusing research resources on evaluating other more clinically useful biomarkers.

Effect of Endometriosis on IVF Outcomes in Cases of Single Embryo Transfer for first IVF Attempt in Patients under 35

Background

Implantation disorders are regarded differently in different groups undergoing in vitro fertilization (IVF) because of heterogeneous patient populations. To avoid this problem, this study was based solely on the first attempts of a single embryo transfer in patients under the age of 35.

Methods

This was a retrospective comparative study with 2 groups of patients: a group with endometriosis (n = 288) and a group without endometriosis (n = 1,368), registered from January 2010 to December 2013 in the IVF center of the University Hospital of Clermont-Ferrand. This study compared the 2 groups and subgroups according to ovarian response and embryo quality, and analyzed oocyte number, embryo number, transfer rate, implantation rate and delivery rate per ovum pick-up and per transfer.

Results

In the cases of endometriosis, the number of collected oocytes (8.37 ± 7.01 vs. 10.13 ± 6.53 p<0.001), the transfer rate (81.4% vs. 86.1%, p = 0. 045) and the rate of cycles with a frozen embryo (48.9% vs. 57.3%, p<0.01) were lower. The probability of a satisfactory response to stimulation (70.7% vs. 81.0%, p<0.001) and of a good quality embryo cohort (45% vs. 52%, p = 0.003) was lower. However, the implantation and delivery rates per transfer were not distorted in the cases of endometriosis, either in the total group or in any subgroup. The cumulative live birth rate per attempt was similar (29.2% vs. 29.5%).

Conclusions

Endometriosis has no impact on the embryo transfer in IVF, particularly when the embryo quality is satisfactory.

Investigation of serum proteome alterations in human endometriosis

Endometriosis is a common benign gynecological disease, characterized by proliferation of functional endometrial glands and stroma outside the uterine cavity. The present study involves investigation of alterations in the serum proteome of endometriosis patients compared to healthy controls using 2DE and 2D-DIGE combined with MALDI TOF/TOF-MS. Comparison of serum proteome of endometriosis patients and healthy subjects revealed 25 significant differentially expressed proteins. Gene ontology and network analysis, performed using PANTHER, DAVID, WebGestalt and STRING, revealed that the differentially expressed proteins are majorly involved in response to stimulus, immune system, metabolic, localization and cellular processes. For serum diagnostic marker identification, several robust statistical screening procedures were applied to identify the set of the most significant proteins responsible for successful diagnosis of different endometriosis stages. Partial least squares (PLS) based marker selection tool and orthogonal partial least squares-discriminant analysis (OPLS-DA) were used to identify the most significant proteins for disease prediction. Western blotting validation in a separate cohort of patients revealed that haptoglobin (HP), Ig kappa chain C region (IGKC), alpha-1B-glycoprotein (A1BG) can be considered effective serum protein markers for the diagnosis of Stage II, III and IV endometriosis. For diagnosis of Stage I, only IGKC and HP seemed promising.

BIOLOGICAL SIGNIFICANCE

Globally, about 12 in 100 women of reproductive age are diagnosed with endometriosis. The pathogenesis of the disease still remains unclear, leading to non-specific therapeutic approaches for disease management. Moreover, there is a delay of 8-12years in correct diagnosis after the initial onset of symptoms leading to a considerable impact on the woman's lifestyle. Also, the gold standard for diagnosis of endometriosis, laparoscopy, is an invasive procedure. The value of a noninvasive or semi-invasive diagnostic test for endometriosis with easily accessible fluids such as plasma, serum, urine, and saliva is, therefore, rightfully recognized. The present study is expected to considerably improve the understanding of the disease pathogenesis along with improved diagnostics and therapeutic approaches leading to better management of the disease.

The peritoneum--an important factor for pathogenesis and pain generation in endometriosis

Endometriosis (EM) is an oestrogen-dependent disease affecting 10-15 % of women during reproductive age. It is characterised by the presence of endometrial glands, stromal- and smooth muscle-like cells outside of the uterine cavity. Fifty to sixty per cent of women and teenage girls with pelvic pain suffer from EM. EM causes disability and compromises the quality of life in women and young girls significantly. Pain generation in EM is an intricate interplay of several factors such as the endometriotic lesions themselves and the pain-mediating substances, nerve fibres and cytokine-releasing immune cells such as macrophages. These interactions seem to induce a neurogenic inflammatory process. Recently published data demonstrated an increased peptidergic and decreased noradrenergic nerve fibre density in peritoneal lesions. These data could be substantiated by in vitro analyses demonstrating that the peritoneal fluids of patients suffering from EM induced an enhanced sprouting of sensory neurites from chicken dorsal root ganglia and decreased neurite outgrowth from sympathetic ganglia. These findings might be directly involved in the perpetuation of inflammation and pain. Furthermore, the evidence of EM-associated smooth muscle-like cells seems another important factor in pain generation. The peritoneal endometriotic lesion leads to reactions in the surrounding tissue and, therefore, is larger than generally believed. The identification of EM-associated nerve fibres and smooth muscle-like cells fuel discussions on the mechanisms of pain generation in EM, and may present new targets for innovative treatments.

Endometriosis-associated infertility: double intrauterine insemination improves fecundity in patients positive for antiendometrial antibodies

PROBLEM

Prospective registry study evaluating effects of endometriosis (E) and serum antiendometrial antibodies (AEA) on fecundity in intrauterine insemination (IUI) cycles.

METHOD OF STUDY

AEA assays on 572 consecutive women receiving 969 single and 274 double IUI cycles. Logistic regression was utilized.

RESULTS

Fecundity was 11.5% (143/1243 cycles). Double IUI improved fecundity with significance achieved in certain study groups. Compared to the AEA- subgroup, all study groups except for the E+ AEA- group had significantly lower fecundity. Two study groups receiving double IUI had significantly increased fecundity, E- AEA+ (OR: 5.1, CI: 1.1-22.7, P=0.032) and E+ AEA+ (OR: 4.1, CI: 1.2-14.0, P=0.025) and significant predictors of pregnancy (E- AEA+, OR: 7.8, CI: 1.7-36.2, P=0.009 and E+ AEA+, OR: 4.2, CI: 1.2-15.1, P=0.026).

CONCLUSION

Double IUI improves fecundity in AEA+ patients. E-associated infertility is better diagnosed by the AEA assay than by surgery. Double IUI should be attempted prior to assisted reproductive technologies in AEA+ patients with normal fallopian tubes.

A possible mechanism of autoimmune-mediated infertility in women with endometriosis

PROBLEM

Endometriosis has been proposed to be an autoimmune disease because of the presence of a variety of autoantibodies specific for endometrial or ovarian antigens. The object of the present study is to characterize binding specificity of anti-laminin-111 autoantibodies in infertile patients with endometriosis and to investigate whether these autoantibodies affect the in vitro embryo development.

METHOD OF STUDY

An ELISA analysis using overlapping synthesized peptides that covered the entire G domain of laminin-α1 chain was performed in infertile patients with endometriosis (n = 45). Mouse blastocysts were cultured in media containing the purified IgG from one antibody-positive serum on laminin-111-coated dishes.

RESULTS

Anti-laminin-111 autoantibodies were directed to several particular biologically functional peptide sequences in laminin-α 1 chain G domain. The tested IgG significantly inhibited the extent of in vitro trophoblast outgrowth.

CONCLUSION

Anti-laminin-111 autoantibodies may have major pathogenic roles on early reproductive failure including endometriosis-associated infertility.

Peripheral biomarkers of endometriosis: a systematic review

BACKGROUND

Endometriosis is estimated to affect 1 in 10 women during the reproductive years. There is often delay in making the diagnosis, mainly due to the non-specific nature of the associated symptoms and the need to verify the disease surgically. A biomarker that is simple to measure could help clinicians to diagnose (or at least exclude) endometriosis; it might also allow the effects of treatment to be monitored. If effective, such a marker or panel of markers could prevent unnecessary diagnostic procedures and/or recognize treatment failure at an early stage.

METHODS

We used QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criteria to perform a systematic review of the literature over the last 25 years to assess critically the clinical value of all proposed biomarkers for endometriosis in serum, plasma and urine.

RESULTS

We identified over 100 putative biomarkers in publications that met the selection criteria. We were unable to identify a single biomarker or panel of biomarkers that have unequivocally been shown to be clinically useful.

CONCLUSIONS

Peripheral biomarkers show promise as diagnostic aids, but further research is necessary before they can be recommended in routine clinical care. Panels of markers may allow increased sensitivity and specificity of any diagnostic test.

Differential expression of microRNAs between eutopic and ectopic endometrium in ovarian endometriosis

Endometriosis, defined as the presence of endometrial tissue outside the uterus, is a common gynecological disease with poorly understood pathogenesis. MicroRNAs are members of a class of small noncoding RNA molecules that have a critical role in posttranscriptional regulation of gene expression by repression of target mRNAs translation. We assessed differentially expressed microRNAs in ectopic endometrium compared with eutopic endometrium in 3 patients through microarray analysis. We identified 50 microRNAs differentially expressed and the differential expression of five microRNAs was validated by real-time RT-PCR in other 13 patients. We identified in silico their predicted targets, several of which match the genes that have been identified to be differentially expressed in ectopic versus eutopic endometrium in studies of gene expression. A functional analysis of the predicted targets indicates that several of these are involved in molecular pathways implicated in endometriosis, thus strengthening the hypothesis of the role of microRNAs in this pathology.

Multiple endometrial antigens are targeted in autoimmune endometriosis

Endometriosis is defined as the growth of endometrial glands and stroma in ectopic locations. Its aetiology is multifactorial, but autoimmunity has been shown to play a role in its onset and development. The present study aimed to investigate the presence of both IgG and IgM anti-endometrial antibodies in sera of endometriosis patients in comparison with age-matched controls, and to also investigate the cognate endometrial proteins involved. Sera from these groups were screened by western blot and immunohistochemistry. Thirteen out of the 40 sera tested were positive for IgG isotype, and 10/27 IgG negative patients were positive for IgM isotype. These findings indicate that endometrial antibodies of IgG and IgM classes could be detected in almost 60% of endometriosis patients. Of the various identified endometrial antigens, 30 and 45 kDa antigens were immunodominant in both IgG and IgM positive endometriosis patients. With immunohistochemistry, positive sera showed reactivity in luminal epithelium, glandular epithelium and stroma. These anti-endometrial antibodies might be partially responsible for failure of implantation leading to infertility. Identification of specific targets would be a help in understanding the pathophysiology of endometriosis, and would also help in setting up a non-invasive test for the diagnosis of endometriosis.

Serum antiendometrial antibodies and diagnosis of endometriosis

PROBLEM

The purpose of the present prospective multi-center study is to investigate the relationship between laparoscopic diagnosis of endometriosis and results of a serum antiendometrial antibody (AEA) assay.

METHOD OF STUDY

Indirect immunofluorescence detection of AEA was performed on serum specimens from patients presenting with dysmenorrhea or chronic pelvic pain and infertility (n = 2609) utilizing frozen sections of endometrium acquired on cycle days 18-21 from normally cycling women without endometriosis. Diagnostic laparoscopy was performed within 1 year of AEA assay on 527 tested women.

RESULTS

The relationship between the serum AEA and laparoscopic verification was characterized by a positive predictive value = 88%, negative predictive value = 86%, sensitivity = 87% and specificity = 87%.

CONCLUSION

The AEA assay is a very good screening test for patients suspected of having endometriosis and should be utilized prior to laparoscopy in diagnostic categories of dysmenorrhea or chronic pelvic pain and infertility.

Elevated levels of macrophage migration inhibitory factor in the peripheral blood of women with endometriosis

OBJECTIVE

To evaluate the concentrations of macrophage migration inhibitory factor (MIF) in the peripheral blood of normal women and patients with endometriosis.

DESIGN

Retrospective study using ELISA to measure peripheral blood MIF.

SETTING

Gynecology clinic and human reproduction research laboratory.

PATIENT(S)

Thirty-eight normal women and 55 women with endometriosis.

INTERVENTION(S)

Peripheral blood samples were obtained a few days before laparoscopy.

MAIN OUTCOME MEASURE(S)

The MIF concentrations in blood serum.

RESULT(S)

This current study showed a 364% increase in MIF concentrations in women with endometriosis as compared to normal women. A significant increase was seen in endometriosis stages I-II, but a more marked increase was observed in the more advanced stages of the disease (III-IV). Both fertile and infertile women with endometriosis had higher levels of MIF than normal controls, but the difference was more significant in infertile women with endometriosis. Women with endometriosis with no pelvic pain had higher levels of MIF than normal controls, but a more significant increase in MIF levels was observed in women with endometriosis reporting pelvic pain.

CONCLUSION(S)

This study showed a marked increase in MIF concentrations in the peripheral blood of women with endometriosis and a relationship with disease progress, and suggests that MIF may be involved in endometriosis-related pain and infertility.

Macrophages are activated by 17beta-estradiol: possible permission role in endometriosis

On the basis of the common occurrence of high concentration of estrogen and activated macrophages in patients with endometriosis, we postulate that interaction between 17beta-estradiol and macrophage may be an important affair in endometriosis. So our study was focused on the effect of 17beta-estradiol on macrophage. First morphology of macrophages was examined with environmental scanning electron microscopy. Increased size, extension of more microvilli, expression of retraction fibers and elaboration of membrane ruffles were detected in 17beta-estradiol treated macrophages. Then Nitrate and nitrite level in the supernatant was measured by the method of Griess and iNOS expression was analyzed using immunohistochemical staining. It showed that 17beta-estradiol could induce NO release from peritoneal macrophages and expression of iNOS was increased. Also more TNF-alpha in supernatant that was measured by MTT via L929 cell was produced by macrophages under the inducing of 17beta-estradiol. Furthermore, [Ca2+]i, which was viewed by microscope in a laser scanning confocal unit, elevated 39.8% in peritoneal macrophages after 17beta-estradiol 100 nmol/L treated. The results above demonstrated that peritoneal macrophage had been activated in both morphology and cytokine line when interaction with 17beta-estradiol, which indicated that macrophage activated by 17beta-estradiol might play a permission role in development of endometriosis.

Pathogenesis of endometriosis: natural immunity dysfunction or autoimmune disease?

Endometriosis is a chronic inflammatory disease, characterized by implantation and growth of endometrial tissue outside the uterine cavity. This disabling condition is considered one of the most frequent diseases in gynecology, affecting 15-20% of women in their reproductive life. Pelvic endometriosis, the most common form of the disease, is associated with increased secretion of pro-inflammatory cytokines, neo-angiogenesis, intrinsic anomalies of the refluxed endometrium and impaired function of cell-mediated natural immunity. Recently, endometriosis has also been considered to be an autoimmune disease, owing to the presence of autoantibodies, the association with other autoimmune diseases and recurrent immune-mediated abortion. These findings are in apparent contradiction with the reduced cell-mediated natural immunity observed during the disease. In this review, we focus on the multiple processes underlying the complex pathogenesis of endometriosis, with particular emphasis on the role played by the immune system with the induction of autoimmunity.

Soluble interleukin-1 receptor type II blocks monocyte chemotactic protein-1 secretion by U937 cells in response to peripheral blood serum of women with endometriosis

OBJECTIVE

To assess the ability of peripheral blood serum from women with endometriosis to induce monocyte chemotactic protein-1 (MCP-1) secretion by monocytes and the putative role of the interleukin-1 (IL-1) system in endometriosis-associated monocyte activation.

DESIGN

Cultures of U937 monocytic cells exposed to serum from normal women (control group) or women with endometriosis.

SETTING

Gynecology clinic and human reproduction research laboratory.

PATIENT(S)

Seventy-nine women with endometriosis and 38 control women with no evidence of endometriosis at laparoscopy.

INTERVENTION(S)

Peripheral blood obtained a few days before laparoscopy.

MAIN OUTCOME MEASURE(S)

MCP-1 secretion in the culture medium and serum concentrations of soluble IL-1 receptor type II (sIL-1RII), IL-1beta, and IL-1alpha by ELISA or by enzyme immunometric assay.

RESULT(S)

Serum concentrations of sIL-1RII were significantly lower in women with stage I-II endometriosis than in control women, whereas serum concentrations of IL-1beta and IL-1alpha were comparable between the two groups. The serum of women with endometriosis induced higher secretion of MCP-1 by U937 cells than that of control women, particularly in the initial stages of endometriosis (stages I-II), and recombinant IL-1RII (rIL-1RII) significantly blocked that secretion.

CONCLUSION(S)

These findings point toward a deficiency in the mechanisms involved in the down-regulation of IL-1 actions at the systemic level and reveal sIL-1RII as a key factor involved in that process.

Treating endometriosis as an autoimmune disease

OBJECTIVE

To review the literature on the role of autoimmunity in the etiology of endometriosis, compare the similarities in the pathophysiologies between endometriosis and autoimmune diseases, and discuss the use of immunomodulators currently used to treat autoimmune diseases as potential therapies for endometriosis.

DESIGN

The literature on endometriosis and other autoimmune diseases was reviewed, and summary data are presented.

RESULTS

Endometriosis shares many similarities with autoimmune diseases such as rheumatoid arthritis, Crohn's disease, and psoriasis. These similarities include elevated levels of cytokines, decreased cell apoptosis, and T- and B-cell abnormalities. Because the use of immunomodulators and inflammatory modulators has proven to be an effective means of medical management for these autoimmune diseases, similar therapies may prove useful in treating endometriosis.

CONCLUSION(S)

Although substantial evidence indicates that endometriosis at least shares many similarities with autoimmune diseases, endometriosis is primarily treated by using compounds that induce a hypoestrogenic environment. A review of the literature combined with the shortcomings of current means of medical management for endometriosis support the postulate that treatment of endometriosis with immunomodulators and inflammatory modulators is warranted.

Levels of transferrin and alpha 2-HS glycoprotein in women with and without endometriosis

The study objective was to test the hypothesis that elevated levels of transferrin and alpha 2-HS glycoprotein occur in the peritoneal environment of patients with endometriosis that may lead to the observed autoimmunity to these proteins. We set up a double sandwich enzyme-linked immunosorbent assay (ELISA) for measuring levels of transferrin and alpha 2-HS glycoprotein in the serum and peritoneal fluid samples from women with (n = 24-60) and without endometriosis (n = 35-49). Serum and peritoneal fluid levels of alpha 2-HS glycoprotein and peritoneal fluid levels of transferrin were significantly elevated in patients with endometriosis, in contrast to the controls. Serum levels of transferrin in patients, however, were significantly less in the patients than in controls. We conclude that transferrin and alpha 2-HS glycoprotein are present at high concentrations in the peritoneal fluids of patients with endometriosis. This may play a significant role in the autoimmune pathophysiology of endometriosis.

Effects of antibodies to transferrin and alpha 2-HS glycoprotein on in vitro sperm motion: implications in infertility associated with endometriosis

PROBLEM

Women with endometriosis have antibodies to endometrial transferrin and alpha 2-HS glycoprotein in their serum and peritoneal fluid. The objective of this study was to determine whether antibodies to transferrin and alpha 2-HS glycoprotein adversely affect sperm motility and survival.

METHOD OF STUDY

Spermatozoa obtained from normal fertile donors and washed free of seminal plasma were incubated with the medium (control), 1:2 and 1:100 dilutions of antitransferrin, 1:4, 1:8 and 1:100 dilutions of anti-alpha 2-HS glycoprotein, and a 1:2 dilution of antialbumin antiserum (negative control). Sperm motion characteristics in 10 microliters aliquots were evaluated at 30 min, 1 hr, 2 hr, 4 hr, and 24 hr using computerized sperm motion analysis. A paired t-test was done to analyze the effects of the various antibodies on sperm motion characteristics.

RESULTS

Antibodies to albumin failed to adversely affect sperm motility in general or the several sperm motion characteristics in particular. In contrast, antibodies to transferrin at the dilution of 1:2 adversely affected the percentage of motile and rapid spermatozoa, progressive and path velocities, straightness, linearity, track speed, and anterior-lateral head displacement (P < 0.001) at all the time intervals, whereas a 1:100 dilution of this antiserum adversely affected these parameters only at 24 hr. Elongation and beat cross-frequency were significantly affected at 4 and 24 hr by a 1:2 dilution of antitransferrin antiserum. The effects of anti-alpha 2-HS glycoprotein were more pronounced than those of antitransferrin, but they were similar. Dilutions of 1:4 and 1:8 were effective at all time intervals, whereas a 1:100 dilution was effective in reducing the track speed and the percentage of rapid cells at 24 hr (P < 0.001).

CONCLUSION

Antibodies to endometrial transferrin and alpha 2-HS glycoprotein present in the peritoneal fluid, and possibly in the oviductal fluid, of patients with endometriosis may adversely affect postcoital sperm motility and sperm survival.

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.

Epidemiology of endometriosis

This article summarizes present knowledge about the epidemiology of endometriosis. Surprisingly, little is known about the prevalence or risk factors of endometriosis, given the medical care and employment costs. Knowledge about the epidemiology of endometriosis is hampered by the inability to diagnose this disease in the general population. Based on a single cohort study, it is estimated that there is a 10% prevalence of endometriosis in the general population. Age is the only sociodemographic characteristic for which a consistent positive relationship has been observed. In general, the risk of endometriosis appears to increase for reproductive health factors that may relate to increased exposure to menstruation (i.e., shorter cycle length, longer duration of flow, or reduced parity). The risk appears to decrease for personal habits that may relate to decreased estrogen levels (i.e., smoking, exercise).

Increased monocyte chemotactic protein-1 level and activity in the peripheral blood of women with endometriosis. Le Groupe d'Investigation en Gynécologie

OBJECTIVE

Our purpose was to evaluate monocyte chemotactic protein-1 in the peripheral blood of women with and without endometriosis.

STUDY DESIGN

Fifty-seven patients with endometriosis at laparoscopy done for infertility and pelvic pain were compared with 44 fertile women with no evidence of endometriosis at tubal ligation by laparoscopy. Monocyte chemotactic protein-1 concentration in the plasma was determined by enzyme-linked immunosorbent assay and its biologic activity was evaluated by measuring monocyte chemotaxis with use of a human histiocytic cell line (U937).

RESULTS

Monocyte chemotactic protein-1 concentrations (median and range of values) found in the plasma were higher in patients with endometriosis (163, 0 to 788 pg/ml) than in normal controls (0, 0 to 355 pg/ml). This elevation was significant only in the minimal stage of endometriosis (revised American Fertility Society stage I). However, increased chemotactic activity (mean number of migrating cells/mm2 +/- SEM) was found in the stages I (1240 +/- 141), II (519 +/- 30), and III-IV (523 +/- 23) of the disease compared with normal controls (205 +/- 20). A total of 35% to 44% of this activity was inhibited in the presence of an antibody specific to monocyte chemotactic protein-1.

CONCLUSION

Endometriosis is associated with increased level and activity of monocyte chemotactic protein-1 in the peripheral blood. The elevation and activation of this cytokine could play a relevant role in the immunoinflammatory process associated with the disease.

Antibodies to endometrial transferrin and alpha 2-Heremans Schmidt (HS) glycoprotein in patients with endometriosis

PROBLEM

Identifying the endometrial antigens inciting autoimmunity is important in setting up an antibody assay for a non-invasive diagnosis and clinical monitoring of endometriosis.

METHODS

Two-dimensional gel electrophoresis of endometrial extracts, Western blot analysis, passive hemagglutination and enzyme-linked immunosorbent assay (ELISA), amino acid sequencing and molecular studies were done on chosen antigens. Forty-six women with endometriosis, 4 women with uterine leiomyomata, 4 with pelvic adhesions, 3 with repeat Cesarean sections (conditions that coexist with or predispose to endometriosis) and 46 controls participated.

RESULTS

Antigens with molecular weights (MW) of 64 kDa [isoelectric point (pI) of 3.5-4.0] and 72 kDa (pI of 4.5) bound to IgG in all patients with endometriosis, but not the controls. Amino acid sequencing of the proteins revealed that they had homology to alpha 2-Heremans Schmidt (HS) glycoprotein (MW: 64 kDa) and transferrin (MW: 72 kDa). Endometriosis patients had significant antibody levels to these two proteins (predictive value of 80-90%). The analysis of patients' endometrial RNA detected the message for alpha 2-HS glycoprotein and transferrin. Albumin (pI 5.5) and collagen (pI 3.5) failed to elicit antibody responses.

CONCLUSIONS

Patients with endometriosis have significant antibodies to endometrial transferrin and alpha 2-HS-glycoprotein. We can effectively use an antibody assay using these antigens for diagnosing endometriosis.

Target antigen(s) in endometrial autoimmunity of endometriosis

OBJECTIVE

To obtain the molecular weights (MW) of endometrial antigens eliciting immunoglobulin (Ig) G auto-antibodies in all endometriosis patients irrespective of their place of origin or race, and to verify their specificity and immunogenicity.

STUDY DESIGN AND RESULTS

We tested the serum and peritoneal fluid (P.F.) of 76 endometriosis patients and 24 controls from 4 cities against endometrial and implant antigens by Western blot analysis. Endometrial and implant antigens with MW of 34, 46/48, 64, 84, 94 and 120 kDa bound with IgG in serum and PF of most patients, but not the controls. Antigen(s) with MW of 64 kDa was reactive against serum or P.F. IgG of patients from all cities. Specificity: Endometrial and implant extracts did not react with monoclonal antibodies to WBC subsets and 5 sera with nuclear antibodies. Also, the presence of nuclear and endometrial antibodies did not correlate in 20 other patients with endometriosis. Immunogenicity: We immunized rabbits with the native and eluted (MW 29 to 68 kDa and > or = 68 kDa) endometrial and implant proteins. The antiserum had specific IgG binding to the same glandular epithelial antigens as those bound by the patient's serum.

CONCLUSIONS

Endometrial antigens with MW of 34, 46/48, 64, 94 and 120 kDa, especially 64 kDa appear to be specific, immunogenic and relevant to endometrial autoimmunity in all patients with endometriosis.

Immunosuppressive effect of danazol on lymphocyte-mediated cytotoxicity toward human endometrial stromal cells

The influence of danazol on the expression of lymphocyte-mediated cytotoxicity toward the stromal component of the endometrium was examined. Stromal cells were isolated from endometrial biopsy specimens of nine women without endometrial pathology and 12 patients with endometriosis. A cytotoxicity assay by 51Cr release was performed to determine the effect of danazol on natural killer lymphocyte lytic activity. A significant suppression of spontaneous cytotoxicity against stromal cell targets of both study subjects was observed when effectors were pretreated for 48 h with danazol at a concentration of 5 x 10(-6) mol/l. The time-course of the danazol effect indicated that drug activity was detectable as early as 24 h after the addition of the drug and increase up to 72 h. These findings confirm that danazol may influence the immune system at many levels. In particular, they demonstrate that the drug is also able to inhibit the natural immunity toward the stromal component of the endometrium.

Markers for endometriosis

Screening for endometriosis is subject to general rules. The two most important conditions, i.e. the disorder should be well-defined and serious, and there must be an effective way to treat or prevent it through screening, are not satisfied for endometriosis. Given the lack of understanding of the pathogenesis of this disease and the disreputable evidence of treatment effectiveness, other criteria for worthwhile screening programmes, such as prevalence, cost effectiveness and screening test performance, cannot be evaluated. Markers may be applied in the diagnostic process in the individual patient, although it should be realized that the best results will be obtained in patients with advanced disease, in whom routine pelvic examination will establish the diagnosis on purely clinical grounds anyway. The development of appropriate tissue markers may in the future shed more light on the intricate mechanisms involved in the pathogenesis of endometriosis.

Antiendometrial autoantibodies are generated in patients with endometriosis

PROBLEM

Our aim was to investigate endometrial antigens involved in the autoimmunity of endometriosis.

METHOD

We detected endometrial antigens against which autoantibodies directed with Western blotting.

RESULTS

Thirteen (72.2%), 14 (77.8%), and 15 (83.3%) of 18 serum samples from endometriosis patients had antibodies reactive against endometrial antigen wtih MW of 26 kd, 34 kd, and 42 kd, respectively, while 6 (33.3%), 8 (44.4%), and 8 (44.4%) of 18 samples from normal control women reacted against these antigens, respectively. The frequencies of antibodies to the endometrial antigens were significantly (P < 0.05) higher in the endometriosis patients than in the normal control women. Antibodies in peritoneal fluid (PF) reacted against antigens with MW of 26, 34, 38, 42, and 64 kd, while those from the normal control reacted against antigens with MW of 38, 42, and 64 kd. Serum samples from normal fertile males did not show any reactivity against these endometrial antigens.

CONCLUSIONS

Our results show that autoantibodies reactive against endometrial antigens are present in patients with endometriosis.

Glucocorticoid treatment decreases sera embryotoxicity in endometriosis patients

OBJECTIVE

To investigate the effect of short-term glucocorticoid administration on embryotoxicity of sera from infertile patients with mild to moderate endometriosis.

DESIGN

Prospective longitudinal study.

SETTING, PATIENTS

Eight infertile patients with mild to moderate endometriosis and a control group of eight infertile patients with tubal infertility were selected on the basis of laparoscopic examination.

INTERVENTIONS

Basal (B) serum collection and day 1 (T1), day 3 (T2), day 6 (T3), and day 12 (T4) serum drawn after a 3-day glucocorticoid treatment in endometriosis patients.

MAIN OUTCOME MEASURE

Embryotoxicity of endometriosis sera, before and after glucocorticoid treatment, was investigated using a bioassay performed on two-cell mouse embryos. Interleukin 1 alpha (IL-1 alpha) and antismooth muscle, antimitochondrial, and antinuclear autoantibodies were also tested in these sera.

RESULTS

At 50% concentration, endometriosis serum is embryotoxic in comparison with control; 0% versus 61% of the embryos reached the blastocyst stage at 72 hours, respectively (basal versus control, P less than 0.001). However, this embryotoxicity significantly decreases 12 days after glucocorticoid treatment in comparison with untreated sera; 32.4% versus 0% of the embryos reached blastocyst stage at 72 hours, respectively (T4 versus basal, P less than 0.001), although they did not reach nontoxic levels (greater than 50%). Interleukin 1 alpha was undetectable in all samples analyzed. In endometriosis sera, antismooth muscle antibody was detected.

CONCLUSIONS

At 50% concentration, serum from infertile patients with minimal to moderate endometriosis appears to be embryotoxic to the in vitro development of two-cell mouse embryos. However, this embryotoxicity significantly decreases 12 days after a 3-day treatment with glucocorticoids.