SARS-CoV-2 is not found in human semen during mild COVID-19 acute stage.

The aim of this study was to verify the presence of SARS-CoV-2 in the seminal sample of men during the acute phase of COVID-19. A prospective study was performed with inclusion of twenty-two men diagnosed with COVID-19 through RT-PCR from pharyngeal smear samples and who were in the acute phase of infection. These men were evaluated regarding medical history and physical examination. Furthermore, seminal samples of each men were collected 7, 14 and 21 days after the infection was confirmed. The sample were used for seminal analysis, as well as for the presence of SARS-CoV-2 using RT-PCR technique. In addition, cell culture was performed with subsequent repetition of the analysis of viral presence. None of the semen samples collected was positive for the detection of the virus that causes COVID-19. Most of the men evaluated had a mild condition and the loss of smell was the most frequent symptom. There were no significant changes in seminal parameters within the period of study. Based on our pilot data, patients with a mild form of COVID-19 in the acute stage of the disease are unlikely to have SARS-CoV-2 in semen.

Risks of nonchromosomal birth defects, small-for-gestational age birthweight, and prematurity with in vitro fertilization: effect of number of embryos transferred and plurality at conception versus at birth.

PURPOSE: Excess embryos transferred (ET) (> plurality at birth) and fetal heartbeats (FHB) at 6 weeks' gestation are associated with reductions in birthweight and gestation, but prior studies have been limited by small sample sizes and limited IVF data. This analysis evaluated associations between excess ET, excess FHB, and adverse perinatal outcomes, including the risk of nonchromosomal birth defects. METHODS: Live births conceived via IVF from Massachusetts, New York, North Carolina, and Texas included 138,435 children born 2004-2013 (Texas), 2004-2016 (Massachusetts and North Carolina), and 2004-2017 (New York) were classified by ET and FHB. Major birth defects were reported by statewide registries within the first year of life. Logistic regression was used to estimate adjusted odds ratios (AORs) and 95% CIs of the risks of a major nonchromosomal birth defect, small-for-gestational age birthweight (SGA), low birthweight (LBW), and preterm birth (≤36 weeks), by excess ET, and excess ET + excess FHB, by plurality at birth (singletons and twins). RESULTS: In singletons with [2 ET, FHB =1] and [≥3 ET, FHB=1], risks [AOR (95% CI)] were increased, respectively, for major nonchromosomal birth defects [1.13 (1.00-1.27) and 1.18 (1.00-1.38)], SGA [1.10 (1.03-1.17) and 1.15 (1.05-1.26)], LBW [1.09 (1.02-1.13) and 1.17 (1.07-1.27)], and preterm birth [1.06 (1.00-1.12) and 1.14 (1.06-1.23)]. With excess ET + excess FHB, risks of all adverse outcomes except major nonchromosomal birth defects increased further for both singletons and twins. CONCLUSION: Excess embryos transferred are associated with increased risks for nonchromosomal birth defects, reduced birthweight, and prematurity in IVF-conceived births.

The risk of birth defects with conception by ART.

STUDY QUESTION: What is the association between ART conception and treatment parameters and the risk of birth defects? SUMMARY ANSWER: Compared to naturally conceived singleton infants, the risk of a major nonchromosomal defect among ART singletons conceived with autologous oocytes and fresh embryos without use of ICSI was increased by 18%, with increases of 42% and 30% for use of ICSI with and without male factor diagnosis, respectively. WHAT IS KNOWN ALREADY: Prior studies have indicated that infertility and ART are associated with an increased risk of birth defects but have been limited by small sample size and inadequate statistical power, failure to differentiate results by plurality, differences in birth defect definitions and methods of ascertainment, lack of information on ART treatment parameters or study periods spanning decades resulting in a substantial historical bias as ART techniques have improved. STUDY DESIGN, SIZE, DURATION: This was a population-based cohort study linking ART cycles reported to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) from 1 January 2004 to 31 December 2015 that resulted in live births from 1 September 2004 to 31 December 2016 in Massachusetts and North Carolina and from 1 September 2004 to 31 December 2015 for Texas and New York: these were large and ethnically diverse States, with birth defect registries utilizing the same case definitions and data collected, and with high numbers of ART births annually. A 10:1 sample of non-ART births were chosen within the same time period as the ART birth. Naturally conceived ART siblings were identified through the mother's information. Non-ART children were classified as being born to women who conceived with ovulation induction (OI)/IUI when there was an indication of infertility treatment on the birth certificate, but the woman did not link to the SART CORS; all others were classified as being naturally conceived. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study population included 135 051 ART children (78 362 singletons and 56 689 twins), 23 647 naturally conceived ART siblings (22 301 singletons and 1346 twins) and 9396 children born to women treated with OI/IUI (6597 singletons and 2799 twins) and 1 067 922 naturally conceived children (1 037 757 singletons and 30 165 twins). All study children were linked to their respective State birth defect registries to identify major defects diagnosed within the first year of life. We classified children with major defects as either chromosomal (i.e. presence of a chromosomal defect with or without any other major defect) or nonchromosomal (i.e. presence of a major defect but having no chromosomal defect), or all major defects (chromosomal and nonchromosomal). Logistic regression models were used to generate adjusted odds ratios (AORs) and 95% CI to evaluate the risk of birth defects due to conception with ART (using autologous oocytes and fresh embryos), and with and without the use of ICSI in the absence or presence of male factor infertility, with naturally conceived children as the reference. Analyses within the ART group were stratified by combinations of oocyte source (autologous, donor) and embryo state (fresh, thawed), with births from autologous oocytes and fresh embryos as the reference. Analyses limited to fresh embryos were stratified by oocyte source (autologous, donor) and the use of ICSI. Triplets and higher-order multiples were excluded. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 21 998 singleton children (1.9%) and 3037 twin children (3.3%) had a major birth defect. Compared to naturally conceived children, ART singletons (conceived from autologous oocytes, fresh embryos without the use of ICSI) had increased risks of a major nonchromosomal birth defect (AOR 1.18, 95% 1.05, 1.32), cardiovascular defects (AOR 1.20, 95% CI 1.03, 1.40), and any birth defect (AOR 1.18, 95% CI 1.09, 1.27). Compared to naturally conceived children, ART singletons conceived (from autologous oocytes, fresh embryos) with the use of ICSI, the risks were increased for a major nonchromosomal birth defect (AOR 1.30, 95% CI 1.16, 1.45 without male factor diagnosis; AOR 1.42, 95% CI 1.28, 1.57 with male factor diagnosis); blastogenesis defects (AOR 1.49, 95% CI 1.08, 2.05 without male factor; AOR 1.56, 95% CI 1.17, 2.08 with male factor); cardiovascular defects (AOR 1.28, 95% CI 1.10,1.48 without male factor; AOR 1.45, 95% CI 1.27, 1.66 with male factor); in addition, the risk for musculoskeletal defects was increased (AOR 1.34, 95% CI 1.01, 1.78 without male factor) and the risk for genitourinary defects in male infants was increased (AOR 1.33, 95% CI 1.08, 1.65 with male factor). Comparisons within ART singleton births conceived from autologous oocytes and fresh embryos indicated that the use of ICSI was associated with increased risks of a major nonchromosomal birth defect (AOR 1.18, 95% CI 1.03, 1.35), blastogenesis defects (AOR 1.65, 95% CI 1.08, 2.51), gastrointestinal defects (AOR 2.21, 95% CI 1.28, 3.82) and any defect (AOR 1.11, 95% CI 1.01, 1.22). Compared to naturally conceived children, ART singleton siblings had increased risks of musculoskeletal defects (AOR 1.32, 95% CI 1.04, 1.67) and any defect (AOR 1.15, 95% CI 1.08, 1.23). ART twins (conceived with autologous oocytes, fresh embryos, without ICSI) were at increased risk of chromosomal defects (AOR 1.89, 95% CI 1.10, 3.24) and ART twin siblings were at increased risk of any defect (AOR 1.26, 95% CI 1.01, 1.57). The 18% increased risk of a major nonchromosomal birth defect in singleton infants conceived with ART without ICSI (∼36% of ART births), the 30% increased risk with ICSI without male factor (∼33% of ART births), and the 42% increased risk with ICSI and male factor (∼31% of ART births) translates into an estimated excess of 386 major birth defects among the 68 908 singleton children born by ART in 2017. LIMITATIONS, REASONS FOR CAUTION: In the SART CORS database, it was not possible to differentiate method of embryo freezing (slow freezing vs vitrification), and data on ICSI was only available in the fresh embryo ART group. In the OI/IUI group, it was not possible to differentiate type of non-ART treatment utilized, and in both the ART and OI/IUI groups, data were unavailable on duration of infertility. WIDER IMPLICATIONS OF THE FINDINGS: The use of ART is associated with increased risks of a major nonchromosomal birth defect, cardiovascular defect and any defect in singleton children, and chromosomal defects in twins; the use of ICSI further increases this risk, the most with male factor infertility. These findings support the judicious use of ICSI only when medically indicated. The relative contribution of ART treatment parameters versus the biology of the subfertile couple to this increased risk remains unclear and warrants further study. STUDY FUNDING/COMPETING INTEREST(S): This project was supported by grant R01 HD084377 from the National Institute of Child Health and Human Development. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Child Health and Human Development, or the National Institutes of Health, nor any of the State Departments of Health which contributed data. E.W. is a contract vendor for SART; all other authors report no conflicts. TRIAL REGISTRATION NUMBER: N/A.

Assessment of Birth Defects and Cancer Risk in Children Conceived via In Vitro Fertilization in the US.

Importance: Children with birth defects have a greater risk of developing cancer, but this association has not yet been evaluated in children conceived with in vitro fertilization (IVF). Objective: To assess whether the association between birth defects and cancer is greater in children conceived via IVF compared with children conceived naturally. Design, Setting, and Participants: This cohort study of live births, birth defects, and cancer from Massachusetts, New York, North Carolina, and Texas included 1 000 639 children born to fertile women and 52 776 children conceived via IVF (using autologous oocytes and fresh embryos) during 2004-2016 in Massachusetts and North Carolina, 2004-2015 in New York, and 2004-2013 in Texas. Children were followed up for an average of 5.7 years (6 008 985 total person-years of exposure). Data analysis was conducted from April 1 to August 31, 2020. Exposures: Conception by IVF for state residents who gave birth to liveborn singletons during the study period. Birth defect diagnoses recorded by statewide registries. Main Outcomes and Measures: Cancer diagnosis as recorded by state cancer registries. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% CIs for birth defect-cancer associations separately in fertile and IVF groups. Results: A total of 1 000 639 children (51.3% boys; 69.7% White; and 38.3% born between 2009-2012) were in the fertile group and 52 776 were in the IVF group (51.3% boys; 81.3% White; and 39.6% born between 2009-2012). Compared with children without birth defects, cancer risks were higher among children with a major birth defect in the fertile group (hazard ratio [HR], 3.15; 95% CI, 2.40-4.14) and IVF group (HR, 6.90; 95% CI, 3.73-12.74). The HR of cancer among children with a major nonchromosomal defect was 2.07 (95% CI, 1.47-2.91) among children in the fertile group and 4.04 (95% CI, 1.86-8.77) among children in the IVF group. The HR of cancer among children with a chromosomal defect was 15.45 (95% CI, 10.00-23.86) in the fertile group and 38.91 (95% CI, 15.56-97.33) in the IVF group. Conclusions and Relevance: This study found that among children with birth defects, those conceived via IVF were at greater risk of developing cancer compared with children conceived naturally.

Limits of current male fertility testing.

In the current approach to male fertility testing, basic semen analysis has limitations as a predictor of fertility status, and the technology is fraught with variability. Nonetheless, it remains the cornerstone of the evaluation of the male infertility, and we recommend adherence to most recent World Health Organization guidelines. Although the current sperm function tests (bioassays) have important drawbacks, they are still valuable as research tools. Sperm quality assays with analysis of sperm DNA fragmentation need further investigation before they can be recommended for routine clinical use. The answer to the many current challenging questions relies on identifying spermatogenesis pathologies and the resulting sperm dysfunctions at the cellular and molecular levels. New discoveries may bring answers or new avenues to explore.

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 αvß3, 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 αvß3, 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 αvß3 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.

MFGE8 regulates TGF-ß-induced epithelial mesenchymal transition in endometrial epithelial cells in vitro.

This study investigated the role of milk fat globule-epidermal growth factor-factor 8 (MFGE8) in TGF-ß-induced epithelial-mesenchymal transition (EMT) of endometrial epithelial cells. These were in vitro studies using human endometrial epithelial cells and mouse blastocysts. We investigated the ability of TGF-ß to induce EMT in endometrial epithelial cells (HEC-1A) by assessment of cytological phenotype (by light and atomic force microscopy), changes in expression of the markers of cell adhesion/differentiation E- and N-cadherin, and of the transcription factor Snail (by immunofluorescence and immunoblotting), and competence to support embryo attachment in a mouse blastocyst outgrowth assay. We also studied the effects of E-cadherin expression in cells transfected by retroviral shRNA vectors specifically silencing MFGE8. Results demonstrated that TGF-ß induced EMT as demonstrated by phenotypic cell changes, by a switch of cadherin expression as well as by upregulation of the expression of the mesenchymal markers Snail and Vimentin. Upon MFGE8 knockdown, these processes were interfered with, suggesting that MFGE8 and TGF-ß together may participate in regulation of EMT. This study demonstrated for the first time that endometrial MFGE8 modulates TGF-ß-induced EMT in human endometrium cells.

Predictive factors for ovarian response in a corifollitropin alfa/GnRH antagonist protocol for controlled ovarian stimulation in IVF/ICSI cycles.

BACKGROUND: This secondary analysis aimed to identify predictors of low (<6 oocytes retrieved) and high ovarian response (>18 oocytes retrieved) in IVF patients undergoing controlled ovarian stimulation with corifollitropin alfa in a gonadotropin-releasing hormone (GnRH) antagonist protocol. METHODS: Statistical model building for high and low ovarian response was based on the 150 µg corifollitropin alfa treatment group of the Pursue trial in infertile women aged 35-42 years (n = 694). RESULTS: Multivariable logistic regression models were constructed in a stepwise fashion (P <0.05 for entry). 14.1 % of subjects were high ovarian responders and 23.2 % were low ovarian responders. The regression model for high ovarian response included four independent predictors: higher anti-Müllerian hormone (AMH) and antral follicle count (AFC) increased the risk, and higher follicle-stimulating hormone (FSH) levels and advancing age decreased the risk of high ovarian response. The regression model for low ovarian response also included four independent predictors: advancing age increased the risk, and higher AMH, higher AFC and longer menstrual cycle length decreased the risk of low ovarian response. CONCLUSIONS: AMH, AFC and age predicted both high and low ovarian responses, FSH predicted high ovarian response, and menstrual cycle length predicted low ovarian response in a corifollitropin alfa/GnRH antagonist protocol. TRIAL REGISTRATION NUMBER: NCT01144416 , Protocol P06029.

Effects of adipocyte-secreted factors on decidualized endometrial cells: modulation of endometrial receptivity in vitro.

Obesity is defined as an excessive accumulation of adipose tissue that may lead to health complications. Mounting evidence indicates that obesity has a negative impact on fertility. Yet, the link between adipose tissue biology and infertility remains unclear. We aimed to investigate the communication between the adipose tissue and the reproductive system and the importance of this cross talk for the development of a receptive endometrium. To that end, we generated an in vitro model with endometrial and adipocyte cell lines. Sexual hormones, progesterone and estradiol, were used to decidualize endometrial cells and sensitize adipocytes. Decidualization produced a simultaneous increase of adipokine receptors in endometrial cells paralleling changes in their receptivity status. Furthermore, sensitization of 3T3-L1 adipocytes increased mRNA levels of leptin and resistin and decreased the expression of adiponectin and chemerin levels. This was accompanied by increased isoproterenol-induced lipolysis and reduced insulin-stimulated glucose uptake. Lastly, conditioned culture medium of those sensitized adipocytes was used to feed endometrial cells. This treatment resulted in (i) upregulation of genes previously identified as positive regulators of endometrial receptivity, such as leukemia inhibitory factor and glutathione peroxidase 3, and (ii) downregulation of interleukin-15 and mucin1, both genes negatively related with endometrial receptivity. Our results indicate that the endocrine communication between adipose tissue and the reproductive system is bidirectional and stress the importance of the adipose tissue to modulate the reproductive fitness.

Impact of serum estradiol levels on the implantation rate of cleavage stage cryopreserved-thawed embryos transferred in programmed cycles with exogenous hormonal replacement.

PURPOSE: To investigate the impact of late follicular phase serum estradiol (E2) levels on implantation and pregnancy outcomes of cleavage stage cryopreserved/thawed embryos transferred in programmed cycles with exogenous hormonal replacement. METHODS: Retrospective cohort analysis of IVF patients with transfer of cryopreserved-thawed day-3 embryos in E2 and progesterone (P4) supplemented cycles (n = 208 cycles). MAIN OUTCOME MEASURES: implantation and pregnancy rates according to late follicular phase serum E2 levels and early secretory phase E2/P4 ratios. RESULTS: Logistic regression performed for embryo implantation and for pregnancy outcome in relation to E2 (day 15), P4 (day 15 and 16), before (crude analysis) and after adjustment (adjusted analysis) for baseline characteristics (including age, BMI, serum basal cycle day 3 FSH levels, embryo quality, endometrial lining thickness) showed no significant association. Similarly, ROC analysis showed no impact of cycle day 16 E2/P4 ratio. CONCLUSIONS: Neither late follicular phase serum E2 nor the early E2/P4 ratio were able to predict implantation or pregnancy outcome of day-3 cryopreserved-thawed embryos transferred in artificially programmed cycles.

Endometriosis may be associated with mitochondrial dysfunction in cumulus cells from subjects undergoing in vitro fertilization-intracytoplasmic sperm injection, as reflected by decreased adenosine triphosphate production.

OBJECTIVE: To determine whether endometriosis is associated with mitochondrial dysfunction in cumulus (granulosa [GC]) cells of subjects undergoing IVF-intracytoplasmic sperm injection (ICSI). DESIGN: Prospective cohort study. SETTING: An IVF clinic in a tertiary academic care center. PATIENT(S): Eleven women with endometriosis and 39 controls. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Cumulus cell adenosine triphosphate (ATP) levels, mitochondrial DNA (mtDNA), and genomic DNA (gDNA) number. RESULT(S): Cumulus cell ATP content was 65% lower in subjects with surgically proven endometriosis (median 312.5 attomoles/ng total DNA, interquartile range = 116.0-667.8) compared with controls (median 892.4 attomoles/ng total DNA, interquartile range = 403.0-1,412.2). There was no significant difference in mtDNA:gDNA ratio. There were no significant differences in age, body mass index (BMI), basal serum FSH level, total oocyte number, metaphase II (M2) oocyte number, metaphase I oocyte number, percentage of M2 oocytes, fertilization rate, implantation rate, or pregnancy rate (PR). Multivariate regression analysis showed significant positive correlations between ATP and [1] M2 oocyte number (r = 0.307) and [2] pregnancy (r = 0.332). There were also trends toward positive correlations between ATP and [3] age (r = 0.283), [4] total number of oocytes (r = 0.271), [5] percentage of M2 oocytes (r = 0.249), and [6] implantation rate (r = 0.293). There were no statistically significant correlations between mtDNA:gDNA ratio and any demographic factors or clinical outcomes measured. CONCLUSION(S): Surgically confirmed endometriosis may be associated with cumulus cell mitochondrial dysfunction in subjects undergoing IVF-ICSI for infertility, as reflected by decreased ATP production.

Sperm functional tests.

Several semen parameters are used to discriminate the fertile male from the subfertile male. The most widely used parameters are sperm concentration, motility, progressive motility, and sperm morphology. Semen analysis is usually applied as described in the World Health Organization manual for semen analysis. In addition to a routine semen analysis, sperm functional tests have been described for many years, which in most cases are regarded as research tools and not part of the routine semen testing in an infertility clinic. In this review we report on the value of four sperm function tests: the sperm penetration assay, the sperm-zona pellucida binding tests, the acrosome reaction, and the hyaluronan binding assay. For each test we describe the current value, the indication for performing the test, how to interpret the results, and its therapeutic implications. Our data show that sperm functional assays are highly predictive of IVF outcome results and have the potential to assist in clinical decision making, especially to avoid the current long-standing treatment with IUI and to direct the patients to intracytoplasmic sperm injection without delay when sperm functional testing fails. We believe that advances in molecular biology techniques will allow us to develop simpler sperm function assays in the near future. This will undoubtedly help clinicians in optimizing male factor infertility diagnosis and treatment.

Antimüllerian hormone regulates stem cell factor expression in human granulosa cells.

OBJECTIVE: To determine whether there is a correlation between antimüllerian hormone (AMH) and stem cell factor (SCF) in serum, follicular fluid (FF), and granulosa cells (GCs), and to investigate a possible regulatory mechanism of AMH on SCF in human granulosa cells. DESIGN: Prospective clinical and experimental study. SETTING: Academic center. PATIENT(S): 163 women undergoing IVF. INTERVENTION(S): Serum, FF, and GCs obtained in all women, primary cultures of human GCs. MAIN OUTCOME MEASURE(S): AMH and SCF were analyzed in serum, FF, and GCs, using enzyme-linked immunosorbent assay, reverse-transcription polymerase chain reaction, and immunoblotting. RESULT(S): There was a significant negative correlation between AMH and SCF protein level in FF, and in the mRNA expression of AMH and SCF in GCs. Conversely, there was no correlation between AMH and SCF levels in serum. In primary cultures of human GCs, SCF was down-regulated by treatment with recombinant human AMH and was increased by cyclic adenosine 3':5' monophosphate (cAMP) in a dose-dependent manner. A protein kinase A (PKA) inhibitor (H89) significantly reversed the effects of recombinant human AMH and cAMP on SCF mRNA and protein expression. CONCLUSION(S): This is the first report on a modulatory role for AMH as an ovarian/follicular autocrine/paracrine factor controlling SCF expression via the cAMP/PKA pathway.

Characterization of secreted proteins of 2-cell mouse embryos cultured in vitro to the blastocyst stage with and without protein supplementation.

PURPOSE: To identify the secreted proteins of murine embryos grown in vitro. METHODS: Two-cell mouse embryos (n=432) were randomly allocated to culture to the blastocyst stage in protein-free and in protein-supplemented (3 % BSA) media. Proteins were separated by SDS-PAGE; bands were visualized by coomassie staining, followed by in-gel trypsin digestion and liquid chromatography-tandem mass spectrometry. RT-PCR and confocal microscopy were used to confirm gene/protein expression in blastocysts. RESULTS: Of all individually identified proteins, 34 and 23 were found in embryos cultured without and with BSA, respectively, and 20 were common. Identified proteins having an N-terminal secretory sequence or transmembrane domains located on the extracellular backbone were postulated as secreted proteins. Gene and protein expression for two selected molecules were confirmed. Functional analysis revealed over-represented processes related to lipid metabolism, cyclase activity, and cell adhesion/membrane functions. CONCLUSIONS: This study provided evidence to further characterize secreted proteins by mouse embryos grown from the 2-cell to the blastocyst stage in vitro. Because of homology between murine and human, these results may provide information to be translated to the clinical setting.

Role for the endometrial epithelial protein MFG-E8 and its receptor integrin αvß3 in human implantation: results of an in vitro trophoblast attachment study using established human cell lines.

OBJECTIVE: To investigate the role of MFG-E8 and its receptor integrin αvß3 in the attachment of trophoblast cells to the endometrial epithelium. DESIGN: Experimental in vitro study. SETTING: Academic center. PATIENT(S): None. INTERVENTION(S): By using a well-differentiated endometrial adenocarcinoma cell line (Ishikawa cells) and choriocarcinoma human trophoblast cells (Jar cells), an in vitro assay mimicking human implantation was established. To investigate the impact of blocking MFG-E8 and integrin αvß3, we pretreated the cell lines with antibodies against those proteins at different concentrations before the attachment assay. MAIN OUTCOME MEASURE(S): Attachment rate of Jar spheroids to the epithelial cell monolayer. RESULT(S): Pretreatment of Ishikawa cells with anti-MFG-E8 antibody caused a dose-dependent and significant inhibition of attachment. On the other hand, pretreatment of Jar spheroids did not result in a significant effect on the attachment rate. Pretreatment of Ishikawa cells as well as Jar spheroids with anti-integrin αvß3 antibodies resulted in a dose-dependent, significant inhibition of attachment. CONCLUSION(S): This study showed that blocking MFG-E8 and its receptor integrin αvß3 in Ishikawa cells diminishes Jar spheroid attachment. Moreover, blocking integrin αvß3 in the trophoblastic cells also diminished their attachment to the Ishikawa monolayer.

Tumor necrosis factor α up-regulates endometrial milk fat globule-epidermal growth factor 8 protein production via nuclear factor κB activation, resulting in cell migration of epithelial cells.

OBJECTIVE: To explore the role of tumor necrosis factor (TNF) α, an early embryonic product, on endometrial epithelial cell migration and endometrial milk fat globule-epidermal growth factor 8 protein (MFG-E8) production. DESIGN: In vitro study. SETTING: Academic center. INTERVENTION(S): Ishikawa cells, used as surrogates for human epithelial cells, were treated with and without TNF-α. MAIN OUTCOME MEASURE(S): Effect of TNF-α on intracellular MFG-E8 protein was evaluated with the use of ELISA, Western blot, and subcellular fractionation. Specific inhibitors were used to study TNF-α mechanism of action. Effect of TNF-α on cell migration was studied with the use of a wound healing assay and reorganization of E-cadherin. RESULT(S): TNF-α induced: 1) significant up-regulation of MFG-E8 intracellular protein, which was attenuated by pretreatment with a specific inhibitor of nuclear factor κB; 2) increased transcription of MFG-E8 and other proinflammatory factors, such as interleukins 6 and 8, which were suppressed by cotreatment with hCG; and 3) significant cell migration with E-cadherin remodeling, changes associated with subcellular MFG-E8 relocalization. CONCLUSION(S): TNF-α up-regulates endometrial epithelial cell migration and MFG-E8 production, which are critical steps required for the endometrial changes during menstrual cycle as well as during embryonic attachment and invasion.