Concise Review: Understanding the Renal Progenitor Cell Niche In Vivo to Recapitulate Nephrogenesis In Vitro

Abstract Development of hematopoietic stem cells (HSCs) and their immediate progeny is maintained by the interaction with cells in the microenvironment. We found that hematopoiesis was dysregulated in Id1−/− mice. Although the frequency of HSCs in Id1−/− bone marrow was increased, their total numbers remained unchanged as the result of decreased bone marrow cellularity. In addition, the ability of Id1−/− HSCs to self-renew was normal, suggesting Id1 does not affect HSC function. Id1−/− progenitors showed increased cycling in vivo but not in vitro, suggesting cell nonautonomous mechanisms for the increased cycling. Id1−/− HSCs developed normally when transplanted into Id1+/+ mice, whereas the development of Id1+/+ HSCs was impaired in Id1−/− recipients undergoing transplantation and reproduced the hematologic features of Id1−/− mice, indicating that the Id1−/− microenvironment cannot support normal hematopoietic development. Id1−/− stromal cells showed altered production of cytokines in vitro, and cytokine levels were deregulated in vivo, which could account for the Id1−/− hematopoietic phenotypes. Thus, Id1 is required for regulating the hematopoietic progenitor cell niche but is dispensable for maintaining HSCs.

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Bone Marrow Niches for Skeletal Progenitor Cells and their Inhabitants in Health and Disease

Current Stem Cell Research & Therapy ◽

10.2174/1574888x14666190123161447 ◽

2019 ◽

Vol 14 (4) ◽

pp. 305-319 ◽

Cited By ~ 4

Author(s):

Marietta Herrmann ◽

Franz Jakob

Keyword(s):

Bone Marrow ◽

Progenitor Cells ◽

Progenitor Cell ◽

Adult Stem Cells ◽

Current Knowledge ◽

Cell Populations ◽

Surface Markers ◽

Bone Marrow Niches

The bone marrow hosts skeletal progenitor cells which have most widely been referred to as Mesenchymal Stem or Stromal Cells (MSCs), a heterogeneous population of adult stem cells possessing the potential for self-renewal and multilineage differentiation. A consensus agreement on minimal criteria has been suggested to define MSCs in vitro, including adhesion to plastic, expression of typical surface markers and the ability to differentiate towards the adipogenic, osteogenic and chondrogenic lineages but they are critically discussed since the differentiation capability of cells could not always be confirmed by stringent assays in vivo. However, these in vitro characteristics have led to the notion that progenitor cell populations, similar to MSCs in bone marrow, reside in various tissues. MSCs are in the focus of numerous (pre)clinical studies on tissue regeneration and repair.Recent advances in terms of genetic animal models enabled a couple of studies targeting skeletal progenitor cells in vivo. Accordingly, different skeletal progenitor cell populations could be identified by the expression of surface markers including nestin and leptin receptor. While there are still issues with the identity of, and the overlap between different cell populations, these studies suggested that specific microenvironments, referred to as niches, host and maintain skeletal progenitor cells in the bone marrow. Dynamic mutual interactions through biological and physical cues between niche constituting cells and niche inhabitants control dormancy, symmetric and asymmetric cell division and lineage commitment. Niche constituting cells, inhabitant cells and their extracellular matrix are subject to influences of aging and disease e.g. via cellular modulators. Protective niches can be hijacked and abused by metastasizing tumor cells, and may even be adapted via mutual education. Here, we summarize the current knowledge on bone marrow skeletal progenitor cell niches in physiology and pathophysiology. We discuss the plasticity and dynamics of bone marrow niches as well as future perspectives of targeting niches for therapeutic strategies.

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MESENCHYMAL TNFR1 EXPRESSION PRESERVES THE COLONIC EPITHELIAL STEM CELL NICHE

Inflammatory Bowel Diseases ◽

10.1093/ibd/izaa347.018 ◽

2021 ◽

Vol 27 (Supplement_1) ◽

pp. S7-S8

Author(s):

Safina Gadeock ◽

Cambrian Liu ◽

Brent Polk

Keyword(s):

Stem Cell ◽

Stem Cell Niche ◽

Mesenchymal Cells ◽

Epithelial Stem Cells ◽

Epithelial Stem Cell ◽

Long Term Treatment ◽

Lgr5 Expression ◽

Cell Niche

Abstract Tumor necrosis factor (TNF) is a highly expressed cytokine in inflammatory bowel disease (IBD). Although TNF can induce colonic epithelial dysfunction and apoptosis, recent studies suggest that TNF signalling promotes epithelial wound repair and stem cell function. Here we investigated the role of TNF receptor 1 (TNFR1) in mediating TNF’s effects on colonic epithelial stem cells, integral to mucosal healing in colitis. We demonstrate that Tnfr1-/- mice exhibit loss in Lgr5 expression (-52%, p<0.02; N=6) compared to wildtype (WT) controls. However, the opposite result was found in vitro, wherein murine Tnfr1-/- colonoids demonstrated a significant increase in Lgr5 expression (66%, p<0.007; N=6) compared to WT colonoids. Similarly, human colonoids treated with an anti-TNFR1 antibody also demonstrated an increase in Lgr5 expression, relative to IgG controls. To resolve the contradiction in the in vivo versus in vitro environment, we hypothesized that mesenchymal TNFR1 expression regulates the epithelial stem cell niche. To determine the relationships between these cell types, we co-cultured WT or Tnfr1-/- colonoids with WT or Tnfr1-/- colonic myofibroblasts (CMFs). We found that epithelial Lgr5 expression was significantly higher (by 52%, p<0.05; N=3) when co-cultured with WT compared to TNFR1-/- myofibroblasts. The loss of TNFR1 expression in vivo increases the number of αSMA+ mesenchymal cells by nearly 56% (N=6) but considerably reduces the pericryptal PDGFRα+ cells, suggesting modifications in mesenchymal populations that contribute to the epithelial stem cell niche. Functionally, primary Tnfr1-/--CMFs displayed PI3k (p<0.001; N=3) and MAPK (p<0.01; N=3)-dependent increases in migration, proliferation, and differentiation, but RNA profiling demonstrated by diminished levels of stem cell niche factors, Rspo3 (-80%, p<0.0001; N=6) and Wnt2b (-63%, p<0.008; N=6) compared to WT-CMFs. Supplementation with 50ng recombinant Rspo3 for 5 d to Lgr5-GFP organoids co-cultured with TNFR1-/--CMFs restored Lgr5 expression to wildtype levels. Therefore, TNFR1-mediated TNF signalling in mesenchymal cells promotes their ability to support an epithelial stem cell niche. These results should motivate future studies of the stem cell niche in the context of long-term treatment with anti-TNF therapies.

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Functional regeneration and repair of tendons using biomimetic scaffolds loaded with recombinant periostin

Nature Communications ◽

10.1038/s41467-021-21545-1 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Yu Wang ◽

Shanshan Jin ◽

Dan Luo ◽

Danqing He ◽

Chunyan Shi ◽

...

Keyword(s):

Progenitor Cell ◽

Transcriptional Profiling ◽

Collagen Scaffold ◽

Defect Model ◽

Tendon Regeneration ◽

Biomimetic Scaffolds ◽

Functional Regeneration

AbstractTendon injuries disrupt the balance between stability and mobility, causing compromised functions and disabilities. The regeneration of mature, functional tendons remains a clinical challenge. Here, we perform transcriptional profiling of tendon developmental processes to show that the extracellular matrix-associated protein periostin (Postn) contributes to the maintenance of tendon stem/progenitor cell (TSPC) functions and promotes tendon regeneration. We show that recombinant periostin (rPOSTN) promotes the proliferation and stemness of TSPCs, and maintains the tenogenic potentials of TSPCs in vitro. We also find that rPOSTN protects TSPCs against functional impairment during long-term passage in vitro. For in vivo tendon formation, we construct a biomimetic parallel-aligned collagen scaffold to facilitate TSPC tenogenesis. Using a rat full-cut Achilles tendon defect model, we demonstrate that scaffolds loaded with rPOSTN promote endogenous TSPC recruitment, tendon regeneration and repair with native-like hierarchically organized collagen fibers. Moreover, newly regenerated tendons show recovery of mechanical properties and locomotion functions.

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X-chromosome reactivation: a concise review

Biochemical Society Transactions ◽

10.1042/bst20210777 ◽

2021 ◽

Author(s):

Alessandra Spaziano ◽

Dr Irene Cantone

Keyword(s):

X Chromosome ◽

X Chromosome Inactivation ◽

Epigenetic Modifications ◽

X Chromosomes ◽

Cell Divisions ◽

Concise Review ◽

Inactive X Chromosome ◽

Silencing Pathways

Mammalian females (XX) silence transcription on one of the two X chromosomes to compensate the expression dosage with males (XY). This process — named X-chromosome inactivation — entails a variety of epigenetic modifications that act synergistically to maintain silencing and make it heritable through cell divisions. Genes along the inactive X chromosome are, indeed, refractory to reactivation. Nonetheless, X-chromosome reactivation can occur alongside with epigenome reprogramming or by perturbing multiple silencing pathways. Here we review the events associated with X-chromosome reactivation during in vivo and in vitro reprogramming and highlight recent efforts in inducing Xi reactivation by molecular perturbations. This provides us with a first understanding of the mechanisms underlying X-chromosome reactivation, which could be tackled for therapeutic purposes.

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Persistence of myeloid progenitor cells expressing BCR-ABL mRNA after allogeneic bone marrow transplantation for chronic myelogenous leukemia

Blood ◽

10.1182/blood.v84.7.2109.bloodjournal8472109 ◽

1994 ◽

Vol 84 (7) ◽

pp. 2109-2114

Author(s):

G Pichert ◽

EP Alyea ◽

RJ Soiffer ◽

DC Roy ◽

J Ritz

Keyword(s):

Bone Marrow ◽

Bone Marrow Transplantation ◽

Marrow Transplantation ◽

Progenitor Cell ◽

Allogeneic Bone Marrow Transplantation ◽

Allogeneic Bone Marrow ◽

Myeloid Differentiation ◽

Allogeneic Bone

Previous studies have shown that tumor-specific bcr-abl mRNA can often be detected by polymerase chain reaction. (PCR) for months to years after allogeneic bone marrow transplantation (BMT) for chronic myelocytic leukemia (CML). Nevertheless, the presence of bcr-abl mRNA by itself does not invariably predict for clinical relapse post-BMT. This has led to the hypothesis that bcr-abl mRNA might be expressed in cells that have lost either proliferative or myeloid differentiation potential. To directly characterize the cells detected by PCR in patients with CML after allogeneic BMT, we first identified five individuals in whom PCR-positive cells could be detected at multiple times post-BMT. Bone marrow samples from these individuals were cultured in vitro and single erythroid, granulocytic, and macrophage colonies, each containing 50 to 100 cells, were examined for the presence of bcr-abl mRNA by PCR. PCR-positive myeloid colonies could be detected in four of five individuals in marrow samples obtained 5 to 56 months post-BMT. Overall, 7 of 135 progenitor cell colonies (5.2%) were found to be PCR-positive. The expression of bcr-abl mRNA appeared to be equally distributed among committed erythroid, macrophage, and granulocyte progenitors. These patients have now been followed-up for an additional 20 to 33 months from the time of progenitor cell PCR analysis but only one of these individuals has been found to have cytogenetic evidence of recurrent Ph+ cells. These results show that long-term persistence of PCR-detectable bcr-abl mRNA after allogeneic BMT can be caused by the persistence of CML-derived clonogenic myeloid precursors that have survived the BMT preparative regimen. These cells continue to have both proliferative and myeloid differentiation capacity in vitro. Nevertheless, these PCR-positive cells do not appear to either expand or differentiate in vivo for prolonged periods, suggesting the presence of mechanisms for suppression of residual clonogenic leukemia cells in vivo.

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Abstract 356: Krueppel-Like Factor 15 Regulates Wnt/β-Catenin Transcription and Controls Cardiac Progenitor Cell Fate in the Postnatal Heart

Circulation Research ◽

10.1161/res.111.suppl_1.a356 ◽

2012 ◽

Vol 111 (suppl_1) ◽

Author(s):

Claudia Noack ◽

Maria P Zafiriou ◽

Anke Renger ◽

Hans J Schaeffer ◽

Martin W Bergmann ◽

...

Keyword(s):

Cell Fate ◽

Transcriptional Activation ◽

Progenitor Cell ◽

Cellular Localization ◽

Target Genes ◽

Critical Role ◽

Isolated Cells ◽

Cardiac Progenitor Cell

Wnt/β-catenin signaling controls adult heart remodeling partly by regulating cardiac progenitor cell (CPC) differentiation. We now identified and characterized a novel cardiac interaction of the transcription factor Krueppel-like factor 15 (KLF15) with the Wnt/β-catenin signaling on adult CPCs. In vitro mutation, reporter gene assays and co-localization studies revealed that KLF15 requires two distinct domains for nuclear localization and for repression of β-catenin-mediated transcription. KLF15 had no effect on β-catenin stability or cellular localization, but interacted with its co-factor TCF4, which is required for activation of β-catenin target gene expression. Moreover, increased TCF4 ubiquitination was induced by KLF15. In line with this finding we found KLF15 to interact with the Nemo-like kinase, which was shown to phosphorylate and target TCF4 for degradation. In vivo analyses of adult Klf15 functional knock-out (KO) vs. wild-type (WT) mice showed a cardiac β-catenin-mediated transcriptional activation and reduced TCF4 degradation along with cardiac dysfunction assessed by echocardiography (n=10). FACS analysis of the CPC enriched-population of KO vs. WT mice revealed a significant reduction of cardiogenic-committed precursors identified as Sca1+/αMHC+ (0.8±0.2% vs. 1.8±0.1%) and Tbx5+ (3.5±0.3% vs. 5.2±0.5%). In contrast, endothelial Sca1+/CD31+ cells were significantly higher in KO mice (11.3±0.4% vs. 8.6±0.4%; n≥9). In addition, Sca1+ isolated cells of Klf15 KO showed increased RNA expression of endothelial markers von Willebrand Factor, CD105, and Flk1 along with upregulation of β-catenin target genes. CPCs co-cultured on adult fibroblasts resulted in increased endothelial Flk1 cells and reduction of αMHC and Hand1 cardiogenic cells in KO vs. WT CPCs (n=9). Treating these co-cultures with Quercetin, an inhibitor of nuclear β-catenin, resulted in partial rescue of the observed phenotype. This study uncovers a critical role of KLF15 for the maintenance of cardiac tissue homeostasis. Via inhibition of β-catenin transcription, KLF15 controls cardiomyogenic cell fate similar to embryonic cardiogenesis. This knowledge may provide a tool for activation of endogenous CPCs in the postnatal heart.

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Proliferation and differentiation potential of rat forebrain oligodendroglial progenitors both in vitro and in vivo

Development ◽

10.1242/dev.111.4.1061 ◽

1991 ◽

Vol 111 (4) ◽

pp. 1061-1080 ◽

Cited By ~ 7

Author(s):

R. Hardy ◽

R. Reynolds

Keyword(s):

Progenitor Cell ◽

Neonatal Rat ◽

Myelin Proteins ◽

Brdu Incorporation ◽

Cell Type ◽

Differentiation Potential ◽

Serum Free ◽

Rat Forebrain

We have followed the development of the O-2A progenitor cell from the neonatal rat forebrain, both in dissociated cell culture and in cryostat sections, using immunocytochemical techniques employing a panel of antibodies that recognise the cells at different stages of their development. This included the monoclonal antibody LB1, which binds to the surface ganglioside GD3 expressed on O-2A progenitor cells. In secondary cultures enriched for O-2A progenitors maintained in a serum-free chemically defined medium, a large proportion of the cells are primed to differentiate into oligodendroglia and go on to express the oligodendroglial specific surface glycolipid galactocerebroside (GC) and then the myelin proteins CNP and MBP. However, a significant proportion of immature bipolar GD3+ cells remained after 6 days in secondary culture. It appears that not all the O-2A progenitors in our cultures differentiate immediately and some cells remain in an undifferentiated state and divide to replenish progenitor numbers. We have also identified in our cultures a small apolar GD3- cell, which when isolated differentiated into a GD3+ bipolar O-2A progenitor cell. We have termed this cell type a preprogenitor. The differentiation of this cell type into O-2A progenitors may be the source of the immature GD3+ cells present at the later stages of our secondary cultures. The proliferative profile of the cultures was studied using 5′bromo-2-deoxyuridine (BrdU) incorporation as an index of mitosis. Only the immature, bipolar O-2A progenitors were seen to divide at any time in serum-free culture. Neither the more mature multipolar O-2A cells nor the oligodendroglia were seen to divide. The developmental profile of the O-2A cells in the rat forebrain in vivo showed a largely similar progression to that in culture, with a time lag of at least 6 days between GD3 expression and the onset of myelination. BrdU incorporation studies in vivo also showed that the GD3+ progenitor cell is mitotic whereas the GC(+)-expressing oligodendroglia is not. We have shown that there are several significant alterations in the timing of antigen expression in both O-2A progenitors and oligodendroglia in vitro compared to that seen in vivo.

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On the induction of fetal hemoglobin by butyrates: in vivo and in vitro studies with sodium butyrate and comparison of combination treatments with 5-AzaC and AraC

Blood ◽

10.1182/blood.v74.6.1963.1963 ◽

1989 ◽

Vol 74 (6) ◽

pp. 1963-1971 ◽

Cited By ~ 79

Author(s):

P Constantoulakis ◽

G Knitter ◽

G Stamatoyannopoulos

Keyword(s):

Sodium Butyrate ◽

Progenitor Cell ◽

Fetal Hemoglobin ◽

Globin Genes ◽

Cell Numbers ◽

Gamma Globin ◽

Combination Treatments ◽

Bone Marrow Cultures

Abstract To obtain information on the cellular mechanism of induction of fetal hemoglobin (HbF) by sodium butyrate (NaB), we treated adult baboons with NaB and assessed its effects on HbF expression. Infusion of NaB increased F reticulocytes and F-positive CFUe and e-cluster colonies without induction of reticulocytosis or increase in progenitor cell numbers. Addition of NaB in bone marrow cultures increased the frequency of F-positive CFUe and e-clusters without increasing progenitor cell numbers. NaB induced HbF in human adult BFUe cultures and increased the gamma/gamma + beta globin chain and mRNA ratios in short-term incubations of culture-derived erythroblasts. There was a synergistic induction of HbF by NaB and 5-azacytidine (5-azaC), but not when the animal was treated with NaB and cytarabine (AraC). Our results suggest that the activation of gamma-globin expression by NaB reflects an action of this compound on globin genes or globin chromatin.

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Lithium stimulation of granulopoiesis in diffusion chambers--a model of a humoral, indirect stimulation of stem cell proliferation

Blood ◽

10.1182/blood.v65.1.163.163 ◽

1985 ◽

Vol 65 (1) ◽

pp. 163-168 ◽

Cited By ~ 9

Author(s):

MA Doukas ◽

EO Niskanen ◽

PJ Quesenberry

Keyword(s):

Progenitor Cell ◽

Rest Period ◽

Direct Effects ◽

Diffusion Chambers ◽

Macrophage Colony ◽

Chamber Fluid ◽

Indirect Stimulation ◽

Stimulation Of

Abstract Lithium has been recognized as a stimulator of granulopoiesis both in vivo and in vitro. The mechanism by which lithium provokes this stimulation is unclear, with previous data focusing on such divergent causes as direct effects on progenitor cells v elevations in granulocyte macrophage colony-stimulating activity (GM-CSA) production. In the present study, we used a model system of granulopoiesis in diffusion chambers to study this stimulation of granulopoiesis. Lithium pretreatment of mice followed by a rest period to allow for excretion of the lithium (confirmed by serum assays) revealed a stimulation of progenitor cell growth within the diffusion chambers. No changes in the serum and chamber fluid GM-CSA levels were discernible between the control host mice and the lithium-pretreated mice. These data indicate that lithium stimulates granulopoiesis by an indirect mechanism that does not appear to involve GM-CSA.

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