An Estrogen-NK Cells Regulatory Axis in Endometriosis, Related Infertility, and Miscarriage.

Endometriosis is a common estrogen-dependent condition that impacts 8-10% of women in their reproductive age, resulting in notable pain, morbidity, and infertility. Despite extensive research endeavors, the precise cause of endometriosis remains elusive, and the mechanisms contributing to its associated infertility are still not well comprehended. Natural killer (NK) cells, vital innate immune cells crucial for successful pregnancy, have been investigated for their potential involvement in the pathogenesis of endometriosis. Prior research has mainly concentrated on the diminished cytotoxicity of NK cells in endometrial fragments that evade the uterus. Interestingly, accumulating evidence suggests that NK cells play multifaceted roles in regulating the biology of endometrial stromal cells (ESCs), promoting local immune tolerance, influencing endometrial receptivity, oocyte development, and embryo implantation, thereby contributing to infertility and miscarriage in patients with endometriosis. In this comprehensive review, our goal is to summarize the current literature and provide an overview of the implications of NK cells in endometriosis, especially concerning infertility and pregnancy loss, under the influence of estrogen.

Transcriptomic Analysis Reveals Intrinsic Abnormalities in Endometrial Polyps.

Endometrial polyps (EPs) are benign overgrowths of the endometrial tissue lining the uterus, often causing abnormal bleeding or infertility. This study analyzed gene expression differences between EPs and adjacent endometrial tissue to elucidate intrinsic abnormalities promoting pathological overgrowth. RNA sequencing of 12 pairs of EPs and the surrounding endometrial tissue from infertile women revealed 322 differentially expressed genes. Protein-protein interaction network analysis revealed significant alterations in specific signaling pathways, notably Wnt signaling and vascular smooth muscle regulation, suggesting these pathways play critical roles in the pathophysiology of EPs. Wnt-related genes DKK1 and DKKL1 were upregulated, while GPC3, GREM1, RSPO3, SFRP5, and WNT10B were downregulated. Relevant genes for vascular smooth muscle contraction were nearly all downregulated in EPs, including ACTA2, ACTG2, KCNMB1, KCNMB2, MYL9, PPP1R12B, and TAGLN. Overall, the results indicate fundamental gene expression changes promote EP formation through unrestrained growth signaling and vascular defects. The intrinsic signaling abnormalities likely contribute to clinical symptoms of abnormal uterine bleeding and infertility common in EP patients. This analysis provides molecular insights into abnormal endometrial overgrowth to guide improved diagnostic and therapeutic approaches for this troublesome women's health condition. Confirmation of expanded cohorts and further investigations into implicated regulatory relationships are warranted.

Hysterosalpingography: a step up for dose reduction.

AIM: To evaluate the efficiency of last image capture in interpreting a hysterosalpingogram (HSG) when compared to conventional spot views; to confirm its validity in showing pathology; to establish its use as the preferred method; and to decrease the radiation dose to the patient. MATERIALS AND METHODS: The study population consisted of women aged ≥18 years. A standard technique was performed including additional five last image capture after each spot view. Every patient had two stacks of images, one with the exposure film and one with the last image capture. The images were interpreted separately (high-dose versus low-dose) and blindly by two radiologists with different levels of training assessing for uterine abnormalities, fallopian tube abnormalities, peritoneal spillage, and incidental findings. Inter-reading variability was calculated using Kohen's kappa. RESULTS: Discrepancies between exposure film and last image capture were detected in only a minority of cases for all variables. Except for the presence of strictures, there was at least substantial agreement between the readers and almost perfect agreement regarding peritoneal spillage and fallopian tube patency, both on exposure film and last image capture. CONCLUSION: Reduction in radiation dose without compromising the diagnostic efficacy of HSG is mandatory. If the study is of sufficient quality and deemed negative on last image capture, conventional spot view can be avoided. If further detail is required, standard spot views can still be obtained. Using last image capture instead of spot films has the potential to reduce the overall radiation dose by up to 78%.

Analysis of the microbiota composition in the genital tract of infertile patients with chronic endometritis or endometrial polyps.

Background: The previous researches show that infertile patients have a higher incidence of endometritis and endometrial polyps, and the occurrence of these two diseases is related to changes in the microbiota of the genital tract. We aim to determine the composition and changing characteristics of the microbiota in the genital tract (especially the endometrium) of infertile patients with chronic endometritis or endometrial polyps, and find the correlation between it and the occurrence of diseases. Methods: This is a prospective study. We collected genital tract biopsy samples from 134 asymptomatic infertile patients receiving assisted reproductive therapy before embryo transfer. Through pathological examination and 16S ribosomal RNA(16S rRNA) sequencing, we determined the distribution of chronic endometritis and endometrial polyps in these patients, as well as their distribution of reproductive tract microorganisms. Results: Compared with the normal control group, the microbial group of reproductive tract in patients with chronic endometritis and endometrial polyps is changed, and there are significant species differences and relative abundance differences in the vagina, cervix and uterine cavity. Lactobacillus, the dominant flora of female genital tract, showed a change in abundance in patients with endometrial diseases. Endometrial microbiota composed of Staphylococcus, Gardnerella, Atopobium, Streptococcus, Peptostreptococcus, Chlamydia, Fusobacterium, Acinetobacter, etc. are related to chronic endometritis and endometrial polyps. Conclusion: The results showed that, compared with the normal control group, the endometrial microbiota of infertile patients with chronic endometritis or endometrial polyps did have significant changes in the relative abundance distribution of species, suggesting that changes in local microecology may be an important factor in the occurrence of disease, or even adverse pregnancy outcomes. The further study of endometrial microecology may provide a new opportunity to further improve the diagnosis and treatment strategy of chronic endometritis.

Novel mutations in TRIP13 lead to female infertility with oocyte maturation arrest.

Oocyte maturation arrest (OMA) refers to a rare clinical phenomenon of oocyte maturation disorder caused by abnormal meiosis, which is also one of the primary causes of female infertility. The clinical manifestations of these patients are often characterized with failure to obtain mature oocytes after repeated ovulation stimulation and/or induced in vitro maturation. To date, mutations in PATL2, TUBB8 and TRIP13 have been demonstrated to be associated with OMA, but studies on the genetic-based factors and mechanisms of OMA are still incomplete. In this study, peripheral blood from 35 primary infertile women characterized with recurrent OMA during assisted reproductive technology (ART) were subjected to whole-exome sequencing (WES). By using Sanger sequencing and co-segregated analysis, we identified four pathogenic variants in TRIP13. Proband 1 had a homozygous missense mutation of c.859A>G appeared on the 9th exon, which resulted in substitution of Ile287 to valine (p.Ile287Val); proband 2 had a homozygous missense mutation of c.77A>G on the 1st exon, which resulted in substitution of His26 to arginine (p.His26Arg); and proband 3 had compound heterozygous mutations of c.409G>A and c.1150A>G on the 4th and 12th exon, which resulted in the substitutions of Asp137 to asparagine (p.Asp137Asn) and Ser384 to glycine (p.Ser384Gly) in the encoded protein respectively. Three of these mutations have not been reported previously. Further, transfection of plasmids harboring the respective mutated TRIP13 in HeLa cells resulted in changes in TRIP13 expression and abnormal cell proliferation as demonstrated by western blotting and cell proliferation assay respectively. This study further summarizes the TRIP13 mutations reported previously and expands the mutation spectrum of TRIP13 pathogenic variants, thereby providing a valuable reference for further research on the pathogenic mechanism of OMA associated with TRIP13 mutations.

Association between endometrial senescent cells and immune cells in women with repeated implantation failure.

PURPOSE: The aim of this study was to compare women with recurrent implantation failure (RIF) and control group in terms of the associations between p16-positive senescent cells and certain types of immune cells in human endometrium during the mid-luteal phase METHODS: Immunohistochemical staining was performed in 116 endometrial biopsies taken from 57 women presenting RIF, and control group of 59 women who became pregnant after the first intracytoplasmic sperm injection. Endometrial tissue sections were stained immunohistochemically for p16 (Senescent cells), CD4 (T-helpers), CD8 (T-killers), CD14 (Monocytes), CD68 (Macrophages), CD56 (Natural killers), and CD79α (B-cells). The percentage of positively stained cells for each marker was calculated by HALO image analysis software. The quantity and the relationship between senescent cells and immune cells were assessed and compared between the two groups. RESULTS: The correlation coefficient was highest between senescent cells and CD4+ cells and was lowest between senescent cells and CD14+ cells in RIF women, similarly to the control group. However, most of the observed correlations among senescent and immune cells weaken notably or disappear in the RIF group. When comparing senescent cell-to-immune cell quantitative ratios, only p16+/CD4+ cell ratio was significantly higher in RIF women as compared with patients from the control group. CONCLUSION: Our study indicates that the quantity of senescent cells in human endometrium during the mid-luteal phase has the strongest association with the amount of T helpers. Moreover, the specificity of this association might have an important impact on the occurrence of RIF.

A novel homozygous variant in ZFP36L2 cause female infertility due to oocyte maturation defect.

Normal oocyte maturation is an important requirement for the success of human reproduction, and defects in this process will lead to female infertility and repeated IVF/ICSI failures. In order to identify genetic factors that are responsible for oocyte maturation defect, we used whole exome sequencing in the affected individual with oocyte maturation defect from a consanguineous family and identified a homozygous variant c.853_861del (p.285_287del) in ZFP36L2. ZFP36L2 is a RNA-binding protein, which regulates maternal mRNA decay and oocyte maturation. In vitro studies showed that the variant caused decreased protein levels of ZFP36L2 in oocytes due to mRNA instability and might lead to the loss of its function to degrade maternal mRNAs. Previous study showed that the pathogenic variants in ZFP36L2 were associated with early embryonic arrest. In contrast, we identified a novel ZFP36L2 variant in the affected individual with oocyte maturation defect, which further broadened the mutational and phenotypic spectrum of ZFP36L2, suggesting that ZFP36L2 might be a genetic diagnostic marker for the affected individuals with oocyte maturation defect.

Bi-allelic pathogenic variants in PABPC1L cause oocyte maturation arrest and female infertility.

Oocyte maturation arrest is one of the important causes of female infertility, but the genetic factors remain largely unknown. PABPC1L, a predominant poly(A)-binding protein in Xenopus, mouse, and human oocytes and early embryos prior to zygotic genome activation, plays a key role in translational activation of maternal mRNAs. Here, we identified compound heterozygous and homozygous variants in PABPC1L that are responsible for female infertility mainly characterized by oocyte maturation arrest in five individuals. In vitro studies demonstrated that these variants resulted in truncated proteins, reduced protein abundance, altered cytoplasmic localization, and reduced mRNA translational activation by affecting the binding of PABPC1L to mRNA. In vivo, three strains of Pabpc1l knock-in (KI) female mice were infertile. RNA-sequencing analysis showed abnormal activation of the Mos-MAPK pathway in the zygotes of KI mice. Finally, we activated this pathway in mouse zygotes by injecting human MOS mRNA, and this mimicked the phenotype of KI mice. Our findings reveal the important roles of PABPC1L in human oocyte maturation and add a genetic potential candidate gene to be screened for causes of infertility.

Metabonomic analysis of follicular fluid in patients with diminished ovarian reserve.

Background: Ovarian reserve is an important factor determining female reproductive potential. The number and quality of oocytes in patients with diminished ovarian reserve (DOR) are reduced, and even if in vitro fertilization-embryo transfer (IVF-ET) is used to assist their pregnancy, the clinical pregnancy rate and live birth rate are still low. Infertility caused by reduced ovarian reserve is still one of the most difficult clinical problems in the field of reproduction. Follicular fluid is the microenvironment for oocyte survival, and the metabolic characteristics of follicular fluid can be obtained by metabolomics technology. By analyzing the metabolic status of follicular fluid, we hope to find the metabolic factors that affect the quality of oocytes and find new diagnostic markers to provide clues for early detection and intervention of patients with DOR. Methods: In this research, 26 infertile women with DOR and 28 volunteers with normal ovarian reserve receiving IVF/ET were recruited, and their follicular fluid samples were collected for a nontargeted metabonomic study. The orthogonal partial least squares discriminant analysis model was used to understand the separation trend of the two groups, KEGG was used to analyze the possible metabolic pathways involved in differential metabolites, and the random forest algorithm was used to establish the diagnostic model. Results: 12 upregulated and 32 downregulated differential metabolites were detected by metabolic analysis, mainly including amino acids, indoles, nucleosides, organic acids, steroids, phospholipids, fatty acyls, and organic oxygen compounds. Through KEGG analysis, these metabolites were mainly involved in aminoacyl-tRNA biosynthesis, tryptophan metabolism, pantothenate and CoA biosynthesis, and purine metabolism. The AUC value of the diagnostic model based on the top 10 metabolites was 0.9936. Conclusion: The follicular fluid of patients with DOR shows unique metabolic characteristics. These data can provide us with rich biochemical information and a research basis for exploring the pathogenesis of DOR and predicting ovarian reserve function.

Subtle changes in perivascular endometrial mesenchymal stem cells after local endometrial injury in recurrent implantation failure.

Improvements in reproductive techniques have resulted in the live birth rates from IVF procedures increasing from 5% to approximately 30% in recent decades but has plateaued since. Emerging preclinical and clinical data implicates endometrial receptivity deficiencies in patients with recurrent implantation failure (RIF) as the predominant factor hindering successful implantation. Mechanisms on how local endometrial injury (LEI) improves implantation rates in patients with RIF are currently unknown. We hypothesized that LEI may influence perivascular endometrial mesenchymal stem/progenitor cells (eMSCs) which are thought to regenerate the stromal vascular component of the functional layer every month. Here, we assessed the effect of LEI on the proportion and function of eMSCs present in consecutive LEI biopsies. Consecutive paired mid-luteal phase endometrial biopsies obtained from patients with RIF were digested to single cells and the proportion of SUSD2-expressing cells determined. Growth kinetics and decidualization were compared between the consecutive LEI samples. A mid-luteal LEI altered the decidualization capacity of SUSD2+ eMSCs in women with RIF, but not their proportion or clonogenicity. With the potential of LEI to improve IVF outcomes in women with RIF, additional investigations are needed to understand the impact of the altered decidualization response in eMSCs.

Hysteroscopic injections of autologous endometrial cells and platelet-rich plasma in patients with thin endometrium: a pilot randomized study.

The aim of this study was to evaluate the efficacy of hysteroscopically controlled injections of autologous platelet-rich plasma (PRP) and autologous endometrial cells as a treatment for infertile women with thin endometrium. The study enrolled 115 patients with thin endometrium (< 7 mm at implantation window) and infertility, who were divided into groups: Group 1 (the control) underwent conservative therapy; Group 2 received intraendometrial PRP injections instead of the conservative therapy; Group 3 received identical injections after conservative therapy; Group 4 received injections of the autologous endometrial cells suspended in PRP. A single injection dose of PRP contained 0.6-0.7 × 1011 of platelets. The levels of PDGF-BB and VEGF in PRP were increased compared with ordinary plasma. The autologous endometrial cells, obtained from pipelle biopsies, constituted heterogeneous cell populations containing stromal and epithelial cells. Intraendometrial PRP injections had significant impact on endometrial thickness and local microcirculation in Group 2 and Group 3. In Group 4, injections of PRP reinforced with endometrial cells also facilitated a significant increase in endometrial thickness. This work describes a novel approach for infertility treatment in patients with refractory thin endometrium. PRP injections and injections of the endometrial cells suspended in PRP into endometrium enhanced cell proliferation and angiogenesis.

When a balloon catheter or tenaculum is required for cervical traction during hysterosalpingography.

The aim of this study was to define the actual rate of the traction needed and the balloon catheter or tenaculum requirement for hysterosalpingography (HSG) examinations, and to investigate the correlation between pain scores with the type of traction, operator, parity or the type of infertility. 788 patients undergoing HSG participated in the trial. The HSG examinations were completed in 58% of the patients (458) without any traction. Traction was needed in 42% of patients, those with the balloon catheter in 26.9%, and those with the tenaculum only at 15%. Patients with balloon catheter traction had similar pain scores to those using tenaculum traction. The pain scores changed according to the operator. HSG examinations should be performed step-by-step and the need for traction evaluated during the procedure.IMPACT STATEMENTWhat is already known on this subject? HSG is a technique to evaluate fallopian tube patency and other potential intrauterine pathology in infertile women.What do the results of this study add? Traction was not needed in more than half of the HSG examinations. The pain due to the balloon catheter and tenaculum is similar.What the implications are of these findings for clinical practice and/or further research? HSG examinations should be performed step-by-step by checking the need for traction. Traction with the balloon catheter prevents the uterine spasm, infection and bleeding complications during or after the HSG.

Endometriosis-associated infertility diagnosis based on saliva microRNA signatures.

RESEARCH QUESTION: Can a saliva-based miRNA signature for endometriosis-associated infertility be designed and validated by analysing the human miRNome? DESIGN: The prospective ENDOmiARN study (NCT04728152) included 200 saliva samples obtained between January 2021 and June 2021 from women with pelvic pain suggestive of endometriosis. All patients underwent either laparoscopy, magnetic resonance imaging, or both. Patients diagnosed with endometriosis were allocated to one of two groups according to their fertility status. Data analysis consisted of identifying a set of miRNA biomarkers using next-generation sequencing, and development of a saliva-based miRNA signature of infertility among patients with endometriosis based on a random forest model. RESULTS: Among the 153 patients diagnosed with endometriosis, 24% (n = 36) were infertile and 76% (n = 117) were fertile. Small RNA-sequencing of the 153 saliva samples yielded approximately 3712 M raw sequencing reads (from ∼13.7 M to ∼39.3 M reads/sample). Of the 2561 known miRNAs, the feature selection method generated a signature of 34 miRNAs linked to endometriosis-associated infertility. After validation, the most accurate signature model had a sensitivity, specificity and area under the curve of 100%. CONCLUSION: A saliva-based miRNA signature for endometriosis-associated infertility is reported. Although the results still require external validation before using the signature in routine practice, this non-invasive tool is likely to have a major effect on care provided to women with endometriosis.

A novel homozygous C-terminal deletion in BTG4 causes zygotic cleavage failure and female infertility.

PURPOSE: We aimed to identify pathogenic variants in a female patient with primary infertility and recurrent failure of in vitro fertilization with zygotic cleavage failure. METHODS: The genomic DNA from the affected individual was subjected to whole-exome sequencing and the variant was confirmed by Sanger sequencing. The functional effect of the identified variant was further investigated in 293 T cells. RESULTS: We identified a novel homozygous deletion in BTG4 (c.580_616del) in the affected individual. The deletion results in frameshift and replacement of the last 29 residues (aa195-223) with 66 random amino acids. The mutated amino acid residues are highly conserved among mammalian species. Co-immunoprecipitation in 293 T cells showed that the mutation abolished the interaction between BTG4 and PABPN1L. CONCLUSION: This study conforms previous studies and expands the mutational spectrum of BTG4. Our findings prove the functional importance of the C-terminal of BTG4. BTG4 is a potential diagnostic and therapeutic target for patients suffering from zygotic cleavage failure.

Effect of different antibiotic therapies on the reproductive outcomes of fresh embryo transfer for chronic endometritis: A retrospective cohort study.

OBJECTIVE: To investigate the reproductive outcomes by comparing two kinds of antibiotic schemes for chronic endometritis (CE) in infertile women's fresh embryo transfer (FET) cycles and identify subgroups of patients with CE who need long-term antibiotics treatment. DESIGN: A retrospective cohort study. SETTING: University-based reproductive medical center. PATIENT(S): A total of 492 women with CD138-positive plasmacytes per 10 high-power fields (CD138+/10HPF). INTERVENTION(S): Hysteroscopy was performed and endometrial biopsy samples were collected in the proliferative phase. Long-term or short-term antibiotics were administrated. After antibiotics treatment, patients underwent in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) and received ET. MAIN OUTCOME MEASURE(S): Ongoing pregnancy rate, clinical pregnancy rate, clinical miscarriage rate. RESULT (S): There were no significant differences in pregnancy outcomes between patients with CD138+/10HPF 1-4 (low-grade CE) who received long-term antibiotic therapy and short-term antibiotics groups. Among women with CD138+/10HPF ≥5 (high-grade CE), live birth rate (48.4% vs. 14.7%, p = .001), clinical pregnancy rate (66.7% vs. 35.3%, p = .002) and ongoing pregnancy rate (59.1% vs. 20.6%, p < .001) in the long-term arm were significantly higher than that in the short-term arm. The clinical miscarriage rate (21.0% vs. 58.3%, p = .013) was statistically lower in the long-term antibiotics group, but no statistical differences were found between the two groups in preterm delivery rate. CONCLUSION: Long-term antibiotics treatment was a sensible choice to improve pregnancy outcomes in women with CD138+/10HPF ≥5 (high-grade CE). The pregnancy outcomes of women with low-grade CE only defined by histological diagnosis were not greatly improved after antibiotic therapy. Therefore, we recommended the proper diagnosis criteria were CD138+/10HPF ≥5 pathologically.

Dysfunctional regulation of pivotal and key inflammatory pathways in infertile Indian women with genital tuberculosis.

PROBLEM: Diagnosis of female genital tuberculosis (FGTB) remains elusive due to the paucibacillary nature of the disease. We evaluated if analysis of inflammatory pathways of endometrial tissue could establish a better diagnosis of FGTB. METHOD OF STUDY: One hundred and four infertile women suspected of having GTB or having been treated for GTB in the past, underwent endometrial biopsies for diagnosis and Gene Inflammatory Pathways analysis at our center between 2018-2020. Diagnosis of FGTB was based on acid-fast bacilli culture, immunocytochemistry, nested-polymerase chain reaction, histopathological examination, TB GeneXpert, or combinations thereof. Gene expression profiles were also analyzed. RESULTS: Based on diagnostic tests of 104 women, 44 (42%) were considered TB-positive, 35 (34%) TB-negative, and 25 (24%) TB-negative after TB treatment in the past. Inflammatory pathways were significantly upregulated in TB-positive women versus TB-negative (41% vs. 6%; p = .0005), and in women who were TB-negative after TB treatment in the past versus TB-negative (never treated for TB in the past) (38% vs. 6%; p = .0037). Two-hundred seventy-one genes were upregulated, and 61 genes were downregulated in TB-positive women versus those who were TB-negative. Differentially expressed genes were mapped to various interlinked inflammatory signaling pathways, including mitogen-activated protein kinase (MAPK), Natural Killer (NK) cells, nuclear factor kappa-B (NF-kB), tumor necrosis factor (TNF), and Toll-like receptors (TLR) signaling. CONCLUSIONS: Inflammatory pathways and gene expression profiles add to the diagnostic tools to identify TB-positive women at an early stage. The results from this study are still experimental and large multi-centric studies are suggested before their recommendation in routine clinical practice.

Diagnosis of Genital Tuberculosis in Infertile Women by Using the Composite Reference Standard.

Female genital tuberculosis (FGTB) can be asymptomatic or even masquerade as other gynecological conditions. Conventional methods of FGTB diagnosis include various imaging, bacteriological, molecular, and pathological techniques that are only positive in a small percentage of patients, leaving many cases with undiagnosed condition. In the absence of a perfect diagnostic method, composite reference standards (CRSs) have been advocated in this diagnostic study. This study assesses the agreement between traditional diagnostic modalities using CRS and prevalent TB groups among different fallopian tube infertility manifestations. A total of 86 women with primary and secondary infertility were included in the study and subjected to bacteriological, pathological, and radiological examination for the diagnosis of FGTB. Results were evaluated statistically for concordance of the diagnostic tests to the CRS by sensitivity and specificity, while PPV and NPV were calculated for the performance of diagnostic tests of FGTB. We observed that 11.2% of women were found to be true positives by means of CRS. The positive findings by CRS were as follows: ultrasonography (13.9%), laparoscopy (14%), hysteroscopy (12%), GeneXpert (4.8%), culture (4.8%), polymerase chain reaction (4.8%), and histopathology (6.4%). GeneXpert and culture were found to have a perfect agreement with CRS. Hysterosalpingography, laparoscopy, and hysteroscopy have a fair agreement with CRS. Out of 43 women with tubal factor infertility, 6 women were found in the definitive TB group with mixed conditions of tubal manifestations. This study evaluates and demonstrates the reliability of the collective assessment of various diagnostic methods with CRS findings that help in identifying different TB groups of genital tuberculosis patients from all infertile patients by applying the criteria of CRS.

Heterozygous loss-of-function variants in LHX8 cause female infertility characterized by oocyte maturation arrest.

PURPOSE: The genetic causes of oocyte maturation arrest leading to female infertility are largely unknown, and no population-based genetic analysis has been applied in cohorts of patients with infertility. We aimed to identify novel pathogenic genes causing oocyte maturation arrest by using a gene-based burden test. METHODS: Through comparison of exome sequencing data from 716 females with infertility characterized by oocyte maturation arrest and 3539 controls, we performed a gene-based burden test and identified a novel pathogenic gene LHX8. Splicing event was evaluated using a minigene assay, expression of LHX8 protein was assessed in HeLa cells, and nuclear subcellular localization was determined in both HeLa cells and mouse oocytes. RESULTS: A total of 5 heterozygous loss-of-function LHX8 variants were identified from 6 independent families (c.389+1G>T, c.412C>T [p.Arg138∗], c.282C>A [p.Cys94∗]; c.257dup [p.Tyr86∗]; and c.180del, [p.Ser61Profs∗30]). All the identified variants in LHX8 produced truncated LHX8 protein and resulted in loss of LHX8 nuclear localization in both HeLa cells and mouse oocytes. CONCLUSION: By combining genetic evidence and functional evaluations, we identified a novel pathogenic gene LHX8 and established the causative relationship between LHX8 haploinsufficiency and female infertility characterized by oocyte maturation arrest.

A novel heterozygous variant in PANX1 is associated with oocyte death and female infertility.

PURPOSE: Oocyte death is a severe clinical phenotype that causes female infertility and recurrent in vitro fertilization and intracytoplasmic sperm injection failure. We aimed to identify pathogenic variants in a female infertility patient with oocyte death phenotype. METHODS: Sanger sequencing was performed to screen PANX1 variants in the affected patient. Western blot analysis was used to check the effect of the variant on PANX1 glycosylation pattern in vitro. RESULTS: We identified a novel PANX1 variant (NM_015368.4 c.86G > A, (p. Arg29Gln)) associated with the phenotype of oocyte death in a non-consanguineous family. This variant displayed an autosomal dominant inheritance pattern with reduced penetrance. Western blot analysis confirmed that the missense mutation of PANX1 (c.86G > A) altered the glycosylation pattern in HeLa cells. Moreover, the mutation effects on the function of PANX1 were weaker than recently reported variants. CONCLUSION: Our findings expand the inheritance pattern of PANX1 variants to an autosomal dominant mode with reduced penetrance and enrich the variational spectrum of PANX1. These results help us to better understand the genetic basis of female infertility with oocyte death.

Research update for the immune microenvironment of chronic endometritis.

Chronic endometritis (CE) is a persistent and subtle local inflammatory disease characterized by abnormal plasma cell infiltration in the endometrial stroma.The incidence of chronic endometritis is as high as 15-57.5% in women suffering from infertility, implantation failure of in vitro fertilization (IVF) and unexplained recurrent abortion. Many studies both at home and abroad have shown that CE can reduce the receptivity of endometrium and affect embryo implantation. According to the existing reproductive immunity research, the abnormality of immune cell subsets in endometrium is an important factors leading to pregnancy failure. The immune microenvironment in endometrium consists of immune cells and immune molecules, and their influence on embryo implantation can not be ignored. This review paper discusses the controversy of pathogenesis, diagnosis and treatment of CE from the perspective of immune microenvironment by referring to related literature at home and abroad, and investigates the possible ways to improve the diagnosis and treatment of CE.