Endometrial pinopode and alphavbeta3 integrin expression is not impaired in infertile patients with endometriosis

The definition of unexplained infertility: A systematic review

BACKGROUND

There is no consensus on tests required to either diagnose unexplained infertility or use for research inclusion criteria. This leads to heterogeneity and bias affecting meta-analysis and best practice advice.

OBJECTIVES

This systematic review analyses the variability of inclusion criteria applied to couples with unexplained infertility. We propose standardised criteria for use both in future research studies and clinical diagnosis.

SEARCH STRATEGY

CINAHL and MEDLINE online databases were searched up to November 2022 for all published studies recruiting couples with unexplained infertility, available in full text in the English language.

DATA COLLECTION AND ANALYSIS

Data were collected in an Excel spreadsheet. Results were analysed per category and methodology or reference range.

MAIN RESULTS

Of 375 relevant studies, only 258 defined their inclusion criteria. The most commonly applied inclusion criteria were semen analysis, tubal patency and assessment of ovulation in 220 (85%), 232 (90%), 205 (79.5%) respectively. Only 87/220 (39.5%) studies reporting semen analysis used the World Health Organization (WHO) limits. Tubal patency was accepted if bilateral in 145/232 (62.5%) and if unilateral in 24/232 (10.3%). Ovulation was assessed using mid-luteal serum progesterone in 115/205 (56.1%) and by a history of regular cycles in 87/205 (42.4%). Other criteria, including uterine cavity assessment and hormone profile, were applied in less than 50% of included studies.

CONCLUSIONS

This review highlights the heterogeneity among studied populations with unexplained infertility. Development and application of internationally accepted criteria will improve the quality of research and future clinical care.

Luteal Phase in Assisted Reproductive Technology

Luteal phase (LP) is the period of time beginning shortly after ovulation and ending either with luteolysis, shortly before menstrual bleeding, or with the establishment of pregnancy. During the LP, the corpus luteum (CL) secretes progesterone and some other hormones that are essential to prepare the uterus for implantation and further development of the embryo, the function known as uterine receptivity. LP deficiency (LPD) can occur when the secretory activity of the CL is deficient, but also in cases of normal CL function, where it is caused by a defective endometrial response to normal levels of progesterone. LPD is particularly frequent in treatments using assisted reproductive technology (ART). Controlled ovarian stimulation usually aims to obtain the highest number possible of good-quality oocytes and requires the use of gonadotropin-releasing hormone (GnRH) analogs, to prevent premature ovulation, as well as an ovulation trigger to achieve timed final oocyte maturation. Altogether, these treatments suppress pituitary secretion of luteinizing hormone (LH), required for the formation and early activity of the CL. In addition to problems of endometrial receptivity for embryos, LPD also leads to dysfunction of the local uterine immune system, with an increased risk of embryo rejection, abnormally high uterine contractility, and restriction of uterine blood flow. There are two alternatives of LPD prevention: a direct administration of exogenous progesterone to restore the physiological progesterone serum concentration independently of the CL function, on the one hand, and treatments aimed to stimulate the CL activity so as to increase endogenous progesterone production, on the other hand. In case of pregnancy, some kind of LP support is often needed until the luteal-placental shift occurs. If LPD is caused by defective response of the endometrium and uterine immune cells to normal concentrations of progesterone, a still poorly defined condition, symptomatic treatments are the only available solution currently available.

Evidence from three cohort studies on the expression of MUC16 around the time of implantation suggests it is an inhibitor of implantation

PURPOSE

To examine the expression of MUC16 in the endometrium peri-implantation period in three different cohort studies.

METHODS

This was a retrospective observational cohort study. A total of 245 participants were recruited in three separate cohort studies: (1) women with recurrent miscarriage (n = 50) and fertile controls (n = 29); (2) women who had high (n = 20) or normal (n = 20) progesterone on the day of hCG trigger in ovarian stimulation cycle for IVF; and (3) women who did (n = 95) or did not (n = 31) conceive following frozen embryo transfer in HRT cycles. All subjects had archived endometrial samples precisely taken on LH+7 in natural cycles, or hCG+6 in ovarian stimulation cycles, or P+5 in HRT cycles. The H-score (median, range) of MUC16 in the luminal epithelium and glandular epithelium was determined by using immunohistochemistry.

RESULTS

The median (range) of H-score of MUC16 in the luminal epithelium (1) in women with recurrent pregnancy loss was 23.7 (0-300), which was significantly (P < 0.05) lower than that of 118.4 (7.7-300) in fertile controls; (2) in women with elevated progesterone on the day of hCG administration (147.8, 18.0-230.1), significantly (P < 0.05) higher than that of women with normal progesterone (61.0, 2.3-205.3); (3) in women who conceived (23.1, 0-250.3), significantly (P < 0.001) lower than that in women who did not conceive (58.4, 0-300).

CONCLUSION

The expression of MUC16 in all three cohort studies is consistent with it being an inhibitor of implantation.

Ethiopathogenic mechanisms of endometriosis-related infertility

Endometriosis is a highly prevalent disease among women of reproductive age and is frequently associated to infertility. However, the mechanisms underlying endometriosis-related infertility are still not completely known. Several studies have been conducted in order to elucidate this question. Besides anatomical changes that may impair gametes and embryo transport along the tubes; a smaller ovarian reserve due to advanced endometriosis and endometriomas; and a dysregulated hypothalamic-pituitary-ovarian axis, there are pieces of evidence suggesting that the peritoneal ectopic endometrial foci may induce a local inflammatory response, with the recruitment of macrophages, cytokine release, and reactive oxygen species generation, leading to a pro-oxidant peritoneal microenvironment. These alterations may be systemically reflected and also affect the follicular microenvironment. A harmful follicular fluid may disrupt cumulus cells functions and, consequently, compromise oocyte competence. There is also evidence suggesting that the peritoneal fluid of women with endometriosis may alter sperm function. Reduced endometrial receptivity is also pointed as a possible mechanism involved in endometriosis-related infertility, which needs further investigation.

Alterations in expression of endometrial milk fat globule-EGF factor 8 (MFG-E8) and leukemia inhibitory factor (LIF) in patients with infertility and endometriosis

OBJECTIVE

The aim of this study was to compare the endometrial expression of milk fat globule-EGF factor 8 (MFG-E8), its receptor integrin αvβ3, and leukemia inhibitory factor (LIF) in patients with endometriosis and infertility and in healthy fertile patients during the window of implantation.

METHODS

Five patients with peritoneal endometriosis and infertility (case group) and four healthy fertile patients (control group) were recruited. All patients were either diagnosed with or ruled out for endometriosis by laparoscopic surgery; the case group underwent surgery for infertility investigation and the control group for tubal ligation. Endometrial biopsies were performed in all patients during the window of implantation (LH+8 to LH+10), and then the samples were analyzed by immunochemistry for MFG-E8, integrin αvβ3, and LIF.

RESULTS

In patients with endometriosis and infertility, expression of MFG-E8 was significantly increased in the glandular epithelium when compared to healthy fertile patients (p<0.001). Moreover, LIF expression was lower in patients with endometriosis and infertility (p<0.05). Nevertheless, we found no difference in integrin αvβ3 expression between the groups (p=0.084).

CONCLUSION

This study showed for the first time that MFG-E8 expression is impaired in the endometrium of patients with endometriosis and infertility during the window of implantation. Moreover, LIF is also diminished in the endometrium of these patients as shown before.

Expression of PGR, HBEGF, ITGAV, ITGB3 and SPP1 genes in eutopic endometrium of infertile women with endometriosis during the implantation window: a pilot study

OBJECTIVE

Alterations in endometrial receptivity may be involved in the etiopathogenesis of endometriosis-related infertility. The literature has suggested that patients with endometriosis present progestin resistance, which could affect embryo implantation. We question the presence of alterations in the expression of the progesterone receptor gene (PGR) and the genes related to endometrium-embryo interaction regulated by progesterone. This pilot study compared the expression of PGR, HBEGF, ITGAV, ITGB3, and SPP1 genes in eutopic endometrium during the implantation window (IW) in infertile women with endometriosis with that observed in the endometrium of fertile and infertile controls.

METHODS

In this prospective case-control study, endometrial biopsies were performed during the IW in patients aged between 18 and 45 years old, with regular cycles and without endocrine/systemic dysfunctions, divided into endometriosis (END), infertile control (IC) and fertile control (FC) groups. Total RNA extraction, cDNA synthesis, and gene expression analysis by Real-Time PCR were performed. We assessed the size of the difference that our series was powered to detect.

RESULTS

From the 687 patients who underwent diagnostic videolaparoscopy or tubal ligation at the University Hospital, 130 were eligible. Of these, 32 had endometrial samples collected, with 17 confirmed in the IW. Fifteen samples (5 END, 5 IC and 5 FC) were analyzed. There was no significant difference in the expression of any studied gene. Our sample size allowed us to identify or discard large differences (two standard deviations) among the groups.

CONCLUSION

Endometriosis doesn't cause large changes in the endometrial expression of PGR, HBEGF, ITGAV, ITGB3 and SPP1 during the IW.

GnRH agonist administration prior to embryo transfer in freeze-all cycles of patients with endometriosis or aberrant endometrial integrin expression

Prolonged gonadotrophin-releasing hormone agonist (GnRHa) administration before IVF with fresh embryo transfer to patients with endometriosis or aberrant endometrial integrin expression (-integrin) improves outcomes but may suppress ovarian response and prevents elective cryopreservation of all embryos. This retrospective cohort pilot study evaluates freeze-all cycles with subsequent prolonged GnRHa before embryo transfer in these populations. Patients from 2010 to 2015 who met inclusion criteria and received a long-acting GnRHa every 28 days twice before FET were evaluated. A subset underwent comprehensive chromosomal screening (CCS) after trophectoderm biopsy. Three groups were identified: Group 1: + CCS, +endometriosis (20 patients, 20 transfers); Group 2: +CCS, -integrin (12 patients, 13 transfers); Group 3: no CCS, +endometriosis or -integrin (10 patients, 12 transfers); Group 4: all transfers after CCS for descriptive comparison only (n = 2809). Baseline characteristics were similar among Groups 1-3 except that the mean surgery to oocyte aspiration interval was longer for Group 1 than Group 3. Implantation and ongoing pregnancy rates were statistically similar among the three groups and compared favourably to Group 4. A non-significant trend towards improved outcomes was noted in Group 1. Prolonged GnRHa after freeze-all in these patients avoids excessive ovarian suppression and results in excellent outcomes.

What is the contribution of embryo-endometrial asynchrony to implantation failure?

PURPOSE

The synchronized development of a viable embryo and a receptive endometrium is critical for successful implantation to take place. The aim of this paper is to review current thinking about the importance of embryo-endometrial synchrony in in vitro fertilization (IVF).

METHODS

Detailed review of the literature on embryo-endometrial synchrony.

RESULTS

By convention, the time when the blastocyst first attaches and starts to invade into the endometrium has been defined as the 'window of implantation'. The term window of implantation can be misleading when it is used to imply that there is a single critical window in time that determines whether implantation will be successful or not. Embryo maturation and endometrial development are two independent continuous processes. Implantation occurs when the two tissues fuse and pregnancy is established. A key concept in understanding this event is developmental 'synchrony', defined as when the early embryo and the uterus are both developing at the same rate such that they will be ready to commence and successfully continue implantation at the same time. Many different events, including controlled ovarian hyperstimulation as routinely used in IVF, can potentially disrupt embryo-endometrial synchrony. There is some evidence in humans that implantation rates are significantly reduced when embryo-endometrial development asynchrony is greater than 3 days (±1.5 days).

CONCLUSIONS

Embryo-endometrial synchrony is critical for successful implantation. There is an unmet need for improved precision in the evaluation of endometrial development to permit better synchronization of the embryo and the endometrium prior to implantation.

Endometrial biomarkers for the non-invasive diagnosis of endometriosis

BACKGROUND

About 10% of reproductive-aged women suffer from endometriosis, which is a costly, chronic disease that causes pelvic pain and subfertility. Laparoscopy is the gold standard diagnostic test for endometriosis, but it is expensive and carries surgical risks. Currently, there are no non-invasive tests available in clinical practice that accurately diagnose endometriosis. This is the first diagnostic test accuracy review of endometrial biomarkers for endometriosis that utilises Cochrane methodologies, providing an update on the rapidly expanding literature in this field.

OBJECTIVES

To determine the diagnostic accuracy of the endometrial biomarkers for pelvic endometriosis, using a surgical diagnosis as the reference standard. We evaluated the tests as replacement tests for diagnostic surgery and as triage tests to inform decisions to undertake surgery for endometriosis.

SEARCH METHODS

We did not restrict the searches to particular study designs, language or publication dates. To identify trials, we searched the following databases: CENTRAL (2015, July), MEDLINE (inception to May 2015), EMBASE (inception to May 2015), CINAHL (inception to April 2015), PsycINFO (inception to April 2015), Web of Science (inception to April 2015), LILACS (inception to April 2015), OAIster (inception to April 2015), TRIP (inception to April 2015) and ClinicalTrials.gov (inception to April 2015). We searched DARE and PubMed databases up to April 2015 to identify reviews and guidelines as sources of references to potentially relevant studies. We also performed searches for papers recently published and not yet indexed in the major databases. The search strategies incorporated words in the title, abstract, text words across the record and the medical subject headings (MeSH).

SELECTION CRITERIA

We considered published peer-reviewed, randomised controlled or cross-sectional studies of any size that included 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).

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data from each study and performed a quality assessment. For each endometrial diagnostic test, we classified the data as positive or negative for the surgical detection of endometriosis and calculated the estimates of sensitivity and specificity. We considered two or more tests evaluated in the same cohort as separate data sets. We used the bivariate model to obtain pooled estimates of sensitivity and specificity whenever sufficient data were available. The predetermined criteria for a clinically useful test to replace diagnostic surgery was one with a sensitivity of 94% and a specificity of 79%. The criteria for triage tests were set at sensitivity at or above 95% and specificity at or above 50%, which in case of negative results rules out the diagnosis (SnOUT test) or sensitivity at or above 50% with specificity at or above 95%, which in case of positive result rules in the diagnosis (SpIN test).

MAIN RESULTS

We included 54 studies involving 2729 participants, most of which were of poor methodological quality. The studies evaluated endometrial biomarkers either in specific phases of the menstrual cycle or outside of it, and the studies tested the biomarkers either in menstrual fluid, in whole endometrial tissue or in separate endometrial components. Twenty-seven studies evaluated the diagnostic performance of 22 endometrial biomarkers for endometriosis. These were angiogenesis and growth factors (PROK-1), cell-adhesion molecules (integrins α3β1, α4β1, β1 and α6), DNA-repair molecules (hTERT), endometrial and mitochondrial proteome, hormonal markers (CYP19, 17βHSD2, ER-α, ER-β), inflammatory markers (IL-1R2), myogenic markers (caldesmon, CALD-1), neural markers (PGP 9.5, VIP, CGRP, SP, NPY, NF) and tumour markers (CA-125). Most of these biomarkers were assessed in single studies, whilst only data for PGP 9.5 and CYP19 were available for meta-analysis. These two biomarkers demonstrated significant diversity for the diagnostic estimates between the studies; however, the data were too limited to reliably determine the sources of heterogeneity. The mean sensitivities and specificities of PGP 9.5 (7 studies, 361 women) were 0.96 (95% confidence interval (CI) 0.91 to 1.00) and 0.86 (95% CI 0.70 to 1.00), after excluding one outlier study, and for CYP19 (8 studies, 444 women), they were were 0.77 (95% CI 0.70 to 0.85) and 0.74 (95% CI 0.65 to 84), respectively. We could not statistically evaluate other biomarkers in a meaningful way. An additional 31 studies evaluated 77 biomarkers that showed no evidence of differences in expression levels between the groups of women with and without endometriosis.

AUTHORS' CONCLUSIONS

We could not statistically evaluate most of the biomarkers assessed in this review in a meaningful way. In view of the low quality of most of the included studies, the findings of this review should be interpreted with caution. Although PGP 9.5 met the criteria for a replacement test, it demonstrated considerable inter study heterogeneity in diagnostic estimates, the source of which could not be determined. Several endometrial biomarkers, such as endometrial proteome, 17βHSD2, IL-1R2, caldesmon and other neural markers (VIP, CGRP, SP, NPY and combination of VIP, PGP 9.5 and SP) showed promising evidence of diagnostic accuracy, but there was insufficient or poor quality evidence for any clinical recommendations. Laparoscopy remains the gold standard for the diagnosis of endometriosis, and using any non-invasive tests should only be undertaken in a research setting. We have also identified a number of biomarkers that demonstrated no diagnostic value for endometriosis. We recommend that researchers direct future studies towards biomarkers with high diagnostic potential in good quality diagnostic studies.

MicroRNA-31 is significantly elevated in both human endometrium and serum during the window of implantation: a potential biomarker for optimum receptivity

The window of implantation of human embryos into the endometrium spans Cycle Days 20-24 of the 28-day menstrual cycle. However, uterine receptivity may not be reliably replicated in infertile patients throughout this span. Thus, it is of importance to be able to determine optimal receptivity through a minimally invasive measure. We screened expression of a number of candidate micro-RNAs (miRNAs) in endometrial tissues and serum collected from a panel of fertile women during both the proliferative phase and the secretory phase of a normal menstrual cycle. We found that several miRNAs were significantly elevated in endometrial tissues in the secretory phase versus the proliferative phase. One of these, miR-31, was found to be not only detectable in serum samples but also significantly elevated in the secretory phase versus the proliferative phase. MiR-31 is known to target several immunomodulatory factors, such as FOXP3 and CXCL12. We find that both of these factors are significantly downregulated in endometrial tissues during the secretory phase. Our data suggest that miR-31 is a potential biomarker for optimal endometrial receptivity, possibly operating through an immunosuppressive mechanism.

Effects of galectin-3 inhibition on endometrial cell cycle and adhesion

Galectin-3 (gal-3) and its ligands have been implicated in cell transformation and cancer metastasis. Gal-3 protein has been found in uterine epithelial cells adjacent to implanting blastocysts in different cell types. In order to investigate the role of gal-3 in the establishment of human endometrial receptivity, the expression of gal-3 in human endometrial cell line RL95-2 was silenced by RNA interference technology using gal-3 specific small RNA. The expression of gal-3 was detected by the reverse transcriptase-polymerase chain reaction and Western blot analysis. After the suppression of gal-3, cell cycle changes and the expression of integrin β1 were detected by flow cytometry. The adhesive ability of RL95-2 cells was analyzed by the adhesion test. Gal-3 siRNA transfection efficiency reached 70%-90%. The expression of gal-3 mRNA and protein in RL95-2 cells was strongly inhibited by 70%-90% after RNA interference. Inhibition of gal-3 expression decreased S-phase but increased G1 phase cells. Integrin β1 expression was down-regulated, and the adhesive ability of RL95-2 cells to fibronectin (FN) was significantly reduced. Gal-3 may be involved in the establishment of endometrial receptivity by regulating the proliferation and adhesion of endometrial cells. The influence on adhesion may be related with the integrin modulation.

Characterization of periostin expression in human endometrium and endometriotic lesions

OBJECTIVE(S)

To investigate the expression of periostin in the eutopic and ectopic endometrium of women diagnosed as endometriosis and evaluate the role of periostin in the pathogenesis of endometriosis.

STUDY DESIGN

In this study, the expression of periostin was evaluated in the endometrial specimens from 35 women diagnosed as endometriosis and from 30 healthy women. To assess the presence and localization of periostin throughout the menstrual cycle in both eutopic and ectopic endometrium of women with endometriosis, microscopic evaluation was conducted. It was also subsequently compared with normal endometrium.

RESULTS

In the eutopic and ectopic endometrium of women with endometriosis, immunoreactivities of periostin increased compared with those of normal endometrium. We also observed a cyclic variation in the eutopic stromal periostin immunoreactivity throughout their menstrual cycle because higher H score values were observed in the proliferative phase than those in the secretory phase.

CONCLUSION(S)

These findings indicated that periostin may be involved in the pathophysiology of endometriosis.

Expression pattern of osteopontin and αvβ3 integrin during the implantation window in infertile patients with early stages of endometriosis

BACKGROUND

To study endometrial receptivity in terms of osteopontin (OPN) and αvβ3 integrin expression and co-expression in infertile women with early stages of endometriosis.

METHODS

We investigated the immunohistochemical expression and co-expression of OPN and αvβ3 integrin in the endometrium of 20 infertile patients with Stage I or II endometriosis as the only detectable cause of infertility, 20 infertile patients with unexplained infertility and 20 fertile women undergoing tubal sterilization. Two endometrial biopsies were performed during a single menstrual cycle (postovulatory Day +7 to +8 and 4 days later) in each subject.

RESULTS

No statistically significant differences regarding OPN and αvβ3 integrin expression were found between infertile patients with endometriosis and the two control groups. There was no significant correlation between OPN and αvβ3 integrin staining intensity in the mid-luteal phase biopsies in any of the groups studied.

CONCLUSIONS

Endometrial OPN and αvβ3 integrin expression or co-expression is not impaired during the window of implantation in patients with Stage I-II endometriosis. Further studies are needed to determine whether these results imply normal endometrial receptivity in such patients or add to the increasing uncertainty about the clinical value of assessing the endometrium with these markers of implantation.

Osteopontin and alphavbeta3 integrin expression in the endometrium of infertile and fertile women

Osteopontin and its receptor alpha(v)beta(3) integrin have recently been proposed as a major complex to promote embryo attachment, and thus they would be useful as markers of endometrial receptivity. In the current study alpha(v)beta(3) integrin and osteopontin expression and co-expression in in-phase and out-of-phase endometrial biopsies from normal healthy women (n = 12) and infertile patients (n = 107) were investigated. Two endometrial biopsies (post-ovulatory day +6 to +8, and 4 days later) were performed during a single menstrual cycle in each subject. Oestradiol and progesterone serum concentrations were quantified on the same days as endometrial sampling. No statistically significant difference regarding alpha(v)beta(3) integrin and osteopontin expression and their coexpression was found between fertile controls and infertile patients irrespective of endometria being in-phase or out-of-phase, infertility factors detected or whether patients became spontaneously pregnant or not. Although a co-ordinate high concentration of both glycoproteins on post-ovulatory day 8 onwards was observed, there was an evident lack of temporal co-expression of these markers during the implantation window. It is concluded that the functional significance of the osteopontin:alpha(v)beta(3) integrin complex as a marker of endometrial receptivity and implantation potential in women seems to be untenable.

The incidence of aberrant endometrial alphavbeta(3) vitronectin expression in a high risk infertility population: could prolonged GnRH agonist therapy play a role?

PURPOSE

Evaluate the incidence of aberrant endometrial integrin (alphavbeta(3) vitronectin) expression in patients at high risk for implantation defects.

MATERIALS AND METHODS

Retrospective case-control trial of 74 consecutive infertile patients with prior failed IVF cycles despite good embryo quality and/or endometriosis who underwent endometrial biopsy 9-11 days after an LH surge to assess the presence or absence of alphavbeta(3) vitronectin. Patients were separated into two groups for analysis based on the presence (Gr. A) or absence (Gr. B) of integrin expression. A subset of Gr. B patients (86.1%) was treated with a 2 month course of a GnRH agonist prior to IVF (Gr. B1). No Gr. A patients were so treated.

RESULTS

Absent alphavbeta(3) vitronectin expression was noted in 48.6% of patients evaluated. A trend towards more severe endometriosis was noted in Gr. B (57.1 vs 31.5%). Responses to controlled ovarian hyperstimulation and IVF cycle outcomes including ongoing pregnancy rates were similar between Gr. B1 patients untreated Gr. A controls (55.6 vs 63.9%).

CONCLUSIONS

A high incidence of absent endometrial alphavbeta(3) vitronectin expression is noted in patients at increased risk for implantation defects. Prolonged GnRH agonist therapy prior to an IVF cycle resulted in outcomes similar to untreated controls with positive expression.

Combination of 17β-estradiol with the environmental pollutant TCDD is involved in pathogenesis of endometriosis via up-regulating the chemokine I-309–CCR8

OBJECTIVE

To explore the effects of the combined E(2) with the environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on CCR8-I-309 expression by the endometriotic lesion-associated cells in the pathogenesis of endometriosis.

DESIGN

Prospective laboratory study.

SETTING

University hospital.

PATIENT(S)

Chinese women with endometriosis.

INTERVENTION(S)

The endometriotic tissue and matched eutopic endometrium were collected. Endometrial stromal cells (ESCs), HPMC, and U937 cells were treated with 17beta-E(2) or TCDD. The ESCs were stimulated with I-309.

MAIN OUTCOME MEASURE(S)

The expression of CCR8 in tissues was analyzed by reverse transcription-polymerase chain reaction and immunohistochemistry. The effect of I-309 on integrin beta1 and alphavbeta3 expression intensity was analyzed by flow cytometry, and the chemotactic activity of I-309 on the ESC was explored by chemotactic assay. Concentration of I-309 in the culture supernatant was quantified by enzyme-linked immunosorbent assay.

RESULT(S)

CCR8 was overexpressed in the endometriotic tissue. I-309 promoted the expression of integrin beta1. Estradiol and TCDD up-regulated CCR8 expression by ESCs. Estradiol magnified the stimulatory effect of TCDD on I-309 secretion by U937. The interaction of HPMC and U937 cells promoted I-309 secretion.

CONCLUSION(S)

These findings imply that the combination of 17beta-E(2) with the environmental pollutant TCDD is involved in the pathogenesis of endometriosis via up-regulating the chemokine CCR8-I-309.

The presence of pinopodes in the human endometrium does not delineate the implantation window

OBJECTIVE

To assess pinopode formation in human endometrium during the luteal phase of the menstrual cycle and in the first trimester of pregnancy.

DESIGN

Prospective clinical study.

SETTING

Outpatient infertility clinics and outpatient family planning clinic.

PATIENT(S)

Thirty-two regularly cycling infertile women, 15 regularly cycling fertile women, 9 women receiving elective termination of pregnancy, and 1 woman receiving GnRH agonist and hormone therapy addback.

INTERVENTION(S)

Endometrial tissue was collected by suction pipelle and examined by scanning electron microscopy for pinopode formation.

MAIN OUTCOME MEASURE(S)

Endometrial tissue was scored (0, 1, 2, 3, or 4) depending on the percentage of the surface covered in pinopodes (from 0% to >20% of 100 fields).

RESULT(S)

Pinopodes were present throughout the luteal phase of the menstrual cycle, up to the 11th week of pregnancy, and in the endometrium of the woman on GnRH agonist and hormone therapy.

CONCLUSION(S)

Pinopodes can be detected in the progesterone-exposed endometrium for an extended period of time, in contradistinction to the perception that they are markers for the implantation window in the human endometrium.

Leukaemia inhibitory factor and interleukin 11 levels in uterine flushings of infertile patients with endometriosis

BACKGROUND

Exact aetiology of infertility in stage I/II endometriosis patients is not known. Interleukin 11 (IL-11) and leukaemia-inhibitory factor (LIF) are factors associated with implantation window in human eutopic endometrium. We decided to test whether there is an altered secretion of these factors, which could explain receptivity defect in patients with minimal endometriosis.

METHODS

Uterine flushing and endometrial samples were collected 7-9 days after ovulation (implantation window) from infertile patients with stage I/II endometriosis (n = 14) and fertile, endometriosis-free controls (n = 21). IL-11 and LIF were assessed in uterine flushings in eutopic endometria in all patients by enzyme-linked immunosorbent assay (ELISA). In eutopic endometrium, semiquantitative RT-PCR was performed for LIF and IL-11 mRNA expressions.

RESULTS

No statistically significant differences were found in uterine flushing in women with and without endometriosis with regard to IL-11 levels (0.0 pg/ml versus 0.0 pg/ml) and LIF (25.53 pg/ml versus 36.26 pg/ml). These results were confirmed by the results of RT-PCR, where there were also no differences between studied groups.

CONCLUSIONS

There is no receptivity defect with regard to LIF and IL-11 secretions by eutopic endometrium in infertile women with endometriosis.