Multi-Lineage Human Endometrial Organoids on Acellular Amniotic Membrane for Endometrium Regeneration

Development of regenerative therapies targeting fibrotic endometrium in intrauterine adhesion or thin endometrium to restore uterine function

Intrauterine adhesions (IUA) and thin endometrium (TE) represent significant challenges in human reproduction. The condition arises frequently from damage to the endometrial basal layer, leading to fibrous tissue replacing the functional endometrium and impairing the uterus's ability to accept embryo implantation. Conventional treatments, mainly including hysteroscopic adhesiolysis and estrogen therapies, have shown limited success, particularly in severe cases. Regenerative medicine, with its focus on stem cell-based therapies and biomaterials, offers a promising avenue for restoring endometrial function and structure. This review synthesizes the current landscape of endometrial regeneration, focusing on the therapeutic potential of stem cells, the supportive role of biomaterials, and the importance of understanding molecular mechanisms to develop effective strategies for reconstruction of endometrial functional and fertility restoration.

Application of adult stem cells in obstetrics and gynecology: A scoping review

Background

Advancements in regenerative medicine have led to the applicability of stem cell technology in various diseases. Stem cells that have self-renewable abilities may differentiate into several cell types to provide therapeutic potential. Among different stem cells, adult stem cells are considered as the safest with remarkable potential for therapeutic application. In this review, we provide current available evidence regarding the application of adult stem cells in medicine, especially in the field of obstetrics and gynecology.

Objective

This scoping review aims to map and describe the current research on adult stem cell application in obstetrics and gynecology.

Methods

We performed a systematic search on PubMed, Google Scholar, and Cochrane Library in August 2024 to identify research articles involving adult stem cells in the field of obstetrics and gynecology. We used the Deduplicate website to filter articles based on keywords that met our inclusion and exclusion criteria. The results were presented based on recommendations from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews.

Results

We found 42 articles that met the inclusion criteria. Some studies were clinical studies, whereas the majority were preclinical studies. We categorized the articles into clinical and preclinical studies to understand their applicability in human subjects.

Conclusions

Adult stem cell therapy is a candidate treatment for several pathologies in obstetrics and gynecology. The promising results of adult stem cell therapy, especially in degenerative gynecologic diseases, may lead to further application of the technology in the near future.

Steps towards the clinical application of endometrial and menstrual fluid mesenchymal stem cells for the treatment of gynecological disorders

INTRODUCTION

The human endometrium is a highly regenerative tissue that contains mesenchymal stem/stromal cells (MSCs). These MSCs are sourced via office-based biopsies and menstrual fluid, providing a less invasive and readily available option for cell-based therapies. This review provides an update on endometrial-derived MSCs as a treatment option for gynecological diseases.

AREAS COVERED

This narrative review covers the characterization and therapeutic mechanisms of endometrium biopsy-derived MSCs (eMSCs) and menstrual fluid-derived mesenchymal stromal cells (MenSCs), highlighting similarities and differences. It also covers studies of their application in preclinical animal models and in clinical trials as potential cell-based therapies for gynecological diseases.

EXPERT OPINION

eMSCs and MenSCs from a homologous tissue source have the potential to promote regenerative activity as a treatment for gynecological diseases. Both eMSCs and MenSCs demonstrate therapeutic benefits through their paracrine activity in tissue regeneration, immunomodulation, angiogenesis, and mitigating fibrosis. Further research is essential to establish standardized isolation and characterization protocols, particularly for heterogeneous MenSCs, and to fully understand their mechanisms of action. Implementing SUSD2 magnetic bead sorting for purifying eMSCs from endometrial tissues and menstrual fluid is crucial for their use in future cell-based therapies. Optimization of production, storage, and delivery methods will maximize their therapeutic effectiveness.

SCGB1D4 downregulation links to fibrosis in intrauterine adhesion patients and rat models†

Intrauterine adhesions (IUA) represent a prevalent uterine endometrial disorder frequently correlated with menstrual irregularities and infertility. Some members of the secretoglobin(SCGB) family have demonstrated anti-fibrotic effects, however, the specific role of SCGB1D4, one of the family members, in anti-fibrosis remains unclear. This study aimed to investigate the expression of SCGB1D4 in IUA tissues, validate the role of SCGB1D4 in endometrial fibrosis, and assess its potential therapeutic significance by analyzing clinical features and constructing rat and cell models. Clinical characteristics of patients with intrauterine adhesions (IUA) were compared and analyzed against control subjects. Additionally, a rat uterine adhesion model was successfully established using a combination of mechanical injury and infection. The expression levels of SCGB1D4 in patient tissues and animal models were detected through immunohistochemistry, Western blot, and real-time fluorescence quantitative PCR, and the changes in fibrosis markers COL1A1 and α-SMA were also evaluated. Furthermore, human endometrial stromal cell lines (HESCs) induced by transforming growth factor-β-1 conversion were differentiated into myofibroblasts to establish cell models of intrauterine adhesion. We detected the expression of SCGB1D4 and fibrosis-related factors by real-time fluorescence quantitative PCR and Western blot. Cell proliferation and cell cycle changes were assessed using flow cytometry and CCK8. IUA patients showed increased miscarriage rates and decreased endometrial thickness. Clinical tissue specimens revealed significantly lower expression of SCGB1D4 in the endometrial tissues of IUA patients, accompanied by a notable increase in COL1A1 and α-SMA. The established rat model of intrauterine adhesion exhibited decreased expression of SCGB1D4 and a significant increase in fibrosis. After overexpression of SCGB1D4 on the IUA cell model, SCGB1D4 expression was elevated, while COL1A1 and α-SMA expression was significantly reduced. Cell proliferation was inhibited and cell cycle distribution was altered. This study has confirmed the low expression of SCGB1D4 in patients with IUA, as well as in animal and cell models. Furthermore, the overexpression of SCGB1D4 in a cell model of IUA demonstrates that it may play a key role in inhibiting fibrosis. SCGB1D4 holds promise as a potential therapeutic target for IUA, providing a new avenue for overcoming fertility issues caused by IUA.

Organoid development and applications in gynecological cancers: the new stage of tumor treatment

Gynecologic cancers (GCs), including cervical cancer (CC), ovarian cancer (OC), endometrial cancer (EC), as well as vulvar and vaginal cancers, represent major health threats to women, with increasing incidence rates observed globally. Conventional treatments, such as surgery, radiation therapy, and chemotherapy, are often hindered by challenges such as drug resistance and recurrence, contributing to high mortality rates. Organoid technology has emerged as a transformative tool in cancer research, offering in vitro models that closely replicate the tumor cell architecture and heterogeneity of primary cancers. Tumor-derived organoids preserve the histological and molecular characteristics of the original tumors, making them invaluable for studying tumor biology, molecular pathways, and the tumor immune microenvironment. Furthermore, organoids play a crucial role in biomarker discovery, drug screening, and the development of personalized therapeutic strategies. In contrast to traditional cell lines and patient-derived xenograft (PDX) models, gynecologic cancer organoids accurately mirror the genetic mutations and specific gene expression profiles of primary tumors. This review provides an overview of recent advancements in the development of gynecologic cancer organoid models, highlighting their contributions to understanding disease mechanisms, facilitating drug discovery, and advancing precision medicine. It also addresses the potential and challenges of organoid technology, with a focus on its role in advancing personalized treatment approaches for GCs.

Engraftment of self-renewing endometrial epithelial organoids promotes endometrial regeneration by differentiating into functional glands in rats

Introduction

Extensive trauma frequently disrupts endometrial regeneration by diminishing endometrial stem cells/progenitor cells, affecting female fertility. While bone marrow mesenchymal stem cell (BMSC) transplantation has been suggested as an approach to address endometrial injury, it comes with certain limitations. Recent advancements in endometrial epithelial organoids (EEOs) have displayed encouraging potential for endometrial regeneration. Therefore, this study aims to explore whether EEOs surpass BMSCs in their ability to repair injured endometrium and to examine whether the restoration process involves the integration of EEOs into the endometrial tissue of the recipient.

Methods

We developed rat EEOs (rEEOs) mimicking the features of the rat endometrium. Subsequently, we created a rat model of endometrial injury to compare the effects of rEEOs and rat BMSCs (rBMSCs) on endometrial regeneration and reproductive recovery. Bulk RNA-sequencing analysis was conducted to further investigate the capacity of rEEOs for endometrial regeneration and to identify discrepancies between rEEOs and rBMSCs. Additionally, to track the fate of the transplanted cells in vivo, we transplanted green fluorescent protein (GFP) -labelled rEEOs or red fluorescent protein (RFP) -labelled rBMSCs.

Results

In a rat model of endometrial injury, we observed that fertility recovery in rats transplanted with rEEOs was more comparable to that of normal rats than in those treated with rBMSC. rEEOs possess a high concentration of endometrial epithelial stem/progenitor cells and secrete vascular endothelial growth factor (VEGF)-A to promote endometrial neovascularization. Significantly, we observed that cells from GFP-labelled rEEOs could integrate and differentiate into functional glands within the injured endometrium of recipient rats.

Discussion

EEOs offer a transformative approach to address the challenges of endometrial trauma. Their remarkable regenerative potential holds promise for the restoration of damaged endometrium. As we venture into the future, the concept of utilizing patient-specific EEOs for transplantation emerges as a tantalizing prospect. However, the EEOs in our experiments were mainly cultured in Matrigel, which has barriers to clinical translation as a biomaterial, a new biomaterial to be explored. Secondly, our experiments have been successful only in rat models, and more efforts need to be made before clinical translation.

Current advances in understanding endometrial epithelial cell biology and therapeutic applications for intrauterine adhesion

The human endometrium is a highly regenerative tissue capable of undergoing scarless repair during the menstruation and postpartum phases. This process is mediated by endometrial adult stem/progenitor cells. During the healing of endometrial injuries, swift reepithelization results in the rapid covering of the wound surface and facilitates subsequent endometrial restoration. The involvement of endogenous endometrial epithelial stem cells, stromal cells, and bone marrow-derived cells in the regeneration of the endometrial epithelium has been a subject of prolonged debate. Increasing evidence suggests that the regeneration of the endometrial epithelium mainly relies on epithelial stem cells rather than stromal cells and bone marrow-derived cells. Currently, no consensus has been established on the identity of epithelial stem cells in the epithelial compartment. Several markers, including stage-specific embryonic antigen-1 (SSEA-1), sex-determining region Y-box 9 (SOX9), neural-cadherin (N-cadherin), leucine-rich-repeat-containing G-protein-coupled receptor 5 (LGR5), CD44, axis inhibition protein 2 (Axin2), and aldehyde dehydrogenase 1A1 (ALDH1A1), have been suggested as potential candidate markers for endometrial epithelial stem cells. The identification of endometrial epithelial stem cells contributes to our understanding of endometrial regeneration and offers new therapeutic insights into diseases characterized by regenerative defects in the endometrium, such as intrauterine adhesion. This review explores different perspectives on the origins of human and mouse endometrial epithelial cells. It summarizes the potential markers, locations, and hierarchies of epithelial stem cells in both human and mouse endometrium. It also discusses epithelial cell-based treatments for intrauterine adhesion, hoping to inspire further research and clinical application of endometrial epithelial stem cells.

Bioengineering approaches for the endometrial research and application

The endometrium undergoes a series of precise monthly changes under the regulation of dynamic levels of ovarian hormones that are characterized by repeated shedding and subsequent regeneration without scarring. This provides the potential for wound healing during endometrial injuries. Bioengineering materials highlight the faithful replication of constitutive cells and the extracellular matrix that simulates the physical and biomechanical properties of the endometrium to a larger extent. Significant progress has been made in this field, and functional endometrial tissue bioengineering allows an in-depth investigation of regulatory factors for endometrial and myometrial defects in vitro and provides highly therapeutic methods to alleviate obstetric and gynecological complications. However, much remains to be learned about the latest progress in the application of bioengineering technologies to the human endometrium. Here, we summarize the existing developments in biomaterials and bioengineering models for endometrial regeneration and improving the female reproductive potential.

Intrauterine adhesion

Intrauterine adhesions (IUA) occurred in the reproductive-age women are a big economic and health problem, resulting in severe impairment of social, psychological and physical function of the female genital organs. IUA-related symptoms or signs are varied greatly from free of symptoms or ambiguous symptoms (an incidental finding during the intervention) to ceased menstruation and loss of fecundability. The underlying pathophysiology is not completely understood, but intrauterine damage with broken basal layers of the endometrium formatting scar tissues or fibrosis in the endometrium with subsequently causing partial or complete occlusion of the uterine cavity may be a well-accepted hypothesis. Previously, infection is the most common cause to develop IUA, but now, intrauterine surgery may be a critical cause contributing to the majority of cases of IUA. In the current review, update information about the etiology, epidemiology, pathophysiology, sequelae and prevention of IUA will be renewed. We emphasize the importance of awareness of IUA, and primary prevention should be considered in the routine clinical practice if intrauterine surgery has been applied, based on uncertainty of ideal treatment for the established IUA and unpredictable outcomes after IUA treatment. So far, evidence supports that hyaluronic acid with/without other strategy is the most valuable and effective method to reduce the formation and re-formation of IUA as well as to achieve the best fertility outcome.

Prospects for the Application of Transplantation With Human Amniotic Membrane Epithelial Stem Cells in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a multi-organ and systemic autoimmune disease characterized by an imbalance of humoral and cellular immunity. The efficacy and side effects of traditional glucocorticoid and immunosuppressant therapy remain controversial. Recent studies have revealed abnormalities in mesenchymal stem cells (MSCs) in SLE, leading to the application of bone marrow-derived MSCs (BM-MSCs) transplantation technique for SLE treatment. However, autologous transplantation using BM-MSCs from SLE patients has shown suboptimal efficacy due to their dysfunction, while allogeneic mesenchymal stem cell transplantation (MSCT) still faces challenges, such as donor degeneration, genetic instability, and immune rejection. Therefore, exploring new sources of stem cells is crucial for overcoming these limitations in clinical applications. Human amniotic epithelial stem cells (hAESCs), derived from the eighth-day blastocyst, possess strong characteristics including good differentiation potential, immune tolerance with low antigen-presenting ability, and unique immune properties. Hence, hAESCs hold great promise for the treatment of not only SLE but also other autoimmune diseases.

Applications of Engineered Skin Tissue for Cosmetic Component and Toxicology Detection

The scale of the cosmetic market is increasing every day. There are many safety risks to cosmetics, but they benefit people at the same time. The skin can become red, swollen, itchy, chronically toxic, and senescent due to the misuse of cosmetics, triggering skin injuries, with contact dermatitis being the most common. Therefore, there is an urgent need for a system that can scientifically and rationally detect the composition and perform a toxicological assessment of cosmetic products. Traditional detection methods rely on instrumentation and method selection, which are less sensitive and more complex to perform. Engineered skin tissue has emerged with the advent of tissue engineering technology as an emerging bioengineering technology. The ideal engineered skin tissue is the basis for building good in vitro structures and physiological functions in this field. This review introduces the existing cosmetic testing and toxicological evaluation methods, the current development status, and the types and characteristics of engineered skin tissue. The application of engineered skin tissue in the field of cosmetic composition detection and toxicological evaluation, as well as the different types of tissue engineering scaffold materials and three-dimensional (3D) organoid preparation approaches, is highlighted in this review to provide methods and ideas for constructing the next engineered skin tissue for cosmetic raw material component analysis and toxicological evaluation.