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Sample records for epidermal progenitor cell

  1. Microtubules CLASP to Adherens Junctions in epidermal progenitor cells.

    PubMed

    Shahbazi, Marta N; Perez-Moreno, Mirna

    2014-01-01

    Cadherin-mediated cell adhesion at Adherens Junctions (AJs) and its dynamic connections with the microtubule (MT) cytoskeleton are important regulators of cellular architecture. However, the functional relevance of these interactions and the molecular players involved in different cellular contexts and cellular compartments are still not completely understood. Here, we comment on our recent findings showing that the MT plus-end binding protein CLASP2 interacts with the AJ component p120-catenin (p120) specifically in progenitor epidermal cells. Absence of either protein leads to alterations in MT dynamics and AJ functionality. These findings represent a novel mechanism of MT targeting to AJs that may be relevant for the maintenance of proper epidermal progenitor cell homeostasis. We also discuss the potential implication of other MT binding proteins previously associated to AJs in the wider context of epithelial tissues. We hypothesize the existence of adaptation mechanisms that regulate the formation and stability of AJs in different cellular contexts to allow the dynamic behavior of these complexes during tissue homeostasis and remodeling. PMID:24522006

  2. Microtubules CLASP to Adherens Junctions in epidermal progenitor cells

    PubMed Central

    Shahbazi, Marta N; Perez-Moreno, Mirna

    2014-01-01

    Cadherin-mediated cell adhesion at Adherens Junctions (AJs) and its dynamic connections with the microtubule (MT) cytoskeleton are important regulators of cellular architecture. However, the functional relevance of these interactions and the molecular players involved in different cellular contexts and cellular compartments are still not completely understood. Here, we comment on our recent findings showing that the MT plus-end binding protein CLASP2 interacts with the AJ component p120-catenin (p120) specifically in progenitor epidermal cells. Absence of either protein leads to alterations in MT dynamics and AJ functionality. These findings represent a novel mechanism of MT targeting to AJs that may be relevant for the maintenance of proper epidermal progenitor cell homeostasis. We also discuss the potential implication of other MT binding proteins previously associated to AJs in the wider context of epithelial tissues. We hypothesize the existence of adaptation mechanisms that regulate the formation and stability of AJs in different cellular contexts to allow the dynamic behavior of these complexes during tissue homeostasis and remodeling. PMID:24522006

  3. SNAI2 controls the undifferentiated state of human epidermal progenitor cells.

    PubMed

    Mistry, Devendra S; Chen, Yifang; Wang, Ying; Zhang, Kang; Sen, George L

    2014-12-01

    The transcription factor, SNAI2, is an inducer of the epithelial to mesenchymal transition (EMT) which mediates cell migration during development and tumor invasion. SNAI2 can also promote the generation of mammary epithelial stem cells from differentiated luminal cells when overexpressed. How SNAI2 regulates these critical and diverse functions is unclear. Here, we show that the levels of SNAI2 expression are important for epidermal cell fate decisions. The expression of SNAI2 was found to be enriched in the basal layer of the interfollicular epidermis where progenitor cells reside and extinguished upon differentiation. Loss of SNAI2 resulted in premature differentiation whereas gain of SNAI2 expression inhibited differentiation. SNAI2 controls the differentiation status of epidermal progenitor cells by binding to and repressing the expression of differentiation genes with increased binding leading to further transcriptional silencing. Thus, the levels of SNAI2 binding to genomic targets determine the differentiation status of epithelial cells with increased levels triggering EMT and dedifferentiation, moderate (physiological) levels promoting epidermal progenitor function, and low levels leading to epidermal differentiation. PMID:25100569

  4. Transcriptional mechanisms link epithelial plasticity to adhesion and differentiation of epidermal progenitor cells

    PubMed Central

    Lee, Briana; Villarreal-Ponce, Alvaro; Fallahi, Magid; Ovadia, Jeremy; Sun, Peng; Yu, Qian-Chun; Ito, Seiji; Sinha, Satrajit; Nie, Qing; Dai, Xing

    2014-01-01

    During epithelial tissue morphogenesis, developmental progenitor cells undergo dynamic adhesive and cytoskeletal remodeling to trigger proliferation and migration. Transcriptional mechanisms that restrict such mild form of epithelial plasticity to maintain lineage-restricted differentiation in committed epithelial tissues are poorly understood. Here we report that simultaneous ablation of transcriptional repressor-encoding Ovol1 and Ovol2 results in expansion and blocked terminal differentiation of embryonic epidermal progenitor cells. Conversely, mice overexpressing Ovol2 in their skin epithelia exhibit precocious differentiation accompanied by smaller progenitor cell compartments. We show that Ovol1/2-deficient epidermal cells fail to undertake α-catenin–driven actin cytoskeletal reorganization and adhesive maturation, and exhibit changes that resemble epithelial-to-mesenchymal transition (EMT). Remarkably, these alterations as well as defective terminal differentiation are reversed upon depletion of EMT-promoting transcriptional factor Zeb1. Collectively, our findings reveal Ovol-Zeb1-α-catenin sequential repression and highlight functions of Ovol as gatekeepers of epithelial adhesion and differentiation by inhibiting progenitor-like traits and epithelial plasticity. PMID:24735878

  5. Short communication: Initial evidence supporting existence of potential rumen epidermal stem and progenitor cells.

    PubMed

    Yohe, T T; Tucker, H L M; Parsons, C L M; Geiger, A J; Akers, R M; Daniels, K M

    2016-09-01

    The bovine rumen epidermis is a keratinized multilayered tissue that experiences persistent cell turnover. Because of this constant cell turnover, epidermal stem cells and their slightly more differentiated daughter cells, epidermal progenitor cells, must exist in the stratum basale of rumen epidermis. To date, these 2 epidermal cell populations and any unique cellular markers they may possess remain completely uncharacterized in the bovine rumen. An important first step in this new research area is the demonstration of the relative abundance and existence of markers for these cells in rumen tissue. A related second step is to document rumen epidermal proliferative responses to an extrinsic signal such as nutrient concentration within the rumen. The objectives of this experiment were to evaluate the extrinsic effect of diet on (1) gene expression of 6 potential rumen epidermal stem or progenitor cell markers and (2) rumen epidermal cell proliferation within the stratum basale. Twelve preweaned Holstein heifers were fed either a restricted diet (R) or an enhanced diet (EH). Animals on R received a milk replacer (MR) diet fed at 0.44kg of powder dry matter (DM)/d (20.9% crude protein, 29.8% fat, DM basis) and EH received MR at 1.08kg of powder dry matter/d (28.9% crude protein, 26.2% fat, DM basis). All calves had access to a 20% crude protein starter and were weaned during wk 7 of the experiment. Lifetime DM intake was 0.73kg of DM/calf per day for R (5.88 Mcal of net energy/calf per day) and 1.26kg of DM/calf per day for EH (10.68 Mcal of net energy/calf per day). Twenty-four hours before slaughter heifers received an intravenous dose of 5-bromo-2'-deoxyuridine to label proliferating cells. Heifers were slaughtered at 8 wk of age, and rumen samples from the ventral sac region were obtained and stored in RNA preservative and processed for routine histology. Quantitative real-time reverse transcriptase PCR was used to analyze relative abundance of genes. Candidate

  6. Differentiation of ionic currents in CNS progenitor cells: dependence upon substrate attachment and epidermal growth factor.

    PubMed

    Feldman, D H; Thinschmidt, J S; Peel, A L; Papke, R L; Reier, P J

    1996-08-01

    Multipotential progenitor cells grown from central nervous system (CNS) tissues in defined media supplemented with epidermal growth factor (EGF), when attached to a suitable substratum, differentiate to express neural and glial histochemical markers and morphologies. To assess the functional characteristics of such cells, expression of voltage-gated Na+ and K+ currents (INa, IK) was studied by whole-cell patch clamp methods in progenitors raised from postnatal rat forebrain. Undifferentiated cells were acutely dissociated from proliferative "spheres," and differentiated cells were studied 1-25 days after plating spheres onto polylysine/laminin-treated coverslips. INa and IK were detected together in 58%, INa alone in 11%, and IK alone in 19% of differentiated cells recorded with K(+)-containing pipettes. With internal Cs+ (to isolate INa), INa up to 45 pA/pF was observed in some cells within 1 day after plating. I Na ranged up to 150 pA/pF subsequently. Overall, 84% of cells expressed I Na, with an average of 38 pA/pF. INa had fast kinetics, as in neurons, but steadystate inactivation curves were strongly negative, resembling those of glial INa. Inward tail currents sensitive to [K+]out were observed upon repolarization after the 10-ms test pulse with internal Cs+, indicating the expression of K+ channels in 82% of cells. In contrast to the substantial currents observed in differentiating cells, little or no INa or Ik-tail currents were detected in recordings from cells acutely dissociated from spheres. Thus, in the presence of EGF, ionic currents develop early during differentiation induced by attachment to an appropriate substratum. Cells switched from EGF to basic fibroblast growth factor (bFGF) when plated onto coverslips showed greatly reduced proliferation and developed less neuron-like morphologies than cells plated in the presence of EGF. INa was observed in only 53% of bFGF-treated cells, with an average of 9 pA/pF. Thus, in contrast to reports that b

  7. The carboxy-terminus of p63 links cell cycle control and the proliferative potential of epidermal progenitor cells

    PubMed Central

    Suzuki, Daisuke; Sahu, Raju; Leu, N. Adrian; Senoo, Makoto

    2015-01-01

    The transcription factor p63 (Trp63) plays a key role in homeostasis and regeneration of the skin. The p63 gene is transcribed from dual promoters, generating TAp63 isoforms with growth suppressive functions and dominant-negative ΔNp63 isoforms with opposing properties. p63 also encodes multiple carboxy (C)-terminal variants. Although mutations of C-terminal variants have been linked to the pathogenesis of p63-associated ectodermal disorders, the physiological role of the p63 C-terminus is poorly understood. We report here that deletion of the p63 C-terminus in mice leads to ectodermal malformation and hypoplasia, accompanied by a reduced proliferative capacity of epidermal progenitor cells. Notably, unlike the p63-null condition, we find that p63 C-terminus deficiency promotes expression of the cyclin-dependent kinase inhibitor p21Waf1/Cip1 (Cdkn1a), a factor associated with reduced proliferative capacity of both hematopoietic and neuronal stem cells. These data suggest that the p63 C-terminus plays a key role in the cell cycle progression required to maintain the proliferative potential of stem cells of many different lineages. Mechanistically, we show that loss of Cα, the predominant C-terminal p63 variant in epithelia, promotes the transcriptional activity of TAp63 and also impairs the dominant-negative activity of ΔNp63, thereby controlling p21Waf1/Cip1 expression. We propose that the p63 C-terminus links cell cycle control and the proliferative potential of epidermal progenitor cells via mechanisms that equilibrate TAp63 and ΔNp63 isoform function. PMID:25503409

  8. Hdac1 and Hdac2 act redundantly to control p63 and p53 functions in epidermal progenitor cells

    PubMed Central

    LeBoeuf, Matthew; Terrell, Anne; Trivedi, Sohum; Sinha, Satrajit; Epstein, Jonathan A.; Olson, Eric N.; Morrisey, Edward E.; Millar, Sarah E.

    2010-01-01

    Summary Epidermal and hair follicle development from surface ectodermal progenitor cells require coordinated changes in gene expression. Histone deacetylases alter gene expression programs through modification of chromatin and transcription factors. We find that deletion of ectodermal Hdac1 and Hdac2 results in dramatic failure of hair follicle specification and epidermal proliferation and stratification, phenocopying loss of the key ectodermal transcription factor p63. While expression of p63 and its positively regulated basal cell targets is maintained in Hdac1/2 deficient ectoderm, targets of p63-mediated repression, including p21, 14-3-3σ and p16/INK4a, are ectopically expressed, and HDACs bind and are active at their promoter regions in normal undifferentiated keratinocytes. Mutant embryos display increased levels of acetylated p53, which opposes p63 functions, and p53 is required for HDAC inhibitor-mediated p21 expression in keratinocytes. Our data identify critical requirements for HDAC1/2 in epidermal development, and indicate that HDAC1/2 directly mediate repressive functions of p63, and suppress p53 activity. PMID:21093383

  9. Forward genetics identifies Kdf1/1810019J16Rik as an essential regulator of the proliferation-differentiation decision in epidermal progenitor cells

    PubMed Central

    Lee, Sunjin; Kong, Yong; Weatherbee, Scott D.

    2013-01-01

    Cell fate decisions during embryogenesis and adult life govern tissue formation, homeostasis and repair. Two key decisions that must be tightly coordinated are proliferation and differentiation. Overproliferation can lead to hyperplasia or tumor formation while premature differentiation can result in a depletion of proliferating cells and organ failure. Maintaining this balance is especially important in tissues that undergo rapid turnover like skin however, despite recent advances, the genetic mechanisms that balance cell differentiation and proliferation are still unclear. In an unbiased genetic screen to identify genes affecting early development, we identified an essential regulator of the proliferation-differentiation balance in epidermal progenitor cells, the Keratinocyte differentiation factor 1 (Kdf1; 1810019J16Rik) gene. Kdf1 is expressed in epidermal cells from early stages of epidermis formation through adulthood. Specifically, Kdf1 is expressed both in epidermal progenitor cells where it acts to curb the rate of proliferation as well as in their progeny where it is required to block proliferation and promote differentiation. Consequently, Kdf1 mutants display both uncontrolled cell proliferation in the epidermis and failure to develop terminal fates. Our findings reveal a dual role for the novel gene Kdf1 both as a repressive signal for progenitor cell proliferation through its inhibition of p63 and a strong inductive signal for terminal differentiation through its interaction with the cell cycle regulator Stratifin. PMID:24075906

  10. Requirement for neurogenesis to proceed through the division of neuronal progenitors following differentiation of epidermal growth factor and fibroblast growth factor-2-responsive human neural stem cells.

    PubMed

    Ostenfeld, Thor; Svendsen, Clive N

    2004-01-01

    Epidermal growth factor (EGF)- and fibroblast growth factor-2 (FGF-2)-responsive human neural stem cells may provide insight into mechanisms of neural development and have applications in cell-based therapeutics for neurological disease. However, their biology after expansion in vitro is currently poorly understood. Cells grown in either EGF or FGF-2 or a combination of both mitogens displayed characteristically similar levels of transcriptional activation and comparable proliferative profiles with linear cell-cycle kinetics and possessed similar neuronal differentiation capabilities. These data support the view that human neurospheres at later stages of expansion (>10 weeks) are comprised overwhelmingly of a single type of stem cell responsive to both EGF and FGF-2. After mitogen withdrawal and neurosphere plating, bromodeoxyuridine pulse-chase experiments revealed that the stem cells did not undergo differentiation directly into neurons. Instead, most immature neurons arose via the division of emerging progenitor cells in the absence of exogenous EGF or FGF-2. Neurogenesis was abolished by application of high concentrations of either EGF/FGF-2 or the mitotic inhibitor cytosine-b-arabinofuranoside, suggesting that there is an obligatory requirement for at least one round of cell division in the absence of mitogens as a prelude to terminal neuronal differentiation. The differentiation of human neurospheres provides a useful model of human neurogenesis, and the data presented indicate that it proceeds through the division of committed neuronal progenitor cells rather than directly from the neural stem cell. PMID:15342944

  11. 25 YEARS OF EPIDERMAL STEM CELLS

    PubMed Central

    Ghadially, Ruby

    2012-01-01

    This is a chronicle of concepts in the field of epidermal stem cell biology and a historic look at their development over time. The last 25 years have seen the evolution of epidermal stem cell science, from first fundamental studies to a sophisticated science. The study of epithelial stem cell biology was aided by the ability to visualize the distribution of stem cells and their progeny through lineage analysis studies. The excellent progress we have made in understanding epidermal stem cell biology is discussed in this article. The challenges we still face in understanding epidermal stem cell include defining molecular markers for stem and progenitor subpopulations, determining the locations and contributions of the different stem cell niches, and mapping regulatory pathways of epidermal stem cell proliferation and differentiation. However, our rapidly evolving understanding of epidermal stem cells has many potential uses that promise to translate into improved patient therapy. PMID:22205306

  12. Hinokitiol inhibits vasculogenic mimicry activity of breast cancer stem/progenitor cells through proteasome-mediated degradation of epidermal growth factor receptor

    PubMed Central

    TU, DOM-GENE; YU, YUN; LEE, CHE-HSIN; KUO, YU-LIANG; LU, YIN-CHE; TU, CHI-WEN; CHANG, WEN-WEI

    2016-01-01

    Hinokitiol, alternatively known as β-thujaplicin, is a tropolone-associated natural compound with antimicrobial, anti-inflammatory and antitumor activity. Breast cancer stem/progenitor cells (BCSCs) are a subpopulation of breast cancer cells associated with tumor initiation, chemoresistance and metastatic behavior, and may be enriched by mammosphere cultivation. Previous studies have demonstrated that BCSCs exhibit vasculogenic mimicry (VM) activity via the epidermal growth factor receptor (EGFR) signaling pathway. The present study investigated the anti-VM activity of hinokitiol in BCSCs. At a concentration below the half maximal inhibitory concentration, hinokitiol inhibited VM formation of mammosphere cells derived from two human breast cancer cell lines. Hinokitiol was additionally indicated to downregulate EGFR protein expression in mammosphere-forming BCSCs without affecting the expression of messenger RNA. The protein stability of EGFR in BCSCs was also decreased by hinokitiol. The EGFR protein expression and VM formation capability of hinokitiol-treated BCSCs were restored by co-treatment with MG132, a proteasome inhibitor. In conclusion, the present study indicated that hinokitiol may inhibit the VM activity of BCSCs through stimulating proteasome-mediated EGFR degradation. Hinokitiol may act as an anti-VM agent, and may be useful for the development of novel breast cancer therapeutic agents. PMID:27073579

  13. GRHL3/GET1 and Trithorax Group Members Collaborate to Activate the Epidermal Progenitor Differentiation Program

    PubMed Central

    Hopkin, Amelia Soto; Gordon, William; Klein, Rachel Herndon; Espitia, Francisco; Daily, Kenneth; Zeller, Michael; Baldi, Pierre; Andersen, Bogi

    2012-01-01

    The antagonistic actions of Polycomb and Trithorax are responsible for proper cell fate determination in mammalian tissues. In the epidermis, a self-renewing epithelium, previous work has shown that release from Polycomb repression only partially explains differentiation gene activation. We now show that Trithorax is also a key regulator of epidermal differentiation, not only through activation of genes repressed by Polycomb in progenitor cells, but also through activation of genes independent of regulation by Polycomb. The differentiation associated transcription factor GRHL3/GET1 recruits the ubiquitously expressed Trithorax complex to a subset of differentiation genes. PMID:22829784

  14. The Enhancer of Split Complex and Adjacent Genes in the 96f Region of Drosophila Melanogaster Are Required for Segregation of Neural and Epidermal Progenitor Cells

    PubMed Central

    Schrons, H.; Knust, E.; Campos-Ortega, J. A.

    1992-01-01

    The Enhancer of split complex [E(spl)-C] of Drosophila melanogaster is located in the 96F region of the third chromosome and comprises at least seven structurally related genes, HLH-mδ, HLH-mγ, HLH-mβ, HLH-m3, HLH-m5, HLH-m7 and E(spl). The functions of these genes are required during early neurogenesis to give neuroectodermal cells access to the epidermal pathway of development. Another gene in the 96F region, namely groucho, is also required for this process. However, groucho is not structurally related to, and appears to act independently of, the genes of the E(spl)-C; the possibility is discussed that groucho acts upstream to the E(spl)-C genes. Indirect evidence suggests that a neighboring transcription unit (m4) may also take part in the process. Of all these genes, only gro is essential; m4 is a dispensable gene, the deletion of which does not produce detectable morphogenetic abnormalities, and the genes of the E(spl)-C are to some extent redundant and can partially substitute for each other. This redundancy is probably due to the fact that the seven genes of the E(spl)-C encode highly conserved putative DNA-binding proteins of the bHLH family. The genes of the complex are interspersed among other genes which appear to be unrelated to the neuroepidermal lineage dichotomy. PMID:1427039

  15. Epidermal Stem Cells in Orthopaedic Regenerative Medicine

    PubMed Central

    Li, Jin; Zhen, Gehua; Tsai, Shin-Yi; Jia, Xiaofeng

    2013-01-01

    In the last decade, great advances have been made in epidermal stem cell studies at the cellular and molecular level. These studies reported various subpopulations and differentiations existing in the epidermal stem cell. Although controversies and unknown issues remain, epidermal stem cells possess an immune-privileged property in transplantation together with easy accessibility, which is favorable for future clinical application. In this review, we will summarize the biological characteristics of epidermal stem cells, and their potential in orthopedic regenerative medicine. Epidermal stem cells play a critical role via cell replacement, and demonstrate significant translational potential in the treatment of orthopedic injuries and diseases, including treatment for wound healing, peripheral nerve and spinal cord injury, and even muscle and bone remodeling. PMID:23727934

  16. Mechanotransduction in epidermal Merkel cells

    PubMed Central

    Nakatani, Masashi; Maksimovic, Srdjan; Baba, Yoshichika; Lumpkin, Ellen A.

    2014-01-01

    The cellular and molecular basis of vertebrate touch reception remains least understood among the traditional five senses. Somatosensory afferents that innervate the skin encode distinct tactile qualities, such as flutter, slip and pressure. Gentle touch is thought to be transduced by somatosensory afferents whose tactile end organs selectively filter mechanical stimuli. These tactile end organs comprise afferent terminals in association with non-neuronal cell types such as Merkel cells, keratinocytes and Schwann cells. An open question is whether these non-neuronal cells serve primarily as passive mechanical filters or whether they actively participate in mechanosensory transduction. This question has been most extensively studied in Merkel cells, which are epidermal cells that complex with sensory afferents in regions of high tactile acuity such as fingertips, whisker follicles, and touch domes. Merkel cell-neurite complexes mediate slowly adapting type I (SAI) responses, which encode sustained pressure and represent object features with high fidelity. How Merkel cells contribute to unique SAI firing patterns has been debated for decades; however, three recent studies in rodent models provide some direct answers. First, whole-cell recordings demonstrate that Merkel cells are touch-sensitive cells with fast, mechanically activated currents that require Piezo2. Second, optogenetics and intact recordings show that Merkel cells mediate sustained SAI firing. Finally, loss-of-function studies in transgenic mouse models reveal that SAI afferents are also touch sensitive. Together, these studies identify molecular mechanisms of mechanotransduction in Merkel cells, reveal unexpected functions for these cells in touch and support a revised, two-receptor site model of mechanosensory transduction. PMID:25053537

  17. Progenitor Cells and Podocyte Regeneration

    PubMed Central

    Shankland, Stuart J.; Pippin, Jeffrey W.; Duffield, Jeremy S.

    2014-01-01

    The very limited ability of adult podocytes to proliferate in vivo is clinically significant because: podocytes form a vascular barrier which is functionally critical to the nephron; podocyte hypoplasia is a characteristic of disease; and inadequate regeneration of podocytes is a major cause of persistent podocyte hypoplasia. Excessive podocyte loss or inadequate replacement leads to glomerulosclerosis in many progressive kidney diseases. Thus, restoration of podocyte cell density is almost certainly reliant on regeneration by podocyte progenitors. However such putative progenitors have remained elusive until recently. In this review we describe the developmental processes leading to podocyte and parietal epithelial cell (PEC) formation during glomerulogenesis. We compare evidence that in normal human kidneys PECs expressing ‘progenitor’ markers CD133 and CD24 can differentiate into podocytes in vitro and in vivo with evidence from animal models suggesting a more limited role of PEC-capacity to serve as podocyte progenitors in adults. We will highlight tantalizing new evidence that specialized vascular wall cells of afferent arterioles including those which produce renin in healthy kidney, provide a novel local progenitor source of new PECs and podocytes in response to podocyte hypoplasia in the adult, and draw comparisons with glomerulogenesis. PMID:25217270

  18. Endothelial progenitor cells: identity defined?

    PubMed Central

    Timmermans, Frank; Plum, Jean; Yöder, Mervin C; Ingram, David A; Vandekerckhove, Bart; Case, Jamie

    2009-01-01

    Abstract In the past decade, researchers have gained important insights on the role of bone marrow (BM)-derived cells in adult neovascularization. A subset of BM-derived cells, called endothelial progenitor cells (EPCs), has been of particular interest, as these cells were suggested to home to sites of neovascularization and neoendothelialization and differentiate into endothelial cells (ECs) in situ, a process referred to as postnatal vasculogenesis. Therefore, EPCs were proposed as a potential regenerative tool for treating human vascular disease and a possible target to restrict vessel growth in tumour pathology. However, conflicting results have been reported in the field, and the identification, characterization, and exact role of EPCs in vascular biology is still a subject of much discussion. The focus of this review is on the controversial issues in the field of EPCs which are related to the lack of a unique EPC marker, identification challenges related to the paucity of EPCs in the circulation, and the important phenotypical and functional overlap between EPCs, haematopoietic cells and mature ECs. We also discuss our recent findings on the origin of endothelial outgrowth cells (EOCs), showing that this in vitro defined EC population does not originate from circulating CD133+ cells or CD45+ haematopoietic cells. PMID:19067770

  19. Progenitor cells in the adult pancreas.

    PubMed

    Holland, Andrew M; Góñez, L Jorge; Harrison, Leonard C

    2004-01-01

    The beta-cell mass in the adult pancreas possesses the ability to undergo limited regeneration following injury. Identifying the progenitor cells involved in this process and understanding the mechanisms leading to their maturation will open new avenues for the treatment of type 1 diabetes. However, despite steady advances in determining the molecular basis of early pancreatic development, the identification of pancreatic stem cells or beta-cell progenitors and the molecular mechanisms underlying beta-cell regeneration remain unclear. Recent advances in the directed differentiation of embryonic and adult stem cells has heightened interest in the possible application of stem cell therapy in the treatment of type 1 diabetes. Drawing on the expanding knowledge of pancreas development, beta-cell regeneration and stem cell research, this review focuses on progenitor cells in the adult pancreas as a potential source of beta-cells. PMID:14737742

  20. Cell motion predicts human epidermal stemness

    PubMed Central

    Toki, Fujio; Tate, Sota; Imai, Matome; Matsushita, Natsuki; Shiraishi, Ken; Sayama, Koji; Toki, Hiroshi; Higashiyama, Shigeki

    2015-01-01

    Image-based identification of cultured stem cells and noninvasive evaluation of their proliferative capacity advance cell therapy and stem cell research. Here we demonstrate that human keratinocyte stem cells can be identified in situ by analyzing cell motion during their cultivation. Modeling experiments suggested that the clonal type of cultured human clonogenic keratinocytes can be efficiently determined by analysis of early cell movement. Image analysis experiments demonstrated that keratinocyte stem cells indeed display a unique rotational movement that can be identified as early as the two-cell stage colony. We also demonstrate that α6 integrin is required for both rotational and collective cell motion. Our experiments provide, for the first time, strong evidence that cell motion and epidermal stemness are linked. We conclude that early identification of human keratinocyte stem cells by image analysis of cell movement is a valid parameter for quality control of cultured keratinocytes for transplantation. PMID:25897083

  1. Tethering of Epidermal Growth Factor (EGF) to Beta Tricalcium Phosphate (βTCP) via Fusion to a High Affinity, Multimeric βTCP-Binding Peptide: Effects on Human Multipotent Stromal Cells/Connective Tissue Progenitors

    PubMed Central

    Stockdale, Linda; Saini, Sunil; Lee, Richard T.; Griffith, Linda G.

    2015-01-01

    Transplantation of freshly-aspirated autologous bone marrow, together with a scaffold, is a promising clinical alternative to harvest and transplantation of autologous bone for treatment of large defects. However, survival proliferation, and osteogenic differentiation of the marrow-resident stem and progenitor cells with osteogenic potential can be limited in large defects by the inflammatory microenvironment. Previous studies using EGF tethered to synthetic polymer substrates have demonstrated that surface-tethered EGF can protect human bone marrow-derived osteogenic stem and progenitor cells from pro-death inflammatory cues and enhance their proliferation without detriment to subsequent osteogenic differentiation. The objective of this study was to identify a facile means of tethering EGF to clinically-relevant βTCP scaffolds and to demonstrate the bioactivity of EGF tethered to βTCP using stimulation of the proliferative response of human bone-marrow derived mesenchymal stem cells (hBMSC) as a phenotypic metric. We used a phage display library and panned against βTCP and composites of βTCP with a degradable polyester biomaterial, together with orthogonal blocking schemes, to identify a 12-amino acid consensus binding peptide sequence, LLADTTHHRPWT, with high affinity for βTCP. When a single copy of this βTCP-binding peptide sequence was fused to EGF via a flexible peptide tether domain and expressed recombinantly in E. coli together with a maltose-binding domain to aid purification, the resulting fusion protein exhibited modest affinity for βTCP. However, a fusion protein containing a linear concatamer containing 10 repeats of the binding motif the resulting fusion protein showed high affinity stable binding to βTCP, with only 25% of the protein released after 7 days at 37oC. The fusion protein was bioactive, as assessed by its abilities to activate kinase signaling pathways downstream of the EGF receptor when presented in soluble form, and to enhance

  2. Isolation, characterization, and differentiation of progenitor cells from human adult adrenal medulla.

    PubMed

    Santana, Magda M; Chung, Kuei-Fang; Vukicevic, Vladimir; Rosmaninho-Salgado, Joana; Kanczkowski, Waldemar; Cortez, Vera; Hackmann, Klaus; Bastos, Carlos A; Mota, Alfredo; Schrock, Evelin; Bornstein, Stefan R; Cavadas, Cláudia; Ehrhart-Bornstein, Monika

    2012-11-01

    Chromaffin cells, sympathetic neurons of the dorsal ganglia, and the intermediate small intensely fluorescent cells derive from a common neural crest progenitor cell. Contrary to the closely related sympathetic nervous system, within the adult adrenal medulla a subpopulation of undifferentiated progenitor cells persists, and recently, we established a method to isolate and differentiate these progenitor cells from adult bovine adrenals. However, no studies have elucidated the existence of adrenal progenitor cells within the human adrenal medulla. Here we describe the isolation, characterization, and differentiation of chromaffin progenitor cells obtained from adult human adrenals. Human chromaffin progenitor cells were cultured in low-attachment conditions for 10-12 days as free-floating spheres in the presence of fibroblast growth factor-2 (FGF-2) and epidermal growth factor. These primary human chromosphere cultures were characterized by the expression of several progenitor markers, including nestin, CD133, Notch1, nerve growth factor receptor, Snai2, Sox9, Sox10, Phox2b, and Ascl1 on the molecular level and of Sox9 on the immunohistochemical level. In opposition, phenylethanolamine N-methyltransferase (PNMT), a marker for differentiated chromaffin cells, significantly decreased after 12 days in culture. Moreover, when plated on poly-l-lysine/laminin-coated slides in the presence of FGF-2, human chromaffin progenitor cells were able to differentiate into two distinct neuron-like cell types, tyrosine hydroxylase (TH)(+)/β-3-tubulin(+) cells and TH(-)/β-3-tubulin(+) cells, and into chromaffin cells (TH(+)/PNMT(+)). This study demonstrates the presence of progenitor cells in the human adrenal medulla and reveals their potential use in regenerative medicine, especially in the treatment of neuroendocrine and neurodegenerative diseases. PMID:23197690

  3. Isolation, Characterization, and Differentiation of Progenitor Cells from Human Adult Adrenal Medulla

    PubMed Central

    Santana, Magda M.; Chung, Kuei-Fang; Vukicevic, Vladimir; Rosmaninho-Salgado, Joana; Kanczkowski, Waldemar; Cortez, Vera; Hackmann, Karl; Bastos, Carlos A.; Mota, Alfredo; Schrock, Evelin; Bornstein, Stefan R.; Cavadas, Cláudia

    2012-01-01

    Chromaffin cells, sympathetic neurons of the dorsal ganglia, and the intermediate small intensely fluorescent cells derive from a common neural crest progenitor cell. Contrary to the closely related sympathetic nervous system, within the adult adrenal medulla a subpopulation of undifferentiated progenitor cells persists, and recently, we established a method to isolate and differentiate these progenitor cells from adult bovine adrenals. However, no studies have elucidated the existence of adrenal progenitor cells within the human adrenal medulla. Here we describe the isolation, characterization, and differentiation of chromaffin progenitor cells obtained from adult human adrenals. Human chromaffin progenitor cells were cultured in low-attachment conditions for 10–12 days as free-floating spheres in the presence of fibroblast growth factor-2 (FGF-2) and epidermal growth factor. These primary human chromosphere cultures were characterized by the expression of several progenitor markers, including nestin, CD133, Notch1, nerve growth factor receptor, Snai2, Sox9, Sox10, Phox2b, and Ascl1 on the molecular level and of Sox9 on the immunohistochemical level. In opposition, phenylethanolamine N-methyltransferase (PNMT), a marker for differentiated chromaffin cells, significantly decreased after 12 days in culture. Moreover, when plated on poly-l-lysine/laminin-coated slides in the presence of FGF-2, human chromaffin progenitor cells were able to differentiate into two distinct neuron-like cell types, tyrosine hydroxylase (TH)+/β-3-tubulin+ cells and TH−/β-3-tubulin+ cells, and into chromaffin cells (TH+/PNMT+). This study demonstrates the presence of progenitor cells in the human adrenal medulla and reveals their potential use in regenerative medicine, especially in the treatment of neuroendocrine and neurodegenerative diseases. PMID:23197690

  4. Cell culture: Progenitor cells from human brain after death

    NASA Astrophysics Data System (ADS)

    Palmer, Theo D.; Schwartz, Philip H.; Taupin, Philippe; Kaspar, Brian; Stein, Stuart A.; Gage, Fred H.

    2001-05-01

    Culturing neural progenitor cells from the adult rodent brain has become routine and is also possible from human fetal tissue, but expansion of these cells from postnatal and adult human tissue, although preferred for ethical reasons, has encountered problems. Here we describe the isolation and successful propagation of neural progenitor cells from human postmortem tissues and surgical specimens. Although the relative therapeutic merits of adult and fetal progenitor cells still need to be assessed, our results may extend the application of these progenitor cells in the treatment of neurodegenerative diseases.

  5. [Biology of epidermal stem cells: impact on medicine].

    PubMed

    Pikuła, Michał; Trzonkowski, Piotr

    2009-01-01

    The epidermis is a self-renewing tissue which regenerates constantly. It consists mainly of keratinocytes of various degree of differentiation, from the proliferative basal layer to the terminally differentiated horny layer. Keratinocytes are specialized cells responsible for cohesion, barrier functions, and immunological reactions. The maintenance of homeostasis in the epidermis is possible via the self-renewing ability of the epidermal stem-cell population, which gives rise to differentiated keratinocytes. It is believed that epidermal stem cells play an important role in cellular regeneration, wound healing, and the pathogenesis of skin cancers. Epidermal stem cells reside in the basal layer of the epidermis, the bulge region of the hair follicle, and the germinal hair follicle matrix. Epidermal stem cells are relatively quiescent, slow-cycling cells defined by their great proliferative potential and unlimited capacity for self-renewal. Adult human epidermal stem cells can be activated and expanded in vitro under appropriate conditions. Cultured human keratinocytes and epidermal stem cells may be then transplanted as a biological dressing in burn injuries, chronic wounds, and various skin diseases. Additionally, epidermal stem cells have become a target for gene therapy and drug testing. In this review the fundamental characteristics of epidermal stem cells and the signaling pathways involved in the regulation of their proliferation and differentiation are discussed. The possibilities of using epidermal stem cells in medicine are also presented. PMID:19837987

  6. Human Liver Progenitor Cells for Liver Repair

    PubMed Central

    Lombard, Catherine A.; Prigent, Julie; Sokal, Etienne M.

    2013-01-01

    Because of their high proliferative capacity, resistance to cryopreservation, and ability to differentiate into hepatocyte-like cells, stem and progenitor cells have recently emerged as attractive cell sources for liver cell therapy, a technique used as an alternative to orthotopic liver transplantation in the treatment of various hepatic ailments ranging from metabolic disorders to end-stage liver disease. Although stem and progenitor cells have been isolated from various tissues, obtaining them from the liver could be an advantage for the treatment of hepatic disorders. However, the techniques available to isolate these stem/progenitor cells are numerous and give rise to cell populations with different morphological and functional characteristics. In addition, there is currently no established consensus on the tests that need to be performed to ensure the quality and safety of these cells when used clinically. The purpose of this review is to describe the different types of liver stem/progenitor cells currently reported in the literature, discuss their suitability and limitations in terms of clinical applications, and examine how the culture and transplantation techniques can potentially be improved to achieve a better clinical outcome. PMID:26858860

  7. In vivo identification of periodontal progenitor cells.

    PubMed

    Roguljic, H; Matthews, B G; Yang, W; Cvija, H; Mina, M; Kalajzic, I

    2013-08-01

    The periodontal ligament contains progenitor cells; however, their identity and differentiation potential in vivo remain poorly characterized. Previous results have suggested that periodontal tissue progenitors reside in perivascular areas. Therefore, we utilized a lineage-tracing approach to identify and track periodontal progenitor cells from the perivascular region in vivo. We used an alpha-smooth muscle actin (αSMA) promoter-driven and tamoxifen-inducible Cre system (αSMACreERT2) that, in combination with a reporter mouse line (Ai9), permanently labels a cell population, termed 'SMA9'. To trace the differentiation of SMA9-labeled cells into osteoblasts/cementoblasts, we utilized a Col2.3GFP transgene, while expression of Scleraxis-GFP was used to follow differentiation into periodontal ligament fibroblasts during normal tissue formation and remodeling following injury. In uninjured three-week-old SMA9 mice, tamoxifen labeled a small population of cells in the periodontal ligament that expanded over time, particularly in the apical region of the root. By 17 days and 7 weeks after labeling, some SMA9-labeled cells expressed markers indicating differentiation into mature lineages, including cementocytes. Following injury, SMA9 cells expanded, and differentiated into cementoblasts, osteoblasts, and periodontal ligament fibroblasts. SMA9-labeled cells represent a source of progenitors that can give rise to mature osteoblasts, cementoblasts, and fibroblasts within the periodontium. PMID:23735585

  8. Hypoxia affects in vitro proliferation and differentiation of mouse corneal epithelial progenitor cell.

    PubMed

    Dong, Nuo; Qin, Wenjuan; Xue, Yuhua; Li, Cheng; Liu, Zuguo

    2013-08-01

    This study was to investigate the proliferation and differentiation of mouse corneal epithelial progenitor cell in hypoxic airlift culture. Mouse corneal epithelial progenitor cell line progenitor cells were cultured under airlift with normoxic and hypoxic conditions for various durations up to 2 wk. Under normoxic conditions when exposed to air, the hyperproliferation and abnormal epidermal-like differentiation of mouse corneal epithelium was induced, whereas when exposed to air under hypoxic conditions, although we observed augmented proliferation, the abnormal differentiation was inhibited. The mechanism by which hypoxia prevents abnormal differentiation may involve downregulation of Wnt signaling pathways, which were inhibited in cells cultured with hypoxic airlift technique. In conclusion, hypoxia can prevent abnormal differentiation while enhancing the proliferation of corneal epithelial cells by blocking Wnt/β-catenin signaling pathway. PMID:23739874

  9. Progenitor cells for ocular surface regenerative therapy.

    PubMed

    Casaroli-Marano, Ricardo P; Nieto-Nicolau, Nuria; Martínez-Conesa, Eva M

    2013-01-01

    The integrity and normal function of the corneal epithelium are essential for maintaining the cornea's transparency and vision. The existence of a cell population with progenitor characteristics in the limbus maintains a dynamic of constant epithelial repair and renewal. Currently, cell-based therapies for bio-replacement, such as cultured limbal epithelial transplantation and cultured oral mucosal epithelial transplantation, present very encouraging clinical results for treating limbal stem cell deficiencies. Another emerging therapeutic strategy consists of obtaining and implementing human progenitor cells of different origins using tissue engineering methods. The development of cell-based therapies using stem cells, such as human adult mesenchymal stromal cells, represents a significant breakthrough in the treatment of certain eye diseases and also offers a more rational, less invasive and more physiological approach to ocular surface regeneration. PMID:23257987

  10. Noninvasive Imaging of Administered Progenitor Cells

    SciTech Connect

    Steven R Bergmann, M.D., Ph.D.

    2012-12-03

    The objective of this research grant was to develop an approach for labeling progenitor cells, specifically those that we had identified as being able to replace ischemic heart cells, so that the distribution could be followed non-invasively. In addition, the research was aimed at determining whether administration of progenitor cells resulted in improved myocardial perfusion and function. The efficiency and toxicity of radiolabeling of progenitor cells was to be evaluated. For the proposed clinical protocol, subjects with end-stage ischemic coronary artery disease were to undergo a screening cardiac positron emission tomography (PET) scan using N-13 ammonia to delineate myocardial perfusion and function. If they qualified based on their PET scan, they would undergo an in-hospital protocol whereby CD34+ cells were stimulated by the administration of granulocytes-colony stimulating factor (G-CSF). CD34+ cells would then be isolated by apharesis, and labeled with indium-111 oxine. Cells were to be re-infused and subjects were to undergo single photon emission computed tomography (SPECT) scanning to evaluate uptake and distribution of labeled progenitor cells. Three months after administration of progenitor cells, a cardiac PET scan was to be repeated to evaluate changes in myocardial perfusion and/or function. Indium oxine is a radiopharmaceutical for labeling of autologous lymphocytes. Indium-111 (In-111) decays by electron capture with a t{sub ½} of 67.2 hours (2.8 days). Indium forms a saturated complex that is neutral, lipid soluble, and permeates the cell membrane. Within the cell, the indium-oxyquinolone complex labels via indium intracellular chelation. Following leukocyte labeling, ~77% of the In-111 is incorporated in the cell pellet. The presence of red cells and /or plasma reduces the labeling efficacy. Therefore, the product needed to be washed to eliminate plasma proteins. This repeated washing can damage cells. The CD34 selected product was a 90

  11. Cardiac progenitor cells for heart repair

    PubMed Central

    Le, TYL; Chong, JJH

    2016-01-01

    Stem cell therapy is being investigated as an innovative and promising strategy to restore cardiac function in patients with heart failure. Several stem cell populations, including adult (multipotent) stem cells from developed organs and tissues, have been tested for cardiac repair with encouraging clinical and pre-clinical results. The heart has been traditionally considered a post-mitotic organ, however, this view has recently changed with the identification of stem/progenitor cells residing within the adult heart. Given their cardiac developmental origins, these endogenous cardiac progenitor cells (CPCs) may represent better candidates for cardiac cell therapy compared with stem cells from other organs such as the bone marrow and adipose tissue. This brief review will outline current research into CPC populations and their cardiac repair/regenerative potential. PMID:27551540

  12. Metabolic profiling of Arabidopsis thaliana epidermal cells

    PubMed Central

    Ebert, Berit; Zöller, Daniela; Erban, Alexander; Fehrle, Ines; Hartmann, Jürgen; Niehl, Annette; Kopka, Joachim; Fisahn, Joachim

    2010-01-01

    Metabolic phenotyping at cellular resolution may be considered one of the challenges in current plant physiology. A method is described which enables the cell type-specific metabolic analysis of epidermal cell types in Arabidopsis thaliana pavement, basal, and trichome cells. To achieve the required high spatial resolution, single cell sampling using microcapillaries was combined with routine gas chromatography-time of flight-mass spectrometry (GC-TOF-MS) based metabolite profiling. The identification and relative quantification of 117 mostly primary metabolites has been demonstrated. The majority, namely 90 compounds, were accessible without analytical background correction. Analyses were performed using cell type-specific pools of 200 microsampled individual cells. Moreover, among these identified metabolites, 38 exhibited differential pool sizes in trichomes, basal or pavement cells. The application of an independent component analysis confirmed the cell type-specific metabolic phenotypes. Significant pool size changes between individual cells were detectable within several classes of metabolites, namely amino acids, fatty acids and alcohols, alkanes, lipids, N-compounds, organic acids and polyhydroxy acids, polyols, sugars, sugar conjugates and phenylpropanoids. It is demonstrated here that the combination of microsampling and GC-MS based metabolite profiling provides a method to investigate the cellular metabolism of fully differentiated plant cell types in vivo. PMID:20150518

  13. Pigment Cell Progenitors in Zebrafish Remain Multipotent through Metamorphosis.

    PubMed

    Singh, Ajeet Pratap; Dinwiddie, April; Mahalwar, Prateek; Schach, Ursula; Linker, Claudia; Irion, Uwe; Nüsslein-Volhard, Christiane

    2016-08-01

    The neural crest is a transient, multipotent embryonic cell population in vertebrates giving rise to diverse cell types in adults via intermediate progenitors. The in vivo cell-fate potential and lineage segregation of these postembryonic progenitors is poorly understood, and it is unknown if and when the progenitors become fate restricted. We investigate the fate restriction in the neural crest-derived stem cells and intermediate progenitors in zebrafish, which give rise to three distinct adult pigment cell types: melanophores, iridophores, and xanthophores. By inducing clones in sox10-expressing cells, we trace and quantitatively compare the pigment cell progenitors at four stages, from embryogenesis to metamorphosis. At all stages, a large fraction of the progenitors are multipotent. These multipotent progenitors have a high proliferation ability, which diminishes with fate restriction. We suggest that multipotency of the nerve-associated progenitors lasting into metamorphosis may have facilitated the evolution of adult-specific traits in vertebrates. PMID:27453500

  14. Chondrogenic Progenitor Cells Respond to Cartilage Injury

    PubMed Central

    Choe, Hyeonghun; Zheng, Hongjun; Yu, Yin; Jang, Keewoong; Walter, Morgan W.; Lehman, Abigail D.; Ding, Lei; Buckwalter, Joseph A.; Martin, James A.

    2014-01-01

    Objective Hypocellularity resulting from chondrocyte death in the aftermath of mechanical injury is thought to contribute to posttraumatic osteoarthritis. However, we observed that nonviable areas in cartilage injured by blunt impact were repopulated within 7–14 days by cells that appeared to migrate from the surrounding matrix. The aim of this study was to assess our hypothesis that the migrating cell population included chondrogenic progenitor cells that were drawn to injured cartilage by alarmins. Methods Osteochondral explants obtained from mature cattle were injured by blunt impact or scratching, resulting in localized chondrocyte death. Injured sites were serially imaged by confocal microscopy, and migrating cells were evaluated for chondrogenic progenitor characteristics. Chemotaxis assays were used to measure the responses to chemokines, injury-conditioned medium, dead cell debris, and high mobility group box chromosomal protein 1 (HMGB-1). Results Migrating cells were highly clonogenic and multipotent and expressed markers associated with chondrogenic progenitor cells. Compared with chondrocytes, these cells overexpressed genes involved in proliferation and migration and underexpressed cartilage matrix genes. They were more active than chondrocytes in chemotaxis assays and responded to cell lysates, conditioned medium, and HMGB-1. Glycyrrhizin, a chelator of HMGB-1 and a blocking antibody to receptor for advanced glycation end products (RAGE), inhibited responses to cell debris and conditioned medium and reduced the numbers of migrating cells on injured explants. Conclusion Injuries that caused chondrocyte death stimulated the emergence and homing of chondrogenic progenitor cells, in part via HMGB-1 release and RAGE-mediated chemotaxis. Their repopulation of the matrix could promote the repair of chondral damage that might otherwise contribute to progressive cartilage loss. PMID:22777600

  15. Human progenitor cells for bone engineering applications.

    PubMed

    de Peppo, G M; Thomsen, P; Karlsson, C; Strehl, R; Lindahl, A; Hyllner, J

    2013-06-01

    In this report, the authors review the human skeleton and the increasing burden of bone deficiencies, the limitations encountered with the current treatments and the opportunities provided by the emerging field of cell-based bone engineering. Special emphasis is placed on different sources of human progenitor cells, as well as their pros and cons in relation to their utilization for the large-scale construction of functional bone-engineered substitutes for clinical applications. It is concluded that, human pluripotent stem cells represent a valuable source for the derivation of progenitor cells, which combine the advantages of both embryonic and adult stem cells, and indeed display high potential for the construction of functional substitutes for bone replacement therapies. PMID:23642054

  16. Endothelial progenitor cells in hematologic malignancies

    PubMed Central

    Saulle, Ernestina; Castelli, Germana; Pelosi, Elvira

    2016-01-01

    Studies carried out in the last years have improved the understanding of the cellular and molecular mechanisms controlling angiogenesis during adult life in normal and pathological conditions. Some of these studies have led to the identification of some progenitor cells that sustain angiogenesis through indirect, paracrine mechanisms (hematopoietic angiogenic cells) and through direct mechanisms, i.e., through their capacity to generate a progeny of phenotypically and functionally competent endothelial cells [endothelial colony forming cells (ECFCs)]. The contribution of these progenitors to angiogenetic processes under physiological and pathological conditions is intensively investigated. Angiogenetic mechanisms are stimulated in various hematological malignancies, including chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myelodysplastic syndromes and multiple myeloma, resulting in an increased angiogenesis that contributes to disease progression. In some of these conditions there is preliminary evidence that some endothelial cells could derive from the malignant clone, thus leading to the speculation that the leukemic cell derives from the malignant transformation of a hemangioblastic progenitor, i.e., of a cell capable of differentiation to the hematopoietic and to the endothelial cell lineages. Our understanding of the mechanisms underlying increased angiogenesis in these malignancies not only contributed to a better knowledge of the mechanisms responsible for tumor progression, but also offered the way for the discovery of new therapeutic targets. PMID:27583252

  17. Endothelial progenitor cells in hematologic malignancies.

    PubMed

    Testa, Ugo; Saulle, Ernestina; Castelli, Germana; Pelosi, Elvira

    2016-01-01

    Studies carried out in the last years have improved the understanding of the cellular and molecular mechanisms controlling angiogenesis during adult life in normal and pathological conditions. Some of these studies have led to the identification of some progenitor cells that sustain angiogenesis through indirect, paracrine mechanisms (hematopoietic angiogenic cells) and through direct mechanisms, i.e., through their capacity to generate a progeny of phenotypically and functionally competent endothelial cells [endothelial colony forming cells (ECFCs)]. The contribution of these progenitors to angiogenetic processes under physiological and pathological conditions is intensively investigated. Angiogenetic mechanisms are stimulated in various hematological malignancies, including chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myelodysplastic syndromes and multiple myeloma, resulting in an increased angiogenesis that contributes to disease progression. In some of these conditions there is preliminary evidence that some endothelial cells could derive from the malignant clone, thus leading to the speculation that the leukemic cell derives from the malignant transformation of a hemangioblastic progenitor, i.e., of a cell capable of differentiation to the hematopoietic and to the endothelial cell lineages. Our understanding of the mechanisms underlying increased angiogenesis in these malignancies not only contributed to a better knowledge of the mechanisms responsible for tumor progression, but also offered the way for the discovery of new therapeutic targets. PMID:27583252

  18. Progenitor endothelial cell involvement in Alzheimer's disease

    SciTech Connect

    Budinger, Thomas F.

    2003-05-01

    There is compelling evidence that endothelial cells of the brain and periphery are dysfunctional in Alzheimer's Disease. There is evidence for a fundamental defect in, or abnormal aging of, endothelial progenitor cells in atherosclerosis. The possibility that endothelial cell defects are a primary cause for Alzheimer's Disease or other dementias can be researched by molecular and cell biology studies as well as cell trafficking studies using recently demonstrated molecular imaging methods. The evidence for abnormal endothelial function and the methods to explore this hypothesis are presented.

  19. Adult Stem and Progenitor Cells

    NASA Astrophysics Data System (ADS)

    Geraerts, Martine; Verfaillie, Catherine M.

    The discovery of adult stem cells in most adult tissues is the basis of a number of clinical studies that are carried out, with therapeutic use of hematopoietic stem cells as a prime example. Intense scientific debate is still ongoing as to whether adult stem cells may have a greater plasticity than previously thought. Although cells with some features of embryonic stem cells that, among others, express Oct4, Nanog and SSEA1 are isolated from fresh tissue, it is not clear if the greater differentiation potential is acquired during cell culture. Moreover, adult more pluripotent cells do not have all pluripotent characteristics typical for embryonic stem cells. Recently, some elegant studies were published in which adult cells could be completely reprogrammed to embryonic stem cell-like cells by overexpression of some key transcription factors for pluripotency (Oct4, Sox2, Klf4 and c-Myc). It will be interesting for the future to investigate the exact mechanisms underlying this reprogramming and whether similar transcription factor pathways are present and/or can be activated in adult more pluripotent stem cells.

  20. Epidermal growth factor signaling in transformed cells

    PubMed Central

    Lindsey, Stephan; Langhans, Sigrid A.

    2016-01-01

    Members of the epidermal growth factor receptor (EGFR/ErbB) family play a critical role in normal cell growth and development. However, many ErbB family members, especially EGFR, are aberrantly expressed or deregulated in tumors and are thought to play crucial roles in cancer development and metastatic progression. In this chapter, we provide an overview of key mechanisms contributing to aberrant EGFR/ErbB signaling in transformed cells which results in many phenotypic changes associated with the earliest stages of tumor formation, including several hallmarks of epithelial-to-mesenchymal transition (EMT). These changes often occur through interaction with other major signaling pathways important to tumor progression resulting in a multitude of transcriptional changes that ultimately impact cell morphology, proliferation and adhesion, all of which are crucial for tumor progression. The resulting mesh of signaling networks will need to be taken into account as new regimens are designed for targeting EGFR for therapeutic intervention. As new insights into the molecular mechanisms of the cross-talk of EGFR signaling with other signaling pathways and their role in therapeutic resistance to anti-EGFR therapies are gained a continual reassessment of clinical therapeutic regimes and strategies will be required. Understanding the consequences and complexity of EGF signaling and how it relates to tumor progression is critical for the development of clinical compounds and establishing clinical protocols for the treatment of cancer. PMID:25619714

  1. Specification of epidermal cell fate in plant shoots.

    PubMed

    Takada, Shinobu; Iida, Hiroyuki

    2014-01-01

    Land plants have evolved a single layer of epidermal cells, which are characterized by mostly anticlinal cell division patterns, formation of a waterproof coat called cuticle, and unique cell types such as stomatal guard cells and trichomes. The shoot epidermis plays important roles not only to protect plants from dehydration and pathogens but also to ensure their proper organogenesis and growth control. Extensive molecular genetic studies in Arabidopsis and maize have identified a number of genes that are required for epidermal cell differentiation. However, the mechanism that specifies shoot epidermal cell fate during plant organogenesis remains largely unknown. Particularly, little is known regarding positional information that should restrict epidermal cell fate to the outermost cell layer of the developing organs. Recent studies suggested that certain members of the HD-ZIP class IV homeobox genes are possible master regulators of shoot epidermal cell fate. Here, we summarize the roles of the regulatory genes that are involved in epidermal cell fate specification and discuss the possible mechanisms that limit the expression and/or activity of the master transcriptional regulators to the outermost cell layer in plant shoots. PMID:24616724

  2. Nutritional regulation of stem and progenitor cells in Drosophila

    PubMed Central

    Shim, Jiwon; Gururaja-Rao, Shubha; Banerjee, Utpal

    2013-01-01

    Stem cells and their progenitors are maintained within a microenvironment, termed the niche, through local cell-cell communication. Systemic signals originating outside the niche also affect stem cell and progenitor behavior. This review summarizes studies that pertain to nutritional effects on stem and progenitor cell maintenance and proliferation in Drosophila. Multiple tissue types are discussed that utilize the insulin-related signaling pathway to convey nutritional information either directly to these progenitors or via other cell types within the niche. The concept of systemic control of these cell types is not limited to Drosophila and may be functional in vertebrate systems, including mammals. PMID:24255094

  3. Anti-epidermal-cell-surface pemphigus antibody detaches viable epidermal cells from culture plates by activation of proteinase.

    PubMed Central

    Farb, R M; Dykes, R; Lazarus, G S

    1978-01-01

    Immunoglobulin from pemphigus patients binds to the surface of mouse epidermal cells in culture. Cells incubated with the pemphigus antibody are easily detached from culture plates whereas cells incubated with serum from normal patients remain on the plate. Pemphigus antibody-mediated cell detachment is blocked by the addition of the proteinase inhibitors soybean trypsin inhibitor and alpha2-macroglobulin to the culture media. Detachable cells are viable, and activation of the complement cascade is not necessary for cell detachment. The anti-cell-surface antibody of pemphigus appears to disrupt adhesion between viable epidermal cells by activation of proteinase. Images PMID:272663

  4. PET imaging of adoptive progenitor cell therapies.

    SciTech Connect

    Gelovani, Juri G.

    2008-05-13

    Objectives. The overall objective of this application is to develop novel technologies for non-invasive imaging of adoptive stem cell-based therapies with positron emission tomography (PET) that would be applicable to human patients. To achieve this objective, stem cells will be genetically labeled with a PET-reporter gene and repetitively imaged to assess their distribution, migration, differentiation, and persistence using a radiolabeled reporter probe. This new imaging technology will be tested in adoptive progenitor cell-based therapy models in animals, including: delivery pro-apoptotic genes to tumors, and T-cell reconstitution for immunostimulatory therapy during allogeneic bone marrow progenitor cell transplantation. Technical and Scientific Merits. Non-invasive whole body imaging would significantly aid in the development and clinical implementation of various adoptive progenitor cell-based therapies by providing the means for non-invasive monitoring of the fate of injected progenitor cells over a long period of observation. The proposed imaging approaches could help to address several questions related to stem cell migration and homing, their long-term viability, and their subsequent differentiation. The ability to image these processes non-invasively in 3D and repetitively over a long period of time is very important and will help the development and clinical application of various strategies to control and direct stem cell migration and differentiation. Approach to accomplish the work. Stem cells will be genetically with a reporter gene which will allow for repetitive non-invasive “tracking” of the migration and localization of genetically labeled stem cells and their progeny. This is a radically new approach that is being developed for future human applications and should allow for a long term (many years) repetitive imaging of the fate of tissues that develop from the transplanted stem cells. Why the approach is appropriate. The novel approach to

  5. Human neural progenitors express functional lysophospholipid receptors that regulate cell growth and morphology

    PubMed Central

    Hurst, Jillian H; Mumaw, Jennifer; Machacek, David W; Sturkie, Carla; Callihan, Phillip; Stice, Steve L; Hooks, Shelley B

    2008-01-01

    Background Lysophospholipids regulate the morphology and growth of neurons, neural cell lines, and neural progenitors. A stable human neural progenitor cell line is not currently available in which to study the role of lysophospholipids in human neural development. We recently established a stable, adherent human embryonic stem cell-derived neuroepithelial (hES-NEP) cell line which recapitulates morphological and phenotypic features of neural progenitor cells isolated from fetal tissue. The goal of this study was to determine if hES-NEP cells express functional lysophospholipid receptors, and if activation of these receptors mediates cellular responses critical for neural development. Results Our results demonstrate that Lysophosphatidic Acid (LPA) and Sphingosine-1-phosphate (S1P) receptors are functionally expressed in hES-NEP cells and are coupled to multiple cellular signaling pathways. We have shown that transcript levels for S1P1 receptor increased significantly in the transition from embryonic stem cell to hES-NEP. hES-NEP cells express LPA and S1P receptors coupled to Gi/o G-proteins that inhibit adenylyl cyclase and to Gq-like phospholipase C activity. LPA and S1P also induce p44/42 ERK MAP kinase phosphorylation in these cells and stimulate cell proliferation via Gi/o coupled receptors in an Epidermal Growth Factor Receptor (EGFR)- and ERK-dependent pathway. In contrast, LPA and S1P stimulate transient cell rounding and aggregation that is independent of EGFR and ERK, but dependent on the Rho effector p160 ROCK. Conclusion Thus, lysophospholipids regulate neural progenitor growth and morphology through distinct mechanisms. These findings establish human ES cell-derived NEP cells as a model system for studying the role of lysophospholipids in neural progenitors. PMID:19077254

  6. Redefining endothelial progenitor cells via clonal analysis and hematopoietic stem/progenitor cell principals

    PubMed Central

    Mead, Laura E.; Prater, Daniel; Krier, Theresa R.; Mroueh, Karim N.; Li, Fang; Krasich, Rachel; Temm, Constance J.; Prchal, Josef T.

    2007-01-01

    The limited vessel-forming capacity of infused endothelial progenitor cells (EPCs) into patients with cardiovascular dysfunction may be related to a misunderstanding of the biologic potential of the cells. EPCs are generally identified by cell surface antigen expression or counting in a commercially available kit that identifies “endothelial cell colony-forming units” (CFU-ECs). However, the origin, proliferative potential, and differentiation capacity of CFU-ECs is controversial. In contrast, other EPCs with blood vessel-forming ability, termed endothelial colony-forming cells (ECFCs), have been isolated from human peripheral blood. We compared the function of CFU-ECs and ECFCs and determined that CFU-ECs are derived from the hematopoietic system using progenitor assays, and analysis of donor cells from polycythemia vera patients harboring a Janus kinase 2 V617F mutation in hematopoietic stem cell clones. Further, CFU-ECs possess myeloid progenitor cell activity, differentiate into phagocytic macrophages, and fail to form perfused vessels in vivo. In contrast, ECFCs are clonally distinct from CFU-ECs, display robust proliferative potential, and form perfused vessels in vivo. Thus, these studies establish that CFU-ECs are not EPCs and the role of these cells in angiogenesis must be re-examined prior to further clinical trials, whereas ECFCs may serve as a potential therapy for vascular regeneration. PMID:17053059

  7. Redefining endothelial progenitor cells via clonal analysis and hematopoietic stem/progenitor cell principals.

    PubMed

    Yoder, Mervin C; Mead, Laura E; Prater, Daniel; Krier, Theresa R; Mroueh, Karim N; Li, Fang; Krasich, Rachel; Temm, Constance J; Prchal, Josef T; Ingram, David A

    2007-03-01

    The limited vessel-forming capacity of infused endothelial progenitor cells (EPCs) into patients with cardiovascular dysfunction may be related to a misunderstanding of the biologic potential of the cells. EPCs are generally identified by cell surface antigen expression or counting in a commercially available kit that identifies "endothelial cell colony-forming units" (CFU-ECs). However, the origin, proliferative potential, and differentiation capacity of CFU-ECs is controversial. In contrast, other EPCs with blood vessel-forming ability, termed endothelial colony-forming cells (ECFCs), have been isolated from human peripheral blood. We compared the function of CFU-ECs and ECFCs and determined that CFU-ECs are derived from the hematopoietic system using progenitor assays, and analysis of donor cells from polycythemia vera patients harboring a Janus kinase 2 V617F mutation in hematopoietic stem cell clones. Further, CFU-ECs possess myeloid progenitor cell activity, differentiate into phagocytic macrophages, and fail to form perfused vessels in vivo. In contrast, ECFCs are clonally distinct from CFU-ECs, display robust proliferative potential, and form perfused vessels in vivo. Thus, these studies establish that CFU-ECs are not EPCs and the role of these cells in angiogenesis must be re-examined prior to further clinical trials, whereas ECFCs may serve as a potential therapy for vascular regeneration. PMID:17053059

  8. Stem cells and progenitor cells in renal disease.

    PubMed

    Haller, Hermann; de Groot, Kirsten; Bahlmann, Ferdinand; Elger, Marlies; Fliser, Danilo

    2005-11-01

    Stem cells and progenitor cells are necessary for repair and regeneration of injured renal tissue. Infiltrating or resident stem cells can contribute to the replacement of lost or damaged tissue. However, the regulation of circulating progenitor cells is not well understood. We have analyzed the effects of erythropoietin on circulating progenitor cells and found that low levels of erythropoietin induce mobilization and differentiation of endothelial progenitor cells. In an animal model of 5/6 nephrectomy we could demonstrate that erythropoietin ameliorates tissue injury. Full regeneration of renal tissue demands the existence of stem cells and an adequate local "milieu," a so-called stem cell niche. We have previously described a stem cell niche in the kidneys of the dogfish, Squalus acanthus. Further analysis revealed that in the regenerating zone of the shark kidney, stem cells exist that can be induced by loss of renal tissue to form new glomeruli. Such animal models improve our understanding of stem cell behavior in the kidney and may eventually contribute to novel therapies. PMID:16221168

  9. TWEAK induces liver progenitor cell proliferation.

    PubMed

    Jakubowski, Aniela; Ambrose, Christine; Parr, Michael; Lincecum, John M; Wang, Monica Z; Zheng, Timothy S; Browning, Beth; Michaelson, Jennifer S; Baetscher, Manfred; Baestcher, Manfred; Wang, Bruce; Bissell, D Montgomery; Burkly, Linda C

    2005-09-01

    Progenitor ("oval") cell expansion accompanies many forms of liver injury, including alcohol toxicity and submassive parenchymal necrosis as well as experimental injury models featuring blocked hepatocyte replication. Oval cells can potentially become either hepatocytes or biliary epithelial cells and may be critical to liver regeneration, particularly when hepatocyte replication is impaired. The regulation of oval cell proliferation is incompletely understood. Herein we present evidence that a TNF family member called TWEAK (TNF-like weak inducer of apoptosis) stimulates oval cell proliferation in mouse liver through its receptor Fn14. TWEAK has no effect on mature hepatocytes and thus appears to be selective for oval cells. Transgenic mice overexpressing TWEAK in hepatocytes exhibit periportal oval cell hyperplasia. A similar phenotype was obtained in adult wild-type mice, but not Fn14-null mice, by administering TWEAK-expressing adenovirus. Oval cell expansion induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) was significantly reduced in Fn14-null mice as well as in adult wild-type mice with a blocking anti-TWEAK mAb. Importantly, TWEAK stimulated the proliferation of an oval cell culture model. Finally, we show increased Fn14 expression in chronic hepatitis C and other human liver diseases relative to its expression in normal liver, which suggests a role for the TWEAK/Fn14 pathway in human liver injury. We conclude that TWEAK has a selective mitogenic effect for liver oval cells that distinguishes it from other previously described growth factors. PMID:16110324

  10. Defining human dendritic cell progenitors by multiparametric flow cytometry.

    PubMed

    Breton, Gaëlle; Lee, Jaeyop; Liu, Kang; Nussenzweig, Michel C

    2015-09-01

    Human dendritic cells (DCs) develop from progressively restricted bone marrow (BM) progenitors: these progenitor cells include granulocyte, monocyte and DC progenitor (GMDP) cells; monocyte and DC progenitor (MDP) cells; and common DC progenitor (CDP) and DC precursor (pre-DC) cells. These four DC progenitors can be defined on the basis of the expression of surface markers such as CD34 and hematopoietin receptors. In this protocol, we describe five multiparametric flow cytometry panels that can be used as a tool (i) to simultaneously detect or phenotype the four DC progenitors, (ii) to isolate DC progenitors to enable in vitro differentiation or (iii) to assess the in vitro differentiation and proliferation of DC progenitors. The entire procedure from isolation of cells to flow cytometry can be completed in 3-7 h. This protocol provides optimized antibody panels, as well as gating strategies, for immunostaining of BM and cord blood specimens to study human DC hematopoiesis in health, disease and vaccine settings. PMID:26292072

  11. Defining human dendritic cell progenitors by multiparametric flow cytometry

    PubMed Central

    Breton, Gaëlle; Lee, Jaeyop; Liu, Kang; Nussenzweig, Michel C

    2015-01-01

    Human dendritic cells (DCs) develop from progressively restricted bone marrow (BM) progenitors: these progenitor cells include granulocyte, monocyte and DC progenitor (GMDP) cells; monocyte and DC progenitor (MDP) cells; and common DC progenitor (CDP) and DC precursor (pre-DC) cells. These four DC progenitors can be defined on the basis of the expression of surface markers such as CD34 and hematopoietin receptors. In this protocol, we describe five multiparametric flow cytometry panels that can be used as a tool (i) to simultaneously detect or phenotype the four DC progenitors, (ii) to isolate DC progenitors to enable in vitro differentiation or (iii) to assess the in vitro differentiation and proliferation of DC progenitors. The entire procedure from isolation of cells to flow cytometry can be completed in 3–7 h. This protocol provides optimized antibody panels, as well as gating strategies, for immunostaining of BM and cord blood specimens to study human DC hematopoiesis in health, disease and vaccine settings. PMID:26292072

  12. Do epidermal lens cells facilitate the absorptance of diffuse light?

    PubMed

    Brodersen, Craig R; Vogelmann, Thomas C

    2007-07-01

    Many understory plants rely on diffuse light for photosynthesis because direct light is usually scattered by upper canopy layers before it strikes the forest floor. There is a considerable gap in the literature concerning the interaction of direct and diffuse light with leaves. Some understory plants have well-developed lens-shaped epidermal cells, which have long been thought to increase the absorption of diffuse light. To assess the role of epidermal cell shape in capturing direct vs. diffuse light, we measured leaf reflectance and transmittance with an integrating sphere system using leaves with flat (Begonia erythrophylla, Citrus reticulata, and Ficus benjamina) and lens-shaped epidermal cells (B. bowerae, Colocasia esculenta, and Impatiens velvetea). In all species examined, more light was absorbed when leaves were irradiated with direct as opposed to diffuse light. When leaves were irradiated with diffuse light, more light was transmitted and more was reflected in both leaf types, resulting in absorptance values 2-3% lower than in leaves irradiated with direct light. These data suggest that lens-shaped epidermal cells do not aid the capture of diffuse light. Palisade and mesophyll cell anatomy and leaf thickness appear to have more influence in the capture and absorption of light than does epidermal cell shape. PMID:21636475

  13. Cardiogenic Differentiation and Transdifferentiation of Progenitor Cells

    PubMed Central

    Reinecke, Hans; Minami, Elina; Zhu, Wei-Zhong; Laflamme, Michael A.

    2009-01-01

    In recent years, cell transplantation has drawn tremendous interest as a novel approach to preserving or even restoring contractile function to infarcted hearts. A typical human infarct involves the loss of approximately one billion cardiomyocytes, and so many investigators have sought to identify endogenous or exogenous stem cells with the capacity to differentiate into committed cardiomyocytes and repopulate lost myocardium. As a result of these efforts, dozens of stem cell types have been reported to have cardiac potential. These include pluripotent embryonic stem cells as well various adult stem cells resident in compartments including bone marrow, peripheral tissues, and the heart itself. Some of these cardiogenic progenitors have been reported to contribute replacement muscle through endogenous reparative processes or via cell transplantation in preclinical cardiac injury models. However, considerable disagreement exists regarding the efficiency and even the reality of cardiac differentiation by many of these stem cell types, making these issues a continuing source of controversy in the field. In this review, we consider approaches to cell fate mapping and establishing the cardiac phenotype, as well as the current state of the evidence for the cardiogenic and regenerative potential of the major candidate stem cell types. PMID:18988903

  14. Murine Mueller cells are progenitor cells for neuronal cells and fibrous tissue cells

    SciTech Connect

    Florian, Christian; Langmann, Thomas; Weber, Bernhard H.F.; Morsczeck, Christian

    2008-09-19

    Mammalian Mueller cells have been reported to possess retinal progenitor cell properties and generate new neurons after injury. This study investigates murine Mueller cells under in vitro conditions for their capability of dedifferentiation into retinal progenitor cells. Mueller cells were isolated from mouse retina, and proliferating cells were expanded in serum-containing medium. For dedifferentiation, the cultured cells were transferred to serum-replacement medium (SRM) at different points in time after their isolation. Interestingly, early cell passages produced fibrous tissue in which extracellular matrix proteins and connective tissue markers were differentially expressed. In contrast, aged Mueller cell cultures formed neurospheres in SRM that are characteristic for neuronal progenitor cells. These neurospheres differentiated into neuron-like cells after cultivation on laminin/ornithine cell culture substrate. Here, we report for the first time that murine Mueller cells can be progenitors for both, fibrous tissue cells and neuronal cells, depending on the age of the cell culture.

  15. Genetically Induced Cell Death in Bulge Stem Cells Reveals Their Redundancy for Hair and Epidermal Regeneration

    PubMed Central

    Driskell, Iwona; Oeztuerk-Winder, Feride; Humphreys, Peter; Frye, Michaela

    2015-01-01

    Adult mammalian epidermis contains multiple stem cell populations in which quiescent and more proliferative stem and progenitor populations coexist. However, the precise interrelation of these populations in homeostasis remains unclear. Here, we blocked the contribution of quiescent keratin 19 (K19)-expressing bulge stem cells to hair follicle formation through genetic ablation of the essential histone methyltransferase Setd8 that is required for the maintenance of adult skin. Deletion of Setd8 eliminated the contribution of bulge cells to hair follicle regeneration through inhibition of cell division and induction of cell death, but the growth and morphology of hair follicles were unaffected. Furthermore, ablation of Setd8 in the hair follicle bulge blocked the contribution of K19-postive stem cells to wounded epidermis, but the wound healing process was unaltered. Our data indicate that quiescent bulge stem cells are dispensable for hair follicle regeneration and epidermal injury in the short term and support the hypothesis that quiescent and cycling stem cell populations are equipotent. Stem Cells 2015;33:988–998 PMID:25447755

  16. Caspase-1 mediates hyperlipidemia-weakened progenitor cell vessel repair

    PubMed Central

    Li, Ya-Feng; Huang, Xiao; Li, Xinyuan; Gong, Ren; Yin, Ying; Nelson, Jun; Gao, Erhe; Zhang, Hongyu; Hoffman, Nicholas E.; Houser, Steven R.; Madesh, Muniswamy; Tilley, Douglas G.; Choi, Eric T.; Jiang, Xiaohua; Huang, Cong-Xin; Wang, Hong; Yang, Xiao-Feng

    2015-01-01

    Caspase-1 activation senses metabolic danger-associated molecular patterns (DAMPs) and mediates the initiation of inflammation in endothelial cells. Here, we examined whether the caspase-1 pathway is responsible for sensing hyperlipidemia as a DAMP in bone marrow (BM)-derived Stem cell antigen-1 positive (Sca-1+) stem/progenitor cells and weakening their angiogenic ability. Using biochemical methods, gene knockout, cell therapy and myocardial infarction (MI) models, we had the following findings: 1) Hyperlipidemia induces caspase-1 activity in mouse Sca-1+ progenitor cells in vivo; 2) Caspase-1 contributes to hyperlipidemia-induced modulation of vascular cell death-related gene expression in vivo; 3) Injection of Sca-1+ progenitor cells from caspase-1−/− mice improves endothelial capillary density in heart and decreases cardiomyocyte death in a mouse model of MI; and 4) Caspase-1−/− Sca-1+ progenitor cell therapy improves mouse cardiac function after MI. Our results provide insight on how hyperlipidemia activates caspase-1 in Sca-1+ progenitor cells, which subsequently weakens Sca-1+ progenitor cell repair of vasculature injury. These results demonstrate the therapeutic potential of caspase-1 inhibition in improving progenitor cell therapy for MI. PMID:26709768

  17. Clonal proliferation of multipotent stem/progenitor cells in the neonatal and adult salivary glands

    SciTech Connect

    Kishi, Teruki; Takao, Tukasa; Fujita, Kiyohide; Taniguchi, Hideki . E-mail: rtanigu@med.yokohama-cu.ac.jp

    2006-02-10

    Salivary gland stem/progenitor cells are thought to be present in intercalated ductal cells, but the fact is unclear. In this study, we sought to clarify if stem/progenitor cells are present in submandibular glands using colony assay, which is one of the stem cell assay methods. Using a low-density culture of submandibular gland cells of neonatal rats, we developed a novel culture system that promotes single cell colony formation. Average doubling time for the colony-forming cells was 24.7 (SD = {+-}7.02) h, indicating high proliferative potency. When epidermal growth factor (EGF) and hepatocyte growth factor (HGF) were added to the medium, the number of clonal colonies increased greater than those cultured without growth factors (13.2 {+-} 4.18 vs. 4.5 {+-} 1.73). The RT-PCR and immunostaining demonstrated expressing acinar, ductal, and myoepithelial cell lineage markers. This study demonstrated the presence of the salivary gland stem/progenitor cells that are highly proliferative and multipotent in salivary glands.

  18. Low calcium culture condition induces mesenchymal cell-like phenotype in normal human epidermal keratinocytes

    SciTech Connect

    Takagi, Ryo; Yamato, Masayuki; Murakami, Daisuke; Sugiyama, Hiroaki; Okano, Teruo

    2011-08-26

    Highlights: {yields} Normal human epidermal keratinocytes serially cultured under low calcium concentration were cytokeratin and vimentin double positive cells. {yields} The human keratinocytes expressed some epithelial stem/progenitor cell makers, mesenchymal cell markers, and markers of epithelial-mesenchymal transition. {yields} Mesenchymal cell-like phenotype in the keratinocytes was suppressed under high-calcium condition. -- Abstract: Epithelial-mesenchymal transition (EMT) is an important cellular phenomenon in organ developments, cancer invasions, and wound healing, and many types of transformed cell lines are used for investigating for molecular mechanisms of EMT. However, there are few reports for EMT in normal human epithelial cells, which are non-transformed or non-immortalized cells, in vitro. Therefore, normal human epidermal keratinocytes (NHEK) serially cultured in low-calcium concentration medium (LCM) were used for investigating relations between differentiation and proliferation and mesenchymal-like phenotype in the present study, since long-term cultivation of NHEK is achieved in LCM. Interestingly, NHEK serially cultured in LCM consisted essentially of cytokeratin-vimentin double positive cells (98%), although the NHEK exhibited differentiation under high-calcium culture condition with 3T3 feeder layer. The vimentin expression was suppressed under high-calcium condition. These results may indicate the importance of mesenchymal-like phenotype for serially cultivation of NHEK in vitro.

  19. Differential Effects of Isoxazole-9 on Neural Stem/Progenitor Cells, Oligodendrocyte Precursor Cells, and Endothelial Progenitor Cells

    PubMed Central

    Maki, Takakuni; Shindo, Akihiro; Osumi, Noriko; Zhao, Jing; Lin, Hong; Holder, Julie C.; Chuang, Tsu Tshen; McNeish, John D.; Arai, Ken; Lo, Eng H.

    2015-01-01

    Adult mammalian brain can be plastic after injury and disease. Therefore, boosting endogenous repair mechanisms would be a useful therapeutic approach for neurological disorders. Isoxazole-9 (Isx-9) has been reported to enhance neurogenesis from neural stem/progenitor cells (NSPCs). However, the effects of Isx-9 on other types of progenitor/precursor cells remain mostly unknown. In this study, we investigated the effects of Isx-9 on the three major populations of progenitor/precursor cells in brain: NSPCs, oligodendrocyte precursor cells (OPCs), and endothelial progenitor cells (EPCs). Cultured primary NSPCs, OPCs, or EPCs were treated with various concentrations of Isx-9 (6.25, 12.5, 25, 50 μM), and their cell numbers were counted in a blinded manner. Isx-9 slightly increased the number of NSPCs and effectively induced neuronal differentiation of NSPCs. However, Isx-9 significantly decreased OPC number in a concentration-dependent manner, suggesting cytotoxicity. Isx-9 did not affect EPC cell number. But in a matrigel assay of angiogenesis, Isx-9 significantly inhibited tube formation in outgrowth endothelial cells derived from EPCs. This potential anti-tube-formation effect of Isx-9 was confirmed in a brain endothelial cell line. Taken together, our data suggest that mechanisms and targets for promoting stem/progenitor cells in the central nervous system may significantly differ between cell types. PMID:26407349

  20. The dynamics of murine mammary stem/progenitor cells

    PubMed Central

    DONG, Qiaoxiang; SUN, Lu-Zhe

    2014-01-01

    The stem/progenitor cells in the murine mammary gland are a highly dynamic population of cells that are responsible for ductal elongation in puberty, homeostasis maintenance in adult, and lobulo-alveolar genesis during pregnancy. In recent years understanding the epithelial cell hierarchy within the mammary gland is becoming particularly important as these different stem/progenitor cells were perceived to be the cells of origin for various subtypes of breast cancer. Although significant advances have been made in enrichment and isolation of stem/progenitor cells by combinations of antibodies against cell surface proteins together with flow cytometry, and in identification of stem/progenitor cells with multi-lineage differentiation and self-renewal using mammary fat pad reconstitution assay and in vivo genetic labeling technique, a clear understanding of how these different stem/progenitors are orchestrated in the mammary gland is still lacking. Here we discuss the different in vivo and in vitro methods currently available for stem/progenitor identification, their associated caveats, and a possible new hierarchy model to reconcile various putative stem/progenitor cell populations identified by different research groups. PMID:25580105

  1. Fate by Chance, not by Choice: Epidermal Stem Cells Go Live.

    PubMed

    Gonzalez-Celeiro, Meryem; Zhang, Bing; Hsu, Ya-Chieh

    2016-07-01

    The skin epidermis is constantly renewed by epidermal stem cells. In a recent Science paper, Rompolas et al. utilize live imaging to track epidermal stem cells over their lifetimes. Their findings provide new insights into epidermal stem cell behaviors and unravel how newly generated cells are integrated into pre-existing tissues. PMID:27392221

  2. Cell-Surface Protein Profiling Identifies Distinctive Markers of Progenitor Cells in Human Skeletal Muscle.

    PubMed

    Uezumi, Akiyoshi; Nakatani, Masashi; Ikemoto-Uezumi, Madoka; Yamamoto, Naoki; Morita, Mitsuhiro; Yamaguchi, Asami; Yamada, Harumoto; Kasai, Takehiro; Masuda, Satoru; Narita, Asako; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi; Fukada, So-Ichiro; Nishino, Ichizo; Tsuchida, Kunihiro

    2016-08-01

    Skeletal muscle contains two distinct stem/progenitor populations. One is the satellite cell, which acts as a muscle stem cell, and the other is the mesenchymal progenitor, which contributes to muscle pathogeneses such as fat infiltration and fibrosis. Detailed and accurate characterization of these progenitors in humans remains elusive. Here, we performed comprehensive cell-surface protein profiling of the two progenitor populations residing in human skeletal muscle and identified three previously unrecognized markers: CD82 and CD318 for satellite cells and CD201 for mesenchymal progenitors. These markers distinguish myogenic and mesenchymal progenitors, and enable efficient isolation of the two types of progenitors. Functional study revealed that CD82 ensures expansion and preservation of myogenic progenitors by suppressing excessive differentiation, and CD201 signaling favors adipogenesis of mesenchymal progenitors. Thus, cell-surface proteins identified here are not only useful markers but also functionally important molecules, and provide valuable insight into human muscle biology and diseases. PMID:27509136

  3. Harnessing endogenous stem/progenitor cells for tendon regeneration

    PubMed Central

    Lee, Chang H.; Lee, Francis Y.; Tarafder, Solaiman; Kao, Kristy; Jun, Yena; Yang, Guodong; Mao, Jeremy J.

    2015-01-01

    Current stem cell–based strategies for tissue regeneration involve ex vivo manipulation of these cells to confer features of the desired progenitor population. Recently, the concept that endogenous stem/progenitor cells could be used for regenerating tissues has emerged as a promising approach that potentially overcomes the obstacles related to cell transplantation. Here we applied this strategy for the regeneration of injured tendons in a rat model. First, we identified a rare fraction of tendon cells that was positive for the known tendon stem cell marker CD146 and exhibited clonogenic capacity, as well as multilineage differentiation ability. These tendon-resident CD146+ stem/progenitor cells were selectively enriched by connective tissue growth factor delivery (CTGF delivery) in the early phase of tendon healing, followed by tenogenic differentiation in the later phase. The time-controlled proliferation and differentiation of CD146+ stem/progenitor cells by CTGF delivery successfully led to tendon regeneration with densely aligned collagen fibers, normal level of cellularity, and functional restoration. Using siRNA knockdown to evaluate factors involved in tendon generation, we demonstrated that the FAK/ERK1/2 signaling pathway regulates CTGF-induced proliferation and differentiation of CD146+ stem/progenitor cells. Together, our findings support the use of endogenous stem/progenitor cells as a strategy for tendon regeneration without cell transplantation and suggest this approach warrants exploration in other tissues. PMID:26053662

  4. Recent progress on normal and malignant pancreatic stem/progenitor cell research: therapeutic implications for the treatment of type 1 or 2 diabetes mellitus and aggressive pancreatic cancer

    PubMed Central

    Mimeault, M; Batra, S K

    2010-01-01

    Recent progress on pancreatic stem/progenitor cell research has revealed that the putative multipotent pancreatic stem/progenitor cells and/or more committed beta cell precursors may persist in the pancreatic gland in adult life. The presence of immature pancreatic cells with stem cell-like properties offers the possibility of stimulating their in vivo expansion and differentiation or to use their ex vivo expanded progenies for beta cell replacement-based therapies for type 1 or 2 diabetes mellitus in humans. In addition, the transplantation of either insulin-producing beta cells derived from embryonic, fetal and other tissue-resident adult stem/progenitor cells or genetically modified adult stem/progenitor cells may also constitute alternative promising therapies for treating diabetic patients. The genetic and/or epigenetic alterations in putative pancreatic adult stem/progenitor cells and/or their early progenies may, however, contribute to their acquisition of a dysfunctional behaviour as well as their malignant transformation into pancreatic cancer stem/progenitor cells. More particularly, the activation of distinct tumorigenic signalling cascades, including the hedgehog, epidermal growth factor–epidermal growth factor receptor (EGF–EGFR) system, wingless ligand (Wnt)/β-catenin and/or stromal cell-derived factor-1 (SDF-1)–CXC chemokine receptor 4 (CXCR4) pathways may play a major role in the sustained growth, survival, metastasis and/or drug resistance of pancreatic cancer stem/progenitor cells and their further differentiated progenies. The combination of drugs that target the oncogenic elements in pancreatic cancer stem/progenitor cells and their microenvironment, with the conventional chemotherapeutic regimens, could represent promising therapeutic strategies. These novel targeted therapies should lead to the development of more effective treatments of locally advanced and metastatic pancreatic cancers, which remain incurable with current therapies

  5. [Umbilical cord hematopoietic progenitor cells bank].

    PubMed

    Morales, V H; Milone, J; Etchegoyen, O; Bordone, J; Uranga, A

    2001-01-01

    Transplantation of hematopoietic progenitor cells (HPC) from bone marrow and mobilized peripheral blood is a standard therapy in malignant and non malignant diseases. The lack of suitable donors is an important limitation. The discovery that umbilical cord blood (CB) contains high numbers of HPC that can be used as an alternative source for allogeneic stem cell transplantation led ITMO to establish BANCEL, the first Argentine and Latinoamerican experience of its kind. The blood remaining in the umbilical cord and in the placenta was requested from women who were in the last quarter of pregnancy. An informed consent together with a medical record focused on family disease was completed. Out of 65 donations, 55 (85%) were collected and 51 (78%) were cryopreserved. Mean collected volume was 110 ml with 68% (75 ml) reduction and mean cryopreservation of 35 ml; ABO and Rh blood group systems were determined, HLA, class I, A and B loci, and class II, DR locus were typed by molecular biology methods using PCR-SSOP. Infectious disease screening was carried out for brucellosis, syphilis, Chagas, hepatitis B and C, HIV I and II, HTLV I and II, toxoplasmosis and cytomegalovirus. Two positive units for hepatitis B (anticore) and two positive units for Chagas were discarded. The quantity of total nucleated cells (TNC), CD34+ cells and the clonogenic capacity were determined twice at the collection and after the procedures of volume reduction previous to cryopreservation. A 5% reduction in both TNC and CD34 cells and a 10% in the colony forming units (CFU) were detected. A good correlation coefficient between TNC and CFU was obtained. PMID:11808425

  6. Efficient Generation of NKX6-1+ Pancreatic Progenitors from Multiple Human Pluripotent Stem Cell Lines

    PubMed Central

    Nostro, M. Cristina; Sarangi, Farida; Yang, Chaoxing; Holland, Andrew; Elefanty, Andrew G.; Stanley, Edouard G.; Greiner, Dale L.; Keller, Gordon

    2015-01-01

    Summary Human pluripotent stem cells (hPSCs) represent a renewable source of pancreatic beta cells for both basic research and therapeutic applications. Given this outstanding potential, significant efforts have been made to identify the signaling pathways that regulate pancreatic development in hPSC differentiation cultures. In this study, we demonstrate that the combination of epidermal growth factor (EGF) and nicotinamide signaling induces the generation of NKX6-1+ progenitors from all hPSC lines tested. Furthermore, we show that the size of the NKX6-1+ population is regulated by the duration of treatment with retinoic acid, fibroblast growth factor 10 (FGF10), and inhibitors of bone morphogenetic protein (BMP) and hedgehog signaling pathways. When transplanted into NOD scid gamma (NSG) recipients, these progenitors differentiate to give rise to exocrine and endocrine cells, including monohormonal insulin+ cells. Together, these findings provide an efficient and reproducible strategy for generating highly enriched populations of hPSC-derived beta cell progenitors for studies aimed at further characterizing their developmental potential in vivo and deciphering the pathways that regulate their maturation in vitro. PMID:25843049

  7. Why do so many petals have conical epidermal cells?

    PubMed Central

    Whitney, Heather M.; Bennett, K. M. Veronica; Dorling, Matthew; Sandbach, Lucy; Prince, David; Chittka, Lars; Glover, Beverley J.

    2011-01-01

    Background The conical epidermal cells found on the petals of most Angiosperm species are so widespread that they have been used as markers of petal identity, but their function has only been analysed in recent years. This review brings together diverse data on the role of these cells in pollination biology. Scope The published effects of conical cells on petal colour, petal reflexing, scent production, petal wettability and pollinator grip on the flower surface are considered. Of these factors, pollinator grip has been shown to be of most significance in the well-studied Antirrhinum majus/bumble-bee system. Published data on the relationship between epidermal cell morphology and floral temperature were limited, so an analysis of the effects of cell shape on floral temperature in Antirrhinum is presented here. Statistically significant warming by conical cells was not detected, although insignificant trends towards faster warming at dawn were found, and it was also found that flat-celled flowers could be warmer on warm days. The warming observed is less significant than that achieved by varying pigment content. However, the possibility that the effect of conical cells on temperature might be biologically significant in certain specific instances such as marginal habitats or weather conditions cannot be ruled out. Conclusions Conical epidermal cells can influence a diverse set of petal properties. The fitness benefits they provide to plants are likely to vary with pollinator and habitat, and models are now required to understand how these different factors interact. PMID:21470973

  8. PW1 gene/paternally expressed gene 3 (PW1/Peg3) identifies multiple adult stem and progenitor cell populations

    PubMed Central

    Besson, Vanessa; Smeriglio, Piera; Wegener, Amélie; Relaix, Frédéric; Nait Oumesmar, Brahim; Sassoon, David A.; Marazzi, Giovanna

    2011-01-01

    A variety of markers are invaluable for identifying and purifying stem/progenitor cells. Here we report the generation of a murine reporter line driven by Pw1 that reveals cycling and quiescent progenitor/stem cells in all adult tissues thus far examined, including the intestine, blood, testis, central nervous system, bone, skeletal muscle, and skin. Neurospheres generated from the adult PW1-reporter mouse show near 100% reporter-gene expression following a single passage. Furthermore, epidermal stem cells can be purified solely on the basis of reporter-gene expression. These cells are clonogenic, repopulate the epidermal stem-cell niches, and give rise to new hair follicles. Finally, we demonstrate that only PW1 reporter-expressing epidermal cells give rise to follicles that are capable of self-renewal following injury. Our data demonstrate that PW1 serves as an invaluable marker for competent self-renewing stem cells in a wide array of adult tissues, and the PW1-reporter mouse serves as a tool for rapid stem cell isolation and characterization. PMID:21709251

  9. Retinal progenitor cells, differentiation, and barriers to cell cycle reentry.

    PubMed

    Davis, Denise M; Dyer, Michael A

    2010-01-01

    Neurogenesis in the retina occurs via the coordination of proliferation, cell cycle exit and differentiation of retinal progenitor cells. Until recently, it was widely assumed that once a retinal progenitor cell produced a postmitotic neuron, there was no possibility for cell-cycle re-entry. However, recent studies have shown that mature differentiated horizontal neurons with reduced Rb pathway function can re-enter the cell cycle and proliferate while maintaining their differentiated features. This chapter will explore the molecular and cellular mechanisms that help to keep differentiated retinal neurons and glia postmitotic. We propose that there are cell-type specific barriers to cell-cycle re-entry by differentiated neurons and these may include apoptosis, chromatin/epigenetics mechanisms, cellular morphology and/or metabolic demands that are distinct across cell populations. Our data suggest that differentiated neurons span a continuum of cellular properties related to their ability to re-enter the cell cycle and undergo cytokinesis while maintaining their differentiated features. A deeper understanding of these processes may allow us to begin to explain the cell type specificity of neuronal cell death and tumor susceptibility. For example, neurons that have more barriers to cell-cycle re-entry may be less likely to form tumors but more likely to undergo degeneration. Conversely, neurons that have fewer barriers to cell-cycle re-entry may be more likely to form tumors but less likely to undergo degeneration. PMID:20959166

  10. Estimating the Size of Onion Epidermal Cells from Diffraction Patterns

    NASA Astrophysics Data System (ADS)

    Groff, Jeffrey R.

    2012-10-01

    Bioscience and premedical profession students are a major demographic served by introductory physics courses at many colleges and universities. Exposing these students to biological applications of physical principles will help them to appreciate physics as a useful tool for their future professions. Here I describe an experiment suitable for introductory physics where principles of wave optics are applied to probe the size of onion epidermal cells. The epidermis tissue is composed of cells of relatively uniform size and shape (Fig. 1) so the tissue acts like a one-dimensional transmission diffraction grating. The diffraction patterns generated when a laser beam passes through the tissue (Fig. 2) are analyzed and an estimate of the average width of individual onion epidermal cells is calculated. The results are compared to direct measurements taken using a light microscope. The use of microscopes and plant-cell tissue slides creates opportunities for cross-discipline collaboration between physics and biology instructors.

  11. Gene expression changes in the course of neural progenitor cell differentiation.

    PubMed

    Gurok, Ulf; Steinhoff, Christine; Lipkowitz, Bettina; Ropers, H-Hilger; Scharff, Constance; Nuber, Ulrike A

    2004-06-30

    The molecular changes underlying neural progenitor differentiation are essentially unknown. We applied cDNA microarrays with 13,627 clones to measure dynamic gene expression changes during the in vitro differentiation of neural progenitor cells that were isolated from the subventricular zone of postnatal day 7 mice and grown in vitro as neurospheres. In two experimental series in which we withdrew epidermal growth factor and added the neurotrophins Neurotrophin-4 or BDNF, four time points were investigated: undifferentiated cells grown as neurospheres, and cells 24, 48, and 96 hr after differentiation. Expression changes of selected genes were confirmed by semiquantitative RT-PCR. Ten different groups of gene expression dynamics obtained by cluster analysis are described. To correlate selected gene expression changes to the localization of respective proteins, we performed immunostainings of cultured neurospheres and of brain sections from adult mice. Our results provide new insights into the genetic program of neural progenitor differentiation and give strong hints to as yet unknown cellular communications within the adult subventricular zone stem cell niche. PMID:15229246

  12. Endothelial Progenitor Cells in Diabetic Retinopathy

    PubMed Central

    Lois, Noemi; McCarter, Rachel V.; O’Neill, Christina; Medina, Reinhold J.; Stitt, Alan W.

    2014-01-01

    Diabetic retinopathy (DR) is a leading cause of visual impairment worldwide. Patients with DR may irreversibly lose sight as a result of the development of diabetic macular edema (DME) and/or proliferative diabetic retinopathy (PDR); retinal blood vessel dysfunction and degeneration plays an essential role in their pathogenesis. Although new treatments have been recently introduced for DME, including intravitreal vascular endothelial growth factor inhibitors (anti-VEGFs) and steroids, a high proportion of patients (~40–50%) do not respond to these therapies. Furthermore, for people with PDR, laser photocoagulation remains a mainstay therapy despite this being an inherently destructive procedure. Endothelial progenitor cells (EPCs) are a low-frequency population of circulating cells known to be recruited to sites of vessel damage and tissue ischemia where they promote vascular healing and re-perfusion. A growing body of evidence suggests that the number and function of EPCs are altered in patients with varying degrees of diabetes duration, metabolic control, and in the presence or absence of DR. Although there are no clear-cut outcomes from these clinical studies, there is mounting evidence that some EPC sub-types may be involved in the pathogenesis of DR and may also serve as biomarkers for disease progression and stratification. Moreover, some EPC sub-types have considerable potential as therapeutic modalities for DME and PDR in the context of cell therapy. This study presents basic clinical concepts of DR and combines this with a general insight on EPCs and their relation to future directions in understanding and treating this important diabetic complication. PMID:24782825

  13. Stem and progenitor cell dysfunction in human trisomies

    PubMed Central

    Liu, Binbin; Filippi, Sarah; Roy, Anindita; Roberts, Irene

    2015-01-01

    Trisomy 21, the commonest constitutional aneuploidy in humans, causes profound perturbation of stem and progenitor cell growth, which is both cell context dependent and developmental stage specific and mediated by complex genetic mechanisms beyond increased Hsa21 gene dosage. While proliferation of fetal hematopoietic and testicular stem/progenitors is increased and may underlie increased susceptibility to childhood leukemia and testicular cancer, fetal stem/progenitor proliferation in other tissues is markedly impaired leading to the characteristic craniofacial, neurocognitive and cardiac features in individuals with Down syndrome. After birth, trisomy 21-mediated premature aging of stem/progenitor cells may contribute to the progressive multi-system deterioration, including development of Alzheimer's disease. PMID:25520324

  14. Myogenic Progenitors from Mouse Pluripotent Stem Cells for Muscle Regeneration.

    PubMed

    Magli, Alessandro; Incitti, Tania; Perlingeiro, Rita C R

    2016-01-01

    Muscle homeostasis is maintained by resident stem cells which, in both pathologic and non-pathologic conditions, are able to repair or generate new muscle fibers. Although muscle stem cells have tremendous regenerative potential, their application in cell therapy protocols is prevented by several restrictions, including the limited ability to grow ex vivo. Since pluripotent stem cells have the unique potential to both self-renew and expand almost indefinitely, they have become an attractive source of progenitors for regenerative medicine studies. Our lab has demonstrated that embryonic stem cell (ES)-derived myogenic progenitors retain the ability to repair existing muscle fibers and contribute to the pool of resident stem cells. Because of their relevance in both cell therapy and disease modeling, in this chapter we describe the protocol to derive myogenic progenitors from murine ES cells followed by their intramuscular delivery in a murine muscular dystrophy model. PMID:27492174

  15. Zebrafish grainyhead-like1 is a common marker of different non-keratinocyte epidermal cell lineages, which segregate from each other in a Foxi3-dependent manner

    PubMed Central

    JÄNICKE, MARTINA; RENISCH, BJÖRN; HAMMERSCHMIDT, MATTHIAS

    2012-01-01

    Grainyhead/CP2 transcription factor family members are widely conserved among the animal kingdom and have been implicated in different developmental processes. Thus far, nothing has been known about their roles in zebrafish. Here we identify seven zebrafish grainyhead-like (grhl) / cp2 genes, with focus on grhl1, which is expressed in the periderm and in epidermal ionocyte progenitors, but downregulated when ionocytes differentiate. In addition, expression was detected in other “non-keratinocyte” cell types of the epidermis, such as pvalb8-expressing cells, which according to our lineage tracing experiments are derived from the same pool of progenitor cells like keratinocytes and ionocytes. Antisense morpholino oligonucleotide-based loss-of-function analysis revealed that grhl1 is dispensable for the development and function of all investigated epidermal cell types, but required as a negative regulator of its own transcription during ionocyte differentiation. Knockdown of the transcription factor Foxi3a, which is expressed in a subset of the grhl1 population, caused a loss of ionocytes and a corresponding increase in the number of pvalb8-expressing cells, while leaving the number of grhl1-positive cells unaltered. We propose that grhl1 is a novel common marker of all or most “non-keratinocyte” epidermal progenitors, and that the sub-functionalisation of these cells is regulated by differential positive and negative effects of Foxi3 factors. PMID:19757382

  16. Development and molecular composition of the hepatic progenitor cell niche.

    PubMed

    Vestentoft, Peter Siig

    2013-05-01

    End-stage liver diseases represent major health problems that are currently treated by liver transplantation. However, given the world-wide shortage of donor livers novel strategies are needed for therapeutic treatment. Adult stem cells have the ability to self-renew and differentiate into the more specialized cell types of a given organ and are found in tissues throughout the body. These cells, whose progeny are termed progenitor cells in human liver and oval cells in rodents, have the potential to treat patients through the generation of hepatic parenchymal cells, even from the patient's own tissue. Little is known regarding the nature of the hepatic progenitor cells. Though they are suggested to reside in the most distal part of the biliary tree, the canal of Hering, the lack of unique surface markers for these cells has hindered their isolation and characterization. Upon activation, they proliferate and form ductular structures, termed "ductular reactions", which radiate into the hepatic parenchyma. The ductular reactions contain activated progenitor cells that not only acquire a phenotype resembling that observed in developing liver but also display markers of differentiation shared with the cholangiocytic or hepatocytic lineages, the two parenchymal hepatic cell types. Interactions between the putative progenitor cells, the surrounding support cells and the extracellular matrix scaffold, all constituting the progenitor cell niche, are likely to be important for regulating progenitor cell activity and differentiation. Therefore, identifying novel progenitor cell markers and deciphering their microenvironment could facilitate clinical use. The aims of the present PhD thesis were to expand knowledge of the hepatic progenitor cell niche and characterize it both during development and in disease. Several animal models of hepatic injury are known to induce activation of the progenitor cells. In order to identify possible progenitor cell markers and niche components

  17. Circulating Hematopoietic Progenitor Cells are Decreased in COPD

    PubMed Central

    Janssen, William J.; Yunt, Zulma X.; Muldrow, Alaina; Kearns, Mark T.; Kloepfer, Angela; Barthel, Lea; Bratton, Donna L.; Bowler, Russell P.; Henson, Peter M.

    2014-01-01

    Rationale Bone marrow derived progenitor cells participate in the repair of injured vessels. The lungs of individuals with emphysema have reduced alveolar capillary density and increased endothelial apoptosis. We hypothesized that circulating levels of endothelial and hematopoietic progenitor cells would be reduced in this group of patients. Objectives The goal of this study was to measure circulating levels of endothelial progenitor cells (EPCs) and hematopoietic progenitor cells (HPCs) in subjects with COPD and to determine if progenitor levels correlated with disease severity and the presence of emphysema. Methods Peripheral blood mononuclear cells were isolated from 61 patients with COPD and 32 control subjects. Levels of EPCs (CD45dim CD34+ ) and HPCs (CD45+ CD34+ VEGF-R2+) were quantified using multi-parameter flow cytometry. Progenitor cell function was assessed using cell culture assays. All subjects were evaluated with spirometry and CT scanning. Measurements and Main Results HPC levels were reduced in subjects with COPD compared to controls, whereas circulating EPC levels were similar between the two groups. HPC levels correlated with severity of obstruction and were lowest in subjects with severe emphysema. These associations remained after correction for factors known to affect progenitor cell levels including age, smoking status, the use of statin medications and the presence of coronary artery disease. The ability of mononuclear cells to form endothelial cell colony forming units (EC-CFU) was also reduced in subjects with COPD. Conclusions HPC levels are reduced in subjects with COPD and correlate with emphysema phenotype and severity of obstruction. Reduction of HPCs may disrupt maintenance of the capillary endothelium, thereby contributing to the pathogenesis of COPD. PMID:24182349

  18. Hepatic cancer stem cells may arise from adult ductal progenitors

    PubMed Central

    Nikolaou, Kostas C; Talianidis, Iannis

    2016-01-01

    Cancer stem cells (CSCs) are defined as cells within tumors that can self-renew and differentiate into heterogeneous lineages of cancerous cells. The origin of CSCs is not well understood. Recent evidence suggests that CSCs in hepatocellular carcinoma could be generated via oncogenic transformation and partial differentiation of adult hepatic ductal progenitor cells.

  19. Signaling pathways implicated in hematopoietic progenitor cell proliferation and differentiation.

    PubMed

    Bugarski, Diana; Krstic, Aleksandra; Mojsilovic, Slavko; Vlaski, Marija; Petakov, Marijana; Jovcic, Gordana; Stojanovic, Nevenka; Milenkovic, Pavle

    2007-01-01

    The objective of this study was to investigate the signal transduction pathways associated with the clonal development of myeloid and erythroid progenitor cells. The contribution of particular signaling molecules of protein tyrosine kinases (PTKs), mitogen-activated protein (MAP) kinase, and PI-3 kinase signaling to the growth of murine bone marrow colony forming unit-granulocyte-macrophage (CFU-GM) and erythroid (burst forming unit-erythroid [BFU-E] and colony forming unit-erythroid [CFU-E]) progenitors was examined in studies performed in the presence or absence of specific signal transduction inhibitors. The results clearly pointed to different signal transducing intermediates that are involved in cell proliferation and differentiation depending on the cell lineage, as well as on the progenitors' maturity. Lineage-specific differences were obtained when chemical inhibitors specific for receptor- or nonreceptor-PTKs, as well as for the main groups of distinctly regulated MAPK cascades, were used because all of these compounds suppressed the growth of erythroid progenitors, with no major effects on myeloid progenitors. At the same time, differential involvement of MEK/extracellular signal-regulated kinase (ERK) MAPK transduction pathway was observed in the proliferation and/or differentiation of early, BFU-E, and late, CFU-E, erythroid progenitor cells. The results also demonstrated that phosphatydylinositol (PI)-3 kinase and nuclear factor kappaB (NF-kappaB) transcriptional factor were required for maintenance of both myeloid and erythroid progenitor cell function. Overall, the data obtained indicated that committed hematopoietic progenitors express a certain level of constitutive signaling activity that participates in the regulation of normal steady-state hematopoiesis and point to the importance of evaluating the impact of signal transduction inhibitors on normal bone marrow when used as potential therapeutic agents. PMID:17202596

  20. Murine Hematopoietic Stem cells and Progenitors Express Adrenergic Receptors

    PubMed Central

    Muthu, Kuzhali; Iyer, Sivaraman; He, L-K.; Szilagyi, Andrea; Gamelli, Richard L; Shankar, Ravi; Jones, Stephen B

    2007-01-01

    Association between the nervous and immune system is well documented. Immune cells originate within the bone marrow that is innervated. Thermal injury induces adrenergic stimulation, augments monocytopoiesis and alters the β-adrenergic receptor (AR) profile of bone marrow monocyte committed progenitors. This provides an impetus to study AR expression in hematopoietic progenitors along myeloid lineage. Using FACS analysis and confocal microscopy, we report the expression of α1-, α2- and β2- AR in enriched populations of ER-MP20+ and ER-MP12+ myeloid progenitors, CD117+ and CD34+ multi-potential progenitors and more importantly pluripotent stem cells suggesting a plausible role for catecholamine in hematopoietic development. PMID:17428548

  1. Endothelial progenitor cells in acute ischemic stroke

    PubMed Central

    Martí-Fàbregas, Joan; Crespo, Javier; Delgado-Mederos, Raquel; Martínez-Ramírez, Sergi; Peña, Esther; Marín, Rebeca; Dinia, Lavinia; Jiménez-Xarrié, Elena; Fernández-Arcos, Ana; Pérez-Pérez, Jesús; Querol, Luis; Suárez-Calvet, Marc; Badimon, Lina

    2013-01-01

    Objectives The levels of circulating endothelial progenitor cells (EPCs) in ischemic stroke have not been studied extensively and reported results are inconsistent. We aimed to investigate the time course, the prognostic relevance, and the variables associated with EPC counts in patients with ischemic stroke at different time points. Material and methods We studied prospectively 146 consecutive patients with ischemic stroke within the first 48 h from the onset of symptoms (baseline). We evaluated demographic data, classical vascular risk factors, treatment with thrombolysis and statins, stroke etiology, National Institute of Health and Stroke Scale score and outcome (favorable when Rankin scale score 0–2). Blood samples were collected at baseline, at day 7 after stroke (n = 121) and at 3 months (n = 92). The EPC were measured by flow cytometry. Results We included 146 patients with a mean age of 70.8 ± 12.2 years. The circulating EPC levels were higher on day 7 than at baseline or at 3 months (P = 0.045). Pretreatment with statins (odds ratio [OR] 3.11, P = 0.008) and stroke etiology (P = 0.032) were predictive of EPC counts in the baseline sample. EPC counts were not associated with stroke severity or functional outcome in all the patients. However, using multivariate analyses, a better functional outcome was found in patients with higher EPC counts in large-artery atherosclerosis and small-vessel disease etiologic subtypes. Conclusions After acute ischemic stroke, circulating EPC counts peaked at day 7. Pretreatment with statins increased the levels of EPC. In patients with large-artery atherosclerosis and small-vessel disease subtypes, higher counts were related to better outcome at 3 months. PMID:24363968

  2. Spatiotemporal coordination of stem cell commitment during epidermal homeostasis.

    PubMed

    Rompolas, Panteleimon; Mesa, Kailin R; Kawaguchi, Kyogo; Park, Sangbum; Gonzalez, David; Brown, Samara; Boucher, Jonathan; Klein, Allon M; Greco, Valentina

    2016-06-17

    Adult tissues replace lost cells via pools of stem cells. However, the mechanisms of cell self-renewal, commitment, and functional integration into the tissue remain unsolved. Using imaging techniques in live mice, we captured the lifetime of individual cells in the ear and paw epidermis. Our data suggest that epidermal stem cells have equal potential to either divide or directly differentiate. Tracking stem cells over multiple generations reveals that cell behavior is not coordinated between generations. However, sibling cell fate and lifetimes are coupled. We did not observe regulated asymmetric cell divisions. Lastly, we demonstrated that differentiating stem cells integrate into preexisting ordered spatial units of the epidermis. This study elucidates how a tissue is maintained by both temporal and spatial coordination of stem cell behaviors. PMID:27229141

  3. Spatiotemporal coordination of stem cell commitment during epidermal homeostasis

    PubMed Central

    Rompolas, Panteleimon; Mesa, Kailin R.; Kawaguchi, Kyogo; Park, Sangbum; Gonzalez, David; Brown, Samara; Boucher, Jonathan; Klein, Allon M.; Greco, Valentina

    2016-01-01

    Adult tissues replace lost cells via pools of stem cells. However, the mechanisms of cell self-renewal, commitment, and functional integration into the tissue remain unsolved. Using imaging techniques in live mice, we captured the lifetime of individual cells in the ear and paw epidermis. Our data suggest that epidermal stem cells have equal potential to either divide or directly differentiate. Tracking stem cells over multiple generations reveals that cell behavior is not coordinated between generations. However, sibling cell fate and lifetimes are coupled. We did not observe regulated asymmetric cell divisions. Lastly, we demonstrated that differentiating stem cells integrate into preexisting ordered spatial units of the epidermis. This study elucidates how a tissue is maintained by both temporal and spatial coordination of stem cell behaviors. PMID:27229141

  4. Simultaneous characterization of progenitor cell compartments in adult human liver.

    PubMed

    Porretti, Laura; Cattaneo, Alessandra; Colombo, Federico; Lopa, Raffaella; Rossi, Giorgio; Mazzaferro, Vincenzo; Battiston, Carlo; Svegliati-Baroni, Gianluca; Bertolini, Francesco; Rebulla, Paolo; Prati, Daniele

    2010-01-01

    The human liver is a complex tissue consisting of epithelial, endothelial, hematopoietic, and mesenchymal elements that probably derive from multiple lineage-committed progenitors, but no comprehensive study aimed at identifying and characterizing intrahepatic precursors has yet been published. Cell suspensions for this study were obtained by enzymatic digestion of liver specimens taken from 20 patients with chronic liver disease and 13 multiorgan donors. Stem and progenitor cells were first isolated, amplified, and characterized ex vivo according to previously validated methods, and then optimized flow cytometry was used to assess their relative frequencies and characterize their immunophenotypes in the clinical specimens. Stem and progenitor cells committed to hematopoietic, endothelial, epithelial, and mesenchymal lineages were clearly identifiable in livers from both healthy and diseased subjects. Within the mononuclear liver cell compartment, epithelial progenitors [epithelial cell adhesion molecule (EpCAM)(+)/CD49f(+)/CD29(+)/CD45(-)] accounted for 2.7-3.5% whereas hematopoietic (CD34(+)/CD45(+)), endothelial [vascular endothelial growth factor-2 (KDR)(+)/CD146(+)/CD45(-)], and mesenchymal [CD73(+)/CD105(+)/CD90 (Thy-1)(+)/CD45 (-)] stem cells and progenitors accounted for smaller fractions (0.02-0.6%). The patients' livers had higher percentages of hematopoietic and endothelial precursors than those of the donors. In conclusion, we identified and characterized precursors committed to four different lineages in adult human liver. We also optimized a flow cytometry approach that will be useful in exploring the contribution of these cells to the pathogenesis of liver disease. PMID:19960544

  5. Inhibition of cyclooxygenase (COX)-2 affects endothelial progenitor cell proliferation

    SciTech Connect

    Colleselli, Daniela; Bijuklic, Klaudija; Mosheimer, Birgit A.; Kaehler, Christian M. . E-mail: C.M.Kaehler@uibk.ac.at

    2006-09-10

    Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis. Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.

  6. Adipose Tissue Residing Progenitors (Adipocyte Lineage Progenitors and Adipose Derived Stem Cells (ADSC)

    PubMed Central

    Berry, Ryan; Rodeheffer, Matthew S.; Rosen, Clifford J.; Horowitz, Mark C.

    2015-01-01

    The formation of brown, white and beige adipocytes have been a subject of intense scientific interest in recent years due to the growing obesity epidemic in the United States and around the world. This interest has led to the identification and characterization of specific tissue resident progenitor cells that give rise to each adipocyte population in vivo. However, much still remains to be discovered about each progenitor population in terms of their “niche” within each tissue and how they are regulated at the cellular and molecular level during healthy and diseased states. While our knowledge of brown, white and beige adipose tissue is rapidly increasing, little is still known about marrow adipose tissue and its progenitor despite recent studies demonstrating possible roles for marrow adipose tissue in regulating the hematopoietic space and systemic metabolism at large. This chapter focuses on our current knowledge of brown, white, beige and marrow adipose tissue with a specific focus on the formation of each tissue from tissue resident progenitor cells. PMID:26526875

  7. Heterogeneity and plasticity of epidermal stem cells

    PubMed Central

    Schepeler, Troels; Page, Mahalia E.; Jensen, Kim B.

    2014-01-01

    The epidermis is an integral part of our largest organ, the skin, and protects us against the hostile environment. It is a highly dynamic tissue that, during normal steady-state conditions, undergoes constant turnover. Multiple stem cell populations residing in autonomously maintained compartments facilitate this task. In this Review, we discuss stem cell behaviour during normal tissue homeostasis, regeneration and disease within the pilosebaceous unit, an integral structure of the epidermis that is responsible for hair growth and lubrication of the epithelium. We provide an up-to-date view of the pilosebaceous unit, encompassing the heterogeneity and plasticity of multiple discrete stem cell populations that are strongly influenced by external cues to maintain their identity and function. PMID:24961797

  8. Endometrial stem/progenitor cells: the first 10 years

    PubMed Central

    Gargett, Caroline E.; Schwab, Kjiana E.; Deane, James A.

    2016-01-01

    BACKGROUND The existence of stem/progenitor cells in the endometrium was postulated many years ago, but the first functional evidence was only published in 2004. The identification of rare epithelial and stromal populations of clonogenic cells in human endometrium has opened an active area of research on endometrial stem/progenitor cells in the subsequent 10 years. METHODS The published literature was searched using the PubMed database with the search terms ‘endometrial stem cells and menstrual blood stem cells' until December 2014. RESULTS Endometrial epithelial stem/progenitor cells have been identified as clonogenic cells in human and as label-retaining or CD44+ cells in mouse endometrium, but their characterization has been modest. In contrast, endometrial mesenchymal stem/stromal cells (MSCs) have been well characterized and show similar properties to bone marrow MSCs. Specific markers for their enrichment have been identified, CD146+PDGFRβ+ (platelet-derived growth factor receptor beta) and SUSD2+ (sushi domain containing-2), which detected their perivascular location and likely pericyte identity in endometrial basalis and functionalis vessels. Transcriptomics and secretomics of SUSD2+ cells confirm their perivascular phenotype. Stromal fibroblasts cultured from endometrial tissue or menstrual blood also have some MSC characteristics and demonstrate broad multilineage differentiation potential for mesodermal, endodermal and ectodermal lineages, indicating their plasticity. Side population (SP) cells are a mixed population, although predominantly vascular cells, which exhibit adult stem cell properties, including tissue reconstitution. There is some evidence that bone marrow cells contribute a small population of endometrial epithelial and stromal cells. The discovery of specific markers for endometrial stem/progenitor cells has enabled the examination of their role in endometrial proliferative disorders, including endometriosis, adenomyosis and Asherman

  9. Impaired DNA replication within progenitor cell pools promotes leukemogenesis.

    PubMed

    Bilousova, Ganna; Marusyk, Andriy; Porter, Christopher C; Cardiff, Robert D; DeGregori, James

    2005-12-01

    Impaired cell cycle progression can be paradoxically associated with increased rates of malignancies. Using retroviral transduction of bone marrow progenitors followed by transplantation into mice, we demonstrate that inhibition of hematopoietic progenitor cell proliferation impairs competition, promoting the expansion of progenitors that acquire oncogenic mutations which restore cell cycle progression. Conditions that impair DNA replication dramatically enhance the proliferative advantage provided by the expression of Bcr-Abl or mutant p53, which provide no apparent competitive advantage under conditions of healthy replication. Furthermore, for the Bcr-Abl oncogene the competitive advantage in contexts of impaired DNA replication dramatically increases leukemogenesis. Impaired replication within hematopoietic progenitor cell pools can select for oncogenic events and thereby promote leukemia, demonstrating the importance of replicative competence in the prevention of tumorigenesis. The demonstration that replication-impaired, poorly competitive progenitor cell pools can promote tumorigenesis provides a new rationale for links between tumorigenesis and common human conditions of impaired DNA replication such as dietary folate deficiency, chemotherapeutics targeting dNTP synthesis, and polymorphisms in genes important for DNA metabolism. PMID:16277552

  10. Erythropoietin guides multipotent hematopoietic progenitor cells toward an erythroid fate

    PubMed Central

    Grover, Amit; Mancini, Elena; Moore, Susan; Mead, Adam J.; Atkinson, Deborah; Rasmussen, Kasper D.; O’Carroll, Donal; Jacobsen, Sten Eirik W.

    2014-01-01

    The erythroid stress cytokine erythropoietin (Epo) supports the development of committed erythroid progenitors, but its ability to act on upstream, multipotent cells remains to be established. We observe that high systemic levels of Epo reprogram the transcriptomes of multi- and bipotent hematopoietic stem/progenitor cells in vivo. This induces erythroid lineage bias at all lineage bifurcations known to exist between hematopoietic stem cells (HSCs) and committed erythroid progenitors, leading to increased erythroid and decreased myeloid HSC output. Epo, therefore, has a lineage instructive role in vivo, through suppression of non-erythroid fate options, demonstrating the ability of a cytokine to systematically bias successive lineage choices in favor of the generation of a specific cell type. PMID:24493804

  11. aPKCλ controls epidermal homeostasis and stem cell fate through regulation of division orientation

    PubMed Central

    Niessen, Michaela T.; Scott, Jeanie; Zielinski, Julia G.; Vorhagen, Susanne; Sotiropoulou, Panagiota A.; Blanpain, Cédric

    2013-01-01

    The atypical protein kinase C (aPKC) is a key regulator of polarity and cell fate in lower organisms. However, whether mammalian aPKCs control stem cells and fate in vivo is not known. Here we show that loss of aPKCλ in a self-renewing epithelium, the epidermis, disturbed tissue homeostasis, differentiation, and stem cell dynamics, causing progressive changes in this tissue. This was accompanied by a gradual loss of quiescent hair follicle bulge stem cells and a temporary increase in proliferating progenitors. Lineage tracing analysis showed that loss of aPKCλ altered the fate of lower bulge/hair germ stem cells. This ultimately led to loss of proliferative potential, stem cell exhaustion, alopecia, and premature aging. Inactivation of aPKCλ produced more asymmetric divisions in different compartments, including the bulge. Thus, aPKCλ is crucial for homeostasis of self-renewing stratifying epithelia, and for the regulation of cell fate, differentiation, and maintenance of epidermal bulge stem cells likely through its role in balancing symmetric and asymmetric division. PMID:24019538

  12. aPKCλ controls epidermal homeostasis and stem cell fate through regulation of division orientation.

    PubMed

    Niessen, Michaela T; Scott, Jeanie; Zielinski, Julia G; Vorhagen, Susanne; Sotiropoulou, Panagiota A; Blanpain, Cédric; Leitges, Michael; Niessen, Carien M

    2013-09-16

    The atypical protein kinase C (aPKC) is a key regulator of polarity and cell fate in lower organisms. However, whether mammalian aPKCs control stem cells and fate in vivo is not known. Here we show that loss of aPKCλ in a self-renewing epithelium, the epidermis, disturbed tissue homeostasis, differentiation, and stem cell dynamics, causing progressive changes in this tissue. This was accompanied by a gradual loss of quiescent hair follicle bulge stem cells and a temporary increase in proliferating progenitors. Lineage tracing analysis showed that loss of aPKCλ altered the fate of lower bulge/hair germ stem cells. This ultimately led to loss of proliferative potential, stem cell exhaustion, alopecia, and premature aging. Inactivation of aPKCλ produced more asymmetric divisions in different compartments, including the bulge. Thus, aPKCλ is crucial for homeostasis of self-renewing stratifying epithelia, and for the regulation of cell fate, differentiation, and maintenance of epidermal bulge stem cells likely through its role in balancing symmetric and asymmetric division. PMID:24019538

  13. Epithelial Sodium Channels in Pulmonary Epithelial Progenitor and Stem Cells

    PubMed Central

    Liu, Yang; Jiang, Bi-Jie; Zhao, Run-Zhen; Ji, Hong-Long

    2016-01-01

    Regeneration of the epithelium of mammalian lungs is essential for restoring normal function following injury, and various cells and mechanisms contribute to this regeneration and repair. Club cells, bronchioalveolar stem cells (BASCs), and alveolar type II epithelial cells (ATII) are dominant stem/progenitor cells for maintaining epithelial turnover and repair. Epithelial Na+ channels (ENaC), a critical pathway for transapical salt and fluid transport, are expressed in lung epithelial progenitors, including club and ATII cells. Since ENaC activity and expression are development- and differentiation-dependent, apically located ENaC activity has therefore been used as a functional biomarker of lung injury repair. ENaC activity may be involved in the migration and differentiation of local and circulating stem/progenitor cells with diverse functions, eventually benefiting stem cells spreading to re-epithelialize injured lungs. This review summarizes the potential roles of ENaC expressed in native progenitor and stem cells in the development and regeneration of the respiratory epithelium. PMID:27570489

  14. The Mammary Gland Microenvironment Directs Progenitor Cell Fate In Vivo

    PubMed Central

    Bussard, Karen M.; Smith, Gilbert H.

    2011-01-01

    The mammary gland is a unique organ that continually undergoes postnatal developmental changes. In mice, the mammary gland is formed via signals from terminal end buds, which direct ductal growth and elongation. Intriguingly, it is likely that the entire cellular repertoire of the mammary gland is formed from a single antecedent cell. Furthermore, in order to produce progeny of varied lineages (e.g., luminal and myoepithelial cells), signals from the local tissue microenvironment influence mammary stem/progenitor cell fate. Data have shown that cells from the mammary gland microenvironment reprogram adult somatic cells from other organs (testes, nerve) into cells that produce milk and express mammary epithelial cell proteins. Similar results were found for human tumorigenic epithelial carcinoma cells. Presently, it is unclear how the deterministic power of the mammary gland microenvironment controls epithelial cell fate. Regardless, signals generated by the microenvironment have a profound influence on progenitor cell differentiation in vivo. PMID:21647291

  15. Effects of Nitrogen on Mesophyll Cell Division and Epidermal Cell Elongation in Tall Fescue Leaf Blades 1

    PubMed Central

    MacAdam, Jennifer W.; Volenec, Jeffrey J.; Nelson, Curtis J.

    1989-01-01

    Leaf elongation rate (LER) in grasses is dependent on epidermal cell supply (number) and on rate and duration of epidermal cell elongation. Nitrogen (N) fertilization increases LER. Longitudinal sections from two genotypes of tall fescue (Festuca arundinacea Schreb.), which differ by 50% in LER, were used to quantify the effects of N on the components of epidermal cell elongation and on mesophyll cell division. Rate and duration of epidermal cell elongation were determined by using a relationship between cell length and displacement velocity derived from the continuity equation. Rate of epidermal cell elongation was exponential. Relative rates of epidermal cell elongation increased by 9% with high N, even though high N increased LER by 89%. Duration of cell elongation was approximately 20 h longer in the high- than in the low-LER genotype regardless of N treatment. The percentage of mesophyll cells in division was greater in the high- than in the low-LER genotype. This increased with high N in both genotypes, indicating that LER increased with cell supply. Division of mesophyll cells adjacent to abaxial epidermal cells continued after epidermal cell division stopped, until epidermal cells had elongated to a mean length of 40 micrometers in the high-LER and a mean length of 50 micrometers in the low-LER genotype. The cell cycle length for mesophyll cells was calculated to be 12 to 13 hours. Nitrogen increased mesophyll cell number more than epidermal cell number: in both genotypes, the final number of mesophyll cells adjacent to each abaxial epidermal cell was 10 with low N and 14 with high N. A spatial model is used to describe three cell development processes relevant to leaf growth. It illustrates the overlap of mesophyll cell division and epidermal cell elongation, and the transition from epidermal cell elongation to secondary cell wall deposition. PMID:16666581

  16. Osteocytes serve as a progenitor cell of osteosarcoma

    PubMed Central

    Sottnik, Joseph L; Campbell, Brittany; Mehra, Rohit; Behbahani-Nejad, Omid; Hall, Christopher L.; Keller, Evan T.

    2016-01-01

    Osteosarcoma (OSA) is the most common primary bone tumor in humans. However, the cell of origin of OSA is not clearly defined although there is evidence that osteoblasts may serve as OSA progenitors. The role of osteocytes, terminally differentiated osteoblasts, as OSA progenitors has yet to be described. Analysis of patient cDNA from publicly available microarray data revealed that patients with OSA have increased expression of dentin matrix phosphoprotein 1 (DMP1), a marker of osteocytes. Analysis of multiple murine, human, and canine OSA cell lines revealed DMP1 expression. To test the tumorigenic potential of osteocytes, MLO-Y4, an SV-40 immortalized murine osteocyte cell line, was injected into subcutaneous and orthotopic (intratibial) sites of mice. Tumor growth occurred in both locations. Orthotopic MLO-Y4 tumors produced mixed osteoblastic/osteolytic radiographic lesions; a hallmark of OSA. Together, these data demonstrate for the first time that osteocytes can serve as OSA progenitors. PMID:24700678

  17. Osteocytes serve as a progenitor cell of osteosarcoma.

    PubMed

    Sottnik, Joseph L; Campbell, Brittany; Mehra, Rohit; Behbahani-Nejad, Omid; Hall, Christopher L; Keller, Evan T

    2014-08-01

    Osteosarcoma (OSA) is the most common primary bone tumor in humans. However, the cell of origin of OSA is not clearly defined although there is evidence that osteoblasts may serve as OSA progenitors. The role of osteocytes, terminally differentiated osteoblasts, as OSA progenitors has yet to be described. Analysis of patient cDNA from publicly available microarray data revealed that patients with OSA have increased expression of dentin matrix phosphoprotein 1 (DMP1), a marker of osteocytes. Analysis of multiple murine, human, and canine OSA cell lines revealed DMP1 expression. To test the tumorigenic potential of osteocytes, MLO-Y4, a SV-40 immortalized murine osteocyte cell line, was injected into subcutaneous and orthotopic (intratibial) sites of mice. Tumor growth occurred in both locations. Orthotopic MLO-Y4 tumors produced mixed osteoblastic/osteolytic radiographic lesions; a hallmark of OSA. Together, these data demonstrate for the first time that osteocytes can serve as OSA progenitors. PMID:24700678

  18. Endothelial progenitor cells and burn injury - exploring the relationship.

    PubMed

    Banyard, Derek A; Adnani, Blake O; Melkumyan, Satenik; Araniego, Cheryl Ann; Widgerow, Alan D

    2016-01-01

    Burn wounds result in varying degrees of soft tissue damage that are typically graded clinically. Recently a key participant in neovascularization, the endothelial progenitor cell, has been the subject of intense cardiovascular research to explore whether it can serve as a biomarker for vascular injury. In this review, we examine the identity of the endothelial progenitor cell as well as the evidence that support its role as a key responder after burn insult. While there is conflicting evidence with regards to the delta of endothelial progenitor cell mobilization and burn severity, it is clear that they play an important role in wound healing. Systematic and controlled studies are needed to clarify this relationship, and whether this population can serve as a biomarker for burn severity. PMID:27574674

  19. Multipotent progenitor cells isolated from adult human pancreatic tissue.

    PubMed

    Todorov, I; Nair, I; Ferreri, K; Rawson, J; Kuroda, A; Pascual, M; Omori, K; Valiente, L; Orr, C; Al-Abdullah, I; Riggs, A; Kandeel, F; Mullen, Y

    2005-10-01

    The supply of islet cells is a limiting factor for the widespread application of islet transplantation of type-1 diabetes. Islets constitute 1% to 2% of pancreatic tissue, leaving approximately 98% as discard after islet isolation and purification. In this report we present our data on the isolation of multipotent progenitor cells from discarded adult human pancreatic tissue. The collected cells from discarded nonislet fractions, after enzymatic digestion and gradient purification of islets, were dissociated for suspension culture in a serum-free medium. The cell clusters grown to a size of 100 to 150 mum contained cells staining for stage-specific embryonic antigens, but not insulin or C-peptide. To direct cell differentiation toward islets, clusters were recultured in a pancreatic differentiation medium. Insulin and C-peptide-positive cells by immunocytochemistry appeared within a week, reaching over 10% of the cell population. Glucagon and somatostatin-positive cells were also detected. The cell clusters were found to secrete insulin in response to glucose stimulation. Cells from the same clusters also had the capacity for differentiation into neural cells, as documented by staining for neural and glial cell markers when cultured as monolayers in media containing neurotrophic factors. These data suggest that multipotent pancreatic progenitor cells exist within the human pancreatic tissue that is typically discarded during islet isolation procedures. These adult progenitor cells can be successfully differentiated into insulin-producing cells, and thus they have the potential for treatment of type-1 diabetes mellitus. PMID:16298614

  20. Neural stem and progenitor cells in health and disease

    PubMed Central

    Ladran, Ian; Tran, Ngoc; Topol, Aaron; Brennand, Kristen J.

    2014-01-01

    Neural stem/progenitor cells (NSPCs) have the potential to differentiate into neurons, astrocytes, and/or oligodendrocytes. Because these cells can be expanded in culture, they represent a vast source of neural cells. With the recent discovery that patient fibroblasts can be reprogrammed directly into induced NSPCs, the regulation of NSPC fate and function, in the context of cell-based disease models and patient-specific cell-replacement therapies, warrants review. PMID:24068527

  1. Recent advances in cancer stem/progenitor cell research: therapeutic implications for overcoming resistance to the most aggressive cancers.

    PubMed

    Mimeault, M; Hauke, R; Mehta, P P; Batra, S K

    2007-01-01

    Overcoming intrinsic and acquired resistance of cancer stem/progenitor cells to current clinical treatments represents a major challenge in treating and curing the most aggressive and metastatic cancers. This review summarizes recent advances in our understanding of the cellular origin and molecular mechanisms at the basis of cancer initiation and progression as well as the heterogeneity of cancers arising from the malignant transformation of adult stem/progenitor cells. We describe the critical functions provided by several growth factor cascades, including epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR), stem cell factor (SCF) receptor (KIT), hedgehog and Wnt/beta-catenin signalling pathways that are frequently activated in cancer progenitor cells and are involved in their sustained growth, survival, invasion and drug resistance. Of therapeutic interest, we also discuss recent progress in the development of new drug combinations to treat the highly aggressive and metastatic cancers including refractory/relapsed leukaemias, melanoma and head and neck, brain, lung, breast, ovary, prostate, pancreas and gastrointestinal cancers which remain incurable in the clinics. The emphasis is on new therapeutic strategies consisting of molecular targeting of distinct oncogenic signalling elements activated in the cancer progenitor cells and their local microenvironment during cancer progression. These new targeted therapies should improve the efficacy of current therapeutic treatments against aggressive cancers, and thereby preventing disease relapse and enhancing patient survival. PMID:17979879

  2. Characterization of reversibly immortalized calvarial mesenchymal progenitor cells

    PubMed Central

    Shenaq, Deana S.; Teven, Chad M.; Seitz, Iris A.; Rastegar, Farbod; Greives, Matthew R.; He, Tong-Chuan; Reid, Russell R.

    2015-01-01

    Background Bone morphogenetic proteins (BMPs) play a sentinel role in osteoblastic differentiation, and their implementation into clinical practice can revolutionize cranial reconstruction. Preliminary data suggest a therapeutic role of adenoviral gene delivery of BMPs in murine calvarial defect healing. Poor transgene expression inherent in direct adenoviral therapy prompted investigation of cell-based strategies. Objective To isolate and immortalize calvarial cells as a potential progenitor source for osseous tissue engineering. Materials & Methods Cells were isolated from murine skulls, cultured, and transduced with a retroviral vector bearing the loxP-flanked SV40 large T antigen. Immortalized calvarial cells (iCALs) were evaluated via light microscopy, immunohistochemistry, and flow cytometry to determine whether the immortalization process altered cell morphology or progenitor cell profile. iCALs were then infected with adenoviral vectors encoding BMP-2 or GFP and assessed for early and late stages of osteogenic differentiation. Results Immortalization of calvarial cells did not alter cell morphology as demonstrated by phase contrast microscopy. Mesenchymal progenitor cell markers CD166, CD73, CD44, and CD105 were detected at varying levels in both primary cells and iCALs. Significant elevations in alkaline phosphatase activity, osteocalcin mRNA transcription, and matrix mineralization were detected in BMP-2 treated iCALs compared to GFP treated cells. Gross and histological analyses revealed ectopic bone production from treated cells compared to controls in an in vivo stem cell implantation assay. Conclusion We have established an immortalized osteoprogenitor cell line from juvenile calvarial cells that retain a progenitor cell phenotype and can successfully undergo osteogenic differentiation upon BMP-2 stimulation. These cells provide a valuable platform to investigate the molecular mechanisms underlying intramembranous bone formation and to screen for

  3. Matrix metalloproteinase-14 mediates formation of bile ducts and hepatic maturation of fetal hepatic progenitor cells.

    PubMed

    Otani, Satoshi; Kakinuma, Sei; Kamiya, Akihide; Goto, Fumio; Kaneko, Shun; Miyoshi, Masato; Tsunoda, Tomoyuki; Asano, Yu; Kawai-Kitahata, Fukiko; Nitta, Sayuri; Nakata, Toru; Okamoto, Ryuichi; Itsui, Yasuhiro; Nakagawa, Mina; Azuma, Seishin; Asahina, Yasuhiro; Yamaguchi, Tomoyuki; Koshikawa, Naohiko; Seiki, Motoharu; Nakauchi, Hiromitsu; Watanabe, Mamoru

    2016-01-22

    Fetal hepatic stem/progenitor cells, called hepatoblasts, play central roles in liver development; however, the molecular mechanisms regulating the phenotype of these cells have not been completely elucidated. Matrix metalloproteinase (MMP)-14 is a type I transmembrane proteinase regulating pericellular proteolysis of the extracellular matrix and is essential for the activation of several MMPs and cytokines. However, the physiological functions of MMP-14 in liver development are unknown. Here we describe a functional role for MMP-14 in hepatic and biliary differentiation of mouse hepatoblasts. MMP-14 was upregulated in cells around the portal vein in perinatal stage liver. Formation of bile duct-like structures in MMP-14-deficient livers was significantly delayed compared with wild-type livers in vivo. In vitro biliary differentiation assays showed that formation of cholangiocytic cysts derived from MMP-14-deficient hepatoblasts was completely impaired, and that overexpression of MMP-14 in hepatoblasts promoted the formation of bile duct-like cysts. In contrast, the expression of molecules associated with metabolic functions in hepatocytes, including hepatic nuclear factor 4α and tryptophan 2,3-dioxygenase, were significantly increased in MMP-14-deficient livers. Expression of the epidermal growth factor receptor and phosphorylation of mitogen-activated protein kinases were significantly upregulated in MMP-14-deficient livers. We demonstrate that MMP-14-mediated signaling in fetal hepatic progenitor cells promotes biliary luminal formation around the portal vein and negatively controls the maturation of hepatocytes. PMID:26724533

  4. Secondary Sphere Formation Enhances the Functionality of Cardiac Progenitor Cells

    PubMed Central

    Cho, Hyun-Jai; Lee, Ho-Jae; Youn, Seock-Won; Koh, Seok-Jin; Won, Joo-Yun; Chung, Yeon-Ju; Cho, Hyun-Ju; Yoon, Chang-Hwan; Lee, Sae-Won; Lee, Eun Ju; Kwon, Yoo-Wook; Lee, Hae-Young; Lee, Sang Hun; Ho, Won-Kyung; Park, Young-Bae; Kim, Hyo-Soo

    2012-01-01

    Loss of cardiomyocytes impairs cardiac function after myocardial infarction (MI). Recent studies suggest that cardiac stem/progenitor cells could repair the damaged heart. However, cardiac progenitor cells are difficult to maintain in terms of purity and multipotency when propagated in two-dimensional culture systems. Here, we investigated a new strategy that enhances potency and enriches progenitor cells. We applied the repeated sphere formation strategy (cardiac explant → primary cardiosphere (CS) formation → sphere-derived cells (SDCs) in adherent culture condition → secondary CS formation by three-dimensional culture). Cells in secondary CS showed higher differentiation potentials than SDCs. When transplanted into the infarcted myocardium, secondary CSs engrafted robustly, improved left ventricular (LV) dysfunction, and reduced infarct sizes more than SDCs did. In addition to the cardiovascular differentiation of transplanted secondary CSs, robust vascular endothelial growth factor (VEGF) synthesis and secretion enhanced neovascularization in the infarcted myocardium. Microarray pathway analysis and blocking experiments using E-selectin knock-out hearts, specific chemicals, and small interfering RNAs (siRNAs) for each pathway revealed that E-selectin was indispensable to sphere initiation and ERK/Sp1/VEGF autoparacrine loop was responsible for sphere maturation. These results provide a simple strategy for enhancing cellular potency for cardiac repair. Furthermore, this strategy may be implemented to other types of stem/progenitor cell-based therapy. PMID:22713697

  5. Mesenchymal cells. Defining a mesenchymal progenitor niche at single-cell resolution.

    PubMed

    Kumar, Maya E; Bogard, Patrick E; Espinoza, F Hernán; Menke, Douglas B; Kingsley, David M; Krasnow, Mark A

    2014-11-14

    Most vertebrate organs are composed of epithelium surrounded by support and stromal tissues formed from mesenchyme cells, which are not generally thought to form organized progenitor pools. Here, we use clonal cell labeling with multicolor reporters to characterize individual mesenchymal progenitors in the developing mouse lung. We observe a diversity of mesenchymal progenitor populations with different locations, movements, and lineage boundaries. Airway smooth muscle (ASM) progenitors map exclusively to mesenchyme ahead of budding airways. Progenitors recruited from these tip pools differentiate into ASM around airway stalks; flanking stalk mesenchyme can be induced to form an ASM niche by a lateral bud or by an airway tip plus focal Wnt signal. Thus, mesenchymal progenitors can be organized into localized and carefully controlled domains that rival epithelial progenitor niches in regulatory sophistication. PMID:25395543

  6. Growth of melanocytes in human epidermal cell cultures

    SciTech Connect

    Staiano-Coico, L.; Hefton, J.M.; Amadeo, C.; Pagan-Charry, I.; Madden, M.R.; Cardon-Cardo, C. )

    1990-08-01

    Epidermal cell cultures were grown in keratinocyte-conditioned medium for use as burn wound grafts; the melanocyte composition of the grafts was studied under a variety of conditions. Melanocytes were identified by immunohistochemistry based on a monoclonal antibody (MEL-5) that has previously been shown to react specifically with melanocytes. During the first 7 days of growth in primary culture, the total number of melanocytes in the epidermal cultures decreased to 10% of the number present in normal skin. Beginning on day 2 of culture, bipolar melanocytes were present at a mean cell density of 116 +/- 2/mm2; the keratinocyte to melanocyte ratio was preserved during further primary culture and through three subpassages. Moreover, exposure of cultures to mild UVB irradiation stimulated the melanocytes to proliferate, suggesting that the melanocytes growing in culture maintained their responsiveness to external stimuli. When the sheets of cultured cells were enzymatically detached from the plastic culture flasks before grafting, melanocytes remained in the basal layer of cells as part of the graft applied to the patient.

  7. Clonal analysis of human dendritic cell progenitor using a stromal cell culture

    PubMed Central

    Lee, Jaeyop; Breton, Gaëlle; Aljoufi, Arafat; Zhou, Yu Jerry; Puhr, Sarah; Nussenzweig, Michel C.; Liu, Kang

    2015-01-01

    Different dendritic cell (DC) subsets co-exist in humans and coordinate the immune response. Having a short life, DCs must be constantly replenished from their progenitors in the bone marrow through hematopoiesis. Identification of a DC-restricted progenitor in mouse has improved our understanding of how DC lineage diverges from myeloid and lymphoid lineages. However, identification of the DC-restricted progenitor in humans has not been possible because a system that simultaneously nurtures differentiation of human DCs, myeloid and lymphoid cells, is lacking. Here we report a cytokine and stromal cell culture that allows evaluation of CD34+ progenitor potential to all three DC subsets as well as other myeloid and lymphoid cells, at a single cell level. Using this system, we show that human granulocyte–macrophage progenitors are heterogeneous and contain restricted progenitors to DCs. PMID:26056939

  8. LPS induces pulp progenitor cell recruitment via complement activation.

    PubMed

    Chmilewsky, F; Jeanneau, C; Laurent, P; About, I

    2015-01-01

    Complement system, a major component of the natural immunity, has been recently identified as an important mediator of the dentin-pulp regeneration process through STRO-1 pulp cell recruitment by the C5a active fragment. Moreover, it has been shown recently that under stimulation with lipoteichoic acid, a complex component of the Gram-positive bacteria cell wall, human pulp fibroblasts are able to synthesize all proteins required for complement activation. However, Gram-negative bacteria, which are also involved in tooth decay, are known as powerful activators of complement system and inflammation. Here, we investigated the role of Gram-negative bacteria-induced complement activation on the pulp progenitor cell recruitment using lipopolysaccharide (LPS), a major component of all Gram-negative bacteria. Our results show that incubating pulp fibroblasts with LPS induced membrane attack complex formation and C5a release in serum-free fibroblast cultures. The produced C5a binds to the pulp progenitor cells' membrane and induces their migration toward the LPS stimulation chamber, as revealed by the dynamic transwell migration assays. The inhibition of this migration by the C5aR-specific antagonist W54011 indicates that the pulp progenitor migration is mediated by the interaction between C5a and C5aR. Our findings demonstrate, for the first time, a direct interaction between the recruitment of progenitor pulp cells and the activation of complement system generated by pulp fibroblast stimulation with LPS. PMID:25359783

  9. Epidermal cell growth-dependent arylhydrocarbon-hydroxylase (AHH) activity in vitro.

    PubMed

    Thiele, B; Merk, H F; Bonnekoh, B; Mahrle, G; Steigleder, G K

    1987-01-01

    Cytochrome P-450-dependent arylhydrocarbon-hydroxylase (AHH) activity and inducibility by benzanthracene (BA) was measured in cultured guinea pig and human epidermal cells. Basal AHH-activity (AHHb) in guinea pig epidermal cells was much higher than in human epidermal cells. AHHb in guinea pig epidermal cells was directly related to the labeling index and decreased to the original level between the 5th and 7th day of cell culturing. On the other hand, the induction-ratio of AHH reached its maximum level when the number of cells began to rise (proliferation phase) and remained high at day 7 of the cell culture. These results suggest a cell growth dependent activity and inducibility of carcinogen-metabolizing enzymes, such as AHH, in isolated epidermal cells. PMID:3435181

  10. A Progenitor Cell Expressing Transcription Factor RORγt Generates All Human Innate Lymphoid Cell Subsets.

    PubMed

    Scoville, Steven D; Mundy-Bosse, Bethany L; Zhang, Michael H; Chen, Li; Zhang, Xiaoli; Keller, Karen A; Hughes, Tiffany; Chen, Luxi; Cheng, Stephanie; Bergin, Stephen M; Mao, Hsiaoyin C; McClory, Susan; Yu, Jianhua; Carson, William E; Caligiuri, Michael A; Freud, Aharon G

    2016-05-17

    The current model of murine innate lymphoid cell (ILC) development holds that mouse ILCs are derived downstream of the common lymphoid progenitor through lineage-restricted progenitors. However, corresponding lineage-restricted progenitors in humans have yet to be discovered. Here we identified a progenitor population in human secondary lymphoid tissues (SLTs) that expressed the transcription factor RORγt and was unique in its ability to generate all known ILC subsets, including natural killer (NK) cells, but not other leukocyte populations. In contrast to murine fate-mapping data, which indicate that only ILC3s express Rorγt, these human progenitor cells as well as human peripheral blood NK cells and all mature ILC populations expressed RORγt. Thus, all human ILCs can be generated through an RORγt(+) developmental pathway from a common progenitor in SLTs. These findings help establish the developmental signals and pathways involved in human ILC development. PMID:27178467

  11. Hematopoietic stem/progenitor cell commitment to the megakaryocyte lineage.

    PubMed

    Woolthuis, Carolien M; Park, Christopher Y

    2016-03-10

    The classical model of hematopoiesis has long held that hematopoietic stem cells (HSCs) sit at the apex of a developmental hierarchy in which HSCs undergo long-term self-renewal while giving rise to cells of all the blood lineages. In this model, self-renewing HSCs progressively lose the capacity for self-renewal as they transit into short-term self-renewing and multipotent progenitor states, with the first major lineage commitment occurring in multipotent progenitors, thus giving rise to progenitors that initiate the myeloid and lymphoid branches of hematopoiesis. Subsequently, within the myeloid lineage, bipotent megakaryocyte-erythrocyte and granulocyte-macrophage progenitors give rise to unipotent progenitors that ultimately give rise to all mature progeny. However, over the past several years, this developmental scheme has been challenged, with the origin of megakaryocyte precursors being one of the most debated subjects. Recent studies have suggested that megakaryocytes can be generated from multiple pathways and that some differentiation pathways do not require transit through a requisite multipotent or bipotent megakaryocyte-erythrocyte progenitor stage. Indeed, some investigators have argued that HSCs contain a subset of cells with biased megakaryocyte potential, with megakaryocytes directly arising from HSCs under steady-state and stress conditions. In this review, we discuss the evidence supporting these nonclassical megakaryocytic differentiation pathways and consider their relative strengths and weaknesses as well as the technical limitations and potential pitfalls in interpreting these studies. Ultimately, such pitfalls will need to be overcome to provide a comprehensive and definitive understanding of megakaryopoiesis. PMID:26787736

  12. Endothelial cells are progenitors of cardiac pericytes and vascular smooth muscle cells

    PubMed Central

    Chen, Qi; Zhang, Hui; Liu, Yang; Adams, Susanne; Eilken, Hanna; Stehling, Martin; Corada, Monica; Dejana, Elisabetta; Zhou, Bin; Adams, Ralf H.

    2016-01-01

    Mural cells of the vessel wall, namely pericytes and vascular smooth muscle cells, are essential for vascular integrity. The developmental sources of these cells and molecular mechanisms controlling their progenitors in the heart are only partially understood. Here we show that endocardial endothelial cells are progenitors of pericytes and vascular smooth muscle cells in the murine embryonic heart. Endocardial cells undergo endothelial–mesenchymal transition and convert into primitive mesenchymal progenitors expressing the platelet-derived growth factor receptors, PDGFRα and PDGFRβ. These progenitors migrate into the myocardium, differentiate and assemble the wall of coronary vessels, which requires canonical Wnt signalling involving Frizzled4, β-catenin and endothelial cell-derived Wnt ligands. Our findings identify a novel and unexpected population of progenitors for coronary mural cells with potential relevance for heart function and disease conditions. PMID:27516371

  13. Endothelial cells are progenitors of cardiac pericytes and vascular smooth muscle cells.

    PubMed

    Chen, Qi; Zhang, Hui; Liu, Yang; Adams, Susanne; Eilken, Hanna; Stehling, Martin; Corada, Monica; Dejana, Elisabetta; Zhou, Bin; Adams, Ralf H

    2016-01-01

    Mural cells of the vessel wall, namely pericytes and vascular smooth muscle cells, are essential for vascular integrity. The developmental sources of these cells and molecular mechanisms controlling their progenitors in the heart are only partially understood. Here we show that endocardial endothelial cells are progenitors of pericytes and vascular smooth muscle cells in the murine embryonic heart. Endocardial cells undergo endothelial-mesenchymal transition and convert into primitive mesenchymal progenitors expressing the platelet-derived growth factor receptors, PDGFRα and PDGFRβ. These progenitors migrate into the myocardium, differentiate and assemble the wall of coronary vessels, which requires canonical Wnt signalling involving Frizzled4, β-catenin and endothelial cell-derived Wnt ligands. Our findings identify a novel and unexpected population of progenitors for coronary mural cells with potential relevance for heart function and disease conditions. PMID:27516371

  14. Sox2 in the differentiation of cochlear progenitor cells

    PubMed Central

    Kempfle, Judith S.; Turban, Jack L.; Edge, Albert S. B.

    2016-01-01

    HMG domain transcription factor, Sox2, is a critical gene for the development of cochlear hair cells, the receptor cells for hearing, but this has been ascribed to expansion of the progenitors that become hair cells. Here, we show that Sox2 activated Atoh1, a transcription factor important for hair cell differentiation, through an interaction with the 3′ enhancer of Atoh1. Binding to consensus sequences in the Atoh1 enhancer was dependent on the level of Sox2, and the extent of enhancer binding correlated to the extent of activation. Atoh1 activation by Sox2 was required for embryonic hair cell development: deletion of Sox2 in an inducible mutant, even after progenitor cells were fully established, halted development of hair cells, and silencing also inhibited postnatal differentiation of hair cells induced by inhibition of γ-secretase. Sox2 is thus required in the cochlea to both expand the progenitor cells and initiate their differentiation to hair cells. PMID:26988140

  15. Sox2 in the differentiation of cochlear progenitor cells.

    PubMed

    Kempfle, Judith S; Turban, Jack L; Edge, Albert S B

    2016-01-01

    HMG domain transcription factor, Sox2, is a critical gene for the development of cochlear hair cells, the receptor cells for hearing, but this has been ascribed to expansion of the progenitors that become hair cells. Here, we show that Sox2 activated Atoh1, a transcription factor important for hair cell differentiation, through an interaction with the 3' enhancer of Atoh1. Binding to consensus sequences in the Atoh1 enhancer was dependent on the level of Sox2, and the extent of enhancer binding correlated to the extent of activation. Atoh1 activation by Sox2 was required for embryonic hair cell development: deletion of Sox2 in an inducible mutant, even after progenitor cells were fully established, halted development of hair cells, and silencing also inhibited postnatal differentiation of hair cells induced by inhibition of γ-secretase. Sox2 is thus required in the cochlea to both expand the progenitor cells and initiate their differentiation to hair cells. PMID:26988140

  16. In vitro transformation of Syrian hamster epidermal cells by N-methyl-N'-nitro-N-nitrosoguanidine

    SciTech Connect

    Sun, N.C.; Sun, C.R.Y.; Chao, L.; Fung, W.P.; Tennant, R.W.; Hsie, A.W.

    1981-05-01

    The selection of Syrian hamster epidermal cells which do not terminally differentiate has provided a quantitative focus assay for in vitro chemical transformation. One-day-old Syrian hamster epidermal cells plated at 5 x 10/sup 6//100-mm dish were treated for 5 hr with various concentrations of N-methyl-N-nitro-N'-nitrosoguanidine. After 4 weeks, the normal epidermal cells began to terminally differentiate to keratinized squamous cells and died, but transformed epidermal colonies grew to higher cell densities and appeared as darker areas against a lightly stained normal cell background. Transformed epidermal foci were isolated and subcultured for at least 15 passages, whereas normal epidermal cells could not be subcultured under the same conditions. The transformed cells assumed the typical cobblestone-like morphology of epithelial cells, retained desmosomes and tonofilaments, and were able to use citrulline in place of arginine. Argininosuccinate synthetase (EC 6.3.4.5) activity was significantly higher in the epidermal cells than in fibroblasts. The injection of 5 x 10/sup 6/ cells of two transformed epidermal cell lines into athymic nude mice resulted in the formation of tumors which were identified as keratinizing squamous carcinomas.

  17. Centroacinar Cells Are Progenitors That Contribute to Endocrine Pancreas Regeneration.

    PubMed

    Delaspre, Fabien; Beer, Rebecca L; Rovira, Meritxell; Huang, Wei; Wang, Guangliang; Gee, Stephen; Vitery, Maria del Carmen; Wheelan, Sarah J; Parsons, Michael J

    2015-10-01

    Diabetes is associated with a paucity of insulin-producing β-cells. With the goal of finding therapeutic routes to treat diabetes, we aim to find molecular and cellular mechanisms involved in β-cell neogenesis and regeneration. To facilitate discovery of such mechanisms, we use a vertebrate organism where pancreatic cells readily regenerate. The larval zebrafish pancreas contains Notch-responsive progenitors that during development give rise to adult ductal, endocrine, and centroacinar cells (CACs). Adult CACs are also Notch responsive and are morphologically similar to their larval predecessors. To test our hypothesis that adult CACs are also progenitors, we took two complementary approaches: 1) We established the transcriptome for adult CACs. Using gene ontology, transgenic lines, and in situ hybridization, we found that the CAC transcriptome is enriched for progenitor markers. 2) Using lineage tracing, we demonstrated that CACs do form new endocrine cells after β-cell ablation or partial pancreatectomy. We concluded that CACs and their larval predecessors are the same cell type and represent an opportune model to study both β-cell neogenesis and β-cell regeneration. Furthermore, we show that in cftr loss-of-function mutants, there is a deficiency of larval CACs, providing a possible explanation for pancreatic complications associated with cystic fibrosis. PMID:26153247

  18. Human neural progenitor cells in central nervous system lesions.

    PubMed

    Åkesson, Elisabet; Sundström, Erik

    2016-02-01

    Various immature cells can be isolated from human embryonic and fetal central nervous system (CNS) residual tissue and potentially be used in cell therapy for a number of neurological diseases and CNS insults. Transplantation of neural stem and progenitor cells is essential for replacing lost cells, particularly in the CNS with very limited endogenous regenerative capacity. However, while dopamine released from transplanted cells can substitute the lost dopamine neurons in the experimental models of Parkinson's disease, stem and progenitor cells primarily have a neuroprotective effect, probably through the release of trophic factors. Understanding the therapeutic effects of transplanted cells is crucial to determine the design of clinical trials. During the last few years, a number of clinical trials for CNS diseases and insults such as amyotrophic lateral sclerosis (ALS), stroke, and spinal cord trauma using neural progenitor cells have been initiated. Data from these early studies will provide vital information on the safety of transplanting these cells, which still is a major concern. That the beneficial results observed in experimental models also can be repeated in the clinical setting is highly hoped for. PMID:26803559

  19. Programmed Cell Death Progresses Differentially in Epidermal and Mesophyll Cells of Lily Petals.

    PubMed

    Mochizuki-Kawai, Hiroko; Niki, Tomoko; Shibuya, Kenichi; Ichimura, Kazuo

    2015-01-01

    In the petals of some species of flowers, programmed cell death (PCD) begins earlier in mesophyll cells than in epidermal cells. However, PCD progression in each cell type has not been characterized in detail. We separately constructed a time course of biochemical signs and expression patterns of PCD-associated genes in epidermal and mesophyll cells in Lilium cv. Yelloween petals. Before visible signs of senescence could be observed, we found signs of PCD, including DNA degradation and decreased protein content in mesophyll cells only. In these cells, the total proteinase activity increased on the day after anthesis. Within 3 days after anthesis, the protein content decreased by 61.8%, and 22.8% of mesophyll cells was lost. A second peak of proteinase activity was observed on day 6, and the number of mesophyll cells decreased again from days 4 to 7. These biochemical and morphological results suggest that PCD progressed in steps during flower life in the mesophyll cells. PCD began in epidermal cells on day 5, in temporal synchrony with the time course of visible senescence. In the mesophyll cells, the KDEL-tailed cysteine proteinase (LoCYP) and S1/P1 nuclease (LoNUC) genes were upregulated before petal wilting, earlier than in epidermal cells. In contrast, relative to that in the mesophyll cells, the expression of the SAG12 cysteine proteinase homolog (LoSAG12) drastically increased in epidermal cells in the final stage of senescence. These results suggest that multiple PCD-associated genes differentially contribute to the time lag of PCD progression between epidermal and mesophyll cells of lily petals. PMID:26605547

  20. Programmed Cell Death Progresses Differentially in Epidermal and Mesophyll Cells of Lily Petals

    PubMed Central

    Mochizuki-Kawai, Hiroko; Niki, Tomoko; Shibuya, Kenichi; Ichimura, Kazuo

    2015-01-01

    In the petals of some species of flowers, programmed cell death (PCD) begins earlier in mesophyll cells than in epidermal cells. However, PCD progression in each cell type has not been characterized in detail. We separately constructed a time course of biochemical signs and expression patterns of PCD-associated genes in epidermal and mesophyll cells in Lilium cv. Yelloween petals. Before visible signs of senescence could be observed, we found signs of PCD, including DNA degradation and decreased protein content in mesophyll cells only. In these cells, the total proteinase activity increased on the day after anthesis. Within 3 days after anthesis, the protein content decreased by 61.8%, and 22.8% of mesophyll cells was lost. A second peak of proteinase activity was observed on day 6, and the number of mesophyll cells decreased again from days 4 to 7. These biochemical and morphological results suggest that PCD progressed in steps during flower life in the mesophyll cells. PCD began in epidermal cells on day 5, in temporal synchrony with the time course of visible senescence. In the mesophyll cells, the KDEL-tailed cysteine proteinase (LoCYP) and S1/P1 nuclease (LoNUC) genes were upregulated before petal wilting, earlier than in epidermal cells. In contrast, relative to that in the mesophyll cells, the expression of the SAG12 cysteine proteinase homolog (LoSAG12) drastically increased in epidermal cells in the final stage of senescence. These results suggest that multiple PCD-associated genes differentially contribute to the time lag of PCD progression between epidermal and mesophyll cells of lily petals. PMID:26605547

  1. Properties of Adult Lung Stem and Progenitor Cells.

    PubMed

    Bertoncello, Ivan

    2016-12-01

    The last decade has seen significant progress in understanding the organisation of regenerative cells in the adult lung. Cell-lineage tracing and in vitro clonogenic assays have enabled the identification and characterisation of endogenous lung epithelial stem and progenitor cells. Selective lung injury models, and genetically engineered mice have revealed highly conserved gene networks, factors, signalling pathways, and cellular interactions important in maintaining lung homeostasis and regulating lung regeneration and repair following injury. This review describes the current models of lung epithelial stem and progenitor cell organisation in adult mice, and the impediments encountered in translational studies aiming to identify and characterise their human homologs. J. Cell. Physiol. 231: 2582-2589, 2016. © 2016 Wiley Periodicals, Inc. PMID:27062064

  2. Host cell reactivation studies with epidermal cells of mice sensitive and resistant to carcinogenesis

    SciTech Connect

    Strickland, J.E.; Strickland, A.G.

    1984-03-01

    Primary epidermal cells from AKR, BALB/c, CD-1, and SENCAR mice, listed in order of least to most sensitive to epidermal carcinogenesis by initiation and promotion protocols, were found to be equally competent to ''reactivate'' herpes simplex virus type 1 irradiated by germicidal ultraviolet radiation. Nontumorigenic BALB/c epidermal cell lines selected in vitro for resistance to terminal differentiation after in vivo or in vitro treatment with initiating doses of carcinogens showed virus survival curves similar to those of primary cells. Similarly, primary cultures which were allowed to grow to confluency following a single treatment with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (100 ng/ml) retained normal host cell reactivation. Host cell reactivation studies with mouse dermal fibroblasts could not be done because of the failure of the herpes simplex virus to infect these cells and produce plaques. These results demonstrate that survival of ultraviolet light-damaged virus in primary epidermal cells in culture is unrelated to whether the cells are derived from mice sensitive or resistant to epidermal carcinogenesis. Furthermore, virus survival is not changed by tumor promoter treatment or by treatment with initiating doses of carcinogens which results in differentiation-resistant cells.

  3. Vertebrate epidermal cells are broad-specificity phagocytes that clear sensory axon debris.

    PubMed

    Rasmussen, Jeffrey P; Sack, Georgeann S; Martin, Seanna M; Sagasti, Alvaro

    2015-01-14

    Cellular debris created by developmental processes or injury must be cleared by phagocytic cells to maintain and repair tissues. Cutaneous injuries damage not only epidermal cells but also the axonal endings of somatosensory (touch-sensing) neurons, which must be repaired to restore the sensory function of the skin. Phagocytosis of neuronal debris is usually performed by macrophages or other blood-derived professional phagocytes, but we have found that epidermal cells phagocytose somatosensory axon debris in zebrafish. Live imaging revealed that epidermal cells rapidly internalize debris into dynamic phosphatidylinositol 3-monophosphate-positive phagosomes that mature into phagolysosomes using a pathway similar to that of professional phagocytes. Epidermal cells phagocytosed not only somatosensory axon debris but also debris created by injury to other peripheral axons that were mislocalized to the skin, neighboring skin cells, and macrophages. Together, these results identify vertebrate epidermal cells as broad-specificity phagocytes that likely contribute to neural repair and wound healing. PMID:25589751

  4. Regional differences in stem cell/progenitor cell populations from the mouse achilles tendon.

    PubMed

    Mienaltowski, Michael J; Adams, Sheila M; Birk, David E

    2013-01-01

    Specific niches may affect how cells from different regions contribute to tendon biology, particularly in regard to the healing of certain tendinopathies. The objectives of this study are to determine whether distinct subpopulations of stem/progenitor cells are found within the tendon proper and the epi- and paratenon, the peritenon, as well as to characterize these stem/progenitor cell populations. In this study, we hypothesized that tendon stem/progenitor cells exist in each region, that these populations possess distinct features, and that these populations while multipotent could have differing potentials. To test this hypothesis, stem/progenitor cells were isolated and characterized from the peritenon and tendon proper of mouse Achilles tendons. Colony-forming unit and multipotency assays, as well as flow cytometry, and real-time quantitative polymerase chain reaction analyses of stem cell markers were performed. Significantly, more stem/progenitor cell colonies were observed from cells derived from the tendon proper relative to the peritenon. Analysis of surface markers for stem/progenitor cells from both regions indicated that they were Sca1(+) (stem cell marker), Cd90(+) and Cd44(+) (fibroblast markers), Cd18(-) (leukocyte marker), Cd34(-) (hematopoietic and vascular marker), and Cd133(-) (perivascular marker). Tendon proper stem/progenitor cells had increased expression levels for tenomodulin (Tnmd) and scleraxis (Scx), indicative of enrichment of stem/progenitor cells of a tendon origin. In contrast, cells of the peritenon demonstrated relative increases in the vascular (endomucin) and pericyte (Cd133) markers relative to cells from the tendon proper. Stem/progenitor cells from both regions were multipotent (adipogenic, chondrogenic, osteogenic, and tenogenic). These findings demonstrated that different progenitor populations exist within discrete niches of the Achilles tendon-tendon proper versus peritenon. Overall, these data support the hypothesis that

  5. Pericardial patch venoplasty heals via attraction of venous progenitor cells.

    PubMed

    Bai, Hualong; Wang, Mo; Foster, Trenton R; Hu, Haidi; He, Hao; Hashimoto, Takuya; Hanisch, Jesse J; Santana, Jeans M; Xing, Ying; Dardik, Alan

    2016-06-01

    Pericardial patches are commonly used during cardiovascular surgery to close blood vessels. In arteries, patches accumulate arterial progenitor cells; we hypothesized that venous patches would accumulate venous progenitor cells, in the absence of arterial pressure. We developed a novel rat inferior vena cava (IVC) venotomy model and repaired it with a pericardial patch. Cells infiltrated the patch to form a thick neointima by day 7; some cells were CD34(+)/VEGFR2(+) and CD31(+)/Eph-B4(+) consistent with development of venous identity in the healing patch. Compared to arterial patches, the venous patches had increased neointimal thickness at day 7 without any pseudoaneurysms. Addition of an arteriovenous fistula (AVF) to increase blood flow on the patch resulted in reduced patch neointimal thickness and proliferation, but neointimal thickness was not reversible with AVF ligation. These results show that rat patch venoplasty is a novel model of aggressive venous neointimal hyperplasia. PMID:27354544

  6. Transplantation of Adrenal Cortical Progenitor Cells Enriched by Nile Red

    PubMed Central

    Dunn, James C.Y.; Chu, Yinting; Qin, Harry H.; Zupekan, Tatiana

    2009-01-01

    Background The adrenal cortex may contain progenitor cells useful for tissue regeneration. Currently there are no established methods to isolate these cells. Material and Methods Murine adrenal cells were sorted into a Nile-Red-bright (NRbright) and a Nile-Red-dim (NRdim) population of cells according to their degree of cholesterol content revealed by Nile Red fluorescence. The cells were transplanted under the renal capsule to determine their ability for regeneration. Results The NRbright cells contained an abundance of lipid droplets, whereas the NRdim cells contained little. The NRbright cells expressed Sf1 and the more differentiated adrenal cortical genes including Cyp11a1, Cyp11b1, and Cyp11b2, whereas the NRdim cells expressed Sf1 but not the more differentiated adrenal cortical genes. After 56 days of implantation in unilateral adrenalectomized mice, the NRdim cells expressed Sf1 and the more differentiated adrenal cortical genes, whereas the NRbright cells ceased to express Sf1 as well as the more differentiated adrenal cortical genes. NRdim cells also proliferated in the presence of basic fibroblast growth factor. Conclusions The population of NRdim cells contained adrenal cortical progenitor cells that can proliferate and give rise to differentiated daughter cells. These cells may be useful for adrenal cortical regeneration. PMID:19592014

  7. Isolating Mesangiogenic Progenitor Cells (MPCs) from Human Bone Marrow.

    PubMed

    Montali, Marina; Barachini, Serena; Pacini, Simone; Panvini, Francesca M; Petrini, Mario

    2016-01-01

    In a research study aimed to isolate human bone marrow (hBM)-derived Mesenchymal Stromal Cells (MSCs) for clinical applications, we identified a novel cell population specifically selected for growth in human serum supplemented medium. These cells are characterized by morphological, phenotypic, and molecular features distinct from MSCs and we named them Mesodermal Progenitor Cells (MPCs). MPCs are round, with a thick highly refringent core region; they show strong, trypsin resistant adherence to plastic. Failure to expand MPCs directly revealed that they are slow in cycling. This is as also suggested by Ki-67 negativity. On the other hand, culturing MPCs in standard medium designed for MSC expansion, gave rise to a population of exponentially growing MSC-like cells. Besides showing mesenchymal differentiation capacity MPCs retained angiogenic potential, confirming their multiple lineage progenitor nature. Here we describe an optimized highly reproducible protocol to isolate and characterize hBM-MPCs by flow cytometry (CD73, CD90, CD31, and CD45), nestin expression, and F-actin organization. Protocols for mesengenic and angiogenic differentiation of MPCs are also provided. Here we also suggest a more appropriate nomenclature for these cells, which has been re-named as "Mesangiogenic Progenitor Cells". PMID:27500428

  8. Water Relations of Leaf Epidermal Cells of Tradescantia virginiana12

    PubMed Central

    Tomos, Alun Deri; Steudle, Ernst; Zimmermann, Ulrich; Schulze, Ernst-Detlev

    1981-01-01

    Water-relation parameters (cell turgor pressure [P], volumetric elastic modulus [ε] and hydraulic conductivity [Lp]) of individual leaf epidermal cells of Tradescantia virginiana have been determined with the pressure-probe technique. Turgor was 4.5 ± 2.1 [41] bar (mean ± sd; in brackets the number of cells) and ranged from 0.9 to 9.6 bar. By vacuum infiltration with nutrient solution, it was raised to 7.5 ± 1.5 [5] bar (range: 5.3-8.8 bar). There was a large variability in the absolute value of ε of individual cells. ε ranged from 40 to 360 bar; mean ± sd: 135 ± 83 bar; n = 50 cells. ε values of individual cells seemed to be rather independent of changes in cell turgor. A critical assessment of the errors incurred in determining ε by the technique is included. The half-times of water exchange of individual cells ranged from 1 to 35 seconds, which gave values of 0.2 to 11 × 10−6 centimeters per second per bar for Lp (mean ± sd: 3.1 ± 2.3 × 10−6 centimeters per second per bar; n = 39 cells). The large range in Lp and ε is believed to be due to the difficulties in determining the effective surface area of water exchange of the cells. Lp is not influenced by active salt pumping driven by respiration energy inasmuch as it was not altered by 0.1 millimolar KCN. The temperature dependence of Lp (T½) was measured for the first time in individual higher-plant cells. Lp increased by a factor of 2 to 4, when the temperature was increased by 10 C. The activation energy of water exchange was found to be between 50 and 186 kilojoules per mole. Within the large range of variation it was found that T½, Lp, and ε did not change under various experimental conditions (intact and excised tissue, water content and turgidity, age, etc.). Similar results were obtained for the epidermal cells of Tradescantia andersoniana. The measurements suggest that the entire epidermis would respond very rapidly (i.e. with a half-time of 1 to 30 s) to a demand for water from the

  9. Selection of Phage Display Peptides Targeting Human Pluripotent Stem Cell-Derived Progenitor Cell Lines.

    PubMed

    Bignone, Paola A; Krupa, Rachel A; West, Michael D; Larocca, David

    2016-01-01

    The ability of human pluripotent stem cells (hPS) to both self-renew and differentiate into virtually any cell type makes them a promising source of cells for cell-based regenerative therapies. However, stem cell identity, purity, and scalability remain formidable challenges that need to be overcome for translation of pluripotent stem cell research into clinical applications. Directed differentiation from hPS cells is inefficient and residual contamination with pluripotent cells that have the potential to form tumors remains problematic. The derivation of scalable (self-renewing) embryonic progenitor stem cell lines offers a solution because they are well defined and clonally pure. Clonally pure progenitor stem cell lines also provide a means for identifying cell surface targeting reagents that are useful for identification, tracking, and repeated derivation of the corresponding progenitor stem cell types from additional hPS cell sources. Such stem cell targeting reagents can then be applied to the manufacture of genetically diverse banks of human embryonic progenitor cell lines for drug screening, disease modeling, and cell therapy. Here we present methods to identify human embryonic progenitor stem cell targeting peptides by selection of phage display libraries on clonal embryonic progenitor cell lines and demonstrate their use for targeting quantum dots (Qdots) for stem cell labeling. PMID:25410289

  10. Alteration of cardiac progenitor cell potency in GRMD dogs.

    PubMed

    Cassano, M; Berardi, E; Crippa, S; Toelen, J; Barthelemy, I; Micheletti, R; Chuah, M; Vandendriessche, T; Debyser, Z; Blot, S; Sampaolesi, M

    2012-01-01

    Among the animal models of Duchenne muscular dystrophy (DMD), the Golden Retriever muscular dystrophy (GRMD) dog is considered the best model in terms of size and pathological onset of the disease. As in human patients presenting with DMD or Becker muscular dystrophies (BMD), the GRMD is related to a spontaneous X-linked mutation of dystrophin and is characterized by myocardial lesions. In this respect, GRMD is a useful model to explore cardiac pathogenesis and for the development of therapeutic protocols. To investigate whether cardiac progenitor cells (CPCs) isolated from healthy and GRMD dogs may differentiate into myocardial cell types and to test the feasibility of cell therapy for cardiomyopathies in a preclinical model of DMD, CPCs were isolated from cardiac biopsies of healthy and GRMD dogs. Gene profile analysis revealed an active cardiac transcription network in both healthy and GRMD CPCs. However, GRMD CPCs showed impaired self-renewal and cardiac differentiation. Population doubling and telomerase analyses highlighted earlier senescence and proliferation impairment in progenitors isolated from GRMD cardiac biopsies. Immunofluorescence analysis revealed that only wt CPCs showed efficient although not terminal cardiac differentiation, consistent with the upregulation of cardiac-specific proteins and microRNAs. Thus, the pathological condition adversely influences the cardiomyogenic differentiation potential of cardiac progenitors. Using PiggyBac transposon technology we marked CPCs for nuclear dsRed expression, providing a stable nonviral gene marking method for in vivo tracing of CPCs. Xenotransplantation experiments in neonatal immunodeficient mice revealed a valuable contribution of CPCs to cardiomyogenesis with homing differences between wt and dystrophic progenitors. These results suggest that cardiac degeneration in dystrophinopathies may account for the progressive exhaustion of local cardiac progenitors and shed light on cardiac stemness in

  11. Minor histocompatibility antigens on canine hemopoietic progenitor cells.

    PubMed

    Weber, Martin; Lange, Claudia; Günther, Wolfgang; Franz, Monika; Kremmer, Elisabeth; Kolb, Hans-Jochem

    2003-06-15

    Adoptive immunotherapy with CTL against minor histocompatibility Ags (mHA) provides a promising way to treat leukemia relapse in allogeneic chimeras. Here we describe the in vitro generation of CTL against mHA in the dog. We tested their inhibitory effect on the growth of hemopoietic progenitor cells stimulated by hemopoietic growth factors in a 4-day suspension culture. CTL were produced by coculture of donor PBMC with bone marrow-derived dendritic cells (DCs). These DCs were characterized by morphology, high expression of MHC class II and CD1a, and the absence of the monocyte-specific marker CD14. Characteristically these cells stimulated allogeneic lymphocytes (MLR) and, after pulsing with a foreign Ag (keyhole limpet hemocyanin), autologous T cells. CTL were generated either ex vivo by coculture with DCs of DLA-identical littermates or in vivo by immunization of the responder with DCs obtained from a DLA-identical littermate. In suspension culture assays the growth of hemopoietic progenitor cells was inhibited in 53% of DLA-identical littermate combinations. In canine families mHA segregated with DLA as restriction elements. One-way reactivity against mHA was found in five littermate combinations. In two cases mHA might be Y chromosome associated, in three cases autosomally inherited alleles were detected. We conclude that CTL can be produced in vitro and in vivo against mHA on canine hemopoietic progenitor cells using bone marrow-derived DCs. PMID:12794111

  12. Effects of Wnt3a on proliferation and differentiation of human epidermal stem cells

    SciTech Connect

    Jia Liwei; Zhou Jiaxi; Peng Sha; Li Juxue; Cao Yujing; Duan Enkui

    2008-04-11

    Epidermal stem cells maintain development and homeostasis of mammalian epidermis throughout life. However, the molecular mechanisms involved in the proliferation and differentiation of epidermal stem cells are far from clear. In this study, we investigated the effects of Wnt3a and Wnt/{beta}-catenin signaling on proliferation and differentiation of human fetal epidermal stem cells. We found both Wnt3a and active {beta}-catenin, two key members of the Wnt/{beta}-catenin signaling, were expressed in human fetal epidermis and epidermal stem cells. In addition, Wnt3a protein can promote proliferation and inhibit differentiation of epidermal stem cells in vitro culture. Our results suggest that Wnt/{beta}-catenin signaling plays important roles in human fetal skin development and homeostasis, which also provide new insights on the molecular mechanisms of oncogenesis in human epidermis.

  13. Dentin regeneration using deciduous pulp stem/progenitor cells.

    PubMed

    Zheng, Y; Wang, X Y; Wang, Y M; Liu, X Y; Zhang, C M; Hou, B X; Wang, S L

    2012-07-01

    Reparative dentin formation is essential for maintaining the integrity of dentin structure during disease or trauma. In this study, we investigated stem/progenitor cell-based tissue engineering for dentin regeneration in a large animal model. Porcine deciduous pulp stem/progenitor cells (PDPSCs) were mixed with a beta-tricalcium phosphate (β-TCP) scaffold for dentin regeneration. Different concentrations of PDPSCs were tested to determine the optimal density for dentin regeneration. Aliquots of 5×10(5) PDPSCs in 1 mL resulted in the highest number of cells attached to the scaffold and the greatest alkaline phosphatase activity. We labeled PDPSCs with green fluorescent protein (GFP) and used the optimal cell numbers mixed with β-TCP to repair pulp chamber roof defects in the premolars of swine. Four weeks after transplantation, GFP-positive PDPSCs were observed in PDPSC-embedded scaffold constructs. At 16 weeks after transplantation, the PDPSCs mixed with β-TCP significantly regenerated the dentin-like structures and nearly completely restored the pulp chamber roof defects. This study demonstrated that the PDPSC/scaffold construct was useful in direct pulp-capping and provides pre-clinical evidence for stem/progenitor cell-based dentin regeneration. PMID:22660968

  14. Efficacy and Safety of Human Retinal Progenitor Cells

    PubMed Central

    Semo, Ma'ayan; Haamedi, Nasrin; Stevanato, Lara; Carter, David; Brooke, Gary; Young, Michael; Coffey, Peter; Sinden, John; Patel, Sara; Vugler, Anthony

    2016-01-01

    Purpose We assessed the long-term efficacy and safety of human retinal progenitor cells (hRPC) using established rodent models. Methods Efficacy of hRPC was tested initially in Royal College of Surgeons (RCS) dystrophic rats immunosuppressed with cyclosporine/dexamethasone. Due to adverse effects of dexamethasone, this drug was omitted from a subsequent dose-ranging study, where different hRPC doses were tested for their ability to preserve visual function (measured by optokinetic head tracking) and retinal structure in RCS rats at 3 to 6 months after grafting. Safety of hRPC was assessed by subretinal transplantation into wild type (WT) rats and NIH-III nude mice, with analysis at 3 to 6 and 9 months after grafting, respectively. Results The optimal dose of hRPC for preserving visual function/retinal structure in dystrophic rats was 50,000 to 100,000 cells. Human retinal progenitor cells integrated/survived in dystrophic and WT rat retina up to 6 months after grafting and expressed nestin, vimentin, GFAP, and βIII tubulin. Vision and retinal structure remained normal in WT rats injected with hRPC and there was no evidence of tumors. A comparison between dexamethasone-treated and untreated dystrophic rats at 3 months after grafting revealed an unexpected reduction in the baseline visual acuity of dexamethasone-treated animals. Conclusions Human retinal progenitor cells appear safe and efficacious in the preclinical models used here. Translational Relevance Human retinal progenitor cells could be deployed during early stages of retinal degeneration or in regions of intact retina, without adverse effects on visual function. The ability of dexamethasone to reduce baseline visual acuity in RCS dystrophic rats has important implications for the interpretation of preclinical and clinical cell transplant studies. PMID:27486556

  15. Marrow cells as progenitors of lung tissue.

    PubMed

    Fine, Alan

    2004-01-01

    There is accumulating evidence showing that marrow-derived cells can engraft as differentiated epithelial cells of various tissues, including the lung. These findings challenge long-held views regarding the basic biology of stem cells. Elucidating the fundamental mechanisms controlling these processes is the major challenge of this field. Regardless, these experiments suggest new strategies for the treatment of chronic diseases. PMID:14757420

  16. Retinal Endothelial Cell Apoptosis Stimulates Recruitment of Endothelial Progenitor Cells

    PubMed Central

    Bhatwadekar, Ashay D.; Glenn, Josephine V.; Curtis, Tim M.; Grant, Maria B.; Stitt, Alan W.; Gardiner, Tom A.

    2013-01-01

    Purpose Bone marrow–derived endothelial progenitor cells (EPCs) contribute to vascular repair although it is uncertain how local endothelial cell apoptosis influences their reparative function. This study was conducted to determine how the presence of apoptotic bodies at sites of endothelial damage may influence participation of EPCs in retinal microvascular repair. Methods Microlesions of apoptotic cell death were created in monolayers of retinal microvascular endothelial cells (RMECs) by using the photodynamic drug verteporfin. The adhesion of early-EPCs to these lesions was studied before detachment of the apoptotic cells or after their removal from the wound site. Apoptotic bodies were fed to normal RMECs and mRNA levels for adhesion molecules were analyzed. Results Endothelial lesions where apoptotic bodies were left attached at the wound site showed a fivefold enhancement in EPC recruitment (P < 0.05) compared with lesions where the apoptotic cells had been removed. In intact RMEC monolayers exposed to apoptotic bodies, expression of ICAM, VCAM, and E-selectin was upregulated by 5- to 15-fold (P < 0.05– 0.001). EPCs showed a characteristic chemotactic response (P < 0.05) to conditioned medium obtained from apoptotic bodies, whereas analysis of the medium showed significantly increased levels of VEGF, IL-8, IL-6, and TNF-α when compared to control medium; SDF-1 remained unchanged. Conclusions The data indicate that apoptotic bodies derived from retinal capillary endothelium mediate release of proangiogenic cytokines and chemokines and induce adhesion molecule expression in a manner that facilitates EPC recruitment. PMID:19474402

  17. [Wound treatment with autogenous epidermal cell expansion culture].

    PubMed

    Bonnekoh, B; Müller, R P; Mahrle, G; Steigleder, G K

    1988-11-11

    Sheets of autologous epidermal cells grown by expansion culture were used to cover small skin defects in seven patients with postoperative necroses, necroses due to temporal arteritis, varicose ulcers or after tangential excision of tattoos. Several transplantation techniques were used: backing of the cultured epithelia with vaseline gauze, Surfasoft, Adaptic, Silastic foil, culturing directly from Petriperm-foil. Meshed Silastic-foil proved to give the best support. Optimal take of the in-vitro epithelia (more than 80% of their surface area) was achieved only for fresh dermal wound-beds. The take was only moderate on chronic granulation tissue, but the transplants reduced the formation of fibrinous-necrotic material and favoured the formation of fresh granulation tissue. PMID:3181024

  18. Tissue-Derived Stem and Progenitor Cells

    PubMed Central

    Tesche, Leora J.; Gerber, David A.

    2010-01-01

    The characterization and isolation of various stem cell populations, from embryonic through tissue-derived stem cells, have led a rapid growth in the field of stem cell research. These research efforts have often been interrelated as to the markers that identify a select cell population are frequently analyzed to determine their expression in cells of distinct organs/tissues. In this review, we will expand the current state of research involving select tissue-derived stem cell populations including the liver, central nervous system, and cardiac tissues as examples of the success and challenges in this field of research. Lastly, the challenges of clinical therapies will be discussed as it applies to these unique cell populations. PMID:21048854

  19. Characterization of a Putative Receptor Binding Surface on Skint-1, a Critical Determinant of Dendritic Epidermal T Cell Selection*

    PubMed Central

    Salim, Mahboob; Knowles, Timothy J.; Hart, Rosie; Mohammed, Fiyaz; Woodward, Martin J.; Willcox, Carrie R.; Overduin, Michael; Hayday, Adrian C.; Willcox, Benjamin E.

    2016-01-01

    Dendritic epidermal T cells (DETC) form a skin-resident γδ T cell population that makes key contributions to cutaneous immune stress surveillance, including non-redundant contributions to protection from cutaneous carcinogens. How DETC become uniquely associated with the epidermis was in large part solved by the identification of Skint-1, the prototypic member of a novel B7-related multigene family. Expressed only by thymic epithelial cells and epidermal keratinocytes, Skint-1 drives specifically the development of DETC progenitors, making it the first clear candidate for a selecting ligand for non-MHC/CD1-restricted T cells. However, the molecular mechanisms underpinning Skint-1 activity are unresolved. Here, we provide evidence that DETC selection requires Skint-1 expression on the surface of thymic epithelial cells, and depends upon specific residues on the CDR3-like loop within the membrane-distal variable domain of Skint-1 (Skint-1 DV). Nuclear magnetic resonance of Skint-1 DV revealed a core tertiary structure conserved across the Skint family, but a highly distinct surface charge distribution, possibly explaining its unique function. Crucially, the CDR3-like loop formed an electrostatically distinct surface, featuring key charged and hydrophobic solvent-exposed residues, at the membrane-distal tip of DV. These results provide the first structural insights into the Skint family, identifying a putative receptor binding surface that directly implicates Skint-1 in receptor-ligand interactions crucial for DETC selection. PMID:26917727

  20. Characterization of a Putative Receptor Binding Surface on Skint-1, a Critical Determinant of Dendritic Epidermal T Cell Selection.

    PubMed

    Salim, Mahboob; Knowles, Timothy J; Hart, Rosie; Mohammed, Fiyaz; Woodward, Martin J; Willcox, Carrie R; Overduin, Michael; Hayday, Adrian C; Willcox, Benjamin E

    2016-04-22

    Dendritic epidermal T cells (DETC) form a skin-resident γδ T cell population that makes key contributions to cutaneous immune stress surveillance, including non-redundant contributions to protection from cutaneous carcinogens. How DETC become uniquely associated with the epidermis was in large part solved by the identification of Skint-1, the prototypic member of a novel B7-related multigene family. Expressed only by thymic epithelial cells and epidermal keratinocytes, Skint-1 drives specifically the development of DETC progenitors, making it the first clear candidate for a selecting ligand for non-MHC/CD1-restricted T cells. However, the molecular mechanisms underpinning Skint-1 activity are unresolved. Here, we provide evidence that DETC selection requires Skint-1 expression on the surface of thymic epithelial cells, and depends upon specific residues on the CDR3-like loop within the membrane-distal variable domain of Skint-1 (Skint-1 DV). Nuclear magnetic resonance of Skint-1 DV revealed a core tertiary structure conserved across the Skint family, but a highly distinct surface charge distribution, possibly explaining its unique function. Crucially, the CDR3-like loop formed an electrostatically distinct surface, featuring key charged and hydrophobic solvent-exposed residues, at the membrane-distal tip of DV. These results provide the first structural insights into the Skint family, identifying a putative receptor binding surface that directly implicates Skint-1 in receptor-ligand interactions crucial for DETC selection. PMID:26917727

  1. Intrinsic Age-Dependent Changes and Cell-Cell Contacts Regulate Nephron Progenitor Lifespan.

    PubMed

    Chen, Shuang; Brunskill, Eric W; Potter, S Steven; Dexheimer, Phillip J; Salomonis, Nathan; Aronow, Bruce J; Hong, Christian I; Zhang, Tongli; Kopan, Raphael

    2015-10-12

    During fetal development, nephrons of the metanephric kidney form from a mesenchymal progenitor population that differentiates en masse before or shortly after birth. We explored intrinsic and extrinsic mechanisms controlling progenitor lifespan in a transplantation assay that allowed us to compare engraftment of old and young progenitors into the same young niche. The progenitors displayed an age-dependent decrease in proliferation and concomitant increase in niche exit rates. Single-cell transcriptome profiling revealed progressive age-dependent changes, with heterogeneity increasing in older populations. Age-dependent elevation in mTor and reduction in Fgf20 could contribute to increased exit rates. Importantly, 30% of old progenitors remained in the niche for up to 1 week post engraftment, a net gain of 50% to their lifespan, but only if surrounded by young neighbors. We provide evidence in support of a model in which intrinsic age-dependent changes affect inter-progenitor interactions that drive cessation of nephrogenesis. PMID:26460946

  2. Mesp1 Marked Cardiac Progenitor Cells Repair Infarcted Mouse Hearts

    PubMed Central

    Liu, Yu; Chen, Li; Diaz, Andrea Diaz; Benham, Ashley; Xu, Xueping; Wijaya, Cori S.; Fa’ak, Faisal; Luo, Weijia; Soibam, Benjamin; Azares, Alon; Yu, Wei; Lyu, Qiongying; Stewart, M. David; Gunaratne, Preethi; Cooney, Austin; McConnell, Bradley K.; Schwartz, Robert J.

    2016-01-01

    Mesp1 directs multipotential cardiovascular cell fates, even though it’s transiently induced prior to the appearance of the cardiac progenitor program. Tracing Mesp1-expressing cells and their progeny allows isolation and characterization of the earliest cardiovascular progenitor cells. Studying the biology of Mesp1-CPCs in cell culture and ischemic disease models is an important initial step toward using them for heart disease treatment. Because of Mesp1’s transitory nature, Mesp1-CPC lineages were traced by following EYFP expression in murine Mesp1Cre/+; Rosa26EYFP/+ ES cells. We captured EYFP+ cells that strongly expressed cardiac mesoderm markers and cardiac transcription factors, but not pluripotent or nascent mesoderm markers. BMP2/4 treatment led to the expansion of EYFP+ cells, while Wnt3a and Activin were marginally effective. BMP2/4 exposure readily led EYFP+ cells to endothelial and smooth muscle cells, but inhibition of the canonical Wnt signaling was required to enter the cardiomyocyte fate. Injected mouse pre-contractile Mesp1-EYFP+ CPCs improved the survivability of injured mice and restored the functional performance of infarcted hearts for at least 3 months. Mesp1-EYFP+ cells are bona fide CPCs and they integrated well in infarcted hearts and emerged de novo into terminally differentiated cardiac myocytes, smooth muscle and vascular endothelial cells. PMID:27538477

  3. Mesp1 Marked Cardiac Progenitor Cells Repair Infarcted Mouse Hearts.

    PubMed

    Liu, Yu; Chen, Li; Diaz, Andrea Diaz; Benham, Ashley; Xu, Xueping; Wijaya, Cori S; Fa'ak, Faisal; Luo, Weijia; Soibam, Benjamin; Azares, Alon; Yu, Wei; Lyu, Qiongying; Stewart, M David; Gunaratne, Preethi; Cooney, Austin; McConnell, Bradley K; Schwartz, Robert J

    2016-01-01

    Mesp1 directs multipotential cardiovascular cell fates, even though it's transiently induced prior to the appearance of the cardiac progenitor program. Tracing Mesp1-expressing cells and their progeny allows isolation and characterization of the earliest cardiovascular progenitor cells. Studying the biology of Mesp1-CPCs in cell culture and ischemic disease models is an important initial step toward using them for heart disease treatment. Because of Mesp1's transitory nature, Mesp1-CPC lineages were traced by following EYFP expression in murine Mesp1(Cre/+); Rosa26(EYFP/+) ES cells. We captured EYFP+ cells that strongly expressed cardiac mesoderm markers and cardiac transcription factors, but not pluripotent or nascent mesoderm markers. BMP2/4 treatment led to the expansion of EYFP+ cells, while Wnt3a and Activin were marginally effective. BMP2/4 exposure readily led EYFP+ cells to endothelial and smooth muscle cells, but inhibition of the canonical Wnt signaling was required to enter the cardiomyocyte fate. Injected mouse pre-contractile Mesp1-EYFP+ CPCs improved the survivability of injured mice and restored the functional performance of infarcted hearts for at least 3 months. Mesp1-EYFP+ cells are bona fide CPCs and they integrated well in infarcted hearts and emerged de novo into terminally differentiated cardiac myocytes, smooth muscle and vascular endothelial cells. PMID:27538477

  4. Langerhans Cells Facilitate UVB-induced Epidermal Carcinogenesis

    PubMed Central

    Lewis, Julia M.; Bürgler, Christina D.; Freudzon, Marianna; Golubets, Kseniya; Gibson, Juliet F.; Filler, Renata B.; Girardi, Michael

    2015-01-01

    Ultraviolet B (UVB) light is considered the major environmental inducer of human keratinocyte DNA mutations, including within the tumor-suppressor gene p53, and chronic exposure is associated with cutaneous squamous cell carcinoma (SCC) formation. Langerhans cells (LC) comprise a dendritic network within the suprabasilar epidermis, yet the role of LC in UVB-induced carcinogenesis is largely unknown. Herein, we show that LC-intact epidermis develops UVB-induced tumors more readily than LC-deficient epidermis. While levels of epidermal cyclopyrimidine dimers (CPD) following acute UVB exposure are equivalent in the presence or absence of LC, chronic UVB-induced p53 mutant clonal islands expand more readily in association with LC which remain largely intact and are preferentially found in proximity to the expanding mutant keratinocyte populations. The observed LC facilitation of mutant p53 clonal expansion is completely αβ and γδ T-cell independent, and is associated with increased intraepidermal expression of interleukin (IL)-22 and the presence of group 3 innate lymphoid cells (ILC3). These data demonstrate that LC play a key role in UVB-induced cutaneous carcinogenesis, and suggest that LC locally stimulate keratinocyte proliferation and innate immune cells that provoke tumor outgrowth. PMID:26053049

  5. Endothelial progenitor cells accelerate the resolution of deep vein thrombosis.

    PubMed

    Li, Wen-Dong; Li, Xiao-Qiang

    2016-08-01

    Deep vein thrombosis (DVT) causes high morbidity and mortality. Successful resolution of DVT-related thrombi is the key point in the treatment of DVT. Recently, endothelial progenitor cells (EPCs) which are multipotent progenitor cells mainly residing in human bone marrow have emerged as a promising therapeutic choice for DVT-related thrombus resolution. In this review, we discussed the mobilization and homing property of EPCs into the sites of thrombosis, mechanisms of EPCs in DVT-related thrombus resolution from the aspects of promoting endothelial regeneration, revascularization, vasoactive and angiogenic factor secretion, proteinase generation, thrombus propagation and recurrence prevention, and vein wall remodeling. In addition, we also provide suggestions on EPCs as a therapeutic choice for thrombus resolution. PMID:26187355

  6. Proliferation control in neural stem and progenitor cells

    PubMed Central

    Homem, Catarina CF; Repic, Marko; Knoblich, Juergen A

    2015-01-01

    Neural circuit function can be drastically affected by variations in the number of cells that are produced during development or by a reduction in adult cell number due to disease. Unlike many other organs, the brain is unable to compensate for such changes by increasing cell numbers or altering the size of the cells. For this reason, unique cell cycle and cell growth control mechanisms operate in the developing and adult brain. In Drosophila melanogaster and mammalian neural stem and progenitor cells these mechanisms are intricately coordinated with the developmental age and the nutritional, metabolic and hormonal state of the animal. Defects in neural stem cell proliferation that result in the generation of incorrect cell numbers or defects in neural stem cell differentiation can cause microcephaly or megalencephaly. PMID:26420377

  7. Isolation and Characterization of Distal Lung Progenitor Cells

    PubMed Central

    Driscoll, Barbara; Kikuchi, Alex; Lau, Allison N.; Lee, Jooeun; Reddy, Raghava; Jesudason, Edwin; Kim, Carla F.; Warburton, David

    2013-01-01

    The majority of epithelial cells in the distal lung of rodents and humans are quiescent in vivo, yet certain cell populations retain an intrinsic capacity to proliferate and differentiate in response to lung injury or in appropriate culture settings, thus giving them properties of stem/progenitor cells. Here, we describe the isolation of two such populations from adult mouse lung: alveolar epithelial type 2 cells (AEC2), which can generate alveolar epithelial type 1 cells, and bronchioalveolar stem cells (BASCs), which in culture can reproduce themselves, as well as generate a small number of other distal lung epithelial cell types. These primary epithelial cells are typically isolated using enzyme digestion, mechanical disruption, and serial filtration. AEC2 and BASCs are distinguished from other distal lung cells by expression of specific markers as detected by fluorescence-activated cell sorting, immunohistochemistry, or a combination of both of these techniques. PMID:22610556

  8. Detection of human myeloid progenitor cells in a murine background.

    PubMed

    Carow, C E; Harrington, M A; Broxmeyer, H E

    1993-01-01

    Cell-mixing experiments were performed to determine whether human (hu) peripheral blood plasma would select for the growth of hu myeloid progenitor cells in vitro. Mixtures of hu male umbilical cord blood and murine (mu) female bone marrow (100% hu, 100% mu, 1.0% hu or 10% hu and 50% hu) were plated in methylcellulose cultures that contained either hu plasma or fetal bovine serum (FBS). Cultures were supplemented with recombinant (r) hu erythropoietin (Epo) alone or in combination with rhu granulocyte-macrophage colony stimulating factor (GM-CSF), rmuGM-CSF or rhu steel factor (SLF). DNA was extracted from day 14 colonies and clusters, and the polymerase chain reaction (PCR) was used to detect the hu Y-chromosome satellite DNA sequence. Results of these studies revealed that hu plasma used in combination with hu growth factors selected for the growth of hu progenitor cells. Mu cells grew in hu plasma only at high cell-plating concentrations. This selective effect was due to a heat labile factor or factors, since mu cells grew equally well in heat-inactivated hu plasma and FBS. Cells in individual progenitor cell colonies and clusters cultured in hu plasma contained hu Y-chromosome-specific DNA sequences that were detectable after PCR-mediated amplification, thus eliminating the need for time-consuming Southern transfer. This study describes a method whereby hu/immune-deficient mice can be screened rapidly for hu myeloid engraftment. These results also indicate that the hu identity of colonies and clusters cultured in hu plasma must be genetically confirmed, especially when hu cells may represent a low percentage of the total cells plated. PMID:7678088

  9. Mesenchymal markers on human adipose stem/progenitor cells

    PubMed Central

    Zimmerlin, Ludovic; Donnenberg, Vera S.; Rubin, J. Peter; Donnenberg, Albert D.

    2014-01-01

    The stromal-vascular fraction (SVF) of adipose tissue is a rich source of multipotent stem cells. We and others have described 3 major populations of stem/progenitor cells in this fraction, all closely associated with small blood vessels: endothelial progenitor cells (EPC, CD45−/CD31+/CD34+), pericytes (CD45−/CD31−/CD146+) and supra-adventitial adipose stromal cells (SA-ASC, CD45−/CD31−/CD146−/CD34+). EPC are luminal, pericytes are adventitial and SA-ASC surround the vessel like a sheath. The multipotency of the pericytes and SA-ASC compartments is strikingly similar to that of CD45−/CD34−/CD73+/CD105+/CD90+ bone marrow-derived mesenchymal stem cells (BM-MSC). Here we determine the extent to which this mesenchymal expression pattern is expressed on the 3 adipose stem/progenitor populations. Eight independent adipose tissue samples were analyzed in a single tube (CD105-FITC/CD73-PE/CD146-PETXR/CD14-PECY5/CD33-PECY5/CD235A-PECY5/CD31-PECY7/CD90-APC/CD34-A700/CD45-APCCY7/DAPI). Adipose EPC were highly proliferative with 14.3±2.8% (mean ± SEM) having >2N DNA. About half (53.1±7.6%) coexpressed CD73 and CD105, and 71.9±7.4% expressed CD90. Pericytes were less proliferative (8.2±3.4% >2N DNA) with a smaller proportion (29.6±6.9% CD73+/CD105+, 60.5±10.2% CD90+) expressing mesenchymal associated markers. However, the CD34+ subset of CD146+ pericytes, were both highly proliferative (15.1±3.6% with >2N DNA) and of uniform mesenchymal phenotype (93.3±3.7% CD73+/CD105+, 97.8±0.7% CD90+), suggesting transit amplifying progenitor cells. SA-ASC were the least proliferative (3.7 ± 0.8%>2N DNA) but were also highly mesenchymal in phenotype (94.4±3.2% CD73+/CD105+, 95.5±1.2% CD90+). These data imply a progenitor/progeny relationship between pericytes and SA-ASC, the most mesenchymal of SVF cells. Despite phenotypic and functional similarities to BM-MSC, SA-ASC are distinguished by CD34 expression. PMID:23184564

  10. Endothelial Progenitor Cells for Diagnosis and Prognosis in Cardiovascular Disease

    PubMed Central

    Cairo, Valentina; D'Ascola, Angela; Scuruchi, Michele; Basile, Giorgio; Mandraffino, Giuseppe

    2016-01-01

    Objective. To identify, evaluate, and synthesize evidence on the predictive power of circulating endothelial progenitor cells (EPCs) in cardiovascular disease, through a systematic review of quantitative studies. Data Sources. MEDLINE was searched using keywords related to “endothelial progenitor cells” and “endothelium” and, for the different categories, respectively, “smoking”; “blood pressure”; “diabetes mellitus” or “insulin resistance”; “dyslipidemia”; “aging” or “elderly”; “angina pectoris” or “myocardial infarction”; “stroke” or “cerebrovascular disease”; “homocysteine”; “C-reactive protein”; “vitamin D”. Study Selection. Database hits were evaluated against explicit inclusion criteria. From 927 database hits, 43 quantitative studies were included. Data Syntheses. EPC count has been suggested for cardiovascular risk estimation in the clinical practice, since it is currently accepted that EPCs can work as proangiogenic support cells, maintaining their importance as regenerative/reparative potential, and also as prognostic markers. Conclusions. EPCs showed an important role in identifying cardiovascular risk conditions, and to suggest their evaluation as predictor of outcomes appears to be reasonable in different defined clinical settings. Due to their capability of proliferation, circulation, and the development of functional progeny, great interest has been directed to therapeutic use of progenitor cells in atherosclerotic diseases. This trial is registered with registration number: Prospero CRD42015023717. PMID:26839569

  11. Role of intermediate progenitor cells in cerebral cortex development.

    PubMed

    Pontious, Adria; Kowalczyk, Tom; Englund, Chris; Hevner, Robert F

    2008-01-01

    Intermediate progenitor cells (IPCs) are a type of neurogenic transient amplifying cells in the developing cerebral cortex. IPCs divide symmetrically at basal (abventricular) positions in the neuroepithelium to produce pairs of new neurons or, in amplifying divisions, pairs of new IPCs. In contrast, radial unit progenitors (neuroepithelial cells and radial glia) divide at the apical (ventricular) surface and produce only single neurons or single IPCs by asymmetric division, or self-amplify by symmetric division. Histologically, IPCs are most prominent during the middle and late stages of neurogenesis, when they accumulate in the subventricular zone, a progenitor compartment linked to the genesis of upper neocortical layers (II-IV). Nevertheless, IPCs are present throughout cortical neurogenesis and produce neurons for all layers. In mice, changes in the abundance of IPCs caused by mutations of Pax6, Ngn2, Id4 and other genes are associated with parallel changes in cortical thickness but not surface area. In gyrencephalic brains, IPCs may play broader roles in determining not only laminar thickness, but also cortical surface area and gyral patterns. We propose that regulation of IPC genesis and amplification across developmental stages and regional subdivisions modulates laminar neurogenesis and contributes to the cytoarchitectonic differentiation of cortical areas. PMID:18075251

  12. Turning terminally differentiated skeletal muscle cells into regenerative progenitors.

    PubMed

    Wang, Heng; Lööf, Sara; Borg, Paula; Nader, Gustavo A; Blau, Helen M; Simon, András

    2015-01-01

    The ability to repeatedly regenerate limbs during the entire lifespan of an animal is restricted to certain salamander species among vertebrates. This ability involves dedifferentiation of post-mitotic cells into progenitors that in turn form new structures. A long-term enigma has been how injury leads to dedifferentiation. Here we show that skeletal muscle dedifferentiation during newt limb regeneration depends on a programmed cell death response by myofibres. We find that programmed cell death-induced muscle fragmentation produces a population of 'undead' intermediate cells, which have the capacity to resume proliferation and contribute to muscle regeneration. We demonstrate the derivation of proliferating progeny from differentiated, multinucleated muscle cells by first inducing and subsequently intercepting a programmed cell death response. We conclude that cell survival may be manifested by the production of a dedifferentiated cell with broader potential and that the diversion of a programmed cell death response is an instrument to achieve dedifferentiation. PMID:26243583

  13. Analysing human neural stem cell ontogeny by consecutive isolation of Notch active neural progenitors

    PubMed Central

    Edri, Reuven; Yaffe, Yakey; Ziller, Michael J.; Mutukula, Naresh; Volkman, Rotem; David, Eyal; Jacob-Hirsch, Jasmine; Malcov, Hagar; Levy, Carmit; Rechavi, Gideon; Gat-Viks, Irit; Meissner, Alexander; Elkabetz, Yechiel

    2015-01-01

    Decoding heterogeneity of pluripotent stem cell (PSC)-derived neural progeny is fundamental for revealing the origin of diverse progenitors, for defining their lineages, and for identifying fate determinants driving transition through distinct potencies. Here we have prospectively isolated consecutively appearing PSC-derived primary progenitors based on their Notch activation state. We first isolate early neuroepithelial cells and show their broad Notch-dependent developmental and proliferative potential. Neuroepithelial cells further yield successive Notch-dependent functional primary progenitors, from early and midneurogenic radial glia and their derived basal progenitors, to gliogenic radial glia and adult-like neural progenitors, together recapitulating hallmarks of neural stem cell (NSC) ontogeny. Gene expression profiling reveals dynamic stage-specific transcriptional patterns that may link development of distinct progenitor identities through Notch activation. Our observations provide a platform for characterization and manipulation of distinct progenitor cell types amenable for developing streamlined neural lineage specification paradigms for modelling development in health and disease. PMID:25799239

  14. Murine mammary stem/progenitor cell isolation: Different method matters?

    PubMed

    Gao, Hui; Dong, Qiaoxiang; Chen, Yuanhong; Zhang, Fuchuang; Wu, Anqi; Shi, Yuanshuo; Bandyopadhyay, Abhik; Daniel, Benjamin J; Huang, Changjiang; Sun, Lu-Zhe

    2016-01-01

    Murine mammary stem/progenitor cell isolation has been routinely used in many laboratories, yet direct comparison among different methods is lacking. In this study, we compared two frequently used digestion methods and three sets of frequently used surface markers for their efficiency in enriching mammary stem and progenitor cells in two commonly used mouse strains, C57BL/6J and FVB. Our findings revealed that the slow overnight digestion method using gentle collagenase/hyaluronidase could be easily adopted and yielded reliable and consistent results in different batches of animals. In contrast, the different fast digestion protocols, as described in published studies, yielded high percent of non-epithelial cells with very few basal epithelial cells liberated in our hands. The three sets of markers tested in our hands reveal rather equally efficiency in separating luminal and basal cells if same fluorochrome conjugations were used. However, the tendency of non-epithelial cell inclusion in the basal cell gate was highest in samples profiled by CD24/CD29 and lowest in samples profiled by CD49f/EpCAM, this is especially true in mammary cells isolated from C57BL/6J mice. This finding will have significant implication when sorted basal cells are used for subsequent gene expression analysis. PMID:26933638

  15. Tracking of Normal and Malignant Progenitor Cell Cycle Transit in a Defined Niche

    PubMed Central

    Pineda, Gabriel; Lennon, Kathleen M.; Delos Santos, Nathaniel P.; Lambert-Fliszar, Florence; Riso, Gennarina L.; Lazzari, Elisa; Marra, Marco A.; Morris, Sheldon; Sakaue-Sawano, Asako; Miyawaki, Atsushi; Jamieson, Catriona H. M.

    2016-01-01

    While implicated in therapeutic resistance, malignant progenitor cell cycle kinetics have been difficult to quantify in real-time. We developed an efficient lentiviral bicistronic fluorescent, ubiquitination-based cell cycle indicator reporter (Fucci2BL) to image live single progenitors on a defined niche coupled with cell cycle gene expression analysis. We have identified key differences in cell cycle regulatory gene expression and transit times between normal and chronic myeloid leukemia progenitors that may inform cancer stem cell eradication strategies. PMID:27041210

  16. The Antiaging Properties of Andrographis paniculata by Activation Epidermal Cell Stemness.

    PubMed

    You, Jiyoung; Roh, Kyung-Baeg; Li, Zidan; Liu, Guangrong; Tang, Jian; Shin, Seoungwoo; Park, Deokhoon; Jung, Eunsun

    2015-01-01

    Andrographis paniculata (A. paniculata, Chuanxinlian), a medicinal herb with an extremely bitter taste that is native to China and other parts of Southeast Asia, possesses immense therapeutic value; however, its therapeutic properties have rarely been applied in the field of skin care. In this study, we investigated the effect of an A. paniculata extract (APE) on human epidermal stem cells (EpSCs), and confirmed its anti-aging effect through in vitro, ex vivo, and in vivo study. An MTT assay was used to determine cell proliferation. A flow cytometric analysis, with propidium iodide, was used to evaluate the cell cycle. The expression of integrin β1 (CD29), the stem cell marker, was detected with antibodies, using flow cytometry in vitro, and immunohistochemical assays in ex vivo. Type 1 collagen and VEGF (vascular endothelial growth factor) were measured using an enzyme-linked immunosorbent assay (ELISA). During the clinical study, skin hydration, elasticity, wrinkling, sagging, and dermal density were evaluated before treatment and at four and eight weeks after the treatment with the test product (containing the APE) on the face. The proliferation of the EpSCs, treated with the APE, increased significantly. In the cell cycle analysis, the APE increased the G2/M and S stages in a dose-dependent manner. The expression of integrin β1, which is related to epidermal progenitor cell expansion, was up-regulated in the APE-treated EpSCs and skin explants. In addition, the production of VEGF in the EpSCs increased significantly in response to the APE treatment. Consistent with these results, the VEGF and APE-treated EpSCs conditioned medium enhanced the Type 1 collagen production in normal human fibroblasts (NHFs). In the clinical study, the APE improved skin hydration, dermal density, wrinkling, and sagging significantly. Our findings revealed that the APE promotes a proliferation of EpSCs, through the up-regulation of the integrin β1 and VEGF expression. The VEGF

  17. β-Cell regeneration through the transdifferentiation of pancreatic cells: Pancreatic progenitor cells in the pancreas.

    PubMed

    Kim, Hyo-Sup; Lee, Moon-Kyu

    2016-05-01

    Pancreatic progenitor cell research has been in the spotlight, as these cells have the potential to replace pancreatic β-cells for the treatment of type 1 and 2 diabetic patients with the absence or reduction of pancreatic β-cells. During the past few decades, the successful treatment of diabetes through transplantation of the whole pancreas or isolated islets has nearly been achieved. However, novel sources of pancreatic islets or insulin-producing cells are required to provide sufficient amounts of donor tissues. To overcome this limitation, the use of pancreatic progenitor cells is gaining more attention. In particular, pancreatic exocrine cells, such as duct epithelial cells and acinar cells, are attractive candidates for β-cell regeneration because of their differentiation potential and pancreatic lineage characteristics. It has been assumed that β-cell neogenesis from pancreatic progenitor cells could occur in pancreatic ducts in the postnatal stage. Several studies have shown that insulin-producing cells can arise in the duct tissue of the adult pancreas. Acinar cells also might have the potential to differentiate into insulin-producing cells. The present review summarizes recent progress in research on the transdifferentiation of pancreatic exocrine cells into insulin-producing cells, especially duct and acinar cells. PMID:27330712

  18. Evidence of progenitor cells of glandular and myoepithelial cell lineages in the human adult female breast epithelium: a new progenitor (adult stem) cell concept.

    PubMed

    Boecker, Werner; Buerger, Horst

    2003-10-01

    Although experimental data clearly confirm the existence of self-renewing mammary stem cells, the characteristics of such progenitor cells have never been satisfactorily defined. Using a double immunofluorescence technique for simultaneous detection of the basal cytokeratin 5, the glandular cytokeratins 8/18 and the myoepithelial differentiation marker smooth muscle actin (SMA), we were able to demonstrate the presence of CK5+ cells in human adult breast epithelium. These cells have the potential to differentiate to either glandular (CK8/18+) or myoepithelial cells (SMA+) through intermediary cells (CK5+ and CK8/18+ or SMA+). We therefore proceeded on the assumption that the CK5+ cells are phenotypically and behaviourally progenitor (committed adult stem) cells of human breast epithelium. Furthermore, we furnish evidence that most of these progenitor cells are located in the luminal epithelium of the ductal lobular tree. Based on data obtained in extensive analyses of proliferative breast disease lesions, we have come to regard usual ductal hyperplasia as a progenitor cell-derived lesion, whereas most breast cancers seem to evolve from differentiated glandular cells. Double immunofluorescence experiments provide a new tool to characterize phenotypically progenitor (adult stem) cells and their progenies. This model has been shown to be of great value for a better understanding not only of normal tissue regeneration but also of proliferative breast disease. Furthermore, this model provides a new tool for unravelling further the regulatory mechanisms that govern normal and pathological cell growth. PMID:14521517

  19. Epigenetic Regulation of Epidermal Stem Cell Biomarkers and Their Role in Wound Healing

    PubMed Central

    Saldanha, Sabita N.; Royston, Kendra J.; Udayakumar, Neha; Tollefsbol, Trygve O.

    2015-01-01

    As an actively renewable tissue, changes in skin architecture are subjected to the regulation of stem cells that maintain the population of cells responsible for the formation of epidermal layers. Stems cells retain their self-renewal property and express biomarkers that are unique to this population. However, differential regulation of the biomarkers can initiate the pathway of terminal cell differentiation. Although, pockets of non-clarity in stem cell maintenance and differentiation in skin still exist, the influence of epigenetics in epidermal stem cell functions and differentiation in skin homeostasis and wound healing is clearly evident. The focus of this review is to discuss the epigenetic regulation of confirmed and probable epidermal stem cell biomarkers in epidermal stratification of normal skin and in diseased states. The role of epigenetics in wound healing, especially in diseased states of diabetes and cancer, will also be conveyed. PMID:26712738

  20. Quantitative changes in gene transcription during induction of differentiation in porcine neural progenitor cells

    PubMed Central

    Yang, Jing; Gu, Ping; Menges, Steven

    2012-01-01

    Purpose Differentiation of neural stem/progenitor cells involves changes in the gene expression of these cells. Less clear is the extent to which incremental changes occur and the time course of such changes, particularly in non-rodents. Methods Using porcine genome microarrays, we analyzed changes in the expression of 23,256 genes in porcine neural progenitor cells (pNPCs) subject to two established differentiation protocols. In addition, we performed sequential quantitative assessment of a defined transcription profile consisting of 15 progenitor- and lineage-associated genes following exposure to the same treatment protocols, to examine the temporal dynamics of phenotypic changes following induction of differentiation. Immunocytochemistry was also used to examine the expression of seven of these phenotypically important genes at the protein level. Initial primary isolates were passaged four times in proliferation medium containing 20 ng/ml epidermal growth factor (EGF) and 20 ng/ml basic fibroblast growth factor (bFGF) before differentiation was induced. Differentiation was induced by medium without EGF or bFGF and containing either 10 ng/ml ciliary neurotrophic factor or 10% fetal bovine serum (FBS). Cultures were fed every two days and harvested on days 0, 1, 3, and 5 for quantitative real-time PCR. Results The microarray results illustrated and contrasted the global shifts in the porcine transcriptome associated with both treatment conditions. PCR confirmed dramatic upregulation of transcripts for myelin basic protein (up to 88 fold), claudin 11 (up to 32 fold), glial fibrillary acidic protein (GFAP; up to 26 fold), together with notable (>twofold) increases in message for microtubule associated protein 2 (MAP2) and C-X-C chemokine receptor type 4 (CXCR4), Janus kinase 1 (Jak1), signal transducer and activator of transcription 1 (STAT1), and signal transducer and activator of transcription 3 (STAT3). Transcripts for nestin and Krüppel-like factor 4 (KLF4

  1. CD133 Is a Marker For Long-Term Repopulating Murine Epidermal Stem Cells

    PubMed Central

    Charruyer, A; Strachan, LR; Yue, L; Toth, AS; Mancianti, ML; Ghadially, R

    2012-01-01

    Maintenance, repair and renewal of the epidermis are thought to depend on a pool of dedicated epidermal stem cells. Like for many somatic tissues, isolation of a nearly pure population of stem cells is a primary goal in cutaneous biology. We used a quantitative transplantation assay, using injection of keratinocytes into subcutis combined with limiting dilution analysis, to assess the long-term repopulating ability of putative murine epidermal stem populations. Putative epidermal stem cell populations were isolated by FACS sorting. The CD133+ population and the subpopulation of CD133+ cells that exhibits high mitochondrial membrane potential (DΨmhi), were enriched for long-term repopulating epidermal stem cells vs. unfractionated cells (3.9 and 5.2-fold, respectively). Evidence for self-renewal capacity was obtained by serial transplantation of long-term epidermal repopulating units derived from CD133+ and CD133+ΔΨmhi keratinocytes. CD133+ keratinocytes were multipotent and produced significantly more hair follicles than CD133− cells. CD133+ cells were a subset of the previously described integrin α6+CD34+ bulge cell population and 28.9±8.6% were label retaining cells. Thus, murine keratinocytes within the CD133+ and CD133+ΔΨmhi populations contain epidermal stem cells that regenerate epidermis for the long-term, are self-renewing, multipotent, and label-retaining cells. PMID:22763787

  2. The Earliest Thymic T Cell Progenitors Sustain B Cell and Myeloid Lineage Potentials

    PubMed Central

    Luc, Sidinh; Luis, Tiago C.; Boukarabila, Hanane; Macaulay, Iain C.; Buza-Vidas, Natalija; Bouriez-Jones, Tiphaine; Lutteropp, Michael; Woll, Petter S.; Loughran, Stephen J.; Mead, Adam J.; Hultquist, Anne; Brown, John; Mizukami, Takuo; Matsuoka, Sahoko; Ferry, Helen; Anderson, Kristina; Duarte, Sara; Atkinson, Deborah; Soneji, Shamit; Domanski, Aniela; Farley, Alison; Sanjuan-Pla, Alejandra; Carella, Cintia; Patient, Roger; de Bruijn, Marella; Enver, Tariq; Nerlov, Claus; Blackburn, Clare; Godin, Isabelle; Jacobsen, Sten Eirik W.

    2012-01-01

    The stepwise commitment from hematopoietic stem cells in the bone marrow (BM) to T lymphocyte-restricted progenitors in the thymus represents a paradigm for understanding the requirement for distinct extrinsic cues during different stages of lineage restriction from multipotent to lineage restricted progenitors. However, the commitment stage at which progenitors migrate from the BM to the thymus remains unclear. Here we provide functional and molecular evidence at the single cell level that the earliest progenitors in the neonatal thymus possessed combined granulocyte-monocyte, T and B lymphocyte, but not megakaryocyte-erythroid lineage potential. These potentials were identical to those of thymus-seeding progenitors in the BM, which were closely related at the molecular level. These findings establish the distinct lineage-restriction stage at which the T lineage commitment transits from the BM to the remote thymus. PMID:22344248

  3. Gloss, colour and grip: multifunctional epidermal cell shapes in bee- and bird-pollinated flowers.

    PubMed

    Papiorek, Sarah; Junker, Robert R; Lunau, Klaus

    2014-01-01

    Flowers bear the function of filters supporting the attraction of pollinators as well as the deterrence of floral antagonists. The effect of epidermal cell shape on the visual display and tactile properties of flowers has been evaluated only recently. In this study we quantitatively measured epidermal cell shape, gloss and spectral reflectance of flowers pollinated by either bees or birds testing three hypotheses: The first two hypotheses imply that bee-pollinated flowers might benefit from rough surfaces on visually-active parts produced by conical epidermal cells, as they may enhance the colour signal of flowers as well as the grip on flowers for bees. In contrast, bird-pollinated flowers might benefit from flat surfaces produced by flat epidermal cells, by avoiding frequent visitation from non-pollinating bees due to a reduced colour signal, as birds do not rely on specific colour parameters while foraging. Moreover, flat petal surfaces in bird-pollinated flowers may hamper grip for bees that do not touch anthers and stigmas while consuming nectar and thus, are considered as nectar thieves. Beside this, the third hypothesis implies that those flower parts which are vulnerable to nectar robbing of bee- as well as bird-pollinated flowers benefit from flat epidermal cells, hampering grip for nectar robbing bees. Our comparative data show in fact that conical epidermal cells are restricted to visually-active parts of bee-pollinated flowers, whereas robbing-sensitive parts of bee-pollinated as well as the entire floral surface of bird-pollinated flowers possess on average flat epidermal cells. However, direct correlations between epidermal cell shape and colour parameters have not been found. Our results together with published experimental studies show that epidermal cell shape as a largely neglected flower trait might act as an important feature in pollinator attraction and avoidance of antagonists, and thus may contribute to the partitioning of flower

  4. Gloss, Colour and Grip: Multifunctional Epidermal Cell Shapes in Bee- and Bird-Pollinated Flowers

    PubMed Central

    Papiorek, Sarah; Junker, Robert R.; Lunau, Klaus

    2014-01-01

    Flowers bear the function of filters supporting the attraction of pollinators as well as the deterrence of floral antagonists. The effect of epidermal cell shape on the visual display and tactile properties of flowers has been evaluated only recently. In this study we quantitatively measured epidermal cell shape, gloss and spectral reflectance of flowers pollinated by either bees or birds testing three hypotheses: The first two hypotheses imply that bee-pollinated flowers might benefit from rough surfaces on visually-active parts produced by conical epidermal cells, as they may enhance the colour signal of flowers as well as the grip on flowers for bees. In contrast, bird-pollinated flowers might benefit from flat surfaces produced by flat epidermal cells, by avoiding frequent visitation from non-pollinating bees due to a reduced colour signal, as birds do not rely on specific colour parameters while foraging. Moreover, flat petal surfaces in bird-pollinated flowers may hamper grip for bees that do not touch anthers and stigmas while consuming nectar and thus, are considered as nectar thieves. Beside this, the third hypothesis implies that those flower parts which are vulnerable to nectar robbing of bee- as well as bird-pollinated flowers benefit from flat epidermal cells, hampering grip for nectar robbing bees. Our comparative data show in fact that conical epidermal cells are restricted to visually-active parts of bee-pollinated flowers, whereas robbing-sensitive parts of bee-pollinated as well as the entire floral surface of bird-pollinated flowers possess on average flat epidermal cells. However, direct correlations between epidermal cell shape and colour parameters have not been found. Our results together with published experimental studies show that epidermal cell shape as a largely neglected flower trait might act as an important feature in pollinator attraction and avoidance of antagonists, and thus may contribute to the partitioning of flower

  5. Epidermal Merkel cells are mechanosensory cells that tune mammalian touch receptors.

    PubMed

    Maksimovic, Srdjan; Nakatani, Masashi; Baba, Yoshichika; Nelson, Aislyn M; Marshall, Kara L; Wellnitz, Scott A; Firozi, Pervez; Woo, Seung-Hyun; Ranade, Sanjeev; Patapoutian, Ardem; Lumpkin, Ellen A

    2014-05-29

    Touch submodalities, such as flutter and pressure, are mediated by somatosensory afferents whose terminal specializations extract tactile features and encode them as action potential trains with unique activity patterns. Whether non-neuronal cells tune touch receptors through active or passive mechanisms is debated. Terminal specializations are thought to function as passive mechanical filters analogous to the cochlea's basilar membrane, which deconstructs complex sounds into tones that are transduced by mechanosensory hair cells. The model that cutaneous specializations are merely passive has been recently challenged because epidermal cells express sensory ion channels and neurotransmitters; however, direct evidence that epidermal cells excite tactile afferents is lacking. Epidermal Merkel cells display features of sensory receptor cells and make 'synapse-like' contacts with slowly adapting type I (SAI) afferents. These complexes, which encode spatial features such as edges and texture, localize to skin regions with high tactile acuity, including whisker follicles, fingertips and touch domes. Here we show that Merkel cells actively participate in touch reception in mice. Merkel cells display fast, touch-evoked mechanotransduction currents. Optogenetic approaches in intact skin show that Merkel cells are both necessary and sufficient for sustained action-potential firing in tactile afferents. Recordings from touch-dome afferents lacking Merkel cells demonstrate that Merkel cells confer high-frequency responses to dynamic stimuli and enable sustained firing. These data are the first, to our knowledge, to directly demonstrate a functional, excitatory connection between epidermal cells and sensory neurons. Together, these findings indicate that Merkel cells actively tune mechanosensory responses to facilitate high spatio-temporal acuity. Moreover, our results indicate a division of labour in the Merkel cell-neurite complex: Merkel cells signal static stimuli, such as

  6. Restricted dendritic cell and monocyte progenitors in human cord blood and bone marrow

    PubMed Central

    Lee, Jaeyop; Breton, Gaëlle; Oliveira, Thiago Yukio Kikuchi; Zhou, Yu Jerry; Aljoufi, Arafat; Puhr, Sarah; Cameron, Mark J.; Sékaly, Rafick-Pierre

    2015-01-01

    In mice, two restricted dendritic cell (DC) progenitors, macrophage/dendritic progenitors (MDPs) and common dendritic progenitors (CDPs), demonstrate increasing commitment to the DC lineage, as they sequentially lose granulocyte and monocyte potential, respectively. Identifying these progenitors has enabled us to understand the role of DCs and monocytes in immunity and tolerance in mice. In humans, however, restricted monocyte and DC progenitors remain unknown. Progress in studying human DC development has been hampered by lack of an in vitro culture system that recapitulates in vivo DC hematopoiesis. Here we report a culture system that supports development of CD34+ hematopoietic stem cell progenitors into the three major human DC subsets, monocytes, granulocytes, and NK and B cells. Using this culture system, we defined the pathway for human DC development and revealed the sequential origin of human DCs from increasingly restricted progenitors: a human granulocyte-monocyte-DC progenitor (hGMDP) that develops into a human monocyte-dendritic progenitor (hMDP), which in turn develops into monocytes, and a human CDP (hCDP) that is restricted to produce the three major DC subsets. The phenotype of the DC progenitors partially overlaps with granulocyte-macrophage progenitors (GMPs). These progenitors reside in human cord blood and bone marrow but not in the blood or lymphoid tissues. PMID:25687283

  7. Bone marrow–derived progenitor cells in pulmonary fibrosis

    PubMed Central

    Hashimoto, Naozumi; Jin, Hong; Liu, Tianju; Chensue, Stephen W.; Phan, Sem H.

    2004-01-01

    The origin of fibroblasts in pulmonary fibrosis is assumed to be intrapulmonary, but their extrapulmonary origin and especially derivation from bone marrow (BM) progenitor cells has not been ruled out. To examine this possibility directly, adult mice were durably engrafted with BM isolated from transgenic mice expressing enhanced GFP. Induction of pulmonary fibrosis in such chimera mice by endotracheal bleomycin (BLM) injection caused large numbers of GFP+ cells to appear in active fibrotic lesions, while only a few GFP+ cells could be identified in control lungs. Flow-cytometric analysis of lung cells confirmed the BLM-induced increase in GFP+ cells in chimera mice and revealed a significant increase in GFP+ cells that also express type I collagen. GFP+ lung fibroblasts isolated from chimera mice expressed collagen and telomerase reverse transcriptase but not α-smooth muscle actin. Treatment of isolated GFP+ fibroblasts with TGF-β failed to induce myofibroblast differentiation. Cultured lung fibroblasts expressed the chemokine receptors CXCR4 and CCR7 and responded chemotactically to their cognate ligands, stromal cell–derived factor-1α and secondary lymphoid chemokine, respectively. Thus the collagen-producing lung fibroblasts in pulmonary fibrosis can also be derived from BM progenitor cells. PMID:14722616

  8. Endometrial regeneration and endometrial stem/progenitor cells.

    PubMed

    Gargett, Caroline E; Nguyen, Hong P T; Ye, Louie

    2012-12-01

    The functional layer of the human endometrium is a highly regenerative tissue undergoing monthly cycles of growth, differentiation and shedding during a woman's reproductive years. Fluctuating levels of circulating estrogen and progesterone orchestrate this dramatic remodeling of human endometrium. The thin inactive endometrium of postmenopausal women which resembles the permanent basal layer of cycling endometrium retains the capacity to respond to exogenous sex steroid hormones to regenerate into a thick functional endometrium capable of supporting pregnancy. Endometrial regeneration also follows parturition and endometrial resection. In non menstruating rodents, endometrial epithelium undergoes rounds of proliferation and apoptosis during estrus cycles. The recent identification of adult stem cells in both human and mouse endometrium suggests that epithelial progenitor cells and the mesenchymal stem/stromal cells have key roles in the cyclical regeneration of endometrial epithelium and stroma. This review will summarize the evidence for endometrial stem/progenitor cells, examine their role in mouse models of endometrial epithelial repair and estrogen-induced endometrial regeneration, and also describe the generation of endometrial-like epithelium from human embryonic stem cells. With markers now available for identifying endometrial mesenchymal stem/stromal cells, their possible role in gynecological diseases associated with abnormal endometrial proliferation and their potential application in cell-based therapies to regenerate reproductive and other tissues will be discussed. PMID:22847235

  9. Presence of Stem/Progenitor Cells in the Rat Penis

    PubMed Central

    Lin, Guiting; Zhang, Xiaoyu; Wang, Jianwen; Wang, Lin; Li, Huixi; Wang, Guifang; Ning, Hongxiu; Lin, Ching-Shwun; Xin, Zhongcheng

    2015-01-01

    Tissue resident stem cells are believed to exist in every organ, and their identification is commonly done using a combination of immunostaining for putative stem cell markers and label-retaining cell (LRC) strategy. In this study, we employed these approaches to identify potential stem cells in the penis. Newborn rats were intraperitoneally injected with thymidine analog, 5-ethynyl-2-deoxyuridine (EdU), and their penis was harvested at 7 h, 3 days, 1 week, and 4 weeks. It was processed for EdU stains and immunofluorescence staining for stem cell markers A2B5, PCNA, and c-kit. EdU-positive cells were counted for each time point and co-localized with each stem cell marker, then isolated and cultured in vitro followed by their characterization using flowcytometry and immunofluorescence. At 7 h post-EdU injection, 410±105.3 penile corporal cells were labeled in each cross-section (∼28%). The number of EdU-positive cells at 3 days increased to 536±115.6, while their percentage dropped to 25%. Progressively fewer EdU-positive cells were present in the sacrificed rat penis at longer time points (1 and 4 weeks). They were mainly distributed in the subtunic and perisinusoidal spaces, and defined as subtunic penile progenitor cells (STPCs) and perisinusoidal penile progenitor cells (PPCs). These cells expressed c-kit, A2B5, and PCNA. After culturing in vitro, only ∼0.324% corporal cells were EdU-labeled LRCs and expressed A2B5/PCNA. Therefore, labeling of penis cells by EdU occurred randomly, and label retaining was not associated with expression of c-kit, A2B5, or PCNA. The penile LRCs are mainly distributed within the subtunic and perisinusoidal space. PMID:25162971

  10. Single cell sorting identifies progenitor cell population from full thickness bovine articular cartilage

    PubMed Central

    Yu, Yin; Zheng, Hongjun; Buckwalter, Joseph A.; Martin, James A.

    2014-01-01

    Objective To date, no approved clinical intervention successfully prevents the progressive degradation of injured articular cartilage that leads to osteoarthritis (OA). Stem/progenitor cell populations within tissues of diarthrodial joint have shown their therapeutic potential in treating OA. However, this potential has not been fully realized due in part to the heterogeneity of these subpopulations. Characterization of clonal populations derived from a single cell may help identify more homogenous stem/progenitor populations within articular cartilage. Moreover, chondrogenic potential of clonal populations from different zones could be further examined to elucidate their differential roles in maintaining articular cartilage homeostasis. Method We combined FACS (Fluorescence-activated cell sorting) and clonogenicity screening to identify stem/progenitor cells cloned from single cells. High-efficiency colony-forming cells (HCCs) were isolated, and evaluated for stem/progenitor cell characteristics. HCCs were also isolated from different zones of articular cartilage. Their function was compared by lineage-specific gene expression, and differentiation potential. Results A difference in colony-forming efficiency was observed in terms of colony sizes. HCCs were highly clonogenic and multipotent, and overexpressed stem/progenitor cell markers. Also, proliferation and migration associated genes were over-expressed in HCCs. HCCs showed zonal differences with deep HCCs more chondrogenic and osteogenic than superficial HCCs. Conclusion Our approach is a simple yet practical way to identify homogeneous stem/progenitor cell populations with clonal origin. The discovery of progenitor cells demonstrates the intrinsic self-repairing potential of articular cartilage. Differences in differentiation potential may represent the distinct roles of superficial and deep zone stem/progenitor cells in the maintenance of articular cartilage homeostasis. PMID:25038490

  11. How do I perform hematopoietic progenitor cell selection?

    PubMed

    Avecilla, Scott T; Goss, Cheryl; Bleau, Sharon; Tonon, Jo-Ann; Meagher, Richard C

    2016-05-01

    Graft-versus-host disease remains the most important source of morbidity and mortality associated with allogeneic stem cell transplantation. The implementation of hematopoietic progenitor cell (HPC) selection is employed by some stem cell processing facilities to mitigate this complication. Current cell selection methods include reducing the number of unwanted T cells (negative selection) and/or enriching CD34+ hematopoietic stem/progenitors (positive selection) using immunomagnetic beads subjected to magnetic fields within columns to separate out targeted cells. Unwanted side effects of cell selection as a result of T-cell reduction are primary graft failure, increased infection rates, delayed immune reconstitution, possible disease relapse, and posttransplant lymphoproliferative disease. The Miltenyi CliniMACS cell isolation system is the only device currently approved for clinical use by the Food and Drug Administration. It uses magnetic microbeads conjugated with a high-affinity anti-CD34 monoclonal antibody capable of binding to HPCs in marrow, peripheral blood, or umbilical cord blood products. The system results in significantly improved CD34+ cell recoveries (50%-100%) and consistent 3-log CD3+ T-cell reductions compared to previous generations of CD34+ cell selection procedures. In this article, the CliniMACS procedure is described in greater detail and the authors provide useful insight into modifications of the system. Successful implementation of cell selection procedures can have a significant positive clinical effect by greatly increasing the pool of donors for recipients requiring transplants. However, before a program implements cell selection techniques, it is important to consider the time and financial resources required to properly and safely perform these procedures. PMID:26919388

  12. HB-EGF-Promoted Airway Smooth Muscle Cells and Their Progenitor Migration Contribute to Airway Smooth Muscle Remodeling in Asthmatic Mouse.

    PubMed

    Wang, Qing; Li, Hequan; Yao, Yinan; Lu, Guohua; Wang, Yuehong; Xia, Dajing; Zhou, Jianying

    2016-03-01

    The airway smooth muscle (ASM) cells' proliferation, migration, and their progenitor's migration are currently regarded as causative factors for ASM remodeling in asthma. Heparin-binding epidermal growth factor (HB-EGF), a potent mitogen and chemotactic factor, could promote ASM cell proliferation through MAPK pathways. In this study, we obtained primary ASM cells and their progenitors from C57BL/6 mice and went on to explore the role of HB-EGF in these cells migration and the underlying mechanisms. We found that recombinant HB-EGF (rHB-EGF) intratracheal instillation accelerated ASM layer thickening in an OVA-induced asthmatic mouse. Modified Boyden chamber assay revealed that rHB-EGF facilitate ASM cell migration in a dose-dependent manner and ASM cells from asthmatic mice had a greater migration ability than that from normal counterparts. rHB-EGF could stimulate the phosphorylation of ERK1/2 and p38 in ASM cells but further migration assay showed that only epidermal growth factor receptor inhibitor (AG1478) or p38 inhibitor (SB203580), but not ERK1/2 inhibitor (PD98059), could inhibit rHB-EGF-mediated ASM cells migration. Actin cytoskeleton experiments exhibited that rHB-EGF could cause actin stress fibers disassembly and focal adhesions formation of ASM cells through the activation of p38. Finally, airway instillation of rHB-EGF promoted the recruitment of bone marrow-derived smooth muscle progenitor cells, which were transferred via caudal vein, migrating into the airway from the circulation. These observations demonstrated that ASM remodeling in asthma might have resulted from HB-EGF-mediated ASM cells and their progenitor cells migration, via p38 MAPK-dependent actin cytoskeleton remodeling. PMID:26826248

  13. Tendon proper- and peritenon-derived progenitor cells have unique tenogenic properties

    PubMed Central

    2014-01-01

    Introduction Multipotent progenitor populations exist within the tendon proper and peritenon of the Achilles tendon. Progenitor populations derived from the tendon proper and peritenon are enriched with distinct cell types that are distinguished by expression of markers of tendon and vascular or pericyte origins, respectively. The objective of this study was to discern the unique tenogenic properties of tendon proper- and peritenon-derived progenitors within an in vitro model. We hypothesized that progenitors from each region contribute differently to tendon formation; thus, when incorporated into a regenerative model, progenitors from each region will respond uniquely. Moreover, we hypothesized that cell populations like progenitors were capable of stimulating tenogenic differentiation, so we generated conditioned media from these cell types to analyze their stimulatory potentials. Methods Isolated progenitors were seeded within fibrinogen/thrombin gel-based constructs with or without supplementation with recombinant growth/differentiation factor-5 (GDF5). Early and late in culture, gene expression of differentiation markers and matrix assembly genes was analyzed. Tendon construct ultrastructure was also compared after 45 days. Moreover, conditioned media from tendon proper-derived progenitors, peritenon-derived progenitors, or tenocytes was applied to each of the three cell types to determine paracrine stimulatory effects of the factors secreted from each of the respective cell types. Results The cell orientation, extracellular domain and fibril organization of constructs were comparable to embryonic tendon. The tendon proper-derived progenitors produced a more tendon-like construct than the peritenon-derived progenitors. Seeded tendon proper-derived progenitors expressed greater levels of tenogenic markers and matrix assembly genes, relative to peritenon-derived progenitors. However, GDF5 supplementation improved expression of matrix assembly genes in peritenon

  14. MiR-128-2 inhibits common lymphoid progenitors from developing into progenitor B cells

    PubMed Central

    Chen, Huo; Fei, Xia; Tang, YuXu; Yan, Yunqiu; Zhang, Huimin; Zhang, Jinping

    2016-01-01

    A considerable number of studies revealed that B cell development is finely regulated by transcription factors (TFs). Recent studies suggested that TFs are coordinated with microRNAs to control the development of B cells in numerous checkpoints. In the present study, we first found that miR-128-2 was differentially expressed in various immune organs and immunocytes. B cell development was inhibited in miR-128-2-overexpressed chimera and transgenic (TG) mice in bone marrow with decreased preproB, preB, proB, immature B, and recirculating B cells, as well as increased common lymphoid progenitors (CLPs). Further experiments showed that the apoptosis of CLP decreased, but proliferation was not altered in miR-128-2-overexpressed mice. Extensive studies suggested that the inhibition of apoptosis of CLP may be caused by miR-128-2 targeting A2B and MALT1, thereby increasing the phosphorylation of ERK and P38 MAPK. Such findings have prompted future investigations on the function of miR-128-2 in lymph genesis. PMID:27008703

  15. Circulating progenitor epithelial cells traffic via CXCR4/CXCL12 in response to airway injury.

    PubMed

    Gomperts, Brigitte N; Belperio, John A; Rao, P Nagesh; Randell, Scott H; Fishbein, Michael C; Burdick, Marie D; Strieter, Robert M

    2006-02-01

    Recipient airway epithelial cells are found in human sex-mismatched lung transplants, implying that circulating progenitor epithelial cells contribute to the repair of the airway epithelium. Markers of circulating progenitor epithelial cells and mechanisms for their trafficking remain to be elucidated. We demonstrate that a population of progenitor epithelial cells exists in the bone marrow and the circulation of mice that is positive for the early epithelial marker cytokeratin 5 (CK5) and the chemokine receptor CXCR4. We used a mouse model of sex-mismatched tracheal transplantation and found that CK5+ circulating progenitor epithelial cells contribute to re-epithelialization of the airway and re-establishment of the pseudostratified epithelium. The presence of CXCL12 in tracheal transplants provided a mechanism for CXCR4+ circulating progenitor epithelial cell recruitment to the airway. Depletion of CXCL12 resulted in the epithelium defaulting to squamous metaplasia, which was derived solely from the resident tissue progenitor epithelial cells. Our findings demonstrate that CK5+CXCR4+ cells are markers of circulating progenitor epithelial cells in the bone marrow and circulation and that CXCR4/CXCL12-mediated recruitment of circulating progenitor epithelial cells is necessary for the re-establishment of a normal pseudostratified epithelium after airway injury. These findings support a novel paradigm for the development of squamous metaplasia of the airway epithelium and for developing therapeutic strategies for circulating progenitor epithelial cells in airway diseases. PMID:16424223

  16. Biology of hematopoietic stem cells and progenitors: implications for clinical application.

    PubMed

    Kondo, Motonari; Wagers, Amy J; Manz, Markus G; Prohaska, Susan S; Scherer, David C; Beilhack, Georg F; Shizuru, Judith A; Weissman, Irving L

    2003-01-01

    Stem cell biology is scientifically, clinically, and politically a current topic. The hematopoietic stem cell, the common ancestor of all types of blood cells, is one of the best-characterized stem cells in the body and the only stem cell that is clinically applied in the treatment of diseases such as breast cancer, leukemias, and congenital immunodeficiencies. Multicolor cell sorting enables the purification not only of hematopoietic stem cells, but also of their downstream progenitors such as common lymphoid progenitors and common myeloid progenitors. Recent genetic approaches including gene chip technology have been used to elucidate the gene expression profile of hematopoietic stem cells and other progenitors. Although the mechanisms that control self-renewal and lineage commitment of hematopoietic stem cells are still ambiguous, recent rapid advances in understanding the biological nature of hematopoietic stem and progenitor cells have broadened the potential application of these cells in the treatment of diseases. PMID:12615892

  17. Epidermal Viral Immunity Induced by CD8α+ Dendritic Cells But Not by Langerhans Cells

    NASA Astrophysics Data System (ADS)

    Allan, Rhys S.; Smith, Chris M.; Belz, Gabrielle T.; van Lint, Allison L.; Wakim, Linda M.; Heath, William R.; Carbone, Francis R.

    2003-09-01

    The classical paradigm for dendritic cell function derives from the study of Langerhans cells, which predominate within skin epidermis. After an encounter with foreign agents, Langerhans cells are thought to migrate to draining lymph nodes, where they initiate T cell priming. Contrary to this, we show here that infection of murine epidermis by herpes simplex virus did not result in the priming of virus-specific cytotoxic T lymphocytes by Langerhans cells. Rather, the priming response required a distinct CD8α+ dendritic cell subset. Thus, the traditional view of Langerhans cells in epidermal immunity needs to be revisited to accommodate a requirement for other dendritic cells in this response.

  18. Role of stem and progenitor cells in postmyocardial infarction patients.

    PubMed

    Liu, X; Dauwe, D; Patel, A; Janssens, S

    2009-04-01

    Despite state-of-the-art therapy, clinical outcome remains poor in myocardial infarction (MI) patients with reduced left ventricular (LV) function. Stem cell-mediated repair of the damaged heart is a promising new development in cardiovascular medicine. Embryonic stem cells and adult progenitor cells have been extensively studied for their capacity to improve LV function recovery in preclinical MI models but underlying mechanisms remain incompletely understood. Recent placebo-controlled, randomized bone marrow cell transfer trials in MI patients have shown mixed results with cell-mediated effects on global or regional LV function recovery of variable magnitude and duration. There is now growing consensus that the observed effects of bone marrow-(BM)-derived progenitor cell transfer, as applied in post-MI patients thus far, occur independently of cardiomyocyte formation. Subgroup and meta-analysis of currently available randomized and observational pilot trials have highlighted limitations of current cell-based cardiac repair and provided suggestions for future focused clinical trial design. However, the two most recently reported randomized clinical trials failed to confirm a significant biological effect. A better understanding of underlying molecular mechanisms and modalities of cell-based repair is therefore mandatory to facilitate translation of innovative cell-mediated therapies for functional recovery after MI in the years to come. Rapidly growing insights in the biology of cardiac resident cells and technological advances in generation of patient-specific induced pluripotent stem cells may hold great promise to accomplish cardio-myogenesis and directly restore contractile force generation capacity. PMID:19274031

  19. Circulating Progenitor Cells in Regenerative Technologies: A Realistic Strategy in Bone Regeneration?

    PubMed Central

    Chang, Jessica B.; Lee, Justine C.

    2016-01-01

    Strategies in skeletal regeneration research have been primarily focused on optimization of three components: cellular progenitors, biomaterials, and growth factors. With the increased understanding that circulating progenitor cells exist in peripheral blood, the question arises whether such cell types would allow for adequate osteogenesis and mineralization. In this review, we discuss the current literature on circulating progenitor cells in in vitro and in vivo studies on bone regeneration. PMID:27331195

  20. In Vitro Modeling of Brain Progenitor Cell Development under the Effect of Environmental Factors.

    PubMed

    Kuvacheva, N V; Morgun, A V; Komleva, Yu K; Khilazheva, E D; Gorina, Ya V; Lopatina, O L; Arutyunyan, S A; Salmina, A B

    2015-08-01

    We studied in vitro development of brain progenitor cells isolated from healthy 7-9-month-old Wistar rats and rats with experimental Alzheimer's disease kept under standard conditions and in enriched (multistimulus) environment in vivo. Progenitor cells from healthy animals more rapidly formed neurospheres. Considerable changes at the early stages of in vitro development of brain progenitor cells were observed in both groups kept in enriched environment. PMID:26395632

  1. Latent progenitor cells as potential regulators for tympanic membrane regeneration

    NASA Astrophysics Data System (ADS)

    Kim, Seung Won; Kim, Jangho; Seonwoo, Hoon; Jang, Kyung-Jin; Kim, Yeon Ju; Lim, Hye Jin; Lim, Ki-Taek; Tian, Chunjie; Chung, Jong Hoon; Choung, Yun-Hoon

    2015-06-01

    Tympanic membrane (TM) perforation, in particular chronic otitis media, is one of the most common clinical problems in the world and can present with sensorineural healing loss. Here, we explored an approach for TM regeneration where the latent progenitor or stem cells within TM epithelial layers may play an important regulatory role. We showed that potential TM stem cells present highly positive staining for epithelial stem cell markers in all areas of normal TM tissue. Additionally, they are present at high levels in perforated TMs, especially in proximity to the holes, regardless of acute or chronic status, suggesting that TM stem cells may be a potential factor for TM regeneration. Our study suggests that latent TM stem cells could be potential regulators of regeneration, which provides a new insight into this clinically important process and a potential target for new therapies for chronic otitis media and other eardrum injuries.

  2. Epidermal Micrografts Produced via an Automated and Minimally Invasive Tool Form at the Dermal/Epidermal Junction and Contain Proliferative Cells That Secrete Wound Healing Growth Factors

    PubMed Central

    Osborne, Sandra N.; Schmidt, Marisa A.; Derrick, Kathleen; Harper, John R.

    2015-01-01

    ABSTRACT OBJECTIVE: The aim of this scientific study was to assess epidermal micrografts for formation at the dermal-epidermal (DE) junction, cellular outgrowth, and growth factor secretion. Epidermal harvesting is an autologous option that removes only the superficial epidermal layer of the skin, considerably limiting donor site damage and scarring. Use of epidermal grafting in wound healing has been limited because of tedious, time-consuming, and inconsistent methodologies. Recently, a simplified, automated epidermal harvesting tool (CelluTome Epidermal Harvesting System; Kinetic Concepts Inc, San Antonio, Texas) that applies heat and suction concurrently to produce epidermal micrografts has become commercially available. The new technique of epidermal harvesting was shown to create viable micrografts with minimal patient discomfort and no donor-site scarring. DESIGN: This study was a prospective institutional review board–approved healthy human study. SETTING: This study was conducted at the multispecialty research facility, Clinical Trials of Texas, Inc, in San Antonio, Texas. PATIENTS: The participants were 15 healthy human volunteers. RESULTS: Epidermal micrografts formed at the DE junction, and migratory basal layer keratinocytes and melanocytes were proliferative in culture. Basement membrane–specific collagen type IV was also found to be present in the grafts, suggesting that the combination of heat and vacuum might cause partial delamination of the basement membrane. Viable basal cells actively secreted key growth factors important for modulating wound healing responses, including vascular endothelial growth factor, hepatocyte growth factor, granulocyte colony-stimulating factor, platelet-derived growth factor, and transforming growth factor α. CONCLUSIONS: Harvested epidermal micrografts retained their original keratinocyte structure, which is critical for potential re-epithelialization and repigmentation of a wound environment. PMID:26258460

  3. 5-azacytidine promotes terminal differentiation of hepatic progenitor cells.

    PubMed

    He, Yun; Cui, Jiejie; He, Tongchuan; Bi, Yang

    2015-08-01

    5-azacytidine (5-azaC) is known to induce cardiomyocyte differentiation. However, its function in hepatocyte differentiation is unclear. The present study investigated the in vitro capability of 5-azaC to promote maturation and differentiation of mouse embryonic hepatic progenitor cells, with the aim of developing an approach for improving hepatic differentiation. Mouse embryonic hepatic progenitor cells (HP14.5 cells) were treated with 5-azaC at concentrations from 0 to 20 μmol/l, in addition to hepatocyte induction culture medium. Hepatocyte induction medium induces HP14.5 cell differentiation. 5-azaC may enhance the albumin promotor-driven Gaussia luciferase (ALB-GLuc) activity in induced HP14.5 cells. In the present study 2 μmol/l was found to be the optimum concentration with which to achieve this. The expression of hepatocyte-associated factors was not significantly different between the group treated with 5-azaC alone and the control group. The mRNA levels of ALB; cytokeratin 18 (CK18); tyrosine aminotransferase (TAT); and cytochrome p450, family 1, member A1 (CYP1A1); in addition to the protein levels of ALB, CK18 and uridine diphosphate glucuronyltransferase 1A (UGT1A) in the induced group with 5-azaC, were higher than those in the induced group without 5-azaC, although no significant differences were detected in expression of the hepatic stem cell markers, DLK and α-fetoprotein, between the two groups. Treatment with 5-azaC alone did not affect glycogen synthesis or indocyanine green (ICG) metabolic function in HP14.5 cells, although it significantly increased ICG uptake and periodic acid-Schiff-positive cell numbers amongst HP14.5 cells. Therefore, the present study demonstrated that treatment with 5-azaC alone exerted no effects on the maturation and differentiation of HP14.5 cells. However, 5-azaC exhibited a synergistic effect on the terminal differentiation of induced hepatic progenitor cells in association with a hepatic induction medium. PMID

  4. Stem cell biology is population biology: differentiation of hematopoietic multipotent progenitors to common lymphoid and myeloid progenitors

    PubMed Central

    2013-01-01

    The hematopoietic stem cell (HSC) system is a demand control system, with the demand coming from the organism, since the products of the common myeloid and lymphoid progenitor (CMP, CLP respectively) cells are essential for activity and defense against disease. We show how ideas from population biology (combining population dynamics and evolutionary considerations) can illuminate the feedback control of the HSC system by the fully differentiated products, which has recently been verified experimentally. We develop models for the penultimate differentiation of HSC Multipotent Progenitors (MPPs) into CLP and CMP and introduce two concepts from population biology into stem cell biology. The first concept is the Multipotent Progenitor Commitment Response (MPCR) which is the probability that a multipotent progenitor cell follows a CLP route rather than a CMP route. The second concept is the link between the MPCR and a measure of Darwinian fitness associated with organismal performance and the levels of differentiated lymphoid and myeloid cells. We show that many MPCRs are consistent with homeostasis, but that they will lead to different dynamics of cells and signals following a wound or injury and thus have different consequences for Darwinian fitness. We show how coupling considerations of life history to dynamics of the HSC system and its products allows one to compute the selective pressures on cellular processes. We discuss ways that this framework can be used and extended. PMID:23327512

  5. A Novel Approach for Amplification and Purification of Mouse Oligodendrocyte Progenitor Cells.

    PubMed

    Yang, Junlin; Cheng, Xuejun; Shen, Jiaxi; Xie, Binghua; Zhao, Xiaofeng; Zhang, Zunyi; Cao, Qilin; Shen, Ying; Qiu, Mengsheng

    2016-01-01

    Although transgenic and knockout mice are widely used to study the specification and differentiation of oligodendrocyte precursor cells (OPCs), mouse primary OPCs are difficult to be purified and maintained, and many in vitro studies have to resort to rat OPCs as substitutes. In this study, we reported that mouse O4 negative early-stage OPCs can be obtained by culturing cortical tissue blocks, and the simultaneous treatment of OPCs with Platelet Derived Growth Factor-AA (PDGFaa), basic fibroblast growth factor (bFGF), and epidermal growth factor (EGF) is the key for the propagation of mouse OPCs in culture. EGF was found to be a potent mitogen for OPCs and cooperate with PDGFaa to extend cell division and inhibit their differentiation. EGF also collaborates with PDGFaa and bFGF to convert bipolar or tripolar OPCs to more vital fibroblast-like OPCs without compromising their oligodendrocyte differentiation potential. In addition, EGF promoted the survival and proliferation of glial progenitor cells (GPCs) derived from primary OPC cultures, and a mixture of GPCs and OPCs can be obtained and propagated in the presence of EGF, bFGF, and PDGFaa. Once EGF is withdrawn, GPC population decreased sharply and fibroblast-like OPCs changed into typical OPCs morphology, then homogeneous OPCs were obtained subsequently. PMID:27597818

  6. A Novel Approach for Amplification and Purification of Mouse Oligodendrocyte Progenitor Cells

    PubMed Central

    Yang, Junlin; Cheng, Xuejun; Shen, Jiaxi; Xie, Binghua; Zhao, Xiaofeng; Zhang, Zunyi; Cao, Qilin; Shen, Ying; Qiu, Mengsheng

    2016-01-01

    Although transgenic and knockout mice are widely used to study the specification and differentiation of oligodendrocyte precursor cells (OPCs), mouse primary OPCs are difficult to be purified and maintained, and many in vitro studies have to resort to rat OPCs as substitutes. In this study, we reported that mouse O4 negative early-stage OPCs can be obtained by culturing cortical tissue blocks, and the simultaneous treatment of OPCs with Platelet Derived Growth Factor-AA (PDGFaa), basic fibroblast growth factor (bFGF), and epidermal growth factor (EGF) is the key for the propagation of mouse OPCs in culture. EGF was found to be a potent mitogen for OPCs and cooperate with PDGFaa to extend cell division and inhibit their differentiation. EGF also collaborates with PDGFaa and bFGF to convert bipolar or tripolar OPCs to more vital fibroblast-like OPCs without compromising their oligodendrocyte differentiation potential. In addition, EGF promoted the survival and proliferation of glial progenitor cells (GPCs) derived from primary OPC cultures, and a mixture of GPCs and OPCs can be obtained and propagated in the presence of EGF, bFGF, and PDGFaa. Once EGF is withdrawn, GPC population decreased sharply and fibroblast-like OPCs changed into typical OPCs morphology, then homogeneous OPCs were obtained subsequently. PMID:27597818

  7. ECM-Dependence of Endothelial Progenitor Cell Features.

    PubMed

    Siavashi, Vahid; Nassiri, Seyed Mahdi; Rahbarghazi, Reza; Vafaei, Rana; Sariri, Reyhaneh

    2016-08-01

    Preserving self-renewal, multipotent capacity, and large-scale expansion of highly functional progenitor cells, including endothelial progenitor cells (EPCs), is a controversial issue. These current limitations, therefore, raise the need of developing promising in vitro conditions for prolonged expansion of EPCs without loss of their stemness feature. In the current study, the possible role of three different natural extracellular substrates, including collagen, gelatin, and fibronectin, on multiple parameters of EPCs such as cell morphology, phenotype, clonogenic, and vasculogenic properties was scrutinized. Next, EPCs from GFP-positive mice were pre-expanded on each of these ECM substrates and then systemically transplanted into sublethaly irradiated mice to analyze the potency of these cells for marrow reconstitution. Our results revealed considerable promise for fibronectin for EPC expansion with maintenance of stemness characteristics, whereas gelatin and collagen matrices directed the cells toward a mature endothelial phenotype. Transplantation of EPCs pre-expanded on fibronectin resulted in widespread distribution and appropriate engraftment to various tissues with habitation in close association with the microvasculature. In addition, fibronectin pre-expanded cells were gradually enriched in the bone marrow after transplantation, resulting in marrow repopulation and hematologic recovery, leading to improved survival of recipient mice whereas gelatin- and collagen-expanded cells failed to reconstitute the bone marrow. This study demonstrated that, cell characteristics of in vitro expanded EPCs are determined by the subjacent matrix. Fibronectin-expanded EPCs are heralded as a source of great promise for bone marrow reconstitution and neo-angiogenesis in therapeutic bone marrow transplantation. J. Cell. Biochem. 117: 1934-1946, 2016. © 2016 Wiley Periodicals, Inc. PMID:26756870

  8. Perivascular support of human hematopoietic stem/progenitor cells

    PubMed Central

    Corselli, Mirko; Chin, Chee Jia; Parekh, Chintan; Sahaghian, Arineh; Wang, Wenyuan; Ge, Shundi; Evseenko, Denis; Wang, Xiaoyan; Montelatici, Elisa; Lazzari, Lorenza; Crooks, Gay M.

    2013-01-01

    Hematopoietic stem and progenitor cells (HSPCs) emerge and develop adjacent to blood vessel walls in the yolk sac, aorta-gonad-mesonephros region, embryonic liver, and fetal bone marrow. In adult mouse bone marrow, perivascular cells shape a “niche” for HSPCs. Mesenchymal stem/stromal cells (MSCs), which support hematopoiesis in culture, are themselves derived in part from perivascular cells. In order to define their direct role in hematopoiesis, we tested the ability of purified human CD146+ perivascular cells, as compared with unfractionated MSCs and CD146− cells, to sustain human HSPCs in coculture. CD146+ perivascular cells support the long-term persistence, through cell-to-cell contact and at least partly via Notch activation, of human myelolymphoid HSPCs able to engraft primary and secondary immunodeficient mice. Conversely, unfractionated MSCs and CD146− cells induce differentiation and compromise ex vivo maintenance of HSPCs. Moreover, CD146+ perivascular cells express, natively and in culture, molecular markers of the vascular hematopoietic niche. Unexpectedly, this dramatic, previously undocumented ability to support hematopoietic stem cells is present in CD146+ perivascular cells extracted from the nonhematopoietic adipose tissue. PMID:23412095

  9. Hypothyroidism Impairs Human Stem Cell-Derived Pancreatic Progenitor Cell Maturation in Mice.

    PubMed

    Bruin, Jennifer E; Saber, Nelly; O'Dwyer, Shannon; Fox, Jessica K; Mojibian, Majid; Arora, Payal; Rezania, Alireza; Kieffer, Timothy J

    2016-05-01

    Pancreatic progenitors derived from human embryonic stem cells (hESCs) are a potential source of transplantable cells for treating diabetes and are currently being tested in clinical trials. Yet, how the milieu of pancreatic progenitor cells, including exposure to different factors after transplant, may influence their maturation remains unclear. Here, we examined the effect of thyroid dysregulation on the development of hESC-derived progenitor cells in vivo. Hypothyroidism was generated in SCID-beige mice using an iodine-deficient diet containing 0.15% propyl-2-thiouracil, and hyperthyroidism was generated by addition of L-thyroxine (T4) to drinking water. All mice received macroencapsulated hESC-derived progenitor cells, and thyroid dysfunction was maintained for the duration of the study ("chronic") or for 4 weeks posttransplant ("acute"). Acute hyperthyroidism did not affect graft function, but acute hypothyroidism transiently impaired human C-peptide secretion at 16 weeks posttransplant. Chronic hypothyroidism resulted in severely blunted basal human C-peptide secretion, impaired glucose-stimulated insulin secretion, and elevated plasma glucagon levels. Grafts from chronic hypothyroid mice contained fewer β-cells, heterogenous MAFA expression, and increased glucagon(+) and ghrelin(+) cells compared to grafts from euthyroid mice. Taken together, these data suggest that long-term thyroid hormone deficiency may drive the differentiation of human pancreatic progenitor cells toward α- and ε-cell lineages at the expense of β-cell formation. PMID:26740603

  10. Mutant p63 causes defective expansion of ectodermal progenitor cells and impaired FGF signalling in AEC syndrome

    PubMed Central

    Ferone, Giustina; Thomason, Helen A; Antonini, Dario; De Rosa, Laura; Hu, Bing; Gemei, Marica; Zhou, Huiqing; Ambrosio, Raffaele; Rice, David P; Acampora, Dario; van Bokhoven, Hans; Del Vecchio, Luigi; Koster, Maranke I; Tadini, Gianluca; Spencer-Dene, Bradley; Dixon, Michael; Dixon, Jill; Missero, Caterina

    2012-01-01

    Ankyloblepharon-ectodermal defects-cleft lip/palate (AEC) syndrome, which is characterized by cleft palate and severe defects of the skin, is an autosomal dominant disorder caused by mutations in the gene encoding transcription factor p63. Here, we report the generation of a knock-in mouse model for AEC syndrome (p63+/L514F) that recapitulates the human disorder. The AEC mutation exerts a selective dominant-negative function on wild-type p63 by affecting progenitor cell expansion during ectodermal development leading to a defective epidermal stem cell compartment. These phenotypes are associated with impairment of fibroblast growth factor (FGF) signalling resulting from reduced expression of Fgfr2 and Fgfr3, direct p63 target genes. In parallel, a defective stem cell compartment is observed in humans affected by AEC syndrome and in Fgfr2b−/− mice. Restoring Fgfr2b expression in p63+/L514F epithelial cells by treatment with FGF7 reactivates downstream mitogen-activated protein kinase signalling and cell proliferation. These findings establish a functional link between FGF signalling and p63 in the expansion of epithelial progenitor cells and provide mechanistic insights into the pathogenesis of AEC syndrome. PMID:22247000

  11. From Here to There, Progenitor Cells and Stem Cells Are Everywhere in Lung Vascular Remodeling.

    PubMed

    Heise, Rebecca L; Link, Patrick A; Farkas, Laszlo

    2016-01-01

    The field of stem cell biology, cell therapy, and regenerative medicine has expanded almost exponentially, in the last decade. Clinical trials are evaluating the potential therapeutic use of stem cells in many adult and pediatric lung diseases with vascular component, such as bronchopulmonary dysplasia (BPD), chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), or pulmonary arterial hypertension (PAH). Extensive research activity is exploring the lung resident and circulating progenitor cells and their contribution to vascular complications of chronic lung diseases, and researchers hope to use resident or circulating stem/progenitor cells to treat chronic lung diseases and their vascular complications. It is becoming more and more clear that progress in mechanobiology will help to understand the various influences of physical forces and extracellular matrix composition on the phenotype and features of the progenitor cells and stem cells. The current review provides an overview of current concepts in the field. PMID:27583245

  12. From Here to There, Progenitor Cells and Stem Cells Are Everywhere in Lung Vascular Remodeling

    PubMed Central

    Heise, Rebecca L.; Link, Patrick A.; Farkas, Laszlo

    2016-01-01

    The field of stem cell biology, cell therapy, and regenerative medicine has expanded almost exponentially, in the last decade. Clinical trials are evaluating the potential therapeutic use of stem cells in many adult and pediatric lung diseases with vascular component, such as bronchopulmonary dysplasia (BPD), chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), or pulmonary arterial hypertension (PAH). Extensive research activity is exploring the lung resident and circulating progenitor cells and their contribution to vascular complications of chronic lung diseases, and researchers hope to use resident or circulating stem/progenitor cells to treat chronic lung diseases and their vascular complications. It is becoming more and more clear that progress in mechanobiology will help to understand the various influences of physical forces and extracellular matrix composition on the phenotype and features of the progenitor cells and stem cells. The current review provides an overview of current concepts in the field. PMID:27583245

  13. Comparative Quantification of the Surfaceome of Human Multipotent Mesenchymal Progenitor Cells

    PubMed Central

    Holley, Rebecca J.; Tai, Guangping; Williamson, Andrew J.K.; Taylor, Samuel; Cain, Stuart A.; Richardson, Stephen M.; Merry, Catherine L.R.; Whetton, Anthony D.; Kielty, Cay M.; Canfield, Ann E.

    2015-01-01

    Summary Mesenchymal progenitor cells have great therapeutic potential, yet incomplete characterization of their cell-surface interface limits their clinical exploitation. We have employed subcellular fractionation with quantitative discovery proteomics to define the cell-surface interface proteome of human bone marrow mesenchymal stromal/stem cells (MSCs) and human umbilical cord perivascular cells (HUCPVCs). We compared cell-surface-enriched fractions from MSCs and HUCPVCs (three donors each) with adult mesenchymal fibroblasts using eight-channel isobaric-tagging mass spectrometry, yielding relative quantification on >6,000 proteins with high confidence. This approach identified 186 upregulated mesenchymal progenitor biomarkers. Validation of 10 of these markers, including ROR2, EPHA2, and PLXNA2, confirmed upregulated expression in mesenchymal progenitor populations and distinct roles in progenitor cell proliferation, migration, and differentiation. Our approach has delivered a cell-surface proteome repository that now enables improved selection and characterization of human mesenchymal progenitor populations. PMID:25684225

  14. Altered gene products involved in the malignant reprogramming of cancer stem/progenitor cells and multitargeted therapies

    PubMed Central

    Mimeault, Murielle; Batra, Surinder K.

    2013-01-01

    Recent studies in the field of cancer stem cells have revealed that the alterations in key gene products involved in the epithelial-mesenchymal transition (EMT) program, altered metabolic pathways such as enhanced glycolysis, lipogenesis and/or autophagy and treatment resistance may occur in cancer stem/progenitor cells and their progenies during cancer progression. Particularly, the sustained activation of diverse developmental cascades such as hedgehog, epidermal growth factor receptor (EGFR), Wnt/β-catenin, Notch, transforming growth factor-β (TGF-β)/TGF-βR receptors and/or stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) can play critical functions for high self-renewal potential, survival, invasion and metastases of cancer stem/progenitor cells and their progenies. It has also been observed that cancer cells may be reprogrammed to re-express different pluripotency-associated stem cell-like markers such as Myc, Oct-3/4, Nanog and Sox-2 along the EMT process and under stressful and hypoxic conditions. Moreover, the enhanced expression and/or activities of some drug resistance-associated molecules such as Bcl-2, Akt/molecular target of rapamycin (mTOR), nuclear factor-kappaB (NF-κB), hypoxia-inducible factors (HIFs), macrophage inhibitory cytokine-1 (MIC-1) and ATP-binding cassette (ABC) multidrug transporters frequently occur in cancer cells during cancer progression and metastases. These molecular events may cooperate for the survival and acquisition of a more aggressive and migratory behavior by cancer stem/progenitor cells and their progenies during cancer transition to metastatic and recurrent disease states. Of therapeutic interest, these altered gene products may also be exploited as molecular biomarkers and therapeutic targets to develop novel multitargeted strategies for improving current cancer therapies and preventing disease relapse. PMID:23994756

  15. Functional Genetic Targeting of Embryonic Kidney Progenitor Cells Ex Vivo

    PubMed Central

    Junttila, Sanna; Saarela, Ulla; Halt, Kimmo; Manninen, Aki; Pärssinen, Heikki; Lecca, M. Rita; Brändli, André W.; Sims-Lucas, Sunder; Skovorodkin, Ilya

    2015-01-01

    The embryonic mammalian metanephric mesenchyme (MM) is a unique tissue because it is competent to generate the nephrons in response to Wnt signaling. An ex vivo culture in which the MM is separated from the ureteric bud (UB), the natural inducer, can be used as a classic tubule induction model for studying nephrogenesis. However, technological restrictions currently prevent using this model to study the molecular genetic details before or during tubule induction. Using nephron segment-specific markers, we now show that tubule induction in the MM ex vivo also leads to the assembly of highly segmented nephrons. This induction capacity was reconstituted when MM tissue was dissociated into a cell suspension and then reaggregated (drMM) in the presence of human recombinant bone morphogenetic protein 7/human recombinant fibroblast growth factor 2 for 24 hours before induction. Growth factor–treated drMM also recovered the capacity for organogenesis when recombined with the UB. Cell tracking and time-lapse imaging of chimeric drMM cultures indicated that the nephron is not derived from a single progenitor cell. Furthermore, viral vector-mediated transduction of green fluorescent protein was much more efficient in dissociated MM cells than in intact mesenchyme, and the nephrogenic competence of transduced drMM progenitor cells was preserved. Moreover, drMM cells transduced with viral vectors mediating Lhx1 knockdown were excluded from the nephric tubules, whereas cells transduced with control vectors were incorporated. In summary, these techniques allow reproducible cellular and molecular examinations of the mechanisms behind nephrogenesis and kidney organogenesis in an ex vivo organ culture/organoid setting. PMID:25201883

  16. Multipotent adult progenitor cells on an allograft scaffold facilitate the bone repair process

    PubMed Central

    LoGuidice, Amanda; Houlihan, Alison; Deans, Robert

    2016-01-01

    Multipotent adult progenitor cells are a recently described population of stem cells derived from the bone marrow stroma. Research has demonstrated the potential of multipotent adult progenitor cells for treating ischemic injury and cardiovascular repair; however, understanding of multipotent adult progenitor cells in orthopedic applications remains limited. In this study, we evaluate the osteogenic and angiogenic capacity of multipotent adult progenitor cells, both in vitro and loaded onto demineralized bone matrix in vivo, with comparison to mesenchymal stem cells, as the current standard. When compared to mesenchymal stem cells, multipotent adult progenitor cells exhibited a more robust angiogenic protein release profile in vitro and developed more extensive vasculature within 2 weeks in vivo. The establishment of this vascular network is critical to the ossification process, as it allows nutrient exchange and provides an influx of osteoprogenitor cells to the wound site. In vitro assays confirmed the multipotency of multipotent adult progenitor cells along mesodermal lineages and demonstrated the enhanced expression of alkaline phosphatase and production of calcium-containing mineral deposits by multipotent adult progenitor cells, necessary precursors for osteogenesis. In combination with a demineralized bone matrix scaffold, multipotent adult progenitor cells demonstrated enhanced revascularization and new bone formation in vivo in an orthotopic defect model when compared to mesenchymal stem cells on demineralized bone matrix or demineralized bone matrix–only control groups. The potent combination of angiogenic and osteogenic properties provided by multipotent adult progenitor cells appears to create a synergistic amplification of the bone healing process. Our results indicate that multipotent adult progenitor cells have the potential to better promote tissue regeneration and healing and to be a functional cell source for use in orthopedic applications

  17. Multipotent adult progenitor cells on an allograft scaffold facilitate the bone repair process.

    PubMed

    LoGuidice, Amanda; Houlihan, Alison; Deans, Robert

    2016-01-01

    Multipotent adult progenitor cells are a recently described population of stem cells derived from the bone marrow stroma. Research has demonstrated the potential of multipotent adult progenitor cells for treating ischemic injury and cardiovascular repair; however, understanding of multipotent adult progenitor cells in orthopedic applications remains limited. In this study, we evaluate the osteogenic and angiogenic capacity of multipotent adult progenitor cells, both in vitro and loaded onto demineralized bone matrix in vivo, with comparison to mesenchymal stem cells, as the current standard. When compared to mesenchymal stem cells, multipotent adult progenitor cells exhibited a more robust angiogenic protein release profile in vitro and developed more extensive vasculature within 2 weeks in vivo. The establishment of this vascular network is critical to the ossification process, as it allows nutrient exchange and provides an influx of osteoprogenitor cells to the wound site. In vitro assays confirmed the multipotency of multipotent adult progenitor cells along mesodermal lineages and demonstrated the enhanced expression of alkaline phosphatase and production of calcium-containing mineral deposits by multipotent adult progenitor cells, necessary precursors for osteogenesis. In combination with a demineralized bone matrix scaffold, multipotent adult progenitor cells demonstrated enhanced revascularization and new bone formation in vivo in an orthotopic defect model when compared to mesenchymal stem cells on demineralized bone matrix or demineralized bone matrix-only control groups. The potent combination of angiogenic and osteogenic properties provided by multipotent adult progenitor cells appears to create a synergistic amplification of the bone healing process. Our results indicate that multipotent adult progenitor cells have the potential to better promote tissue regeneration and healing and to be a functional cell source for use in orthopedic applications. PMID

  18. Cis-regulatory mechanisms governing stem and progenitor cell transitions

    PubMed Central

    Johnson, Kirby D.; Kong, Guangyao; Gao, Xin; Chang, Yuan-I; Hewitt, Kyle J.; Sanalkumar, Rajendran; Prathibha, Rajalekshmi; Ranheim, Erik A.; Dewey, Colin N.; Zhang, Jing; Bresnick, Emery H.

    2015-01-01

    Cis-element encyclopedias provide information on phenotypic diversity and disease mechanisms. Although cis-element polymorphisms and mutations are instructive, deciphering function remains challenging. Mutation of an intronic GATA motif (+9.5) in GATA2, encoding a master regulator of hematopoiesis, underlies an immunodeficiency associated with myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Whereas an inversion relocalizes another GATA2 cis-element (−77) to the proto-oncogene EVI1, inducing EVI1 expression and AML, whether this reflects ectopic or physiological activity is unknown. We describe a mouse strain that decouples −77 function from proto-oncogene deregulation. The −77−/− mice exhibited a novel phenotypic constellation including late embryonic lethality and anemia. The −77 established a vital sector of the myeloid progenitor transcriptome, conferring multipotentiality. Unlike the +9.5−/− embryos, hematopoietic stem cell genesis was unaffected in −77−/− embryos. These results illustrate a paradigm in which cis-elements in a locus differentially control stem and progenitor cell transitions, and therefore the individual cis-element alterations cause unique and overlapping disease phenotypes. PMID:26601269

  19. Role of osteoclasts in regulating hematopoietic stem and progenitor cells

    PubMed Central

    Miyamoto, Takeshi

    2013-01-01

    Bone marrow (BM) cavities are utilized for hematopoiesis and to maintain hematopoietic stem cells (HSCs). HSCs have the ability to self-renew as well as to differentiate into multiple different hematopoietic lineage cells. HSCs produce their daughter cells throughout the lifespan of individuals and thus, maintaining HSCs is crucial for individual life. BM cavities provide a specialized microenvironment termed “niche” to support HSCs. Niches are composed of various types of cells such as osteoblasts, endothelial cells and reticular cells. Osteoclasts are unique cells which resorb bones and are required for BM cavity formation. Loss of osteoclast function or differentiation results in inhibition of BM cavity formation, an osteopetrotic phenotype. Osteoclasts are also reportedly required for hematopoietic stem and progenitor cell (HSPC) mobilization to the periphery from BM cavities. Thus, lack of osteoclasts likely results in inhibition of HSC maintenance and HSPC mobilization. However, we found that osteoclasts are dispensable for hematopoietic stem cell maintenance and mobilization by using three independent osteoclast-less animal models. In this review, I will discuss the roles of osteoclasts in hematopoietic stem cell maintenance and mobilization. PMID:24147255

  20. CXCR4 and Gab1 cooperate to control the development of migrating muscle progenitor cells

    PubMed Central

    Vasyutina, Elena; Stebler, Jürg; Brand-Saberi, Beate; Schulz, Stefan; Raz, Erez; Birchmeier, Carmen

    2005-01-01

    Long-range migrating progenitor cells generate hypaxial muscle, for instance the muscle of the limbs, hypoglossal cord, and diaphragm. We show here that migrating muscle progenitors express the chemokine receptor CXCR4. The corresponding ligand, SDF1, is expressed in limb and branchial arch mesenchyme; i.e., along the routes and at the targets of the migratory cells. Ectopic application of SDF1 in the chick limb attracts muscle progenitor cells. In CXCR4 mutant mice, the number of muscle progenitors that colonize the anlage of the tongue and the dorsal limb was reduced. Changes in the distribution of the muscle progenitor cells were accompanied by increased apoptosis, indicating that CXCR4 signals provide not only attractive cues but also control survival. Gab1 encodes an adaptor protein that transduces signals elicited by tyrosine kinase receptors, for instance the c-Met receptor, and plays a role in the migration of muscle progenitor cells. We found that CXCR4 and Gab1 interact genetically. For instance, muscle progenitors do not reach the anlage of the tongue in CXCR4;Gab1 double mutants; this target is colonized in either of the single mutants. Our analysis reveals a role of SDF1/CXCR4 signaling in the development of migrating muscle progenitors and shows that a threshold number of progenitor cells is required to generate muscle of appropriate size. PMID:16166380

  1. CXCR4 and Gab1 cooperate to control the development of migrating muscle progenitor cells.

    PubMed

    Vasyutina, Elena; Stebler, Jürg; Brand-Saberi, Beate; Schulz, Stefan; Raz, Erez; Birchmeier, Carmen

    2005-09-15

    Long-range migrating progenitor cells generate hypaxial muscle, for instance the muscle of the limbs, hypoglossal cord, and diaphragm. We show here that migrating muscle progenitors express the chemokine receptor CXCR4. The corresponding ligand, SDF1, is expressed in limb and branchial arch mesenchyme; i.e., along the routes and at the targets of the migratory cells. Ectopic application of SDF1 in the chick limb attracts muscle progenitor cells. In CXCR4 mutant mice, the number of muscle progenitors that colonize the anlage of the tongue and the dorsal limb was reduced. Changes in the distribution of the muscle progenitor cells were accompanied by increased apoptosis, indicating that CXCR4 signals provide not only attractive cues but also control survival. Gab1 encodes an adaptor protein that transduces signals elicited by tyrosine kinase receptors, for instance the c-Met receptor, and plays a role in the migration of muscle progenitor cells. We found that CXCR4 and Gab1 interact genetically. For instance, muscle progenitors do not reach the anlage of the tongue in CXCR4;Gab1 double mutants; this target is colonized in either of the single mutants. Our analysis reveals a role of SDF1/CXCR4 signaling in the development of migrating muscle progenitors and shows that a threshold number of progenitor cells is required to generate muscle of appropriate size. PMID:16166380

  2. Antidepressants increase neural progenitor cells in the human hippocampus

    PubMed Central

    Boldrini, Maura; Underwood, Mark D.; Hen, René; Rosoklija, Gorazd B.; Dwork, Andrew J.; Mann, J. John; Arango, Victoria

    2009-01-01

    Selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) increase neurogenesis in the dentate gyrus (DG) of rodents and nonhuman primates. We determined whether SSRIs or TCAs increase neural progenitor (NPCs) and dividing cells in the human DG in major depressive disorder (MDD). Whole frozen hippocampi from untreated subjects with MDD (N = 5), antidepressant-treated MDD (MDDT, N = 7), and controls (C, N = 7) were fixed, sectioned and immunostained for NPCs and dividing cell markers (nestin and Ki-67 respectively), NeuN and GFAP, in single and double labeling. NPC and dividing cell numbers in the DG were estimated by stereology. Clinical data were obtained by psychological autopsy and toxicological and neuropathological examination performed in all subjects. NPCs decreased with age (p = 0.034). Females had more NPCs than males (p = 0.023). Correcting for age and sex, MDDT receiving SSRIs had more NPCs than untreated MDD (p ≤ 0.001) and controls (p ≤ 0.001), NPCs were not different in SSRIs- and TCAs-treated MDDT (p = 0.169). Dividing cell number, unaffected by age or sex, was greater in MDDT receiving TCAs than in untreated MDD (p ≤ 0.001), SSRI-treated MDD (p = 0.001) and controls (p ≤ 0.001). The NPCs and dividing cells increase in MDDT was localized to the rostral DG. MDDT had a larger DG volume compared with untreated MDD or controls (p = 0.009). Antidepressants increase neural progenitor cell number in the anterior human dentate gyrus. Whether this finding is critical or necessary for the antidepressants effect remains to be determined. PMID:19606083

  3. Role of Pin1 in UVA-induced cell proliferation and malignant transformation in epidermal cells

    SciTech Connect

    Han, Chang Yeob; Hien, Tran Thi; Lim, Sung Chul; Kang, Keon Wook

    2011-06-24

    Highlights: {yields} Pin1 expression is enhanced by low energy UVA irradiation in both skin tissues of hairless mice and JB6 C141 epidermal cells. {yields} UVA irradiation increases activator protein-1 activity and cyclin D1 in a Pin1-dependent manner. {yields} UVA potentiates EGF-inducible, anchorage-independent growth of epidermal cells, and this is suppressed by Pin1 inhibition or by anti-oxidant. -- Abstract: Ultraviolet A (UVA) radiation ({lambda} = 320-400 nm) is considered a major cause of human skin cancer. Pin1, a peptidyl prolyl isomerase, is overexpressed in most types of cancer tissues and plays an important role in cell proliferation and transformation. Here, we demonstrated that Pin1 expression was enhanced by low energy UVA (300-900 mJ/cm{sup 2}) irradiation in both skin tissues of hairless mice and JB6 C141 epidermal cells. Exposure of epidermal cells to UVA radiation increased cell proliferation and cyclin D1 expression, and these changes were blocked by Pin1 inhibition. UVA irradiation also increased activator protein-1 (AP-1) minimal reporter activity and nuclear levels of c-Jun, but not c-Fos, in a Pin1-dependent manner. The increases in Pin1 expression and in AP-1 reporter activity in response to UVA were abolished by N-acetylcysteine (NAC) treatment. Finally, we found that pre-exposure of JB6 C141 cells to UVA potentiated EGF-inducible, anchorage-independent growth, and this effect was significantly suppressed by Pin1inhibition or by NAC.

  4. Smooth muscle progenitor cells from peripheral blood promote the neovascularization of endothelial colony-forming cells

    SciTech Connect

    Joo, Hyung Joon; Seo, Ha-Rim; Jeong, Hyo Eun; Choi, Seung-Cheol; Park, Jae Hyung; Yu, Cheol Woong; Hong, Soon Jun; Chung, Seok; Lim, Do-Sun

    2014-07-11

    Highlights: • Two distinct vascular progenitor cells are induced from adult peripheral blood. • ECFCs induce vascular structures in vitro and in vivo. • SMPCs augment the in vitro and in vivo angiogenic potential of ECFCs. • Both cell types have synergistic therapeutic potential in ischemic hindlimb model. - Abstract: Proangiogenic cell therapy using autologous progenitors is a promising strategy for treating ischemic disease. Considering that neovascularization is a harmonized cellular process that involves both endothelial cells and vascular smooth muscle cells, peripheral blood-originating endothelial colony-forming cells (ECFCs) and smooth muscle progenitor cells (SMPCs), which are similar to mature endothelial cells and vascular smooth muscle cells, could be attractive cellular candidates to achieve therapeutic neovascularization. We successfully induced populations of two different vascular progenitor cells (ECFCs and SMPCs) from adult peripheral blood. Both progenitor cell types expressed endothelial-specific or smooth muscle-specific genes and markers, respectively. In a protein array focused on angiogenic cytokines, SMPCs demonstrated significantly higher expression of bFGF, EGF, TIMP2, ENA78, and TIMP1 compared to ECFCs. Conditioned medium from SMPCs and co-culture with SMPCs revealed that SMPCs promoted cell proliferation, migration, and the in vitro angiogenesis of ECFCs. Finally, co-transplantation of ECFCs and SMPCs induced robust in vivo neovascularization, as well as improved blood perfusion and tissue repair, in a mouse ischemic hindlimb model. Taken together, we have provided the first evidence of a cell therapy strategy for therapeutic neovascularization using two different types of autologous progenitors (ECFCs and SMPCs) derived from adult peripheral blood.

  5. Mechanosensory calcium-selective cation channels in epidermal cells

    NASA Technical Reports Server (NTRS)

    Ding, J. P.; Pickard, B. G.

    1993-01-01

    This paper explores the properties and likely functions of an epidermal Ca(2+)-selective cation channel complex activated by tension. As many as eight or nine linked or linkable equivalent conductance units or co-channels can open together. Open time for co-channel quadruplets and quintuplets tends to be relatively long with millimolar Mg2+ (but not millimolar Ca2+) at the cytosolic face of excised plasma membrane. Sensitivity to tension is regulated by transmembrane voltage and temperature. Under some circumstances channel activity is sychronized in rhythmic pulses. Certain lanthanides and a cytoskeleton-disturbing herbicide that inhibit gravitropic reception act on the channel system at low concentrations. Specifically, ethyl-N-phenylcarbamate promotes tension-dependent activity at micromolar levels. With moderate suction, Gd3+ provided at about 0.5 micromole at the extracellular face of the membrane promotes for several seconds but may then become inhibitory. Provision at 1-2 micromoles promotes and subsequently inhibits more vigorously (often abruptly and totally), and at high levels inhibits immediately. La3+, a poor gravitropic inhibitor, acts similarly but much more gradually and only at much higher concentrations. These properties, particularly these susceptibilities to modulation, indicate that in vivo the mechanosensitive channel must be mechanosensory and mechanoregulatory. It could serve to transduce the shear forces generated in the integrated wall-membrane-cytoskeleton system during turgor changes and cell expansion as well as transducing the stresses induced by gravity, touch and flexure. In so far as such transduction is modulated by voltage and temperature, the channels would also be sensors for these modalities as long as the wall-membrane-cytoskeleton system experiences mechanical stress.

  6. Endothelial Progenitor Cells in Sprouting Angiogenesis: Proteases Pave the Way.

    PubMed

    Laurenzana, A; Fibbi, G; Margheri, F; Biagioni, A; Luciani, C; Del Rosso, M; Chillà, A

    2015-01-01

    Sprouting angiogenesis consists of the expansion and remodelling of existing vessels, where the vascular sprouts connect each other to form new vascular loops. Endothelial Progenitor Cells (EPCs) are a subtype of stem cells, with high proliferative potential, able to differentiate into mature Endothelial Cells (ECs) during the neovascularization process. In addition to this direct structural role EPCs improve neovascularization, also secreting numerous pro-angiogenic factors able to enhance the proliferation, survival and function of mature ECs, and other surrounding progenitor cells. While sprouting angiogenesis by mature ECs involves resident ECs, the vasculogenic contribution of EPCs is a high hurdle race. Bone marrowmobilized EPCs have to detach from the stem cell niche, intravasate into bone marrow vessels, reach the hypoxic area or tumour site, extravasate and incorporate into the new vessel lumen, thus complementing the resident mature ECs in sprouting angiogenesis. The goal of this review is to highlight the role of the main protease systems able to control each of these steps. The pivotal protease systems here described, involved in vascular patterning in sprouting angiogenesis, are the matrix-metalloproteinases (MMPs), the serineproteinases urokinase-type plasminogen activator (uPA) associated with its receptor (uPAR) and receptorassociated plasminogen/plasmin, the neutrophil elastase and the cathepsins. Since angiogenesis plays a critical role not only in physiological but also in pathological processes, such as in tumours, controlling the contribution of EPCs to the angiogenic process, through the regulation of the protease systems involved, could yield new opportunities for the therapeutic prospect of efficient control of pathological angiogenesis. PMID:26321757

  7. TLR2 Activation Inhibits Embryonic Neural Progenitor Cell Proliferation

    PubMed Central

    Okun, Eitan; Griffioen, Kathleen J.; Gen-Son, Tae; Lee, Jong-Hwan; Roberts, Nicholas J.; Mughal, Mohamed R.; Hutchison, Emmette; Cheng, Aiwu; Arumugam, Thiruma V.; Lathia, Justin D.; van Praag, Henriette; Mattson, Mark P.

    2010-01-01

    Toll-like receptors (TLRs) play essential roles in innate immunity, and increasing evidence indicates that these receptors are expressed in neurons, astrocytes and microglia in the brain, where they mediate responses to infection, stress and injury. To address the possibility that TLR2 heterodimer activation could affect progenitor cells in the developing brain, we analyzed the expression of TLR2 throughout the mouse cortical development, and assessed the role of TLR2 heterodimer activation in neural progenitor cell (NPC) proliferation. TLR2 mRNA and protein was expressed in the cortex in embryonic and early postnatal stages of development, and in cultured cortical NPC. While NPC from TLR2-deficient and wild type embryos had the same proliferative capacity, TLR2 activation by the synthetic bacterial lipopeptides Pam3CSK4 and FSL1, or low molecular weight hyaluronan, an endogenous ligand for TLR2, inhibited neurosphere formation in vitro. Intracerebral in utero administration of TLR2 ligands resulted in ventricular dysgenesis characterized by increased ventricle size, reduced proliferative area around the ventricles, increased cell density, an increase in PH3+ cells and a decrease in BrdU+ cells in the sub-ventricular zone. Our findings indicate that loss of TLR2 does not result in defects in cerebral development. However, TLR2 is expressed and functional in the developing telencephalon from early embryonic stages and infectious agent-related activation of TLR2 inhibits NPC proliferation. TLR2–mediated inhibition of NPC proliferation may therefore be a mechanism by which infection, ischemia and inflammation adversely affect brain development. PMID:20456021

  8. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    PubMed Central

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes. PMID:27212953

  9. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins.

    PubMed

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes. PMID:27212953

  10. Effects of physical activity on endothelial progenitor cells (EPCs)

    PubMed Central

    De Biase, Chiara; De Rosa, Roberta; Luciano, Rossella; De Luca, Stefania; Capuano, Ernesto; Trimarco, Bruno; Galasso, Gennaro

    2014-01-01

    Physical activity has a therapeutic role in cardiovascular disease (CVD), through its beneficial effects on endothelial function and cardiovascular system. Circulating endothelial progenitor cells (EPCs) are bone marrow (BM) derived cells that represent a novel therapeutic target in CVD patients, because of their ability to home to sites of ischemic injury and repair the damaged vessels. Several studies show that physical activity results in a significant increase in circulating EPCs, and, in particular, there are some evidence of the beneficial exercise-induced effects on EPCs activity in CVD settings, including coronary artery disease (CAD), heart failure (HF), and peripheral artery disease (PAD). The aim of this paper is to review the current evidence about the beneficial effects of physical exercise on endothelial function and EPCs levels and activity in both healthy subjects and patients with CVD. PMID:24550833

  11. c-Rel in Epidermal Homeostasis: A Spotlight on c-Rel in Cell Cycle Regulation.

    PubMed

    Lorenz, Verena N; Schön, Michael P; Seitz, Cornelia S

    2016-06-01

    To maintain proper skin barrier function, epidermal homeostasis requires a subtly governed balance of proliferating and differentiating keratinocytes. While differentiation takes place in the suprabasal layers, proliferation, including mitosis, is usually restricted to the basal layer. Only recently identified as an important regulator of epidermal homeostasis, c-Rel, an NF-κB transcription factor subunit, affects the viability and proliferation of epidermal keratinocytes. In human keratinocytes, decreased expression of c-Rel causes a plethora of dysregulated cellular functions including impaired cell viability, increased apoptosis, and abnormalities during mitosis and cell cycle regulation. On the other hand, c-Rel shows aberrant expression in many epidermal tumors. Here, in the context of its role in different cell types and compared with other NF-κB subunits, we discuss the putative function of c-Rel as a regulator of epidermal homeostasis and mitotic progression. In addition, implications for disease pathophysiology with perturbed c-Rel function and abnormal homeostasis, such as epidermal carcinogenesis, will be discussed. PMID:27032306

  12. Human neural progenitor cells generated from induced pluripotent stem cells can survive, migrate, and integrate in the rodent spinal cord

    PubMed Central

    Sareen, Dhruv; Gowing, Geneviève; Sahabian, Anais; Staggenborg, Kevin; Paradis, Renée; Avalos, Pablo; Latter, Jessica; Ornelas, Loren; Garcia, Leslie; Svendsen, Clive N.

    2014-01-01

    Transplantation of human neural progenitor cells (NPCs) into the brain or spinal cord to replace lost cells, modulate the injury environment or create a permissive milieu to protect and regenerate host neurons is a promising therapeutic strategy for neurological diseases. Deriving NPCs from human fetal tissue is feasible, though problematic issues include limited sources and ethical concerns. Here we describe a new and abundant source of NPCs derived from human induced pluripotent stem cells (iPSCs). A novel chopping technique was used to transform adherent iPSCs into free-floating spheres that were easy to maintain and were expandable (EZ spheres) (Ebert et al., 2013). These EZ spheres could be differentiated towards NPC spheres with a spinal cord phenotype using a combination of all-trans retinoic acid (ATRA) and epidermal growth factor (EGF) and fibroblast growth factor-2 (FGF-2) mitogens. Suspension cultures of NPCs derived from human iPSCs or fetal tissue have similar characteristics, though they were not similar when grown as adherent cells. In addition, iPSC-derived NPCs (iNPCs) survived grafting into the spinal cord of athymic nude rats with no signs of overgrowth and with a very similar profile to human fetal-derived NPCs (fNPCs). These results suggest that human iNPCs behave like fNPCs and could thus be a valuable alternative for cellular regenerative therapies of neurological diseases. PMID:24610630

  13. Osteopontin Neutralization Abrogates the Liver Progenitor Cell Response and Fibrogenesis in Mice

    PubMed Central

    Coombes, J; Swiderska-Syn, M; Dollé, L; Reid, D; Eksteen, B; Claridge, L; Briones-Orta, MA; Shetty, S; Oo, YH; Riva, A; Chokshi, S; Papa, S; Mi, Z; Kuo, PC; Williams, R; Canbay, A; Adams, DH; Diehl, AM; van Grunsven, LA; Choi, SS; Syn, WK

    2015-01-01

    Background Chronic liver injury triggers a progenitor-cell repair-response, and liver fibrosis occurs when repair becomes de-regulated. Previously, we reported that reactivation of the Hedgehog (Hh) pathway promotes fibrogenic liver-repair. Osteopontin (OPN) is a Hh-target, and a cytokine that is highly upregulated in fibrotic tissues, and regulates stem-cell fate. Thus, we hypothesized that OPN may modulate liver progenitor-cell response, and thereby, modulate fibrotic outcomes. We further evaluated the impact of OPN-neutralization on murine liver fibrosis. Methods Liver progenitors (603B and BMOL) were treated with OPN-neutralizing aptamers in the presence or absence of TGF–β, to determine if (and how) OPN modulates liver progenitor function. Effects of OPN-neutralization (using OPN-aptamers or OPN-neutralizing antibodies) on liver progenitor-cell response and fibrogenesis were assessed in three models of liver fibrosis (carbon tetrachloride, methionine-choline deficient diet, 3, 5,-diethoxycarbonyl-1,4-dihydrocollidine diet) by qRTPCR, Sirius-Red staining, hydroxyproline assay, and semi-quantitative double-immunohistochemistry. Finally, OPN expression and liver progenitor response were corroborated in liver tissues obtained from patients with chronic liver disease. Results OPN is over-expressed by liver progenitors in humans and mice. In cultured progenitors, OPN enhances viability and wound-healing by modulating TGF-β signaling. In vivo, OPN-neutralization attenuates the liver progenitor-cell response, reverses epithelial-mesenchymal-transition in Sox9+ cells, and abrogates liver fibrogenesis. Conclusions OPN upregulation during liver injury is a conserved repair-response, and influences liver progenitor-cell function. OPN-neutralization abrogates the liver progenitor-cell response and fibrogenesis in mouse models of liver fibrosis. PMID:24902765

  14. Circulating endothelial cells and their progenitors in acute myeloid leukemia

    PubMed Central

    Zahran, Asmaa Mohammed; Aly, Sanaa Shaker; Altayeb, Hanan Ahmed; Ali, Arwa Mohammed

    2016-01-01

    Acute myeloid leukemia (AML) is an aggressive hematological malignancy characterized by the accumulation of immature myeloid progenitor cells in the bone marrow. Studies are required to investigate the prognostic and predictive value of surrogate biomarkers. Given the importance of angiogenesis in oncology in terms of pathogenesis as well as being a target for treatment, circulating endothelial cells (CECs) and endothelial progenitor cells (EPCs) are promising candidates to serve as such markers. The aim of the present study was to quantify CECs and EPCs in patients with AML at initial diagnosis and following induction chemotherapy, and to correlate these findings with the response to treatment in AML patients. The present study included 40 patients with de novo AML and 20 age- and gender-matched healthy controls. CECs and EPCs were evaluated by flow cytometry at initial diagnosis and after induction chemotherapy (3+7 protocol for AML other than M3 and all-trans-retinoic acid plus anthracycline for M3 disease). CECs and EPCs were significantly higher in AML patients at diagnosis and after induction chemotherapy than in controls. After induction chemotherapy, CECs and EPCs were significantly decreased compared with the levels at initial diagnosis. Patients who achieved complete response (n=28) had lower initial CEC and EPC levels compared with patients who did not respond to treatment. These results suggest that CEC levels are higher in AML patients and may correlate with disease status and treatment response. Further investigations are required to better determine the predictive value and implication of these cells in AML management. PMID:27602121

  15. CD133 positive progenitor endothelial cell lines from human cord blood.

    PubMed

    Paprocka, Maria; Krawczenko, Agnieszka; Dus, Danuta; Kantor, Aneta; Carreau, Aude; Grillon, Catherine; Kieda, Claudine

    2011-08-01

    Endothelial progenitor cells (EPCs) modulate postnatal vascularization and contribute to vessel regeneration in adults. Stem cells and progenitor cells were found in umbilical cord blood, bone marrow, and mobilized peripheral blood cells, from where they were isolated and cultured. However, the yield of progenitor cells is usually not sufficient for clinical application and the quality of progenitor cells varies. The aim of the study was the immortalization of early progenitor cells with high proliferative potential, capable to differentiate to EPCs and, further, toward endothelial cells. Two cell lines, namely HEPC-CB.1 and HEPC-CB.2 (human endothelial progenitor cells-cord blood) were isolated. As assessed by specific antibody labeling and flow cytometric analysis, they express a panel of stem cell markers: CD133, CD13, CD271, CD90 and also endothelial cell markers: CD202b, CD309 (VEGFR2), CD146, CD105, and CD143 but they do not present markers of finally differentiated endothelial cells: CD31, vWf, nor CD45 which is a specific hematopoietic cell marker. Using the multiplex Cytometric Bead Assay, the simultaneous production of proangiogenic cytokines IL8, angiogenin, and VEGF was demonstrated in normoxia and was shown to be increased by hypoxia. Both cell lines, similarly as mature endothelial cells, underwent in vitro pre-angiogenic process, formed pseudovessel structures and present an accelerated angiogenesis in hypoxic conditions. To date, these are the first CD133 positive established cell lines from human cord blood cells. PMID:21710642

  16. Epidermal Th22 and Tc17 cells form a localized disease memory in clinically healed psoriasis.

    PubMed

    Cheuk, Stanley; Wikén, Maria; Blomqvist, Lennart; Nylén, Susanne; Talme, Toomas; Ståhle, Mona; Eidsmo, Liv

    2014-04-01

    Psoriasis is a common and chronic inflammatory skin disease in which T cells play a key role. Effective treatment heals the skin without scarring, but typically psoriasis recurs in previously affected areas. A pathogenic memory within the skin has been proposed, but the nature of such site-specific disease memory is unknown. Tissue-resident memory T (TRM) cells have been ascribed a role in immunity after resolved viral skin infections. Because of their localization in the epidermal compartment of the skin, TRM may contribute to tissue pathology during psoriasis. In this study, we investigated whether resolved psoriasis lesions contain TRM cells with the ability to maintain and potentially drive recurrent disease. Three common and effective therapies, narrowband-UVB treatment and long-term biologic treatment systemically inhibiting TNF-α or IL-12/23 signaling were studied. Epidermal T cells were highly activated in psoriasis and a high proportion of CD8 T cells expressed TRM markers. In resolved psoriasis, a population of cutaneous lymphocyte-associated Ag, CCR6, CD103, and IL-23R expressing epidermal CD8 T cells was highly enriched. Epidermal CD8 T cells expressing the TRM marker CD103 responded to ex vivo stimulation with IL-17A production and epidermal CD4 T cells responded with IL-22 production after as long as 6 y of TNF-α inhibition. Our data suggest that epidermal TRM cells are retained in resolved psoriasis and that these cells are capable of producing cytokines with a critical role in psoriasis pathogenesis. We provide a potential mechanism for a site-specific T cell-driven disease memory in psoriasis. PMID:24610014

  17. Autologous Stem Cell Therapy: How Aging and Chronic Diseases Affect Stem and Progenitor Cells

    PubMed Central

    Efimenko, Anastasia Yu.; Kochegura, Tatiana N.; Akopyan, Zhanna A.; Parfyonova, Yelena V.

    2015-01-01

    Abstract During recent years different types of adult stem/progenitor cells have been successfully applied for the treatment of many pathologies, including cardiovascular diseases. The regenerative potential of these cells is considered to be due to their high proliferation and differentiation capacities, paracrine activity, and immunologic privilege. However, therapeutic efficacy of the autologous stem/progenitor cells for most clinical applications remains modest, possibly because of the attenuation of their regenerative potential in aged patients with chronic diseases such as cardiovascular diseases and metabolic disorders. In this review we will discuss the risk factors affecting the therapeutic potential of adult stem/progenitor cells as well as the main approaches to mitigating them using the methods of regenerative medicine. PMID:26309780

  18. Nitrative Stress Participates in Endothelial Progenitor Cell Injury in Hyperhomocysteinemia

    PubMed Central

    Dong, Yu; Sun, Qi; Liu, Teng; Wang, Huanyuan; Jiao, Kun; Xu, Jiahui; Liu, Xin; Liu, Huirong; Wang, Wen

    2016-01-01

    In order to investigate the role of nitrative stress in vascular endothelial injury in hyperhomocysteinemia (HHcy), thirty healthy adult female Wistar rats were randomly divided into three groups: control, hyperhomocysteinemia model, and hyperhomocysteinemia with FeTMPyP (peroxynitrite scavenger) treatment. The endothelium-dependent dilatation of thoracic aorta in vitro was determined by response to acetylcholine (ACh). The histological changes in endothelium were assessed by HE staining and scanning electron microscopy (SEM). The expression of 3-nitrotyrosine (NT) in thoracic aorta was demonstrated by immunohistochemistry and immunofluorescence, and the number of circulating endothelial progenitor cells (EPCs) was quantified by flow cytometry. Hyperhomocysteinemia caused significant endothelial injury and dysfunction including vasodilative and histologic changes, associated with higher expression of NT in thoracic aorta. FeTMPyP treatment reversed these injuries significantly. Further, the effect of nitrative stress on cultured EPCs in vitro was investigated by administering peroxynitrite donor (3-morpholino-sydnonimine, SIN-1) and peroxynitrite scavenger (FeTMPyP). The roles of nitrative stress on cell viability, necrosis and apoptosis were evaluated with 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium (MTT) assay, lactate dehydrogenase (LDH) release assay and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, respectively. Also, the phospho-eNOS expression and tube formation in Matrigel of cultured EPCs was detected. Our data showed that the survival of EPCs was much lower in SIN-1 group than in vehicle group, both the apoptosis and necrosis of EPCs were much more severe, and the p-eNOS expression and tube formation in Matrigel were obviously declined. Subsequent pretreatment with FeTMPyP reversed these changes. Further, pretreatment with FeTMPyP reversed homocysteine-induced EPC injury. In conclusion, this study indicates that

  19. Nitrative Stress Participates in Endothelial Progenitor Cell Injury in Hyperhomocysteinemia.

    PubMed

    Dong, Yu; Sun, Qi; Liu, Teng; Wang, Huanyuan; Jiao, Kun; Xu, Jiahui; Liu, Xin; Liu, Huirong; Wang, Wen

    2016-01-01

    In order to investigate the role of nitrative stress in vascular endothelial injury in hyperhomocysteinemia (HHcy), thirty healthy adult female Wistar rats were randomly divided into three groups: control, hyperhomocysteinemia model, and hyperhomocysteinemia with FeTMPyP (peroxynitrite scavenger) treatment. The endothelium-dependent dilatation of thoracic aorta in vitro was determined by response to acetylcholine (ACh). The histological changes in endothelium were assessed by HE staining and scanning electron microscopy (SEM). The expression of 3-nitrotyrosine (NT) in thoracic aorta was demonstrated by immunohistochemistry and immunofluorescence, and the number of circulating endothelial progenitor cells (EPCs) was quantified by flow cytometry. Hyperhomocysteinemia caused significant endothelial injury and dysfunction including vasodilative and histologic changes, associated with higher expression of NT in thoracic aorta. FeTMPyP treatment reversed these injuries significantly. Further, the effect of nitrative stress on cultured EPCs in vitro was investigated by administering peroxynitrite donor (3-morpholino-sydnonimine, SIN-1) and peroxynitrite scavenger (FeTMPyP). The roles of nitrative stress on cell viability, necrosis and apoptosis were evaluated with 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium (MTT) assay, lactate dehydrogenase (LDH) release assay and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, respectively. Also, the phospho-eNOS expression and tube formation in Matrigel of cultured EPCs was detected. Our data showed that the survival of EPCs was much lower in SIN-1 group than in vehicle group, both the apoptosis and necrosis of EPCs were much more severe, and the p-eNOS expression and tube formation in Matrigel were obviously declined. Subsequent pretreatment with FeTMPyP reversed these changes. Further, pretreatment with FeTMPyP reversed homocysteine-induced EPC injury. In conclusion, this study indicates that

  20. Alcohol Disrupts Human Liver Stem/Progenitor Cell Proliferation and Differentiation

    PubMed Central

    Shi, Xin; Chang, Chia-Cheng; Basson, Marc D; Upham, Brad L; Wei, Lixin; Zhang, Ping

    2016-01-01

    Objective Excessive alcohol consumption injures the liver resulting in various liver diseases including liver cirrhosis. Advanced liver disease continues to be a major challenge to human health. Liver stem/progenitor cells (LSPCs) are tissue specific precursors with a distinct capacity of multi-lineage differentiation. These precursor cells may play an important role in the process of tissue injury repair and pathological transition of liver structures. At the present time, knowledge about the effect of alcohol on LSPC function during the development of alcoholic liver disease remains absent. This study was conducted to investigate changes in LSPC activity of proliferation and differentiation following alcohol exposure. The disruption of cell signaling mechanisms underlying alcohol-induced alteration of LSPC activities was also examined. Methods Primary and immortalized human liver stem cells (HL1-1 cells and HL1-hT1 cells, respectively) were cultured in media optimized for cell proliferation and hepatocyte differentiation in the absence and presence of ethanol. Changes in cell morphology, proliferation and differentiation were determined. Functional disruption of cell signaling components following alcohol exposure was examined. Results Ethanol exposure suppressed HL1-1 cell growth [as measured by cell 5-bromo-2-deoxyuridine (BrdU) incorporation] mediated by epidermal growth factor (EGF) or EGF plus interleukin-6 (IL-6) in an ethanol dose-dependent manner. Similarly, ethanol inhibited BrdU incorporation into HL1-hT1 cells. Cyclin D1 mRNA expression by HL1-hT1 cells was suppressed when cells were cultured with 50 and 100 mM ethanol. Ethanol exposure induced morphological change of HL1-1 cells toward a myofibroblast-like phenotype. Furthermore, ethanol down-regulated E-cadherin expression while increasing collagen I expression by HL1-1 cells. Ethanol also stimulated Snail transcriptional repressor (Snail) and α-smooth muscle actin (α-SMA) gene expression by HL1

  1. Proteomic Cornerstones of Hematopoietic Stem Cell Differentiation: Distinct Signatures of Multipotent Progenitors and Myeloid Committed Cells*

    PubMed Central

    Klimmeck, Daniel; Hansson, Jenny; Raffel, Simon; Vakhrushev, Sergey Y.; Trumpp, Andreas; Krijgsveld, Jeroen

    2012-01-01

    Regenerative tissues such as the skin epidermis, the intestinal mucosa or the hematopoietic system are organized in a hierarchical manner with stem cells building the top of this hierarchy. Somatic stem cells harbor the highest self-renewal activity and generate a series of multipotent progenitors which differentiate into lineage committed progenitors and subsequently mature cells. In this report, we applied an in-depth quantitative proteomic approach to analyze and compare the full proteomes of ex vivo isolated and FACS-sorted populations highly enriched for either multipotent hematopoietic stem/progenitor cells (HSPCs, LinnegSca-1+c-Kit+) or myeloid committed precursors (LinnegSca-1−c-Kit+). By employing stable isotope dimethyl labeling and high-resolution mass spectrometry, more than 5000 proteins were quantified. From biological triplicate experiments subjected to rigorous statistical evaluation, 893 proteins were found differentially expressed between multipotent and myeloid committed cells. The differential protein content in these cell populations points to a distinct structural organization of the cytoskeleton including remodeling activity. In addition, we found a marked difference in the expression of metabolic enzymes, including a clear shift of specific protein isoforms of the glycolytic pathway. Proteins involved in translation showed a collective higher expression in myeloid progenitors, indicating an increased translational activity. Strikingly, the data uncover a unique signature related to immune defense mechanisms, centering on the RIG-I and type-1 interferon response systems, which are installed in multipotent progenitors but not evident in myeloid committed cells. This suggests that specific, and so far unrecognized, mechanisms protect these immature cells before they mature. In conclusion, this study indicates that the transition of hematopoietic stem/progenitors toward myeloid commitment is accompanied by a profound change in processing of

  2. Connective tissue progenitor cell growth characteristics on textured substrates.

    PubMed

    Mata, Alvaro; Boehm, Cynthia; Fleischman, Aaron J; Muschler, George F; Roy, Shuvo

    2007-01-01

    Growth characteristics of human connective tissue progenitor (CTP) cells were investigated on smooth and textured substrates, which were produced using MEMS (microelectromechanical systems) fabrication technology. Human bone marrow derived cells were cultured for 9 days under conditions promoting osteoblastic differentiation on polydimethylsiloxane (PDMS) substrates comprising smooth (non-patterned) surfaces (SMOOTH), 4 different cylindrical post micro-textures (POSTS) that were 7-10 microm high and 5, 10, 20, and 40 microm diameter, respectively, and channel micro-textures (CHANNELS) with curved cross-sections that were 11 microm high, 45 microm wide, and separated by 5 microm wide ridges. Standard glass-tissue culture surfaces were used as controls. Micro-textures resulted in the modification of CTP morphology, attachment, migration, and proliferation characteristics. Specifically, cells on POSTS exhibited more contoured morphology with closely packed cytoskeletal actin microfilaments compared to the more random orientation in cells grown on SMOOTH. CTP colonies on 10 gm-diameter POSTS exhibited higher cell number than any other POSTS, and a significant increase in cell number (442%) compared to colonies on SMOOTH (71%). On CHANNELS, colonies tended to be denser (229%) than on POSTS (up to 140% on 10 microm POSTS), and significantly more so compared to those on SMOOTH (104%). PMID:18019838

  3. Identification of Candidate Transcriptional Regulators of Epidermal Transfer Cell Development in Vicia faba Cotyledons.

    PubMed

    Arun-Chinnappa, Kiruba S; McCurdy, David W

    2016-01-01

    Transfer cells (TCs) are anatomically-specialized cells formed at apoplasmic-symplasmic bottlenecks in nutrient transport pathways in plants. TCs form invaginated wall ingrowths which provide a scaffold to amplify plasma membrane surface area and thus increase the density of nutrient transporters required to achieve enhanced nutrient flow across these bottlenecks. Despite their importance to nutrient transport in plants, little is known of the transcriptional regulation of wall ingrowth formation. Here, we used RNA-Seq to identify transcription factors putatively involved in regulating epidermal TC development in cotyledons of Vicia faba. Comparing cotyledons cultured for 0, 3, 9, and 24 h to induce trans-differentiation of epidermal TCs identified 43 transcription factors that showed either epidermal-specific or epidermal-enhanced expression, and 10 that showed epidermal-specific down regulation. Members of the WRKY and ethylene-responsive families were prominent in the cohort of transcription factors showing epidermal-specific or epidermal-enhanced expression, consistent with the initiation of TC development often representing a response to stress. Members of the MYB family were also prominent in these categories, including orthologs of MYB genes involved in localized secondary wall deposition in Arabidopsis thaliana. Among the group of transcription factors showing down regulation were various homeobox genes and members of the MADs-box and zinc-finger families of poorly defined functions. Collectively, this study identified several transcription factors showing expression characteristics and orthologous functions that indicate likely participation in transcriptional regulation of epidermal TC development in V. faba cotyledons. PMID:27252730

  4. Hair matrix germinative epidermal cells confer follicle-inducing capabilities on dermal sheath and high passage papilla cells.

    PubMed

    Reynolds, A J; Jahoda, C A

    1996-10-01

    Low passage cultured dermal papilla cells from adult rats stimulate complete hair follicle neogenesis when re-implanted into heterotypic skin. In contrast, cultured sheath cells are non-inductive despite sharing other behavioural characteristics (a common lineage and in situ proximity) with papilla cells. However, since sheath cells can behave inductively in amputated follicles after regenerating the papilla, this poses the question of what influences the sheath to papilla cell transition? During reciprocal tissue interactions specific epidermal cues are crucial to skin appendage development, and while in vivo assays to date have focussed on dermal interactive influence, our aim was to investigate epidermal potential. We have previously observed that hair follicle epidermal cells display exceptional interactive behaviour when combined with follicle dermal cells in vitro. Thus in the present study, hair follicle germinative, outer root sheath or skin basal epidermal cells were separately combined with each of three non-inductive dermal cell types (high passage papilla, low passage sheath or fibroblast) and then implanted into small ear skin wounds. The sheath/germinative and papilla/germinative cell implants repeatedly induced giant vibrissa-type follicles and fibres. In complete contrast, any single cell type and all other forms of recombination were consistently non-inductive. Hence, the adult germinative epidermal cells enable non-inductive adult dermal cells to stimulate hair follicle neogenesis, effectively, by altering their 'status', causing the sheath cells to 'specialise' and the 'aged' papilla cells to 'rejuvenate'. PMID:8898222

  5. Generation and In Vitro Expansion of Hepatic Progenitor Cells from Human iPS Cells.

    PubMed

    Yanagida, Ayaka; Nakauchi, Hiromitsu; Kamiya, Akihide

    2016-01-01

    Stem cells have the unique properties of self-renewal and multipotency (producing progeny belonging to two or more lineages). Induced pluripotent stem (iPS) cells can be generated from somatic cells by simultaneous expression of pluripotent factors (Oct3/4, Klf4, Sox2, and c-Myc). They share the same properties as embryonic stem (ES) cells and can differentiate into several tissue cells, i.e., neurons, hematopoietic cells, and liver cells. Therefore, iPS cells are suitable candidate cells for regenerative medicine and analyses of disease mechanisms.The liver is the major organ that regulates a multitude of metabolic functions. Hepatocytes are the major cell type populating the liver parenchyma and express several metabolic enzymes that are necessary for liver functions. Although hepatocytes are essential for maintaining homeostasis, it is difficult to alter artificial and transplanted cells because of their multifunctionality, donor shortage, and immunorejection risk. During liver development, hepatic progenitor cells in the fetal liver differentiate into both mature hepatocytes and cholangiocytes. As hepatic progenitor cells have bipotency and high proliferation ability, they could present a potential source for generating transplantable cells or as a liver study model. Here we describe the induction and purification of hepatic progenitor cells derived from human iPS cells. These cells can proliferate for a long term under suitable culture conditions. PMID:25697415

  6. Mast cells and basophils: trojan horses of conventional lin- stem/progenitor cell isolates.

    PubMed

    Heneberg, Petr

    2011-11-01

    Cancer microenvironment is increasingly recognized as an important factor affecting cancer onset and progression. Since Wirchow reported in 1863 that tumors contain inflammatory cells, the field shifted significantly forward, and immune cells residing in tumors appear to be attractive targets of cancer therapies. For some methods, such as stem/progenitor cell isolation from both cancer and healthy tissues, removal of contaminating immune cells is crucial to achieve consistent, reproducible and accurate results. Despite current methods of lineage negative selection accounts for removal of over 99 % of immune cells from stem/progenitor cell isolates, the vast majority of lineage antibody cocktails retain basophils, dendritic cells, and mast cells. Here we discuss the ability of the most commonly used lineage markers to bind to the plasma membrane of mast cells and/or basophils, and suggest alternatives, which may be used for negative selection of these cellular populations. Both, mast cells and basophils, were shown to participate actively in cancer-associated angiogenesis, tissue remodeling and recruitment of other immune cell types, including eosinophils, B cells, memory T cells and Treg cells. In turn, tumor-derived peptides and chemotactic factors are known to recruit and activate mast cells in neoplasias, resulting in altered tumor progression. Repeated findings of CD34+ populations of mast cells and basophils further highlight necessity of their separation from stem/progenitor cell isolates in both, preclinical experiments and clinical praxis. PMID:22103846

  7. Regenerative and reparative effects of human chorion-derived stem cell conditioned medium on photo-aged epidermal cells.

    PubMed

    Li, Qiankun; Chen, Yan; Ma, Kui; Zhao, Along; Zhang, Cuiping; Fu, Xiaobing

    2016-04-17

    Epidermal cells are an important regenerative source for skin wound healing. Aged epidermal cells have a low ability to renew themselves and repair skin injury. Ultraviolet (UV) radiation, particularly UVB, can cause photo-aging of the skin by suppressing the viability of human epidermal cells. A chorion-derived stem cell conditioned medium (CDSC-CNM) is thought to have regenerative properties. This study aimed to determine the regenerative effects of CDSC-CNM on UVB-induced photo-aged epidermal cells. Epidermal cells were passaged four times and irradiated with quantitative UVB, and non-irradiated cells served as a control group. Cells were then treated with different concentrations of CDSC-CNM. Compared to the non-irradiated group, the proliferation rates and migration rates of UVB-induced photo-aged epidermal cells significantly decreased (p < 0.05) with increasing intracellular radical oxygen species (ROS) generation and DNA damage. After treatment with CDSC-CNM, photo-aged epidermal cells significantly improved their viability, and their ROS generation and DNA damage decreased. The secretory factors in CDSC-CNM, including epidermal growth factor (EGF), transforming growth factor-β (TGF-β), interleukin (IL)-6, and IL-8 and the related signaling pathway protein levels, increased compared to the control medium (CM). The potential regenerative and reparative effects of CDSC-CNM indicate that it may be a candidate material for the treatment of prematurely aged skin. The functions of the secretory factors and the mechanisms of CDSC-CNM therapy deserve further attention. PMID:27097375

  8. Generation of an expandable intermediate mesoderm restricted progenitor cell line from human pluripotent stem cells.

    PubMed

    Kumar, Nathan; Richter, Jenna; Cutts, Josh; Bush, Kevin T; Trujillo, Cleber; Nigam, Sanjay K; Gaasterland, Terry; Brafman, David; Willert, Karl

    2015-01-01

    The field of tissue engineering entered a new era with the development of human pluripotent stem cells (hPSCs), which are capable of unlimited expansion whilst retaining the potential to differentiate into all mature cell populations. However, these cells harbor significant risks, including tumor formation upon transplantation. One way to mitigate this risk is to develop expandable progenitor cell populations with restricted differentiation potential. Here, we used a cellular microarray technology to identify a defined and optimized culture condition that supports the derivation and propagation of a cell population with mesodermal properties. This cell population, referred to as intermediate mesodermal progenitor (IMP) cells, is capable of unlimited expansion, lacks tumor formation potential, and, upon appropriate stimulation, readily acquires properties of a sub-population of kidney cells. Interestingly, IMP cells fail to differentiate into other mesodermally-derived tissues, including blood and heart, suggesting that these cells are restricted to an intermediate mesodermal fate. PMID:26554899

  9. Neonatal Heart-Enriched miR-708 Promotes Differentiation of Cardiac Progenitor Cells in Rats

    PubMed Central

    Deng, Shengqiong; Zhao, Qian; Zhou, Xianjin; Zhang, Lin; Bao, Luer; Zhen, Lixiao; Zhang, Yuzhen; Fan, Huimin; Liu, Zhongmin; Yu, Zuoren

    2016-01-01

    Cardiovascular disease is becoming the leading cause of death throughout the world. However, adult hearts have limited potential for regeneration after pathological injury, partly due to the quiescent status of stem/progenitor cells. Reactivation of cardiac stem/progenitor cells to create more myocyte progeny is one of the key steps in the regeneration of a damaged heart. In this study, miR-708 was identified to be enriched in the neonatal cardiomyocytes of rats, but this has not yet been proven in adult humans. A lower level of miR-708 in c-kit(+) stem/progenitor cells was detected compared to non-progenitors. Overexpression of miR-708 induced cardiomyocyte differentiation of cardiac stem/progenitor cells. This finding strengthened the potential of applying miRNAs in the regeneration of injured hearts, and this indicates that miR-708 could be a novel candidate for treatment of heart diseases. PMID:27338347

  10. Neonatal Heart-Enriched miR-708 Promotes Differentiation of Cardiac Progenitor Cells in Rats.

    PubMed

    Deng, Shengqiong; Zhao, Qian; Zhou, Xianjin; Zhang, Lin; Bao, Luer; Zhen, Lixiao; Zhang, Yuzhen; Fan, Huimin; Liu, Zhongmin; Yu, Zuoren

    2016-01-01

    Cardiovascular disease is becoming the leading cause of death throughout the world. However, adult hearts have limited potential for regeneration after pathological injury, partly due to the quiescent status of stem/progenitor cells. Reactivation of cardiac stem/progenitor cells to create more myocyte progeny is one of the key steps in the regeneration of a damaged heart. In this study, miR-708 was identified to be enriched in the neonatal cardiomyocytes of rats, but this has not yet been proven in adult humans. A lower level of miR-708 in c-kit(+) stem/progenitor cells was detected compared to non-progenitors. Overexpression of miR-708 induced cardiomyocyte differentiation of cardiac stem/progenitor cells. This finding strengthened the potential of applying miRNAs in the regeneration of injured hearts, and this indicates that miR-708 could be a novel candidate for treatment of heart diseases. PMID:27338347

  11. L-arginine is a radioprotector for hematopoietic progenitor cells.

    PubMed

    Pearce, Linda L; Zheng, Xichen; Martinez-Bosch, Sandra; Kerr, Patrick P; Khlangwiset, Pornsri; Epperly, Michael W; Fink, Mitchell P; Greenberger, Joel S; Peterson, Jim

    2012-06-01

    L-arginine is shown to protect hematopoietic progenitor (32D cl 3) cells from death due to exposure to γ radiation ((137)Cs). Some of the other intermediates in the urea cycle, namely ornithine and citrulline, plus urea itself, were not found to have any significant impact on cell survival after irradiation. Intriguingly, supplementation of irradiated cells with L-arginine results in decreased production of peroxynitrite, suggesting that suppression of superoxide generation by nitric oxide synthase in one or more microenvironments is an important factor in the observed radioprotection. The absence of any radioprotective effect of L-arginine in cells at 3% oxygen also confirms the involvement of one or more oxygen-derived species. Knockdown experiments with nitric oxide synthase (NOS) siRNAs in cells and NOS knockout animals confirm that the observed radioprotection is associated with nNOS (NOS-1). L-arginine also ameliorates the transient inhibition of the electron-transport chain complex I that occurs within 30 min of completing the dose (10 Gy) and that appears to be a functional marker for postirradiation mitochondrial oxidant production. PMID:22175298

  12. Transdifferentiation of human endothelial progenitors into smooth muscle cells.

    PubMed

    Ji, HaYeun; Atchison, Leigh; Chen, Zaozao; Chakraborty, Syandan; Jung, Youngmee; Truskey, George A; Christoforou, Nicolas; Leong, Kam W

    2016-04-01

    Access to smooth muscle cells (SMC) would create opportunities for tissue engineering, drug testing, and disease modeling. Herein we report the direct conversion of human endothelial progenitor cells (EPC) to induced smooth muscle cells (iSMC) by induced expression of MYOCD. The EPC undergo a cytoskeletal rearrangement resembling that of mesenchymal cells within 3 days post initiation of MYOCD expression. By day 7, the reprogrammed cells show upregulation of smooth muscle markers ACTA2, MYH11, and TAGLN by qRT-PCR and ACTA2 and MYH11 expression by immunofluorescence. By two weeks, they resemble umbilical artery SMC in microarray gene expression analysis. The iSMC, in contrast to EPC control, show calcium transients in response to phenylephrine stimulation and a contractility an order of magnitude higher than that of EPC as determined by traction force microscopy. Tissue-engineered blood vessels constructed using iSMC show functionality with respect to flow- and drug-mediated vasodilation and vasoconstriction. PMID:26874281

  13. Microenvironment influences vascular differentiation of murine cardiovascular progenitor cells.

    PubMed

    Gluck, Jessica M; Delman, Connor; Chyu, Jennifer; MacLellan, W Robb; Shemin, Richard J; Heydarkhan-Hagvall, Sepideh

    2014-11-01

    We examined the effects of the microenvironment on vascular differentiation of murine cardiovascular progenitor cells (CPCs). We isolated CPCs and seeded them in culture exposed to the various extracellular matrix (ECM) proteins in both two-dimensional (2D) and 3D culture systems. To better understand the contribution of the microenvironment to vascular differentiation, we analyzed endothelial and smooth muscle cell differentiation at both day 7 and day 14. We found that laminin and vitronectin enhanced vascular endothelial cell differentiation while fibronectin enhanced vascular smooth muscle cell differentiation. We also observed that the effects of the 3D electrospun scaffolds were delayed and not noticeable until the later time point (day 14), which may be due to the amount of time necessary for the cells to migrate to the interior of the scaffold. The study characterized the contributions of both ECM proteins and the addition of a 3D culture system to continued vascular differentiation. Additionally, we demonstrated the capability bioengineer a CPC-derived vascular graft. PMID:24687591

  14. l-Arginine is a Radioprotector for Hematopoietic Progenitor Cells

    PubMed Central

    Pearce, Linda L.; Zheng, Xichen; Martinez-Bosch, Sandra; Kerr, Patrick P.; Khlangwiset, Pornsri; Epperly, Michael W.; Fink, Mitchell P.; Greenberger, Joel S.; Peterson, Jim

    2012-01-01

    l-Arginine is shown to protect hematopoietic progenitor (32D cl 3) cells from death due to exposure to γ radiation (137Cs). Some of the other intermediates in the urea cycle, namely ornithine and citrulline, plus urea itself, were not found to have any significant impact on cell survival after irradiation. Intriguingly, supplementation of irradiated cells with l-arginine results in decreased production of peroxynitrite, suggesting that suppression of superoxide generation by nitric oxide synthase in one or more microenvironments is an important factor in the observed radioprotection. The absence of any radioprotective effect of l-arginine in cells at 3% oxygen also confirms the involvement of one or more oxygen-derived species. Knockdown experiments with nitric oxide synthase (NOS) siRNAs in cells and NOS knockout animals confirm that the observed radioprotection is associated with nNOS (NOS-1). l-Arginine also ameliorates the transient inhibition of the electron-transport chain complex I that occurs within 30 min of completing the dose (10 Gy) and that appears to be a functional marker for postirradiation mitochondrial oxidant production. PMID:22175298

  15. Circulating Progenitor and Mature Endothelial Cells in Deep Vein Thrombosis

    PubMed Central

    Alessio, Aline M; Beltrame, Miriam P; Nascimento, Mariane C Flores; Vicente, Cristina P; de Godoy, Juliana AP; Silva, Junia CR Santos; Bittar, Luis Fernando; Lorand-Metze, Irene; de Paula, Erich V; Annichino-Bizzacchi, Joyce M

    2013-01-01

    Introduction: Mature circulating endothelial cells (CEC) and circulating endothelial progenitor cells (EPC) have been described in several conditions associated with endothelial injury. Their role in deep vein thrombosis (DVT) has not been previously evaluated. Patients and Methods: In this pilot study we evaluated the time course of CEC and EPC release after vena cava experimental DVT in mice, using the FeCl3 model. We also evaluated their presence in patients with DVT at different phases of the disease (acute and chronic phase). CEC and EPC were evaluated by Flow Cytometry. Results: In mice, both CEC and EPC were increased 24 hours after DVT induction, peaking 48 hours thereafter. After 72 hours, CEC counts decreased sharply, whereas EPC counts decreased less substantially. In DVT patients we observed a significant increase in CEC counts immediately after DVT compared to healthy individuals. Patients with chronic disease also presented a significant elevation of these cell count. In a subgroup of patients for whom serial samples were available, CEC counts decreased significantly after 9-15 months of the acute event. Conclusions: Our results suggest the participation of these cells in the reparative processes that follows DVT, both at immediate and late time-points. The different kinetics of CEC and EPC release in experimental DVT suggests a heterogeneous role for these cells in the reparative events after DVT. PMID:24155660

  16. Type 2 Diabetes Dysregulates Glucose Metabolism in Cardiac Progenitor Cells.

    PubMed

    Salabei, Joshua K; Lorkiewicz, Pawel K; Mehra, Parul; Gibb, Andrew A; Haberzettl, Petra; Hong, Kyung U; Wei, Xiaoli; Zhang, Xiang; Li, Qianhong; Wysoczynski, Marcin; Bolli, Roberto; Bhatnagar, Aruni; Hill, Bradford G

    2016-06-24

    Type 2 diabetes is associated with increased mortality and progression to heart failure. Recent studies suggest that diabetes also impairs reparative responses after cell therapy. In this study, we examined potential mechanisms by which diabetes affects cardiac progenitor cells (CPCs). CPCs isolated from the diabetic heart showed diminished proliferation, a propensity for cell death, and a pro-adipogenic phenotype. The diabetic CPCs were insulin-resistant, and they showed higher energetic reliance on glycolysis, which was associated with up-regulation of the pro-glycolytic enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3). In WT CPCs, expression of a mutant form of PFKFB, which mimics PFKFB3 activity and increases glycolytic rate, was sufficient to phenocopy the mitochondrial and proliferative deficiencies found in diabetic cells. Consistent with activation of phosphofructokinase in diabetic cells, stable isotope carbon tracing in diabetic CPCs showed dysregulation of the pentose phosphate and glycero(phospho)lipid synthesis pathways. We describe diabetes-induced dysregulation of carbon partitioning using stable isotope metabolomics-based coupling quotients, which relate relative flux values between metabolic pathways. These findings suggest that diabetes causes an imbalance in glucose carbon allocation by uncoupling biosynthetic pathway activity, which could diminish the efficacy of CPCs for myocardial repair. PMID:27151219

  17. Effects of shear stress on endothelial progenitor cells.

    PubMed

    Obi, Syotaro; Yamamoto, Kimiko; Ando, Joji

    2014-10-01

    Endothelial progenitor cells (EPCs) are adult stem cells that play a central role in neovascularization. EPCs are mobilized from bone marrow into peripheral blood, attach to existing endothelial cells, and then transmigrate across the endothelium into tissues, where they proliferate, differentiate, and form new blood vessels. In the process, EPCs are exposed to shear stress, a biomechanical force generated by flowing blood and tissue fluid flow. When cultured EPCs are exposed to controlled levels of shear stress in a flow-loading device, their bioactivities in terms of proliferation, anti-apoptosis, migration, production of bioactive substances, anti-thrombosis, and tube formation increase markedly. Expression of endothelial marker genes and proteins by EPCs also increases in response to shear stress, and they differentiate into mature endothelial cells. Great advances have been made in elucidating the mechanisms by which mature endothelial cells sense and respond to shear stress, but not in EPCs. Further study of EPC responses to shear stress will be necessary to better understand the physiological and pathophysiological roles of EPCs and to apply EPCs to new therapies in the field of regenerative medicine. PMID:25992410

  18. Transcriptional Profiling of Bipotential Embryonic Liver Cells to Identify Liver Progenitor Cell Surface Markers

    PubMed Central

    Ochsner, Scott A.; Strick-Marchand, Hélène; Qiu, Qiong; Venable, Susan; Dean, Adam; Wilde, Margaret; Weiss, Mary C.; Darlington, Gretchen J.

    2010-01-01

    The ability to purify to homogeneity a population of hepatic progenitor cells from adult liver is critical for their characterization prior to any therapeutic application. As a step in this direction, we have used a bipotential liver cell line from 14 days postcoitum mouse embryonic liver to compile a list of cell surface markers expressed specifically by liver progenitor cells. These cells, known as bipotential mouse embryonic liver (BMEL) cells, proliferate in an undifferentiated state and are capable of differentiating into hepatocyte-like and cholangiocyte-like cells in vitro. Upon transplantation, BMEL cells are capable of differentiating into hepatocytes and cholangiocytes in vivo. Microarray and Gene Ontology (GO) analysis of gene expression in the 9A1 and 14B3 BMEL cell lines grown under proliferating and differentiating conditions was used to identify cell surface markers preferentially expressed in the bipotential undifferentiated state. This analysis revealed that proliferating BMEL cells express many genes involved in cell cycle regulation, whereas differentiation of BMEL cells by cell aggregation causes a switch in gene expression to functions characteristic of mature hepatocytes. In addition, microarray data and protein analysis indicated that the Notch signaling pathway could be involved in maintaining BMEL cells in an undifferentiated stem cell state. Using GO annotation, a list of cell surface markers preferentially expressed on undifferentiated BMEL cells was generated. One marker, Cd24a, is specifically expressed on progenitor oval cells in livers of diethyl 1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylate-treated animals. We therefore consider Cd24a expression a candidate molecule for purification of hepatic progenitor cells. PMID:17641245

  19. Foetal hepatic progenitor cells assume a cholangiocytic cell phenotype during two-dimensional pre-culture

    PubMed Central

    Anzai, Kazuya; Chikada, Hiromi; Tsuruya, Kota; Ida, Kinuyo; Kagawa, Tatehiro; Inagaki, Yutaka; Mine, Tesuya; Kamiya, Akihide

    2016-01-01

    Liver consists of parenchymal hepatocytes and other cells. Liver progenitor cell (LPC) is the origin of both hepatocytes and cholangiocytic cells. The analyses of mechanism regulating differentiation of LPCs into these functional cells are important for liver regenerative therapy using progenitor cells. LPCs in adult livers were found to form cysts with cholangiocytic characteristics in 3D culture. In contrast, foetal LPCs cannot form these cholangiocytic cysts in the same culture. Thus, the transition of foetal LPCs into cholangiocytic progenitor cells might occur during liver development. Primary CD45−Ter119−Dlk1+ LPCs derived from murine foetal livers formed ALBUMIN (ALB)+CYTOKERATIN (CK)19− non-cholangiocytic cysts within 3D culture. In contrast, when foetal LPCs were pre-cultured on gelatine-coated dishes, they formed ALB−CK19+ cholangiocytic cysts. When hepatocyte growth factor or oncostatin M, which are inducers of hepatocytic differentiation, was added to pre-culture, LPCs did not form cholangiocytic cysts. These results suggest that the pre-culture on gelatine-coated dishes changed the characteristics of foetal LPCs into cholangiocytic cells. Furthermore, neonatal liver progenitor cells were able to form cholangiocytic cysts in 3D culture without pre-culture. It is therefore possible that the pre-culture of mid-foetal LPCs in vitro functioned as a substitute for the late-foetal maturation step in vivo. PMID:27335264

  20. Low- and high-LET radiation drives clonal expansion of lung progenitor cells in vivo.

    PubMed

    Farin, Alicia M; Manzo, Nicholas D; Kirsch, David G; Stripp, Barry R

    2015-01-01

    Abundant populations of epithelial progenitor cells maintain the epithelium along the proximal-to-distal axis of the airway. Exposure of lung tissue to ionizing radiation leads to tissue remodeling and potential cancer initiation or progression. However, little is known about the effects of ionizing radiation on airway epithelial progenitor cells. We hypothesized that ionizing radiation exposure will alter the behavior of airway epithelial progenitor cells in a radiation dose- and quality-dependent manner. To address this hypothesis, we cultured primary airway epithelial cells isolated from mice exposed to various doses of 320 kVp X ray or 600 MeV/nucleon (56)Fe ions in a 3D epithelial-fibroblast co-culture system. Colony-forming efficiency of the airway epithelial progenitor cells was assessed at culture day 14. In vivo clonogenic and proliferative potentials of airway epithelial progenitor cells were measured after exposure to ionizing radiation by lineage tracing and IdU incorporation. Exposure to both X rays and (56)Fe resulted in a dose-dependent decrease in the ability of epithelial progenitors to form colonies in vitro. In vivo evidence for increased clonogenic expansion of epithelial progenitors was observed after exposure to both X rays and (56)Fe. Interestingly, we found no significant increase in the epithelial proliferative index, indicating that ionizing radiation does not promote increased turnover of the airway epithelium. Therefore, we propose a model in which radiation induces a dose-dependent decrease in the pool of available progenitor cells, leaving fewer progenitors able to maintain the airway long-term. This work provides novel insights into the effects of ionizing radiation exposure on airway epithelial progenitor cell behavior. PMID:25564721

  1. Single-cell gene expression profiling reveals functional heterogeneity of undifferentiated human epidermal cells

    PubMed Central

    Tan, David W. M.; Jensen, Kim B.; Trotter, Matthew W. B.; Connelly, John T.; Broad, Simon; Watt, Fiona M.

    2013-01-01

    Human epidermal stem cells express high levels of β1 integrins, delta-like 1 (DLL1) and the EGFR antagonist LRIG1. However, there is cell-to-cell variation in the relative abundance of DLL1 and LRIG1 mRNA transcripts. Single-cell global gene expression profiling showed that undifferentiated cells fell into two clusters delineated by expression of DLL1 and its binding partner syntenin. The DLL1+ cluster had elevated expression of genes associated with endocytosis, integrin-mediated adhesion and receptor tyrosine kinase signalling. Differentially expressed genes were not independently regulated, as overexpression of DLL1 alone or together with LRIG1 led to the upregulation of other genes in the DLL1+ cluster. Overexpression of DLL1 and LRIG1 resulted in enhanced extracellular matrix adhesion and increased caveolin-dependent EGFR endocytosis. Further characterisation of CD46, one of the genes upregulated in the DLL1+ cluster, revealed it to be a novel cell surface marker of human epidermal stem cells. Cells with high endogenous levels of CD46 expressed high levels of β1 integrin and DLL1 and were highly adhesive and clonogenic. Knockdown of CD46 decreased proliferative potential and β1 integrin-mediated adhesion. Thus, the previously unknown heterogeneity revealed by our studies results in differences in the interaction of undifferentiated basal keratinocytes with their environment. PMID:23482486

  2. Concise Review: Chemical Approaches for Modulating Lineage-Specific Stem Cells and Progenitors

    PubMed Central

    Xu, Tao; Zhang, Mingliang; Laurent, Timothy; Xie, Min

    2013-01-01

    Generation and manipulation of lineage-restricted stem and progenitor cells in vitro and/or in vivo are critical for the development of stem cell-based clinical therapeutics. Lineage-restricted stem and progenitor cells have many advantageous qualities, including being able to efficiently engraft and differentiate into desirable cell types in vivo after transplantation, and they are much less tumorigenic than pluripotent cells. Generation of lineage-restricted stem and progenitor cells can be achieved by directed differentiation from pluripotent stem cells or lineage conversion from easily obtained somatic cells. Small molecules can be very helpful in these processes since they offer several important benefits. For example, the risk of tumorigenesis is greatly reduced when small molecules are used to replace integrated transcription factors, which are widely used in cell fate conversion. Furthermore, small molecules are relatively easy to apply, optimize, and manufacture, and they can more readily be developed into conventional pharmaceuticals. Alternatively, small molecules can be used to expand or selectively control the differentiation of lineage-restricted stem and progenitor cells for desirable therapeutics purposes in vitro or in vivo. Here we summarize recent progress in the use of small molecules for the expansion and generation of desirable lineage-restricted stem and progenitor cells in vitro and for selectively controlling cell fate of lineage-restricted stem and progenitor cells in vivo, thereby facilitating stem cell-based clinical applications. PMID:23580542

  3. The zebrafish tailbud contains two independent populations of midline progenitor cells that maintain long-term germ layer plasticity and differentiate in response to local signaling cues.

    PubMed

    Row, Richard H; Tsotras, Steve R; Goto, Hana; Martin, Benjamin L

    2016-01-15

    Vertebrate body axis formation depends on a population of bipotential neuromesodermal cells along the posterior wall of the tailbud that make a germ layer decision after gastrulation to form spinal cord and mesoderm. Despite exhibiting germ layer plasticity, these cells never give rise to midline tissues of the notochord, floor plate and dorsal endoderm, raising the question of whether midline tissues also arise from basal posterior progenitors after gastrulation. We show in zebrafish that local posterior signals specify germ layer fate in two basal tailbud midline progenitor populations. Wnt signaling induces notochord within a population of notochord/floor plate bipotential cells through negative transcriptional regulation of sox2. Notch signaling, required for hypochord induction during gastrulation, continues to act in the tailbud to specify hypochord from a notochord/hypochord bipotential cell population. Our results lend strong support to a continuous allocation model of midline tissue formation in zebrafish, and provide an embryological basis for zebrafish and mouse bifurcated notochord phenotypes as well as the rare human congenital split notochord syndrome. We demonstrate developmental equivalency between the tailbud progenitor cell populations. Midline progenitors can be transfated from notochord to somite fate after gastrulation by ectopic expression of msgn1, a master regulator of paraxial mesoderm fate, or if transplanted into the bipotential progenitors that normally give rise to somites. Our results indicate that the entire non-epidermal posterior body is derived from discrete, basal tailbud cell populations. These cells remain receptive to extracellular cues after gastrulation and continue to make basic germ layer decisions. PMID:26674311

  4. MicroRNA-194 Regulates Hepatocytic Differentiation of Progenitor Cells by Targeting YAP1

    PubMed Central

    Jung, Kwang Hwa; McCarthy, Ryan L.; Zhou, Chong; Uprety, Nadima; Barton, Michelle Craig; Beretta, Laura

    2015-01-01

    MicroRNA expression profiling in human liver progenitor cells following hepatocytic differentiation identified miR-122 and miR-194 as the microRNAs most strongly upregulated during hepatocytic differentiation of progenitor cells. MiR-194 was also highly upregulated following hepatocytic differentiation of human embryonic stem cells (hESCs). Overexpression of miR-194 in progenitor cells accelerated their differentiation into hepatocytes, as measured by morphological features such as canaliculi and expression of hepatocytic markers. Overexpression of miR-194 in hESCs induced their spontaneous differentiation, a phenotype accompanied with accelerated loss of the pluripotent factors OCT4 and NANOG and decrease in mesoderm marker HAND1 expression. We then identified YAP1 as a direct target of miR-194. Inhibition of YAP1 strongly induced hepatocytic differentiation of progenitor cells and YAP1 over expression reversed the miR-194-induced hepatocytic differentiation of progenitor cells. In conclusion, we identified miR-194 as a potent inducer of hepatocytic differentiation of progenitor cells and further identified YAP1 as a mediator of miR-194's effects on hepatocytic differentiation and liver progenitor cell fate. PMID:26731713

  5. Progenitor cell maintenance and neurogenesis in sympathetic ganglia involves Notch signaling.

    PubMed

    Tsarovina, Konstantina; Schellenberger, Jens; Schneider, Carolin; Rohrer, Hermann

    2008-01-01

    Differentiation of noradrenergic neurons from neural crest-derived precursors results in the formation of primary sympathetic ganglia. As sympathetic neurons continue to divide after the acquisition of adrenergic and neuronal properties it was unclear, whether the increase in neuron number during neurogenesis is due to neuron proliferation rather than differentiation of progenitor cells. Here, we demonstrate Sox10-positive neural crest progenitor cells and continuous sympathetic neuron generation from Phox2b-positive autonomic progenitors during early chick sympathetic ganglion development. In vivo activation of Notch signaling resulted in a decreased neuronal population, whereas expression of the Notch signaling inhibitor Su(H)(DBM) increased the proportion of Scg10-positive neurons. Similar results were obtained for sensory dorsal root ganglia (DRG). The effects of Notch gain- and loss-of-function experiments support the notion that progenitor maintenance and neuron differentiation from progenitor cells are essential for neurogenesis also during early sympathetic ganglion development. PMID:17920293

  6. Interleukin 17 inhibits progenitor cells in rheumatoid arthritis cartilage.

    PubMed

    Schminke, Boris; Trautmann, Sandra; Mai, Burkhard; Miosge, Nicolai; Blaschke, Sabine

    2016-02-01

    Mesenchymal stem cells are known to exert immunomodulatory effects in inflammatory diseases. Immuneregulatory cells lead to progressive joint destruction in rheumatoid arthritis (RA). Proinflammatory cytokines, such as tumour necrosis factor α (TNF-α) and interleukins (ILs) are the main players. Here, we studied progenitor cells from RA cartilage (RA-CPCs) that are positive for IL-17 receptors to determinate the effects of inflammation on their chondrogenic potenial. IL-17A/F reduced the chondrogenic potential of these cells via the upregulation of RUNX2 protein and enhanced IL-6 protein and MMP3 mRNA levels. Blocking antibodies against IL-17 positively influenced their repair potential. Furthermore, treating the RA-CPCs with the anti-human IL-17 antibody secukinumab or the anti-TNF-α antibody adalimumab reduced the proinflammatory IL-6 protein level and positively influenced the secretion of anti-inflammatory IL-10 protein. Additionally, adalimumab and secukinumab in particular reduced RUNX2 protein to promote chondrogenesis. The amelioration of inflammation, particularly via IL-17 antagonism, might be a new therapeutic approach for enhancing intrinsic cartilage repair mechanisms in RA patients. PMID:26558442

  7. Epigenomic Reprogramming of Adult Cardiomyocyte-Derived Cardiac Progenitor Cells.

    PubMed

    Zhang, Yiqiang; Zhong, Jiang F; Qiu, Hongyu; MacLellan, W Robb; Marbán, Eduardo; Wang, Charles

    2015-01-01

    It has been believed that mammalian adult cardiomyocytes (ACMs) are terminally-differentiated and are unable to proliferate. Recently, using a bi-transgenic ACM fate mapping mouse model and an in vitro culture system, we demonstrated that adult mouse cardiomyocytes were able to dedifferentiate into cardiac progenitor-like cells (CPCs). However, little is known about the molecular basis of their intrinsic cellular plasticity. Here we integrate single-cell transcriptome and whole-genome DNA methylation analyses to unravel the molecular mechanisms underlying the dedifferentiation and cell cycle reentry of mouse ACMs. Compared to parental cardiomyocytes, dedifferentiated mouse cardiomyocyte-derived CPCs (mCPCs) display epigenomic reprogramming with many differentially-methylated regions, both hypermethylated and hypomethylated, across the entire genome. Correlated well with the methylome, our transcriptomic data showed that the genes encoding cardiac structure and function proteins are remarkably down-regulated in mCPCs, while those for cell cycle, proliferation, and stemness are significantly up-regulated. In addition, implantation of mCPCs into infarcted mouse myocardium improves cardiac function with augmented left ventricular ejection fraction. Our study demonstrates that the cellular plasticity of mammalian cardiomyocytes is the result of a well-orchestrated epigenomic reprogramming and a subsequent global transcriptomic alteration. PMID:26657817

  8. Epigenomic Reprogramming of Adult Cardiomyocyte-Derived Cardiac Progenitor Cells

    PubMed Central

    Zhang, Yiqiang; Zhong, Jiang F; Qiu, Hongyu; Robb MacLellan, W.; Marbán, Eduardo; Wang, Charles

    2015-01-01

    It has been believed that mammalian adult cardiomyocytes (ACMs) are terminally-differentiated and are unable to proliferate. Recently, using a bi-transgenic ACM fate mapping mouse model and an in vitro culture system, we demonstrated that adult mouse cardiomyocytes were able to dedifferentiate into cardiac progenitor-like cells (CPCs). However, little is known about the molecular basis of their intrinsic cellular plasticity. Here we integrate single-cell transcriptome and whole-genome DNA methylation analyses to unravel the molecular mechanisms underlying the dedifferentiation and cell cycle reentry of mouse ACMs. Compared to parental cardiomyocytes, dedifferentiated mouse cardiomyocyte-derived CPCs (mCPCs) display epigenomic reprogramming with many differentially-methylated regions, both hypermethylated and hypomethylated, across the entire genome. Correlated well with the methylome, our transcriptomic data showed that the genes encoding cardiac structure and function proteins are remarkably down-regulated in mCPCs, while those for cell cycle, proliferation, and stemness are significantly up-regulated. In addition, implantation of mCPCs into infarcted mouse myocardium improves cardiac function with augmented left ventricular ejection fraction. Our study demonstrates that the cellular plasticity of mammalian cardiomyocytes is the result of a well-orchestrated epigenomic reprogramming and a subsequent global transcriptomic alteration. PMID:26657817

  9. Myocardial infarction activates CCR2+ hematopoietic stem and progenitor cells

    PubMed Central

    Dutta, Partha; Sager, Hendrik B.; Stengel, Kristy R.; Naxerova, Kamila; Courties, Gabriel; Saez, Borja; Silberstein, Lev; Heidt, Timo; Sebas, Matthew; Sun, Yuan; Wojtkiewicz, Gregory; Feruglio, Paolo Fumene; King, Kevin; Baker, Joshua N.; van der Laan, Anja M.; Borodovsky, Anna; Fitzgerald, Kevin; Hulsmans, Maarten; Hoyer, Friedrich; Iwamoto, Yoshiko; Vinegoni, Claudio; Brown, Dennis; Di Carli, Marcelo; Libby, Peter; Hiebert, Scott; Scadden, David; Swirski, Filip K.; Weissleder, Ralph; Nahrendorf, Matthias

    2015-01-01

    SUMMARY Following myocardial infarction (MI), myeloid cells derived from the hematopoietic system drive a sharp increase in systemic leukocyte levels that correlate closely with mortality. The origin of these myeloid cells, and the response of hematopoietic stem and progenitor cells (HSPCs) to MI, however, is unclear. Here, we identify a CCR2+CD150+CD48− LSK hematopoietic subset as the most upstream contributor to emergency myelopoiesis after ischemic organ injury. CCR2+ HSPC have fourfold higher proliferation rates than CCR2−CD150+CD48− LSK cells, display a myeloid differentiation bias, and dominate the migratory HSPC population. We further demonstrate the myeloid translocation gene 16 (Mtg16) regulates CCR2+ HSPC emergence. Mtg16−/− mice have decreased levels of systemic monocytes and infarct-associated macrophages and display compromised tissue healing and post-MI heart failure. Together, these data provide insights into regulation of emergency hematopoiesis after ischemic injury, and identify potential therapeutic targets to modulate leukocyte output after MI. PMID:25957903

  10. Distribution and Characterization of Progenitor Cells within the Human Filum Terminale

    PubMed Central

    Jaff, Nasren; Ossoinak, Amina; Jansson, Katarina; Hägerstrand, Anders; Johansson, Clas B.; Brundin, Lou; Svensson, Mikael

    2011-01-01

    Background Filum terminale (FT) is a structure that is intimately associated with conus medullaris, the most caudal part of the spinal cord. It is well documented that certain regions of the adult human central nervous system contains undifferentiated, progenitor cells or multipotent precursors. The primary objective of this study was to describe the distribution and progenitor features of this cell population in humans, and to confirm their ability to differentiate within the neuroectodermal lineage. Methodology/Principal Findings We demonstrate that neural stem/progenitor cells are present in FT obtained from patients treated for tethered cord. When human or rat FT-derived cells were cultured in defined medium, they proliferated and formed neurospheres in 13 out of 21 individuals. Cells expressing Sox2 and Musashi-1 were found to outline the central canal, and also to be distributed in islets throughout the whole FT. Following plating, the cells developed antigen profiles characteristic of astrocytes (GFAP) and neurons (β-III-tubulin). Addition of PDGF-BB directed the cells towards a neuronal fate. Moreover, the cells obtained from young donors shows higher capacity for proliferation and are easier to expand than cells derived from older donors. Conclusion/Significance The identification of bona fide neural progenitor cells in FT suggests a possible role for progenitor cells in this extension of conus medullaris and may provide an additional source of such cells for possible therapeutic purposes. Filum terminale, human, progenitor cells, neuron, astrocytes, spinal cord. PMID:22096566

  11. Determining the Contribution of Epidermal Cell Shape to Petal Wettability Using Isogenic Antirrhinum Lines

    PubMed Central

    Whitney, Heather M.; Poetes, Rosa; Steiner, Ullrich; Chittka, Lars; Glover, Beverley J.

    2011-01-01

    The petal epidermis acts not only as a barrier to the outside world but also as a point of interaction between the flower and potential pollinators. The presence of conical petal epidermal cells has previously been shown to influence the attractiveness of the flower to pollinating insects. Using Antirrhinum isogenic lines differing only in the presence of a single epidermal structure, conical cells, we were able to investigate how the structure of the epidermis influences petal wettability by measuring the surface contact angle of water drops. Conical cells have a significant impact on how water is retained on the flower surface, which may have indirect consequences for pollinator behaviour. We discuss how the petal epidermis is a highly multifunctional one and how a battery of methods, including the use of isogenic lines, is required to untangle the impacts of specific epidermal properties in an ecological context. PMID:21423738

  12. Effective Mobilization of Very Small Embryonic-Like Stem Cells and Hematopoietic Stem/Progenitor Cells but Not Endothelial Progenitor Cells by Follicle-Stimulating Hormone Therapy

    PubMed Central

    Zbucka-Kretowska, Monika; Eljaszewicz, Andrzej; Lipinska, Danuta; Grubczak, Kamil; Rusak, Malgorzata; Mrugacz, Grzegorz; Dabrowska, Milena; Ratajczak, Mariusz Z.; Moniuszko, Marcin

    2016-01-01

    Recently, murine hematopoietic progenitor stem cells (HSCs) and very small embryonic-like stem cells (VSELs) were demonstrated to express receptors for sex hormones including follicle-stimulating hormone (FSH). This raised the question of whether FSH therapy at clinically applied doses can mobilize stem/progenitor cells in humans. Here we assessed frequencies of VSELs (referred to as Lin−CD235a−CD45−CD133+ cells), HSPCs (referred to as Lin−CD235a−CD45+CD133+ cells), and endothelial progenitor cells (EPCs, identified as CD34+CD144+, CD34+CD133+, and CD34+CD309+CD133+ cells) in fifteen female patients subjected to the FSH therapy. We demonstrated that FSH therapy resulted in statistically significant enhancement in peripheral blood (PB) number of both VSELs and HSPCs. In contrast, the pattern of responses of EPCs delineated by different cell phenotypes was not uniform and we did not observe any significant changes in EPC numbers following hormone therapy. Our data indicate that FSH therapy mobilizes VSELs and HSPCs into peripheral blood that on one hand supports their developmental origin from germ lineage, and on the other hand FSH can become a promising candidate tool for mobilizing HSCs and stem cells with VSEL phenotype in clinical settings. PMID:26635885

  13. Effective Mobilization of Very Small Embryonic-Like Stem Cells and Hematopoietic Stem/Progenitor Cells but Not Endothelial Progenitor Cells by Follicle-Stimulating Hormone Therapy.

    PubMed

    Zbucka-Kretowska, Monika; Eljaszewicz, Andrzej; Lipinska, Danuta; Grubczak, Kamil; Rusak, Malgorzata; Mrugacz, Grzegorz; Dabrowska, Milena; Ratajczak, Mariusz Z; Moniuszko, Marcin

    2016-01-01

    Recently, murine hematopoietic progenitor stem cells (HSCs) and very small embryonic-like stem cells (VSELs) were demonstrated to express receptors for sex hormones including follicle-stimulating hormone (FSH). This raised the question of whether FSH therapy at clinically applied doses can mobilize stem/progenitor cells in humans. Here we assessed frequencies of VSELs (referred to as Lin(-)CD235a(-)CD45(-)CD133(+) cells), HSPCs (referred to as Lin(-)CD235a(-)CD45(+)CD133(+) cells), and endothelial progenitor cells (EPCs, identified as CD34(+)CD144(+), CD34(+)CD133(+), and CD34(+)CD309(+)CD133(+) cells) in fifteen female patients subjected to the FSH therapy. We demonstrated that FSH therapy resulted in statistically significant enhancement in peripheral blood (PB) number of both VSELs and HSPCs. In contrast, the pattern of responses of EPCs delineated by different cell phenotypes was not uniform and we did not observe any significant changes in EPC numbers following hormone therapy. Our data indicate that FSH therapy mobilizes VSELs and HSPCs into peripheral blood that on one hand supports their developmental origin from germ lineage, and on the other hand FSH can become a promising candidate tool for mobilizing HSCs and stem cells with VSEL phenotype in clinical settings. PMID:26635885

  14. Persistence of skin-resident memory T cells within an epidermal niche.

    PubMed

    Zaid, Ali; Mackay, Laura K; Rahimpour, Azad; Braun, Asolina; Veldhoen, Marc; Carbone, Francis R; Manton, Jonathan H; Heath, William R; Mueller, Scott N

    2014-04-01

    Barrier tissues such as the skin contain various populations of immune cells that contribute to protection from infections. These include recently identified tissue-resident memory T cells (TRM). In the skin, these memory CD8(+) T cells reside in the epidermis after being recruited to this site by infection or inflammation. In this study, we demonstrate prolonged persistence of epidermal TRM preferentially at the site of prior infection despite sustained migration. Computational simulation of TRM migration within the skin over long periods revealed that the slow rate of random migration effectively constrains these memory cells within the region of skin in which they form. Notably, formation of TRM involved a concomitant local reduction in dendritic epidermal γδ T-cell numbers in the epidermis, indicating that these populations persist in mutual exclusion and may compete for local survival signals. Accordingly, we show that expression of the aryl hydrocarbon receptor, a transcription factor important for dendritic epidermal γδ T-cell maintenance in skin, also contributes to the persistence of skin TRM. Together, these data suggest that skin tissue-resident memory T cells persist within a tightly regulated epidermal T-cell niche. PMID:24706879

  15. Persistence of skin-resident memory T cells within an epidermal niche

    PubMed Central

    Zaid, Ali; Mackay, Laura K.; Rahimpour, Azad; Braun, Asolina; Veldhoen, Marc; Carbone, Francis R.; Manton, Jonathan H.; Heath, William R.; Mueller, Scott N.

    2014-01-01

    Barrier tissues such as the skin contain various populations of immune cells that contribute to protection from infections. These include recently identified tissue-resident memory T cells (TRM). In the skin, these memory CD8+ T cells reside in the epidermis after being recruited to this site by infection or inflammation. In this study, we demonstrate prolonged persistence of epidermal TRM preferentially at the site of prior infection despite sustained migration. Computational simulation of TRM migration within the skin over long periods revealed that the slow rate of random migration effectively constrains these memory cells within the region of skin in which they form. Notably, formation of TRM involved a concomitant local reduction in dendritic epidermal γδ T-cell numbers in the epidermis, indicating that these populations persist in mutual exclusion and may compete for local survival signals. Accordingly, we show that expression of the aryl hydrocarbon receptor, a transcription factor important for dendritic epidermal γδ T-cell maintenance in skin, also contributes to the persistence of skin TRM. Together, these data suggest that skin tissue-resident memory T cells persist within a tightly regulated epidermal T-cell niche. PMID:24706879

  16. [Epidermal cell cultures--significance for wound coverage in the human].

    PubMed

    Bonnekoh, B; Thiele, B; Mahrle, G; Steigleder, G K

    1986-10-15

    Epithelial sheets can be cultivated from isolated epidermal cells; in this way, it is possible to increase the cell number considerably. H. Green and co-workers were the first to make use of such epithelia for the autologous covering of burn wounds. We modified this method and report on our experiences with this technique in a patient with small skin defects. PMID:2432733

  17. Injury induces direct lineage segregation of functionally distinct airway basal stem/progenitor cell subpopulations.

    PubMed

    Pardo-Saganta, Ana; Law, Brandon M; Tata, Purushothama Rao; Villoria, Jorge; Saez, Borja; Mou, Hongmei; Zhao, Rui; Rajagopal, Jayaraj

    2015-02-01

    Following injury, stem cells restore normal tissue architecture by producing the proper number and proportions of differentiated cells. Current models of airway epithelial regeneration propose that distinct cytokeratin 8-expressing progenitor cells, arising from p63(+) basal stem cells, subsequently differentiate into secretory and ciliated cell lineages. We now show that immediately following injury, discrete subpopulations of p63(+) airway basal stem/progenitor cells themselves express Notch pathway components associated with either secretory or ciliated cell fate commitment. One basal cell population displays intracellular Notch2 activation and directly generates secretory cells; the other expresses c-myb and directly yields ciliated cells. Furthermore, disrupting Notch ligand activity within the basal cell population at large disrupts the normal pattern of lineage segregation. These non-cell-autonomous effects demonstrate that effective airway epithelial regeneration requires intercellular communication within the broader basal stem/progenitor cell population. These findings have broad implications for understanding epithelial regeneration and stem cell heterogeneity. PMID:25658372

  18. Examination of endothelial cell-induced epidermal regeneration in a mice-based chimney wound model.

    PubMed

    Seo, Joseph; Park, Soon-Jung; Choi, Jong-Jin; Kang, Sun-Woong; Lim, Joa-Jin; Lee, Hye-Jin; Kim, Jong-Soo; Yang, Heung-Mo; Kim, Sung-Joo; Kim, Eun-Young; Park, Se-Pil; Moon, Sung-Hwan; Chung, Hyung-Min

    2016-07-01

    As wound contraction in the cutaneous layer occurs rapidly in mice, mechanical means are typically used to deliberately expose the wound to properly investigate healing by secondary intention. Previously, silicon rings and splinting models were attempted to analyze histological recovery but prevention of surrounding epidermal cell migration and subsequent closure was minimal. Here, we developed an ideal chimney wound model to evaluate epidermal regeneration in murine under hESC-EC transplantation through histological analysis encompassing the three phases of regeneration: migration, proliferation, and remodeling. Human embryonic stem cell derived endothelial cells (hESC-EC) were transplanted due to possessing a well-known therapeutic effect in angiogenesis which also enhances epidermal repair to depict the process of regeneration. Following a standard 1 mm biopsy punch, a chimney manufactured by modifying a 1.7 mL microtube was simply inserted into the excisional wound to complete the modeling process. Under this model, the excisional wound remained fully exposed for 14 days and even after 4 weeks, only a thin transparent layer of epidermal tissue covered the wound site. This approach is able to more accurately depict epidermal repair in relation to histology while also being a user-friendly and cost-effective way to mimic human recovery in rodents and evaluate epithelial repair induced by a form of therapy. PMID:27237949

  19. Epidermal Merkel cells in psoriatic lesions: immunohistochemical investigations on neuroendocrine antigen expression.

    PubMed

    Wollina, U; Mahrle, G

    1992-05-01

    Biopsy specimens from lesional psoriatic skin and from normal controls were investigated by immunohistochemistry for the presence of epidermal Merkel cells (MC). MC were defined as epidermal cells expressing simple-type keratins, i.e. nos. 8, 18, and 19. A significant number of MC could be found at the bottom of the rete ridges of psoriatic lesions (about 19.6 MC per square mm skin surface area) and of normal skin (about 14.0 MC per square mm surface area). In contrast to normal skin, MC of psoriatic lesions were positive for synaptophysin (21.7% of simple-type keratin positive epidermal cells, i.e. MC), pancreatic polypeptide (14.8%), somatostatin (7.0%), and chromogranin A (less than 3%). The immunostaining was rather faint though significantly different from normal skin. The findings suggest that in psoriasis, epidermal MC show variations of the expression of neuropeptides compared to normal skin. Since some of the neuropeptides are thought to be involved in hyperproliferation and/or skin immunology, our findings might suggest a functional activity of epidermal MC in psoriatic lesions different from normal controls. PMID:1498093

  20. Efficient generation of retinal progenitor cells from human embryonic stem cells

    PubMed Central

    Lamba, Deepak A.; Karl, Mike O.; Ware, Carol B.; Reh, Thomas A.

    2006-01-01

    The retina is subject to degenerative conditions, leading to blindness. Although retinal regeneration is robust in lower vertebrates, regeneration does not occur in the adult mammalian retina. Thus, we have developed efficient methods for deriving retinal neurons from human embryonic stem (hES) cells. Under appropriate culture conditions, up to 80% of the H1 line can be directed to the retinal progenitor fate, and express a gene expression profile similar to progenitors derived from human fetal retina. The hES cell-derived progenitors differentiate primarily into inner retinal neurons (ganglion and amacrine cells), with functional glutamate receptors. Upon coculture with retinas derived from a mouse model of retinal degeneration, the hES cell derived retinal progenitors integrate with the degenerated mouse retina and increase in their expression of photoreceptor-specific markers. These results demonstrate that human ES cells can be selectively directed to a neural retinal cell fate and thus may be useful in the treatment of retinal degenerations. PMID:16908856

  1. Cardiac Progenitor Cell Commitment is Inhibited by Nuclear Akt Expression

    PubMed Central

    Fischer, Kimberlee M.; Din, Shabana; Gude, Natalie; Konstandin, Mathias H.; Wu, Weitao; Quijada, Pearl; Sussman, Mark A.

    2011-01-01

    Rationale Stem cell therapies to regenerate damaged cardiac tissue represent a novel approach to treat heart disease. However, the majority of adoptively transferred stem cells delivered to damaged myocardium do not survive long enough to impart protective benefits, resulting in modest functional improvements. Strategies to improve survival and proliferation of stem cells show promise for significantly enhancing cardiac function and regeneration. Objective Determine if injected cardiac progenitor cells (CPCs) genetically modified to overexpress nuclear Akt (CPCeA) increase structural and functional benefits to infarcted myocardium relative to control CPCs. Methods and Results CPCeA exhibit significantly increased proliferation and secretion of paracrine factors compared to CPCs. However, CPCeA exhibit impaired capacity for lineage commitment in vitro. Infarcted hearts receiving intramyocardial injection of CPCeA have increased recruitment of endogenous c-kit cells compared to CPCs, but neither population provides long-term functional and structural improvements compared to saline injected controls. Pharmacologic inhibition of Akt alleviated blockade of lineage commitment in CPCeA. Conclusions Although overexpression of nuclear Akt promotes rapid proliferation and secretion of protective paracrine factors, the inability of CPCeA to undergo lineage commitment hinders their capacity to provide functional or structural benefits to infarcted hearts. Despite enhanced recruitment of endogenous CPCs, lack of functional improvement in CPCeA treated hearts demonstrates CPC lineage commitment is essential to the regenerative response. Effective stem cell therapies must promote cellular survival and proliferation without inhibiting lineage commitment. Since CPCeA exhibit remarkable proliferative potential, an inducible system mediating nuclear Akt expression could be useful to augment cell therapy approaches. PMID:21350213

  2. Genetics Home Reference: epidermal nevus

    MedlinePlus

    ... primarily of a specific cell type called a keratinocyte. One group of epidermal nevi, called keratinocytic or nonorganoid epidermal nevi, includes nevi that involve only keratinocytes. Keratinocytic epidermal nevi are typically found on the ...

  3. Transformation of erythroid progenitors by viral and cellular tyrosine kinases.

    PubMed

    Beug, H; Schroeder, C; Wessely, O; Deiner, E; Meyer, S; Ischenko, I D; Hayman, M J

    1995-08-01

    Recently, two different normal avian erythroid progenitors were described. They differ in the receptor tyrosine kinases they express and in their ability to undergo self-renewal in culture. A common progenitor, termed stem cell factor (SCF) progenitor, expresses the receptor for avian SCF c-Kit, and undergoes short-term self-renewal when grown in the presence of avian SCF. A second progenitor, referred to as SCF/transforming growth factor-alpha progenitor, coexpresses c-Kit and the avian epidermal growth factor receptor homologue c-ErbB. These progenitors undergo sustained self-renewal when grown in the presence of transforming growth factor-alpha plus estradiol. The phenotype of the normal SCF/transforming growth factor-alpha progenitors closely corresponded to that of erythroid cells transformed by the tyrosine kinase oncogenes v-erbB or v-sea. This suggested that these cells, but not the SCF progenitors, would be the target cells for erythroblast transformation by these oncogenes. However, we demonstrate that both progenitor cells can be transformed by the v-erbB and v-sea oncogenes and also by the ligand-activated proto-oncogene product c-ErbB. We conclude that the target cell specificity of certain tyrosine kinase oncoproteins for erythroid cells is a reflection of their ability to provide signals for self-renewal that normally emanate from the endogenous c-ErbB protein. PMID:8547228

  4. Therapeutic Roles of Tendon Stem/Progenitor Cells in Tendinopathy

    PubMed Central

    Zhang, Xin; Lin, Yu-cheng; Rui, Yun-feng; Xu, Hong-liang; Chen, Hui; Wang, Chen; Teng, Gao-jun

    2016-01-01

    Tendinopathy is a tendon disorder characterized by activity-related pain, local edema, focal tenderness to palpation, and decreased strength in the affected area. Tendinopathy is prevalent in both athletes and the general population, highlighting the need to elucidate the pathogenesis of this disorder. Current treatments of tendinopathy are both conservative and symptomatic. The discovery of tendon stem/progenitor cells (TSPCs) and erroneous differentiation of TSPCs have provided new insights into the pathogenesis of tendinopathy. In this review, we firstly present the histopathological characteristics of tendinopathy and explore the cellular and molecular cues in the pathogenesis of tendinopathy. Current evidence of the depletion of the stem cell pool and altered TSPCs fate in the pathogenesis of tendinopathy has been presented. The potential regulatory factors for either tenogenic or nontenogenic differentiation of TSPCs are also summarized. The regulation of endogenous TSPCs or supplementation with exogenous TSPCs as therapeutic targets for the treatment of tendinopathy is proposed. Therefore, inhibiting the erroneous differentiation of TSPCs and regulating the differentiation of TSPCs into tendon cells might be important areas of future research and could provide new clinical treatments for tendinopathy. The current evidence suggests that TSPCs are promising therapeutic targets for the management of tendinopathy. PMID:27195010

  5. Endothelial progenitor cells regenerate infracted myocardium with neovascularisation development.

    PubMed

    Abd El Aziz, M T; Abd El Nabi, E A; Abd El Hamid, M; Sabry, D; Atta, H M; Rahed, L A; Shamaa, A; Mahfouz, S; Taha, F M; Elrefaay, S; Gharib, D M; Elsetohy, Khaled A

    2015-03-01

    We achieved possibility of isolation, characterization human umbilical cord blood endothelial progenitor cells (EPCs), examination potency of EPCs to form new blood vessels and differentiation into cardiomyoctes in canines with acute myocardial infarction (AMI). EPCs were separated and cultured from umbilical cord blood. Their phenotypes were confirmed by uptake of double stains dioctadecyl tetramethylindocarbocyanine-labeled acetylated LDL and FITC-labeled Ulex europaeus agglutinin 1 (DILDL-UEA-1). EPCs of cord blood were counted. Human VEGFR-2 and eNOS from the cultured EPCs were assessed by qPCR. Human EPCs was transplanted intramyocardially in canines with AMI. ECG and cardiac enzymes (CK-MB and Troponin I) were measured to assess severity of cellular damage. Histopathology was done to assess neovascularisation. Immunostaining was done to detect EPCs transdifferentiation into cardiomyocytes in peri-infarct cardiac tissue. qPCR for human genes (hVEGFR-2, and eNOS) was done to assess homing and angiogenic function of transplanted EPCs. Cultured human cord blood exhibited an increased number of EPCs and significant high expression of hVEGFR-2 and eNOS genes in the culture cells. Histopathology showed increased neovascularization and immunostaining showed presence of EPCs newly differentiated into cardiomyocyte-like cells. Our findings suggested that hEPCs can mediate angiogenesis and differentiate into cardiomyoctes in canines with AMI. PMID:25750747

  6. Endothelial progenitor cells regenerate infracted myocardium with neovascularisation development☆

    PubMed Central

    Abd El Aziz, M.T.; Abd El Nabi, E.A.; Abd El Hamid, M.; Sabry, D.; Atta, H.M.; Rahed, L.A.; Shamaa, A.; Mahfouz, S.; Taha, F.M.; Elrefaay, S.; Gharib, D.M.; Elsetohy, Khaled A.

    2013-01-01

    We achieved possibility of isolation, characterization human umbilical cord blood endothelial progenitor cells (EPCs), examination potency of EPCs to form new blood vessels and differentiation into cardiomyoctes in canines with acute myocardial infarction (AMI). EPCs were separated and cultured from umbilical cord blood. Their phenotypes were confirmed by uptake of double stains dioctadecyl tetramethylindocarbocyanine-labeled acetylated LDL and FITC-labeled Ulex europaeus agglutinin 1 (DILDL-UEA-1). EPCs of cord blood were counted. Human VEGFR-2 and eNOS from the cultured EPCs were assessed by qPCR. Human EPCs was transplanted intramyocardially in canines with AMI. ECG and cardiac enzymes (CK-MB and Troponin I) were measured to assess severity of cellular damage. Histopathology was done to assess neovascularisation. Immunostaining was done to detect EPCs transdifferentiation into cardiomyocytes in peri-infarct cardiac tissue. qPCR for human genes (hVEGFR-2, and eNOS) was done to assess homing and angiogenic function of transplanted EPCs. Cultured human cord blood exhibited an increased number of EPCs and significant high expression of hVEGFR-2 and eNOS genes in the culture cells. Histopathology showed increased neovascularization and immunostaining showed presence of EPCs newly differentiated into cardiomyocyte-like cells. Our findings suggested that hEPCs can mediate angiogenesis and differentiate into cardiomyoctes in canines with AMI. PMID:25750747

  7. Estrogen Stimulates Homing of Endothelial Progenitor Cells to Endometriotic Lesions.

    PubMed

    Rudzitis-Auth, Jeannette; Nenicu, Anca; Nickels, Ruth M; Menger, Michael D; Laschke, Matthias W

    2016-08-01

    The incorporation of endothelial progenitor cells (EPCs) into microvessels contributes to the vascularization of endometriotic lesions. Herein, we analyzed whether this vasculogenic process is regulated by estrogen. Estrogen- and vehicle-treated human EPCs were analyzed for migration and tube formation. Endometriotic lesions were induced in irradiated FVB/N mice, which were reconstituted with bone marrow from FVB/N-TgN (Tie2/green fluorescent protein) 287 Sato mice. The animals were treated with 100 μg/kg β-estradiol 17-valerate or vehicle (control) over 7 and 28 days. Lesion growth, cyst formation, homing of green fluorescent protein(+)/Tie2(+) EPCs, vascularization, cell proliferation, and apoptosis were analyzed by high-resolution ultrasonography, caliper measurements, histology, and immunohistochemistry. Numbers of blood circulating EPCs were assessed by flow cytometry. In vitro, estrogen-treated EPCs exhibited a higher migratory and tube-forming capacity when compared with controls. In vivo, numbers of circulating EPCs were not affected by estrogen. However, estrogen significantly increased the number of EPCs incorporated into the lesions' microvasculature, resulting in an improved early vascularization. Estrogen further stimulated the growth of lesions, which exhibited massively dilated glands with a flattened layer of stroma. This was mainly because of an increased glandular secretory activity, whereas cell proliferation and apoptosis were not markedly affected. These findings indicate that vasculogenesis in endometriotic lesions is dependent on estrogen, which adds a novel hormonally regulated mechanism to the complex pathophysiology of endometriosis. PMID:27315780

  8. Mpath maps multi-branching single-cell trajectories revealing progenitor cell progression during development

    PubMed Central

    Chen, Jinmiao; Schlitzer, Andreas; Chakarov, Svetoslav; Ginhoux, Florent; Poidinger, Michael

    2016-01-01

    Single-cell RNA-sequencing offers unprecedented resolution of the continuum of state transition during cell differentiation and development. However, tools for constructing multi-branching cell lineages from single-cell data are limited. Here we present Mpath, an algorithm that derives multi-branching developmental trajectories using neighborhood-based cell state transitions. Applied to mouse conventional dendritic cell (cDC) progenitors, Mpath constructs multi-branching trajectories spanning from macrophage/DC progenitors through common DC progenitor to pre-dendritic cells (preDC). The Mpath-generated trajectories detect a branching event at the preDC stage revealing preDC subsets that are exclusively committed to cDC1 or cDC2 lineages. Reordering cells along cDC development reveals sequential waves of gene regulation and temporal coupling between cell cycle and cDC differentiation. Applied to human myoblasts, Mpath recapitulates the time course of myoblast differentiation and isolates a branch of non-muscle cells involved in the differentiation. Our study shows that Mpath is a useful tool for constructing cell lineages from single-cell data. PMID:27356503

  9. Mpath maps multi-branching single-cell trajectories revealing progenitor cell progression during development.

    PubMed

    Chen, Jinmiao; Schlitzer, Andreas; Chakarov, Svetoslav; Ginhoux, Florent; Poidinger, Michael

    2016-01-01

    Single-cell RNA-sequencing offers unprecedented resolution of the continuum of state transition during cell differentiation and development. However, tools for constructing multi-branching cell lineages from single-cell data are limited. Here we present Mpath, an algorithm that derives multi-branching developmental trajectories using neighborhood-based cell state transitions. Applied to mouse conventional dendritic cell (cDC) progenitors, Mpath constructs multi-branching trajectories spanning from macrophage/DC progenitors through common DC progenitor to pre-dendritic cells (preDC). The Mpath-generated trajectories detect a branching event at the preDC stage revealing preDC subsets that are exclusively committed to cDC1 or cDC2 lineages. Reordering cells along cDC development reveals sequential waves of gene regulation and temporal coupling between cell cycle and cDC differentiation. Applied to human myoblasts, Mpath recapitulates the time course of myoblast differentiation and isolates a branch of non-muscle cells involved in the differentiation. Our study shows that Mpath is a useful tool for constructing cell lineages from single-cell data. PMID:27356503

  10. HDAC3 is essential for DNA replication in hematopoietic progenitor cells

    PubMed Central

    Summers, Alyssa R.; Fischer, Melissa A.; Stengel, Kristy R.; Zhao, Yue; Kaiser, Jonathan F.; Wells, Christina E.; Hunt, Aubrey; Bhaskara, Srividya; Luzwick, Jessica W.; Sampathi, Shilpa; Chen, Xi; Thompson, Mary Ann; Cortez, David; Hiebert, Scott W.

    2013-01-01

    Histone deacetylase 3 (HDAC3) contributes to the regulation of gene expression, chromatin structure, and genomic stability. Because HDAC3 associates with oncoproteins that drive leukemia and lymphoma, we engineered a conditional deletion allele in mice to explore the physiological roles of Hdac3 in hematopoiesis. We used the Vav-Cre transgenic allele to trigger recombination, which yielded a dramatic loss of lymphoid cells, hypocellular bone marrow, and mild anemia. Phenotypic and functional analysis suggested that Hdac3 was required for the formation of the earliest lymphoid progenitor cells in the marrow, but that the marrow contained 3–5 times more multipotent progenitor cells. Hdac3–/– stem cells were severely compromised in competitive bone marrow transplantation. In vitro, Hdac3–/– stem and progenitor cells failed to proliferate, and most cells remained undifferentiated. Moreover, one-third of the Hdac3–/– stem and progenitor cells were in S phase 2 hours after BrdU labeling in vivo, suggesting that these cells were impaired in transit through the S phase. DNA fiber-labeling experiments indicated that Hdac3 was required for efficient DNA replication in hematopoietic stem and progenitor cells. Thus, Hdac3 is required for the passage of hematopoietic stem/progenitor cells through the S phase, for stem cell functions, and for lymphopoiesis. PMID:23921131

  11. Nucleostemin Rejuvenates Cardiac Progenitor Cells and Antagonizes Myocardial Aging

    PubMed Central

    Hariharan, Nirmala; Quijada, Pearl; Mohsin, Sadia; Joyo, Anya; Samse, Kaitlen; Monsanto, Megan; De La Torre, Andrea; Avitabile, Daniele; Ormachea, Lucia; McGregor, Michael J.; Tsai, Emily J; Sussman, Mark A.

    2015-01-01

    BACKGROUND Functional decline in stem cell-mediated regeneration contributes to aging associated with cellular senescence in c-kit+ cardiac progenitor cells (CPCs). Clinical implementation of CPC-based therapy with elderly patients would benefit tremendously from understanding molecular characteristics of senescence to antagonize aging. Nucleostemin (NS) is a nucleolar protein regulating stem cell proliferation and pluripotency. OBJECTIVES The goal is to demonstrate that NS preserves characteristics associated with “stemness” in CPCs and antagonizes myocardial senescence and aging. METHODS CPCs isolated from human fetal (FhCPC) and adult failing (AhCPC) hearts, as well as young (YCPC) and old mice (OCPC), were studied for senescence characteristics and NS expression. Heterozygous knockout mice with one functional allele of NS (NS+/−) were used to demonstrate that NS preserves myocardial structure and function and slows characteristics of aging. RESULTS NS expression is decreased in AhCPCs relative to FhCPC, correlating with lowered proliferation potential and shortened telomere length. AhCPC characteristics resemble OCPCs, which have a phenotype induced by NS silencing, resulting in cell flattening, senescence, multinucleated cells, decreased S phase progression, diminished expression of stemness markers and up-regulation of p53 and p16. CPC senescence resulting from NS loss is partially p53 dependent and is rescued by concurrent silencing of p53. Mechanistically, NS induction correlates with Pim-1 kinase-mediated stabilization of c-Myc. Engineering OCPCs and AhCPCs to overexpress NS decreases senescent and multinucleated cells, restores morphology, and antagonizes senescence, thereby preserving phenotypic properties of “stemness.” Early cardiac aging with decline in cardiac function, increase in senescence markers p53 and p16, telomere attrition, and accompanied CPC exhaustion is evident in NS+/− mice. CONCLUSIONS Youthful properties and antagonism of

  12. Heterogeneity of neural progenitor cells revealed by enhancers in the nestin gene

    PubMed Central

    Yaworsky, Paul J.; Kappen, Claudia

    2014-01-01

    Using transgenic embryos, we have identified two distinct CNS progenitor cell-specific enhancers, each requiring the cooperation of at least two independent regulatory sites, within the second intron of the rat nestin gene. One enhancer is active throughout the developing CNS while the other is specifically active in the ventral midbrain. These experiments demonstrate that neural progenitor cells in the midbrain constitute a unique subpopulation based upon their ability to activate the midbrain regulatory elements. Our finding of differential enhancer activity from a gene encoding a structural protein reveals a previously unrecognized diversity in neural progenitor cell populations. PMID:9917366

  13. A rapid procedure for flow cytometric DNA analysis in cultures of normal and transformed epidermal cells.

    PubMed

    Tennenbaum, T; Giloh, H; Fusenig, N E; Kapitulnik, J

    1988-06-01

    A simple, rapid, and highly reproducible procedure for flow cytometric DNA analysis has been adapted for studying cell cycle kinetics in epidermal cell cultures. The preparation of cell nuclei and their staining with the fluorescent dye propidium iodide were performed directly on the culture dish, without prior suspension and fixation of the cells. Singly dispersed nuclei were produced by mild trypsinization of cells in the presence of the nonionic detergent Nonidet P-40 and spermine. The culture dishes could be kept frozen for prolonged periods of time before trypsinization and staining, without affecting either the recovery of nuclei or the cell cycle distribution profiles. This remarkable stability of cell nuclei greatly simplified the analysis of multiple samples in cell cycle kinetic studies. This method was used to analyze the cell cycle distribution in cultures of normal and transformed mouse epidermal cells, human colon carcinoma cells, primary bovine aortic endothelial cells, and fibroblastic and myogenic cell lines. This procedure should be very useful in studying growth kinetics, differentiation, and transformation of epidermal as well as other adherent cell types. PMID:2453587

  14. Epigenetic therapy of cancer stem and progenitor cells by targeting DNA methylation machineries.

    PubMed

    Wongtrakoongate, Patompon

    2015-01-26

    Recent advances in stem cell biology have shed light on how normal stem and progenitor cells can evolve to acquire malignant characteristics during tumorigenesis. The cancer counterparts of normal stem and progenitor cells might be occurred through alterations of stem cell fates including an increase in self-renewal capability and a decrease in differentiation and/or apoptosis. This oncogenic evolution of cancer stem and progenitor cells, which often associates with aggressive phenotypes of the tumorigenic cells, is controlled in part by dysregulated epigenetic mechanisms including aberrant DNA methylation leading to abnormal epigenetic memory. Epigenetic therapy by targeting DNA methyltransferases (DNMT) 1, DNMT3A and DNMT3B via 5-Azacytidine (Aza) and 5-Aza-2'-deoxycytidine (Aza-dC) has proved to be successful toward treatment of hematologic neoplasms especially for patients with myelodysplastic syndrome. In this review, I summarize the current knowledge of mechanisms underlying the inhibition of DNA methylation by Aza and Aza-dC, and of their apoptotic- and differentiation-inducing effects on cancer stem and progenitor cells in leukemia, medulloblastoma, glioblastoma, neuroblastoma, prostate cancer, pancreatic cancer and testicular germ cell tumors. Since cancer stem and progenitor cells are implicated in cancer aggressiveness such as tumor formation, progression, metastasis and recurrence, I propose that effective therapeutic strategies might be achieved through eradication of cancer stem and progenitor cells by targeting the DNA methylation machineries to interfere their "malignant memory". PMID:25621113

  15. Increased symplasmic permeability in barley root epidermal cells correlates with defects in root hair development.

    PubMed

    Marzec, M; Muszynska, A; Melzer, M; Sas-Nowosielska, H; Kurczynska, E U

    2014-03-01

    It is well known that the process of plant cell differentiation depends on the symplasmic isolation of cells. Before starting the differentiation programme, the individual cell or group of cells should restrict symplasmic communication with neighbouring cells. We tested the symplasmic communication between epidermal cells in the different root zones of parental barley plants Hordeum vulgare L., cv. 'Karat' with normal root hair development, and two root hairless mutants (rhl1.a and rhl1.b). The results clearly show that symplasmic communication was limited during root hair differentiation in the parental variety, whereas in both root hairless mutants epidermal cells were still symplasmically connected in the corresponding root zone. This paper is the first report on the role of symplasmic isolation in barley root cell differentiation, and additionally shows that a disturbance in the restriction of symplasmic communication is present in root hairless mutants. PMID:23927737

  16. Increased symplasmic permeability in barley root epidermal cells correlates with defects in root hair development

    PubMed Central

    Marzec, M; Muszynska, A; Melzer, M; Sas-Nowosielska, H; Kurczynska, E U; Wick, S

    2014-01-01

    It is well known that the process of plant cell differentiation depends on the symplasmic isolation of cells. Before starting the differentiation programme, the individual cell or group of cells should restrict symplasmic communication with neighbouring cells. We tested the symplasmic communication between epidermal cells in the different root zones of parental barley plants Hordeum vulgare L., cv. ‘Karat’ with normal root hair development, and two root hairless mutants (rhl1.a and rhl1.b). The results clearly show that symplasmic communication was limited during root hair differentiation in the parental variety, whereas in both root hairless mutants epidermal cells were still symplasmically connected in the corresponding root zone. This paper is the first report on the role of symplasmic isolation in barley root cell differentiation, and additionally shows that a disturbance in the restriction of symplasmic communication is present in root hairless mutants. PMID:23927737

  17. Epidermal cell proliferation in guinea pigs with experimental dermatophytosis

    SciTech Connect

    Tagami, H.

    1985-08-01

    To elucidate the mechanisms underlying the self-healing process of experimental dermatophytosis produced in guinea pigs by an occlusive method with Trichophyton mentagrophytes, epidermal proliferative activity was evaluated by the in vivo tritiated thymidine-labeling technique performed at various intervals after the first and second infections. Determination of labeling indices disclosed that an increased epidermal proliferation correlated well with the severity of inflammatory changes, i.e., a peak activity was noted after 10 days in primary infection and at 2 days in reinfection, respectively, and was followed by subsequent spontaneous lesion clearance after 10 days. Application of a heat-killed spore suspension produced inflammatory changes with enhanced epidermopoiesis, similar to those induced by reinoculation of living spores, only in immune animals. The present results indicate that the dermatitic changes occurring in experimental dermatophytosis increase epidermopoiesis which facilitates elimination of the fungus from the stratum corneum and that host immune activity, particularly contact sensitivity to fungal antigen, exerts a crucial role to induce these changes.

  18. Fetal Leydig Cells: Progenitor Cell Review Maintenance and Differentiation

    PubMed Central

    BARSOUM, IVRAYM B.; YAO, HUMPHREY H.-C.

    2012-01-01

    In most eutherian mammals, sexually dimorphic masculinization is established by androgen-producing fetal Leydig cells in the embryonic testis. Fetal Leydig cells, which lack expression of the testis-determining gene SRY, arise after the appearance of SRY-expressing Sertoli cells. Therefore, the appearance and differentiation of fetal Leydig cells are probably regulated by factors derived from Sertoli cells. Results from mouse genetic models have revealed that maintenance and differentiation of fetal Leydig cell population depends upon a balance between differentiation-promoting and differentiation-suppressing mechanisms. Although paracrine signaling via Sertoli cell–derived Hedgehog ligands is necessary and sufficient for fetal Leydig cell formation, cell-cell interaction via Notch signaling and intracellular transcription factors such as POD1 are implicated as suppressors of fetal Leydig cell differentiation. This review provides a model that summarizes the recent findings in fetal Leydig cell development. PMID:19875489

  19. Stem/Progenitor Cell Niches Involved in Hepatic and Biliary Regeneration

    PubMed Central

    Carpino, Guido; Renzi, Anastasia; Franchitto, Antonio; Cardinale, Vincenzo; Onori, Paolo; Reid, Lola; Alvaro, Domenico; Gaudio, Eugenio

    2016-01-01

    Niches containing stem/progenitor cells are present in different anatomical locations along the human biliary tree and within liver acini. The most primitive stem/progenitors, biliary tree stem/progenitor cells (BTSCs), reside within peribiliary glands located throughout large extrahepatic and intrahepatic bile ducts. BTSCs are multipotent and can differentiate towards hepatic and pancreatic cell fates. These niches' matrix chemistry and other characteristics are undefined. Canals of Hering (bile ductules) are found periportally and contain hepatic stem/progenitor cells (HpSCs), participating in the renewal of small intrahepatic bile ducts and being precursors to hepatocytes and cholangiocytes. The niches also contain precursors to hepatic stellate cells and endothelia, macrophages, and have a matrix chemistry rich in hyaluronans, minimally sulfated proteoglycans, fetal collagens, and laminin. The microenvironment furnishes key signals driving HpSC activation and differentiation. Newly discovered third niches are pericentral within hepatic acini, contain Axin2+ unipotent hepatocytic progenitors linked on their lateral borders to endothelia forming the central vein, and contribute to normal turnover of mature hepatocytes. Their relationship to the other stem/progenitors is undefined. Stem/progenitor niches have important implications in regenerative medicine for the liver and biliary tree and in pathogenic processes leading to diseases of these tissues. PMID:26880956

  20. Neural stem/progenitor cells in Alzheimer’s disease

    PubMed Central

    Tincer, Gizem; Mashkaryan, Violeta; Bhattarai, Prabesh; Kizil, Caghan

    2016-01-01

    Alzheimer’s disease (AD) is the most prevalent neurodegenerative disease and a worldwide health challenge. Different therapeutic approaches are being developed to reverse or slow the loss of affected neurons. Another plausible therapeutic way that may complement the studies is to increase the survival of existing neurons by mobilizing the existing neural stem/progenitor cells (NSPCs) — i.e. “induce their plasticity” — to regenerate lost neurons despite the existing pathology and unfavorable environment. However, there is controversy about how NSPCs are affected by the unfavorable toxic environment during AD. In this review, we will discuss the use of stem cells in neurodegenerative diseases and in particular how NSPCs affect the AD pathology and how neurodegeneration affects NSPCs. In the end of this review, we will discuss how zebrafish as a useful model organism with extensive regenerative ability in the brain might help to address the molecular programs needed for NSPCs to respond to neurodegeneration by enhanced neurogenesis. PMID:27505014

  1. Endothelial progenitor cell recruitment in a microfluidic vascular model.

    PubMed

    Lewis, Daniel M; Abaci, Hasan E; Xu, Yu; Gerecht, Sharon

    2015-12-01

    During vessel injury, endothelial progenitors cells (EPCs) are recruited from bone marrow and directed to the hypoxic injury site. The hypoxic conditions in the damaged blood vessel promote TNF-α, which upregulates intercellular adhesion molecule-1 (ICAM-1). EPCs attach to endothelial cell lining using ICAM-1. Here we aimed to examine EPC attachment to ECs in an injured-blood vessel conditions. We first determined ICAM-1 expression in stimulated HUVECs. We stimulated HUVECs with 21% oxygen (atmospheric), atmospheric with TNF-α-supplemented media, 1% oxygen (hypoxia), and hypoxia with TNF-α-supplemented media and found the highest ECFC attachment on HUVECs stimulated with TNF-α and hypoxia, correlating with the highest ICAM-1 expression. We next designed, fabricated and tested a three-dimensional microbioreactor (3D MBR) system with precise control and monitoring of dissolve oxygen and media flow rate in the cellular environment. We utilized a step-wise seeding approach, producing monolayer of HUVECs on all four walls. When stimulated with both TNF-α and hypoxia, ECFC retention on HUVECs was significantly increased under low shear stress compared to static controls. Overall, the 3D MBR system mimics the pathological oxygen tension and shear stress in the damaged vasculature, providing a platform to model vascular-related disorders. PMID:26693599

  2. Genomic characterization of Wilms' tumor suppressor 1 targets in nephron progenitor cells during kidney development

    PubMed Central

    Hartwig, Sunny; Ho, Jacqueline; Pandey, Priyanka; MacIsaac, Kenzie; Taglienti, Mary; Xiang, Michael; Alterovitz, Gil; Ramoni, Marco; Fraenkel, Ernest; Kreidberg, Jordan A.

    2010-01-01

    Summary The Wilms' tumor suppressor 1 (WT1) gene encodes a DNA- and RNA-binding protein that plays an essential role in nephron progenitor differentiation during renal development. To identify WT1 target genes that might regulate nephron progenitor differentiation in vivo, we performed chromatin immunoprecipitation (ChIP) coupled to mouse promoter microarray (ChIP-chip) using chromatin prepared from embryonic mouse kidney tissue. We identified 1663 genes bound by WT1, 86% of which contain a previously identified, conserved, high-affinity WT1 binding site. To investigate functional interactions between WT1 and candidate target genes in nephron progenitors, we used a novel, modified WT1 morpholino loss-of-function model in embryonic mouse kidney explants to knock down WT1 expression in nephron progenitors ex vivo. Low doses of WT1 morpholino resulted in reduced WT1 target gene expression specifically in nephron progenitors, whereas high doses of WT1 morpholino arrested kidney explant development and were associated with increased nephron progenitor cell apoptosis, reminiscent of the phenotype observed in Wt1−/− embryos. Collectively, our results provide a comprehensive description of endogenous WT1 target genes in nephron progenitor cells in vivo, as well as insights into the transcriptional signaling networks controlled by WT1 that might direct nephron progenitor fate during renal development. PMID:20215353

  3. Human mammary progenitor cell fate decisions are products of interactions with combinatorial microenvironments

    SciTech Connect

    LaBarge, Mark A; Nelson, Celeste M; Villadsen, Rene; Fridriksdottir, Agla; Ruth, Jason R; Stampfer, Martha R; Petersen, Ole W; Bissell, Mina J

    2008-09-19

    In adult tissues, multi-potent progenitor cells are some of the most primitive members of the developmental hierarchies that maintain homeostasis. That progenitors and their more mature progeny share identical genomes, suggests that fate decisions are directed by interactions with extrinsic soluble factors, ECM, and other cells, as well as physical properties of the ECM. To understand regulation of fate decisions, therefore, would require a means of understanding carefully choreographed combinatorial interactions. Here we used microenvironment protein microarrays to functionally identify combinations of cell-extrinsic mammary gland proteins and ECM molecules that imposed specific cell fates on bipotent human mammary progenitor cells. Micropatterned cell culture surfaces were fabricated to distinguish between the instructive effects of cell-cell versus cell-ECM interactions, as well as constellations of signaling molecules; and these were used in conjunction with physiologically relevant 3 dimensional human breast cultures. Both immortalized and primary human breast progenitors were analyzed. We report on the functional ability of those proteins of the mammary gland that maintain quiescence, maintain the progenitor state, and guide progenitor differentiation towards myoepithelial and luminal lineages.

  4. Adrenocortical Cells with Stem/Progenitor Cell Properties: Recent Advances

    PubMed Central

    Kim, Alex; Hammer, Gary D.

    2007-01-01

    The existence and location of undifferentiated cells with the capability of maintaining the homeostasis of the adrenal cortex have long been sought. These cells are thought to remain mostly quiescent with a potential to commit to self-renewal processes or terminal differentiation to homeostatically repopulate the organ. In addition, in response to physiologic stress, the undifferentiated cells undergo rapid proliferation to accommodate organismic need. Sufficient adrenocortical proliferative capacity lasting the lifespan of the host has been demonstrated through cell transplantation and enucleation experiments. Labeling experiments with tritium, BrdU, or trypan blue, as well as transgenic assays support the clonogenic identity and location of these undefined cells within the gland periphery. We define undifferentiated adrenocortical cells as cells devoid of steroidogenic gene expression, and differentiated cells as cells with steroidogenic capacity. In this review, we discuss historic developmental studies together with recent molecular examinations that aim to characterize such populations of cells. PMID:17240045

  5. Cell Fate Determination and the Switch from Diffuse Growth to Planar Polarity in Arabidopsis Root Epidermal Cells

    PubMed Central

    Balcerowicz, Daria; Schoenaers, Sébastjen; Vissenberg, Kris

    2015-01-01

    Plant roots fulfill important functions as they serve in water and nutrient uptake, provide anchorage of the plant body in the soil and in some species form the site of symbiotic interactions with soil-living biota. Root hairs, tubular-shaped outgrowths of specific epidermal cells, significantly increase the root’s surface area and aid in these processes. In this review we focus on the molecular mechanisms that determine the hair and non-hair cell fate of epidermal cells and that define the site on the epidermal cell where the root hair will be initiated (=planar polarity determination). In the model plant Arabidopsis, trichoblast and atrichoblast cell fate results from intra- and intercellular position-dependent signaling and from complex feedback loops that ultimately regulate GL2 expressing and non-expressing cells. When epidermal cells reach the end of the root expansion zone, root hair promoting transcription factors dictate the establishment of polarity within epidermal cells followed by the selection of the root hair initiation site at the more basal part of the trichoblast. Molecular players in the abovementioned processes as well as the role of phytohormones are discussed, and open areas for future experiments are identified. PMID:26779192

  6. Reduced salivary gland size and increased presence of epithelial progenitor cells in DLK1-deficient mice.

    PubMed

    García-Gallastegui, P; Luzuriaga, J; Aurrekoetxea, M; Baladrón, V; Ruiz-Hidalgo, M J; García-Ramírez, J J; Laborda, J; Unda, F; Ibarretxe, G

    2016-06-01

    DLK1 (PREF1, pG2, or FA1) is a transmembrane and secreted protein containing epidermal growth factor-like repeats. Dlk1 expression is abundant in many tissues during embryonic and fetal development and is believed to play an important role in the regulation of tissue differentiation and fetal growth. After birth, Dlk1 expression is abolished in most tissues but is possibly reactivated to regulate stem cell activation and responses to injury. We have recently reported that DLK1 regulates many aspects of salivary gland organogenesis. Here, we have extended our studies of the salivary gland phenotype of Dlk1 knock-out mice. We have observed that salivary glands are smaller and weigh significantly less in both Dlk1 knock-out males and females compared with gender and age-matched wild-type mice and regardless of the natural sexual dimorphism in rodent salivary glands. This reduced size correlates with a reduced capacity of Dlk1-deficient mice to secrete saliva after stimulation with pilocarpine. However, histological and ultrastructural analyses of both adult and developing salivary gland tissues have revealed no defects in Dlk1 ((-/-)) mice, indicating that genetic compensation accounts for the relatively mild salivary phenotype in these animals. Finally, despite their lack of severe anomalies, we have found that salivary glands from Dlk1-deficient mice present a higher amount of CK14-positive epithelial progenitors at various developmental stages, suggesting a role for DLK1 in the regulation of salivary epithelial stem cell balance. PMID:26711912

  7. Wdr1-mediated cell shape dynamics and cortical tension are essential for epidermal planar cell polarity

    PubMed Central

    Pasolli, H. Amalia; Chai, Sophia; Nikolova, Maria; Stokes, Nicole; Fuchs, Elaine

    2015-01-01

    During mouse development, core planar cell polarity (PCP) proteins become polarized in the epidermal plane to guide angling/morphogenesis of hair follicles. How PCP is established is poorly understood. Here, we identify a key role for Wdr1 (also known as Aip1), an F-actin-binding protein that enhances cofilin/destrin-mediated F-actin disassembly. We show that cofilin and destrin function redundantly in developing epidermis, but their combined depletion perturbs cell adhesion, cytokinesis, apicobasal polarity and PCP. Although Wdr1 depletion accentuates single-loss-of-cofilin/destrin phenotypes, alone it resembles core PCP mutations. Seeking a mechanism, we find that Wdr1 and cofilin/destrin-mediated actomyosin remodelling are essential for generating or maintaining cortical tension within the developing epidermal sheet and driving the cell shape and planar orientation changes that accompany establishment of PCP in mammalian epidermis. Our findings suggest intriguing evolutionary parallels but mechanistic modifications to the distal wing hinge-mediated mechanical forces that drive cell shape change and orient PCP in the Drosophila wing disc. PMID:25915128

  8. Stem Cells, Progenitor Cells, and Lineage Decisions in the Ovary

    PubMed Central

    Hummitzsch, Katja; Anderson, Richard A.; Wilhelm, Dagmar; Wu, Ji; Telfer, Evelyn E.; Russell, Darryl L.; Robertson, Sarah A.

    2015-01-01

    Exploring stem cells in the mammalian ovary has unleashed a Pandora's box of new insights and questions. Recent evidence supports the existence of stem cells of a number of the different cell types within the ovary. The evidence for a stem cell model producing mural granulosa cells and cumulus cells is strong, despite a limited number of reports. The recent identification of a precursor granulosa cell, the gonadal ridge epithelial-like cell, is exciting and novel. The identification of female germline (oogonial) stem cells is still very new and is currently limited to just a few species. Their origins and physiological roles, if any, are unknown, and their potential to produce oocytes and contribute to follicle formation in vivo lacks robust evidence. The precursor of thecal cells remains elusive, and more compelling data are needed. Similarly, claims of very small embryonic-like cells are also preliminary. Surface epithelial cells originating from gonadal ridge epithelial-like cells and from the mesonephric epithelium at the hilum of the ovary have also been proposed. Another important issue is the role of the stroma in guiding the formation of the ovary, ovigerous cords, follicles, and surface epithelium. Immune cells may also play key roles in developmental patterning, given their critical roles in corpora lutea formation and regression. Thus, while the cellular biology of the ovary is extremely important for its major endocrine and fertility roles, there is much still to be discovered. This review draws together the current evidence and perspectives on this topic. PMID:25541635

  9. Regulation of human endothelial progenitor cell maturation by polyurethane nanocomposites.

    PubMed

    Hung, Huey-Shan; Yang, Yi-Chun; Lin, Yu-Chun; Lin, Shinn-Zong; Kao, Wei-Chien; Hsieh, Hsien-Hsu; Chu, Mei-Yun; Fu, Ru-Huei; Hsu, Shan-hui

    2014-08-01

    The mobilization and homing of endothelial progenitor cells (EPCs) are critical to the development of an antithrombotic cardiovascular prosthesis. Polyurethane (PU) with superior elasticity may provide a mechanical environment resembling that of the natural vascular tissues. The topographical cues of PU were maximized by making nanocomposites with a small amount of gold nanoparticles (AuNPs). The nanocomposites of PU-AuNPs ("PU-Au") with a favorable response of endothelial cells were previously established. In the current study, the effect of PU and PU-Au nanocomposites on the behavior of human peripheral blood EPCs was investigated in vitro and in vivo. It was found that PU-Au promoted EPCs to become differentiated endothelial cells in vitro, confirmed by the increased expressions of CD31 and VEGF-R2 surface markers. The increased maturation of EPCs was significantly more remarkable on PU-Au, probably through the stromal derived factor 1α (SDF-1α)/CXCR4 signaling pathway. In vivo experiments showed that EPCs seeded on PU-Au coated catheters effectively reduced thrombosis by differentiation into endothelial cells. Surface endothelialization with CD31 and CD34 expression as well as intimal formation with α-SMA expression was significantly accelerated in the group receiving EPC-seeded PU-Au catheters. Moreover, the analysis of collagen deposition revealed a reduction of fibrosis in the group receiving EPC-seeded PU-Au catheters as compared to the other groups. These results suggest that EPCs engineered with a proper elastic substrate may provide unique endothelialization and antithrombogenic properties that benefit vascular tissue regeneration. PMID:24836305

  10. Cardiac Progenitor Cell Cycling Stimulated by Pim-1 Kinase

    PubMed Central

    Cottage, Christopher T.; Bailey, Brandi; Fischer, Kimberlee M.; Avitable, Daniele; Collins, Brett; Tuck, Savilla; Quijada, Pearl; Gude, Natalie; Alvarez, Roberto; Muraski, John; Sussman, Mark A.

    2011-01-01

    Rationale Cardioprotective effects of Pim-1 kinase have been previously reported but the underlying mechanistic basis may involve a combination of cellular and molecular mechanisms that remain unresolved. The elucidation of the mechanistic basis for Pim-1 mediated cardioprotection provides important insights for designing therapeutic interventional strategies to treat heart disease. Objective Effects of cardiac-specific Pim-1 kinase expression on the cardiac progenitor cell (CPC) population were examined to determine whether Pim-1 mediates beneficial effects through augmenting CPC activity. Methods and Results Transgenic mice created with cardiac-specific Pim-1 overexpression (Pim-wt) exhibit enhanced Pim-1 expression in both cardiomyocytes and CPCs, both of which show increased proliferative activity assessed using 5-bromodeoxyuridine (BrdU), Ki-67, and c-Myc relative to nontransgenic controls. However, the total number of CPCs was not increased in the Pim-wt hearts during normal postnatal growth or after infarction challenge. These results suggest that Pim-1 overexpression leads to asymmetric division resulting in maintenance of the CPC population. Localization and quantitation of cell fate determinants Numb and α-adaptin by confocal microscopy were used to assess frequency of asymmetric division in the CPC population. Polarization of Numb in mitotic phospho-histone positive cells demonstrates asymmetric division in 65% of the CPC population in hearts of Pim-wt mice versus 26% in nontransgenic hearts after infarction challenge. Similarly, Pim-wt hearts had fewer cells with uniform α-adaptin staining indicative of symmetrically dividing CPCs, with 36% of the CPCs versus 73% in nontransgenic sections. Conclusions These findings define a mechanistic basis for enhanced myocardial regeneration in transgenic mice overexpressing Pim-1 kinase. PMID:20075333

  11. Endothelial progenitor cells and asymmetric dimethylarginine after renal transplantation.

    PubMed

    Teplan, Vladimír; Mahrová, Andrea; Králová-Lesná, Ivana; Racek, Jaroslav; Valkovský, Ivo; Štollová, Milena

    2015-03-01

    Levels of the endogenous nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA) are elevated and endothelial progenitor cells (EPCs) decreased in patients undergoing renal transplantation (Tx) and may contribute to cardiovascular complications. In this study, we tested the hypothesis that elevated ADMA and decreased EPC can be positively influenced with regular physical exercise early after Tx. Blood samples for analysis of ADMA and EPC were obtained from randomly selected 64 patients after Tx who agreed to participate in a supervised aerobic exercise program for 6 months (group I). Samples were collected before the training began, 1 month after surgery (with stabilized renal function), and at 6 months after initiation. Sixty-two age, sex, human leukocyte antigens (HLA) typing, duration of previous dialysis, history of cardiovascular disease, and immunosupression regimen-matched transplant patients who did not exercise regularly were examined as controls (group II). There were no differences in ADMA levels and EPC count between both groups before the training program began. After 6 months of exercise, ADMA concentration in the group I decreased (3.50 ± 0.45 vs. 2.11 ± 0.35 μmol/L; P < .01) and was also lower comparing with group II (2.11 ± 0.23 vs. 3.25 ± 0.35 μmol/L; P < .01). In the same period, EPC cells increased from 2.085 ± 650 cells/mL versus 3.991 ± 560 cells/mL, P < .01 in group I; but in group II, changes were nonsignificant (P = .11). Blood lipids, HbA1c, insulin, and systolic blood pressure were also affected by the training program. Elevated ADMA level and decreased EPC count were significantly influenced by early regular exercise in patients after Tx. PMID:25576240

  12. Aging-associated inflammation promotes selection for adaptive oncogenic events in B cell progenitors

    PubMed Central

    Henry, Curtis J.; Casás-Selves, Matias; Kim, Jihye; Zaberezhnyy, Vadym; Aghili, Leila; Daniel, Ashley E.; Jimenez, Linda; Azam, Tania; McNamee, Eoin N.; Clambey, Eric T.; Klawitter, Jelena; Serkova, Natalie J.; Tan, Aik Choon; Dinarello, Charles A.; DeGregori, James

    2015-01-01

    The incidence of cancer is higher in the elderly; however, many of the underlying mechanisms for this association remain unexplored. Here, we have shown that B cell progenitors in old mice exhibit marked signaling, gene expression, and metabolic defects. Moreover, B cell progenitors that developed from hematopoietic stem cells (HSCs) transferred from young mice into aged animals exhibited similar fitness defects. We further demonstrated that ectopic expression of the oncogenes BCR-ABL, NRASV12, or Myc restored B cell progenitor fitness, leading to selection for oncogenically initiated cells and leukemogenesis specifically in the context of an aged hematopoietic system. Aging was associated with increased inflammation in the BM microenvironment, and induction of inflammation in young mice phenocopied aging-associated B lymphopoiesis. Conversely, a reduction of inflammation in aged mice via transgenic expression of α-1-antitrypsin or IL-37 preserved the function of B cell progenitors and prevented NRASV12-mediated oncogenesis. We conclude that chronic inflammatory microenvironments in old age lead to reductions in the fitness of B cell progenitor populations. This reduced progenitor pool fitness engenders selection for cells harboring oncogenic mutations, in part due to their ability to correct aging-associated functional defects. Thus, modulation of inflammation — a common feature of aging — has the potential to limit aging-associated oncogenesis. PMID:26551682

  13. Molecular Biomarkers of Cancer Stem/Progenitor Cells Associated with Progression, Metastases, and Treatment Resistance of Aggressive Cancers

    PubMed Central

    Mimeault, Murielle; Batra, Surinder K.

    2014-01-01

    The validation of novel diagnostic, prognostic, and predictive biomarkers and therapeutic targets in tumor cells is of critical importance for optimizing the choice and efficacy of personalized therapies. Importantly, recent advances have led to the identification of gene-expression signatures in cancer cells, including cancer stem/progenitor cells, in the primary tumors, exosomes, circulating tumor cells (CTC), and disseminated cancer cells at distant metastatic sites. The gene-expression signatures may help to improve the accuracy of diagnosis and predict the therapeutic responses and overall survival of patients with cancer. Potential biomarkers in cancer cells include stem cell–like markers [CD133, aldehyde dehydrogenase (ALDH), CD44, and CD24], growth factors, and their cognate receptors [epidermal growth factor receptor (EGFR), EGFRvIII, and HER2], molecules associated with epithelial–mesenchymal transition (EMT; vimentin, N-cadherin, snail, twist, and Zeb1), regulators of altered metabolism (phosphatidylinositol-3′ kinase/Akt/mTOR), and drug resistance (multidrug transporters and macrophage inhibitory cytokine-1). Moreover, different pluripotency-associated transcription factors (Oct3/4, Nanog, Sox2, and Myc) and microRNAs that are involved in the epigenetic reprogramming and acquisition of stem cell–like properties by cancer cells during cancer progression may also be exploited as molecular biomarkers to predict the risk of metastases, systemic treatment resistance, and disease relapse of patients with cancer. PMID:24273063

  14. Human progenitor cells isolated from the developing cortex undergo decreased neurogenesis and eventual senescence following expansion in vitro

    SciTech Connect

    Wright, Lynda S.; Prowse, Karen R.; Wallace, Kyle; Linskens, Maarten H.K.; Svendsen, Clive N. . E-mail: svendsen@waisman.wisc.edu

    2006-07-01

    Isolation of a true self-renewing stem cell from the human brain would be of great interest as a reliable source of neural tissue. Here, we report that human fetal cortical cells grown in epidermal growth factor expressed low levels of telomerase and telomeres in these cultures shortened over time leading to growth arrest after 30 weeks. Following leukemia inhibitory factor (LIF) supplementation, growth rates and telomerase expression increased. This was best demonstrated following cell cycle synchronization and staining for telomerase using immunocytochemistry. This increase in activity resulted in the maintenance of telomeres at approximately 7 kb for more than 60 weeks in vitro. However, all cultures displayed a lack of oligodendrotye production, decreases in neurogenesis over time and underwent replicative senescence associated with increased expression of p21 before 70 weeks in vitro. Thus, under our culture conditions, these cells are not stable, multipotent, telomerase expressing self-renewing stem cells. They may be more accurately described as human neural progenitor cells (hNPC) with limited lifespan and bi-potent potential (neurons/astrocytes). Interestingly, hNPC follow a course of proliferation, neuronal production and growth arrest similar to that seen during expansion and development of the human cortex, thus providing a possible model neural system. Furthermore, due to their high expansion potential and lack of tumorogenicity, these cells remain a unique and safe source of tissue for clinical transplantation.

  15. Targeting HIV latency: resting memory T cells, hematopoietic progenitor cells, and future directions

    PubMed Central

    Sebastian, Nadia T.; Collins, Kathleen L.

    2014-01-01

    Current therapy for HIV effectively suppresses viral replication and prolongs life, but the infection persists due, at least in part, to latent infection of long-lived cells. One favored strategy towards a cure targets latent virus in resting memory CD4+ T cells by stimulating viral production. However, the existence of an additional reservoir in bone marrow hematopoietic progenitor cells has been detected in some treated HIV-infected people. This review describes approaches investigators have used to reactivate latent proviral genomes in resting CD4+ T cells and hematopoietic progenitor cells. In addition, we review approaches for clearance of these reservoirs along with other important topics related to HIV eradication. PMID:25189526

  16. Establishment of epidermal cell lines derived from the skin of the Atlantic bottlenose dolphin (Tursiops truncatus).

    PubMed

    Yu, Jin; Kindy, Mark S; Ellis, Blake C; Baatz, John E; Peden-Adams, Margie; Ellingham, Tara J; Wolff, Daynna J; Fair, Patricia A; Gattoni-Celli, Sebastiano

    2005-12-01

    The Atlantic bottlenose dolphin (Tursiops truncatus), a marine mammal found off the Atlantic coast, has become the focus of considerable attention because of an increasing number of mortality events witnessed in this species over the last several years along the southeastern United States. Assessment of the impact of environmental stressors on bottlenose dolphins (BND) has been difficult because of the protected status of these marine mammals. The studies presented herein focused on establishing epidermal cell cultures and cell lines as tools for the in vitro evaluation of environmental stressors on BND skin. Epidermal cell cultures were established from skin samples obtained from Atlantic BND and subjected to karyotype analysis. These cultures were further characterized using immunohistochemical methods demonstrating expression of cytokeratins. By two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), we observed that the proteomic profile of BND skin tissue samples shared distinct similarities with that of skin-derived cultures. Epidermal cell cultures were transfected with a plasmid encoding the SV40 small t- and large T-antigens, as well as the neomycin-resistance gene. Five neomycin-resistant clones were isolated and expanded, and all of them proliferated at a faster rate than nontransfected BND epidermal cultures, which exhibited signs of senescence. Cell lysates prepared from two transfected clones were shown to express, by Western blot analysis, both SV40 tumor antigens. These experimental results are consistent with the concept that transfected clones expressing SV40 tumor antigens represent immortalized BND cell lines. Epidermal cell lines derived from Tursiops truncatus will provide a unique tool for studying key features of the interaction occurring between dolphins and the environment in which they live at their most crucial interface: the skin. PMID:16281302

  17. Mast Cells Regulate Epidermal Barrier Function and the Development of Allergic Skin Inflammation.

    PubMed

    Sehra, Sarita; Serezani, Ana P M; Ocaña, Jesus A; Travers, Jeffrey B; Kaplan, Mark H

    2016-07-01

    Atopic dermatitis is a chronic inflammatory skin disease characterized by infiltration of eosinophils, T helper cells, and mast cells. The role of mast cells in atopic dermatitis is not completely understood. To define the effects of mast cells on skin biology, we observed that mast cells regulate the homeostatic expression of epidermal differentiation complex and other skin genes. Decreased epidermal differentiation complex gene expression in mice that genetically lack mast cells (Kit(W-sh/W-sh) mice) is associated with increased uptake of protein antigens painted on the skin by dendritic cells (DCs) compared with similarly treated wild-type mice, suggesting a protective role for mast cells in exposure to nominal environmental allergens. To test this further, we crossed Kit(W-sh/W-sh) mice with signal transducer and activator of transcription 6 (i.e., Stat6) VT transgenic mice that develop spontaneous atopic dermatitis-like disease that is dependent on T helper cell 2 cytokines and is associated with high serum concentrations of IgE. We observed that Stat6VT × Kit(W-sh/W-sh) mice developed more frequent and more severe allergic skin inflammation than Stat6VT transgenic mice that had mast cells. Together, these studies suggest that mast cells regulate epidermal barrier function and have a potential protective role in the development of atopic dermatitis-like disease. PMID:27021404

  18. High Glucose Causes Human Cardiac Progenitor Cell Dysfunction by Promoting Mitochondrial Fission: Role of a GLUT1 Blocker.

    PubMed

    Choi, He Yun; Park, Ji Hye; Jang, Woong Bi; Ji, Seung Taek; Jung, Seok Yun; Kim, Da Yeon; Kang, Songhwa; Kim, Yeon Ju; Yun, Jisoo; Kim, Jae Ho; Baek, Sang Hong; Kwon, Sang-Mo

    2016-07-01

    Cardiovascular disease is the most common cause of death in diabetic patients. Hyperglycemia is the primary characteristic of diabetes and is associated with many complications. The role of hyperglycemia in the dysfunction of human cardiac progenitor cells that can regenerate damaged cardiac tissue has been investigated, but the exact mechanism underlying this association is not clear. Thus, we examined whether hyperglycemia could regulate mitochondrial dynamics and lead to cardiac progenitor cell dysfunction, and whether blocking glucose uptake could rescue this dysfunction. High glucose in cardiac progenitor cells results in reduced cell viability and decreased expression of cell cycle-related molecules, including CDK2 and cyclin E. A tube formation assay revealed that hyperglycemia led to a significant decrease in the tube-forming ability of cardiac progenitor cells. Fluorescent labeling of cardiac progenitor cell mitochondria revealed that hyperglycemia alters mitochondrial dynamics and increases expression of fission-related proteins, including Fis1 and Drp1. Moreover, we showed that specific blockage of GLUT1 improved cell viability, tube formation, and regulation of mitochondrial dynamics in cardiac progenitor cells. To our knowledge, this study is the first to demonstrate that high glucose leads to cardiac progenitor cell dysfunction through an increase in mitochondrial fission, and that a GLUT1 blocker can rescue cardiac progenitor cell dysfunction and downregulation of mitochondrial fission. Combined therapy with cardiac progenitor cells and a GLUT1 blocker may provide a novel strategy for cardiac progenitor cell therapy in cardiovascular disease patients with diabetes. PMID:27350339

  19. High Glucose Causes Human Cardiac Progenitor Cell Dysfunction by Promoting Mitochondrial Fission: Role of a GLUT1 Blocker

    PubMed Central

    Choi, He Yun; Park, Ji Hye; Jang, Woong Bi; Ji, Seung Taek; Jung, Seok Yun; Kim, Da Yeon; Kang, Songhwa; Kim, Yeon Ju; Yun, Jisoo; Kim, Jae Ho; Baek, Sang Hong; Kwon, Sang-Mo

    2016-01-01

    Cardiovascular disease is the most common cause of death in diabetic patients. Hyperglycemia is the primary characteristic of diabetes and is associated with many complications. The role of hyperglycemia in the dysfunction of human cardiac progenitor cells that can regenerate damaged cardiac tissue has been investigated, but the exact mechanism underlying this association is not clear. Thus, we examined whether hyperglycemia could regulate mitochondrial dynamics and lead to cardiac progenitor cell dysfunction, and whether blocking glucose uptake could rescue this dysfunction. High glucose in cardiac progenitor cells results in reduced cell viability and decreased expression of cell cycle-related molecules, including CDK2 and cyclin E. A tube formation assay revealed that hyperglycemia led to a significant decrease in the tube-forming ability of cardiac progenitor cells. Fluorescent labeling of cardiac progenitor cell mitochondria revealed that hyperglycemia alters mitochondrial dynamics and increases expression of fission-related proteins, including Fis1 and Drp1. Moreover, we showed that specific blockage of GLUT1 improved cell viability, tube formation, and regulation of mitochondrial dynamics in cardiac progenitor cells. To our knowledge, this study is the first to demonstrate that high glucose leads to cardiac progenitor cell dysfunction through an increase in mitochondrial fission, and that a GLUT1 blocker can rescue cardiac progenitor cell dysfunction and downregulation of mitochondrial fission. Combined therapy with cardiac progenitor cells and a GLUT1 blocker may provide a novel strategy for cardiac progenitor cell therapy in cardiovascular disease patients with diabetes. PMID:27350339

  20. Immortalization and Characterization of Lineage-restricted Neuronal Progenitor Cells Derived From the Procine Olfactory Bulb

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crucial aspects in the development of in vitro neuropathogenic disease model systems are the identification, characterization, and continuous mitotic expansion of cultured neuronal cells. To facilitate long-term cultivation, we immortalized cultured porcine olfactory neuronally restricted progenitor...

  1. Innate lymphoid cell development requires TOX-dependent generation of a common ILC progenitor

    PubMed Central

    Seehus, Corey R.; Aliahmad, Parinaz; de la Torre, Brian; Iliev, Iliyan D.; Spurka, Lindsay; Funari, Vincent A.; Kaye, Jonathan

    2015-01-01

    Diverse innate lymphoid cell (ILC) subtypes have been defined, based on effector function and transcription factor expression. ILCs derive from common lymphoid progenitors, although the transcriptional pathways leading to ILC lineage specification remain poorly characterized. Here we demonstrate that transcriptional regulator TOX is required for the in vivo differentiation of common lymphoid progenitors to ILC lineage-restricted cells. In vitro modeling demonstrates that TOX deficiency results in early defects in progenitor cell survival or expansion as well as later stage ILC differentiation. In addition, comparative transcriptome analysis of bone marrow progenitors reveals that TOX-deficient cells fail to upregulate many aspects of the ILC gene program, including Notch gene targets, implicating TOX as a key determinant of early ILC lineage specification. PMID:25915732

  2. A Theoretical Model of Jigsaw-Puzzle Pattern Formation by Plant Leaf Epidermal Cells

    PubMed Central

    Higaki, Takumi; Kutsuna, Natsumaro; Akita, Kae; Takigawa-Imamura, Hisako; Yoshimura, Kenji; Miura, Takashi

    2016-01-01

    Plant leaf epidermal cells exhibit a jigsaw puzzle–like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo. PMID:27054467

  3. A Theoretical Model of Jigsaw-Puzzle Pattern Formation by Plant Leaf Epidermal Cells.

    PubMed

    Higaki, Takumi; Kutsuna, Natsumaro; Akita, Kae; Takigawa-Imamura, Hisako; Yoshimura, Kenji; Miura, Takashi

    2016-04-01

    Plant leaf epidermal cells exhibit a jigsaw puzzle-like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo. PMID:27054467

  4. In vivo ultraviolet-exposed human epidermal cells activate T suppressor cell pathways that involve CD4+CD45RA+ suppressor-inducer T cells

    SciTech Connect

    Baadsgaard, O.; Salvo, B.; Mannie, A.; Dass, B.; Fox, D.A.; Cooper, K.D. )

    1990-11-01

    In vivo UV exposure of human epidermis abrogates the function of CD1+DR+ Langerhans cells and induces the appearance of CD1-DR+ Ag-presenting macrophages. Epidermal cells from UV-exposed skin, in contrast to epidermal cells from normal skin, potently activate autologous CD4+ T cells, and, in particular, the CD45RA+ (2H4+) (suppressor-inducer) subset. We therefore determined whether UV-exposure in humans leads to a T cell response in which suppression dominates. Autologous blood T cells were incubated with epidermal cell suspensions from in vivo UV-irradiated skin. After activation, repurified T cells were transferred in graded numbers to autologous mononuclear cells (MNC) stimulated with PWM and the resultant IgG production analyzed by ELISA. Relative to T cells activated by unirradiated control epidermal cells, T cells activated by UV-exposed epidermal cells demonstrated enhanced capacity to suppress IgG production (n = 6; p less than or equal to 0.03). Within the T cell population, CD8+ cells stimulated by UV-exposed epidermal cells could be directly activated to suppress PWM-stimulated MNC Ig production if IL-2 was provided in the reaction mixture. The suppressive activity was also transferable with purified CD4+ T cells stimulated by UV-exposed epidermal cells (n = 10; p less than or equal to 0.01), and was radiosensitive. Suppression was decreased when PWM-stimulated MNC were depleted of CD8+ T cells before mixing with CD4+ T cells activated by UV-exposed epidermal cells, suggesting indirect induction of CD8+ Ts cells contained within the responding MNC populations. Indeed, physical depletion of CD45RA+ cells resulted in total abrogation of the suppressor function contained in the CD4+ T cells. Activation of suppressor function was critically dependent on DR+ APC contained in UV-exposed epidermis.

  5. Proteins deposited in the dermis are rapidly captured and presented by epidermal Langerhans cells

    PubMed Central

    Flacher, Vincent; Tripp, Christoph H.; Stoitzner, Patrizia; Haid, Bernhard; Ebner, Susanne; Koch, Franz; Park, Chae Gyu; Steinman, Ralph M.; Idoyaga, Juliana; Romani, Nikolaus

    2010-01-01

    Antigen-presenting cells can capture antigens that are deposited in the skin, including vaccines given subcutaneously. These include different dendritic cells (DC) such as epidermal Langerhans cells (LC), dermal DC and dermal langerin+ DC. To evaluate access of dermal antigens to skin DC, we used mAb to two C-type lectin endocytic receptors, DEC-205/CD205 and langerin/CD207. When applied to murine and human skin explant cultures, these mAb were efficiently taken up by epidermal LC. Additionally, anti-DEC-205 targeted langerin+ CD103+ and langerin− CD103− mouse dermal DC. Unexpectedly, intradermal injection of either mAb, but not isotype control, resulted in strong and rapid labelling of LC in situ, implying that large molecules can diffuse through the basement membrane into the epidermis. Epidermal LC targeted in vivo by ovalbumin-coupled anti-DEC-205 potently presented antigen to CD4+ and CD8+ T cells. Thus, epidermal LC play a major role in uptake of lectin-binding ligands under standard vaccination conditions. PMID:19890348

  6. Human Mammary Luminal Epithelial Cells Contain Progenitors to Myoepithelial Cells

    SciTech Connect

    Pechoux, Christine; Gudjonsson, Thorarinn; Ronnov-Jessen, Lone; Bissell, Mina J; Petersen, Ole

    1999-02-01

    The origin of the epithelial and myoepithelial cells in the human breast has not been delineated. In this study we have addressed whether luminal epithelial cells and myoepithelial cells are vertically connected, i.e., whether one is the precursor for the other. We used a primary culture assay allowing preservation of basic phenotypic traits of luminal epithelial and myoepithelial cells in culture. The two cell types were then separated immunomagnetically using antibodies directed against lineage-specific cell surface antigens into at best 100% purity. The cellular identity was ascertained by cytochemistry, immunoblotting, and 2-D gel electrophoresis. Luminal epithelial cells were identified by strong expression of cytokeratins 18 and 19 while myoepithelial cells were recognized by expression of vimentin and {alpha}-smooth muscle actin. We used a previously devised culture medium (CDM4) that allows vigorous expansion of proliferative myoepithelial cells and also devised a medium (CDM6) that allowed sufficient expansion of differentiated luminal epithelial cells based on addition of hepatocyte growth factor/scatter factor. The two different culture media supported each lineage for at least five passages without signs of interconversion. We used parallel cultures where we switched culture media, thus testing the ability of each lineage to convert to the other. Whereas the myoepithelial lineage showed no signs of interconversion, a subset of luminal epithelial cells, gradually, but distinctly, converted to myoepithelial cells. We propose that in the mature human breast, it is the luminal epithelial cell compartment that gives rise to myoepithelial cells rather than the other way around.

  7. The progenitor cell compartment in the feline liver: an (immuno)histochemical investigation.

    PubMed

    Ijzer, J; Kisjes, J R; Penning, L C; Rothuizen, J; van den Ingh, T S G A M

    2009-07-01

    The hepatic progenitor compartment is of vital importance in liver regeneration when hepatocellular replication is impaired, as it occurs in acute fulminant hepatitis or severe liver fibrosis. It consists of resident progenitor cells in the normal liver, and ductular reaction and intermediate hepatobiliary cells in diseased livers. An histologic and immunohistochemical study was conducted to demonstrate putative hepatic progenitor cells in the normal liver (n = 5) and in a range of hepatic diseases (n = 13) in the cat. Formalin-fixed, paraffin-embedded specimens were stained with HE, the van Gieson stain, and the reticulin stain according to Gordon and Sweet, and immunohistochemically stained for cytokeratin-7 (CK7), human hepatocyte marker 1 (Hepar1), and multidrug resistance-binding protein-2/ATP binding cassette C2 (MRP2). The normal feline liver contains a liver progenitor cell morphologically similar to humans and dogs, which resides in the canal of Hering. In acute and chronic feline liver diseases a ductular reaction is present, whether in the parenchyma or in a portal or septal location. The putative progenitor cells could easily be demonstrated by staining for CK7, whereas they were generally negative for Hepar1 and MRP2. In a parenchymal ductular reaction mitotic figures and cells with an intermediate hepatobiliary phenotype could be demonstrated. This is the first account of hepatic progenitor cells in feline liver. PMID:19329493

  8. Endothelial Progenitor Cells in Diabetic Microvascular Complications: Friends or Foes?

    PubMed Central

    Yu, Cai-Guo; Zhang, Ning; Yuan, Sha-Sha; Ma, Yan; Yang, Long-Yan; Feng, Ying-Mei; Zhao, Dong

    2016-01-01

    Despite being featured as metabolic disorder, diabetic patients are largely affected by hyperglycemia-induced vascular abnormality. Accumulated evidence has confirmed the beneficial effect of endothelial progenitor cells (EPCs) in coronary heart disease. However, antivascular endothelial growth factor (anti-VEGF) treatment is the main therapy for diabetic retinopathy and nephropathy, indicating the uncertain role of EPCs in the pathogenesis of diabetic microvascular disease. In this review, we first illustrate how hyperglycemia induces metabolic and epigenetic changes in EPCs, which exerts deleterious impact on their number and function. We then discuss how abnormal angiogenesis develops in eyes and kidneys under diabetes condition, focusing on “VEGF uncoupling with nitric oxide” and “competitive angiopoietin 1/angiopoietin 2” mechanisms that are shared in both organs. Next, we dissect the nature of EPCs in diabetic microvascular complications. After we overview the current EPCs-related strategies, we point out new EPCs-associated options for future exploration. Ultimately, we hope that this review would uncover the mysterious nature of EPCs in diabetic microvascular disease for therapeutics. PMID:27313624

  9. Endothelial Progenitor Cells in Diabetic Microvascular Complications: Friends or Foes?

    PubMed

    Yu, Cai-Guo; Zhang, Ning; Yuan, Sha-Sha; Ma, Yan; Yang, Long-Yan; Feng, Ying-Mei; Zhao, Dong

    2016-01-01

    Despite being featured as metabolic disorder, diabetic patients are largely affected by hyperglycemia-induced vascular abnormality. Accumulated evidence has confirmed the beneficial effect of endothelial progenitor cells (EPCs) in coronary heart disease. However, antivascular endothelial growth factor (anti-VEGF) treatment is the main therapy for diabetic retinopathy and nephropathy, indicating the uncertain role of EPCs in the pathogenesis of diabetic microvascular disease. In this review, we first illustrate how hyperglycemia induces metabolic and epigenetic changes in EPCs, which exerts deleterious impact on their number and function. We then discuss how abnormal angiogenesis develops in eyes and kidneys under diabetes condition, focusing on "VEGF uncoupling with nitric oxide" and "competitive angiopoietin 1/angiopoietin 2" mechanisms that are shared in both organs. Next, we dissect the nature of EPCs in diabetic microvascular complications. After we overview the current EPCs-related strategies, we point out new EPCs-associated options for future exploration. Ultimately, we hope that this review would uncover the mysterious nature of EPCs in diabetic microvascular disease for therapeutics. PMID:27313624

  10. Hyperoxia, Endothelial Progenitor Cell Mobilization, and Diabetic Wound Healing

    PubMed Central

    Liu, Zhao-Jun

    2008-01-01

    Abstract Diabetic foot disease is a major health problem, which affects 15% of the 200 million patients with diabetes worldwide. Diminished peripheral blood flow and decreased local neovascularization are critical factors that contribute to the delayed or nonhealing wounds in these patients. The correction of impaired local angiogenesis may be a key component in developing therapeutic protocols for treating chronic wounds of the lower extremity and diabetic foot ulcers. Endothelial progenitor cells (EPCs) are the key cellular effectors of postnatal neovascularization and play a central role in wound healing, but their circulating and wound-level numbers are decreased in diabetes, implicating an abnormality in EPC mobilization and homing mechanisms. The deficiency in EPC mobilization is presumably due to impairment of eNOS-NO cascade in bone marrow (BM). Hyperoxia, induced by a clinically relevant hyperbaric oxygen therapy (HBO) protocol, can significantly enhance the mobilization of EPCs from the BM into peripheral blood. However, increased circulating EPCs failed to reach to wound tissues. This is partly a result of downregulated production of SDF-1α in local wound lesions with diabetes. Administration of exogenous SDF-1α into wounds reversed the EPC homing impairment and, with hyperoxia, synergistically enhanced EPC mobilization, homing, neovascularization, and wound healing. Antioxid. Redox Signal. 10, 1869–1882. PMID:18627349

  11. Tbx16 regulates hox gene activation in mesodermal progenitor cells.

    PubMed

    Payumo, Alexander Y; McQuade, Lindsey E; Walker, Whitney J; Yamazoe, Sayumi; Chen, James K

    2016-09-01

    The transcription factor T-box 16 (Tbx16, or Spadetail) is an essential regulator of paraxial mesoderm development in zebrafish (Danio rerio). Mesodermal progenitor cells (MPCs) fail to differentiate into trunk somites in tbx16 mutants and instead accumulate within the tailbud in an immature state. However, the mechanisms by which Tbx16 controls mesoderm patterning have remained enigmatic. We describe here the use of photoactivatable morpholino oligonucleotides to determine the Tbx16 transcriptome in MPCs. We identified 124 Tbx16-regulated genes that were expressed in zebrafish gastrulae, including several developmental signaling proteins and regulators of gastrulation, myogenesis and somitogenesis. Unexpectedly, we observed that a loss of Tbx16 function precociously activated posterior hox genes in MPCs, and overexpression of a single posterior hox gene was sufficient to disrupt MPC migration. Our studies support a model in which Tbx16 regulates the timing of collinear hox gene activation to coordinate the anterior-posterior fates and positions of paraxial MPCs. PMID:27376691

  12. Ca(2+) Signalling in Endothelial Progenitor Cells: Friend or Foe?

    PubMed

    Moccia, Francesco; Guerra, Germano

    2016-02-01

    Endothelial progenitor cells (EPCs) are mobilized either from the bone marrow and/or the arterial to replace dysfunctional endothelial cells and rescue blood perfusion in ischemic tissues. In addition, they may contribute to the angiogenic switch, thereby sustaining tumour growth and metastatization. Understanding the molecular mechanisms utilized by vascular endothelial growth factor (VEGF) to stimulate EPCs might unveil novel targets to enhance their clinical outcome in regenerative medicine and to adverse tumour vascularisation. VEGF stimulates peripheral blood-derived EPCs to undergo repetitive Ca(2+) oscillations shaped by the interaction between inositol-1,4,5-trisphosphate (InsP3 )-dependent Ca(2+) release and store-operated Ca(2+) entry (SOCE). However, the Ca(2+) machinery underlying VEGF-induced Ca(2+) spikes changes in umbilical cord blood-derived EPCs, which require TRPC3-mediated Ca(2+) entry to trigger the interplay between InsP3 and SOCE. Surprisingly, VEGF fails to elicit pro-angiogenic Ca(2+) signals when EPCs derive from renal cellular carcinoma patients, thus questioning the suitability of VEGFR-2 as a target for anti-angiogenic treatments in these individuals. The lack of response to VEGF is likely due to the dramatic rearrangement of the Ca(2+) toolkit occurring in RCC-derived EPCs. Finally, primary myelofibrosis-derived EPCs display a further pattern of reorganization of the Ca(2+) machinery and proliferate independently of SOCE. Thus, the Ca(2+) machinery in human ECFCs is extremely plastic and may change depending on the physio-pathological background of the donor. As a consequence, the Ca(2+) toolkit could properly be used to enhance the regenerative outcome of cell-based therapy or adverse tumor vascularisation. PMID:26247172

  13. Repurposing Treprostinil for Enhancing Hematopoietic Progenitor Cell Transplantation

    PubMed Central

    Kazemi, Zahra; Bergmayr, Christian; Prchal-Murphy, Michaela; Javaheri, Tahereh; Themanns, Madeleine; Pham, Ha T. T.; Strohmaier, Wolfgang; Sexl, Veronika; Zebedin-Brandl, Eva

    2016-01-01

    Activation of Gs-coupled receptors enhances engraftment of hematopoietic stem and progenitor cells (HSPCs). We tested the hypothesis that treprostinil, a prostacyclin analog approved for the treatment of pulmonary hypertension, can be repurposed to improve hematopoietic stem cell transplantation. Murine and human HSPCs were isolated from bone marrow and umbilical cord blood, respectively. Prostanoid receptor agonists and the combination thereof with forskolin were tested for their capacity to stimulate [3H]cAMP accumulation in HSPCs. Three independent approaches were employed to verify the ability of agonist-activated HSPCs to reconstitute the bone marrow in lethally irradiated recipient mice. The underlying mechanism was explored in cellular migration assays and by blocking C-X-C motif chemokine receptor 4 (CXCR4). Among several prostanoid agonists tested in combination with forskolin, treprostinil was most efficacious in raising intracellular cAMP levels in murine and human HPSCs. Injection of murine and human HSPCs, which had been pretreated with treprostinil and forskolin, enhanced survival of lethally irradiated recipient mice. Survival was further improved if recipient mice were subcutaneously administered treprostinil (0.15 mg kg−1 8 h−1) for 10 days. This regimen also reduced the number of HSPCs required to rescue lethally irradiated mice. Enhanced survival of recipient mice was causally related to treprostinil-enhanced CXCR4-dependent migration of HSPCs. Treprostinil stimulates the engraftment of human and murine hematopoietic stem cells without impairing their capacity for self-renewal. The investigated dose range corresponds to the dose approved for human use. Hence, these findings may be readily translated into a clinical application. PMID:26989084

  14. Repurposing Treprostinil for Enhancing Hematopoietic Progenitor Cell Transplantation.

    PubMed

    Kazemi, Zahra; Bergmayr, Christian; Prchal-Murphy, Michaela; Javaheri, Tahereh; Themanns, Madeleine; Pham, Ha T T; Strohmaier, Wolfgang; Sexl, Veronika; Freissmuth, Michael; Zebedin-Brandl, Eva

    2016-06-01

    Activation of Gs-coupled receptors enhances engraftment of hematopoietic stem and progenitor cells (HSPCs). We tested the hypothesis that treprostinil, a prostacyclin analog approved for the treatment of pulmonary hypertension, can be repurposed to improve hematopoietic stem cell transplantation. Murine and human HSPCs were isolated from bone marrow and umbilical cord blood, respectively. Prostanoid receptor agonists and the combination thereof with forskolin were tested for their capacity to stimulate [(3)H]cAMP accumulation in HSPCs. Three independent approaches were employed to verify the ability of agonist-activated HSPCs to reconstitute the bone marrow in lethally irradiated recipient mice. The underlying mechanism was explored in cellular migration assays and by blocking C-X-C motif chemokine receptor 4 (CXCR4). Among several prostanoid agonists tested in combination with forskolin, treprostinil was most efficacious in raising intracellular cAMP levels in murine and human HPSCs. Injection of murine and human HSPCs, which had been pretreated with treprostinil and forskolin, enhanced survival of lethally irradiated recipient mice. Survival was further improved if recipient mice were subcutaneously administered treprostinil (0.15 mg kg(-1) 8 h(-1)) for 10 days. This regimen also reduced the number of HSPCs required to rescue lethally irradiated mice. Enhanced survival of recipient mice was causally related to treprostinil-enhanced CXCR4-dependent migration of HSPCs. Treprostinil stimulates the engraftment of human and murine hematopoietic stem cells without impairing their capacity for self-renewal. The investigated dose range corresponds to the dose approved for human use. Hence, these findings may be readily translated into a clinical application. PMID:26989084

  15. Use of spleen organ cultures to monitor hemopoietic progenitor cell regeneration following irradiation and marrow transplantation

    SciTech Connect

    von Melchner, H.; Metcalf, D.; Mandel, T.E.

    1980-11-01

    After lethal irradiation of C57BL mice followed by the injection of 10/sup 7/ marrow cells, total cellularity and progenitor cell levels exceeded pretreatment levels within 12 days in the spleen, but regeneration remained incomplete in the marrow. The exceptional regenerative capacity of progenitor populations in the spleen was observed in organ cultures of spleen slices prepared 24 h after irradiation and transplantation, excluding continuous repopulation from the marrow as a significant factor in splenic regeneration.

  16. Boron neutron capture therapy induces cell cycle arrest and cell apoptosis of glioma stem/progenitor cells in vitro

    PubMed Central

    2013-01-01

    Background Glioma stem cells in the quiescent state are resistant to clinical radiation therapy. An almost inevitable glioma recurrence is due to the persistence of these cells. The high linear energy transfer associated with boron neutron capture therapy (BNCT) could kill quiescent and proliferative cells. Methods The present study aimed to evaluate the effects of BNCT on glioma stem/progenitor cells in vitro. The damage induced by BNCT was assessed using cell cycle progression, apoptotic cell ratio and apoptosis-associated proteins expression. Results The surviving fraction and cell viability of glioma stem/progenitor cells were decreased compared with differentiated glioma cells using the same boronophenylalanine pretreatment and the same dose of neutron flux. BNCT induced cell cycle arrest in the G2/M phase and cell apoptosis via the mitochondrial pathway, with changes in the expression of associated proteins. Conclusions Glioma stem/progenitor cells, which are resistant to current clinical radiotherapy, could be effectively killed by BNCT in vitro via cell cycle arrest and apoptosis using a prolonged neutron irradiation, although radiosensitivity of glioma stem/progenitor cells was decreased compared with differentiated glioma cells when using the same dose of thermal neutron exposure and boronophenylalanine pretreatment. Thus, BNCT could offer an appreciable therapeutic advantage to prevent tumor recurrence, and may become a promising treatment in recurrent glioma. PMID:23915425

  17. Motor neurons and oligodendrocytes arise from distinct cell lineages by progenitor recruitment

    PubMed Central

    Ravanelli, Andrew M.; Appel, Bruce

    2015-01-01

    During spinal cord development, ventral neural progenitor cells that express the transcription factors Olig1 and Olig2, called pMN progenitors, produce motor neurons and then oligodendrocytes. Whether motor neurons and oligodendrocytes arise from common or distinct progenitors in vivo is not known. Using zebrafish, we found that motor neurons and oligodendrocytes are produced sequentially by distinct progenitors that have distinct origins. When olig2+ cells were tracked during the peak period of motor neuron formation, most differentiated as motor neurons without further cell division. Using time-lapse imaging, we found that, as motor neurons differentiated, more dorsally positioned neuroepithelial progenitors descended to the pMN domain and initiated olig2 expression. Inhibition of Hedgehog signaling during motor neuron differentiation blocked the ventral movement of progenitors, the progressive initiation of olig2 expression, and oligodendrocyte formation. We therefore propose that the motor neuron-to-oligodendrocyte switch results from Hedgehog-mediated recruitment of glial-fated progenitors to the pMN domain subsequent to neurogenesis. PMID:26584621

  18. Identification of Candidate Transcriptional Regulators of Epidermal Transfer Cell Development in Vicia faba Cotyledons

    PubMed Central

    Arun-Chinnappa, Kiruba S.; McCurdy, David W.

    2016-01-01

    Transfer cells (TCs) are anatomically-specialized cells formed at apoplasmic-symplasmic bottlenecks in nutrient transport pathways in plants. TCs form invaginated wall ingrowths which provide a scaffold to amplify plasma membrane surface area and thus increase the density of nutrient transporters required to achieve enhanced nutrient flow across these bottlenecks. Despite their importance to nutrient transport in plants, little is known of the transcriptional regulation of wall ingrowth formation. Here, we used RNA-Seq to identify transcription factors putatively involved in regulating epidermal TC development in cotyledons of Vicia faba. Comparing cotyledons cultured for 0, 3, 9, and 24 h to induce trans-differentiation of epidermal TCs identified 43 transcription factors that showed either epidermal-specific or epidermal–enhanced expression, and 10 that showed epidermal-specific down regulation. Members of the WRKY and ethylene-responsive families were prominent in the cohort of transcription factors showing epidermal-specific or epidermal–enhanced expression, consistent with the initiation of TC development often representing a response to stress. Members of the MYB family were also prominent in these categories, including orthologs of MYB genes involved in localized secondary wall deposition in Arabidopsis thaliana. Among the group of transcription factors showing down regulation were various homeobox genes and members of the MADs-box and zinc-finger families of poorly defined functions. Collectively, this study identified several transcription factors showing expression characteristics and orthologous functions that indicate likely participation in transcriptional regulation of epidermal TC development in V. faba cotyledons. PMID:27252730

  19. Functional Kidney Bioengineering with Pluripotent Stem-Cell-Derived Renal Progenitor Cells and Decellularized Kidney Scaffolds.

    PubMed

    Du, Chan; Narayanan, Karthikeyan; Leong, Meng Fatt; Ibrahim, Mohammed Shahrudin; Chua, Ying Ping; Khoo, Vanessa Mei Hui; Wan, Andrew C A

    2016-08-01

    Recent advances in developmental biology and stem cell technology have led to the engineering of functional organs in a dish. However, the limited size of these organoids and absence of a large circulatory system poses limits to its clinical translation. To overcome these issues, decellularized whole kidney scaffolds with native microstructure and extracellular matrix (ECM) are employed for kidney bioengineering, using human-induced pluripotent-stem-cell-derived renal progenitor cells and endothelial cells. To demonstrate ECM-guided cellular assembly, the present work is focused on generating the functional unit of the kidney, the glomerulus. In the repopulated organ, the presence of endothelial cells broadly upregulates the expression level of genes related to renal development. When the cellularized native scaffolds are implanted in SCID mice, glomeruli assembly can be achieved by co-culture of the renal progenitors and endothelial cells. These individual glomerular units are shown to be functional in the context of the whole organ using a simulated bio-reactor set-up with urea and creatinine excretion and albumin reabsorption. Our results indicate that the repopulation of decellularized native kidney using clinically relevant, expandable patient-specific renal progenitors and endothelial cells may be a viable approach for the generation of a functional whole kidney. PMID:27294565

  20. Induced Pluripotent Stem Cell-Derived Cardiac Progenitors Differentiate to Cardiomyocytes and Form Biosynthetic Tissues

    PubMed Central

    Chakraborty, Syandan; Chellapan, Malathi; Bursac, Nenad; Leong, Kam W.

    2013-01-01

    The mammalian heart has little capacity to regenerate, and following injury the myocardium is replaced by non-contractile scar tissue. Consequently, increased wall stress and workload on the remaining myocardium leads to chamber dilation, dysfunction, and heart failure. Cell-based therapy with an autologous, epigenetically reprogrammed, and cardiac-committed progenitor cell source could potentially reverse this process by replacing the damaged myocardium with functional tissue. However, it is unclear whether cardiac progenitor cell-derived cardiomyocytes are capable of attaining levels of structural and functional maturity comparable to that of terminally-fated cardiomyocytes. Here, we first describe the derivation of mouse induced pluripotent stem (iPS) cells, which once differentiated allow for the enrichment of Nkx2-5(+) cardiac progenitors, and the cardiomyocyte-specific expression of the red fluorescent protein. We show that the cardiac progenitors are multipotent and capable of differentiating into endothelial cells, smooth muscle cells and cardiomyocytes. Moreover, cardiac progenitor selection corresponds to cKit(+) cell enrichment, while cardiomyocyte cell-lineage commitment is concomitant with dual expression of either cKit/Flk1 or cKit/Sca-1. We proceed to show that the cardiac progenitor-derived cardiomyocytes are capable of forming electrically and mechanically coupled large-scale 2D cell cultures with mature electrophysiological properties. Finally, we examine the cell progenitors’ ability to form electromechanically coherent macroscopic tissues, using a physiologically relevant 3D culture model and demonstrate that following long-term culture the cardiomyocytes align, and form robust electromechanical connections throughout the volume of the biosynthetic tissue construct. We conclude that the iPS cell-derived cardiac progenitors are a robust cell source for tissue engineering applications and a 3D culture platform for pharmacological screening and

  1. Human Breast Progenitor Cell Numbers Are Regulated by WNT and TBX3

    PubMed Central

    Arendt, Lisa M.; St. Laurent, Jessica; Wronski, Ania; Caballero, Silvia; Lyle, Stephen R.; Naber, Stephen P.; Kuperwasser, Charlotte

    2014-01-01

    Background Although human breast development is mediated by hormonal and non-hormonal means, the mechanisms that regulate breast progenitor cell activity remain to be clarified. This limited understanding of breast progenitor cells has been due in part to the lack of appropriate model systems to detect and characterize their properties. Methods To examine the effects of WNT signaling and TBX3 expression on progenitor activity in the breast, primary human mammary epithelial cells (MEC) were isolated from reduction mammoplasty tissues and transduced with lentivirus to overexpress WNT1 or TBX3 or reduce expression of their cognate receptors using shRNA. Changes in progenitor activity were quantified using characterized assays. We identified WNT family members expressed by cell populations within the epithelium and assessed alterations in expression of WNT family ligands by MECs in response to TBX3 overexpression and treatment with estrogen and progesterone. Results Growth of MECs on collagen gels resulted in the formation of distinct luminal acinar and basal ductal colonies. Overexpression of TBX3 in MECs resulted in increased ductal colonies, while shTBX3 expression diminished both colony types. Increased WNT1 expression led to enhanced acinar colony formation, shLRP6 decreased both types of colonies. Estrogen stimulated the formation of acinar colonies in control MEC, but not shLRP6 MEC. Formation of ductal colonies was enhanced in response to progesterone. However, while shLRP6 decreased MEC responsiveness to progesterone, shTBX3 expression did not alter this response. Conclusions We identified two phenotypically distinguishable lineage-committed progenitor cells that contribute to different structural elements and are regulated via hormonal and non-hormonal mechanisms. WNT signaling regulates both types of progenitor activity. Progesterone favors the expansion of ductal progenitor cells, while estrogen stimulates the expansion of acinar progenitor cells. Paracrine

  2. Circulating Progenitor Cells and Vascular Dysfunction in Chronic Obstructive Pulmonary Disease

    PubMed Central

    Pizarro, Sandra; García-Lucio, Jéssica; Peinado, Víctor I.; Tura-Ceide, Olga; Díez, Marta; Blanco, Isabel; Sitges, Marta; Petriz, Jordi; Torralba, Yolanda; Marín, Pedro; Roca, Josep; Barberà, Joan Albert

    2014-01-01

    Background In chronic obstructive pulmonary disease (COPD), decreased progenitor cells and impairment of systemic vascular function have been suggested to confer higher cardiovascular risk. The origin of these changes and their relationship with alterations in the pulmonary circulation are unknown. Objectives To investigate whether changes in the number of circulating hematopoietic progenitor cells are associated with pulmonary hypertension or changes in endothelial function. Methods 62 COPD patients and 35 controls (18 non-smokers and 17 smokers) without cardiovascular risk factors other than cigarette smoking were studied. The number of circulating progenitors was measured as CD45+CD34+CD133+ labeled cells by flow cytometry. Endothelial function was assessed by flow-mediated dilation. Markers of inflammation and angiogenesis were also measured in all subjects. Results Compared with controls, the number of circulating progenitor cells was reduced in COPD patients. Progenitor cells did not differ between control smokers and non-smokers. COPD patients with pulmonary hypertension showed greater number of progenitor cells than those without pulmonary hypertension. Systemic endothelial function was worse in both control smokers and COPD patients. Interleukin-6, fibrinogen, high sensitivity C-reactive protein, vascular endothelial growth factor and tumor necrosis factor were increased in COPD. In COPD patients, the number of circulating progenitor cells was inversely related to the flow-mediated dilation of systemic arteries. Conclusions Pulmonary and systemic vascular impairment in COPD is associated with cigarette smoking but not with the reduced number of circulating hematopoietic progenitors. The latter appears to be a consequence of the disease itself not related to smoking habit. PMID:25171153

  3. CD166-mediated epidermal growth factor receptor phosphorylation promotes the growth of oral squamous cell carcinoma.

    PubMed

    Jia, Guodong; Wang, Xu; Yan, Ming; Chen, Wantao; Zhang, Ping

    2016-08-01

    CD166 has been considered a relatively specific marker of stem cells and cancer stem cells, and the altered expression of CD166 has also been reported as a prognostic marker of several other types of cancer. However, the molecular functions of CD166 in these cancer cells are largely unknown. In this study, we found that CD166 significantly enhanced epidermal growth factor receptor (EGFR) phosphorylation and prolonged epidermal growth factor (EGF)/EGFR signalling activation. In addition, EGF stimulation in CD166-overexpressing oral squamous carcinoma cells led to enhanced colony formation, invasion capacity and cytoskeletal re-organization in vitro and elevated tumourigenesis in vivo. Taken together, the results of our study identify CD166 as an intriguing therapeutic target for patients suffering from oral squamous cell carcinoma (OSCC). PMID:27424177

  4. Molecular imaging to target transplanted muscle progenitor cells.

    PubMed

    Gutpell, Kelly; McGirr, Rebecca; Hoffman, Lisa

    2013-01-01

    Duchenne muscular dystrophy (DMD) is a severe genetic neuromuscular disorder that affects 1 in 3,500 boys, and is characterized by progressive muscle degeneration. In patients, the ability of resident muscle satellite cells (SCs) to regenerate damaged myofibers becomes increasingly inefficient. Therefore, transplantation of muscle progenitor cells (MPCs)/myoblasts from healthy subjects is a promising therapeutic approach to DMD. A major limitation to the use of stem cell therapy, however, is a lack of reliable imaging technologies for long-term monitoring of implanted cells, and for evaluating its effectiveness. Here, we describe a non-invasive, real-time approach to evaluate the success of myoblast transplantation. This method takes advantage of a unified fusion reporter gene composed of genes (firefly luciferase [fluc], monomeric red fluorescent protein [mrfp] and sr39 thymidine kinase [sr39tk]) whose expression can be imaged with different imaging modalities. A variety of imaging modalities, including positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), optical imaging, and high frequency 3D-ultrasound are now available, each with unique advantages and limitations. Bioluminescence imaging (BLI) studies, for example, have the advantage of being relatively low cost and high-throughput. It is for this reason that, in this study, we make use of the firefly luciferase (fluc) reporter gene sequence contained within the fusion gene and bioluminescence imaging (BLI) for the short-term localization of viable C2C12 myoblasts following implantation into a mouse model of DMD (muscular dystrophy on the X chromosome [mdx] mouse). Importantly, BLI provides us with a means to examine the kinetics of labeled MPCs post-implantation, and will be useful to track cells repeatedly over time and following migration. Our reporter gene approach further allows us to merge multiple imaging modalities in a single living

  5. Reduced circulating endothelial progenitor cells in reversible cerebral vasoconstriction syndrome

    PubMed Central

    2014-01-01

    Background The pathophysiology of reversible cerebral vasoconstriction syndrome (RCVS) remains elusive. Endothelial dysfunction might play a role, but direct evidence is lacking. This study aimed to explore whether patients with RCVS have a reduced level of circulating circulating endothelial progenitor cells (EPCs) to repair the dysfunctional endothelial vasomotor control. Methods We prospectively recruited 24 patients with RCVS within one month of disease onset and 24 healthy age- and sex-matched controls. Flow cytometry was used to quantify the numbers of circulating EPCs, defined as KDR+CD133+, CD34+CD133+, and CD34+KDR+ double-positive mononuclear cells. The Lindegaard index, an index of vasoconstriction, was calculated by measuring the mean flow velocity of middle cerebral arteries and distal extracranial internal carotid arteries via color-coded sonography on the same day as blood drawing. A Lindegaard index of 2 was chosen as the cutoff value for significant vasoconstriction of middle cerebral arteries based on our previous study. Results Patients with RCVS had a reduced number of CD34+KDR+ cells (0.009 ± 0.006% vs. 0.014 ± 0.010%, p = 0.031) but not KDR+CD133+ cells or CD34+CD133+ EPCs, in comparison with controls. The number of CD34+KDR+ cells was inversely correlated with the Lindegaard index (rs = -0.418, p = 0.047). Of note, compared to controls, patients with a Lindegaard index > 2 (n = 13) had a reduced number of CD34+KDR+ cells (0.007 ± 0.005% vs. 0.014 ± 0.010%, p = 0.010), but those with a Lindegaard index ≤ 2 did not. Conclusions Patients with RCVS had reduced circulating CD34+KDR+ EPCs, which were correlated with the severity of vasoconstriction. Endothelial dysfunction might contribute to the pathogenesis of RCVS. PMID:25466718

  6. Epidermal Cells Expressing Putative Cell Markers in Nonglabrous Skin Existing in Direct Proximity with the Distal End of the Arrector Pili Muscle

    PubMed Central

    Rufaut, N. W.; Jones, L.; Sinclair, R.

    2016-01-01

    Inconsistent with the view that epidermal stem cells reside randomly spread along the basal layer of the epidermal rete ridges, we found that epidermal cells expressing stem cell markers in nonglabrous skin exist in direct connection with the distal end of the arrector pili muscle. The epidermal cells that express stem cell markers consist of a subpopulation of basal keratinocytes located in a niche at the lowermost portion of the rete ridges at the distal arrector pili muscle attachment site. Keratinocytes in the epidermal stem cell niche express K15, MCSP, and α6 integrin. α5 integrin marks the distal end of the APM colocalized with basal keratinocytes expressing stem cell markers located in a well-protected and nourished environment at the lowermost point of the epidermis; these cells are hypothesized to participate directly in epidermal renewal and homeostasis and also indirectly in wound healing through communication with the hair follicle bulge epithelial stem cell population through the APM. Our findings, plus a reevaluation of the literature, support the hierarchical model of interfollicular epidermal stem cell units of Fitzpatrick. This new view provides insights into epidermal control and the possible involvement of epidermal stem cells in nonmelanoma skin carcinogenesis. PMID:27375744

  7. Epidermal stem cells: markers, patterning and the control of stem cell fate.

    PubMed Central

    Watt, F M

    1998-01-01

    Within the epidermis, proliferation takes place in the basal layer of keratinocytes that are attached to an underlying basement membrane. Cells that leave the basal layer undergo terminal differentiation as they move towards the tissue surface. The basal layer contains two types of proliferative keratinocyte: stem cells, which have unlimited self-renewal capacity, and transit amplifying cells, those daughters of stem cells that are destined to withdraw from the cell cycle and terminally differentiate after a few rounds of division. Stem cells express higher levels of the beta 1-integrin family of extracellular matrix receptors than transit amplifying cells and this can be used to isolate each subpopulation of keratinocyte and to determine its location within the epidermis. Variation in the levels of E-cadherin, beta-catenin and plakoglobin within the basal layer suggests that stem cells may also differ from transit amplifying cells in intercellular adhesiveness. Stem cells have a patterned distribution within the epidermal basal layer and patterning is subject to autoregulation. Constitutive expression of the transcription factor c-Myc promotes terminal differentiation by driving keratinocytes from the stem cell compartment into the transit amplifying compartment. PMID:9684280

  8. Effects of Telomerase and Telomere Length on Epidermal Stem Cell Behavior

    NASA Astrophysics Data System (ADS)

    Flores, Ignacio; Cayuela, María L.; Blasco, María A.

    2005-08-01

    A key process in organ homeostasis is the mobilization of stem cells out of their niches. We show through analysis of mouse models that telomere length, as well as the catalytic component of telomerase, Tert, are critical determinants in the mobilization of epidermal stem cells. Telomere shortening inhibited mobilization of stem cells out of their niche, impaired hair growth, and resulted in suppression of stem cell proliferative capacity in vitro. In contrast, Tert overexpression in the absence of changes in telomere length promoted stem cell mobilization, hair growth, and stem cell proliferation in vitro. The effects of telomeres and telomerase on stem cell biology anticipate their role in cancer and aging.

  9. Characterization of TLX Expression in Neural Stem Cells and Progenitor Cells in Adult Brains

    PubMed Central

    Li, Shengxiu; Sun, Guoqiang; Murai, Kiyohito; Ye, Peng; Shi, Yanhong

    2012-01-01

    TLX has been shown to play an important role in regulating the self-renewal and proliferation of neural stem cells in adult brains. However, the cellular distribution of endogenous TLX protein in adult brains remains to be elucidated. In this study, we used immunostaining with a TLX-specific antibody to show that TLX is expressed in both neural stem cells and transit-amplifying neural progenitor cells in the subventricular zone (SVZ) of adult mouse brains. Then, using a double thymidine analog labeling approach, we showed that almost all of the self-renewing neural stem cells expressed TLX. Interestingly, most of the TLX-positive cells in the SVZ represented the thymidine analog-negative, relatively quiescent neural stem cell population. Using cell type markers and short-term BrdU labeling, we demonstrated that TLX was also expressed in the Mash1+ rapidly dividing type C cells. Furthermore, loss of TLX expression dramatically reduced BrdU label-retaining neural stem cells and the actively dividing neural progenitor cells in the SVZ, but substantially increased GFAP staining and extended GFAP processes. These results suggest that TLX is essential to maintain the self-renewing neural stem cells in the SVZ and that the GFAP+ cells in the SVZ lose neural stem cell property upon loss of TLX expression.Understanding the cellular distribution of TLX and its function in specific cell types may provide insights into the development of therapeutic tools for neurodegenerative diseases by targeting TLX in neural stem/progenitors cells. PMID:22952666

  10. Transplantation of neural progenitor cells in chronic spinal cord injury.

    PubMed

    Jin, Y; Bouyer, J; Shumsky, J S; Haas, C; Fischer, I

    2016-04-21

    Previous studies demonstrated that neural progenitor cells (NPCs) transplanted into a subacute contusion injury improve motor, sensory, and bladder function. In this study we tested whether transplanted NPCs can also improve functional recovery after chronic spinal cord injury (SCI) alone or in combination with the reduction of glial scar and neurotrophic support. Adult rats received a T10 moderate contusion. Thirteen weeks after the injury they were divided into four groups and received either: 1. Medium (control), 2. NPC transplants, 3. NPC+lentivirus vector expressing chondroitinase, or 4. NPC+lentivirus vectors expressing chondroitinase and neurotrophic factors. During the 8weeks post-transplantation the animals were tested for functional recovery and eventually analyzed by anatomical and immunohistochemical assays. The behavioral tests for motor and sensory function were performed before and after injury, and weekly after transplantation, with some animals also tested for bladder function at the end of the experiment. Transplant survival in the chronic injury model was variable and showed NPCs at the injury site in 60% of the animals in all transplantation groups. The NPC transplants comprised less than 40% of the injury site, without significant anatomical or histological differences among the groups. All groups also showed similar patterns of functional deficits and recovery in the 12weeks after injury and in the 8weeks after transplantation using the Basso, Beattie, and Bresnahan rating score, the grid test, and the Von Frey test for mechanical allodynia. A notable exception was group 4 (NPC together with chondroitinase and neurotrophins), which showed a significant improvement in bladder function. This study underscores the therapeutic challenges facing transplantation strategies in a chronic SCI in which even the inclusion of treatments designed to reduce scarring and increase neurotrophic support produce only modest functional improvements. Further

  11. Directed Endothelial Progenitor Differentiation from Human Pluripotent Stem Cells Via Wnt Activation Under Defined Conditions.

    PubMed

    Bao, Xiaoping; Lian, Xiaojun; Palecek, Sean P

    2016-01-01

    Efficient derivation of endothelial cells and their progenitors from human pluripotent stem cells (hPSCs) can facilitate studies of human vascular development, disease modeling, drug discovery, and cell-based therapy. Here we provide a detailed protocol for directing hPSCs to functional endothelial cells and their progenitors in a completely defined, growth factor- and serum-free system by temporal modulation of Wnt/β-catenin signaling via small molecules. We demonstrate a 10-day, two-stage process that recapitulates endothelial cell development, in which hPSCs first differentiate to endothelial progenitors that then generate functional endothelial cells and smooth muscle cells. Methods to characterize endothelial cell identity and function are also described. PMID:27590162

  12. Cell-cycle-independent transitions in temporal identity of mammalian neural progenitor cells

    PubMed Central

    Okamoto, Mayumi; Miyata, Takaki; Konno, Daijiro; Ueda, Hiroki R.; Kasukawa, Takeya; Hashimoto, Mitsuhiro; Matsuzaki, Fumio; Kawaguchi, Ayano

    2016-01-01

    During cerebral development, many types of neurons are sequentially generated by self-renewing progenitor cells called apical progenitors (APs). Temporal changes in AP identity are thought to be responsible for neuronal diversity; however, the mechanisms underlying such changes remain largely unknown. Here we perform single-cell transcriptome analysis of individual progenitors at different developmental stages, and identify a subset of genes whose expression changes over time but is independent of differentiation status. Surprisingly, the pattern of changes in the expression of such temporal-axis genes in APs is unaffected by cell-cycle arrest. Consistent with this, transient cell-cycle arrest of APs in vivo does not prevent descendant neurons from acquiring their correct laminar fates. Analysis of cultured APs reveals that transitions in AP gene expression are driven by both cell-intrinsic and -extrinsic mechanisms. These results suggest that the timing mechanisms controlling AP temporal identity function independently of cell-cycle progression and Notch activation mode. PMID:27094546

  13. Cell-cycle-independent transitions in temporal identity of mammalian neural progenitor cells.

    PubMed

    Okamoto, Mayumi; Miyata, Takaki; Konno, Daijiro; Ueda, Hiroki R; Kasukawa, Takeya; Hashimoto, Mitsuhiro; Matsuzaki, Fumio; Kawaguchi, Ayano

    2016-01-01

    During cerebral development, many types of neurons are sequentially generated by self-renewing progenitor cells called apical progenitors (APs). Temporal changes in AP identity are thought to be responsible for neuronal diversity; however, the mechanisms underlying such changes remain largely unknown. Here we perform single-cell transcriptome analysis of individual progenitors at different developmental stages, and identify a subset of genes whose expression changes over time but is independent of differentiation status. Surprisingly, the pattern of changes in the expression of such temporal-axis genes in APs is unaffected by cell-cycle arrest. Consistent with this, transient cell-cycle arrest of APs in vivo does not prevent descendant neurons from acquiring their correct laminar fates. Analysis of cultured APs reveals that transitions in AP gene expression are driven by both cell-intrinsic and -extrinsic mechanisms. These results suggest that the timing mechanisms controlling AP temporal identity function independently of cell-cycle progression and Notch activation mode. PMID:27094546

  14. Ex Vivo and In Vivo Lentivirus-Mediated Transduction of Airway Epithelial Progenitor Cells.

    PubMed

    Leoni, Giulia; Wasowicz, Marguerite Y; Chan, Mario; Meng, Cuixiang; Farley, Raymond; Brody, Steven L; Inoue, Makoto; Hasegawa, Mamoru; Alton, Eric W F W; Griesenbach, Uta

    2015-01-01

    A key challenge in pulmonary gene therapy for cystic fibrosis is to provide long-term correction of the genetic defect. This may be achievable by targeting airway epithelial stem/progenitor cells with an integrating vector. Here, we evaluated the ability of a lentiviral vector, derived from the simian immunodeficiency virus and pseudotyped with F and HN envelope proteins from Sendai virus, to transduce progenitor basal cells of the mouse nasal airways. We first transduced basal cell-enriched cultures ex vivo and confirmed efficient transduction of cytokeratin-5 positive cells. We next asked whether progenitor cells could be transduced in vivo. We evaluated the transduction efficiency in mice pretreated by intranasal administration of polidocanol to expose the progenitor cell layer. Compared to control mice, polidocanol treated mice demonstrated a significant increase in the number of transduced basal cells at 3 and 14 days post vector administration. At 14 days, the epithelium of treated mice contained clusters (4 to 8 adjacent cells) of well differentiated ciliated, as well as basal cells suggesting a clonal expansion. These results indicate that our lentiviral vector can transduce progenitor basal cells in vivo, although transduction required denudation of the surface epithelium prior to vector administration. PMID:26471068

  15. Lineage-instructive function of C/EBPα in multipotent hematopoietic cells and early thymic progenitors.

    PubMed

    Wölfler, Albert; Danen-van Oorschot, Astrid A; Haanstra, Jurgen R; Valkhof, Marijke; Bodner, Claudia; Vroegindeweij, Eric; van Strien, Paulette; Novak, Alexandra; Cupedo, Tom; Touw, Ivo P

    2010-11-18

    Hematopoiesis is tightly controlled by transcription regulatory networks, but how and when specific transcription factors control lineage commitment are still largely unknown. Within the hematopoietic stem cell (Lin(-)Sca-1(+)c-Kit(+)) compartment these lineage-specific transcription factors are expressed at low levels but are up-regulated with the process of lineage specification. CCAAT/enhancer binding protein α (C/EBPα) represents one of these factors and is involved in myeloid development and indispensable for formation of granulocytes. To track the cellular fate of stem and progenitor cells, which express C/EBPα, we developed a mouse model expressing Cre recombinase from the Cebpa promoter and a conditional EYFP allele. We show that Cebpa/EYFP(+) cells represent a significant subset of multipotent hematopoietic progenitors, which predominantly give rise to myeloid cells in steady-state hematopoiesis. C/EBPα induced a strong myeloid gene expression signature and down-regulated E2A-induced regulators of early lymphoid development. In addition, Cebpa/EYFP(+) cells compose a fraction of early thymic progenitors with robust myeloid potential. However, Cebpa/EYFP(+) multipotent hematopoietic progenitors and early thymic progenitors retained the ability to develop into erythroid and T-lymphoid lineages, respectively. These findings support an instructive but argue against a lineage-restrictive role of C/EBPα in multipotent hematopoietic and thymic progenitors. PMID:20807890

  16. Aristaless Related Homeobox Gene, Arx, Is Implicated in Mouse Fetal Leydig Cell Differentiation Possibly through Expressing in the Progenitor Cells

    PubMed Central

    Miyabayashi, Kanako; Katoh-Fukui, Yuko; Ogawa, Hidesato; Baba, Takashi; Shima, Yuichi; Sugiyama, Noriyuki; Kitamura, Kunio; Morohashi, Ken-ichirou

    2013-01-01

    Development of the testis begins with the expression of the SRY gene in pre-Sertoli cells. Soon after, testis cords containing Sertoli and germ cells are formed and fetal Leydig cells subsequently develop in the interstitial space. Studies using knockout mice have indicated that multiple genes encoding growth factors and transcription factors are implicated in fetal Leydig cell differentiation. Previously, we demonstrated that the Arx gene is implicated in this process. However, how ARX regulates Leydig cell differentiation remained unknown. In this study, we examined Arx KO testes and revealed that fetal Leydig cell numbers largely decrease throughout the fetal life. Since our study shows that fetal Leydig cells rarely proliferate, this decrease in the KO testes is thought to be due to defects of fetal Leydig progenitor cells. In sexually indifferent fetal gonads of wild type, ARX was expressed in the coelomic epithelial cells and cells underneath the epithelium as well as cells at the gonad-mesonephros border, both of which have been described to contain progenitors of fetal Leydig cells. After testis differentiation, ARX was expressed in a large population of the interstitial cells but not in fetal Leydig cells, raising the possibility that ARX-positive cells contain fetal Leydig progenitor cells. When examining marker gene expression, we observed cells as if they were differentiating into fetal Leydig cells from the progenitor cells. Based on these results, we propose that ARX acts as a positive factor for differentiation of fetal Leydig cells through functioning at the progenitor stage. PMID:23840809

  17. Isolation of genes predominantly expressed in guard cells and epidermal cells of Nicotiana glauca.

    PubMed

    Smart, L B; Cameron, K D; Bennett, A B

    2000-04-01

    Guard cells are specialized and metabolically active cells which arise during the differentiation of the epidermis. Using Nicotiana glauca epidermal peels as a source of purified guard cells, we have constructed a cDNA library from guard cell RNA. In order to isolate genes that are predominantly expressed in guard cells, we performed a differential screen of this library, comparing the hybridization of a radiolabeled cDNA probe synthesized from guard cell RNA to that from a mesophyll cell cDNA probe. Sixteen clones were isolated based on their greater level of hybridization with the guard cell probe. Of these, eight had high homology to lipid transfer protein (LTP), two were similar to glycine-rich protein (GRP), and one displayed high homology to proline-rich proteins from Arabidopsis thaliana (AtPRP2, AtPRP4) and from potato guard cells (GPP). Northern analysis confirmed that one or more NgLTP genes, NgGRP1, and NgGPP1 are all differentially expressed, with highest levels in guard cells, and low or undetectable levels in mesophyll cells and in roots. In addition, all are induced to some degree in drought-stressed guard cells. NgLTP and NgGRP1 expression was localized by in situ hybridization to the guard cells and pavement cells in the epidermis. NgGRP1 expression was also detected in cells of the vasculature. Genomic Southern analysis indicated that LTP is encoded by a family of highly similar genes in N. glauca. This work has identified members of a subset of epidermis- and guard cell-predominant genes, whose protein products are likely to contribute to the unique properties acquired by guard cells and pavement cells during differentiation. PMID:10890533

  18. Lineage Tracing of Resident Tendon Progenitor Cells during Growth and Natural Healing

    PubMed Central

    Dyment, Nathaniel A.; Hagiwara, Yusuke; Matthews, Brya G.; Li, Yingcui; Kalajzic, Ivo; Rowe, David W.

    2014-01-01

    Unlike during embryogenesis, the identity of tissue resident progenitor cells that contribute to postnatal tendon growth and natural healing is poorly characterized. Therefore, we utilized 1) an inducible Cre driven by alpha smooth muscle actin (SMACreERT2), that identifies mesenchymal progenitors, 2) a constitutively active Cre driven by growth and differentiation factor 5 (GDF5Cre), a critical regulator of joint condensation, in combination with 3) an Ai9 Cre reporter to permanently label SMA9 and GDF5-9 populations and their progeny. In growing mice, SMA9+ cells were found in peritendinous structures and scleraxis-positive (ScxGFP+) cells within the tendon midsubstance and myotendinous junction. The progenitors within the tendon midsubstance were transiently labeled as they displayed a 4-fold expansion from day 2 to day 21 but reduced to baseline levels by day 70. SMA9+ cells were not found within tendon entheses or ligaments in the knee, suggesting a different origin. In contrast to the SMA9 population, GDF5-9+ cells extended from the bone through the enthesis and into a portion of the tendon midsubstance. GDF5-9+ cells were also found throughout the length of the ligaments, indicating a significant variation in the progenitors that contribute to tendons and ligaments. Following tendon injury, SMA9+ paratenon cells were the main contributors to the healing response. SMA9+ cells extended over the defect space at 1 week and differentiated into ScxGFP+ cells at 2 weeks, which coincided with increased collagen signal in the paratenon bridge. Thus, SMA9-labeled cells represent a unique progenitor source that contributes to the tendon midsubstance, paratenon, and myotendinous junction during growth and natural healing, while GDF5 progenitors contribute to tendon enthesis and ligament development. Understanding the mechanisms that regulate the expansion and differentiation of these progenitors may prove crucial to improving future repair strategies. PMID:24759953

  19. Development and specification of cerebellar stem and progenitor cells in zebrafish: from embryo to adult

    PubMed Central

    2013-01-01

    Background Teleost fish display widespread post-embryonic neurogenesis originating from many different proliferative niches that are distributed along the brain axis. During the development of the central nervous system (CNS) different cell types are produced in a strict temporal order from increasingly committed progenitors. However, it is not known whether diverse neural stem and progenitor cell types with restricted potential or stem cells with broad potential are maintained in the teleost fish brain. Results To study the diversity and output of neural stem and progenitor cell populations in the zebrafish brain the cerebellum was used as a model brain region, because of its well-known architecture and development. Transgenic zebrafish lines, in vivo imaging and molecular markers were used to follow and quantify how the proliferative activity and output of cerebellar progenitor populations progress. This analysis revealed that the proliferative activity and progenitor marker expression declines in juvenile zebrafish before they reach sexual maturity. Furthermore, this correlated with the diminished repertoire of cell types produced in the adult. The stem and progenitor cells derived from the upper rhombic lip were maintained into adulthood and they actively produced granule cells. Ventricular zone derived progenitor cells were largely quiescent in the adult cerebellum and produced a very limited number of glia and inhibitory inter-neurons. No Purkinje or Eurydendroid cells were produced in fish older than 3 months. This suggests that cerebellar cell types are produced in a strict temporal order from distinct pools of increasingly committed stem and progenitor cells. Conclusions Our results in the zebrafish cerebellum show that neural stem and progenitor cell types are specified and they produce distinct cell lineages and sub-types of brain cells. We propose that only specific subtypes of brain cells are continuously produced throughout life in the teleost fish

  20. Transient Expression of P-type ATPases in Tobacco Epidermal Cells.

    PubMed

    Poulsen, Lisbeth R; Palmgren, Michael G; López-Marqués, Rosa L

    2016-01-01

    Transient expression in tobacco cells is a convenient method for several purposes such as analysis of protein-protein interactions and the subcellular localization of plant proteins. A suspension of Agrobacterium tumefaciens cells carrying the plasmid of interest is injected into the intracellular space between leaf epidermal cells, which results in DNA transfer from the bacteria to the plant and expression of the corresponding proteins. By injecting mixes of Agrobacterium strains, this system offers the possibility to co-express a number of target proteins simultaneously, thus allowing for example protein-protein interaction studies. In this chapter, we describe the procedure to transiently express P-type ATPases in tobacco epidermal cells, with focus on subcellular localization of the protein complexes formed by P4-ATPases and their β-subunits. PMID:26695049

  1. Three-dimensional culture of epidermal cells on ordered cellulose scaffolds.

    PubMed

    Seyama, Tomoko; Suh, Eun Young; Kondo, Tetsuo

    2013-06-01

    An ordered cellulose film scaffold, termed a nematic ordered cellulose (NOC) template, had unique surface properties and successfully induced the establishment of a three-dimensional (3D), hierarchical structure of epidermal cells by cell attachment and subsequent culture. Initially, the scaffold surface properties were characterized through contact angle measurements and atomic force microscopy to evaluate appropriate hydrophobicity and orientation of molecular chains for 3D culture. The template surfaces exhibited higher hydrophobicity, in the range of 70-75°, than usual cellulose films and appeared suitable for surface cell adhesion. In fact, epidermal cells successfully attached and proliferated favorably on the NOC templates, similar to development in normal culture flasks. Furthermore, the NOC film, as a semipermeable template, was also employed to allow 3D proliferation of epidermal cell layers in the perpendicular direction. The template proved to be suitable as a 3D cell culture device, resulting in the proposal that the construction processes of these 3D cell layers followed the basic concept of skin formation. PMID:23624420

  2. Colorimetric growth assay for epidermal cell cultures by their crystal violet binding capacity.

    PubMed

    Bonnekoh, B; Wevers, A; Jugert, F; Merk, H; Mahrle, G

    1989-01-01

    The application of a simple, rapid, and inexpensive colorimetric growth assay was tested for human epidermal cells subcultured in uncoated plastic dishes. Cell layers were incubated with a crystal violet (CV) solution (0.2% with ethanol 2% in 0.5 M Tris-Cl buffer, pH 7.8) for 10 min at room temperature. After rinsing with 0.5 M Tris-Cl (pH 7.8) the cell layer was dried and decolorized with a sodium-dodecylsulfate solution (0.5% with ethanol 50% in 0.5 M Tris-Cl, pH 7.8) for 60 min at 37 degrees C. The extinction of the supernatant was read at the absorption maximum of 586 nm. The protein content of attached cells as classical parameter for quantifying cell growth was strongly related to CV extinction with a correlation coefficient of r = 0.98. Furthermore, the subcellular protein binding qualities of CV were analyzed. The water-soluble protein fraction of cultured epidermal cells was separated by sodium-dodecylsulfate polyacrylamide gel electrophoresis and stained with CV. We found a staining pattern which was qualitatively very similar to that of Coomassie blue, however less intense. Keratin electrophoresis revealed an affinity of CV to the 48, 50, and 56 kD cytokeratins. In conclusion, this CV assay is a reliable and simple method for the monitoring of epidermal cell growth in cultures. PMID:2482013

  3. Substrate elasticity provides mechanical signals for the expansion of hemopoietic stem and progenitor cells.

    PubMed

    Holst, Jeff; Watson, Sarah; Lord, Megan S; Eamegdool, Steven S; Bax, Daniel V; Nivison-Smith, Lisa B; Kondyurin, Alexey; Ma, Liang; Oberhauser, Andres F; Weiss, Anthony S; Rasko, John E J

    2010-10-01

    Surprisingly little is known about the effects of the physical microenvironment on hemopoietic stem and progenitor cells. To explore the physical effects of matrix elasticity on well-characterized primitive hemopoietic cells, we made use of a uniquely elastic biomaterial, tropoelastin. Culturing mouse or human hemopoietic cells on a tropoelastin substrate led to a two- to threefold expansion of undifferentiated cells, including progenitors and mouse stem cells. Treatment with cytokines in the presence of tropoelastin had an additive effect on this expansion. These biological effects required substrate elasticity, as neither truncated nor cross-linked tropoelastin reproduced the phenomenon, and inhibition of mechanotransduction abrogated the effects. Our data suggest that substrate elasticity and tensegrity are important mechanisms influencing hemopoietic stem and progenitor cell subsets and could be exploited to facilitate cell culture. PMID:20890282

  4. Progenitor cells for regenerative medicine and consequences of ART and cloning-associated epimutations.

    PubMed

    Laprise, Shari L

    2010-06-01

    The "holy grail" of regenerative medicine is the identification of an undifferentiated progenitor cell that is pluripotent, patient specific, and ethically unambiguous. Such a progenitor cell must also be able to differentiate into functional, transplantable tissue, while avoiding the risks of immune rejection. With reports detailing aberrant genomic imprinting associated with assisted reproductive technologies (ART) and reproductive cloning, the idea that human embryonic stem cells (hESCs) derived from surplus in vitro fertilized embryos or nuclear transfer ESCs (ntESCs) harvested from cloned embryos may harbor dangerous epigenetic errors has gained attention. Various progenitor cell sources have been proposed for human therapy, from hESCs to ntESCs, and from adult stem cells to induced pluripotent stem cells (iPS and piPS cells). This review highlights the advantages and disadvantages of each of these technologies, with particular emphasis on epigenetic stability. PMID:20162468

  5. Single cell-type comparative metabolomics of epidermal bladder cells from the halophyte Mesembryanthemum crystallinum

    PubMed Central

    Barkla, Bronwyn J.; Vera-Estrella, Rosario

    2015-01-01

    One of the remarkable adaptive features of the halophyte Mesembryanthemum crystallinum are the specialized modified trichomes called epidermal bladder cells (EBC) which cover the leaves, stems, and peduncle of the plant. They are present from an early developmental stage but upon salt stress rapidly expand due to the accumulation of water and sodium. This particular plant feature makes it an attractive system for single cell type studies, with recent proteomics and transcriptomics studies of the EBC establishing that these cells are metabolically active and have roles other than sodium sequestration. To continue our investigation into the function of these unusual cells we carried out a comprehensive global analysis of the metabolites present in the EBC extract by gas chromatography Time-of-Flight mass spectrometry (GC-TOF) and identified 194 known and 722 total molecular features. Statistical analysis of the metabolic changes between control and salt-treated samples identified 352 significantly differing metabolites (268 after correction for FDR). Principal components analysis provided an unbiased evaluation of the data variance structure. Biochemical pathway enrichment analysis suggested significant perturbations in 13 biochemical pathways as defined in KEGG. More than 50% of the metabolites that show significant changes in the EBC, can be classified as compatible solutes and include sugars, sugar alcohols, protein and non-protein amino acids, and organic acids, highlighting the need to maintain osmotic homeostasis to balance the accumulation of Na+ and Cl− ions. Overall, the comparison of metabolic changes in salt treated relative to control samples suggests large alterations in M. crystallinum epidermal bladder cells. PMID:26113856

  6. Characterization of stem/progenitor cell cycle using murine circumvallate papilla taste bud organoid

    PubMed Central

    Aihara, Eitaro; Mahe, Maxime M.; Schumacher, Michael A.; Matthis, Andrea L.; Feng, Rui; Ren, Wenwen; Noah, Taeko K.; Matsu-ura, Toru; Moore, Sean R.; Hong, Christian I.; Zavros, Yana; Herness, Scott; Shroyer, Noah F.; Iwatsuki, Ken; Jiang, Peihua; Helmrath, Michael A.; Montrose, Marshall H.

    2015-01-01

    Leucine-rich repeat-containing G-protein coupled receptor 5-expressing (Lgr5+) cells have been identified as stem/progenitor cells in the circumvallate papillae, and single cultured Lgr5+ cells give rise to taste cells. Here we use circumvallate papilla tissue to establish a three-dimensional culture system (taste bud organoids) that develops phenotypic characteristics similar to native tissue, including a multilayered epithelium containing stem/progenitor in the outer layers and taste cells in the inner layers. Furthermore, characterization of the cell cycle of the taste bud progenitor niche reveals striking dynamics of taste bud development and regeneration. Using this taste bud organoid culture system and FUCCI2 transgenic mice, we identify the stem/progenitor cells have at least 5 distinct cell cycle populations by tracking within 24-hour synchronized oscillations of proliferation. Additionally, we demonstrate that stem/progenitor cells have motility to form taste bud organoids. Taste bud organoids provides a system for elucidating mechanisms of taste signaling, disease modeling, and taste tissue regeneration. PMID:26597788

  7. Repulsive cues combined with physical barriers and cell-cell adhesion determine progenitor cell positioning during organogenesis.

    PubMed

    Paksa, Azadeh; Bandemer, Jan; Hoeckendorf, Burkhard; Razin, Nitzan; Tarbashevich, Katsiaryna; Minina, Sofia; Meyen, Dana; Biundo, Antonio; Leidel, Sebastian A; Peyrieras, Nadine; Gov, Nir S; Keller, Philipp J; Raz, Erez

    2016-01-01

    The precise positioning of organ progenitor cells constitutes an essential, yet poorly understood step during organogenesis. Using primordial germ cells that participate in gonad formation, we present the developmental mechanisms maintaining a motile progenitor cell population at the site where the organ develops. Employing high-resolution live-cell microscopy, we find that repulsive cues coupled with physical barriers confine the cells to the correct bilateral positions. This analysis revealed that cell polarity changes on interaction with the physical barrier and that the establishment of compact clusters involves increased cell-cell interaction time. Using particle-based simulations, we demonstrate the role of reflecting barriers, from which cells turn away on contact, and the importance of proper cell-cell adhesion level for maintaining the tight cell clusters and their correct positioning at the target region. The combination of these developmental and cellular mechanisms prevents organ fusion, controls organ positioning and is thus critical for its proper function. PMID:27088892

  8. Label-Retaining Cells in the Adult Murine Salivary Glands Possess Characteristics of Adult Progenitor Cells

    PubMed Central

    Chibly, Alejandro M.; Querin, Lauren; Harris, Zoey; Limesand, Kirsten H.

    2014-01-01

    Radiotherapy is the primary treatment for patients with head and neck cancer, which account for roughly 500,000 annual cases worldwide. Dysfunction of the salivary glands and associated conditions like xerostomia and dysphagia are often developed by these patients, greatly diminishing their life quality. Current preventative and palliative care fail to deliver an improvement in the quality of life, thus accentuating the need for regenerative therapies. In this study, a model of label retaining cells (LRCs) in murine salivary glands was developed, in which LRCs demonstrated proliferative potential and possessed markers of putative salivary progenitors. Mice were labeled with 5-Ethynyl-2′-deoxyuridine (EdU) at postnatal day 10 and chased for 8 weeks. Tissue sections from salivary glands obtained at the end of chase demonstrated co-localization between LRCs and the salivary progenitor markers keratin 5 and keratin 14, as well as kit mRNA, indicating that LRCs encompass a heterogeneous population of salivary progenitors. Proliferative potential of LRCs was demonstrated by a sphere assay, in which LRCs were found in primary and secondary spheres and they co-localized with the proliferation marker Ki67 throughout sphere formation. Surprisingly, LRCs were shown to be radio-resistant and evade apoptosis following radiation treatment. The clinical significance of these findings lie in the potential of this model to study the mechanisms that prevent salivary progenitors from maintaining homeostasis upon exposure to radiation, which will in turn facilitate the development of regenerative therapies for salivary gland dysfunction. PMID:25238060

  9. Dysregulation of Vascular Endothelial Progenitor Cells Lung-Homing in Subjects with COPD

    PubMed Central

    Salter, Brittany M.; Manzoor, Fizza; Beaudin, Suzanne; Kjarsgaard, Melanie; Nair, Parameswaran; Gauvreau, Gail M.; Sehmi, Roma

    2016-01-01

    Chronic obstructive pulmonary disease (COPD) is characterized by fixed airflow limitation and progressive decline of lung function and punctuated by occasional exacerbations. The disease pathogenesis may involve activation of the bone marrow stimulating mobilization and lung-homing of progenitor cells. We investigated the hypothesis that lower circulating numbers of vascular endothelial progenitor cells (VEPCs) are a consequence of increased lung-sequestration in COPD. Nonatopic, current or ex-smokers with diagnosed COPD and nonatopic, nonsmoking normal controls were enrolled. Blood and induced sputum extracted primitive hemopoietic progenitors (HPCs) and VEPC were enumerated by flow cytometry. Migration and adhesive responses to fibronectin were assessed. In sputum, VEPC numbers were significantly greater in COPD compared to normal controls. In blood, VEPCs were significantly lower in COPD versus normal controls. There were no differences in HPC levels between the two groups in either compartment. Functionally, there was a greater migrational responsiveness of progenitors from COPD subjects to stromal cell-derived factor-1alpha (SDF-1α) compared to normal controls. This was associated with greater numbers of CXCR4+ progenitors in sputum from COPD. Increased migrational responsiveness of progenitor cells may promote lung-homing of VEPC in COPD which may disrupt maintenance and repair of the airways and contribute to COPD disease pathogenesis. PMID:27445517

  10. Exercise-Induced Skeletal Muscle Adaptations Alter the Activity of Adipose Progenitor Cells

    PubMed Central

    Graff, Jonathan M.

    2016-01-01

    Exercise decreases adiposity and improves metabolic health; however, the physiological and molecular underpinnings of these phenomena remain unknown. Here, we investigate the effect of endurance training on adipose progenitor lineage commitment. Using mice with genetically labeled adipose progenitors, we show that these cells react to exercise by decreasing their proliferation and differentiation potential. Analyses of mouse models that mimic the skeletal muscle adaptation to exercise indicate that muscle, in a non-autonomous manner, regulates adipose progenitor homeostasis, highlighting a role for muscle-derived secreted factors. These findings support a humoral link between skeletal muscle and adipose progenitors and indicate that manipulation of adipose stem cell function may help address obesity and diabetes. PMID:27015423

  11. Exercise-Induced Skeletal Muscle Adaptations Alter the Activity of Adipose Progenitor Cells.

    PubMed

    Zeve, Daniel; Millay, Douglas P; Seo, Jin; Graff, Jonathan M

    2016-01-01

    Exercise decreases adiposity and improves metabolic health; however, the physiological and molecular underpinnings of these phenomena remain unknown. Here, we investigate the effect of endurance training on adipose progenitor lineage commitment. Using mice with genetically labeled adipose progenitors, we show that these cells react to exercise by decreasing their proliferation and differentiation potential. Analyses of mouse models that mimic the skeletal muscle adaptation to exercise indicate that muscle, in a non-autonomous manner, regulates adipose progenitor homeostasis, highlighting a role for muscle-derived secreted factors. These findings support a humoral link between skeletal muscle and adipose progenitors and indicate that manipulation of adipose stem cell function may help address obesity and diabetes. PMID:27015423

  12. Characterization of Endothelial Progenitor Cell Interactions with Human Tropoelastin

    PubMed Central

    Yu, Young; Wise, Steven G.; Michael, Praveesuda L.; Bax, Daniel V.; Yuen, Gloria S. C.; Hiob, Matti A.; Yeo, Giselle C.; Filipe, Elysse C.; Dunn, Louise L.; Chan, Kim H.; Hajian, Hamid; Celermajer, David S.; Weiss, Anthony S.; Ng, Martin K. C.

    2015-01-01

    The deployment of endovascular implants such as stents in the treatment of cardiovascular disease damages the vascular endothelium, increasing the risk of thrombosis and promoting neointimal hyperplasia. The rapid restoration of a functional endothelium is known to reduce these complications. Circulating endothelial progenitor cells (EPCs) are increasingly recognized as important contributors to device re-endothelialization. Extracellular matrix proteins prominent in the vessel wall may enhance EPC-directed re-endothelialization. We examined attachment, spreading and proliferation on recombinant human tropoelastin (rhTE) and investigated the mechanism and site of interaction. EPCs attached and spread on rhTE in a dose dependent manner, reaching a maximal level of 56±3% and 54±3%, respectively. EPC proliferation on rhTE was comparable to vitronectin, fibronectin and collagen. EDTA, but not heparan sulfate or lactose, reduced EPC attachment by 81±3%, while full attachment was recovered after add-back of manganese, inferring a classical integrin-mediated interaction. Integrin αVβ3 blocking antibodies decreased EPC adhesion and spreading on rhTE by 39±3% and 56±10% respectively, demonstrating a large contribution from this specific integrin. Attachment of EPCs on N-terminal rhTE constructs N25 and N18 accounted for most of this interaction, accompanied by comparable spreading. In contrast, attachment and spreading on N10 was negligible. αVβ3 blocking antibodies reduced EPC spreading on both N25 and N18 by 45±4% and 42±14%, respectively. In conclusion, rhTE supports EPC binding via an integrin mechanism involving αVβ3. N25 and N18, but not N10 constructs of rhTE contribute to EPC binding. The regulation of EPC activity by rhTE may have implications for modulation of the vascular biocompatibility of endovascular implants. PMID:26115013

  13. Characterization of Endothelial Progenitor Cell Interactions with Human Tropoelastin.

    PubMed

    Yu, Young; Wise, Steven G; Michael, Praveesuda L; Bax, Daniel V; Yuen, Gloria S C; Hiob, Matti A; Yeo, Giselle C; Filipe, Elysse C; Dunn, Louise L; Chan, Kim H; Hajian, Hamid; Celermajer, David S; Weiss, Anthony S; Ng, Martin K C

    2015-01-01

    The deployment of endovascular implants such as stents in the treatment of cardiovascular disease damages the vascular endothelium, increasing the risk of thrombosis and promoting neointimal hyperplasia. The rapid restoration of a functional endothelium is known to reduce these complications. Circulating endothelial progenitor cells (EPCs) are increasingly recognized as important contributors to device re-endothelialization. Extracellular matrix proteins prominent in the vessel wall may enhance EPC-directed re-endothelialization. We examined attachment, spreading and proliferation on recombinant human tropoelastin (rhTE) and investigated the mechanism and site of interaction. EPCs attached and spread on rhTE in a dose dependent manner, reaching a maximal level of 56±3% and 54±3%, respectively. EPC proliferation on rhTE was comparable to vitronectin, fibronectin and collagen. EDTA, but not heparan sulfate or lactose, reduced EPC attachment by 81±3%, while full attachment was recovered after add-back of manganese, inferring a classical integrin-mediated interaction. Integrin αVβ3 blocking antibodies decreased EPC adhesion and spreading on rhTE by 39±3% and 56±10% respectively, demonstrating a large contribution from this specific integrin. Attachment of EPCs on N-terminal rhTE constructs N25 and N18 accounted for most of this interaction, accompanied by comparable spreading. In contrast, attachment and spreading on N10 was negligible. αVβ3 blocking antibodies reduced EPC spreading on both N25 and N18 by 45±4% and 42±14%, respectively. In conclusion, rhTE supports EPC binding via an integrin mechanism involving αVβ3. N25 and N18, but not N10 constructs of rhTE contribute to EPC binding. The regulation of EPC activity by rhTE may have implications for modulation of the vascular biocompatibility of endovascular implants. PMID:26115013

  14. Stem Cells and Progenitor Cells for Tissue-Engineered Solutions to Congenital Heart Defects

    PubMed Central

    Gao, Yang; Jacot, Jeffrey G

    2015-01-01

    Synthetic patches and fixed grafts currently used in the repair of congenital heart defects are nonliving, noncontractile, and not electrically responsive, leading to increased risk of complication, reoperation, and sudden cardiac death. Studies suggest that tissue-engineered patches made from living, functional cells could grow with the patient, facilitate healing, and help recover cardiac function. In this paper, we review the research into possible sources of cardiomyocytes and other cardiac cells, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, adipose-derived stem cells, umbilical cord blood cells, amniotic fluid-derived stem cells, and cardiac progenitor cells. Each cell source has advantages, but also has technical hurdles to overcome, including heterogeneity, functional maturity, immunogenicity, and pathogenicity. Additionally, biomaterials used as patch materials will need to attract and support desired cells and induce minimal immune responses. PMID:26379417

  15. Tissue-resident mesenchymal stem/progenitor cells in skeletal muscle: collaborators or saboteurs?

    PubMed Central

    Judson, Robert N.; Zhang, Regan-Heng; Rossi, Fabio M. A.

    2016-01-01

    Although the regenerative potential of adult skeletal muscle is maintained by satellite cells, other stem/progenitor cell populations also reside in skeletal muscle. These heterogeneous cellular pools with mesenchymal lineage potentially play important roles in tissue homeostasis, with reciprocal collaborations between these cells and satellite cells appearing critical for effective regeneration. However, in disease settings, these mesenchymal stem/progenitors adopt a more sinister role – likely providing a major source of fibrosis, fatty tissue and extracellular matrix protein deposition in dystrophic tissue. Development of therapies for muscle degeneration therefore requires complete understanding of the multiple cell types involved and their complex interactions. PMID:23763717

  16. Calorie Restriction Alleviates Age-Related Decrease in Neural Progenitor Cell Division in the Aging Brain

    PubMed Central

    Park, June-Hee; Glass, Zachary; Sayed, Kasim; Michurina, Tatyana V.; Lazutkin, Alexander; Mineyeva, Olga; Velmeshev, Dmitry; Ward, Walter F.; Richardson, Arlan; Enikolopov, Grigori

    2013-01-01

    Production of new neurons from stem cells is important for cognitive function, and the reduction of neurogenesis in the aging brain may contribute to the accumulation of age-related cognitive deficits. Restriction of calorie intake and prolonged treatment with rapamycin have been shown to extend the lifespan of animals and delay the onset of age-related decline in tissue and organ function. Using a reporter line in which neural stem and progenitor cells are marked by the expression of GFP, we examined the effect of prolonged exposure to calorie restriction (CR) or rapamycin on hippocampal neural stem and progenitor cell proliferation in aging mice. We show that CR increases the number of dividing cells in the dentate gyrus (DG) of female mice. The majority of these cells corresponded to Nestin-GFP-expressing neural stem or progenitor cells; however, this increased proliferative activity of stem and progenitor cells did not result in a significant increase in the number of doublecortin-positive newborn neurons. Our results suggest that restricted calorie intake may increase the number of divisions that neural stem and progenitor cells undergo in the aging brain of females. PMID:23773068

  17. Postnatal epithelium and mesenchyme stem/progenitor cells in bioengineered amelogenesis and dentinogenesis.

    PubMed

    Jiang, Nan; Zhou, Jian; Chen, Mo; Schiff, Michael D; Lee, Chang H; Kong, Kimi; Embree, Mildred C; Zhou, Yanheng; Mao, Jeremy J

    2014-02-01

    Rodent incisors provide a classic model for studying epithelial-mesenchymal interactions in development. However, postnatal stem/progenitor cells in rodent incisors have not been exploited for tooth regeneration. Here, we characterized postnatal rat incisor epithelium and mesenchyme stem/progenitor cells and found that they formed enamel- and dentin-like tissues in vivo. Epithelium and mesenchyme cells were harvested separately from the apical region of postnatal 4-5 day rat incisors. Epithelial and mesenchymal phenotypes were confirmed by immunocytochemistry, CFU assay and/or multi-lineage differentiation. CK14+, Sox2+ and Lgr5+ epithelium stem cells from the cervical loop enhanced amelogenin and ameloblastin expression upon BMP4 or FGF3 stimulation, signifying their differentiation towards ameloblast-like cells, whereas mesenchyme stem/progenitor cells upon BMP4, BMP7 and Wnt3a treatment robustly expressed Dspp, a hallmark of odontoblastic differentiation. We then control-released microencapsulated BMP4, BMP7 and Wnt3a in transplants of epithelium and mesenchyme stem/progenitor cells in the renal capsule of athymic mice in vivo. Enamel and dentin-like tissues were generated in two integrated layers with specific expression of amelogenin and ameloblastin in the newly formed, de novo enamel-like tissue, and DSP in dentin-like tissue. These findings suggest that postnatal epithelium and mesenchyme stem/progenitor cells can be primed towards bioengineered tooth regeneration. PMID:24345734

  18. Proliferative and toxic effects of ultraviolet light and inflammation on epidermal pigment cells

    SciTech Connect

    Nordlund, J.J.; Ackles, A.E.; Traynor, F.F.

    1981-10-01

    The ear of the mouse is useful for studying the effects of ultraviolet light on epidermal pigment cells. The quantity of light penetrating into the skin causing an inflammatory response can be assessed easily by measuring with an engineering calipers the swelling of the ear. The inflammatory response of the ear exhibits a linear relationship to the dose of light delivered. We observed that doses of shortwave ultraviolet light which are noninflammatory when repeated at daily intervals induce moderate to severe inflammation. Small doses of psoralen and prolonged exposure to UVA (PUVA) were more inflammatory than larger amounts of psoralen and short exposure to light. Doses of shortwave ultraviolet light and PUVA which produce only a minimal inflammation of the skin stimulate the proliferation of epidermal melanocytes. In contrast, PUVA in doses sufficiently large to cause a marked inflammatory reaction in the skin seems injurious to pigment cells and kills them or causes only a minimal proliferative response. The inflammatory reaction itself does not seem to stimulate or inhibit the proliferation of melanocytes. Prostaglandins A, E, and F2 alpha have no effect on the proliferation of epidermal pigment cells. In contrast, dimethyl sulfoxide (DMSO) and allergic contact dermatitis increase the numerical density of pigment cells. Steroids may block the function of the enzyme tyrosinase. Our experiments indicate that pigment cells, like many other varieties of cells, are susceptible to injury and can be killed at least by large doses of PUVA.

  19. Epidermal differentiation gene regulatory networks controlled by MAF and MAFB.

    PubMed

    Labott, Andrew T; Lopez-Pajares, Vanessa

    2016-06-01

    Numerous regulatory factors in epidermal differentiation and their role in regulating different cell states have been identified in recent years. However, the genetic interactions between these regulators over the dynamic course of differentiation have not been studied. In this Extra-View article, we review recent work by Lopez-Pajares et al. that explores a new regulatory network in epidermal differentiation. They analyze the changing transcriptome throughout epidermal regeneration to identify 3 separate gene sets enriched in the progenitor, early and late differentiation states. Using expression module mapping, MAF along with MAFB, are identified as transcription factors essential for epidermal differentiation. Through double knock-down of MAF:MAFB using siRNA and CRISPR/Cas9-mediated knockout, epidermal differentiation was shown to be impaired both in-vitro and in-vivo, confirming MAF:MAFB's role to activate genes that drive differentiation. Lopez-Pajares and collaborators integrated 42 published regulator gene sets and the MAF:MAFB gene set into the dynamic differentiation gene expression landscape and found that lncRNAs TINCR and ANCR act as upstream regulators of MAF:MAFB. Furthermore, ChIP-seq analysis of MAF:MAFB identified key transcription factor genes linked to epidermal differentiation as downstream effectors. Combined, these findings illustrate a dynamically regulated network with MAF:MAFB as a crucial link for progenitor gene repression and differentiation gene activation. PMID:27097296

  20. Isolation and characterization of portal branch ligation-stimulated Hmga2-positive bipotent hepatic progenitor cells

    SciTech Connect

    Sakai, Hiroshi; Tagawa, Yoh-ichi; Tamai, Miho; Motoyama, Hiroaki; Ogawa, Shinichiro; Soeda, Junpei; Nakata, Takenari; Miyagawa, Shinichi

    2010-12-17

    Research highlights: {yields} Hepatic progenitor cells were isolated from the portal branch-ligated liver of mice. {yields} Portal branch ligation-stimulated hepatic progenitor cells (PBLHCs) express Hmga2. {yields} PBLHCs have bidirectional differentiation capability in vitro. -- Abstract: Hepatic stem/progenitor cells are one of several cell sources that show promise for restoration of liver mass and function. Although hepatic progenitor cells (HPCs), including oval cells, are induced by administration of certain hepatotoxins in experimental animals, such a strategy would be inappropriate in a clinical setting. Here, we investigated the possibility of isolating HPCs in a portal branch-ligated liver model without administration of any chemical agents. A non-parenchymal cell fraction was prepared from the portal branch-ligated or non-ligated lobe, and seeded onto plates coated with laminin. Most of the cells died, but a small number were able to proliferate. These proliferating cells were cloned as portal branch ligation-stimulated hepatic cells (PBLHCs) by the limiting dilution method. The PBLHCs expressed cytokeratin19, albumin, and Hmga2. The PBLHCs exhibited metabolic functions such as detoxification of ammonium ions and synthesis of urea on Matrigel-coated plates in the presence of oncostatin M. In Matrigel mixed with type I collagen, the PBLHCs became rearranged into cystic and tubular structures. Immunohistochemical staining demonstrated the presence of Hmga2-positive cells around the interlobular bile ducts in the portal branch-ligated liver lobes. In conclusion, successful isolation of bipotent hepatic progenitor cell clones, PBLHCs, from the portal branch-ligated liver lobes of mice provides the possibility of future clinical application of portal vein ligation to induce hepatic progenitor cells.

  1. Adrenocortical Stem and Progenitor Cells: Unifying Model of Two Proposed Origins

    PubMed Central

    Wood, Michelle A.; Hammer, Gary D.

    2010-01-01

    The origins of our understanding of the cellular and molecular mechanisms by which signaling pathways and downstream transcription factors coordinate the specification of adrenocortical cells within the adrenal gland have arisen from studies on the role of Sf1 in steroidogenesis and adrenal development initiated 20 years ago in the laboratory of Dr. Keith Parker. Adrenocortical stem/progenitor cells have been predicted to be undifferentiated and quiescent cells that remain at the periphery of the cortex until needed to replenish the organ, at which time they undergo proliferation and terminal differentiation. Identification of these stem/progenitor cells has only recently been explored. Recent efforts have examined signaling molecules, including Wnt, Shh, and Dax1, which may coordinate intricate lineage and signaling relationships between the adrenal capsule (stem cell niche) and underlying cortex (progenitor cell pool) to maintain organ homeostasis in the adrenal gland. PMID:21094677

  2. The number of fetal nephron progenitor cells limits ureteric branching and adult nephron endowment.

    PubMed

    Cebrian, Cristina; Asai, Naoya; D'Agati, Vivette; Costantini, Frank

    2014-04-10

    Nephrons, the functional units of the kidney, develop from progenitor cells (cap mesenchyme [CM]) surrounding the epithelial ureteric bud (UB) tips. Reciprocal signaling between UB and CM induces nephrogenesis and UB branching. Although low nephron number is implicated in hypertension and renal disease, the mechanisms that determine nephron number are obscure. To test the importance of nephron progenitor cell number, we genetically ablated 40% of these cells, asking whether this would limit kidney size and nephron number or whether compensatory mechanisms would allow the developing organ to recover. The reduction in CM cell number decreased the rate of branching, which in turn allowed the number of CM cells per UB tip to normalize, revealing a self-correction mechanism. However, the retarded UB branching impaired kidney growth, leaving a permanent nephron deficit. Thus, the number of fetal nephron progenitor cells is an important determinant of nephron endowment, largely via its effect on UB branching. PMID:24656820

  3. Response of hemopoietic, progenitor, and multipotent mesenchymal stromal cells to administration of ketanserin during pulmonary fibrosis.

    PubMed

    Dygai, A M; Skurikhin, E G; Pershina, O V; Stepanova, I E; Khmelevskaya, E S; Ermakova, N N; Reztsova, A M; Krupin, V A; Reikhart, D V; Goldberg, V E

    2014-11-01

    We studied the effect of ketanserin on hemopoietic progenitor cells (Lin(-)Sca-1(+)c-Kit(+)CD34- and Lin(-)Sca-1(+)c-Kit(+)CD34(+)), progenitor hemopoietic cells (Lin(-)Sca-1(+)c-kit(+)), and multipotent mesenchymal stromal cells (CD45(-)CD73(+)CD106(+)) in C57Bl/6 mice during pulmonary fibrosis. It was shown that the blocker of 5-HT2A receptors lowers the activity of bleomycin-induced inflammation in the lungs and prevents the infiltration of alveolar interstitium and alveolar ducts by hemopoietic stem and hemopoietic progenitor cells; in this case, they are more numerous in the bone marrow of sick animals. Ketanserin reduces the capacity for self-renewal of lung multipotent mesenchymal stromal cells in the fibrotic phase of the disease and inhibits their differentiation into stromal cell lines (adipocytes, chondrocytes, and fibroblasts) simultaneously with the decrease in the percentage of connective tissue in the lung parenchyma. PMID:25403389

  4. Human mesenchymal and murine stromal cells support human lympho-myeloid progenitor expansion but not maintenance of multipotent haematopoietic stem and progenitor cells.

    PubMed

    Radtke, Stefan; Görgens, André; Liu, Bing; Horn, Peter A; Giebel, Bernd

    2016-02-16

    A major goal in haematopoietic stem cell (HSC) research is to define conditions for the expansion of HSCs or multipotent progenitor cells (MPPs). Since human HSCs/MPPs cannot be isolated, NOD/SCID repopulating cell (SRC) assays emerged as the standard for the quantification of very primitive haematopoietic cell. However, in addition to HSCs/MPPs, lympho-myeloid primed progenitors (LMPPs) were recently found to contain SRC activities, challenging this assay as clear HSC/MPP readout. Because our revised model of human haematopoiesis predicts that HSCs/MPPs can be identified as CD133(+)CD34(+) cells containing erythroid potentials, we investigated the potential of human mesenchymal and conventional murine stromal cells to support expansion of HSCs/MPPs. Even though all stromal cells supported expansion of CD133(+)CD34(+) progenitors with long-term myeloid and long-term lymphoid potentials, erythroid potentials were exclusively found within erythro-myeloid CD133(low)CD34(+) cell fractions. Thus, our data demonstrate that against the prevailing assumption co-cultures on human mesenchymal and murine stromal cells neither promote expansion nor maintenance of HSCs and MPPs. PMID:26818432

  5. Isolation, Expansion and Transplantation of Postnatal Murine Progenitor Cells of the Enteric Nervous System

    PubMed Central

    Dettmann, Heike Monika; Zhang, Ying; Wronna, Nadine; Kraushaar, Udo; Guenther, Elke; Mohr, Roland; Neckel, Peter Helmut; Mack, Andreas; Fuchs, Joerg; Just, Lothar; Obermayr, Florian

    2014-01-01

    Neural stem or progenitor cells have been proposed to restore gastrointestinal function in patients suffering from congenital or acquired defects of the enteric nervous system. Various, mainly embryonic cell sources have been identified for this purpose. However, immunological and ethical issues make a postnatal cell based therapy desirable. We therefore evaluated and quantified the potential of progenitor cells of the postnatal murine enteric nervous system to give rise to neurons and glial cells in vitro. Electrophysiological analysis and BrdU uptake studies provided direct evidence that generated neurons derive from expanded cells in vitro. Transplantation of isolated and expanded postnatal progenitor cells into the distal colon of adult mice demonstrated cell survival for 12 weeks (end of study). Implanted cells migrated within the gut wall and differentiated into neurons and glial cells, both of which were shown to derive from proliferated cells by BrdU uptake. This study indicates that progenitor cells isolated from the postnatal enteric nervous system might have the potential to serve as a source for a cell based therapy for neurogastrointestinal motility disorders. However, further studies are necessary to provide evidence that the generated cells are capable to positively influence the motility of the diseased gastrointestinal tract. PMID:24871092

  6. The Androgen Receptor Antagonizes Wnt/β-Catenin Signaling in Epidermal Stem Cells

    PubMed Central

    Kretzschmar, Kai; Cottle, Denny L; Schweiger, Pawel J; Watt, Fiona M

    2015-01-01

    Activation of Wnt/β-catenin signaling in adult mouse epidermis leads to expansion of the stem cell compartment and redirects keratinocytes in the interfollicular epidermis and sebaceous glands (SGs) to differentiate along the hair follicle (HF) lineages. Here we demonstrate that during epidermal development and homeostasis there is reciprocal activation of the androgen receptor (AR) and β-catenin in cells of the HF bulb. AR activation reduced β-catenin-dependent transcription, blocked β-catenin-induced induction of HF growth, and prevented β-catenin-mediated conversion of SGs into HFs. Conversely, AR inhibition enhanced the effects of β-catenin activation, promoting HF proliferation and differentiation, culminating in the formation of benign HF tumors and a complete loss of SG identity. We conclude that AR signaling has a key role in epidermal stem cell fate selection by modulating responses to β-catenin in adult mouse skin. PMID:26121213

  7. Human epidermal neural crest stem cells as a source of Schwann cells

    PubMed Central

    Sakaue, Motoharu; Sieber-Blum, Maya

    2015-01-01

    We show that highly pure populations of human Schwann cells can be derived rapidly and in a straightforward way, without the need for genetic manipulation, from human epidermal neural crest stem cells [hEPI-NCSC(s)] present in the bulge of hair follicles. These human Schwann cells promise to be a useful tool for cell-based therapies, disease modelling and drug discovery. Schwann cells are glia that support axons of peripheral nerves and are direct descendants of the embryonic neural crest. Peripheral nerves are damaged in various conditions, including through trauma or tumour-related surgery, and Schwann cells are required for their repair and regeneration. Schwann cells also promise to be useful for treating spinal cord injuries. Ex vivo expansion of hEPI-NCSC isolated from hair bulge explants, manipulating the WNT, sonic hedgehog and TGFβ signalling pathways, and exposure of the cells to pertinent growth factors led to the expression of the Schwann cell markers SOX10, KROX20 (EGR2), p75NTR (NGFR), MBP and S100B by day 4 in virtually all cells, and maturation was completed by 2 weeks of differentiation. Gene expression profiling demonstrated expression of transcripts for neurotrophic and angiogenic factors, as well as JUN, all of which are essential for nerve regeneration. Co-culture of hEPI-NCSC-derived human Schwann cells with rodent dorsal root ganglia showed interaction of the Schwann cells with axons, providing evidence of Schwann cell functionality. We conclude that hEPI-NCSCs are a biologically relevant source for generating large and highly pure populations of human Schwann cells. PMID:26251357

  8. In Vitro Differentiation and Expansion of Human Pluripotent Stem Cell-Derived Pancreatic Progenitors

    PubMed Central

    Chmielowiec, Jolanta; Borowiak, Malgorzata

    2014-01-01

    Recent progress in understanding stem cell biology has been remarkable, especially in deciphering signals that support differentiation towards tissue-specific lineages. This achievement positions us firmly at the beginning of an era of patient-specific regenerative medicine and human disease modeling. It will be necessary to equip the progress in this era with a reliable source of self-renewing progenitor cells that differentiate into functional target cells. The generation of pancreatic progenitors that mature in vivo into functional beta-cells has raised the hope for new therapeutic options in diabetes, but key challenges still remain including the production of sufficient numbers of cells for research and transplantation. Recent approaches to this problem have shown that the presence of organ- and stage-specific mesenchyme improves the generation of progenitors, from endoderm to endocrine cells. Alternatively, utilization of three-dimensional culture may improve the efficiency and yield of directed differentiation. Here, we review the current knowledge of pancreatic directed differentiation and ex vivo expansion of pancreatic progenitors, including recent advances in differentiation strategies for the generation of pancreatic progenitors, and we discuss persistent challenges which will need to be overcome before personalized cell-based therapy becomes a practical strategy. PMID:25148365

  9. Myelination in vitro of rodent dorsal root ganglia by glial progenitor cells.

    PubMed

    Zajicek, J; Compston, A

    1994-12-01

    Oligodendrocytes synthesize myelin in the mammalian central nervous system; they develop from glial progenitors which, at least in vitro, are bipotential and also differentiate into astrocytes. Maturation of these O-2A progenitors is known to be influenced by growth factors and by extracellular matrix molecules. We investigated the effect of neurons on glial development by co-culturing highly purified rodent embryonic dorsal root ganglia with neonatal O-2A progenitors. Neurons produce signals, including platelet-derived growth factor BB and basic fibroblast growth factor, which stimulate progenitor cells to synthesize DNA; axonal contact is associated with down-regulation in the expression of complex ganglioside surface molecules on O-2A progenitors; with maturation, many of these cells develop into oligodendrocytes allowing the normal process of myelination to take place, but neurons also promote the differentiation of type 2 astrocytes. This orchestration of proliferation and differentiation in O-2A progenitor cells favours the development of glial-neuronal interactions needed for saltatory conduction of the nerve impulse. PMID:7820570

  10. Neuropilin 1 expression correlates with differentiation status of epidermal cells and cutaneous squamous cell carcinomas.

    PubMed

    Shahrabi-Farahani, Shokoufeh; Wang, Lili; Zwaans, Bernadette M M; Santana, Jeans M; Shimizu, Akio; Takashima, Seiji; Kreuter, Michael; Coultas, Leigh; D'Amore, Patricia A; Arbeit, Jeffrey M; Akslen, Lars A; Bielenberg, Diane R

    2014-07-01

    Neuropilins (NRPs) are cell surface receptors for vascular endothelial growth factor (VEGF) and SEMA3 (class 3 semaphorin) family members. The role of NRPs in neurons and endothelial cells has been investigated, but the expression and role of NRPs in epithelial cells is much less clear. Herein, the expression and localization of NRP1 was investigated in human and mouse skin and squamous cell carcinomas (SCCs). Results indicated that NRP1 mRNA and protein was expressed in the suprabasal epithelial layers of the skin sections. NRP1 staining did not overlap with that of keratin 14 (K14) or proliferating cell nuclear antigen, but did co-localize with staining for keratin 1, indicating that differentiated keratinocytes express NRP1. Similar to the expression of NRP1, VEGF-A was expressed in suprabasal epithelial cells, whereas Nrp2 and VEGFR2 were not detectable in the epidermis. The expression of NRP1 correlated with a high degree of differentiation in human SCC specimens, human SCC xenografts, and mouse K14-HPV16 transgenic SCC. UVB irradiation of mouse skin induced Nrp1 upregulation. In vitro, Nrp1 was upregulated in primary keratinocytes in response to differentiating media or epidermal growth factor-family growth factors. In conclusion, the expression of NRP1 is regulated in the skin and is selectively produced in differentiated epithelial cells. NRP1 may function as a reservoir to sequester VEGF ligand within the epithelial compartment, thereby modulating its bioactivity. PMID:24791743

  11. Epidermal Notch1 recruits RORγ+ group 3 innate lymphoid cells to orchestrate normal skin repair

    PubMed Central

    Li, Zhi; Hodgkinson, Tom; Gothard, Elizabeth J.; Boroumand, Soulmaz; Lamb, Rebecca; Cummins, Ian; Narang, Priyanka; Sawtell, Amy; Coles, Jenny; Leonov, German; Reboldi, Andrea; Buckley, Christopher D.; Cupedo, Tom; Siebel, Christian; Bayat, Ardeshir; Coles, Mark C.; Ambler, Carrie A.

    2016-01-01

    Notch has a well-defined role in controlling cell fate decisions in the embryo and the adult epidermis and immune systems, yet emerging evidence suggests Notch also directs non-cell-autonomous signalling in adult tissues. Here, we show that Notch1 works as a damage response signal. Epidermal Notch induces recruitment of immune cell subsets including RORγ+ ILC3s into wounded dermis; RORγ+ ILC3s are potent sources of IL17F in wounds and control immunological and epidermal cell responses. Mice deficient for RORγ+ ILC3s heal wounds poorly resulting from delayed epidermal proliferation and macrophage recruitment in a CCL3-dependent process. Notch1 upregulates TNFα and the ILC3 recruitment chemokines CCL20 and CXCL13. TNFα, as a Notch1 effector, directs ILC3 localization and rates of wound healing. Altogether these findings suggest that Notch is a key stress/injury signal in skin epithelium driving innate immune cell recruitment and normal skin tissue repair. PMID:27099134

  12. Epidermal Notch1 recruits RORγ(+) group 3 innate lymphoid cells to orchestrate normal skin repair.

    PubMed

    Li, Zhi; Hodgkinson, Tom; Gothard, Elizabeth J; Boroumand, Soulmaz; Lamb, Rebecca; Cummins, Ian; Narang, Priyanka; Sawtell, Amy; Coles, Jenny; Leonov, German; Reboldi, Andrea; Buckley, Christopher D; Cupedo, Tom; Siebel, Christian; Bayat, Ardeshir; Coles, Mark C; Ambler, Carrie A

    2016-01-01

    Notch has a well-defined role in controlling cell fate decisions in the embryo and the adult epidermis and immune systems, yet emerging evidence suggests Notch also directs non-cell-autonomous signalling in adult tissues. Here, we show that Notch1 works as a damage response signal. Epidermal Notch induces recruitment of immune cell subsets including RORγ(+) ILC3s into wounded dermis; RORγ(+) ILC3s are potent sources of IL17F in wounds and control immunological and epidermal cell responses. Mice deficient for RORγ(+) ILC3s heal wounds poorly resulting from delayed epidermal proliferation and macrophage recruitment in a CCL3-dependent process. Notch1 upregulates TNFα and the ILC3 recruitment chemokines CCL20 and CXCL13. TNFα, as a Notch1 effector, directs ILC3 localization and rates of wound healing. Altogether these findings suggest that Notch is a key stress/injury signal in skin epithelium driving innate immune cell recruitment and normal skin tissue repair. PMID:27099134

  13. Prevention of skin tumorigenesis and impairment of epidermal cell proliferation by targeted aquaporin-3 gene disruption.

    PubMed

    Hara-Chikuma, Mariko; Verkman, A S

    2008-01-01

    Aquaporin-3 (AQP3) is a water/glycerol-transporting protein expressed strongly at the plasma membranes of basal epidermal cells in skin. We found that human skin squamous cell carcinoma strongly overexpresses AQP3. A novel role for AQP3 in skin tumorigenesis was discovered using mice with targeted AQP3 gene disruption. We found that AQP3-null mice were remarkably resistant to the development of skin tumors following exposure to a tumor initiator and phorbol ester promoter. Though tumor initiator challenge produced comparable apoptotic responses in wild-type and AQP3-null mice, promoter-induced cell proliferation was greatly impaired in the AQP3-null epidermis. Reductions of epidermal cell glycerol, its metabolite glycerol-3-phosphate, and ATP were found in AQP3 deficiency without impairment of mitochondrial function. Glycerol supplementation corrected the reduced proliferation and ATP content in AQP3 deficiency, with cellular glycerol, ATP, and proliferative ability being closely correlated. Our data suggest involvement of AQP3-facilitated glycerol transport in epidermal cell proliferation and tumorigenesis by a novel mechanism implicating cellular glycerol as a key determinant of cellular ATP energy. AQP3 may thus be an important determinant in skin tumorigenesis and hence a novel target for tumor prevention and therapy. PMID:17967887

  14. Generation of an expandable intermediate mesoderm restricted progenitor cell line from human pluripotent stem cells

    PubMed Central

    Kumar, Nathan; Richter, Jenna; Cutts, Josh; Bush, Kevin T; Trujillo, Cleber; Nigam, Sanjay K; Gaasterland, Terry; Brafman, David; Willert, Karl

    2015-01-01

    The field of tissue engineering entered a new era with the development of human pluripotent stem cells (hPSCs), which are capable of unlimited expansion whilst retaining the potential to differentiate into all mature cell populations. However, these cells harbor significant risks, including tumor formation upon transplantation. One way to mitigate this risk is to develop expandable progenitor cell populations with restricted differentiation potential. Here, we used a cellular microarray technology to identify a defined and optimized culture condition that supports the derivation and propagation of a cell population with mesodermal properties. This cell population, referred to as intermediate mesodermal progenitor (IMP) cells, is capable of unlimited expansion, lacks tumor formation potential, and, upon appropriate stimulation, readily acquires properties of a sub-population of kidney cells. Interestingly, IMP cells fail to differentiate into other mesodermally-derived tissues, including blood and heart, suggesting that these cells are restricted to an intermediate mesodermal fate. DOI: http://dx.doi.org/10.7554/eLife.08413.001 PMID:26554899

  15. The in vitro generation of lung and airway progenitor cells from human pluripotent stem cells

    PubMed Central

    Huang, Sarah X L; Green, Michael D; de Carvalho, Ana Toste; Mumau, Melanie; Chen, Ya-Wen; D’Souza, Sunita L.; Snoeck, Hans-Willem

    2015-01-01

    Lung and airway epithelial cells generated in vitro from human pluripotent stem cells have applications in regenerative medicine, modeling of lung disease, drug screening and studies of human lung development. Here we describe a strategy for directed differentiation of human pluripotent stem cells into developmental lung progenitors, and their subsequent differentiation into predominantly distal lung epithelial cells. The protocol entails four stages that recapitulate lung development and takes approximately 50 days. First, definitive endoderm is induced in the presence of high concentrations of Activin A. Subsequently, lung-biased anterior foregut endoderm is specified by sequential inhibition of BMP, TGF-β and Wnt signaling. Anterior foregut endoderm is then ventralized by applying Wnt, BMP, FGF and RA signaling to obtain lung and airway progenitors. Finally, these are further differentiated into more mature epithelial cells types using Wnt, FGF, c-AMP and glucocorticoid agonism. This protocol is conducted in defined conditions, does not involve genetic manipulation of the cells, and results in cultures where the majority of the cells express markers of various lung and airway epithelial cells, with a predominance of cells identifiable as functional type II alveolar epithelial cells. PMID:25654758

  16. JAK-STAT and AKT pathway-coupled genes in erythroid progenitor cells through ontogeny

    PubMed Central

    2012-01-01

    Background It has been reported that the phosphatidylinositol 3-kinase (PI3K)-AKT signaling pathway regulates erythropoietin (EPO)-induced survival, proliferation, and maturation of early erythroid progenitors. Erythroid cell proliferation and survival have also been related to activation of the JAK-STAT pathway. The goal of this study was to observe the function of EPO activation of JAK-STAT and PI3K/AKT pathways in the development of erythroid progenitors from hematopoietic CD34+ progenitor cells, as well as to distinguish early EPO target genes in human erythroid progenitors during ontogeny. Methods Hematopoietic CD34+ progenitor cells, isolated from fetal and adult hematopoietic tissues, were differentiated into erythroid progenitor cells. We have used microarray analysis to examine JAK-STAT and PI3K/AKT related genes, as well as broad gene expression modulation in these human erythroid progenitor cells. Results In microarray studies, a total of 1755 genes were expressed in fetal liver, 3844 in cord blood, 1770 in adult bone marrow, and 1325 genes in peripheral blood-derived erythroid progenitor cells. The erythroid progenitor cells shared 1011 common genes. Using the Ingenuity Pathways Analysis software, we evaluated the network pathways of genes linked to hematological system development, cellular growth and proliferation. The KITLG, EPO, GATA1, PIM1 and STAT3 genes represent the major connection points in the hematological system development linked genes. Some JAK-STAT signaling pathway-linked genes were steadily upregulated throughout ontogeny (PIM1, SOCS2, MYC, PTPN11), while others were downregulated (PTPN6, PIAS, SPRED2). In addition, some JAK-STAT pathway related genes are differentially expressed only in some stages of ontogeny (STATs, GRB2, CREBB). Beside the continuously upregulated (AKT1, PPP2CA, CHUK, NFKB1) and downregulated (FOXO1, PDPK1, PIK3CG) genes in the PI3K-AKT signaling pathway, we also observed intermittently regulated gene expression

  17. Characterization of interstitial Cajal progenitors cells and their changes in Hirschsprung's disease.

    PubMed

    Chen, Zhi-Hua; Zhang, Yong-Chang; Jiang, Wei-Fang; Yang, Cissy; Zou, Gang-Ming; Kong, Yu; Cai, Wei

    2014-01-01

    Interstitial cells of Cajal (ICC) are critical to gastrointestinal motility. The phenotypes of ICC progenitors have been observed in the mouse gut, but whether they exist in the human colon and what abnormal changes in their quantity and ultrastructure are present in Hirschsprung's disease (HSCR) colon remains uncertain. In this study, we collected the surgical resection of colons, both proximal and narrow segments, from HSCR patients and normal controls. First, we identified the progenitor of ICC in normal adult colon using immunofluorescent localization techniques with laser confocal microscopy. Next, the progenitors were sorted to observe their morphology. We further applied flow cytometry to examine the content of ICC progenitors in these fresh samples. The ultrastructural changes in the narrow and proximal parts of the HSCR colon were observed using transmission electron microscopy (TEM) and were compared with the normal adult colon. The presumed early progenitor (c-Kit(low)CD34(+)Igf1r(+)) and committed progenitor (c-Kit(+)CD34(+)Igf1r(+)) of ICC exist in adult normal colon as well as in the narrow and proximal parts of the HSCR colon. However, the proportions of mature, early and committed progenitors of ICC were dramatically reduced in the narrow segment of the HSCR colon. The proportions of mature and committed progenitors of ICC in the proximal segment of the HSCR colon were lower than in the adult normal colon. Ultrastructurally, ICC, enteric nerves, and smooth muscle in the narrow segment of the HSCR colon showed severe injury, including swollen vacuola or ted mitochondria, disappearance of mitochondrial cristae, dilated rough endoplasmic reticulum, vesiculation and degranulation, and disappearance of the caveolae on the ICC membrane surface. The contents of ICC and its progenitors in the narrow part of the HSCR colon were significantly decreased than those of adult colon, which may be associated with HSCR pathogenesis. PMID:24475076

  18. Brief Azacytidine Step Allows The Conversion of Suspension Human Fibroblasts into Neural Progenitor-Like Cells

    PubMed Central

    Mirakhori, Fahimeh; Zeynali, Bahman; Kiani, Sahar; Baharvand, Hossein

    2015-01-01

    In recent years transdifferentiation technology has enabled direct conversion of human fibroblasts to become a valuable, abundant and accessible cell source for patient-specific induced cell generation in biomedical research. The majority of transdifferentiation approaches rely upon viral gene delivery which due to random integration with the host genome can cause genome instability and tumorigenesis upon transplantation. Here, we provide a simple way to induce neural progenitor-like cells from human fibroblasts without genetic manipulation by changing physicochemical culture properties from monolayer culture into a suspension in the presence of a chemical DNA methyltransferase inhibitor agent, Azacytidine. We have demonstrated the expression of neural progenitor-like markers, morphology and the ability to spontaneously differentiate into neural-like cells. This approach is simple, inexpensive, lacks genetic manipulation and could be a foundation for future chemical neural transdifferentiation and a safe induction of neural progenitor cells from human fibroblasts for clinical applications. PMID:25870845

  19. Eupalinilide E inhibits erythropoiesis and promotes the expansion of hematopoietic progenitor cells.

    PubMed

    de Lichtervelde, Lorenzo; Boitano, Anthony E; Wang, Ying; Krastel, Philipp; Petersen, Frank; Cooke, Michael P; Schultz, Peter G

    2013-05-17

    Hematopoietic stem cells (HSCs) are the progenitor cells that give rise to all blood cells. The ability to control HSC differentiation has the potential to improve the success of bone marrow transplants and the production of functional blood cells ex vivo. Here we performed an unbiased screen using primary human CD34(+) hematopoietic stem and progenitor cells (HSPCs) to identify natural products that selectively control their differentiation. We identified a plant-derived natural product, eupalinilide E, that promotes the ex vivo expansion of HSPCs and hinders the in vitro development of erythrocytes. This activity was additive with aryl hydrocarbon receptor (AhR) antagonists, which are also known to expand HSCs and currently in clinical development. These findings reveal a new activity for eupalinilide E, and suggest that it may be a useful tool to probe the mechanisms of hematopoiesis and improve the ex vivo production of progenitors for therapeutic purposes. PMID:23441826

  20. Endothelin-1 supports clonal derivation and expansion of cardiovascular progenitors derived from human embryonic stem cells.

    PubMed

    Soh, Boon-Seng; Ng, Shi-Yan; Wu, Hao; Buac, Kristina; Park, Joo-Hye C; Lian, Xiaojun; Xu, Jiejia; Foo, Kylie S; Felldin, Ulrika; He, Xiaobing; Nichane, Massimo; Yang, Henry; Bu, Lei; Li, Ronald A; Lim, Bing; Chien, Kenneth R

    2016-01-01

    Coronary arteriogenesis is a central step in cardiogenesis, requiring coordinated generation and integration of endothelial cell and vascular smooth muscle cells. At present, it is unclear whether the cell fate programme of cardiac progenitors to generate complex muscular or vascular structures is entirely cell autonomous. Here we demonstrate the intrinsic ability of vascular progenitors to develop and self-organize into cardiac tissues by clonally isolating and expanding second heart field cardiovascular progenitors using WNT3A and endothelin-1 (EDN1) human recombinant proteins. Progenitor clones undergo long-term expansion and differentiate primarily into endothelial and smooth muscle cell lineages in vitro, and contribute extensively to coronary-like vessels in vivo, forming a functional human-mouse chimeric circulatory system. Our study identifies EDN1 as a key factor towards the generation and clonal derivation of ISL1(+) vascular intermediates, and demonstrates the intrinsic cell-autonomous nature of these progenitors to differentiate and self-organize into functional vasculatures in vivo. PMID:26952167

  1. Potential role of endometrial stem/progenitor cells in the pathogenesis of early-onset endometriosis.

    PubMed

    Gargett, C E; Schwab, K E; Brosens, J J; Puttemans, P; Benagiano, G; Brosens, I

    2014-07-01

    The pathogenesis of early-onset endometriosis has recently been revisited, sparked by the discovery of endometrial stem/progenitor cells and their possible role in endometriosis, and because maternal pregnancy hormone withdrawal following delivery induces uterine bleeding in the neonate. The neonatal uterus has a large cervix to corpus ratio which is functionally blocked with mucous, supporting the concept of retrograde shedding of neonatal endometrium. Only 5% show overt bleeding. Furthermore, the presence of endometriosis in pre-menarcheal girls and even in severe stage in adolescents supports the theory that early-onset endometriosis may originate from retrograde uterine bleeding soon after birth. Endometrial stem/progenitor cells have been identified in menstrual blood suggesting that they may also be shed during neonatal uterine bleeding. Thus, we hypothesized that stem/progenitor cells present in shedding endometrium may have a role in the pathogenesis of early-onset endometriosis through retrograde neonatal uterine bleeding. During the neonatal and pre-pubertal period, shed endometrial stem/progenitor cells are postulated to survive in the pelvic cavity in the absence of circulating estrogens supported by niche cells also shed during neonatal uterine bleeding. According to this hypothesis, during thelarche, under the influence of rising estrogen levels, endometrial stem/progenitor cells proliferate and establish ectopic endometrial lesions characteristic of endometriosis. This New Research Horizon review builds on recent discussions on the pathogenesis of early-onset endometriosis and raises new avenues for research into this costly condition. PMID:24674992

  2. Endothelin-1 supports clonal derivation and expansion of cardiovascular progenitors derived from human embryonic stem cells

    PubMed Central

    Soh, Boon-Seng; Ng, Shi-Yan; Wu, Hao; Buac, Kristina; Park, Joo-Hye C.; Lian, Xiaojun; Xu, Jiejia; Foo, Kylie S.; Felldin, Ulrika; He, Xiaobing; Nichane, Massimo; Yang, Henry; Bu, Lei; Li, Ronald A.; Lim, Bing; Chien, Kenneth R.

    2016-01-01

    Coronary arteriogenesis is a central step in cardiogenesis, requiring coordinated generation and integration of endothelial cell and vascular smooth muscle cells. At present, it is unclear whether the cell fate programme of cardiac progenitors to generate complex muscular or vascular structures is entirely cell autonomous. Here we demonstrate the intrinsic ability of vascular progenitors to develop and self-organize into cardiac tissues by clonally isolating and expanding second heart field cardiovascular progenitors using WNT3A and endothelin-1 (EDN1) human recombinant proteins. Progenitor clones undergo long-term expansion and differentiate primarily into endothelial and smooth muscle cell lineages in vitro, and contribute extensively to coronary-like vessels in vivo, forming a functional human–mouse chimeric circulatory system. Our study identifies EDN1 as a key factor towards the generation and clonal derivation of ISL1+ vascular intermediates, and demonstrates the intrinsic cell-autonomous nature of these progenitors to differentiate and self-organize into functional vasculatures in vivo. PMID:26952167

  3. Induction of Excess Centrosomes in Neural Progenitor Cells during the Development of Radiation-Induced Microcephaly

    PubMed Central

    Shimada, Mikio; Matsuzaki, Fumio; Kato, Akihiro; Kobayashi, Junya; Matsumoto, Tomohiro; Komatsu, Kenshi

    2016-01-01

    The embryonic brain is one of the tissues most vulnerable to ionizing radiation. In this study, we showed that ionizing radiation induces apoptosis in the neural progenitors of the mouse cerebral cortex, and that the surviving progenitor cells subsequently develop a considerable amount of supernumerary centrosomes. When mouse embryos at Day 13.5 were exposed to γ-rays, brains sizes were reduced markedly in a dose-dependent manner, and these size reductions persisted until birth. Immunostaining with caspase-3 antibodies showed that apoptosis occurred in 35% and 40% of neural progenitor cells at 4 h after exposure to 1 and 2 Gy, respectively, and this was accompanied by a disruption of the apical layer in which mitotic spindles were positioned in unirradiated mice. At 24 h after 1 Gy irradiation, the apoptotic cells were completely eliminated and proliferation was restored to a level similar to that of unirradiated cells, but numerous spindles were localized outside the apical layer. Similarly, abnormal cytokinesis, which included multipolar division and centrosome clustering, was observed in 19% and 24% of the surviving neural progenitor cells at 48 h after irradiation with 1 and 2 Gy, respectively. Because these cytokinesis aberrations derived from excess centrosomes result in growth delay and mitotic catastrophe-mediated cell elimination, our findings suggest that, in addition to apoptosis at an early stage of radiation exposure, radiation-induced centrosome overduplication could contribute to the depletion of neural progenitors and thereby lead to microcephaly. PMID:27367050

  4. EMT Involved in Migration of Stem/Progenitor Cells for Pituitary Development and Regeneration

    PubMed Central

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    Epithelial–mesenchymal transition (EMT) and cell migration are important processes in embryonic development of many tissues as well as oncogenesis. The pituitary gland is a master endocrine tissue and recent studies indicate that Sox2-expressing stem/progenitor cells actively migrate and develop this tissue during embryogenesis. Notably, although migration activity of stem/progenitor cells in the postnatal period seems to be reduced compared to that in the embryonic period, it is hypothesized that stem/progenitor cells in the adult pituitary re-migrate from their microenvironment niche to contribute to the regeneration system. Therefore, elucidation of EMT in the pituitary stem/progenitor cells will promote understanding of pituitary development and regeneration, as well as diseases such as pituitary adenoma. In this review, so as to gain more insights into the mechanisms of pituitary development and regeneration, we summarize the EMT in the pituitary by focusing on the migration of pituitary stem/progenitor cells during both embryonic and postnatal organogenesis. PMID:27058562

  5. EMT Involved in Migration of Stem/Progenitor Cells for Pituitary Development and Regeneration.

    PubMed

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    Epithelial-mesenchymal transition (EMT) and cell migration are important processes in embryonic development of many tissues as well as oncogenesis. The pituitary gland is a master endocrine tissue and recent studies indicate that Sox2-expressing stem/progenitor cells actively migrate and develop this tissue during embryogenesis. Notably, although migration activity of stem/progenitor cells in the postnatal period seems to be reduced compared to that in the embryonic period, it is hypothesized that stem/progenitor cells in the adult pituitary re-migrate from their microenvironment niche to contribute to the regeneration system. Therefore, elucidation of EMT in the pituitary stem/progenitor cells will promote understanding of pituitary development and regeneration, as well as diseases such as pituitary adenoma. In this review, so as to gain more insights into the mechanisms of pituitary development and regeneration, we summarize the EMT in the pituitary by focusing on the migration of pituitary stem/progenitor cells during both embryonic and postnatal organogenesis. PMID:27058562

  6. Sensitivity of human granulosa cell tumor cells to epidermal growth factor receptor inhibition.

    PubMed

    Andersson, Noora; Anttonen, Mikko; Färkkilä, Anniina; Pihlajoki, Marjut; Bützow, Ralf; Unkila-Kallio, Leila; Heikinheimo, Markku

    2014-04-01

    Epidermal growth factor receptor (EGFR) is implicated in the progression of many human cancers, but its significance in ovarian granulosa cell tumor (GCT) pathobiology remains poorly understood. We assessed the EGFR gene copy number, surveyed the mRNA and protein expression patterns of EGFR in 90 adult GCTs, and assessed the in vitro sensitivity of GCT cells to EGFR inhibition. Low-level amplification of EGFR gene was observed in five GCTs and high-level amplification in one sample. EGFR mRNA was robustly expressed in GCTs. Most tumors expressed both unphosphorylated and phosphorylated EGFR protein, but the protein expression did not correlate with clinical parameters, including the risk of recurrence. Small-molecule EGFR inhibitors reduced the EGF-induced activation of EGFR and its downstream signaling molecules at nanomolar doses, but cell viability was reduced, and caspase-3/7 was activated in GCT cells only at micromolar doses. Based on the present results, EGFR is active and abundantly expressed in the majority of GCTs, but probably has only minor contribution to GCT cell growth. Given the high doses of EGFR inhibitors required to reduce GCT cell viability in vitro, they are not likely to be effective for GCT treatment as single agents; they should rather be tested as part of combination therapies for these malignancies. PMID:24463098

  7. Use of long-term human marrow cultures to demonstrate progenitor cell precursors in marrow treated with 4-hydroperoxycyclophosphamide

    SciTech Connect

    Winton, E.F.; Colenda, K.W.

    1987-07-01

    The continued retrieval of progenitor cells (CFU-GEMM, BFU-E, CFU-E, CFU-GM) from human long-term marrow cultures (LTMC) is not uncommonly used as evidence that proliferation and differentiation are occurring in more primitive hematopoietic stem cells (HSC) in these cultures. Alternatively, the continued presence of progenitors in LTMC could be the result of survival and/or limited self-renewal of progenitor cells present when the culture was initiated, and such progenitors would have little relevance to the parent HSC. The following studies were designed to determine the relative contributions of precursors of progenitor cells to the total progenitor cells present in LTMC using a two-stage regeneration model. The adherent layer in LTMC was established over 3 weeks, irradiated (875 rad) to permanently eliminate resident hematopoietic cells, and recharged with autologous cryo-preserved marrow that was either treated or not treated (control) with 4-hydroperoxycyclophosphamide (4-HC, 100 micrograms/ml for 30 min). The 4-HC-treated marrow contained no progenitor cells, yet based on clinical autologous bone marrow transplant experience, has intact HSC. Within 1-3 weeks, progenitor cells reappeared in the irradiated LTMC recharged with 4-HC-treated marrow, and were preferentially located in the adherent layer. By 2-6 weeks, the number of progenitor cells in the adherent layer of LTMC recharged with 4-HC marrow was equivalent to control LTMC. The progenitors regenerating in the irradiated LTMC recharged with 4-HC-treated marrow appear to originate from precursors of progenitor cells, perhaps HSC. We propose this model may be useful in elucidating cellular and molecular correlates of progenitor cell regeneration from precursors.

  8. Correction of junctional epidermolysis bullosa by transplantation of genetically modified epidermal stem cells.

    PubMed

    Mavilio, Fulvio; Pellegrini, Graziella; Ferrari, Stefano; Di Nunzio, Francesca; Di Iorio, Enzo; Recchia, Alessandra; Maruggi, Giulietta; Ferrari, Giuliana; Provasi, Elena; Bonini, Chiara; Capurro, Sergio; Conti, Andrea; Magnoni, Cristina; Giannetti, Alberto; De Luca, Michele

    2006-12-01

    The continuous renewal of human epidermis is sustained by stem cells contained in the epidermal basal layer and in hair follicles. Cultured keratinocyte stem cells, known as holoclones, generate sheets of epithelium used to restore severe skin, mucosal and corneal defects. Mutations in genes encoding the basement membrane component laminin 5 (LAM5) cause junctional epidermolysis bullosa (JEB), a devastating and often fatal skin adhesion disorder. Epidermal stem cells from an adult patient affected by LAM5-beta3-deficient JEB were transduced with a retroviral vector expressing LAMB3 cDNA (encoding LAM5-beta3), and used to prepare genetically corrected cultured epidermal grafts. Nine grafts were transplanted onto surgically prepared regions of the patient's legs. Engraftment was complete after 8 d. Synthesis and proper assembly of normal levels of functional LAM5 were observed, together with the development of a firmly adherent epidermis that remained stable for the duration of the follow-up (1 year) in the absence of blisters, infections, inflammation or immune response. Retroviral integration site analysis indicated that the regenerated epidermis is maintained by a defined repertoire of transduced stem cells. These data show that ex vivo gene therapy of JEB is feasible and leads to full functional correction of the disease. PMID:17115047

  9. Meis1 Regulates Epidermal Stem Cells and Is Required for Skin Tumorigenesis

    PubMed Central

    Okumura, Kazuhiro; Saito, Megumi; Isogai, Eriko; Aoto, Yoshimasa; Hachiya, Tsuyoshi; Sakakibara, Yasubumi; Katsuragi, Yoshinori; Hirose, Satoshi; Kominami, Ryo; Goitsuka, Ryo; Nakamura, Takuro; Wakabayashi, Yuichi

    2014-01-01

    Previous studies have shown that Meis1 plays an important role in blood development and vascular homeostasis, and can induce blood cancers, such as leukemia. However, its role in epithelia remains largely unknown. Here, we uncover two roles for Meis1 in the epidermis: as a critical regulator of epidermal homeostasis in normal tissues and as a proto-oncogenic factor in neoplastic tissues. In normal epidermis, we show that Meis1 is predominantly expressed in the bulge region of the hair follicles where multipotent adult stem cells reside, and that the number of these stem cells is reduced when Meis1 is deleted in the epidermal tissue of mice. Mice with epidermal deletion of Meis1 developed significantly fewer DMBA/TPA-induced benign and malignant tumors compared with wild-type mice, suggesting that Meis1 plays a role in both tumor development and malignant progression. This is consistent with the observation that Meis1 expression increases as tumors progress from benign papillomas to malignant carcinomas. Interestingly, we found that Meis1 localization was altered to neoplasia development. Instead of being localized to the stem cell region, Meis1 is localized to more differentiated cells in tumor tissues. These findings suggest that, during the transformation from normal to neoplastic tissues, a functional switch occurs in Meis1. PMID:25013928

  10. Progenitor Cell Mobilization by Gamma-tocotrienol: A Promising Radiation Countermeasure

    PubMed Central

    Singh, Vijay K.; Fatanmi, Oluseyi O.; Verma, Amit; Newman, Victoria L.; Wise, Stephen Y.; Romaine, Patricia L.P.; Berg, Allison N.

    2016-01-01

    Abstract This article reviews studies of progenitor mobilization with gamma-tocotrienol (GT3), a tocol under advanced development as a radiation countermeasure for acute radiation syndrome (ARS). GT3 protects mice against high doses of ionizing radiation and induces high levels of granulocyte colony-stimulating factor (G-CSF). GT3‐induced G-CSF in conjunction with AMD3100 (a chemokine receptor antagonist clinically used to improve the yield of mobilized progenitors) mobilizes progenitors; these mobilized progenitors mitigate injury when infused to mice exposed to acute, high-dose ionizing radiation. The administration of a G-CSF antibody to GT3‐injected donor mice abrogated the radiomitigative efficacy of blood or peripheral blood mononuclear cells (PBMC) in irradiated recipient mice. The efficacy of GT3‐injected donor mice blood or PBMC was comparable to a recently published article involving blood or mononuclear cells obtained from mice injected with G-CSF. The injected progenitors were found to localize in various tissues of irradiated hosts. The authors demonstrate the efficacy of a bridging therapy in a preclinical animal model that allows the lymphohematopoietic system of severely immunocompromised mice to recover. This suggests that GT3 is a highly effective agent for radioprotection and mobilizing progenitors with significant therapeutic potential. Therefore, GT3 may be considered for further translational development and ultimately for use in humans. PMID:27356050

  11. Progenitor Cell Mobilization by Gamma-tocotrienol: A Promising Radiation Countermeasure.

    PubMed

    Singh, Vijay K; Fatanmi, Oluseyi O; Verma, Amit; Newman, Victoria L; Wise, Stephen Y; Romaine, Patricia L P; Berg, Allison N

    2016-08-01

    This article reviews studies of progenitor mobilization with gamma-tocotrienol (GT3), a tocol under advanced development as a radiation countermeasure for acute radiation syndrome (ARS). GT3 protects mice against high doses of ionizing radiation and induces high levels of granulocyte colony-stimulating factor (G-CSF). GT3-induced G-CSF in conjunction with AMD3100 (a chemokine receptor antagonist clinically used to improve the yield of mobilized progenitors) mobilizes progenitors; these mobilized progenitors mitigate injury when infused to mice exposed to acute, high-dose ionizing radiation. The administration of a G-CSF antibody to GT3-injected donor mice abrogated the radiomitigative efficacy of blood or peripheral blood mononuclear cells (PBMC) in irradiated recipient mice. The efficacy of GT3-injected donor mice blood or PBMC was comparable to a recently published article involving blood or mononuclear cells obtained from mice injected with G-CSF. The injected progenitors were found to localize in various tissues of irradiated hosts. The authors demonstrate the efficacy of a bridging therapy in a preclinical animal model that allows the lymphohematopoietic system of severely immunocompromised mice to recover. This suggests that GT3 is a highly effective agent for radioprotection and mobilizing progenitors with significant therapeutic potential. Therefore, GT3 may be considered for further translational development and ultimately for use in humans. PMID:27356050

  12. Epidermal cells are the primary phagocytes in the fragmentation and clearance of degenerating dendrites in Drosophila

    PubMed Central

    Xiao, Hui; Wang, Denan; Franc, Nathalie C.; Jan, Lily Yeh; Jan, Yuh-Nung

    2014-01-01

    SUMMARY During developmental remodeling, neurites destined for pruning often degenerate on-site. Physical injury also induces degeneration of neurites distal to the injury site. Prompt clearance of degenerating neurites is important for maintaining tissue homeostasis and preventing inflammatory responses. Here we show that in both dendrite pruning and dendrite injury of Drosophila sensory neurons, epidermal cells rather than hemocytes are the primary phagocytes in clearing degenerating dendrites. Epidermal cells act via Draper-mediated recognition to facilitate dendrite degeneration and to engulf and degrade degenerating dendrites. Using multiple dendritic membrane markers to trace phagocytosis, we show that two members of the CD36 family, croquemort (crq) and debris buster (dsb), act at distinct stages of phagosome maturation for dendrite clearance. Our finding reveals the physiological importance of coordination between neurons and their surrounding epidermis, for both dendrite fragmentation and clearance. PMID:24412417

  13. Generation of Stratified Squamous Epithelial Progenitor Cells from Mouse Induced Pluripotent Stem Cells

    PubMed Central

    Yoshida, Satoru; Yasuda, Miyuki; Miyashita, Hideyuki; Ogawa, Yoko; Yoshida, Tetsu; Matsuzaki, Yumi; Tsubota, Kazuo; Okano, Hideyuki; Shimmura, Shigeto

    2011-01-01

    Background Application of induced pluripotent stem (iPS) cells in regenerative medicine will bypass ethical issues associated with use of embryonic stem cells. In addition, patient-specific IPS cells can be useful to elucidate the pathophysiology of genetic disorders, drug screening, and tailor-made medicine. However, in order to apply iPS cells to mitotic tissue, induction of tissue stem cells that give rise to progeny of the target organ is required. Methodology/Principal Findings We induced stratified epithelial cells from mouse iPS cells by co-culture with PA6 feeder cells (SDIA-method) with use of BMP4. Clusters of cells positive for the differentiation markers KRT1 or KRT12 were observed in KRT14-positive colonies. We successfully cloned KRT14 and p63 double-positive stratified epithelial progenitor cells from iPS-derived epithelial cells, which formed stratified epithelial sheets consisting of five- to six-polarized epithelial cells in vitro. When these clonal cells were cultured on denuded mouse corneas, a robust stratified epithelial layer was observed with physiological cell polarity including high levels of E-cadherin, p63 and K15 expression in the basal layer and ZO-1 in the superficial layer, recapitulating the apico-basal polarity of the epithelium in vivo. Conclusions/Significance These results suggest that KRT14 and p63 double-positive epithelial progenitor cells can be cloned from iPS cells in order to produce polarized multilayer epithelial cell sheets. PMID:22174914

  14. Effects of topical pimecrolimus 1% on high-dose ultraviolet B-irradiated epidermal Langerhans cells.

    PubMed

    Yin, ZhiQiang; Xu, JiaLi; Zhang, ZhiHong; Luo, Dan

    2012-12-01

    Some studies reported no changes in the number of epidermal Langerhans cells (LC) that were observed in mice treated with pimecrolimus, and low-dose stimulated solar radiation (once)-induced changers in LC are minimally affected by pimecrolimus. This study is to investigate the effects of topical pimecrolimus 1% on high-dose ultraviolet B (UVB)-irradiated epidermal LC. Forty human foreskin tissues were randomly divided into 4 groups of 10 tissues each: Group A, control; Group B, pimecrolimus 1% (once)-only; Group C, 180 mJ/cm(2) UVB (once)-only; Group D, UVB+pimecrolimus. Each tissue was cut into 4 pieces corresponding to 4 time points. All the tissues were cultured at 37 °C. After being treated, the tissues were collected respectively and processed for immunohistochemical staining and immunofluorescence staining. For UVB-only group, epidermal CD1a(+) LC number at 18h decreased from 39.6 ± 8.30 to 22.3 ± 2.26/5 high magnification, compared to CD1a(+) LC number at 0 h (P<0.01). The CD1a(+) LC number of UVB-only group was significantly less than other groups at 18 h, 24h and 48 h (P<0.05, respectively). Similar results were obtained with immunofluorescence staining for CD 1a and immunohistochemical staining for Langerin. The numbers of epidermal HLA-DR(+) LC had no significant differences among all groups at different time points. Our study found a single 180 mJ/cm(2) UVB irradiation significantly reduced epidermal LC numbers at 18 h, 24h and 48 h, however, topical pimecrolimus could reverse these changes. UVB plus pimecrolimus treatment did not affect human LC maturation. PMID:23079131

  15. Skin Stem Cells: At the Frontier Between the Laboratory and Clinical Practice. Part 1: Epidermal Stem Cells.

    PubMed

    Pastushenko, I; Prieto-Torres, L; Gilaberte, Y; Blanpain, C

    2015-11-01

    Stem cells are characterized by their ability to self-renew and differentiate into the different cell lineages of their tissue of origin. The discovery of stem cells in adult tissues, together with the description of specific markers for their isolation, has opened up new lines of investigation, expanding the horizons of biomedical research and raising new hope in the treatment of many diseases. In this article, we review in detail the main characteristics of the stem cells that produce the specialized cells of the skin (epidermal, mesenchymal, and melanocyte stem cells) and their potential implications and applications in diseases affecting the skin. Part I deals with the principal characteristics and potential applications of epidermal stem cells in dermatology. PMID:26189363

  16. The EBF transcription factor Collier directly promotes Drosophila blood cell progenitor maintenance independently of the niche

    PubMed Central

    Benmimoun, Billel; Polesello, Cédric; Haenlin, Marc; Waltzer, Lucas

    2015-01-01

    The maintenance of stem or progenitor cell fate relies on intrinsic factors as well as local cues from the cellular microenvironment and systemic signaling. In the lymph gland, an hematopoietic organ in Drosophila larva, a group of cells called the Posterior Signaling Centre (PSC), whose specification depends on the EBF transcription factor Collier (Col) and the HOX factor Antennapedia (Antp), has been proposed to form a niche required to maintain the pool of hematopoietic progenitors (prohemocytes). In contrast with this model, we show here that genetic ablation of the PSC does not cause an increase in blood cell differentiation or a loss of blood cell progenitors. Furthermore, although both col and Antp mutant larvae are devoid of PSC, the massive prohemocyte differentiation observed in col mutant is not phenocopied in Antp mutant. Interestingly, beside its expression in the PSC, Col is also expressed at low levels in prohemocytes and we show that this expression persists in PSC-ablated and Antp mutant larvae. Moreover, targeted knockdown and rescue experiments indicate that Col expression is required in the prohemocytes to prevent their differentiation. Together, our findings show that the PSC is dispensable for blood cell progenitor maintenance and reveal the key role of the conserved transcription factor Col as an intrinsic regulator of hematopoietic progenitor fate. PMID:26150488

  17. Nucleic Acid Encoding A Lectin-Derived Progenitor Cell Preservation Factor

    DOEpatents

    Colucci, M. Gabriella; Chrispeels, Maarten J.; Moore, Jeffrey G.

    2001-10-30

    The invention relates to an isolated nucleic acid molecule that encodes a protein that is effective to preserve progenitor cells, such as hematopoietic progenitor cells. The nucleic acid comprises a sequence defined by SEQ ID NO:1, a homolog thereof, or a fragment thereof. The encoded protein has an amino acid sequence that comprises a sequence defined by SEQ ID NO:2, a homolog thereof, or a fragment thereof that contains an amino acid sequence TNNVLQVT. Methods of using the encoded protein for preserving progenitor cells in vitro, ex vivo, and in vivo are also described. The invention, therefore, include methods such as myeloablation therapies for cancer treatment wherein myeloid reconstitution is facilitated by means of the specified protein. Other therapeutic utilities are also enabled through the invention, for example, expanding progenitor cell populations ex vivo to increase chances of engraftation, improving conditions for transporting and storing progenitor cells, and facilitating gene therapy to treat and cure a broad range of life-threatening hematologic diseases.

  18. Dextran induces differentiation of circulating endothelial progenitor cells

    PubMed Central

    Obi, Syotaro; Masuda, Haruchika; Akimaru, Hiroshi; Shizuno, Tomoko; Yamamoto, Kimiko; Ando, Joji; Asahara, Takayuki

    2014-01-01

    Abstract Endothelial progenitor cells (EPCs) have been demonstrated to be effective for the treatment of cardiovascular diseases. However, the differentiation process from circulation to adhesion has not been clarified because circulating EPCs rarely attached to dishes in EPC cultures previously. Here we investigated whether immature circulating EPCs differentiate into mature adhesive EPCs in response to dextran. When floating‐circulating EPCs derived from ex vivo expanded human cord blood were cultured with 5% and 10% dextran, they attached to fibronectin‐coated dishes and grew exponentially. The bioactivities of adhesion, proliferation, migration, tube formation, and differentiated type of EPC colony formation increased in EPCs exposed to dextran. The surface protein expression rate of the endothelial markers vascular endothelial growth factor (VEGF)‐R1/2, VE‐cadherin, Tie2, ICAM1, VCAM1, and integrin αv/β3 increased in EPCs exposed to dextran. The mRNA levels of VEGF‐R1/2, VE‐cadherin, Tie2, endothelial nitric oxide synthase, MMP9, and VEGF increased in EPCs treated with dextran. Those of endothelium‐related transcription factors ID1/2, FOXM1, HEY1, SMAD1, FOSL1, NFkB1, NRF2, HIF1A, EPAS1 increased in dextran‐treated EPCs; however, those of hematopoietic‐ and antiangiogenic‐related transcription factors TAL1, RUNX1, c‐MYB, GATA1/2, ERG, FOXH1, HHEX, SMAD2/3 decreased in dextran‐exposed EPCs. Inhibitor analysis showed that PI3K/Akt, ERK1/2, JNK, and p38 signal transduction pathways are involved in the differentiation in response to dextran. In conclusion, dextran induces differentiation of circulating EPCs in terms of adhesion, migration, proliferation, and vasculogenesis. The differentiation mechanism in response to dextran is regulated by multiple signal transductions including PI3K/Akt, ERK1/2, JNK, and p38. These findings indicate that dextran is an effective treatment for EPCs in regenerative medicines. PMID:24760515

  19. Epidermal growth factor receptor in non-small cell lung cancer

    PubMed Central

    2015-01-01

    Following the identification of a group of patients in the initial tyrosine kinase inhibitor (TKI) trials for lung cancer, there has been detailed focus on which patients may benefit from inhibitor therapy. This article reviews the background, genetics and prevalence of epidermal growth factor mutations in non-small cell lung cancer (NSCLC). Additionally, the prevalence in unselected patients is compared against various other reviews. PMID:25870793

  20. Oestrogen signalling in white adipose progenitor cells inhibits differentiation into brown adipose and smooth muscle cells.

    PubMed

    Lapid, Kfir; Lim, Ajin; Clegg, Deborah J; Zeve, Daniel; Graff, Jonathan M

    2014-01-01

    Oestrogen, often via oestrogen receptor alpha (ERα) signalling, regulates metabolic physiology, highlighted by post-menopausal temperature dysregulation (hot flashes), glucose intolerance, increased appetite and reduced metabolic rate. Here we show that ERα signalling has a role in adipose lineage specification in mice. ERα regulates adipose progenitor identity and potency, promoting white adipogenic lineage commitment. White adipose progenitors lacking ERα reprogramme and enter into smooth muscle and brown adipogenic fates. Mechanistic studies highlight a TGFβ programme involved in progenitor reprogramming downstream of ERα signalling. The observed reprogramming has profound metabolic outcomes; both female and male adipose-lineage ERα-mutant mice are lean, have improved glucose sensitivity and are resistant to weight gain on a high-fat diet. Further, they are hypermetabolic, hyperphagic and hyperthermic, all consistent with a brown phenotype. Together, these findings indicate that ERα cell autonomously regulates adipose lineage commitment, brown fat and smooth muscle cell formation, and systemic metabolism, in a manner relevant to prevalent metabolic diseases. PMID:25330806

  1. Oestrogen signalling in white adipose progenitor cells inhibits differentiation into brown adipose and smooth muscle cells

    PubMed Central

    Clegg, Deborah J.; Zeve, Daniel; Graff, Jonathan M.

    2016-01-01

    Oestrogen, often via oestrogen receptor alpha (ERα) signalling, regulates metabolic physiology, highlighted by post-menopausal temperature dysregulation (hot flashes), glucose intolerance, increased appetite and reduced metabolic rate. Here we show that ERα signalling has a role in adipose lineage specification in mice. ERα regulates adipose progenitor identity and potency, promoting white adipogenic lineage commitment. White adipose progenitors lacking ERα reprogramme and enter into smooth muscle and brown adipogenic fates. Mechanistic studies highlight a TGFβ programme involved in progenitor reprogramming downstream of ERα signalling. The observed reprogramming has profound metabolic outcomes; both female and male adipose-lineage ERα-mutant mice are lean, have improved glucose sensitivity and are resistant to weight gain on a high-fat diet. Further, they are hypermetabolic, hyperphagic and hyperthermic, all consistent with a brown phenotype. Together, these findings indicate that ERα cell autonomously regulates adipose lineage commitment, brown fat and smooth muscle cell formation, and systemic metabolism, in a manner relevant to prevalent metabolic diseases. PMID:25330806

  2. A Novel Selectable Islet 1 Positive Progenitor Cell Reprogrammed to Expandable and Functional Smooth Muscle Cells.

    PubMed

    Turner, Elizabeth C; Huang, Chien-Ling; Sawhney, Neha; Govindarajan, Kalaimathi; Clover, Anthony J P; Martin, Kenneth; Browne, Tara C; Whelan, Derek; Kumar, Arun H S; Mackrill, John J; Wang, Shaohua; Schmeckpeper, Jeffrey; Stocca, Alessia; Pierce, William G; Leblond, Anne-Laure; Cai, Liquan; O'Sullivan, Donnchadh M; Buneker, Chirlei K; Choi, Janet; MacSharry, John; Ikeda, Yasuhiro; Russell, Stephen J; Caplice, Noel M

    2016-05-01

    Disorders affecting smooth muscle structure/function may require technologies that can generate large scale, differentiated and contractile smooth muscle cells (SMC) suitable for cell therapy. To date no clonal precursor population that provides large numbers of differentiated SMC in culture has been identified in a rodent. Identification of such cells may also enhance insight into progenitor cell fate decisions and the relationship between smooth muscle precursors and disease states that implicate differentiated SMC.  In this study, we used classic clonal expansion techniques to identify novel self-renewing Islet 1 (Isl-1) positive primitive progenitor cells (PPC) within rat bone marrow that exhibited canonical stem cell markers and preferential differentiation towards a smooth muscle-like fate. We subsequently used molecular tagging to select Isl-1 positive clonal populations from expanded and de novo marrow cell populations. We refer to these previously undescribed cells as the PPC given its stem cell marker profile, and robust self-renewal capacity. PPC could be directly converted into induced smooth muscle cells (iSMC) using single transcription factor (Kruppel-like factor 4) knockdown or transactivator (myocardin) overexpression in contrast to three control cells (HEK 293, endothelial cells and mesenchymal stem cells) where such induction was not possible. iSMC exhibited immuno- and cytoskeletal-phenotype, calcium signaling profile and contractile responses similar to bona fide SMC. Passaged iSMC could be expanded to a scale sufficient for large scale tissue replacement.  PPC and reprogramed iSMC so derived may offer future opportunities to investigate molecular, structure/function and cell-based replacement therapy approaches to diverse cardiovascular, respiratory, gastrointestinal, and genitourinary diseases that have as their basis smooth muscle cell functional aberrancy or numerical loss. Stem Cells 2016;34:1354-1368. PMID:26840832

  3. Progenitors of skeletal muscle satellite cells express the muscle determination gene, MyoD

    PubMed Central

    Kanisicak, Onur; Mendez, Julio J.; Yamamoto, Shoko; Yamamoto, Masakazu; Goldhamer, David J.

    2009-01-01

    Satellite cells are tissue-specific stem cells responsible for skeletal muscle growth and regeneration. Although satellite cells were identified almost 50 years ago, the identity of progenitor populations from which they derive remains controversial. We developed MyoDiCre knockin mice, and used Cre/lox lineage analysis to determine whether satellite cell progenitors express MyoD, a marker of myogenic commitment. Recombination status of satellite cells was determined by confocal microscopy of isolated muscle fibers and by electron microscopic observation of muscle tissue fixed immediately following isolation, using R26R-EYFP and R26R (β-gal) reporter mice, respectively. We show that essentially all adult satellite cells associated with limb and body wall musculature, as well as the diaphragm and extraocular muscles, originate from MyoD+ progenitors. Neonatal satellite cells were Cre-recombined, but only a small minority exhibited ongoing Cre expression, indicating that most satellite cells had expressed MyoD prenatally. We also show that satellite cell development in MyoD-null mice is not due to functional compensation by MyoD non-expressing lineages. The results suggest that satellite cells are derived from committed myogenic progenitors, irrespective of the anatomical location, embryological origin, or physiological properties of associated musculature. PMID:19464281

  4. Human primordial germ cell-derived progenitors give rise to neurons and glia in vivo

    SciTech Connect

    Teng, Yincheng; Chen, Bin; Tao, Minfang

    2009-12-18

    We derived a cell population from cultured human primordial germ cells from early human embryos. The derivates, termed embryoid body-derived (EBD) cells, displayed an extensive capacity for proliferation and expressed a panel of markers in all three germ layers. Interestingly, EBD cells were also positive for markers of neural stem/progenitor cells, such as nestin and glial fibrillary acidic protein. When these cells were transplanted into the brain cavities of fetal sheep and postnatal NOD-SCID mice or nerve-degenerated tibialis anterior muscles, they readily gave rise to neurons or glial cells. To our knowledge, our data are the first to demonstrate that EBD cells can undergo further neurogenesis under suitable environments in vivo. Hence, with the abilities of extensive expansion, self-renewal, and differentiation, EBD cells may provide a useful donor source for neural stem/progenitor cells to be used in cell-replacement therapies for diseases of the nervous system.

  5. Acquisition of granule neuron precursor identity is a critical determinant of progenitor cell competence to form Hedgehog-induced medulloblastoma

    PubMed Central

    Schüller, Ulrich; Heine, Vivi M.; Mao, Junhao; Kho, Alvin T.; Dillon, Allison K.; Han, Young-Goo; Huillard, Emmanuelle; Sun, Tao; Ligon, Azra H.; Qian, Ying; Ma, Qiufu; Alvarez-Buylla, Arturo; McMahon, Andrew P.; Rowitch, David H.; Ligon, Keith L.

    2008-01-01

    Origins of the brain tumor, medulloblastoma, from stem cells or restricted progenitor cells are unclear. To investigate this, we activated oncogenic Hedgehog (Hh) signaling in multipotent and lineage-restricted CNS progenitors. We observed that normal unipotent cerebellar granule neuron precursors (CGNP) derive from hGFAP+ and Olig2+ RL progenitors. Hh activation in a spectrum of early and late stage CNS progenitors generated similar medulloblastomas, but not other brain cancers, indicating that acquisition of CGNP identity is essential for tumorigenesis. We show in human and mouse medulloblastoma that cells expressing the glia-associated markers Gfap and Olig2 are neoplastic and that they retain features of embryonic-type granule lineage progenitors. Thus, oncogenic Hh signaling promotes medulloblastoma from lineage-restricted granule cell progenitors. PMID:18691547

  6. Differentiation of pancreatic stem and progenitor β-cells into insulin secreting cells in mice with diabetes mellitus.

    PubMed

    Skurikhin, E G; Ermakova, N N; Khmelevskaya, E S; Pershina, O V; Krupin, V A; Ermolaeva, L A; Dygai, A M

    2014-04-01

    We studied in vitro differentiation of pancreatic stem and progenitor cells into insulin secreting cells in the model of streptozotocin-induced diabetes in C57Bl/6 mice. Streptozotocin was shown to increase the population of pancreatic oligopotent β-cell precursors (CD45(-), TER119(-), CD133(+), and CD49f(low)) and did not affect multipotent (stem) progenitor cells (CD45(-), TER119(-), CD17(-), CD309(-)). During long-term culturing, diabetic multipotent progenitor cells showed high capacity for self-renewal. A population of dithizone-positive (insulin secreting cells) mononuclear cells was obtained releasing insulin after prolonged culturing in suspension enriched with diabetic CD45(-), TER119(-), CD17(-), and CD309(-) cells. The rate of generation of "new" insulin-producing cells and insulin release in the samples of experimental group considerably exceeded activity of the corresponding processes in the control group. PMID:24824681

  7. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus.

    PubMed

    Zhu, Fei-Bin; Fang, Xiang-Jing; Liu, De-Wu; Shao, Ying; Zhang, Hong-Yan; Peng, Yan; Zhong, Qing-Ling; Li, Yong-Tie; Liu, De-Ming

    2016-03-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 days. With prolonged time, type I collagen content gradually increased, yet type III collagen content gradually diminished. Abundant protein gene product 9.5- and substance P-immunoreactive nerve fibers regenerated. Partial nerve fiber endings extended to the epidermis. The therapeutic effects of combined substance P and epidermal stem cells were better than with amniotic membrane and either factor alone. Our results suggest that the combination of substance P and epidermal stem cells effectively contributes to nerve regeneration and wound healing in diabetic rats. PMID:27127492

  8. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus

    PubMed Central

    Zhu, Fei-bin; Fang, Xiang-jing; Liu, De-wu; Shao, Ying; Zhang, Hong-yan; Peng, Yan; Zhong, Qing-ling; Li, Yong-tie; Liu, De-ming

    2016-01-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 days. With prolonged time, type I collagen content gradually increased, yet type III collagen content gradually diminished. Abundant protein gene product 9.5- and substance P-immunoreactive nerve fibers regenerated. Partial nerve fiber endings extended to the epidermis. The therapeutic effects of combined substance P and epidermal stem cells were better than with amniotic membrane and either factor alone. Our results suggest that the combination of substance P and epidermal stem cells effectively contributes to nerve regeneration and wound healing in diabetic rats. PMID:27127492

  9. A sensitive electrochemiluminescence cytosensor for quantitative evaluation of epidermal growth factor receptor expressed on cell surfaces.

    PubMed

    Tang, Yanjuan; Zhang, Shaolian; Wen, Qingqing; Huang, Hongxing; Yang, Peihui

    2015-06-30

    A sensitive electrochemiluminescence (ECL) strategy for evaluating the epidermal growth factor receptor (EGFR) expression level on cell surfaces was designed by integrating the specific recognition of EGFR expressed on MCF-7 cell surfaces with an epidermal growth factor (EGF)-funtionalized CdS quantum dots (CdSQDs)-capped magnetic bead (MB) probe. The high sensitivity of ECL probe of EGF-funtionalized CdSQD-capped-MB was used for competitive recognition with EGFR expressed on cell surfaces with recombinant EGFR protein. The changes of ECL intensity depended on both the cell number and the expression level of EGFR receptor on cell surfaces. A wide linear response to cells ranging from 80 to 4×10(6)cellsmL(-1) with a detection limit of 40cellsmL(-1) was obtained. The EGF-cytosensor was used to evaluate EGFR expression levels on MCF-7 cells, and the average number of EGFR receptor on single MCF-7 cells was 1.35×10(5) with the relative standard deviation of 4.3%. This strategy was further used for in-situ and real-time evaluating EGFR receptor expressed on cell surfaces in response to drugs stimulation at different concentration and incubation time. The proposed method provided potential applications in the detection of receptors on cancer cells and anticancer drugs screening. PMID:26041531

  10. Alterations of circulating lymphoid committed progenitor cellular metabolism after allogeneic stem cell transplantation in humans.

    PubMed

    Glauzy, Salomé; Peffault de Latour, Régis; André-Schmutz, Isabelle; Lachuer, Joël; Servais, Sophie; Socié, Gérard; Clave, Emmanuel; Toubert, Antoine

    2016-09-01

    Lymphoid-committed CD34(+)lin(-)CD10(+)CD24(-) progenitors undergo a rebound at month 3 after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the absence of acute graft-versus-host disease (aGVHD). Here, we analyzed transcriptional programs of cell-sorted circulating lymphoid-committed progenitors and CD34(+)Lin(-)CD10(-) nonlymphoid progenitors in 11 allo-HSCT patients who had (n = 5) or had not (n = 6) developed grade 2 or 3 aGVHD and in 7 age-matched healthy donors. Major upregulated pathways include protein synthesis, energy production, cell cycle regulation, and cytoskeleton organization. Notably, genes from protein biogenesis, translation machinery, and cell cycle (CDK6) were overexpressed in progenitors from patients in the absence of aGVHD compared with healthy donors and patients affected by aGVHD. Expression of many genes from the mitochondrial oxidative phosphorylation metabolic pathway leading to ATP production were more specifically increased in lymphoid-committed progenitors in the absence of aGVHD. This was also the case for genes involved in cell mobilization such as those regulating Rho GTPase activity. In all, we found that circulating lymphoid-committed progenitors undergo profound changes in metabolism, favoring cell proliferation, energy production, and cell mobilization after allo-HSCT in humans. These mechanisms are abolished in the case of aGVHD or its treatment, indicating a persistent cell-intrinsic defect after exit from the bone marrow. PMID:27321893

  11. Bifurcation dynamics and determination of alternate cell fates in bipotent progenitor cells.

    PubMed

    Li, Shanshan; Liu, Yanwei; Liu, Zengrong; Wang, Ruiqi

    2015-04-01

    The gene regulatory networks in which two lineage-affiliated transcription factors, such as GATA1 and PU.1, inhibit each other but activate themselves so as to regulate the choice between alternative cell fates have been extensively studied. These simple networks can generate bistability and explain the transitions between the alternative cell fates. The commitment of a progenitor cell to a new fate corresponds to the occurrence of different types of bifurcations, depending on if a system is symmetrical and how perturbations affect the system. Here we take a general modeling and analyzing approach and show that the lateral inhibition with symmetry and asymmetry can lead to different bifurcation dynamics. Especially, if cell fate decision-making is initiated with asymmetry or symmetry-breaking perturbations, a progenitor cell pre-patterns itself into a polarized cell, depending on the asymmetry or symmetry-breaking perturbations. This study may help us understand the fundamental features of binary cell fate decisions more clearly and further apply to a wider range of decision-making processes. PMID:25852780

  12. Transient inactivation of Notch signaling synchronizes differentiation of neural progenitor cells

    PubMed Central

    Nelson, Branden R.; Hartman, Byron H.; Georgi, Sean A.; Lan, Michael S.; Reh, Thomas A.

    2007-01-01

    Summary In the developing nervous system, the balance between proliferation and differentiation is critical to generate the appropriate numbers and types of neurons and glia. Notch signaling maintains the progenitor pool throughout this process. While many components of the Notch pathway have been identified, the downstream molecular events leading to neural differentiation are not well understood. We have taken advantage of a small molecule inhibitor, DAPT, to block Notch activity in retinal progenitor cells, and analyzed the resulting molecular and cellular changes over time. DAPT treatment causes a massive, coordinated differentiation of progenitors that produces cell types appropriate for their developmental stage. Transient exposure of retina to DAPT for specific time periods allowed us to define the period of Notch inactivation that is required for a permanent commitment to differentiate. Inactivation of Notch signaling revealed a cascade of proneural bHLH transcription factor gene expression that correlates with stages in progenitor cell differentiation. Microarray/QPCR analysis confirms the changes in Notch signaling components, and reveals new molecular targets for investigating neuronal differentiation. Thus, transient inactivation of Notch signaling synchronizes progenitor cell differentiation, and allows for a systematic analysis of key steps in this process. PMID:17280659

  13. S-phase duration is the main target of cell cycle regulation in neural progenitors of developing ferret neocortex.

    PubMed

    Turrero García, Miguel; Chang, YoonJeung; Arai, Yoko; Huttner, Wieland B

    2016-02-15

    The evolutionary expansion of the neocortex primarily reflects increases in abundance and proliferative capacity of cortical progenitors and in the length of the neurogenic period during development. Cell cycle parameters of neocortical progenitors are an important determinant of cortical development. The ferret (Mustela putorius furo), a gyrencephalic mammal, has gained increasing importance as a model for studying corticogenesis. Here, we have studied the abundance, proliferation, and cell cycle parameters of different neural progenitor types, defined by their differential expression of the transcription factors Pax6 and Tbr2, in the various germinal zones of developing ferret neocortex. We focused our analyses on postnatal day 1, a late stage of cortical neurogenesis when upper-layer neurons are produced. Based on cumulative 5-ethynyl-2'-deoxyuridine (EdU) labeling as well as Ki67 and proliferating cell nuclear antigen (PCNA) immunofluorescence, we determined the duration of the various cell cycle phases of the different neocortical progenitor subpopulations. Ferret neocortical progenitors were found to exhibit longer cell cycles than those of rodents and little variation in the duration of G1 among distinct progenitor types, also in contrast to rodents. Remarkably, the main difference in cell cycle parameters among the various progenitor types was the duration of S-phase, which became shorter as progenitors progressively changed transcription factor expression from patterns characteristic of self-renewal to those of neuron production. Hence, S-phase duration emerges as major target of cell cycle regulation in cortical progenitors of this gyrencephalic mammal. PMID:25963823

  14. Isolation, Culture, and Characterization of Chicken Cartilage Stem/Progenitor Cells

    PubMed Central

    Li, Lu; Ma, Yuehui; Li, Xianglong; Li, Xiangchen; Bai, Chunyu; Ji, Meng; Zhang, Shuang; Guan, Weijun; Li, Junjie

    2015-01-01

    A chondrocyte progenitor population isolated from the surface zone of articular cartilage has become a promising cell source for cell-based cartilage repair. The cartilage-derived stem/progenitor cells are multipotent stem cells, which can differentiate into three cell types in vitro including adipocytes, osteoblasts, and chondrocytes. Much work has been done on cartilage stem/progenitor cells (CSPCs) from people, horses, and cattle, but the relatively little literature has been published about these cells in chickens. In our work, CSPCs were isolated from chicken embryos in incubated eggs for 20 days. In order to inquire into the biological characteristics of chicken CSPCs, immunofluorescence, reverse transcription-polymerase chain reaction (RT-PCR), and flow cytometry were adopted to detect the characteristic surface markers of CSPCs. Primary CSPCs were subcultured to passage 22 and, for purpose of knowing the change of cell numbers, we drew the growth curves. Isolated CSPCs were induced to adipocytes, osteoblasts, and chondrocytes. Our results suggest that we have identified and characterised a novel cartilage progenitor population resident in chicken articular cartilage and CSPCs isolated from chickens possess similar biological characteristics to those from other species, which will greatly benefit future cell-based cartilage repair therapies. PMID:26351636

  15. Restricted differentiation potential of progenitor cell populations obtained from the equine superficial digital flexor tendon (SDFT)

    PubMed Central

    Humphreys, William James Edward; Comerford, Eithne Josephine Veronica; Clegg, Peter David; Canty‐Laird, Elizabeth Gail

    2015-01-01

    ABSTRACT The aim of this study was to characterize stem and progenitor cell populations from the equine superficial digital flexor tendon, an energy‐storing tendon with similarities to the human Achilles tendon, which is frequently injured. Using published methods for the isolation of tendon‐derived stem/progenitor cells by low‐density plating we found that isolated cells possessed clonogenicity but were unable to fully differentiate towards mesenchymal lineages using trilineage differentiation assays. In particular, adipogenic differentiation appeared to be restricted, as assessed by Oil Red O staining of stem/progenitor cells cultured in adipogenic medium. We then assessed whether differential adhesion to fibronectin substrates could be used to isolate a population of cells with broader differentiation potential. However we found little difference in the stem and tenogenic gene expression profile of these cells as compared to tenocytes, although the expression of thrombospondin‐4 was significantly reduced in hypoxic conditions. Tendon‐derived stem/progenitor cells isolated by differential adhesion to fibronectin had a similar differentiation potential to cells isolated by low density plating, and when grown in either normoxic or hypoxic conditions. In summary, we have found a restricted differentiation potential of cells isolated from the equine superficial digital flexor tendon despite evidence for stem/progenitor‐like characteristics. © 2015 The Authors. Journal of Orthopaedic Research Published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 33:849–858, 2015. PMID:25877997

  16. Isolation, Culture, and Characterization of Chicken Cartilage Stem/Progenitor Cells.

    PubMed

    Li, Lu; Ma, Yuehui; Li, Xianglong; Li, Xiangchen; Bai, Chunyu; Ji, Meng; Zhang, Shuang; Guan, Weijun; Li, Junjie

    2015-01-01

    A chondrocyte progenitor population isolated from the surface zone of articular cartilage has become a promising cell source for cell-based cartilage repair. The cartilage-derived stem/progenitor cells are multipotent stem cells, which can differentiate into three cell types in vitro including adipocytes, osteoblasts, and chondrocytes. Much work has been done on cartilage stem/progenitor cells (CSPCs) from people, horses, and cattle, but the relatively little literature has been published about these cells in chickens. In our work, CSPCs were isolated from chicken embryos in incubated eggs for 20 days. In order to inquire into the biological characteristics of chicken CSPCs, immunofluorescence, reverse transcription-polymerase chain reaction (RT-PCR), and flow cytometry were adopted to detect the characteristic surface markers of CSPCs. Primary CSPCs were subcultured to passage 22 and, for purpose of knowing the change of cell numbers, we drew the growth curves. Isolated CSPCs were induced to adipocytes, osteoblasts, and chondrocytes. Our results suggest that we have identified and characterised a novel cartilage progenitor population resident in chicken articular cartilage and CSPCs isolated from chickens possess similar biological characteristics to those from other species, which will greatly benefit future cell-based cartilage repair therapies. PMID:26351636

  17. Stem and progenitor cell division kinetics during postnatal mouse mammary gland development.

    PubMed

    Giraddi, Rajshekhar R; Shehata, Mona; Gallardo, Mercedes; Blasco, Maria A; Simons, Benjamin D; Stingl, John

    2015-01-01

    The cycling properties of mammary stem and progenitor cells is not well understood. To determine the division properties of these cells, we administered synthetic nucleosides for varying periods of time to mice at different stages of postnatal development and monitored the rate of uptake of these nucleosides in the different mammary cell compartments. Here we show that most cell division in the adult virgin gland is restricted to the oestrogen receptor-expressing luminal cell lineage. Our data also demonstrate that the oestrogen receptor-expressing, milk and basal cell subpopulations have telomere lengths and cell division kinetics that are not compatible with these cells being hierarchically organized; instead, our data indicate that in the adult homeostatic gland, each cell type is largely maintained by its own restricted progenitors. We also observe that transplantable stem cells are largely quiescent during oestrus, but are cycling during dioestrus when progesterone levels are high. PMID:26511661

  18. Asymmetric growth of root epidermal cells is related to the differentiation of root hair cells in Hordeum vulgare (L.)

    PubMed Central

    Marzec, Marek

    2013-01-01

    The root epidermis of most vascular plants harbours two cell types, namely trichoblasts (capable of producing a root hair) and atrichoblasts. Here, in vivo analysis, confocal laser-scanning microscopy, transmission electron microscopy, histological analysis, and three-dimensional reconstruction were used to characterize the cell types present in the barley root epidermis and their distribution in the tissue. Both trichoblasts and atrichoblasts were present in the wild-type cultivars and could be distinguished from one another at an early stage. Trichoblast/atrichoblast differentiation depended on asymmetric cell expansion after a period of symmetrical cell division. After asymmetric growth, only the shorter epidermal cells could produce root hairs, whereas the longer cells became atrichoblasts. Moreover, the root epidermis did not develop root hairs at all if the epidermal cells did not differentiate into two asymmetric cell types. The root hairless phenotype of bald root barley (brb) and root hairless 1.b (rhl1.b) mutants was caused by a mutation in a gene related to the asymmetric expansion of the root epidermal cells. Additionally, the results showed that the mechanism of trichoblast/atrichoblast differentiation is not evolutionally conserved across the subfamilies of the Poaceae; in the Pooideae subfamily, both asymmetric division and asymmetric cell expansion have been observed. PMID:24043851

  19. Effects of epidermal growth factor on neural crest cells in tissue culture

    SciTech Connect

    Erickson, C.A.; Turley, E.A.

    1987-04-01

    Epidermal growth factor (EGF) stimulates the release of hyaluronic acid (HA) and chondroitin sulfate proteoglycan (CSPG) from quail trunk neural crest cultures in a dose-dependent fashion. It also promotes the expression of cell-associated heparan sulfate proteoglycan (HSPG) as detected by immunofluorescence and immunoprecipitation of the /sup 3/H-labeled proteoglycan. Furthermore, EGF stimulates (/sup 3/H)thymidine incorporation into total cell DNA. These results raise the possibility that EGF or an analogous growth factor is involved in regulation of neural crest cell morphogenesis.

  20. Analysis of the Contribution of Nonresident Progenitor Cells and Hematopoietic Cells to Reparative Dentinogenesis Using Parabiosis Model in Mice

    PubMed Central

    Frozoni, Marcos; Zaia, Alexandre Augusto; Line, Sergio Roberto Peres; Mina, Mina

    2013-01-01

    Introduction The aim of this study was to analyze the contribution of nonresident progenitor/stem cells and hematopoietic cells to reparative dentinogenesis. Methods Parabiosis was established between C57BL/6-TgN(ACTbEGFP)10sb/J transgenic mice (GFP+) and C57BL/6 wild-type mice (GFP−) to ensure blood cross-circulation between animals. Reparative dentinogenesis was stimulated by pulp exposures and capping on the first maxillary molar in the GFP− mice. Histologic sections of injured molars from GFP− mice were analyzed by epifluorescence microscopy to examine the contributions of GFP+ cells (nonresident progenitor cells and hematopoietic cells originating from GFP+ mice) to reparative dentinogenesis. Results GFP+ cells were detected in close association with reparative dentin formed at the site of pulp exposure in the maxillary first molars of the GFP− mice. Conclusions The present study suggests the participation of the nonresident progenitor cells and hematopoietic cells in reparative dentinogenesis. PMID:22892738

  1. Estrogen regulates luminal progenitor cell differentiation through H19 gene expression

    PubMed Central

    Basak, Pratima; Chatterjee, Sumanta; Weger, Steven; Bruce, M Christine; Murphy, Leigh C; Raouf, Afshin

    2015-01-01

    Although the role of estrogen signaling in breast cancer development has been extensively studied, the mechanisms that regulate the indispensable role of estrogen in normal mammary gland development have not been well studied. Because of the unavailability of culture system to maintain estrogen-receptor-positive (ERα+) cells in vitro, the molecular mechanisms that regulate estrogen/ERα signaling in the normal human breast are unknown. In the present study, we examined the effects of estrogen signaling on ERα+ human luminal progenitors using a modified matrigel assay and found that estrogen signaling increased the expansion potential of these progenitors. Furthermore, we found that blocking ERα attenuated luminal progenitor expansion and decreased the luminal colony-forming potential of these progenitors. Additionally, blocking ERα decreased H19 expression in the luminal progenitors and led to the development of smaller luminal colonies. We further showed that knocking down the H19 gene in the luminal progenitors significantly decreased the colony-forming potential of the luminal progenitors, and this phenotype could not be rescued by the addition of estrogen. Lastly, we explored the clinical relevance of the estrogen–H19 signaling axis in breast tumors and found that ERα+ tumors exhibited a higher expression of H19 as compared with ERα− tumors and that H19 expression showed a positive correlation with ERα expression in those tumors. Taken together, the present results indicate that the estrogen–ERα–H19 signaling axis plays a role in regulating the proliferation and differentiation potentials of the normal luminal progenitors and that this signaling network may also be important in the development of ER+ breast cancer tumors. PMID:25944846

  2. Mesenchymal Stem Cell Therapy Stimulates Endogenous Host Progenitor Cells to Improve Colonic Epithelial Regeneration

    PubMed Central

    Sémont, Alexandra; Demarquay, Christelle; Bessout, Raphaëlle; Durand, Christelle; Benderitter, Marc; Mathieu, Noëlle

    2013-01-01

    Patients who undergo pelvic radiotherapy may develop severe and chronic complications resulting from gastrointestinal alterations. The lack of curative treatment highlights the importance of novel and effective therapeutic strategies. We thus tested the therapeutic benefit of mesenchymal stem cells (MSC) treatment and proposed molecular mechanisms of action. MSC efficacy was tested in an experimental model of radiation-induced severe colonic ulceration histologically similar to that observed in patients. In this model, MSC from bone marrow were administered intravenously, immediately or three weeks (established lesions) after irradiation. MSC therapy reduces radiation-induced colonic ulceration and increases animal survival. MSC treatment induces therapeutic efficacy whatever the time of cell infusion. Infused-MSC engraft in the colon but also increase endogenous MSC mobilization in blood that have lasting benefits over time. In vitro analysis demonstrates that the MSC effect is mediated by paracrine mechanisms through the non-canonical WNT (Wingless integration site) pathway. In irradiated rat colons, MSC treatment increases the expression of the non-canonical WNT4 ligand by epithelial cells. The epithelial regenerative process is improved after MSC injection by stimulation of colonic epithelial cells positive for SOX9 (SRY-box containing gene 9) progenitor/stem cell markers. This study demonstrates that MSC treatment induces stimulation of endogenous host progenitor cells to improve the regenerative process and constitutes an initial approach to arguing in favor of the use of MSC to limit/reduce colorectal damage induced by radiation. PMID:23922953

  3. Discovery of progenitor cell signatures by time-series synexpression analysis during Drosophila embryonic cell immortalization

    PubMed Central

    Dequéant, Mary-Lee; Fagegaltier, Delphine; Hu, Yanhui; Spirohn, Kerstin; Simcox, Amanda; Hannon, Gregory J.; Perrimon, Norbert

    2015-01-01

    The use of time series profiling to identify groups of functionally related genes (synexpression groups) is a powerful approach for the discovery of gene function. Here we apply this strategy during RasV12 immortalization of Drosophila embryonic cells, a phenomenon not well characterized. Using high-resolution transcriptional time-series datasets, we generated a gene network based on temporal expression profile similarities. This analysis revealed that common immortalized cells are related to adult muscle precursors (AMPs), a stem cell-like population contributing to adult muscles and sharing properties with vertebrate satellite cells. Remarkably, the immortalized cells retained the capacity for myogenic differentiation when treated with the steroid hormone ecdysone. Further, we validated in vivo the transcription factor CG9650, the ortholog of mammalian Bcl11a/b, as a regulator of AMP proliferation predicted by our analysis. Our study demonstrates the power of time series synexpression analysis to characterize Drosophila embryonic progenitor lines and identify stem/progenitor cell regulators. PMID:26438832

  4. Effects of Substrate and Co-Culture on Neural Progenitor Cell Differentiation

    SciTech Connect

    Jones, Erin Boote

    2008-01-01

    In recent years the study of stem and progenitor cells has moved to the forefront of research. Since the isolation of human hematopoietic stem cells in 1988 and the subsequent discovery of a self renewing population of multipotent cells in many tissues, many researchers have envisioned a better understanding of development and potential clinical usage in intractable diseases. Both these goals, however, depend on a solid understanding of the intracellular and extracellular forces that cause stem cells to differentiate to a specific cell fate. Many diseases of large scale cell loss have been suggested as candidates for stem cell based treatments. It is proposed that replacing the function of the damaged or defective cells by specific differentiation of stem or progenitor cells could treat the disease. Before cells can be directed to specific lineages, the mechanisms of differentiation must be better understood. Differentiation in vivo is an intensively complex system that is difficult to study. The goal of this research is to develop further understanding of the effects of soluble and extracellular matrix (ECM) cues on the differentiation of neural progenitor cells with the use of a simplified in vitro culture system. Specific research objectives are to study the differentiation of neural progenitor cells in response to astrocyte conditioned medium and protein substrate composition and concentration. In an effort to reveal the mechanism of the conditioned medium interaction, a test for the presence of a feedback loop between progenitor cells and astrocytes is presented along with an examination of conditioned medium storage temperature, which can reveal enzymatic dependencies. An examination of protein substrate composition and concentration will help to reveal the role of any ECM interactions on differentiation. This thesis is organized into a literature review covering recent advances in use of external modulators of differentiation such as surface coatings, co

  5. Mechanisms of Chemical Cooperative Carcinogenesis by Epidermal Langerhans Cells

    PubMed Central

    Lewis, Julia M.; Bürgler, Christina D.; Fraser, Juliet A.; Liao, Haihui; Golubets, Kseniya; Kucher, Cynthia L.; Zhao, Peter Y.; Filler, Renata B.; Tigelaar, Robert E.; Girardi, Michael

    2014-01-01

    Cutaneous squamous cell carcinoma (SCC) is the most prevalent invasive malignancy with metastatic potential. The epidermis is exposed to a variety of environmental DNA-damaging chemicals, principal among which are polyaromatic hydrocarbons (PAH) ubiquitous in the environment, tobacco smoke, and broiled meats. Langerhans cells (LC) comprise a network of dendritic cells situated adjacent to basal, suprabasal, and follicular infundibular keratinocytes that when mutated can give rise to SCC, and LC-intact mice are markedly more susceptible than LC-deficient mice to chemical carcinogenesis provoked by initiation with the model PAH, 7,12-dimethylbenz[a]anthracene (DMBA). LC rapidly internalize and depot DMBA as numerous membrane-independent cytoplasmic foci. Repopulation of LC-deficient mice using fetal liver LC-precursors restores DMBA-induced tumor susceptibility. LC expression of p450 enzyme CYP1B1 is required for maximal rapid induction of DNA-damage within adjacent keratinocytes and their efficient neoplastic transformation; however, effects of tumor progression also attributable to the presence of LC were revealed as CYP1B1-independent. Thus, LC make multifaceted contributions to cutaneous carcinogenesis, including via the handling and metabolism of chemical mutagens. Such findings suggest a cooperative carcinogenesis role for myeloid-derived cells resident within cancer susceptible epithelial tissues principally by influencing early events in malignant transformation. PMID:25233073

  6. Regenerative medicine: Hepatic progenitor cells up their game in the therapeutic stakes.

    PubMed

    Alison, Malcolm R; Lin, Wey-Ran

    2015-11-01

    Bipotential hepatic progenitor cells (HPCs) are recognized as making modest contributions to hepatocyte regeneration, though never credited with major liver repopulation. A new study in mice demonstrates HPCs can make a massive contribution to hepatocyte replacement, suggesting HPCs have the potential to be an effective cell therapy for liver failure. PMID:26441248

  7. Mammalian Par3 regulates progenitor cell asymmetric division via Notch signaling in the developing neocortex

    PubMed Central

    Bultje, Ronald S.; Castaneda-Castellanos, David R.; Jan, Lily Yeh; Jan, Yuh-Nung; Kriegstein, Arnold R.; Shi, Song-Hai

    2009-01-01

    Asymmetric cell division of radial glial progenitors produces neurons while allowing self-renewal; however, little is known about the mechanism that generates asymmetry in daughter cell fate specification. Here we found that mammalian partition defective protein 3 (mPar3), a key cell polarity determinant, exhibits dynamic distribution in radial glial progenitors. While it is enriched at the lateral membrane domain in the ventricular endfeet during interphase, mPar3 becomes dispersed and shows asymmetric localization as cell cycle progresses. Either removal or ectopic expression of mPar3 prevents radial glial progenitors from dividing asymmetrically yet generates different outcomes in daughter cell fate specification. Furthermore, the expression level of mPar3 affects Notch signaling, and manipulations of Notch signaling or Numb expression suppress mPar3 regulation of radial glial cell division and daughter cell fate specification. These results reveal a critical molecular pathway underlying asymmetric cell division of radial glial progenitors in the mammalian neocortex. PMID:19640478

  8. Control of AC133/CD133 and impact on human hematopoietic progenitor cells through nucleolin.

    PubMed

    Bhatia, S; Reister, S; Mahotka, C; Meisel, R; Borkhardt, A; Grinstein, E

    2015-11-01

    AC133 is a prominent surface marker of CD34+ and CD34- hematopoietic stem/progenitor cell (HSPC) subsets. AC133+ HSPCs contain high progenitor cell activity and are capable of hematopoietic reconstitution. Furthermore, AC133 is used for prospective isolation of tumor-initiating cells in several hematological malignancies. Nucleolin is a multifunctional factor of growing and cancer cells, which is aberrantly active in certain hematological neoplasms, and serves as a candidate molecular target for cancer therapy. Nucleolin is involved in gene transcription and RNA metabolism and is prevalently expressed in HSPCs, as opposed to differentiated hematopoietic tissue. The present study dissects nucleolin-mediated activation of surface AC133 and its cognate gene CD133, via specific interaction of nucleolin with the tissue-dependent CD133 promoter P1, as a mechanism that crucially contributes to AC133 expression in CD34+ HSPCs. In mobilized peripheral blood (MPB)-derived HSPCs, nucleolin elevates colony-forming unit (CFU) frequencies and enriches granulocyte-macrophage CFUs. Furthermore, nucleolin amplifies long-term culture-initiating cells and also promotes long-term, cytokine-dependent maintenance of hematopoietic progenitor cells. Active β-catenin, active Akt and Bcl-2 levels in MPB-derived HSPCs are nucleolin-dependent, and effects of nucleolin on these cells partially rely on β-catenin activity. The study provides new insights into molecular network relevant to stem/progenitor cells in normal and malignant hematopoiesis. PMID:26183533

  9. Corrective transduction of human epidermal stem cells in laminin-5-dependent junctional epidermolysis bullosa.

    PubMed

    Dellambra, E; Vailly, J; Pellegrini, G; Bondanza, S; Golisano, O; Macchia, C; Zambruno, G; Meneguzzi, G; De Luca, M

    1998-06-10

    Laminin-5 is composed of three distinct polypeptides, alpha3, beta3, and gamma2, which are encoded by three different genes, LAMA3, LAMB3, and LAMC2, respectively. We have isolated epidermal keratinocytes from a patient presenting with a lethal form of junctional epidermolysis bullosa characterized by a homozygous mutation of the LAMB3 gene, which led to complete absence of the beta3 polypeptide. In vitro, beta3-null keratinocytes were unable to synthesize laminin-5 and to assemble hemidesmosomes, maintained the impairment of their adhesive properties, and displayed a decrease of their colony-forming ability. A retroviral construct expressing a human beta3 cDNA was used to transduce primary beta3-null keratinocytes. Clonogenic beta3-null keratinocytes were transduced with an efficiency of 100%. Beta3-transduced keratinocytes were able to synthesize and secrete mature heterotrimeric laminin-5. Gene correction fully restored the keratinocyte adhesion machinery, including the capacity of proper hemidesmosomal assembly, and prevented the loss of the colony-forming ability, suggesting a direct link between adhesion to laminin-5 and keratinocyte proliferative capacity. Clonal analysis demonstrated that holoclones expressed the transgene permanently, suggesting stable correction of epidermal stem cells. Because cultured keratinocytes are used routinely to make autologous grafts for patients suffering from large skin or mucosal defects, the full phenotypic reversion of primary human epidermal stem cells defective for a structural protein opens new perspectives in the long-term treatment of genodermatoses. PMID:9650620

  10. Cofactors of LIM Domains Associate with Estrogen Receptor α to Regulate the Expression of Noncoding RNA H19 and Corneal Epithelial Progenitor Cell Function.

    PubMed

    Klein, Rachel Herndon; Stephens, Denise N; Ho, Hsiang; Chen, Jefferson K; Salmans, Michael L; Wang, Winnie; Yu, Zhengquan; Andersen, Bogi

    2016-06-17

    Cofactors of LIM domain proteins, CLIM1 and CLIM2, are widely expressed transcriptional cofactors that are recruited to gene regulatory regions by DNA-binding proteins, including LIM domain transcription factors. In the cornea, epithelium-specific expression of a dominant negative (DN) CLIM under the keratin 14 (K14) promoter causes blistering, wounding, inflammation, epithelial hyperplasia, and neovascularization followed by epithelial thinning and subsequent epidermal-like differentiation of the corneal epithelium. The defects in corneal epithelial differentiation and cell fate determination suggest that CLIM may regulate corneal progenitor cells and the transition to differentiation. Consistent with this notion, the K14-DN-Clim corneal epithelium first exhibits increased proliferation followed by fewer progenitor cells with decreased proliferative potential. In vivo ChIP-sequencing experiments with corneal epithelium show that CLIM binds to and regulates numerous genes involved in cell adhesion and proliferation, including limbally enriched genes. Intriguingly, CLIM associates primarily with non-LIM homeodomain motifs in corneal epithelial cells, including that of estrogen receptor α. Among CLIM targets is the noncoding RNA H19 whose deregulation is associated with Silver-Russell and Beckwith-Wiedemann syndromes. We demonstrate here that H19 negatively regulates corneal epithelial proliferation. In addition to cell cycle regulators, H19 affects the expression of multiple cell adhesion genes. CLIM interacts with estrogen receptor α at the H19 locus, potentially explaining the higher expression of H19 in female than male corneas. Together, our results demonstrate an important role for CLIM in regulating the proliferative potential of corneal epithelial progenitors and identify CLIM downstream target H19 as a regulator of corneal epithelial proliferation and adhesion. PMID:27129775

  11. Specific bone cells produce DLL4 to generate thymus-seeding progenitors from bone marrow

    PubMed Central

    Yu, Vionnie W.C.; Saez, Borja; Cook, Colleen; Lotinun, Sutada; Pardo-Saganta, Ana; Wang, Ying-Hua; Lymperi, Stefania; Ferraro, Francesca; Raaijmakers, Marc H.G.P.; Wu, Joy Y.; Zhou, Lan; Rajagopal, Jayaraj; Kronenberg, Henry M.; Baron, Roland

    2015-01-01

    Production of the cells that ultimately populate the thymus to generate α/β T cells has been controversial, and their molecular drivers remain undefined. Here, we report that specific deletion of bone-producing osteocalcin (Ocn)-expressing cells in vivo markedly reduces T-competent progenitors and thymus-homing receptor expression among bone marrow hematopoietic cells. Decreased intrathymic T cell precursors and decreased generation of mature T cells occurred despite normal thymic function. The Notch ligand DLL4 is abundantly expressed on bone marrow Ocn+ cells, and selective depletion of DLL4 from these cells recapitulated the thymopoietic abnormality. These data indicate that specific mesenchymal cells in bone marrow provide key molecular drivers enforcing thymus-seeding progenitor generation and thereby directly link skeletal biology to the production of T cell–based adaptive immunity. PMID:25918341

  12. Identification and characterization of a non-satellite cell muscle resident progenitor during postnatal development.

    PubMed

    Mitchell, Kathryn J; Pannérec, Alice; Cadot, Bruno; Parlakian, Ara; Besson, Vanessa; Gomes, Edgar R; Marazzi, Giovanna; Sassoon, David A

    2010-03-01

    Satellite cells are resident myogenic progenitors in postnatal skeletal muscle involved in muscle postnatal growth and adult regenerative capacity. Here, we identify and describe a population of muscle-resident stem cells, which are located in the interstitium, that express the cell stress mediator PW1 but do not express other markers of muscle stem cells such as Pax7. PW1(+)/Pax7(-) interstitial cells (PICs) are myogenic in vitro and efficiently contribute to skeletal muscle regeneration in vivo as well as generating satellite cells and PICs. Whereas Pax7 mutant satellite cells show robust myogenic potential, Pax7 mutant PICs are unable to participate in myogenesis and accumulate during postnatal growth. Furthermore, we found that PICs are not derived from a satellite cell lineage. Taken together, our findings uncover a new and anatomically identifiable population of muscle progenitors and define a key role for Pax7 in a non-satellite cell population during postnatal muscle growth. PMID:20118923

  13. Effect of microtubule-associated protein-4 on epidermal cell migration under different oxygen concentrations.

    PubMed

    Chen, Xin; Zhou, Xin; Mao, Tong-Chun; Shi, Xiao-Hua; Fan, Dong-Li; Zhang, Yi-Ming

    2016-06-01

    After skin trauma, regional epidermal cell migration mediates the re-epithelialization of the wound surface, which is an important step for wound healing, yet the underlying molecular regulatory mechanism is unclear. In the current study, HaCaT cells were maintained under different oxygen concentrations (1%, 21%, 40% and 65%). Technologies including immunofluorescence staining, wound scratch, transwell invasion, western blot and low-expression lentiviral vector were utilized to observe the changes in microtubule dynamics and the microtubule-associated protein (MAP)4 expression. MAP4's effect on cell migration under different oxygen concentrations was also studied. The results showed that under hyperoxic (40% and 65%) and hypoxic (1%) conditions, HaCaT cells were able to regulate cell microtubule dynamics by MAP4, thus promoting cell migration. On the other hand, MAP4 silencing through targeted shRNA attenuated HaCaT cell migration under the above oxygen concentrations. These results imply that MAP4 plays an important role in epidermal cell migration under different oxygen concentrations. PMID:26602869

  14. 12-Deoxyphorbols Promote Adult Neurogenesis by Inducing Neural Progenitor Cell Proliferation via PKC Activation

    PubMed Central

    Geribaldi-Doldán, Noelia; Flores-Giubi, Eugenia; Murillo-Carretero, Maribel; García-Bernal, Francisco; Carrasco, Manuel; Macías-Sánchez, Antonio J.; Domínguez-Riscart, Jesús; Verástegui, Cristina; Hernández-Galán, Rosario

    2016-01-01

    Background: Neuropsychiatric and neurological disorders frequently occur after brain insults associated with neuronal loss. Strategies aimed to facilitate neuronal renewal by promoting neurogenesis constitute a promising therapeutic option to treat neuronal death-associated disorders. In the adult brain, generation of new neurons occurs physiologically throughout the entire life controlled by extracellular molecules coupled to intracellular signaling cascades. Proteins participating in these cascades within neurogenic regions constitute potential pharmacological targets to promote neuronal regeneration of injured areas of the central nervous system. Methodology: We have performed in vitro and in vivo approaches to determine neural progenitor cell proliferation to understand whether activation of kinases of the protein kinase C family facilitates neurogenesis in the adult brain. Results: We have demonstrated that protein kinase C activation by phorbol-12-myristate-13-acetate induces neural progenitor cell proliferation in vitro. We also show that the nontumorogenic protein kinase C activator prostratin exerts a proliferative effect on neural progenitor cells in vitro. This effect can be reverted by addition of the protein kinase C inhibitor G06850, demonstrating that the effect of prostratin is mediated by protein kinase C activation. Additionally, we show that prostratin treatment in vivo induces proliferation of neural progenitor cells within the dentate gyrus of the hippocampus and the subventricular zone. Finally, we describe a library of diterpenes with a 12-deoxyphorbol structure similar to that of prostratin that induces a stronger effect than prostratin on neural progenitor cell proliferation both in vitro and in vivo. Conclusions: This work suggests that protein kinase C activation is a promising strategy to expand the endogenous neural progenitor cell population to promote neurogenesis and highlights the potential of 12-deoxyphorbols as pharmaceutical

  15. An insulin signaling feedback loop regulates pancreas progenitor cell differentiation during islet development and regeneration.