• vitro
  • Focused on the gut, our preliminary studies suggest that intestinal stem cell (ISC) numbers are reduced in old mice and humans and that intestinal crypts isolated from old mice are less functional in an in vitro organoid assay of ISC function. (labome.org)
  • Scientists are studying the various components of the niche and trying to replicate the in vivo niche conditions in vitro. (wikipedia.org)
  • In vitro induction of BRAF V600E drove the organoids to derive cystic changes in morphology and promoted adoption of a stem cell niche independency characterized by growth in the absence of added stem cell niche factors including Wnt3a, R-Spondin, and Noggin. (aacrjournals.org)
  • Studies have shown that radial glia in the SGZ express nestin and Sox2, biomarkers associated with neural stem cells, and that isolated radial glia can generate new neurons in vitro. (wikipedia.org)
  • These properties can be illustrated with relative ease in vitro, using methods such as clonogenic assays, where the progeny of a single cell is characterized. (wikipedia.org)
  • It can be induced by modifying the growth medium when stem cells are cultured in vitro or transplanting them to an organ of the body different from the one they were originally isolated from. (wikipedia.org)
  • 2007 Nov;73:1106-10) and "very small embryonic like" - "VSEL" stem cells, and display pluripotency in vitro. (wikipedia.org)
  • CSCs
  • Combined with its role in the protection of CSCs against genotoxic insults, these data strongly put forward the niche as an important target for novel therapies. (aacrjournals.org)
  • However, recent data suggest that tumor cancer stem cells (CSCs) in the stem-cell niches, with self-renewing capacities, might be responsible for tumor initiation, propagation, and recurrence. (hindawi.com)
  • therefore, employing the same logic used for developmental hierarchies, niches that maintain CSCs, should also exist (see refs. (aacrjournals.org)
  • At least two possibilities exist for generating CSC niches: either they are manufactured as nascent domains by tumor cells, or CSCs usurp existing tissue-specific stem cell niches. (aacrjournals.org)
  • Localization of nascent CSC niches is complicated because there are no common anatomical features among tumors ( Fig. 2 ), and consensus is continually shifting about the identity of CSCs. (aacrjournals.org)
  • Although a niche can include a single stem cell, clusters composed of three or more cardiac stem cells (CSCs) and early lineage committed cells (LCCs) were included in the analysis. (ahajournals.org)
  • Young niches contained 6 CSCs while old niches showed 10 CSCs. (ahajournals.org)
  • Apoptosis of CSCs-LCCs increased with age and was restricted to p16 INK4a -positive-cells. (ahajournals.org)
  • However, the fraction of senescent CSCs-LCCs undergoing apoptosis decreased 3.5-fold with age: apoptosis was detected in 7% and 2% of p16 INK4a positive CSCs-LCCs of young and old animals, respectively resulting in the accumulation of senescent cells.Freshly isolated CSCs proliferated in response to growth stimuli but this effect was attenuated in old cells. (ahajournals.org)
  • Collectively, the accumulation of senescent CSCs and the poor response of p16 INK4a- negative CSCs to growth stimuli determined the formation of dysfunctional niches. (ahajournals.org)
  • The decrease in the number of functionally-competent CSCs-LCCs together with the accumulation of senescent CSCs-LCCs limits the ability of CSC niches to repopulate the senescent ventricular myocardium. (ahajournals.org)
  • bone
  • In adults, osteoblasts, responsible for osteogenesis, and hematopoietic cells, responsible for hematopoiesis, are closely associated in the bone marrow, suggesting a reciprocal relationship between the two. (jci.org)
  • In this Review we compare the architecture of these 2 HSC niches in bone marrow. (jci.org)
  • Hematopoiesis of bone cells and marrow stromal cells. (jci.org)
  • Upon each division, 1 daughter cell leaves the bone to proliferate and differentiate into various lineages. (jci.org)
  • HSCs and their progeny are surrounded by stromal cells derived from MSCs, which also reside in the bone cavity. (jci.org)
  • Tian Li and Yaojiong Wu, "Paracrine Molecules of Mesenchymal Stem Cells for Hematopoietic Stem Cell Niche," Bone Marrow Research , vol. 2011, Article ID 353878, 8 pages, 2011. (hindawi.com)
  • Now researchers are reporting in the scientific journal EMBO that the bone marrow niche where HSC's form also ages, contributing to the problem. (eurekalert.org)
  • In a study published March 2, scientists from the University of Ulm in Germany and Cincinnati Children's Hospital Medical Center in the United States propose rejuvenating the bone marrow niche where HSCs are created. (eurekalert.org)
  • Conducting their study in mouse models, the scientists point to cells in the bone marrow called osteoblasts, which help form bone. (eurekalert.org)
  • We show that the place where HSCs form in the bone marrow loses osteopontin upon aging, but if you give back the missing protein to the blood-forming cells they suddenly rejuvenate and act younger," says Hartmut Geiger, PhD, study lead investigator at the Institute for Molecular Medicine and Aging Research Center at the University of Ulm , and the Division of Experimental Hematology and Cancer Biology at Cincinnati Children's. (eurekalert.org)
  • Another experiment monitored levels of osteopontin and other proteins linked to distinct cells in bone marrow during the aging process. (eurekalert.org)
  • Scientists followed up the earlier experiments by transplanting bone marrow cells from older mice (19-21 months) into young mice (8 to 10 weeks). (eurekalert.org)
  • Osteopontin levels are not only low in the bone marrow niche, but also in the blood upon aging. (eurekalert.org)
  • This interaction between Paneth cells and ISCs is mediated by expression in Paneth cells of bone stromal antigen 1 (Bst-1), an ectoenzyme that produces the paracrine factor cyclic ADP ribose (cADPR). (labome.org)
  • Osteoclasts promote the formation of hematopoietic stem cell niches in the bone marrow. (asbmr.org)
  • This niche relocates from the yolk sac to eventually rest in the bone marrow of mammals. (wikipedia.org)
  • In 1978, after observing that the prototypical colony-forming stem cells were less capable at replacing differentiated cells than bone marrow cells injected into irradiated animals, Schofield proposed that a specialized environment in the bone marrow allows these precursor cells to maintain their cellular reconstitution potential. (wikipedia.org)
  • These include the cloning of a cDNA for parathyroid hormone, the identification of a role for parathyroid hormone-related protein in endochondral ossification through Indian hedgehog (IHH) activation, and studies that identified a role for parathyroid hormone in the regulation of the bone marrow stem cell niche. (wikipedia.org)
  • Although such attempts produced no positive benefit, further research found in the mid twentieth century that human cells could be used to help prevent the human body rejecting transplanted organs, leading in time to successful bone marrow transplantation. (wikipedia.org)
  • Bone marrow transplants have been found to be effective, along with some other kinds of human cell therapy - for example in treating damaged knee cartilage. (wikipedia.org)
  • Stem cells from the bone marrow, which is derived from mesoderm, can differentiate into liver, lung, GI tract and skin, which are derived from endoderm and mesoderm. (wikipedia.org)
  • regulate
  • Osteoblasts (expressing M-CSF, RANKL, and OPG and producing IL-7) may regulate lymphoid (expressing IL-7R) and osteoclast (derived from monocytes, expressing the M-CSF ligand c-Fms and RANK) cell development. (jci.org)
  • Cell-cell communication through adherens junctions, cell-ECM communication through integrins, paracrine, juxtacrine, and hormonal signaling, mechanical sensing of physical and geometric constraints, and integration of neural signals are all coordinated to enforce quiescence (red signals) and to tightly regulate self-renewal (green signals). (aacrjournals.org)
  • Several factors are important to regulate stem-cell characteristics within the niche: cell-cell interactions between stem cells, as well as interactions between stem cells and neighbouring differentiated cells, interactions between stem cells and adhesion molecules, extracellular matrix components, the oxygen tension, growth factors, cytokines, and the physicochemical nature of the environment including the pH, ionic strength (e.g. (wikipedia.org)
  • Ependymal cells actively regulate neuronal fate specification of adult neural precursors through release of Noggin. (wikipedia.org)
  • TGFβ The TGFβ family of cytokines regulate the stemness of both normal and cancer stem cells. (wikipedia.org)
  • cellular
  • It was also shown that the two SC compartments acted in accord to maintain a constant cell population and a steady cellular turnover. (wikipedia.org)
  • The objective of this study was to determine whether aging of the heart is characterized by alterations in the cellular composition of cardiac niches and defective cardiomyogenesis. (ahajournals.org)
  • In conclusion, the cellular composition of the niches varies with age. (ahajournals.org)
  • Cell therapy can be defined as therapy in which cellular material is injected into a patient. (wikipedia.org)
  • behavior
  • These approaches can be readily used to dissect the complex molecular interplay of stem cells and their niche and study single-cell behavior in high-throughput. (epfl.ch)
  • Ruth Chiquet-Ehrismann's research focused on the influence of the extracellular matrix on cell behavior, a very new field at the time. (wikipedia.org)
  • vascular
  • In the RMS, vascular cells are arranged parallel to the route of the migrating cells and provide a scaffolding. (wikipedia.org)
  • This vascular membrane is held together by areolar tissue covered by mesothelial cells from the delicate strands of connective tissue called the arachnoid trabeculae. (wikipedia.org)
  • It is also frequently referred to as a vascular, or angiogenic, niche due to the importance and pervasiveness of the blood vessels in the SGZ. (wikipedia.org)
  • vivo
  • However, even these conditions may not truly mimic in vivo niche conditions. (wikipedia.org)
  • Though the concept of stem cell niche was prevailing in vertebrates, the first characterization of stem cell niche in vivo was worked out in Drosophila germinal development. (wikipedia.org)
  • By continuous intravital imaging in mice, researchers were able to explore the structure of the stem cell niche and to obtain the fate of individual stem cells (SCs) and their progeny over time in vivo. (wikipedia.org)
  • A similar dependence of self-renewal potential on proximity to the niche border was reported in the context of hair follicle, in an in vivo live-imaging study. (wikipedia.org)
  • Dexter observed that mesenchymal stromal cells could maintain early HSCs ex vivo, and both Lord and Gong showed that these cells localized to the endosteal margins in long bones. (wikipedia.org)
  • Using in vivo lineage tracing techniques, Lgr5+ cells were found to contribute to the nephron, specifically to the ascending limb of the loop of Henle and the distal convoluted tubule. (wikipedia.org)
  • epithelium
  • Further studies will clarify the signals originating from the ISC niche and determine the processes that control the number and uniform distribution of niches throughout the epithelium. (harvard.edu)
  • The intestinal epithelium is the fastest regenerative tissue in the body, fueled by fast-cycling stem cells. (sigmaaldrich.com)
  • The SSC niche is found in the seminiferous epithelium of mammalian testis, and is primarily constituted of Sertoli and peritubular myoid cells. (wikipedia.org)
  • Although originally thought to arise from the squamous epithelial cell layer covering the ovary, HGSC is now thought to originate in the Fallopian tube epithelium. (wikipedia.org)
  • The glands and intestinal villi are covered by epithelium, which contains multiple types of cells: enterocytes (absorbing water and electrolytes), goblet cells (secreting mucus), enteroendocrine cells (secreting hormones), cup cells, tuft cells, and at the base of the gland, Paneth cells (secreting anti-microbial peptides) and stem cells. (wikipedia.org)
  • Also, new epithelium is formed here, which is important because the cells at this site are continuously worn away by the passing food. (wikipedia.org)
  • regulation
  • Research into human embryonic stem cells is controversial, and regulation varies from country to country, with some countries banning it outright. (wikipedia.org)
  • Feldman's research focuses on regulation of development in meristems/stem cells, root gravitropism, and redox regulation of plant development. (wikipedia.org)
  • The most important somatic cells that support regulation of SSCs are Sertoli cells. (wikipedia.org)
  • Cells present in the testes express molecules that play key roles in the regulation of SSC self-renewal. (wikipedia.org)
  • Fibroblast growth factor (FGF2) is another molecule crucial for the regulation of stem cell renewal and is expressed in Sertoli cells, Leydig cells and germ cells. (wikipedia.org)
  • Chemokine (C-X-C motif) ligand 12 (CXCL12) signaling via its receptor C-X-C chemokine receptor type 4 (CXCR4) is also involved in regulation of SSC fate decisions.CXCL12 is found in Sertoli cells in the basement membrane of the seminiferous tubules in adult mouse testes, and its receptor is expressed in undifferentiated spermatogonial cells. (wikipedia.org)
  • lineages
  • Injection of MKPC into mice post-ischemic injury saw the MKPC regenerating different cell lineages and was able to regenerate renal function and enhanced survival. (wikipedia.org)
  • undergo
  • This includes cells that naturally secrete the relevant therapeutic factors, or which undergo epigenetic changes or genetic engineering that causes the cells to release large quantities of a specific molecule. (wikipedia.org)
  • The large majority of postmitotic neurons undergo apoptosis, or cell death. (wikipedia.org)
  • They undergo symmetric or asymmetric cell division into two daughter cells. (wikipedia.org)
  • Mammalian
  • Here we will explore the emerging effects of diet on nutrient-sensing pathways active in mammalian tissue stem cells and their relevance to normal and cancerous growth. (labome.org)
  • astrocytes
  • Because astrocytes are in close contact with many of the other cells in the SGZ, they are well-suited to serve as sensory and regulatory channels in neurogenesis. (wikipedia.org)
  • Some neural cells are migrated from the SVZ along the rostral migratory stream which contains a marrow-like structure with ependymal cells and astrocytes when stimulated. (wikipedia.org)
  • The astrocytes in the tubes provide support for the migrating cells as well as insulation from electrical and chemical signals released from surrounding cells. (wikipedia.org)
  • The most widely accepted model of an adult NSC is a radial, astrocytes-like, GFAP-positive cell. (wikipedia.org)
  • Signaling
  • Both synthetic and natural biomaterials are reviewed with emphasis on how material-stem cell interactions direct specific signaling pathways and ultimately modulate the cell fate. (springer.com)
  • We have recently demonstrated that CR in young mice augments ISC function by reducing mechanistic target of rapamycin complex 1 (mTORC1) signaling in Paneth cells, and that these effects of CR can be mimicked by rapamycin (an mTORC1 inhibitor). (labome.org)
  • Specifically, we will test the hypotheses that induction of niche Bst-1 by CR and rapamycin boosts ISC function in old mice (Aim 1);that the transcription factor PPAR-gamma mediates this response in Paneth cells (Aim 2);and that cADPR-activated signaling mediates this response in ISCs (Aim 3). (labome.org)
  • Tenascin-C is required for normal Wnt/b-catenin signaling in the whisker follicle stem cell niche. (wikipedia.org)
  • mediate
  • Therefore, successful therapeutic strategies will target the functions that all CSC niches have in common: to mediate self-renewal and to maintain an undifferentiated state and CSC activity even in the presence of cytotoxic agents. (aacrjournals.org)
  • It constitutes a basic unit of tissue physiology, integrating signals that mediate the balanced response of stem cells to the needs of organisms. (wikipedia.org)
  • Regeneration
  • Inactivation of the positive feedback by CRISPR/Cas9 mutation of the binding sequence alters the mosaic stem cell niche pattern and hinders regeneration in organoids. (sigmaaldrich.com)
  • Alternately, it was also reported that differentiated tubular epithelial cells are the driving mechanism for regeneration after injury, using proliferative expansion as the mechanism. (wikipedia.org)
  • interactions
  • Ruth Chiquet-Ehrismann (9 November 1954 - 4 September 2015) was a Swiss biochemist and cell biologist working on interactions in the extracellular matrix. (wikipedia.org)
  • vertebrates
  • Teneurins, a novel family of neuronal cell surface proteins in vertebrates, homologous to the Drosophila pair-rule gene product Ten-m. (wikipedia.org)
  • signals
  • We show that a combination of signals originating from the epidermal cell layer can correctly pattern the key gene expression domains and notably leads to adaptive scaling of these domains to the size of the tissue. (sciencemag.org)
  • Self-renewal of spermatogonial stem cells (SSCs) is regulated by local signals. (wikipedia.org)
  • neurons
  • Under basal conditions, apoptotic corpses of newly generated neurons are rapidly phagocytosed from the niche by unactivated microglia in the adult SGZ. (wikipedia.org)
  • The brain comprises many different types of neurons, but the SGZ generates only one type: granule cells-the primary excitatory neurons in the dentate gyrus (DG)--which are thought to contribute to cognitive functions such as memory and learning. (wikipedia.org)
  • These processes act as a scaffold upon which newly formed neurons can migrate the short distance from the SGZ to the granule cell layer. (wikipedia.org)
  • Neuroblasts represent the last stage of precursor cell development before cells exit the cell cycle and assume their identity as neurons. (wikipedia.org)
  • At this point, after exiting the cell cycle, cells are considered immature neurons. (wikipedia.org)
  • Eventually, the neurons are integrated into the hippocampal circuitry as fully matured granule cells. (wikipedia.org)
  • Some neural stem cells persist in the adult vertebrate brain and continue to produce neurons throughout life. (wikipedia.org)
  • therapies
  • Collectively, this program will yield significant insight and information that will directly translate into optimization of existing cell therapies and development of new ones. (labome.org)
  • therapeutic
  • Nevertheless, these cells are being investigated as the basis for a number of therapeutic applications, including possible treatments for diabetes and Parkinson's disease. (wikipedia.org)
  • There is yet no consensus among biologists on the prevalence and physiological and therapeutic relevance of stem cell plasticity. (wikipedia.org)
  • mice
  • One test in aging mice looked at the formation of endosteum stroma cells, which form a thin layer of connective tissue on the inner surface of bones. (eurekalert.org)
  • Study authors say they observed reduced production of osteoblasts and other stroma cells in the endosteum of older mice. (eurekalert.org)
  • As a follow up to the current study, the researchers are investigating the possibility to use osteopontin replacement therapy in mice to counter the influence of an aging niche directly in the animals. (eurekalert.org)
  • Impressively, testis and neural stem cells from male mice were shown to give rise to lactating mammary glands when transplanted into the mammary fat pad ( 9 , 10 ). (aacrjournals.org)
  • The authors used oc/oc mice, which a loss of osteoclast (OCL) activity, to investigate the role of osteoblasts (OBLs) and OCLs in the development of the hematopoietic stem cell (HSC) niche. (asbmr.org)
  • In mice A Single (As) spermatogonia are capable of creating 2 separate daughter SSCs when they divide or the daughter cells can join and form A Paired (Apr) spermatogonia. (wikipedia.org)
  • morphology
  • Loss of predictable tissue morphology in tumors presents challenges to identifying the CSC niche. (aacrjournals.org)
  • The few that survive begin developing the morphology of hippocampal granule cells, marked by the extension of dendrites into the molecular layer of the DG and the growth of axons into the CA3 region, and subsequently the formation of synaptic connections. (wikipedia.org)
  • Today it is recognized that different matrix proteins influence cell adhesion, cell growth and migration, tissue morphology and signal transduction in specific and decisive ways. (wikipedia.org)