Interleukin 6 at menstruation promotes the proliferation and self-renewal of endometrial mesenchymal stromal/stem cells through the WNT/β-catenin signaling pathway.

Background: At menstruation, the functional layer of the human endometrium sheds off due to the trigger of the release of inflammatory factors, including interleukin 6 (IL-6), as a result of a sharp decline in progesterone levels, leading to tissue breakdown and bleeding. The endometrial mesenchymal stem-like cells (CD140bCD146 eMSC) located in the basalis are responsible for the cyclical regeneration of the endometrium after menstruation. Endometrial cells from the menstruation phase have been proven to secrete a higher amount of IL-6 and further enhance the self-renewal and clonogenic activity of eMSC.

Endometrial mesenchymal stromal/stem cells improve regeneration of injured endometrium in mice.

Background: The monthly regeneration of human endometrial tissue is maintained by the presence of human endometrial mesenchymal stromal/stem cells (eMSC), a cell population co-expressing the perivascular markers CD140b and CD146. Endometrial regeneration is impaired in the presence of intrauterine adhesions, leading to infertility, recurrent pregnancy loss and placental abnormalities. Several types of somatic stem cells have been used to repair the damaged endometrium in animal models, reporting successful pregnancy.

A construct of adipose-derived mesenchymal stem cells-laden collagen scaffold for fertility restoration by inhibiting fibrosis in a rat model of endometrial injury.

Severe endometrium damage causes pathological conditions such as thin endometrium and intrauterine adhesion, resulting in uterine factor infertility. Mesenchymal stem cell (MSC) therapy is a promising strategy in endometrial repair; yet, exogenous MSCs still raise concerns for safety and ethical issues. Human adipose-derived mesenchymal stem cells (ADMSCs) residing in adipose tissue have high translational potentials due to their autologous origin.

Resolving the gene expression maps of human first-trimester chorionic villi with spatial transcriptome.

The placenta is important for fetal development in mammals, and spatial transcriptomic profiling of placenta helps to resolve its structure and function. In this study, we described the landscape of spatial transcriptome of human placental villi obtained from two pregnant women at the first trimester using the modified Stereo-seq method applied for paraformaldehyde (PFA) fixation samples. The PFA fixation of human placenta villi was better than fresh villi embedded in optimum cutting temperature (OCT) compound, since it greatly improved tissue morphology and the specificity of RNA signals.

The role of Notch signaling in endometrial mesenchymal stromal/stem-like cells maintenance.

Human endometrium undergoes cycles of regeneration in women of reproductive age. The endometrial mesenchymal stromal/stem cells (eMSC) contribute to this process. Notch signaling is essential for homeostasis of somatic stem cells.

Three-dimensional culture models of human endometrium for studying trophoblast-endometrium interaction during implantation.

During implantation, a symphony of interaction between the trophoblast originated from the trophectoderm of the implanting blastocyst and the endometrium leads to a successful pregnancy. Defective interaction between the trophoblast and endometrium often results in implantation failure, pregnancy loss, and a number of pregnancy complications. Owing to ethical concerns of using in vivo approaches to study human embryo implantation, various in vitro culture models of endometrium were established in the past decade ranging from two-dimensional cell-based to three-dimensional extracellular matrix (ECM)/tissue-based culture systems.

Hypoxia Regulates the Self-Renewal of Endometrial Mesenchymal Stromal/Stem-like Cells via Notch Signaling.

Human endometrium is an incredibly dynamic tissue undergoing cyclic regeneration and shedding during a woman's reproductive life. Endometrial mesenchymal stromal/stem-like cells (eMSC) contribute to this process. A hypoxic niche with low oxygen levels has been reported in multiple somatic stem cell types.

WNT5A Interacts With FZD5 and LRP5 to Regulate Proliferation and Self-Renewal of Endometrial Mesenchymal Stem-Like Cells.

Endometrial mesenchymal stem-like cells (eMSC) reside in the basal layer of the endometrium and are responsible for cyclic regeneration during the reproductive lives of women. Myometrial cells act as a component of the niche and regulate the stem cell fate through the activation of WNT/β-catenin signaling WNT5A. Since WNT5A-responsive mechanisms on eMSC are still uncertain, we hypothesize that the WNT ligand-WNT5A works to activate WNT/β-catenin signaling through binding to Frizzled receptors (FZDs) and co-receptor low-density lipoprotein receptor-related protein 5 (LRP5).

Single-cell RNA sequencing of cultured human endometrial CD140bCD146 perivascular cells highlights the importance of in vivo microenvironment.

Background: Endometrial mesenchymal-like stromal/stem cells (eMSCs) have been proposed as adult stem cells contributing to endometrial regeneration. One set of perivascular markers (CD140b&CD146) has been widely used to enrich eMSCs. Although eMSCs are easily accessible for regenerative medicine and have long been studied, their cellular heterogeneity, relationship to primary counterpart, remains largely unclear.

Understanding the regulatory mechanisms of endometrial cells on activities of endometrial mesenchymal stem-like cells during menstruation.

Background: The identification of endometrial stem/progenitor cells in a high turnover rate tissue suggests that a well-orchestrated underlying network controls the behaviour of these stem cells. The thickness of the endometrium can grow from 0.5-1 mm to 5-7 mm within a week indicating the need of stem cells for self-renewal and differentiation during this period.

Myometrial Cells Stimulate Self-Renewal of Endometrial Mesenchymal Stem-Like Cells Through WNT5A/β-Catenin Signaling.

Human endometrium undergoes cycles of proliferation and differentiation throughout the reproductive years of women. The endometrial stem/progenitor cells contribute to this regenerative process. They lie in the basalis layer of the endometrium next to the myometrium.

Co-culture with macrophages enhances the clonogenic and invasion activity of endometriotic stromal cells.

Objective: To study the effect on endometrial and endometriotic cells after co-culture with macrophages, using clonogenic, invasion and self-renewal assays.

Materials And Methods: Peripheral blood samples, endometrium and endometriotic tissues were collected. Autologous macrophages were co-cultured with endometrial and endometriotic cells.

Spatial and temporal characterization of endometrial mesenchymal stem-like cells activity during the menstrual cycle.

The human endometrium is a highly dynamic tissue with the ability to cyclically regenerate during the reproductive life. Endometrial mesenchymal stem-like cells (eMSCs) located throughout the endometrium have shown to functionally contribute to endometrial regeneration. In this study we examine whether the menstrual cycle stage and the location in the endometrial bilayer (superficial and deep portions of the endometrium) has an effect on stem cell activities of eMSCs (CD140bCD146 cells).

Label-retaining stromal cells in mouse endometrium awaken for expansion and repair after parturition.

Human and mouse endometrium undergo dramatic cellular reorganization during pregnancy and postpartum. Somatic stem cells maintain homeostasis of the tissue by providing a cell reservoir for regeneration. We hypothesized that endometrial cells with quiescent properties (stem/progenitor cells) were involved in the regeneration of the endometrial tissue.

Nanoparticle labeling identifies slow cycling human endometrial stromal cells.

Introduction: Evidence suggests that the human endometrium contains stem or progenitor cells that are responsible for its remarkable regenerative capability. A common property of somatic stem cells is their quiescent state. It remains unclear whether slow-cycling cells exist in the human endometrium.

Human female reproductive tract epithelial cell culture.

The female reproductive system is a complex system. Epithelia of the female reproductive system including the ovaries, the oviduct, and the uterus are important sites for follicular development, ovulation, fertilization, implantation, and embryo development. They are also able to synthesize and secrete various hormones, growth factors, and cytokines, which are essential to women's health, sexuality, and reproduction.

Role of label-retaining cells in estrogen-induced endometrial regeneration.

Candidate stem/progenitor cells have been identified in mouse endometrium as label-retaining cells (LRCs). The role of endometrial stem/progenitor cells in initiating estrogen-stimulated endometrial growth in prepubertal and cycling mice was investigated following a single 17β-estradiol (E2) injection in bromodeoxyuridine (BrdU)-labeled and -chased (LRC), ovariectomised mice. Proliferating (BrdU(+)/Ki-67(+)) and mitotic (BrdU(+)/PH3(+)) epithelial LRCs were first detected in prepubertal mice 8 hours following E2 treatment, initiating the proliferative response.

Identification of cells with colony-forming activity, self-renewal capacity, and multipotency in ovarian endometriosis.

Endometriosis, the growth of endometrial tissue outside the uterine cavity, is a common gynecological disorder affecting 10% to 15% of women in their reproductive years. Retrograde menstrual shedding containing endometrial stem/progenitor cells has been postulated to be involved in its pathogenesis. In this study, we identified putative endometriotic stem/progenitor cells by their colony-forming potential, self-renewal capacity, and multipotency.

Glycodelin-A modulates cytokine production of peripheral blood natural killer cells.

Glycodelin-A increased the secretion of interleukin-6, interleukin-13, and granulocyte-macrophage colony-stimulating factor from natural killer cells in the peripheral blood but does not affect their viability, cell death, and cytotoxicity. These data suggest that glycodelin-A contributes to the cytokine shift in early pregnancy.

Up-regulation of endocrine gland-derived vascular endothelial growth factor but not vascular endothelial growth factor in human ectopic endometriotic tissue.

Objective: To study the expression of vascular endothelial growth factor (VEGF), endocrine gland-derived VEGF (EG-VEGF/PK1), and its receptors (PKR1 and PKR2) in eutopic and ectopic endometrial tissues.

Design: A case-control study.

Setting: University reproduction unit.

Hormone and growth factor signaling in endometrial renewal: role of stem/progenitor cells.

The human endometrium is a dynamic remodeling tissue undergoing more than 400 cycles of regeneration, differentiation and shedding during a woman's reproductive years. The co-ordinated and sequential actions of estrogen and progesterone direct these major remodeling events preparing a receptive endometrium for blastocyst implantation on a monthly basis. Adult stem/progenitor cells are likely responsible for endometrial regeneration.

Endometrial stem cells.

Purpose Of Review: The human endometrium is a dynamic tissue, which undergoes cycles of growth and regression with each menstrual cycle. Endometrial regeneration also follows parturition and extensive resection and occurs in postmenopausal women taking estrogen replacement therapy. It is likely that adult stem/progenitor cells are responsible for this remarkable regenerative capacity.

Identification of label-retaining cells in mouse endometrium.

Human and mouse endometrium (lining of the uterus) undergo cycles of growth and regression as part of each reproductive cycle. A well-known method to identify somatic stem/progenitor cells and their location in the stem cell niche is the label-retaining cell (LRC) approach. We hypothesized that mouse endometrium contains small populations of both epithelial and stromal somatic stem/progenitor cells that may be detected by the LRC technique.