Endometrial Receptivity to Embryo Implantation: Molecular Cues from Functional Genomics (original) (raw)
Related papers
Fertility and Sterility, 2005
To determine whether menstrual cycle stage or activity has an effect on the clonogenic activity of human endometrial epithelial and stromal cells.Clonal analysis of human endometrial epithelial and stromal cells derived from full-thickness endometrium.University research laboratory.Twenty-six women of varying age and race undergoing hysterectomy for nonendometrial pathologies.Full-thickness human endometrial tissue was dissociated into single cells. Epithelial and stromal cells were separated using magnetic beads, and cloning assays were performed in serum-containing or growth factor–supplemented serum-free medium.Clonogenic activity of epithelial and stromal cells.Clonogenicity of epithelial and stromal cells did not vary significantly between proliferative, secretory, and inactive endometrium. However, epithelial and stromal cells did show a trend for greater numbers of clonogenic cells in secretory and proliferative endometrium respectively. A large variation between samples was observed, which may have masked any significant differences.We found that clonogenicity does not vary from the proliferative to secretory stage of the menstrual cycle, or between active, cycling and inactive endometrium for both epithelial and stromal cells. We have demonstrated for the first time that inactive endometrium contains clonogenic epithelial and stromal cells.
Estrogen and progesterone together expand murine endometrial epithelial progenitor cells
STEM CELLS, 2013
Synchronous with massive shifts in reproductive hormones, the uterus and its lining the endometrium expand to accommodate a growing fetus during pregnancy. In the absence of an embryo the endometrium, composed of epithelium and stroma, undergoes numerous hormonally regulated cycles of breakdown and regeneration. The hormonally mediated regenerative capacity of the endometrium suggests that signals that govern the growth of endometrial progenitors must be regulated by estrogen and progesterone. Here, we report an antigenic profile for isolation of mouse endometrial epithelial progenitors. These cells are EpCAM 1 CD44 1 ITGA6 hi Thy1 2 PECAM1 2 PTPRC 2 Ter119 2 , comprise a minor subpopulation of total endometrial epithelia and possess a gene expression profile that is unique and different from other cells of the endometrium. The epithelial progenitors of the endome-trium could regenerate in vivo, undergo multilineage differentiation and proliferate. We show that the number of endometrial epithelial progenitors is regulated by reproductive hormones. Coadministration of estrogen and progesterone dramatically expanded the endometrial epithelial progenitor cell pool. This effect was not observed when estrogen or progesterone was administered alone. Despite the remarkable sensitivity to hormonal signals, endometrial epithelial progenitors do not express estrogen or progesterone receptors. Therefore, their hormonal regulation must be mediated through paracrine signals resulting from binding of steroid hormones to the progenitor cell niche. Discovery of signaling defects in endometrial epithelial progenitors or their niche can lead to development of better therapies in diseases of the endometrium. STEM CELLS 2013;31:808-822
Clonogenicity of Human Endometrial Epithelial and Stromal Cells1
Biology of Reproduction, 2004
The human endometrium regenerates from the lower basalis layer, a germinal compartment that persists after menstruation to give rise to the new upper functionalis layer. Because adult stem cells are present in tissues that undergo regeneration, we hypothesized that human endometrium contains small populations of epithelial and stromal stem cells responsible for cyclical regeneration of endometrial glands and stroma and that these cells would exhibit clonogenicity, a stem-cell property. The aims of this study were to determine 1) the clonogenic activity of human endometrial epithelial and stromal cells, 2) which growth factors support this clonogenic activity, and 3) determine the cellular phenotypes of the clones. Endometrial tissue was obtained from women undergoing hysterectomy. Purified singlecell suspensions of epithelial and stromal cells were cultured at cloning density (300-500/cm 2) in serum medium or in serumfree medium supplemented with one of eight growth factors. Small numbers of epithelial (0.22%) and stromal cells (1.25%) initiated colonies in serum-containing medium. The majority of colonies were small, containing large, loosely arranged cells, and 37% of epithelial and 1 in 60 of stromal colonies were classified as large, comprising small, densely packed cells. In serum-free medium, transforming growth factor-␣ (TGF␣), epidermal growth factor (EGF), platelet-derived growth factor-BB (PDGF-BB) strongly supported clonogenicity of epithelial cells, while leukemia-inhibitory factor (LIF), hepatocyte growth factor (HGF), stem-cell factor (SCF), insulin-like growth factor-I (IGF-I) were weakly supportive, and basic fibroblast growth factor (bFGF) was without effect. TGF␣, EGF, PDGF-BB, and bFGF supported stromal cell clonogenicity, while HGF, SCF, LIF, and IGF-I were without effect. Small epithelial colonies expressed three epithelial markers but not stromal markers; however, large epithelial colonies showed little reactivity for all markers except ␣ 6-integrin. All stromal colonies contained fibroblasts, expressing stromal markers, and in some colonies, myofibroblasts were also identified. This analysis of human endometrium has demonstrated the presence of rare clonogenic epithelial and stromal cells with high proliferative potential, providing the first evidence for the existence of putative endometrial epithelial and stromal stem cells.
Clonogenicity of Human Endometrial Epithelial and Stromal Cells
Biology of Reproduction, 2004
The human endometrium regenerates from the lower basalis layer, a germinal compartment that persists after menstruation to give rise to the new upper functionalis layer. Because adult stem cells are present in tissues that undergo regeneration, we hypothesized that human endometrium contains small populations of epithelial and stromal stem cells responsible for cyclical regeneration of endometrial glands and stroma and that these cells would exhibit clonogenicity, a stem-cell property. The aims of this study were to determine 1) the clonogenic activity of human endometrial epithelial and stromal cells, 2) which growth factors support this clonogenic activity, and 3) determine the cellular phenotypes of the clones. Endometrial tissue was obtained from women undergoing hysterectomy. Purified singlecell suspensions of epithelial and stromal cells were cultured at cloning density (300-500/cm 2 ) in serum medium or in serumfree medium supplemented with one of eight growth factors. Small numbers of epithelial (0.22%) and stromal cells (1.25%) initiated colonies in serum-containing medium. The majority of colonies were small, containing large, loosely arranged cells, and 37% of epithelial and 1 in 60 of stromal colonies were classified as large, comprising small, densely packed cells. In serum-free medium, transforming growth factor-␣ (TGF␣), epidermal growth factor (EGF), platelet-derived growth factor-BB (PDGF-BB) strongly supported clonogenicity of epithelial cells, while leukemia-inhibitory factor (LIF), hepatocyte growth factor (HGF), stem-cell factor (SCF), insulin-like growth factor-I (IGF-I) were weakly supportive, and basic fibroblast growth factor (bFGF) was without effect. TGF␣, EGF, PDGF-BB, and bFGF supported stromal cell clonogenicity, while HGF, SCF, LIF, and IGF-I were without effect. Small epithelial colonies expressed three epithelial markers but not stromal markers; however, large epithelial colonies showed little reactivity for all markers except ␣ 6 -integrin. All stromal colonies contained fibroblasts, expressing stromal markers, and in some colonies, myofibroblasts were also identified. This analysis of human endometrium has demonstrated the presence of rare clonogenic epithelial and stromal cells with high proliferative potential, providing the first evidence for the existence of putative endometrial epithelial and stromal stem cells.
Effect of estrogen on human endometrial epithelial cell growth and differentiation in vitro
Steroids, 1991
Although physiologic parameters regulating endometrialproliferation and secretory maturation during the normal menstrual cycle are well characterized, cellular and molecular interactions directing these events under the inj?uence of a changing hormonal milieu remain unclear. in the present study, the effect of estradiol on the growth and acquisition of diff erentiated function of pur$ed endometr~al epithel~um was examined in an established model. ~pithelial ceils were isolated with high purity from human endometrial biopsies. When cultured on a biomatrix bed, cells established a polarized monolayer with gland-like invaginations. Cells isolated throughout the menstrual cycle were cultured under serumfree conditions, with or without estradiol, and secretion of tumor-associated epitope TAG-72 was monitored by radioimmunoassay. Under steroid-free conditions, cells exhibited a distinct proliferative interval, followed by the a&qu~sition of TAG-72 epitope secretory capabili~. Although estradiol had no apparent effect on proliferation or spatial organization of epithelial cells, a striking inhibition of TAG-72 epitope secretion was evident. This observation is believed to represent a direct effect of estradiol on endometrial epithelial cells in this model.
Endometrial regeneration and endometrial stem/progenitor cells
Reviews in Endocrine and Metabolic Disorders, 2012
The human uterus is a highly dynamic organ with peculiar plasticity and marked reproductive ability, due to the presence of a vast number of multiple stem/progenitor cell types, including endometrial, stromal and vascular progenitor cells. Conflicting results have been published regarding which uterine population might represent the real stem/progenitor cell fraction in terms of in vivo stem cell activity. Human endometrial side population (ESP) cells were shown to differentiate into multiple endometrial lineages in the stem cell niche provided by whole endometrial cells, suggesting that ESP cells might represent the most important stem/progenitor cells responsible of the cyclical regeneration of the endometrium throughout a woman's reproductive life. This study was aimed at analyzing the localization, composition, and occurrence of stem cell niches in the human fetal uterus at different stages of development. To this end, the whole uterus was obtained at autopsy by 12 human fetuses and newborns, ranging in gestational age from 12 up to 39 weeks of gestation. Tissue paraffin sections were immunostained with antibodies against insulin gene enhancer protein (ISL-1), a transcription factor previously utilized as a marker of stem/progenitor cells in the pancreas, heart and nervous system. Reactivity for ISL-1 was detected in both epithelial and stromal uterine precursors, at all gestational ages, allowing the detection of uterine progenitor cells. The loss of reactivity for ISL-1 in some stromal cell precursors was interpreted as a sign of differentiation. These preliminary data indicate ISL-1 as a useful marker for the detection of stem/progenitor cells in the human fetal endometrium. Further studies are needed to verify the utility of ISL-1 as a marker of stem/progenitor cells in the adult endometrium.
Session 17: Endometrial Biology in Endometriosis and Implantation
Human Reproduction, 2010
The human endometrium has a remarkable capacity for efficient, cyclical repair throughout the reproductive years of a woman's life. The inflammation of menstruation completely resolves without scarring or loss of function. Factors involved in endometrial repair, and their regulation, have yet to be fully elucidated. Aberrations in the repair process may lead to significant pathology, such as heavy menstrual bleeding. Adrenomedullin (ADM) is a pluripotent peptide known to be involved in angiogenesis and regulation of cell growth. Therefore, ADM is an attractive candidate for endometrial repair. Repair of the human endometrium commences on day two of the cycle, during active bleeding. Pre-menstrually progesterone (P) levels fall as the corpus luteum regresses. This P-withdrawal increases endometrial prostaglandin (PG) production and causes vasoconstriction of the spiral arterioles, leading to an episode of transient hypoxia. Recent array data from our laboratory (unpublished) has identified ADM as a target gene up-regulated by PGF 2α. aims: (1) to define endometrial expression of adrenomedullin (ADM) across the menstrual cycle (2) to determine the role of prostaglandins and hypoxia in the regulation of this vasoactive and mitogenic factor with a putative role in endometrial repair. methods: Endometrial biopsies were collected with ethical approval and consent from healthy, normally cycling women. Biopsies were categorised as menstrual (n = 5) proliferative (n = 11), early-(n = 7), mid-(n = 6) and latesecretory (n = 6) based on day of cycle, histological dating and serum oestrogen and P levels on day of biopsy. Endometrial explants and endometrial epithelial (Ishikawa) cells were exposed to 100nM PGE 2 , 100nM PGF 2α and/or 0.5% O 2. Additional proliferative explants (n = 4) were subjected to an in vitro model of P-withdrawal using sequential 1μM medroxyprogesterone acetate and 1μM mifepristone (a progesterone receptor antagonist). Gene expression was examined by Q-RT-PCR and protein levels by ELISA. results: ADM mRNA expression was significantly increased in endometrium from the menstrual phase of the cycle (p < 0.01). Culture of secretory endometrial explants with PGF 2α or in hypoxic conditions displayed an up-regulation in ADM mRNA expression. Treatment of proliferative explants revealed no such upregulation, indicating the need for prior P exposure. PGE 2 had no significant effect on ADM expression in any explants, regardless of stage of cycle. Proliferative biopsies subjected to in vitro P-withdrawal showed significant up-regulation of ADM, but only in the presence of hypoxia (p < 0.05). Addition of 8.4μM indomethacin (COX inhibitor), attenuated this increase in ADM expression. Endometrial epithelial cells treated with PGF 2α or hypoxia showed up-regulation of ADM mRNA and protein expression (p < 0.05). In contrast, no changes were observed after PGE 2 treatment. Echinomycin, an inhibitor of hypoxia inducible factor-1, attenuated both PGF 2α and hypoxia induced ADM mRNA expression in a dose dependent manner. conclusions: Herein, we have demonstrated significantly increased endometrial expression of ADM at menstruation. As endometrial repair is initiated during active bleeding, this finding is consistent with ADM having a role in endometrial repair. Up-regulation of ADM expression follows P-withdrawal but appears to be dependent upon the downstream events of hypoxia and prostaglandin production. We reveal the specific contribution of PGF 2α to ADM up-regulation, with PGE 2 having no significant effect. PGF 2α and hypoxia mediated up-regulation of ADM both appear to be via induction of the transcription factor, HIF-1. These novel data on the expression and regulation of endometrial ADM further delineate the physiological mechanisms involved in endometrial repair and are a prerequisite for research into common gynaecological pathologies such as heavy menstrual bleeding. o-065 Homeobox a7 regulates estrogen receptor alpha expression and proliferation in human endometrial cell
Establishment and morphologic characterization of normal human endometrium in vitro
In Vitro, 1984
Tissue culture offers a model system with which to study the endocrine-mediated growth, differentiation, and metabolic activities of the endometrium. We have established and continue to maintain monolayer cultures of normal human endometrial epithelial cells from each phase of the menstrual cycle. At present, eight proliferative, two secretory, and two menstrual phase cultures have been established. These have been passed at least three times. One proliferative phase culture has been growing for 18 mo, and passed l0 times. Colonies of epithelioid cells as well as single cells appear in the cultures within 2 to 8 h of initial culture and maintain this appearance throughout long-term growth. The cells are periodic acid Schiff positive for carbohydrates and positive for keratin, an immunochemical marker for epithelial tissues. Studies comparing the uhrastructure of the cultures with fresh endometrial tissue revealed morphologic features common to both, including prominent nucleoli, Golgi, mitochondria-rough endoplasmic reticulum complexes, and abundant glycogen. The cells are not tumorigenic in the nude mouse and do not form colonies on soft agarose, confirming the nonneoplastic identity of the cells.