Immunological changes associated with adenomyosis: a systematic review

Eutopic and Ectopic Endometrial Interleukin-17 and Interleukin-17 Receptor Expression at the Endometrial-Myometrial Interface in Women with Adenomyosis: Possible Pathophysiology Implications

Adenomyosis involves the infiltration of endometrial glands and stroma deep into the uterine tissue, causing disruption to the endometrial-myometrial interface (EMI). The role of interleukin-17 (IL-17) has been extensively studied in endometriosis, but its involvement in adenomyosis remains unclear. This study aimed to investigate the expression of IL-17 in eutopic and ectopic endometrium (adenomyosis) of individuals with adenomyosis at the level of EMI. Paired tissues of eutopic endometrium and adenomyoma were collected from 16 premenopausal women undergoing hysterectomy due to adenomyosis. The IL-17 system was demonstrated in paired tissue samples at the level of EMI by the immunochemistry study. Gene expression levels of IL-17A and IL-17 receptor (IL-17R) were assessed through quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). Comparative gene transcript amounts were calculated using the delta-delta Ct method. By immunohistochemical staining, CD4, IL-17A, and IL-17R proteins were detected in both eutopic endometrium and adenomyosis at the level of EMI. IL-17A and IL-17R were expressed mainly in the glandular cells, and the expression of both IL-17A and IL-17R was found to be stronger in adenomyosis than in endometrium. 3-Diaminobenzidine (DAB) staining revealed greater IL-17A expression in adenomyosis compared to eutopic endometrium. Quantitative RT-PCR showed 7.28-fold change of IL-17A and 1.99-fold change of IL-17R, and the fold change level of both IL-17A and IL-17R is significantly higher in adenomyosis (IL-17A: p = 0.047, IL-17R: p = 0.027) versus eutopic endometrium. We found significantly higher IL-17 levels in adenomyosis compared to eutopic endometrium at the level of EMI. The results showed that the IL-17 system may play a role in adenomyosis.

Comprehensive analysis of circRNA-miRNA-mRNA regulatory network and novel potential biomarkers in eutopic endometrium of adenomyosis

Adenomyosis (ADS) is a common gynecological disorder, and its pathogenesis remains unclear. This study explores the functions of circRNAs in the eutopic endometrium of ADS and their diagnostic efficacy for ADS. High-throughput RNA sequencing was performed on 12 eutopic endometrial samples from ADS patients and 3 control endometrial samples. Additionally, circRNAs were analyzed in conjunction with clinical features. A competitive endogenous RNA network was established based on bioinformatics analysis, comprising 3 circRNAs, 1 miRNA, and 13 mRNAs. In the ADS group, the expression levels of hsa_circ_0008959 and SLC15A4 were significantly reduced, while hsa-miR-124-3p expression was increased. SLC15A4 was associated with cell proliferation and invasion. Decreased expression of hsa_circ_0008959 and SLC15A4, along with high VAS scores and elevated hsa-miR-124-3p levels, were identified as risk factors for ADS development. The combination of hsa_circ_0008959 and VAS scores demonstrated the highest diagnostic value for ADS.

Overview of crosstalk between stromal and epithelial cells in the pathogenesis of adenomyosis and shared features with deep endometriotic nodules

Since the first description of adenomyosis more than 150 years ago, multiple hypotheses have attempted to explain its pathogenesis. Indeed, research over recent years has greatly enhanced our knowledge of the underlying causes. This has opened up avenues for the development of strategies for both disease prevention and treatment of its main symptoms, such as pelvic pain, heavy menstrual bleeding, and infertility. However, the current means are still largely ineffective, so it is vital that we shed light on the pathways involved. Dysregulated mechanisms and aberrant protein expression have been identified as contributing factors in interactions between endometrial epithelial and stromal cells, ultimately leading to the growth of adenomyotic lesions. These include collective cell migration, epithelial-to-mesenchymal transition, hormonal influence, and signaling from non-coding RNAs and extracellular vesicles. We provide a concise summary of the latest insights into the crosstalk between glands and stroma in ectopic adenomyotic lesion formation. While there is an abundance of literature on similarities between adenomyosis and deep endometriosis, there are insufficient data on the cytochemical, molecular, and pathogenetic mechanisms of these two disorders. However, various shared features, including alterations of cell adhesion molecules, abnormal hormone regulation, and the presence of cancer-driving mutations and epigenetic modifications, have been identified. Nevertheless, the pathogenic mechanisms that contribute to the cause and development of these enigmatic diseases have not been fully elucidated yet.

Prevalence and risk factors for chronic endometritis in patients with adenomyosis and infertility: a retrospective cohort study

BACKGROUND

To explore the incidence of chronic endometritis (CE) in patients with infertility and different forms of adenomyosis and analyze potential high-risk factors for infection.

METHODS

This retrospective cohort study included 154 patients with infertility in the Liuzhou Maternity and Child Healthcare Hospital. Among them, 77 patients with adenomyosis were divided into four subgroups based on magnetic resonance imaging (MRI): internal, exterior, intramural, and full-thickness. Meanwhile, 77 patients did not have adenomyosis. Hysteroscopy and endometrial biopsy were performed in the proliferative phase. The main outcome measures were the morphology of the endometrium, syndecan-1 (CD138) immunohistochemical staining, clinical characteristics, and prevalence of CE in the adenomyosis subgroups.

RESULTS

In comparison to the non-adenomyosis group, the adenomyosis group had significantly higher body mass index (BMI) and CA125 levels. The menstrual cycle in the adenomyosis group was significantly shorter, and menarche was significantly earlier. In comparison to the non-adenomyosis group, the adenomyosis group had a significantly higher diagnostic rate of CE (75.3% vs. 46.8% according to hysteroscopy and 74.0% vs. 33.8% according to histopathology, both with p < .050). The incidence of CE was significantly lower in patients with internal adenomyosis when compared with the other three subgroups. Increased BMI contributed to a higher risk of CE.

CONCLUSIONS

The prevalence of CE was significantly higher in patients with adenomyosis and infertility. The differences in the incidence of CE are closely associated with the classification of adenomyosis. When patients with infertility are diagnosed with adenomyosis, it is recommended to identify the subtype and screen for endometritis.

Comprehensive transcriptional atlas of human adenomyosis deciphered by the integration of single-cell RNA-sequencing and spatial transcriptomics

Adenomyosis is a poorly understood gynecological disorder lacking effective treatments. Controversy persists regarding "invagination" and "metaplasia" theories. The endometrial-myometrial junction (EMJ) connects the endometrium and myometrium and is important for diagnosing and classifying adenomyosis, but its in-depth study is just beginning. Using single-cell RNA sequencing and spatial profiling, we mapped transcriptional alterations across eutopic endometrium, lesions, and EMJ. Within lesions, we identified unique epithelial (LGR5+) and invasive stromal (PKIB+) subpopulations, along with WFDC1+ progenitor cells, supporting a complex interplay between "invagination" and "metaplasia" theories of pathogenesis. Further, we observed endothelial cell heterogeneity and abnormal angiogenic signaling involving vascular endothelial growth factor and angiopoietin pathways. Cell-cell communication differed markedly between ectopic and eutopic endometrium, with aberrant signaling in lesions involving pleiotrophin, TWEAK, and WNT cascades. This study reveals unique stem cell-like and invasive cell subpopulations within adenomyosis lesions identified, dysfunctional signaling, and EMJ abnormalities critical to developing precise diagnostic and therapeutic strategies.

Cytotoxic T Lymphocytes, Tc17 Cells, Th1 Cells, and ThGM Cells are Increased in the Blood and Ectopic Endometrium of Patients With Adenomyosis

PROBLEM

Adenomyosis (AM) is associated with immune response and inflammation. However, the role of T cell subsets in AM development has not been thoroughly understood.

METHOD OF STUDY

Patients with focal or diffuse AM were recruited. Serum cytokines were quantified by enzyme-linked immunosorbent assay (ELISA). Different T cell subsets in the blood and ectopic endometrium were determined by flow cytometry.

RESULTS

Serum interleukin-6 (IL-6) and macrophage-colony-stimulating factor (GM-CSF) were increased in patients with focal or diffuse AM before focused ultrasound ablation surgery (FUAS), but not after FUAS. Compared with the healthy control, the frequencies of CD8+ interferon-gamma (IFN-γ)-expressing cytotoxic T lymphocytes (CTLs), interleukin-17A (IL-17A)-expressing Tc17 cells, CD4+ T helper 1 (Th1) cells, and GM-CSF-expressing T helper (ThGM) cells were up-regulated in the blood of patients with AM, especially those with diffuse AM. However, these changes were eradicated after FUAS. Meanwhile, the frequencies of these T cell subsets were positively correlated with the CA-125 level. Furthermore, these T cell subsets were also increased in ectopic endometrium.

CONCLUSIONS

Our study delineates for the first time the presence of CTLs, Tc17 cells, Th1, and ThGM cells in the blood and ectopic endometrium in AM. The results imply that T cell response might impact AM development.

Comparative analysis of endometrial, vaginal, and gut microbiota in patients with and without adenomyosis

INTRODUCTION

Alterations in microbiota composition have been implicated in a variety of human diseases. Patients with adenomyosis present immune dysregulation leading to a persistent chronic inflammatory response. In this context, the hypothesis that alterations in the microbiota may be involved in the pathogenesis of adenomyosis, by affecting the epigenetic, immunologic, and biochemical functions of the host, has recently been postulated. The aim of the present study was to compare the microbiota composition in the vagina, endometrium, and gut of individuals with and without adenomyosis.

MATERIAL AND METHODS

Cross-sectional study including 38 adenomyosis patients and 46 controls, performed between September 2021 and October 2022 in a university hospital-based research center. The diagnosis of adenomyosis was based on sonographic criteria. Fecal, vaginal, and endometrial samples were collected. Study of the microbiota using 16S rRNA gene sequencing.

RESULTS

Patients with adenomyosis exhibited a significant reduction in the gut microbial alpha diversity compared with healthy controls (Chao1 p = 0.012, Fisher p = 0.005, Observed species p = 0.005). Beta-diversity analysis showed significant differences in the compositions of both gut and vaginal microbiota between adenomyosis patients and the control group (Adonis p-value = 0.001; R2 = 0.03 and Adonis p-value = 0.034; R2 = 0.04 respectively). Specific bacterial taxa were found to be either overrepresented (Rhodospirillales, Ruminococcus gauvreauii group, Ruminococcaceae, and Actinomyces) or underrepresented in the gut and endometrial microbiota of adenomyosis patients compared with controls. Distinct microbiota profiles were identified among patients with internal and external adenomyosis phenotypes.

CONCLUSIONS

The study revealed reduced gut microbiota diversity in adenomyosis patients, accompanied by distinct compositions in gut and vaginal microbiota compared with controls. Overrepresented or underrepresented bacterial taxa were noted in the gut and endometrial microbiota of adenomyosis patients, with variations in microbiota profiles among those with internal and external adenomyosis phenotypes. These findings suggest a potential association between microbiota and adenomyosis, indicating the need for further research to comprehensively understand the implications of these differences.

Imaging and molecular features of adenomyosis after menopause

OBJECTIVES

To explore the imaging features and the molecular characterization of adenomyosis after menopause.

STUDY DESIGN

An observational cross-sectional study was performed in a group of postmenopausal patients undergoing a transvaginal ultrasound (TVUS) (n = 468). Among those presenting the US criteria for adenomyosis, also confirmed by magnetic resonance imaging (MRI), previous menstrual symptoms, gynecological and obstetric history were reviewed. In a subgroup undergoing hysterectomy, uterine specimens were analyzed by histology and expression of genes implicated in the epithelial-mesenchymal transition, inflammation and fibrosis, including the sphingosine-1-phosphate (S1P) pathway, was evaluated and compared to matched non-menopausal adenomyosis specimens.

MAIN OUTCOME MEASURES

Direct and indirect US features of adenomyosis according to Morphological Uterus Sonographic Assessment at TVUS. Molecular characterization of postmenopausal versus pre-menopausal adenomyosis samples.

RESULTS

According to TVUS and MRI, adenomyosis was identified in 49 patients (10.4 %). On US, diffuse adenomyosis was the most common phenotype, whereas internal adenomyosis with diffuse pattern and asymmetric type was the most prevalent on MRI. Molecular analysis showed that adenomyosis lesions express markers of epithelial-mesenchymal transition, inflammation and fibrosis also in postmenopausal women. By comparing the results with those from pre-menopausal samples, the expression of α smooth muscle actin (αSMA), a marker of fibrosis, was significantly greater after menopause, and altered S1P catabolism and signaling were observed.

CONCLUSIONS

Adenomyosis may be identified in postmenopausal women by imaging, either TVUS or MRI, and fibrosis is one of the key features on molecular analysis.

The Impacts of Inflammatory and Autoimmune Conditions on the Endometrium and Reproductive Outcomes

Background: A healthy pregnancy begins with an adequate endometrial state, even before the arrival of a blastocyst. Proper endometrial priming and the development of a tolerogenic decidua are key steps in creating the perfect environment for implantation and pregnancy. In these processes, the involvement of the maternal immune system seems to be of great relevance, modulating the different decidual immune populations to prepare the endometrium for a potential pregnancy. However, certain local pathologies of an inflammatory and autoimmune nature appear to have a direct impact on these phenomena, thus altering patients' reproductive outcomes. Methods: This literature review analyzes original articles, reviews, systematic reviews, and meta-analyses published between 1990 and 2024, concerning the impact of different inflammatory and autoimmune conditions on endometrial status and fertility. The included papers were obtained from Medline (Pubmed) and the Cochrane library. Results: There is evidence that endometriosis, adenomyosis, and chronic endometritis, through the promotion of a chronic inflammatory environment, are capable of altering endometrial immune populations, and, thus, processes essential for early pregnancy. Among other effects, these conditions have been linked to impaired decidualization, alterations in progesterone responsiveness, and hindered placentation. Similarly, antiphospholipid syndrome (APS), thyroid dysfunction, diabetes, and other pathologies related to glucose and gluten metabolism, due to their autoimmune nature, also appear to have a local impact on the uterine environment, affecting reproductive success through different mechanisms, including altered hormonal response and, again, impaired decidualization. Conclusions: The management of inflammatory and autoimmune diseases in assisted reproduction patients is gaining importance due to their direct impact on the endometrium. It is necessary to follow current expert recommendations and established therapeutic approaches in order to improve patients' prospects, ranging from antibiotic treatment in chronic endometritis to heparin and aspirin in APS, as well as hormonal treatments for endometriosis/adenomyosis or a gluten-free diet in celiac disease. All of them and the rest of the therapeutic perspectives, both current and under investigation, are presented throughout this work, assessing the possible improvements for reproductive outcomes.

The pathogenesis of endometriosis and adenomyosis: insights from single-cell RNA sequencing†

Endometriosis and adenomyosis are two similar gynecological diseases that are characterized by ectopic implantation and the growth of the endometrial tissue. Previous studies have reported that they share a common pathophysiology in some respects, such as a similar cellular composition and resistance to the progestogen of lesions, but their underlying mechanisms remain elusive. Emerging single-cell ribonucleic acid sequencing (scRNA-seq) technologies allow for the dissection of single-cell transcriptome mapping to reveal the etiology of diseases at the level of the individual cell. In this review, we summarized the published findings in research on scRNA-seq regarding the cellular components and molecular profiles of diverse lesions. They show that epithelial cell clusters may be the vital progenitors of endometriosis and adenomyosis. Subclusters of stromal cells, such as endometrial mesenchymal stem cells and fibroblasts, are also involved in the occurrence of endometriosis and adenomyosis, respectively. Moreover, CD8+ T cells, natural killer cells, and macrophages exhibit a deficiency in clearing the ectopic endometrial cells in the immune microenvironment of endometriosis. It seems that the immune responses are activated in adenomyosis. Understanding the immune characteristics of adenomyosis still needs further exploration. Finally, we discuss the application of findings from scRNA-seq for clinical diagnosis and treatment. This review provides fresh insights into the pathogenesis of endometriosis and adenomyosis as well as the therapeutic targets at the cellular level.

Macrophage polarization in adenomyosis: A review

Adenomyosis (AM) is a common gynecological disorder characterized by the presence of endometrial glands and stroma within the uterine myometrium. It is associated with abnormal uterine bleeding (AUB), dysmenorrhea, and infertility. Although several mechanisms have been proposed to elucidate AM, the exact cause and development of the condition remain unclear. Recent studies have highlighted the significance of macrophage polarization in the microenvironment, which plays a crucial role in AM initiation and progression. However, a comprehensive review regarding the role and regulatory mechanism of macrophage polarization in AM is currently lacking. Therefore, this review aims to summarize the phenotype and function of macrophage polarization and the phenomenon of the polarization of adenomyosis-associated macrophages (AAMs). It also elaborates on the role and regulatory mechanism of AAM polarization in invasion/migration, fibrosis, angiogenesis, dysmenorrhea, and infertility. Furthermore, this review explores the underlying molecular mechanisms of AAM polarization and suggests future research directions. In conclusion, this review provides a new perspective on understanding the pathogenesis of AM and provides a theoretical foundation for developing targeted drugs through the regulation of AAM polarization.

Extracellular vesicle-encapsulated miR-25-3p promotes epithelial-mesenchymal transition and migration of endometrial epithelial cells by inducing macrophage polarization

The pathogenesis of adenomyosis is closely related to the epithelial-mesenchymal transition and macrophages. MicroRNAs have been extensively investigated in relation to the epithelial-mesenchymal transition in a range of malignancies. However, there is a paucity of research on extracellular vesicles derived from the eutopic endometrium of adenomyosis and their encapsulated microRNAs. In this study, we investigated the role of microRNA-25-3p derived from extracellular vesicles in inducing macrophage polarization and promoting the epithelial-mesenchymal transition in endometrial epithelial cells of patients with adenomyosis and controls. We obtained eutopic endometrial samples and isolated extracellular vesicles from the culture supernatant of primary endometrial cells. Real-time quantitative PCR analysis demonstrated that microRNA-25-3p was highly expressed in extracellular vesicles, as well as in macrophages stimulated by extracellular vesicles from eutopic endometrium of adenomyosis; and macrophages transfected with microRNA-25-3p exhibited elevated levels of M2 markers, while displaying reduced levels of M1 markers. After co-culture with the above polarized macrophages, endometrial epithelial cells expressed higher levels of N-cadherin and Vimentin, and lower protein levels of E-cadherin and Cytokeratin 7. It was revealed that microRNA-25-3p encapsulated in extracellular vesicles from eutopic endometrial cells could induce macrophage polarization toward M2, and the polarized macrophages promote epithelial-mesenchymal transition in epithelial cells. However, in vitro experiments revealed no significant disparity in the migratory capacity of endometrial epithelial cells between the adenomyosis group and the control group. Furthermore, it was observed that microRNA-25-3p-stimulated polarized macrophages also facilitated the epithelial-mesenchymal transition and migration of endometrial epithelial cells within the control group. Thus, the significance of microRNA-25-3p-induced polarized macrophages in promoting the development of adenomyosis is unclear, and macrophage infiltration alone may be adequate for this process. We emphasize the specificity of the local eutopic endometrial microenvironment and postulate its potential significance in the pathogenesis of adenomyosis.

The "freeze-all" strategy seems to improve the chances of birth in adenomyosis-affected women

OBJECTIVE

To compare assisted reproductive technologies (ARTs) outcomes between fresh vs. freeze-all strategies in infertile women affected by adenomyosis.

DESIGN

A single-center observational study.

SETTINGS

University hospital-based research center.

PATIENTS

Adenomyosis-affected women undergoing blastocyst embryo transfer after in vitro fertilization and intracytoplasmic sperm injection between January 1, 2018, and November 31, 2021. The diagnosis of adenomyosis was based on imaging criteria (i.e., transvaginal ultrasound and/or magnetic resonance imaging).

INTERVENTION(S)

Women who underwent a freeze-all strategy were compared with those who underwent a fresh embryo transfer (ET) strategy.

MAIN OUTCOME MEASURE(S)

Cumulative live birth rate (LBR).

RESULTS

A total of 306 women were included in the analysis: 111 in the fresh ET group and 195 in the freeze-all group. The adenomyosis phenotype (internal diffuse adenomyosis, external focal adenomyosis, and adenomyoma) was not significantly different between the two groups. The cumulative LBR (86 [44.1%] vs. 34 [30.6%], respectively), and the cumulative ongoing pregnancy rate (88 [45.1%] vs. 36 [32.4%], respectively) were significantly higher in the freeze-all group compared with the fresh ET group. After multivariate logistic regression analysis, the freeze-all strategy in women with adenomyosis was associated with significantly higher odds of live birth compared with fresh ET (odds ratio = 1.80; 95% confidence interval = 1.02-3.16).

CONCLUSION

The freeze-all strategy in women afflicted with adenomyosis undergoing ART was associated with significantly higher cumulative LBRs. Our preliminary results suggest that the freeze-all strategy is an attractive option that increases ART success rates. Additional studies, with a randomized design, should be conducted to further test whether the freeze-all strategy enhances the pregnancy rate in adenomyosis-affected women.

Endometriosis and adenomyosis: Similarities and differences

Deep endometriosis and uterine adenomyosis are two frequently encountered conditions affecting approximately 200 million women worldwide. They are closely related, showing similar histological patterns and multiple common pathogenic features, and share the same symptoms. It is therefore not surprising that they are often thought to have a common developmental origin. Indeed, both deep endometriosis and adenomyosis appear to derive from estrogen-dependent overproliferation of endometrial tissue and its subsequent implantation in ectopic sites. Although the scientific community has shown increasing interest in these diseases over recent years, neither pathogenesis has yet been elucidated, so there are currently no efficient treatment options. Understanding the mechanisms underlying disease development, as well as discerning their relationship, are key to improving clinical management for millions of patients. The aims of this review are to summarize current knowledge on deep endometriosis and adenomyosis pathogeneses and discuss the possibility that these two entities are actually differential phenotypes of the same disease.

Proteomic detection of COX-2 pathway-related factors in patients with adenomyosis

Background

Investigating the relationship between cyclooxygenase-2 (COX-2) pathway-related factors and clinical features in patients with adenomyosis by proteomics could provide potential therapeutic targets.

Methods

This study recruited 40 patients undergoing surgical hysterectomy and pathological diagnosis of adenomyosis, collected ectopic endometrial specimens, and recorded clinical data. The expression levels of COX-2 in ectopic uterus lesions were detected using the immunohistochemical (IHC) SP method. The 40 samples were then divided into a COX-2 low or high expression group. Five samples with the most typical expression levels were selected from each of the two groups and the differential proteins between the two groups were identified using label-free quantitative proteomics. WW domain-binding protein 2 (WBP2), interferon induced transmembrane protein 3 (IFITM3), and secreted frizzled-related protein 4 (SFRP4) were selected for further verification, and their relationships with COX-2 and clinical characteristics were analyzed.

Results

There were statistically significant differences in the expression of WBP2, IFITM3, and SFRP4 between the COX-2 low and high expression groups (P < 0.01). The expressions of COX-2, IFITM3, and SFRP4 were significantly correlated with dysmenorrhea between the two groups (P < 0.05), but not with uterine size or menstrual volume (P > 0.05). However, there was no significant correlation between the expression of WBP2 and dysmenorrhea, uterine size, and menstruation volume in both the high expression and low expression groups (P > 0.05).

Conclusions

COX-2, IFITM3, SFRP4, and WBP2 may be involved in the pathogenesis of adenomyosis. COX-2, IFITM3, and SFRP4 may serve as potential molecular biomarkers or therapeutic targets in dysmenorrhea in patients with early adenomyosis.

Reduced fertility in an adenomyosis mouse model is associated with an altered immune profile in the uterus during the implantation period

STUDY QUESTION

Does a reduction in fertility and/or systemic immune cell change occur during the early implantation period in a mouse model of adenomyosis?

SUMMARY ANSWER

A reduction in fertility was observed in mice with adenomyosis, coinciding with local and systemic immune changes observed during the implantation period.

WHAT IS KNOWN ALREADY

Adenomyosis is a pathology responsible for impaired fertility in humans, with a still unclear pathophysiology. One hypothesis is that changes in immune cells observed in adenomyosis-affected uteri may alter fertility, notably the physiological immune environment necessary for successful implantation and a healthy pregnancy.

STUDY DESIGN, SIZE, DURATION

Randomly selected CD-1 female neonatal pups were orally dosed by administration of tamoxifen to induce adenomyosis (TAM group), while others received solvent only (control group). From 6 weeks of life, CD-1 mice of both groups were mated to study impaired fertility and related local and/or systemic immune cell changes during the early implantation period.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

To evaluate fertility and pregnancy outcomes, ultrasound imaging was performed at E (embryonic day) 7.5 and E11.5 to count the number of gestational sacs and the number of resorptions in eight mice of the TAM group and 16 mice of the control group. The mice were sacrificed at E18.5, and morphometric, functional (quantitative reverse transcription PCR; RT-qPCR), and histological analyses were performed on the placentas. To identify local and/or systemic immune changes during the early implantation period, 8 mice of the TAM group and 12 mice of the control group were sacrificed at E4.5. Uterine horns and spleens were collected for flow cytometry and RT-qPCR analyses to study the immune cell populations. To investigate the profile of the cytokines secreted during the early implantation period at the systemic level, supernatants from stimulated spleen cells were analyzed by multiplex immunoassay analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

By ultrasound imaging, we observed a lower number of implantation sites (P < 0.005) and a higher number of resorptions (P < 0.001) in the TAM group, leading to smaller litters (average number of fetuses per litter: 1.00 [0.00; 5.25] in the TAM group versus 12.00 [9.50; 13.75] in the control group (P < 0.001). Histological and morphometric analyses of the placentas at E18.5 showed a higher junctional/labyrinthine area ratio in the TAM group (P = 0.005). The expression levels of genes that play a role in vascularization and placental growth (Vegf (P < 0.001), Plgf (P < 0.005), Pecam (P < 0.0001), and Igf2 (P = 0.002)) were reduced in the TAM group. In the TAM group, the percentages of macrophages, natural killer (NK) cells, and dendritic cells (DC) were significantly decreased in the uterus around the implantation period. However, the number of M1 macrophages was increased. Both macrophages and DC had an increased activation profile (higher expression of MCHII, P = 0.012; CD80, P = 0.015; CCR7, P = 0.043 for macrophages, and higher expression of CD206, P = 0.018; CXCR4, P = 0.010; CCR7, P = 0.006, MCHII, P = 0.010; and CD80, P = 0.012 for DC). In spleen, an increase in the activation of macrophages (CCR7, P = 0.002; MCHII, P = 0.001; and CD80, P = 0.034) and DC was observed in the TAM group (CCR7, P = 0.001; MCHII, P = 0.001; Ly6C, P = 0.015). In the uteri and the spleen, we observed increased percentages of CD4+ T lymphocytes (P = 0.0237 and P = 0.0136, respectively) in the TAM group and, in the uteri, an increased number of regulatory T cells (P = 0.036) compared with the controls.

LARGE SCALE DATA

Not applicable.

LIMITATIONS, REASONS FOR CAUTION

This study is limited by the use of an animal model and the lack of intervention.

WIDER IMPLICATIONS OF THE FINDINGS

These data support involvement of innate and adaptive immune cells in the implantation failure and the increased rate of resorption observed in the mouse model of adenomyosis. This substantiates the need for additional research in this domain, with the goal of addressing fertility challenges in women affected by this condition.

STUDY FUNDING/COMPETING INTEREST(S)

None.

Expression of high-mobility group box-1 in eutopic/ectopic endometrium and correlations with inflammation-related factors in adenomyosis

OBJECTIVE

To investigate the expression of HMGB1 and toll-like receptor 4 (TLR4) in adenomyosis eutopic/ectopic endometrium.

METHODS

Twenty patients with adenomyosis and 20 controls, all undergoing laparoscopy, were recruited from September 2015 to July 2016. Samples were collected from the endometrium without adenomyosis (CE), the eutopic endometrium with adenomyosis (EuE), and the ectopic endometrium with adenomyosis (EE). The mRNA and protein expression of HMGB1 and TLR4, and interleukin-6 (IL-6) and interleukin-8 (IL-8) RNA expression levels were measured.

RESULTS

The average age of the adenomyosis women was 43.4 ± 5.3 years; their BMI was 23.3 ± 2.3 kg/m2. The control group included women aged 38.8 ± 9.8 years, with BMI 22.2 ± 3.4 kg/m2. The mRNA expression levels of HMGB1, TLR4, IL-6, and IL-8 in the EE and EuE groups were higher than those in the CE group (p < .01), and those in the EE group were higher than those in the EuE group (p < .01). The protein expression levels of HMGB1 and TLR4 in the EE and EuE groups were higher than those in the CE group (p < .01); they were higher in the EE group than the ones in the EuE group (p < .01). HMGB1 mRNA was significantly positively correlated with TLR4 in EuE and EC patients (r = 0.538 and r = 0.916, p < .01), as well as with IL-6 (r = 0.470 and r = 0.976, p < .01) and IL-8 (r = 0.574 and r = 0.650, p < .01).

CONCLUSIONS

The overexpression of HMGB1 and TLR4 in EuE and EE is positively correlated with IL-6 and IL-8 expression. The HMGB1 signaling-mediated immune-inflammatory system might be involved in the development of adenomyosis.

Abnormal Uterine Bleeding in Reproductive Age Women: Role of Imaging in the Diagnosis and Management

Abnormal uterine bleeding (AUB) is defined by the International Federation of Gynecology and Obstetrics as bleeding from the uterine corpus that is abnormal in regularity, volume, frequency, or duration and occurs in the absence of pregnancy. AUB is a common condition that affects about a third of women in their lifetime. Abnormal bleeding in duration, quantity, or timing consists of 2 categories, predictable cyclical heavy menstrual bleeding (HMB) and irregular non-cyclical intermenstrual bleeding (IMB). The most common causes of HMB include fibroids and adenomyosis and IMB is commonly caused by ovulatory dysfunction such as in polycystic ovaries, endometrial polyp, or an IUD. A pelvic ultrasound is the initial and often only imaging modality needed in the imaging evaluation of abnormal uterine bleeding and can accurately identify the common causes of abnormal uterine bleeding in the reproductive age group.

Increased chemokine ligand 26 expression and its involvement in epithelial-mesenchymal transition in the endometrium with adenomyosis

OBJECTIVE

Adenomyosis is a gynecologic disorder characterized by symptoms of dysmenorrhea, abnormal uterine bleeding, and infertility. This study aimed to analyze the expression profiles of key inflammatory cytokines in the endometrium with adenomyosis and their involvement in epithelial-mesenchymal transition (EMT).

STUDY DESIGN

Endometrial tissues collected from premenopausal women with (n = 3) or without (n = 3) adenomyosis during the secretory phase were subjected to DNA array analysis to examine inflammatory cytokines. The gene and protein expression levels were re-evaluated by reverse transcription-polymerase chain reaction (n = 19) and immunohistochemistry (n = 56). Immunohistochemical analysis using the Histo-scores of chemokine ligand 26 (CCL26) and EMT-related factors was performed with uterine tissues resected for adenomyosis (n = 37), including those from patients treated with gonadotropin-releasing hormone agonist (GnRHa). An invasion assay was also performed using endometrial epithelial cells.

RESULTS

DNA array results showed that CCL26, IL-1B, and CCL3 were upregulated. CCL26 mRNA expression was markedly higher in the endometrium with adenomyosis than in that without adenomyosis. Immunohistochemical analysis revealed that CCL26 expression was elevated in the epithelial cells of the basal layer of the endometrium with adenomyosis than in that without adenomyosis regardless of GnRHa treatment. In the basal layer of the endometrium with adenomyosis, CCL26 expression was positively correlated with neural-cadherin and ZEB1 expression; additionally, the cases with intrinsic-type adenomyosis had high expression levels of CCL26 and ZEB1. Exogenous CCL26 promoted the invasive activity of endometrial epithelial cells.

CONCLUSIONS

CCL26, an inflammatory mediator, may be involved in the pathogenesis of adenomyosis by inducing EMT in the basal layer of the endometrium.

Endometrial cell‑derived exosomes facilitate the development of adenomyosis via the IL‑6/JAK2/STAT3 pathway

Interleukin (IL)-6 upregulation is involved in the pathogenesis of adenomyosis, but the underlying mechanism remains to be elucidated. Exosomes mediate intercellular communication, therefore the present study investigated whether endometrial cell-derived exosomes mediated the crosstalk between the endometrium and the myometrium via IL-6 signaling. Primary adenomyotic myometrial (AM) cells and eutopic endometrial cells were isolated from patients with adenomyosis. Exosomes were obtained from endometrial cells and incubated with AM cells in the presence or absence of tocilizumab (an IL-6 inhibitor). MTT, flow cytometry and wound-healing assays were performed to examine AM cell proliferation, apoptosis, cell cycle distribution and migration. Western blotting and reverse transcription-quantitative PCR were conducted to determine the expression of the IL-6/Janus kinase 2 (JAK2)/STAT3 pathway proteins. Incubation with endometrial cell exosomes suppressed cell apoptosis of AM cells compared with controls, accompanied by increases in IL-6 production and JAK2/STAT3 phosphorylation. Endometrial cell exosomes promoted cell proliferation, increased the percentage of S-phase cells and enhanced the migration of AM cells. These effects were completely reversed by tocilizumab, along with substantial decreases in IL-6 production and JAK2/STAT3 phosphorylation. Endometrial cell-derived exosomes promote cell proliferation, migration and cell cycle transition of AM cells through IL-6/JAK2/STAT3 activation, facilitating the development of adenomyosis by mediating the crosstalk between the endometrium and the myometrium, and IL-6 targeted therapy could be a complementary approach against adenomyosis.

Serum CA125 as a biomarker for dysmenorrhea in adenomyosis

OBJECTIVE

To explore the association between CA125 and dysmenorrhea in adenomyosis, and the factors affecting CA125 in adenomyosis.

METHODS

Patients were grouped a the presence of dysmenorrhea. The receiver operating characteristic (ROC) curve was applied to assess the utility of CA125 for dysmenorrhea. Binary logistic regression was employed to identify the factors associating dysmenorrhea and CA125 level.

RESULTS

Patients in the dysmenorrhea group had higher CA125 levels than those in the non-dysmenorrhea group. For those with dysmenorrhea, CA125 levels of diffuse subtype group were higher than those of the focal subtype group. The CA125 level of 35 U/mL was validated as the optimal cut-point for dysmenorrhea in ROC curves. Compared with patients whose CA125 was 35 U/mL or less, those with CA125 levels greater than 35 U/mL were more likely to have dysmenorrhea. Thereafter, the multiple regression analysis showed that adenomyotic lesion volume was positively correlated with CA125 level in the total cohort and subtype groups, while age was negatively correlated with CA125 level in the total cohort and diffuse subtype.

CONCLUSIONS

The pathogenesis of adenomyosis is not clear. CA125 was associated with dysmenorrhea in adenomyosis, and, furthermore, CA125 level is positively correlated with the severity of the disease.

Exosomes: potential diagnostic markers and drug carriers for adenomyosis

Adenomyosis is a common benign gynecological disorder and an important factor leading to infertility in fertile women. Adenomyosis can cause deep lesions and is persistent and refractory in nature due to its tumor-like biological characteristics, such as the ability to implant, adhere, and invade. The pathogenesis of adenomyosis is currently unclear. Therefore, new therapeutic approaches are urgently required. Exosomes are nanoscale vesicles secreted by cells that carry proteins, genetic materials and other biologically active components. Exosomes play an important role in maintaining tissue homeostasis and regulating immune responses and metabolism. A growing body of work has shown that exosomes and their contents are key to the development and progression of adenomyosis. This review discusses the current research progress, future prospects and challenges in this emerging therapeutic tool by providing an overview of the changes in the adenomyosis uterine microenvironment and the biogenesis and functions of exosomes, with particular emphasis on the role of exosomes and their contents in the regulation of cell migration, proliferation, fibrosis formation, neovascularization, and inflammatory responses in adenomyosis.

The role of CD8+ T cells in endometriosis: a systematic review

Background

Endometriosis is a chronic disease affecting 6-10% of women of reproductive age. It is an important cause of infertility and chronic pelvic pain with poorly understood aetiology. CD8+ T (CD8 T) cells were shown to be linked to infertility and chronic pain and play a significant role in lesion clearance in other pathologies, yet their function in endometriosis is unknown. We systematically evaluated the literature on the CD8 T in peripheral blood and endometriosis-associated tissues to determine the current understanding of their pathophysiological and clinical relevance in the disease and associated conditions (e.g. infertility and pelvic pain).

Methods

Four databases were searched (MEDLINE, EMBASE, Web of Science, CINAHL), from database inception until September 2022, for papers written in the English language with database-specific relevant terms/free-text terms from two categories: CD8 T cells and endometriosis. We included peer-reviewed papers investigating CD8 T cells in peripheral blood and endometriosis-associated tissues of patients with surgically confirmed endometriosis between menarche and menopause, and animal models with oestrous cycles. Studies enrolling participants with other gynaecological pathologies (except uterine fibroids and tubal factor infertility used as controls), cancer, immune diseases, or taking immune or hormonal therapy were excluded.

Results

28 published case-control studies and gene set analyses investigating CD8 T cells in endometriosis were included. Data consistently indicate that CD8 T cells are enriched in endometriotic lesions in comparison to eutopic endometrium, with no differences in peripheral blood CD8 T populations between patients and healthy controls. Evidence on CD8 T cells in peritoneal fluid and eutopic endometrium is conflicting. CD8 T cell cytotoxicity was increased in the menstrual effluent of patients, and genomic analyses have shown a clear trend of enriched CD8 T effector memory cells in the eutopic endometrium of patients.

Conclusion

Literature on CD8 T cells in endometriosis-associated tissues is inconsistent. Increased CD8 T levels are found in endometriotic lesions, however, their activation potential is understudied in all relevant tissues. Future research should focus on identifying clinically relevant phenotypes to support the development of non-invasive diagnostic and treatment strategies.

Systematic Review Registration

PROSPERO identifier CRD42021233304.

Pregnancy Outcomes of Assisted Reproductive Technology (ART) Cycle Complicated by Ovarian Hyperstimulation Syndrome (OHSS): Case Series Study

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a frequent, potentially lethal side effect of assisted reproductive technology (ART), distinguished by symptoms such as ovarian enlargement, ascites, and pleural effusion.

OBJECTIVE

This study is designed to study the effect of assisted reproductive technology (ART) cycle complicated by OHSS on pregnancy outcomes.

METHOD

A case series study at King Abdulaziz Medical City (KAMC) in Riyadh, Saudi Arabia, was executed to examine the pregnancy outcomes in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles. Fifteen patients were admitted to the IVF unit between January 2015 and December 2021. Data were retrieved from patients' medical records, and descriptive statistical methods were employed to analyze participants' data.

RESULTS

The study assessed pregnancy outcomes for 15 female participants (mean age=31.1 years, SD=3.46) with a BMI range of 20-40 (mean BMI=29.6, SD=6.4), of whom 33.3% were classified as obese. The primary factor of infertility was anovulation (66.7%), followed by male factors (20%). About 26.7% of those affected by OHSS had moderate OHSS, and 73.3% had severe OHSS, with 100% of those with severe OHSS having undergone three embryo transfers. None of the participants developed gestational diabetes mellitus (DM), but one participant had high blood sugar levels (6.67% of total participants), with a mean glucose of 6.3±2.0. There were no instances of preeclampsia, gestational hypertension, abnormal placentas, or congenital abnormalities in newborns among the participants. Preterm deliveries were common, with 33.3% delivering between 32 and 37 weeks, 6.7% before 28 weeks, and 33.3% within 28-32 weeks. Overall, 73.3% of the participants experienced pregnancy, and the birth mode was almost evenly split between vaginal and cesarean birth.

CONCLUSION

 In conclusion, this research provides an exploration into the outcomes of pregnancies in women undergoing assisted reproductive technology treatments complicated by ovarian hyperstimulation syndrome. It shows anovulation as a prevalent cause of infertility and a noteworthy incidence of severe OHSS. Despite these challenges, a significant number of women were able to experience pregnancy, although preterm deliveries and abortions were common. The delivery methods were fairly balanced between vaginal birth and cesarean section. These findings underscore the necessity for more effective strategies to manage OHSS and improve pregnancy outcomes in ART procedures.

Adenomyosis: single-cell transcriptomic analysis reveals a paracrine mesenchymal-epithelial interaction involving the WNT/SFRP pathway

OBJECTIVE

To assess the cellular and molecular landscape of adenomyosis.

DESIGN

Single-cell analysis of genome-wide messenger RNA (mRNA) expression (single-cell RNA sequencing) of matched tissues of endometrium, adenomyosis, and myometrium using relatively large numbers of viable cells.

SETTING

Not applicable.

PATIENT(S)

Patients (n = 3, age range 40-44 years) undergoing hysterectomy for diffuse adenomyosis.

MAIN OUTCOME MEASURE(S)

Definition of the molecular landscape of matched adenomyotic, endometrial and myometrial tissues from the same uterus using single-cell RNA sequencing and comparison of distinct cell types in these tissues to identify disease-specific cell populations, abnormal gene expression and pathway activation, and mesenchymal-epithelial interactions.

RESULT(S)

The largest cell population in the endometrium was composed of closely clustered fibroblast groups, which comprise 36% of all cells and seem to originate from pericyte progenitors differentiating to estrogen/progesterone receptor-expressing endometrial stromal- cells. In contrast, the entire fibroblast population in adenomyosis comprised a larger (50%) portion of all cells and was not linked to any pericyte progenitors. Adenomyotic fibroblasts eventually differentiate into extracellular matrix protein-expressing fibroblasts and smooth muscle cells. Hierarchical clustering of mRNA expression revealed a unique adenomyotic fibroblast population that clustered transcriptomically with endometrial fibroblasts, suggestive of an endometrial stromal cell population serving as progenitors of adenomyosis. Four other adenomyotic fibroblast clusters with disease-specific transcriptomes were distinct from those of endometrial or myometrial fibroblasts. The mRNA levels of the natural WNT inhibitors, named, secreted frizzled-related proteins 1, 2, and 4, were higher in these 4 adenomyotic fibroblast clusters than in endometrial fibroblast clusters. Moreover, we found that multiple WNTs, which originate from fibroblasts and target ciliated and unciliated epithelial cells and endothelial cells, constitute a critical paracrine signaling network in adenomyotic tissue. Compared with endometrial tissue, unciliated and ciliated epithelial cells in adenomyosis comprised a significantly smaller portion of this tissue and exhibited molecular evidence of progesterone resistance and diminished regulation of estrogen signaling.

CONCLUSION(S)

We found a high degree of heterogeneity in fibroblast-like cells in the adenomyotic uterus. The WNT signaling involving differential expression of secreted frizzled-related proteins, which act as decoy receptors for WNTs, in adenomyotic fibroblasts may have a key role in the pathophysiology of this disease.

Determination of soluble HLA-G serum levels in patients with adenomyosis and uterine fibroids before and after surgery

Adenomyosis is a benign gynaecological disease caused by the growth of endometrial tissue in the myometrium that affects approximately 30 % of child-bearing-age women. We evaluated the levels of soluble human leukocyte antigen G (sHLA-G) in the serum of patients with adenomyosis before and after treatment. Serum samples of 34 patients with adenomyosis and 31 patients with uterine fibroids were collected before and after the operation and were analysed for sHLA-G levels byELISAassay. The preoperative levels of serum sHLA-G in the adenomyosis group (28.05 ± 2.466 ng/ml) were significantly higher than those in the uterine fibroid group (18.53 ± 1.435 ng/ml) (P < 0.05). Serum sHLA-G levels in the adenomyosis group showed a decreasing trend at different time points after surgery (28.05 ± 14.38 ng/ml, 18.41 ± 8.34 ng/ml, and 14.45 ± 5.77 ng/ml). Adenomyosis patients who underwent total hysterectomy (n = 20) had a more significant decrease in sHLA-G levels in the early postoperative period (2 days post-operative) than those who underwent partial hysterectomy (n = 14). These results suggest that immunologic dysfunctions may be detected in patients with adenomyosis.

Molecular Targets for Nonhormonal Treatment Based on a Multistep Process of Adenomyosis Development

Adenomyosis is an estrogen-dependent gynecologic disease characterized by the presence of endometrial tissue within the myometrium. Adenomyosis presents with abnormal uterine bleeding, pelvic pains, and infertility. This review aimed to investigate the major estrogen downstream effectors involved in the process of adenomyosis development and their potential use for nonhormonal treatment. A literature search was performed for preclinical and clinical studies published between January 2010 and November 2021 in the PubMed and Google Scholar databases using a combination of specific terms. Adenomyosis presents with a wide spectrum of clinical manifestations from asymptomatic to severe through a complex process involving a series of molecular changes associated with inflammation, invasion, angiogenesis, and fibrosis. Adenomyosis may develop through a multistep process, including the acquisition of (epi)genetic mutations, tissue injury caused at the endometrial-myometrial interface, inside-to-outside invasion (from the endometrial side into the uterine wall), or outside-to-inside invasion (from the serosal side into the uterine wall), and epithelial-mesenchymal transition, tissue repair or remodeling in the myometrium. These processes can be regulated by increased estrogen biosynthesis and progesterone resistance. The expression of estrogen downstream effectors associated with persistent inflammation, fragile and more permeable vessel formation, and tissue injury and remodeling may be correlated with dysmenorrhea, heavy menstrual bleeding, and infertility, respectively. Key estrogen downstream targets (e.g., WNT/β-catenin, transforming growth factor-β, and nuclear factor-κB) may serve as hub genes. We reviewed the molecular mechanisms underlying the development of adenomyosis and summarized potential nonhormonal therapies.

Increased NKG2A+CD8+ T-cell exhaustion in patients with adenomyosis

Immune dysregulation has long been proposed to be associated with adenomyosis, but the underlying mediators and mechanisms remain largely unexplored. Here, we used flow cytometry to investigate the alterations in immune cell subsets in adenomyotic uteri and analyze the phenotype and function of abnormal immune cells. We found that an increase in cluster of differentiation (CD)8⁺ T-cell number was the predominant alteration in ectopic lesions in patients with adenomyosis and was significantly associated with the severity of adenomyosis. Importantly, we identified an exhausted natural killer group protein 2A (NKG2A)⁺CD8⁺ T-cell subset that was associated with the severity of adenomyosis and found that the number of these cells was significantly increased in the eutopic endometrium and ectopic lesions. In addition, the increases in the expression of NKG2A ligand histocompatibility leucocyte antigen E and interleukin-15 in glandular epithelial cells in the adenomyotic microenvironment might contribute to CD8⁺ T-cell exhaustion by promoting NKG2A expression on CD8⁺ T cells or inhibiting the effector function of these cells. In conclusion, our data revealed a previously unrecognized role for NKG2A⁺CD8⁺ T-cell exhaustion in the pathogenesis of adenomyosis, indicating that therapeutic interventions designed to target and reinvigorate exhausted CD8⁺ T cells may be beneficial for patients with adenomyosis.

Endometrial Inflammation and Impaired Spontaneous Decidualization: Insights into the Pathogenesis of Adenomyosis

Adenomyosis is an estrogen-dependent gynecologic disease characterized by the myometrial invasion of the endometrial tissue. This review summarized the current understanding and recent findings on the pathophysiology of adenomyosis, focusing on repeated menstruation, persistent inflammation, and impaired spontaneous decidualization. A literature search was performed in the PubMed and Google Scholar databases from inception to 30 April 2022. Thirty-one full-text articles met the eligibility criteria. Repeated episodes of physiological events (i.e., endometrial shedding, damage, proliferation, differentiation, repair, and regeneration) during the menstrual cycle are associated with inflammation, angiogenesis, and immune processes. The decidualization process in humans is driven by the rise in progesterone levels, independently of pregnancy (i.e., spontaneous decidualization). Adenomyotic cells produce angiogenic and fibrogenic factors with the downregulation of decidualization-associated molecules. This decidualization dysfunction and persistent inflammation are closely related to the pathogenesis of adenomyosis. Recently, it has been found that the reproductive tract microbiota composition and function in women with adenomyosis differ from those without. An increase in opportunistic pathogens and a decrease in beneficial commensals may promote impaired defense mechanisms against inflammation and predispose women to uncontrolled endometrial inflammation. However, currently, there is no direct evidence that adenomyosis is linked to pre-existing inflammation and impaired spontaneous decidualization. Overall, persistent inflammation, impaired spontaneous decidualization, and microbiota dysbiosis (i.e., an imbalance in the composition and function of endometrial microbiota) may be involved in the pathophysiology of adenomyosis.

The Role of Platelets in the Pathogenesis and Pathophysiology of Adenomyosis

Widely viewed as an enigmatic disease, adenomyosis is a common gynecological disease with bewildering pathogenesis and pathophysiology. One defining hallmark of adenomyotic lesions is cyclic bleeding as in eutopic endometrium, yet bleeding is a quintessential trademark of tissue injury, which is invariably followed by tissue repair. Consequently, adenomyotic lesions resemble wounds. Following each bleeding episode, adenomyotic lesions undergo tissue repair, and, as such, platelets are the first responder that heralds the subsequent tissue repair. This repeated tissue injury and repair (ReTIAR) would elicit several key molecular events crucial for lesional progression, eventually leading to lesional fibrosis. Platelets interact with adenomyotic cells and actively participate in these events, promoting the lesional progression and fibrogenesis. Lesional fibrosis may also be propagated into their neighboring endometrial-myometrial interface and then to eutopic endometrium, impairing endometrial repair and causing heavy menstrual bleeding. Moreover, lesional progression may result in hyperinnervation and an enlarged uterus. In this review, the role of platelets in the pathogenesis, progression, and pathophysiology is reviewed, along with the therapeutic implication. In addition, I shall demonstrate how the notion of ReTIAR provides a much needed framework to tether to and piece together many seemingly unrelated findings and how it helps to make useful predictions.

M2 macrophages enhance endometrial cell invasiveness by promoting collective cell migration in uterine adenomyosis

RESEARCH QUESTION

Are M2 macrophages implicated in endometrial invasiveness in adenomyosis?

DESIGN

Seventeen formalin-fixed paraffin-embedded uterine samples and 16 fresh endometrial biopsies were collected from women with or without adenomyosis. Double immunofluorescence was performed to determine the predominant macrophage population in adenomyosis between M1 and M2 phenotypes. The invasion capacity of endometrial cells was assessed by invasion assays and quantitative polymerase chain reaction for genes involved in cell motility and epithelial-mesenchymal transition (EMT). Specific mechanisms of invasion were investigated by immunohistochemistry for E-cadherin, N-cadherin and matrix metalloproteinase 9 (MMP9).

RESULTS

Only M2 macrophages were found to accumulate in adenomyosis, in higher numbers in both eutopic endometrium (P = 0.0109) and lesions (P = 0.0267) than healthy tissue. Co-culture with M2 macrophages significantly boosted invasion capacity in endometrial epithelial (P = 0.0002; P = 0.002) and stromal cells (P = 0.0469; P = 0.0047) from both adenomyosis patients and healthy controls. No gene expression differences indicating EMT were noted, either between co-cultured and control cells, or between healthy and adenomyotic cells. E- and N-cadherin protein expression did not differ significantly between endometrium from adenomyosis subjects and healthy tissue but MMP9 expression was increased in eutopic stroma from adenomyosis patients (P = 0.0492). In adenomyosis, both E-cadherin (P = 0.0379) and N-cadherin (P = 0.0196) were more extensively expressed in basal glands than functional glands.

CONCLUSIONS

M2 macrophages accumulate in adenomyosis and enhance invasion capacity of adenomyotic and even healthy endometrial cells, implying that macrophage infiltration alone may be sufficient to promote the disease. This study failed to detect any changes pointing to EMT, suggesting an alternative mode of invasion. Strong E- and N-cadherin-positive intercellular junctions in basal (invasive) glands suggest the involvement of collective cell migration in the invasion process of endometrium.

Bioinformatic analysis and machine learning to identify the diagnostic biomarkers and immune infiltration in adenomyosis

Background: Adenomyosis is a hormone-dependent benign gynecological disease characterized by the invasion of the endometrium into the myometrium. Women with adenomyosis can suffer from abnormal uterine bleeding, severe pelvic pain, and subfertility or infertility, which can interfere with their quality of life. However, effective diagnostic biomarkers for adenomyosis are currently lacking. The aim of this study is to explore the mechanism of adenomyosis by identifying biomarkers and potential therapeutic targets for adenomyosis and analyzing their correlation with immune infiltration in adenomyosis. Methods: Two datasets, GSE78851 and GSE68870, were downloaded and merged for differential expression analysis and functional enrichment analysis using R software. Weighted gene co-expression network analysis (WGCNA), the least absolute shrinkage and selection operator (LASSO), and support vector machine-recursive feature elimination (SVE-RFE) were combined to explore candidate genes. Quantitative reverse transcriptase PCR (qRT-PCR) was conducted to verify the biomarkers and receiver operating characteristic curve analysis was used to assess the diagnostic value of each biomarker. Single-sample Gene Set Enrichment Analysis (ssGSEA) and CIBERSORT were used to explore immune cell infiltration in adenomyosis and the correlation between diagnostic biomarkers and immune cells. Results: A total of 318 genes were differentially expressed. Through the analysis of differentially expressed genes and WGCNA, we obtained 189 adenomyosis-related genes. After utilizing the LASSO and SVM-RFE algorithms, four hub genes, namely, six-transmembrane epithelial antigen of the prostate-1 (STEAP1), translocase of outer mitochondrial membrane 20 (TOMM20), glycosyltransferase eight domain-containing 2 (GLT8D2), and NME/NM23 family member 5 (NME5) expressed in nucleoside-diphosphate kinase, were identified and verified by qRT-PCR. Immune infiltration analysis indicated that T helper 17 cells, CD56dim natural killer cells, monocytes, and memory B-cell may be associated with the occurrence of adenomyosis. There were significant correlations between the diagnostic biomarkers and immune cells. Conclusion: STEAP1, TOMM20, GLT8D2, and NME5 were identified as potential biomarkers and therapeutic targets for adenomyosis. Immune infiltration may contribute to the onset and progression of adenomyosis.

The Asian Society of Endometriosis and Adenomyosis guidelines for managing adenomyosis

This is the first guidelines for adenomyosis from the Asian Society of Endometriosis and Adenomyosis.

Intralipid infusion therapy as an adjunct treatment in women experiencing adenomyosis-related infertility

Background

Currently, there is some evidence that adenomyosis patients using gonadotropin-releasing hormone (GnRH) agonist long downregulation (LDR) prior to embryo transfer may improve in vitro fertilization (IVF) success rate, but not to the baseline expected success where there is no adenomyosis. Given the association between adenomyosis and an aberrant endometrial immune environment, many physicians also use prednisolone or Intralipid adjuvant treatments in combination with GnRH agonist therapy, despite neither being of proven benefit.

Objective

The purpose of this study was to investigate whether the addition of prednisolone or Intralipid immune therapy to GnRH agonist LDR improves fertility outcomes in patients with adenomyosis.

Methods

This is a retrospective cohort study of 116 consecutive adenomyosis patients who underwent their first transfer of a genetically screened euploid embryo between January 2019 and December 2020 at a private IVF clinic.

Results

There was no difference in maternal age, body mass index, number of embryo's transferred and gravidity or parity among the three treatment groups. Patients who received Intralipid had a poorer prognosis with a longer duration of infertility (4 years) and a higher number of previous embryo transfers (ETs, 5 previous ETs) compared to the comparison groups. Logistic regression analysis adjustment for all covariates revealed that LDR plus Intralipid therapy produced significantly higher live birth rates (LBRs; 60%) compared to LDR alone (40% LBR); yet, the addition of prednisolone to GnRH agonist LDR (30% LBR) provided no additional live birth benefit.

Conclusion

In this retrospective analysis, we showed Intralipid adjuvant treatment in combination with GnRH agonist therapy in adenomyosis patients undergoing IVF resulted in a LBR expected in women without adenomyosis using preimplantation genetic testing screened embryos. This benefit was not seen when using prednisolone as an adjuvant to GnRH agonist LDR. Future randomized clinical trials will be required to confirm the therapeutic benefit of Intralipid in combination with GnRH agonist therapy.

How do pre-pregnancy endometrial macrophages contribute to pregnancy?

Macrophages are professional phagocytes with a wide distribution in all tissues throughout the body. Macrophages play a crucial role in homeostasis and numerous physiological processes beyond innate and adaptive immunity, including cellular debris removal, metabolic regulation, tissue repair, and tissue remodeling. Uterine macrophages are a heterogeneous and highly plastic subset of immune cells regulated by the local microenvironment and, in addition to their anti-inflammatory and anti-infective functions, support the establishment and maintenance of pregnancy. Comprehensive reviews have summarized the role of decidual macrophages during pregnancy. However, the distribution of macrophages in the endometrium prior to pregnancy, their functional remodeling, and the knock-on effects on subsequent pregnancies have not been elucidated. In this review, we focus on 1) how the phenotypes of endometrial macrophages and their interactions with other endometrial cells indicate or contribute to the subsequent pregnancy, 2) the adaptive switching of endometrial macrophages during the initial establishment of pregnancy, 3) and the pregnancy complications and pregnancy-related disorders associated with endometrial macrophages.

Pathophysiology, diagnosis, and management of endometriosis

Endometriosis affects approximately 190 million women and people assigned female at birth worldwide. It is a chronic, inflammatory, gynecologic disease marked by the presence of endometrial-like tissue outside the uterus, which in many patients is associated with debilitating painful symptoms. Patients with endometriosis are also at greater risk of infertility, emergence of fatigue, multisite pain, and other comorbidities. Thus, endometriosis is best understood as a condition with variable presentation and effects at multiple life stages. A long diagnostic delay after symptom onset is common, and persistence and recurrence of symptoms despite treatment is common. This review discusses the potential genetic, hormonal, and immunologic factors that lead to endometriosis, with a focus on current diagnostic and management strategies for gynecologists, general practitioners, and clinicians specializing in conditions for which patients with endometriosis are at higher risk. It examines evidence supporting the different surgical, pharmacologic, and non-pharmacologic approaches to treating patients with endometriosis and presents an easy to adopt step-by-step management strategy. As endometriosis is a multisystem disease, patients with the condition should ideally be offered a personalized, multimodal, interdisciplinary treatment approach. A priority for future discovery is determining clinically informative sub-classifications of endometriosis that predict prognosis and enhance treatment prioritization.

Altered Expression of Interleukin-18 System mRNA at the Level of Endometrial Myometrial Interface in Women with Adenomyosis

Adenomyosis is a uterine pathology characterized by a deep invasion of endometrial glands and stroma, disrupting the endometrial−myometrial interface (EMI). Interleukin-18 (IL-18) system is a dominant cytokine involved in the menstrual cycle of human endometrium. IL-18 may play a defensive role against maternal immune response in the uterine cavity. The present study was designed to determine IL-18-mediated immune response at the level of EMI. We uncovered that mRNA of IL-18 system, including IL-18, IL-18 receptor (IL-18R), and its antagonist, IL-18 binding protein (IL-18BP), expressed in eutopic, ectopic endometrium, and corresponding myometrium in patients with adenomyosis. IL-18 system was demonstrated in paired tissue samples by immunochemistry and immunofluorescence study. According to RT-PCR with CT value quantification and 2−∆∆Ct method, a significant down-regulation of IL-18BP in corresponding myometrium in comparison to eutopic endometrium (p < 0.05) indicates that the IL-18 system acts as a local immune modulator at the level of EMI and regulating cytokine networks in the pathogenesis of adenomyosis. Furthermore, an increased IL-18 antagonist to agonist ratio was noted in ectopic endometrium compared with corresponding myometrium. We suggest that altered IL-18 system expression contributes to immunological dysfunction and junctional zone disturbance in women with adenomyosis.

Uterine disorders and iron deficiency anemia

Abnormal uterine bleeding (AUB) is a clinical entity which can lead to iron deficiency anemia. Classification according to the acronym PALM-COEIN (polyp, adenomyosis, leiomyoma, malignancy, and hyperplasia; coagulopathy, ovulatory dysfunction, endometrial, iatrogenic, and not otherwise classified) provides a structured approach to establish the cause of AUB. The goal of this review is to discuss the different mechanisms and the relationship between uterine disorders and AUB. Heavy menstrual bleeding, a subgroup of AUB, is more closely related to the presence of uterine fibroids. The relationship between heavy menstrual bleeding and uterine fibroids remains poorly characterized, particularly the understanding of endometrial function in women with structural myometrial features such as leiomyomas. A number of theories have been proposed in the literature and are discussed in this review. Uterine adenomyosis is also a frequent cause of AUB, and its pathogenesis is still far from being fully elucidated. The mechanisms contributing to its development are multifactorial. Many theories lean toward invasion of the myometrium by endometrial cells. Both clinical and basic studies favor the theory of direct invasion, although de novo development of adenomyosis from Müllerian rests or stem cells has not been ruled out. Development of adenomyotic lesions involves repeated tissue injury and repair. In addition, this review describes the other causes of AUB such as endometrial polyps, cesarean scar defects, and uterine vascular abnormalities. Endometrial polyps are often asymptomatic, but approximately 68% of women have concomitant AUB. Histologic alterations in the lower uterine segment in patients who had undergone cesarean sections were identified and may explain the cause of AUB.

The Prevalence and Clinical Impact of Adenomyosis in Pregnancy-Related Hysterectomy

Background: The epidemiology of adenomyosis has been traditionally based on patients undergoing hysterectomy for gynecological indications, while its prevalence among hysterectomies performed for obstetric complications is unknown. The aim of this study was to assess the prevalence and clinical impact of adenomyosis diagnosed through histology among women undergoing pregnancy-related hysterectomy (PH). Methods: This was a retrospective cohort study. Women who delivered at a tertiary care regional obstetric hub in Milan between 2009 and 2020 were reviewed to identify cases of PH. Histopathological reports of surgical specimens were examined. Cases with adenomyosis were compared to those without adenomyosis for baseline characteristics, obstetric history and outcomes. Results: During the study period there were 71,061 births and a total of 130 PH, giving a PH incidence of 1.83 per 1000 deliveries. Adenomyosis cases were 18, giving a prevalence of 13.8%. Adenomyosis was associated with placenta previa (77.8 vs. 45.5%, p = 0.01), chorionamnionitis (27.8 vs. 5.4%, p = 0.008), lower gestational age at birth (32 ± 4.6 vs. 35.5 ± 3.6 weeks’ gestation, p = 0.0004), and intrauterine fetal demise among twin pregnancies (50 vs. 4.5%, p = 0.048). Conclusion: Adenomyosis entails a relevant impact on obstetric and perinatal outcomes related to PH. More evidence is needed on the clinical relevance of an ultrasonographic diagnosis of adenomyosis before conception.

Excess Heme Promotes the Migration and Infiltration of Macrophages in Endometrial Hyperplasia Complicated with Abnormal Uterine Bleeding

In patients, endometrial hyperplasia (EH) is often accompanied by abnormal uterine bleeding (AUB), which is prone to release large amounts of heme. However, the role of excess heme in the migration and infiltration of immune cells in EH complicated by AUB remains unknown. In this study, 45 patients with AUB were divided into three groups: a proliferative phase group (n = 15), a secretory phase group (n = 15) and EH (n = 15). We observed that immune cell subpopulations were significantly different among the three groups, as demonstrated by flow cytometry analysis. Of note, there was a higher infiltration of total immune cells and macrophages in the endometrium of patients with EH. Heme up-regulated the expression of heme oxygenase-1 (HO-1) and nuclear factor erythroid-2-related factor 2 (Nrf2) in endometrial epithelial cells (EECs) in vitro, as well as chemokine (e.g., CCL2, CCL3, CCL5, CXCL8) levels. Additionally, stimulation with heme led to the increased recruitment of THP-1 cells in an indirect EEC-THP-1 co-culture unit. These data suggest that sustained and excessive heme in patients with AUB may recruit macrophages by increasing the levels of several chemokines, contributing to the accumulation and infiltration of macrophages in the endometrium of EH patients, and the key molecules of heme metabolism, HO-1 and Nrf2, are also involved in this regulatory process.

Personalized Nutrition in the Management of Female Infertility: New Insights on Chronic Low-Grade Inflammation

Increasing evidence on the significance of nutrition in reproduction is emerging from both animal and human studies, suggesting a mutual association between nutrition and female fertility. Different “fertile” dietary patterns have been studied; however, in humans, conflicting results or weak correlations are often reported, probably because of the individual variations in genome, proteome, metabolome, and microbiome and the extent of exposure to different environmental conditions. In this scenario, “precision nutrition”, namely personalized dietary patterns based on deep phenotyping and on metabolomics, microbiome, and nutrigenetics of each case, might be more efficient for infertile patients than applying a generic nutritional approach. In this review, we report on new insights into the nutritional management of infertile patients, discussing the main nutrigenetic, nutrigenomic, and microbiomic aspects that should be investigated to achieve effective personalized nutritional interventions. Specifically, we will focus on the management of low-grade chronic inflammation, which is associated with several infertility-related diseases.

Endometrial macrophages in health and disease

Macrophages are present in the endometrium throughout the menstrual cycle and are most abundant during menstruation. Endometrial macrophages contribute to tissue remodeling during establishment of pregnancy and are thought to play key roles in mediating tissue breakdown and repair during menstruation. Despite these important roles, the phenotype and function of endometrial macrophages remains poorly understood. In this review, we summarize approaches used to characterize endometrial macrophage phenotype, current understanding of the functional role of macrophages in normal endometrial physiology as well as the putative contribution of macrophage dysfunction to women's reproductive health disorders.

Mechanisms and Pathogenesis of Adenomyosis

Purpose of the Review

The purpose of this review is to provide a synopsis of all the mechanisms involved in the pathogenesis of adenomyosis. It will summarize recent advances in the field, discussing current controversies, and considering potential future directions.

Recent Findings

Adenomyosis pathogenesis is still a topic under investigation, however advancements in the understanding of disease development and mechanisms have been made. New data coming from new next generation sequencing-based studies and more-in-depth acquisitions on sex hormones imbalance, neuroangiogenesis, inflammation, fibrosis and cell proliferation have been obtained.

Summary

Adenomyosis is a uterine disorder that affects women of reproductive age, characterized by a benign invasion of the endometrium basalis (glands and stroma) within the myometrium.

So far, three theories for the pathophysiology of adenomyosis have been proposed:

In order to invade and develop, endometrial cells require a series of pathogenetic mechanisms which drive to adenomyosis. Altered sex steroids hormones receptors may be the primary event which causes increased endometrial cell proliferations and differentiation from epithelial to mesenchymal cells. Once invaded the myometrium, an inflammatory reaction is displayed, probably driven by local immune changes. The processes of neuroangiogenesis and fibrosis are also involved in the adenomyosis development and may explain some of the associated clinical symptoms (dysmenorrhea, abnormal uterine bleeding, and infertility).

Classifications of Adenomyosis and Correlation of Phenotypes in Imaging and Histopathology to Clinical Outcomes: a Review

Purpose of Review

To provide an update on published classification and reporting systems for adenomyosis. There is an urgent need to standardize reporting of various phenotypes of adenomyosis into a validated and globally recognized system. This can be used to examine the nature and severity of adenomyosis symptoms and inform the design, evaluation, and implementation of appropriate treatment options.

Recent Findings

In recent years, several new proposals for adenomyosis classification have emerged. Most are MRI-based and include features such as uterine size, junctional zone thickness, size and location of the lesions, and distribution patterns. To date, none of those proposals has been validated. Only one recent classification based on transvaginal ultrasound was validated for interobserver congruence and correlated to clinical findings. However, the differentiation of diffuse and focal adenomyosis still lacks consensus. In addition, only a few authors advocated imaging-based definitions.

Summary

There is a need for one or a combination of a classification and reporting system for adenomyosis. To date, there is no widely accepted and validated system.

Menstruation-Related Disorders—Dysmenorrhea and Heavy Bleeding—as Significant Epiphenomena in Women With Rheumatic Diseases

Background: In women with rheumatic diseases (RDs) menstruation-related disorders have never been investigated. The aim of this study was to evaluate gynecological symptoms/disorders in fertile age women with RDs.

Materials and methods: All patients (n = 200) filled up a self-administered questionnaire on their gynecological history, menstrual cycle pattern, menstrual-related symptoms, and quality of life (QoL). The RD group was then compared to a control group of 305 age-matched fertile age women.

Results: Among patients with RDs, 58% had arthritis, 40% connective tissue diseases (CTDs), and 1.5% systemic vasculitis. No differences were observed between CTDs and arthritis, except for a family history of HMB which was more common among women with CTDs (p < .01). When compared to controls, women with RDs reported more frequent heavy menstrual bleeding (HMB) during adolescence (51.7 and 25.4%, respectively; p = .0001) and adult life (37.7 and 25.9%, respectively; p = .0065). Also, dysmenorrhea in adolescence was significantly more common among cases (55.6 and 45.4%, respectively; p = .0338). Gynecological pain (dysmenorrhea, non-menstrual pelvic pain, dyspareunia, dysuria, and dyschezia) in patients with RDs was more frequent than in controls (p = .0001, .0001, .0001, .0001, .0002, respectively). Considering women who reported moderate and severe symptoms in RDs, dysmenorrhea and dyspareunia remain significantly more frequent in women with RDs than in controls (p = .0001; p = .0022; respectively). QoL scores were significantly reduced in women with RDs, either in physical (p = .0001) and mental domains (p = .0014) of short-form 12.

Conclusion: Women affected by RDs frequently presented menstruation-related disorders; thus, female patients with RDs should be questioned about gynecological symptoms and referred to the gynecologist for an accurate evaluation.

Establishment of Adenomyosis Organoids as a Preclinical Model to Study Infertility

Adenomyosis is related to infertility and miscarriages, but so far there are no robust in vitro models that reproduce its pathological features to study the molecular mechanisms involved in this disease. Endometrial organoids are in vitro 3D models that recapitulate the native microenvironment and reproduce tissue characteristics that would allow the study of adenomyosis pathogenesis and related infertility disorders. In our study, human endometrial biopsies from adenomyosis (n = 6) and healthy women (n = 6) were recruited. Organoids were established and hormonally differentiated to recapitulate midsecretory and gestational endometrial phases. Physiological and pathological characteristics were evaluated by immunohistochemistry, immunofluorescence, qRT-PCR, and ELISA. Secretory and gestational organoids recapitulated in vivo glandular epithelial phenotype (pan-cytokeratin, Muc-1, PAS, Laminin, and Ki67) and secretory and gestational features (α-tubulin, SOX9, SPP1, PAEP, LIF, and 17βHSD2 expression and SPP1 secretion). Adenomyosis organoids showed higher expression of TGF-β2 and SMAD3 and increased gene expression of SPP1, PAEP, LIF, and 17βHSD2 compared with control organoids. Our results demonstrate that organoids derived from endometria of adenomyosis patients and differentiated to secretory and gestational phases recapitulate native endometrial-tissue-specific features and disease-specific traits. Adenomyosis-derived organoids are a promising in vitro preclinical model to study impaired implantation and pregnancy disorders in adenomyosis and enable personalized drug screening.

Transcriptome analysis of eutopic endometrium in adenomyosis after GnRH agonist treatment

BACKGROUND

Adenomyosis is a chronic gynecological disease characterized by invasion of the uterine endometrium into the muscle layer. In assisted reproductive technology (ART), gonadotropin-releasing hormone agonist (GnRHa) is often used to improve pregnancy rates in patients with adenomyosis, but the underlying mechanisms are poorly understood.

METHODS

Eutopic endometrial specimens were collected from patients with adenomyosis before and after GnRHa treatment in the midsecretory phase. RNA sequencing (RNA-Seq) of these specimens was performed for transcriptome analysis. The differentially expressed genes (DEGs) of interest were confirmed by real-time PCR and immunohistochemistry.

RESULTS

A total of 132 DEGs were identified in the endometrium of patients with adenomyosis after GnRHa treatment compared with the control group. Bioinformatics analysis predicted that immune system-associated signal transduction changed significantly after GnRHa treatment. Chemokine (C-C motif) ligand 21 (CCL21) was found to be highly expressed in the eutopic endometrium after GnRHa treatment, which may be involved in the improvement of endometrial receptivity in adenomyosis.

CONCLUSION

This study suggests that molecular regulation related to immune system-associated signal transduction is an important mechanism of GnRHa treatment in adenomyosis. Immunoreactive CCL21 is thought to regulate inflammatory events and participate in endometrial receptivity in adenomyosis.