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Sample records for adult germ-line stem

  1. Transgenic mice produced by retroviral transduction of male germ-line stem cells

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    Nagano, Makoto; Brinster, Clayton J.; Orwig, Kyle E.; Ryu, Buom-Yong; Avarbock, Mary R.; Brinster, Ralph L.

    2001-01-01

    Male germ-line stem cells are the only cell type in postnatal mammals that have the capability to self-renew and to contribute genes to the next generation. Genetic modification of these cells would provide an opportunity to study the biology of their complex self-renewal and differentiation processes, as well as enable the generation of transgenic animals in a wide range of species. Although retroviral vectors have been used as an efficient method to introduce genes into a variety of cell ty...

  2. Differentiation in Stem Cell Lineages and in Life: Explorations in the Male Germ Line Stem Cell Lineage.

    Science.gov (United States)

    Fuller, Margaret T

    2016-01-01

    I have been privileged to work on cellular differentiation during a great surge of discovery that has revealed the molecular mechanisms and genetic regulatory circuitry that control embryonic development and adult tissue maintenance and repair. Studying the regulation of proliferation and differentiation in the male germ line stem cell lineage has allowed us investigate how the developmental program imposes layers of additional controls on fundamental cellular processes like cell cycle progression and gene expression to give rise to the huge variety of specialized cell types in our bodies. We are beginning to understand how local signals from somatic support cells specify self-renewal versus differentiation in the stem cell niche at the apical tip of the testis. We are discovering the molecular events that block cell proliferation and initiate terminal differentiation at the switch from mitosis to meiosis-a signature event of the germ cell program. Our work is beginning to reveal how the developmental program that sets up the dramatic new cell type-specific transcription program that prepares germ cells for meiotic division and spermatid differentiation is turned on when cells become spermatocytes. I have had the privilege of working with incredible students, postdocs, and colleagues who have discovered, brainstormed, challenged, and refined our science and our ideas of how developmental pathways and cellular mechanisms work together to drive differentiation. © 2016 Elsevier Inc. All rights reserved.

  3. Intermittent Stem Cell Cycling Balances Self-Renewal and Senescence of the C. elegans Germ Line.

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    Amanda Cinquin

    2016-04-01

    Full Text Available Self-renewing organs often experience a decline in function in the course of aging. It is unclear whether chronological age or external factors control this decline, or whether it is driven by stem cell self-renewal-for example, because cycling cells exhaust their replicative capacity and become senescent. Here we assay the relationship between stem cell cycling and senescence in the Caenorhabditis elegans reproductive system, defining this senescence as the progressive decline in "reproductive capacity," i.e. in the number of progeny that can be produced until cessation of reproduction. We show that stem cell cycling diminishes remaining reproductive capacity, at least in part through the DNA damage response. Paradoxically, gonads kept under conditions that preclude reproduction keep cycling and producing cells that undergo apoptosis or are laid as unfertilized gametes, thus squandering reproductive capacity. We show that continued activity is in fact beneficial inasmuch as gonads that are active when reproduction is initiated have more sustained early progeny production. Intriguingly, continued cycling is intermittent-gonads switch between active and dormant states-and in all likelihood stochastic. Other organs face tradeoffs whereby stem cell cycling has the beneficial effect of providing freshly-differentiated cells and the detrimental effect of increasing the likelihood of cancer or senescence; stochastic stem cell cycling may allow for a subset of cells to preserve proliferative potential in old age, which may implement a strategy to deal with uncertainty as to the total amount of proliferation to be undergone over an organism's lifespan.

  4. The perfect host: a mouse host embryo facilitating more efficient germ line transmission of genetically modified embryonic stem cells.

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    Robert A Taft

    Full Text Available There is a continual need to improve efficiency in creating precise genetic modifications in mice using embryonic stem cells (ESCs. We describe a novel approach resulting in 100% germline transmission from competent injected ESCs. We developed an F1 mouse host embryo (Perfect Host, PH that selectively ablates its own germ cells via tissue-specific induction of diphtheria toxin. This approach allows competent microinjected ESCs to fully dominate the germline, eliminating competition for this critical niche in the developing and adult animal. This is in contrast to conventional methods, where competition from host germ cells results in offspring derived from host cells and ESCs, necessitating extensive breeding of chimeras and genotyping to identify germline. The germline transmission process is also complicated by variability in the actual number of ESCs that colonize the germline niche and the proportion that are germline competent. To validate the PH approach we used ESC lines derived from 129 F1, BALB/cByJ, and BTBR backgrounds as well as an iPS line. Resulting chimeric males produced 194 offspring, all paternally derived from the introduced stem cells, with no offspring being derived from the host genome. We further tested this approach using eleven genetically modified C57BL/6N ESC lines (International Knockout Mouse Consortium. ESC germline transmission was observed in 9/11 (82% lines using PH blastocysts, compared to 6/11 (55% when conventional host blastocysts were used. Furthermore, less than 35% (83/240 of mice born in the first litters from conventional chimeras were confirmed to be of ESC-origin. By comparison, 100% (137/137 of the first litter offspring of PH chimeras were confirmed as ESC-derived. Together, these data demonstrate that the PH approach increases the probability of germline transmission and speeds the generation of ESC derived animals from chimeras. Collectively, this approach reduces the time and costs inherent in the

  5. Minichromosome maintenance helicase paralog MCM9 is dispensible for DNA replication but functions in germ-line stem cells and tumor suppression.

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    Hartford, Suzanne A; Luo, Yunhai; Southard, Teresa L; Min, Irene M; Lis, John T; Schimenti, John C

    2011-10-25

    Effective DNA replication is critical to the health and reproductive success of organisms. The six MCM2-7 proteins, which form the replicative helicase, are essential for high-fidelity replication of the genome. Many eukaryotes have a divergent paralog, MCM9, that was reported to be essential for loading MCM2-7 onto replication origins in the Xenopus oocyte extract system. To address the in vivo role of mammalian MCM9, we created and analyzed the phenotypes of mice with various mutations in Mcm9 and an intronic DNA replication-related gene Asf1a. Ablation of Mcm9 was compatible with cell proliferation and mouse viability, showing that it is nonessential for MCM2-7 loading or DNA replication. Mcm9 mutants underwent p53-independent embryonic germ-cell depletion in both sexes, with males also exhibiting defective spermatogonial stem-cell renewal. MCM9-deficient cells had elevated genomic instability and defective cell cycle reentry following replication stress, and mutant animals were prone to sex-specific cancers, most notably hepatocellular carcinoma in males. The phenotypes of mutant mice and cells suggest that MCM9 evolved a specialized but nonessential role in DNA replication or replication-linked quality-control mechanisms that are especially important for germ-line stem cells, and also for tumor suppression and genome maintenance in the soma.

  6. A vector-based system for the differentiation of mouse embryonic stem cells toward germ-line cells

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    Reza Ebrahimzadeh-Vesal

    2014-08-01

    Conclusion: In this study, we demonstrated the in vitro generation of mouse embryonic stem cells to germ cells by using a backbone vector containing the fusion gene Stra8-EGFP. The Stra8 gene is a retinoic acid-responsive protein and is able to regulate meiotic initiation.

  7. Germ line mechanics – and unfinished business

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    Wessel, Gary M.

    2016-01-01

    Primordial germ cells are usually made early in the development of an organism. These are the mother of all stem cells that are necessary for propagation of the species, yet use highly diverse mechanisms between organisms. How they are specified, and when and where they form, are central to developmental biology. Using diverse organisms to study this development is illuminating for understanding the mechanics these cells use in this essential function, and for identifying the breadth of evolutionary changes that have occurred between species. This essay emphasizes how echinoderms may contribute to the patch-work quilt of our understanding of germ line formation during embryogenesis. PMID:26970000

  8. Understanding Mammalian Germ Line Development with In Vitro Models.

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    Martínez-Arroyo, Ana M; Míguez-Forján, Jose M; Remohí, Jose; Pellicer, Antonio; Medrano, Jose V

    2015-09-15

    Germ line development is crucial in organisms with sexual reproduction to complete their life cycle. In mammals, knowledge about germ line development is based mainly on the mouse model, in which genetic and epigenetic events are well described. However, little is known about how germ line development is orchestrated in humans, especially in the earliest stages. New findings derived from human in vitro models to obtain germ cells can shed light on these questions. This comprehensive review summarizes the current knowledge about mammalian germ line development, emphasizing the state of the art obtained from in vitro models for germ cell-like cell derivation. Current knowledge of the pluripotency cycle and germ cell specification has allowed different in vitro strategies to obtain germ cells with proven functionality in mouse models. Several reports during the last 10 years show that in vitro germ cell derivation with proven functionality to generate a healthy offspring is possible in mice. However, differences in the embryo development and pluripotency potential between human and mouse make it difficult to extrapolate these results. Further efforts on both human and mouse in vitro models to obtain germ cells from pluripotent stem cells may help to elucidate how human physiological events take place; therefore, therapeutic strategies can also be considered.

  9. Identification of genes expressed in the hermaphrodite germ line of C. elegans using SAGE

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    Wang, Xin; Zhao, Yongjun; Wong, Kim; Ehlers, Peter; Kohara, Yuji; Jones, Steven J; Marra, Marco A; Holt, Robert A; Moerman, Donald G; Hansen, Dave

    2009-01-01

    Background Germ cells must progress through elaborate developmental stages from an undifferentiated germ cell to a fully differentiated gamete. Some of these stages include exiting mitosis and entering meiosis, progressing through the various stages of meiotic prophase, adopting either a male (sperm) or female (oocyte) fate, and completing meiosis. Additionally, many of the factors needed to drive embryogenesis are synthesized in the germ line. To increase our understanding of the genes that might be necessary for the formation and function of the germ line, we have constructed a SAGE library from hand dissected C. elegans hermaphrodite gonads. Results We found that 4699 genes, roughly 21% of all known C. elegans genes, are expressed in the adult hermaphrodite germ line. Ribosomal genes are highly expressed in the germ line; roughly four fold above their expression levels in the soma. We further found that 1063 of the germline-expressed genes have enriched expression in the germ line as compared to the soma. A comparison of these 1063 germline-enriched genes with a similar list of genes prepared using microarrays revealed an overlap of 460 genes, mutually reinforcing the two lists. Additionally, we identified 603 germline-enriched genes, supported by in situ expression data, which were not previously identified. We also found >4 fold enrichment for RNA binding proteins in the germ line as compared to the soma. Conclusion Using multiple technological platforms provides a more complete picture of global gene expression patterns. Genes involved in RNA metabolism are expressed at a significantly higher level in the germ line than the soma, suggesting a stronger reliance on RNA metabolism for control of the expression of genes in the germ line. Additionally, the number and expression level of germ line expressed genes on the X chromosome is lower than expected based on a random distribution. PMID:19426519

  10. Identification of genes expressed in the hermaphrodite germ line of C. elegans using SAGE

    Directory of Open Access Journals (Sweden)

    Holt Robert A

    2009-05-01

    Full Text Available Abstract Background Germ cells must progress through elaborate developmental stages from an undifferentiated germ cell to a fully differentiated gamete. Some of these stages include exiting mitosis and entering meiosis, progressing through the various stages of meiotic prophase, adopting either a male (sperm or female (oocyte fate, and completing meiosis. Additionally, many of the factors needed to drive embryogenesis are synthesized in the germ line. To increase our understanding of the genes that might be necessary for the formation and function of the germ line, we have constructed a SAGE library from hand dissected C. elegans hermaphrodite gonads. Results We found that 4699 genes, roughly 21% of all known C. elegans genes, are expressed in the adult hermaphrodite germ line. Ribosomal genes are highly expressed in the germ line; roughly four fold above their expression levels in the soma. We further found that 1063 of the germline-expressed genes have enriched expression in the germ line as compared to the soma. A comparison of these 1063 germline-enriched genes with a similar list of genes prepared using microarrays revealed an overlap of 460 genes, mutually reinforcing the two lists. Additionally, we identified 603 germline-enriched genes, supported by in situ expression data, which were not previously identified. We also found >4 fold enrichment for RNA binding proteins in the germ line as compared to the soma. Conclusion Using multiple technological platforms provides a more complete picture of global gene expression patterns. Genes involved in RNA metabolism are expressed at a significantly higher level in the germ line than the soma, suggesting a stronger reliance on RNA metabolism for control of the expression of genes in the germ line. Additionally, the number and expression level of germ line expressed genes on the X chromosome is lower than expected based on a random distribution.

  11. Epigenetic reprogramming in the porcine germ line

    DEFF Research Database (Denmark)

    Matzen, Sara Maj Hyldig; Croxall, Nicola; Contreras, David A.

    2011-01-01

    BACKGROUND: Epigenetic reprogramming is critical for genome regulation during germ line development. Genome-wide demethylation in mouse primordial germ cells (PGC) is a unique reprogramming event essential for erasing epigenetic memory and preventing the transmission of epimutations to the next...... an increased proportion of cells in G2. CONCLUSIONS: Our study demonstrates that epigenetic reprogramming occurs in pig migratory and gonadal PGC, and establishes the window of time for the occurrence of these events. Reprogramming of histone H3K9me2 and H3K27me3 detected between E15-E21 precedes the dynamic...... DNA demethylation at imprinted loci and DNA repeats between E22-E42. Our findings demonstrate that major epigenetic reprogramming in the pig germ line follows the overall dynamics shown in mice, suggesting that epigenetic reprogramming of germ cells is conserved in mammals. A better understanding...

  12. Pluripotent stem cells and reprogrammed cells in farm animals.

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    Nowak-Imialek, Monika; Kues, Wilfried; Carnwath, Joseph W; Niemann, Heiner

    2011-08-01

    Pluripotent cells are unique because of their ability to differentiate into the cell lineages forming the entire organism. True pluripotent stem cells with germ line contribution have been reported for mice and rats. Human pluripotent cells share numerous features of pluripotentiality, but confirmation of their in vivo capacity for germ line contribution is impossible due to ethical and legal restrictions. Progress toward derivation of embryonic stem cells from domestic species has been made, but the derived cells were not able to produce germ line chimeras and thus are termed embryonic stem-like cells. However, domestic animals, in particular the domestic pig (Sus scrofa), are excellent large animals models, in which the clinical potential of stem cell therapies can be studied. Reprogramming technologies for somatic cells, including somatic cell nuclear transfer, cell fusion, in vitro culture in the presence of cell extracts, in vitro conversion of adult unipotent spermatogonial stem cells into germ line derived pluripotent stem cells, and transduction with reprogramming factors have been developed with the goal of obtaining pluripotent, germ line competent stem cells from domestic animals. This review summarizes the present state of the art in the derivation and maintenance of pluripotent stem cells in domestic animals.

  13. Germ line transmission of a yeast artificial chromosome spanning the murine [alpha][sub 1](I) collagen locus

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, W.M.; Dausman, J.; Beard, C.; Jaenisch, R. (Massachusetts Inst. of Technology, Cambridge (United States)); Johnson, C.; Lawrence, J.B. (Univ. of Massachusetts Medical School, Worcester (United States))

    1993-03-26

    Molecular complementation of mutant phenotypes by transgenic technology is a potentially important tool for gene identification. A technology was developed to allow the transfer of a physically intact yeast artificial chromosome (YAC) into the germ line of the mouse. A purified 150-kilobase YAC encompassing the murine gene Col1a1 was efficiently introduced into embryonic stem (ES) cells via lipofection. Chimeric founder mice were derived from two transfected ES cell clones. These chimeras transmitted the full length transgene through the germ line, generating two transgenic mouse strains. Transgene expression was visualized as nascent transcripts in interphase nuclei and quantitated by ribonuclease protection analysis. Both assays indicated that the transgene was expressed at levels comparable to the endogenous collagen gene. 32 refs., 3 figs., 1 tab.

  14. Germ-line gene therapy and the medical imperative.

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    Munson, Ronald; Davis, Lawrence H

    1992-06-01

    Somatic cell gene therapy has yielded promising results. If germ cell gene therapy can be developed, the promise is even greater: hundreds of genetic diseases might be virtually eliminated. But some claim the procedure is morally unacceptable. We thoroughly and sympathetically examine several possible reasons for this claim but find them inadequate. There is no moral reason, then, not to develop and employ germ-line gene therapy. Taking the offensive, we argue next that medicine has a prima facie moral obligation to do so.

  15. Mismatch repair deficiency does not enhance ENU mutagenesis in the zebrafish germ line.

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    Feitsma, Harma; de Bruijn, Ewart; van de Belt, Jose; Nijman, Isaac J; Cuppen, Edwin

    2008-07-01

    S(N)1-type alkylating agents such as N-ethyl-N-nitrosourea (ENU) are very potent mutagens. They act by transferring their alkyl group to DNA bases, which, upon mispairing during replication, can cause single base pair mutations in the next replication cycle. As DNA mismatch repair (MMR) proteins are involved in the recognition of alkylation damage, we hypothesized that ENU-induced mutation rates could be increased in a MMR-deficient background, which would be beneficial for mutagenesis approaches. We applied a standard ENU mutagenesis protocol to adult zebrafish deficient in the MMR gene msh6 and heterozygous controls to study the effect of MMR on ENU-induced DNA damage. Dose-dependent lethality was found to be similar for homozygous and heterozygous mutants, indicating that there is no difference in ENU resistance. Mutation discovery by high-throughput dideoxy resequencing of genomic targets in outcrossed progeny of the mutagenized fish did also not reveal any differences in germ line mutation frequency. These results may indicate that the maximum mutation load for zebrafish has been reached with the currently used, highly optimized ENU mutagenesis protocol. Alternatively, the MMR system in the zebrafish germ line may be saturated very rapidly, thereby having a limited effect on high-dose ENU mutagenesis.

  16. Germ line p53 mutations in a familial syndrome of breast cancer, sarcomas, and other neoplasms.

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    Malkin, D; Li, F P; Strong, L C; Fraumeni, J F; Nelson, C E; Kim, D H; Kassel, J; Gryka, M A; Bischoff, F Z; Tainsky, M A

    1990-11-30

    Familial cancer syndromes have helped to define the role of tumor suppressor genes in the development of cancer. The dominantly inherited Li-Fraumeni syndrome (LFS) is of particular interest because of the diversity of childhood and adult tumors that occur in affected individuals. The rarity and high mortality of LFS precluded formal linkage analysis. The alternative approach was to select the most plausible candidate gene. The tumor suppressor gene, p53, was studied because of previous indications that this gene is inactivated in the sporadic (nonfamilial) forms of most cancers that are associated with LFS. Germ line p53 mutations have been detected in all five LFS families analyzed. These mutations do not produce amounts of mutant p53 protein expected to exert a trans-dominant loss of function effect on wild-type p53 protein. The frequency of germ line p53 mutations can now be examined in additional families with LFS, and in other cancer patients and families with clinical features that might be attributed to the mutation.

  17. FLI-1 Flightless-1 and LET-60 Ras control germ line morphogenesis in C. elegans

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    Dentler William L

    2008-05-01

    Full Text Available Abstract Background In the C. elegans germ line, syncytial germ line nuclei are arranged at the cortex of the germ line as they exit mitosis and enter meiosis, forming a nucleus-free core of germ line cytoplasm called the rachis. Molecular mechanisms of rachis formation and germ line organization are not well understood. Results Mutations in the fli-1 gene disrupt rachis organization without affecting meiotic differentiation, a phenotype in C. elegans referred to here as the germ line morphogenesis (Glm phenotype. In fli-1 mutants, chains of meiotic germ nuclei spanned the rachis and were partially enveloped by invaginations of germ line plasma membrane, similar to nuclei at the cortex. Extensions of the somatic sheath cells that surround the germ line protruded deep inside the rachis and were associated with displaced nuclei in fli-1 mutants. fli-1 encodes a molecule with leucine-rich repeats and gelsolin repeats similar to Drosophila flightless 1 and human Fliih, which have been shown to act as cytoplasmic actin regulators as well as nuclear transcriptional regulators. Mutations in let-60 Ras, previously implicated in germ line development, were found to cause the Glm phenotype. Constitutively-active LET-60 partially rescued the fli-1 Glm phenotype, suggesting that LET-60 Ras and FLI-1 might act together to control germ line morphogenesis. Conclusion FLI-1 controls germ line morphogenesis and rachis organization, a process about which little is known at the molecular level. The LET-60 Ras GTPase might act with FLI-1 to control germ line morphogenesis.

  18. Expression of the Argonaute protein PiwiL2 and piRNAs in adult mouse mesenchymal stem cells

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    Wu, Qiuling; Ma, Qi; Shehadeh, Lina A.; Wilson, Amber; Xia, Linghui; Yu, Hong [Department of Molecular and Cellular Pharmacology, Vascular Biology Institute, University of Miami Miller School of Medicine, Miami, FL 33136 (United States); Webster, Keith A., E-mail: kwebster@med.miami.edu [Department of Molecular and Cellular Pharmacology, Vascular Biology Institute, University of Miami Miller School of Medicine, Miami, FL 33136 (United States)

    2010-06-11

    Piwi (P-element-induced wimpy testis) first discovered in Drosophila is a member of the Argonaute family of micro-RNA binding proteins with essential roles in germ-cell development. The murine homologue of PiwiL2, also known as Mili is selectively expressed in the testes, and mice bearing targeted mutations of the PiwiL2 gene are male-sterile. PiwiL2 proteins are thought to protect the germ line genome by suppressing retrotransposons, stabilizing heterochromatin structure, and regulating target genes during meiosis and mitosis. Here, we report that PiwiL2 and associated piRNAs (piRs) may play similar roles in adult mouse mesenchymal stem cells. We found that PiwiL2 is expressed in the cytoplasm of metaphase mesenchymal stem cells from the bone marrow of adult and aged mice. Knockdown of PiwiL2 with a specific siRNA enhanced cell proliferation, significantly increased the number of cells in G1/S and G2/M cell cycle phases and was associated with increased expression of cell cycle genes CCND1, CDK8, microtubule regulation genes, and decreased expression of tumor suppressors Cables 1, LATS, and Cxxc4. The results suggest broader roles for Piwi in genome surveillance beyond the germ line and a possible role in regulating the cell cycle of mesenchymal stem cells.

  19. Expression of the Argonaute protein PiwiL2 and piRNAs in adult mouse mesenchymal stem cells

    International Nuclear Information System (INIS)

    Wu, Qiuling; Ma, Qi; Shehadeh, Lina A.; Wilson, Amber; Xia, Linghui; Yu, Hong; Webster, Keith A.

    2010-01-01

    Piwi (P-element-induced wimpy testis) first discovered in Drosophila is a member of the Argonaute family of micro-RNA binding proteins with essential roles in germ-cell development. The murine homologue of PiwiL2, also known as Mili is selectively expressed in the testes, and mice bearing targeted mutations of the PiwiL2 gene are male-sterile. PiwiL2 proteins are thought to protect the germ line genome by suppressing retrotransposons, stabilizing heterochromatin structure, and regulating target genes during meiosis and mitosis. Here, we report that PiwiL2 and associated piRNAs (piRs) may play similar roles in adult mouse mesenchymal stem cells. We found that PiwiL2 is expressed in the cytoplasm of metaphase mesenchymal stem cells from the bone marrow of adult and aged mice. Knockdown of PiwiL2 with a specific siRNA enhanced cell proliferation, significantly increased the number of cells in G1/S and G2/M cell cycle phases and was associated with increased expression of cell cycle genes CCND1, CDK8, microtubule regulation genes, and decreased expression of tumor suppressors Cables 1, LATS, and Cxxc4. The results suggest broader roles for Piwi in genome surveillance beyond the germ line and a possible role in regulating the cell cycle of mesenchymal stem cells.

  20. Effects of chemical and physical agents on recombination events in cells of the germ line of male and female Drosophila melanogaster.

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    Würgler, F E

    1991-01-01

    Genotoxic agents can induce mutations as well as recombination in the genetic material. The fruit fly Drosophila melanogaster was one of the first assay systems to test physical and chemical agents for recombinogenic effects. Such effects can be observed in cells of the germ line as well as in somatic cells. At present information is available on 54 agents, among them 48 chemicals that have been tested in cells of the germ line of males and/or females. Effects on meiotic recombination in female germ cells cannot simply be classified as positive or negative since for a number of agents, depending on the chromosome region studied, recombination frequencies may be increased, unaffected or decreased. The male germ line of D. melanogaster represents a unique situation because meiotic recombination does not occur. Among 25 agents tested in male germ cells 24 did induce male recombination, among them alkylating, intercalating and cross-linking agents, direct-acting ones as well as compounds needing metabolic activation. With several compounds the frequency of induced recombination is highest in the heterochromatic regions near the centromeres. In brood pattern analyses, e.g., after exposure of adult males to ionizing radiation, the first appearance of crossover progeny is indicative of the sampling of exposed spermatocytes. In premeiotic cells of the male and the female germ line mitotic recombination can occur. Upon clonal expansion of the recombinant cells, clusters of identical crossovers can be observed.

  1. The ethics of germ line gene manipulation--a five dimensional debate.

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    Carter, Lucy

    2002-10-01

    Contributors to the debate surrounding the ethics of germ line gene manipulation have by and large concentrated their efforts on discussions of the potential risks that are associated with the use of this technology. Many international advisory committees have ruled out the acceptability of germ line gene manipulation at least for the time being. The purpose of this work is to generate much needed discussion on the many other ethical issues concerning the implementation of not only germ line gene manipulation but also other related biotechnologies. In this paper I systematically investigate and analyse the most salient issues put forward by proponents and opponents alike. I argue that if germ line manipulation proves to be a safe and effective procedure, then the principle of beneficence imposes on the medical profession a moral duty to pursue the technology.

  2. A germ cell determinant reveals parallel pathways for germ line development in Caenorhabditis elegans.

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    Mainpal, Rana; Nance, Jeremy; Yanowitz, Judith L

    2015-10-15

    Despite the central importance of germ cells for transmission of genetic material, our understanding of the molecular programs that control primordial germ cell (PGC) specification and differentiation are limited. Here, we present findings that X chromosome NonDisjunction factor-1 (XND-1), known for its role in regulating meiotic crossover formation, is an early determinant of germ cell fates in Caenorhabditis elegans. xnd-1 mutant embryos display a novel 'one PGC' phenotype as a result of G2 cell cycle arrest of the P4 blastomere. Larvae and adults display smaller germ lines and reduced brood size consistent with a role for XND-1 in germ cell proliferation. Maternal XND-1 proteins are found in the P4 lineage and are exclusively localized to the nucleus in PGCs, Z2 and Z3. Zygotic XND-1 turns on shortly thereafter, at the ∼300-cell stage, making XND-1 the earliest zygotically expressed gene in worm PGCs. Strikingly, a subset of xnd-1 mutants lack germ cells, a phenotype shared with nos-2, a member of the conserved Nanos family of germline determinants. We generated a nos-2 null allele and show that nos-2; xnd-1 double mutants display synthetic sterility. Further removal of nos-1 leads to almost complete sterility, with the vast majority of animals without germ cells. Sterility in xnd-1 mutants is correlated with an increase in transcriptional activation-associated histone modification and aberrant expression of somatic transgenes. Together, these data strongly suggest that xnd-1 defines a new branch for PGC development that functions redundantly with nos-2 and nos-1 to promote germline fates by maintaining transcriptional quiescence and regulating germ cell proliferation. © 2015. Published by The Company of Biologists Ltd.

  3. A landscape of germ line mutations in a cohort of inherited bone marrow failure patients.

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    Bluteau, Olivier; Sebert, Marie; Leblanc, Thierry; Peffault de Latour, Régis; Quentin, Samuel; Lainey, Elodie; Hernandez, Lucie; Dalle, Jean-Hugues; Sicre de Fontbrune, Flore; Lengline, Etienne; Itzykson, Raphael; Clappier, Emmanuelle; Boissel, Nicolas; Vasquez, Nadia; Da Costa, Mélanie; Masliah-Planchon, Julien; Cuccuini, Wendy; Raimbault, Anna; De Jaegere, Louis; Adès, Lionel; Fenaux, Pierre; Maury, Sébastien; Schmitt, Claudine; Muller, Marc; Domenech, Carine; Blin, Nicolas; Bruno, Bénédicte; Pellier, Isabelle; Hunault, Mathilde; Blanche, Stéphane; Petit, Arnaud; Leverger, Guy; Michel, Gérard; Bertrand, Yves; Baruchel, André; Socié, Gérard; Soulier, Jean

    2018-02-15

    Bone marrow (BM) failure (BMF) in children and young adults is often suspected to be inherited, but in many cases diagnosis remains uncertain. We studied a cohort of 179 patients (from 173 families) with BMF of suspected inherited origin but unresolved diagnosis after medical evaluation and Fanconi anemia exclusion. All patients had cytopenias, and 12.0% presented ≥5% BM blast cells. Median age at genetic evaluation was 11 years; 20.7% of patients were aged ≤2 years and 36.9% were ≥18 years. We analyzed genomic DNA from skin fibroblasts using whole-exome sequencing, and were able to assign a causal or likely causal germ line mutation in 86 patients (48.0%), involving a total of 28 genes. These included genes in familial hematopoietic disorders ( GATA2 , RUNX1 ), telomeropathies ( TERC , TERT , RTEL1 ), ribosome disorders ( SBDS , DNAJC21 , RPL5 ), and DNA repair deficiency ( LIG4 ). Many patients had an atypical presentation, and the mutated gene was often not clinically suspected. We also found mutations in genes seldom reported in inherited BMF (IBMF), such as SAMD9 and SAMD9L (N = 16 of the 86 patients, 18.6%), MECOM/EVI1 (N = 6, 7.0%), and ERCC6L2 (N = 7, 8.1%), each of which was associated with a distinct natural history; SAMD9 and SAMD9L patients often experienced transient aplasia and monosomy 7, whereas MECOM patients presented early-onset severe aplastic anemia, and ERCC6L2 patients, mild pancytopenia with myelodysplasia. This study broadens the molecular and clinical portrait of IBMF syndromes and sheds light on newly recognized disease entities. Using a high-throughput sequencing screen to implement precision medicine at diagnosis can improve patient management and family counseling. © 2018 by The American Society of Hematology.

  4. Germ line determinants are not localized early in sea urchin development, but do accumulate in the small micromere lineage.

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    Juliano, Celina E; Voronina, Ekaterina; Stack, Christie; Aldrich, Maryanna; Cameron, Andrew R; Wessel, Gary M

    2006-12-01

    Two distinct modes of germ line determination are used throughout the animal kingdom: conditional-an inductive mechanism, and autonomous-an inheritance of maternal factors in early development. This study identifies homologs of germ line determinants in the sea urchin Strongylocentrotus purpuratus to examine its mechanism of germ line determination. A list of conserved germ-line associated genes from diverse organisms was assembled to search the S. purpuratus genome for homologs, and the expression patterns of these genes were examined during embryogenesis by whole mount in situ RNA hybridization and QPCR. Of the 14 genes tested, all transcripts accumulate uniformly during oogenesis and Sp-pumilio, Sp-tudor, Sp-MSY, and Sp-CPEB1 transcripts are also uniformly distributed during embryonic development. Sp-nanos2, Sp-seawi, and Sp-ovo transcripts, however, are enriched in the vegetal plate of the mesenchyme blastula stage and Sp-vasa, Sp-nanos2, Sp-seawi, and Sp-SoxE transcripts are localized in small micromere descendents at the tip of the archenteron during gastrulation and are then enriched in the left coelomic pouch of larvae. The results of this screen suggest that sea urchins conditionally specify their germ line, and support the hypothesis that this mechanism is the basal mode of germ line determination amongst deuterostomes. Furthermore, accumulation of germ line determinants selectively in small micromere descendents supports the hypothesis that these cells contribute to the germ line.

  5. Spondyloepiphseal dysplasia congenita in siblings born to unaffected parents: ? germ line mosaicism

    Energy Technology Data Exchange (ETDEWEB)

    Mulla, W.; McDonald-McGinn, D.; Zackai, E. [Univ. of Pennsylvania School of Medicine, Philadelphia, PA (United States)] [and others

    1994-09-01

    Germ line mosaicism has been used to explain the birth of more than one child affected with a dominantly inherited disorder born to unaffected parents. Furthermore, it has been confirmed clinically in families where recurrence in siblings was originally thought to be autosomal recessive, but were affected individuals have reproduced affected offspring. Firm evidence of germ line mosaicism using mutation analysis by molecular methods exists for some autosomal disorders. We present two siblings with spondyloepipheseal dysplasia congenita (SEDC) born to unaffected parents. This suggests the presence of germ line mosaicism in this entity. Patient 1 was born at 32 weeks gestation to a G1P1 Puerto Rican mother. The pregnancy was complicated by polyhydramnios. The neonate, a short-limbed dwarf, died at 15 hours of age from respiratory distress and a compromised thoracic cavity. Patient 2, the sibling of patient 1 was born at 37 weeks gestation after a pregnancy complicated by polyhydramnios and prenatal ultrasound diagnosis of short-limbed dwarfism. The diagnosis of SEDC was made and, after review of the sibling`s postmortem X-rays, it was felt that she was similarly affected. The family history reveals no history of dwarfism or consanguinity. The SEDC is described as an autosomal dominant form of dwarfism with variable presentation including some cases that have been lethal in the neonatal period. SEDC is now believed to represent a family of collagen II mutations. Sporadic cases that have arisen in families with no history have been ascribed to new heterozygous mutations. Other families in which SEDC and SEMD recurred without a family history most likely represent germ line mosaicism. In these cases molecular studies should be pursued to document a collagen II mutation. We believe that germ line mosaicism is the most plausible explanation for recurrence in our family.

  6. Genetic modification of the human germ line: The reasons why this project has no future.

    Science.gov (United States)

    Morange, Michel

    2015-01-01

    Modification of the human germ line has remained a distant but valuable objective for most biologists since the emergence of genetics (and even before). To study the historical transformations of this project, I have selected three periods - the 1930s, at the pinnacle of eugenics, around 1974 when molecular biology triumphed, and today - and have adopted three criteria to estimate the feasibility of this project: the state of scientific knowledge, the existence of suitable tools, and societal demands. Although the long-awaited techniques to modify the germ line are now available, I will show that most of the expectations behind this project have disappeared, or are considered as being reachable by highly different strategies. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  7. Doubly uniparental inheritance of mitochondria as a model system for studying germ line formation.

    Directory of Open Access Journals (Sweden)

    Liliana Milani

    Full Text Available BACKGROUND: Doubly Uniparental Inheritance (DUI of mitochondria occurs when both mothers and fathers are capable of transmitting mitochondria to their offspring, in contrast to the typical Strictly Maternal Inheritance (SMI. DUI was found in some bivalve molluscs, in which two mitochondrial genomes are inherited, one through eggs, the other through sperm. During male embryo development, spermatozoon mitochondria aggregate in proximity of the first cleavage furrow and end up in the primordial germ cells, while they are dispersed in female embryos. METHODOLOGY/PRINCIPAL FINDINGS: We used MitoTracker, microtubule staining and transmission electron microscopy to examine the mechanisms of this unusual distribution of sperm mitochondria in the DUI species Ruditapes philippinarum. Our results suggest that in male embryos the midbody deriving from the mitotic spindle of the first division concurs in positioning the aggregate of sperm mitochondria. Furthermore, an immunocytochemical analysis showed that the germ line determinant Vasa segregates close to the first cleavage furrow. CONCLUSIONS/SIGNIFICANCE: In DUI male embryos, spermatozoon mitochondria aggregate in a stable area on the animal-vegetal axis: in organisms with spiral segmentation this zone is not involved in cleavage, so the aggregation is maintained. Moreover, sperm mitochondria reach the same embryonic area in which also germ plasm is transferred. In 2-blastomere embryos, the segregation of sperm mitochondria in the same region with Vasa suggests their contribution in male germ line formation. In DUI male embryos, M-type mitochondria must be recognized by egg factors to be actively transferred in the germ line, where they become dominant replacing the Balbiani body mitochondria. The typical features of germ line assembly point to a common biological mechanism shared by DUI and SMI organisms. Although the molecular dynamics of the segregation of sperm mitochondria in DUI species are unknown

  8. Sequence and expression pattern of the germ line marker vasa in honey bees and stingless bees

    Science.gov (United States)

    2009-01-01

    Queens and workers of social insects differ in the rates of egg laying. Using genomic information we determined the sequence of vasa, a highly conserved gene specific to the germ line of metazoans, for the honey bee and four stingless bees. The vasa sequence of social bees differed from that of other insects in two motifs. By RT-PCR we confirmed the germ line specificity of Amvasa expression in honey bees. In situ hybridization on ovarioles showed that Amvasa is expressed throughout the germarium, except for the transition zone beneath the terminal filament. A diffuse vasa signal was also seen in terminal filaments suggesting the presence of germ line cells. Oocytes showed elevated levels of Amvasa transcripts in the lower germarium and after follicles became segregated. In previtellogenic follicles, Amvasa transcription was detected in the trophocytes, which appear to supply its mRNA to the growing oocyte. A similar picture was obtained for ovarioles of the stingless bee Melipona quadrifasciata, except that Amvasa expression was higher in the oocytes of previtellogenic follicles. The social bees differ in this respect from Drosophila, the model system for insect oogenesis, suggesting that changes in the sequence and expression pattern of vasa may have occurred during social evolution. PMID:21637523

  9. Sequence and expression pattern of the germ line marker vasa in honey bees and stingless bees

    Directory of Open Access Journals (Sweden)

    Érica Donato Tanaka

    2009-01-01

    Full Text Available Queens and workers of social insects differ in the rates of egg laying. Using genomic information we determined the sequence of vasa, a highly conserved gene specific to the germ line of metazoans, for the honey bee and four stingless bees. The vasa sequence of social bees differed from that of other insects in two motifs. By RT-PCR we confirmed the germ line specificity of Amvasa expression in honey bees. In situ hybridization on ovarioles showed that Amvasa is expressed throughout the germarium, except for the transition zone beneath the terminal filament. A diffuse vasa signal was also seen in terminal filaments suggesting the presence of germ line cells. Oocytes showed elevated levels of Amvasa transcripts in the lower germarium and after follicles became segregated. In previtellogenic follicles, Amvasa transcription was detected in the trophocytes, which appear to supply its mRNA to the growing oocyte. A similar picture was obtained for ovarioles of the stingless bee Melipona quadrifasciata, except that Amvasa expression was higher in the oocytes of previtellogenic follicles. The social bees differ in this respect from Drosophila, the model system for insect oogenesis, suggesting that changes in the sequence and expression pattern of vasa may have occurred during social evolution.

  10. CD34+ Testicular Stromal Cells Support Long-Term Expansion of Embryonic and Adult Stem and Progenitor Cells

    Science.gov (United States)

    Kim, Jiyeon; Seandel, Marco; Falciatori, Ilaria; Wen, Duancheng; Rafii, Shahin

    2010-01-01

    Stem cells reside in specialized microenvironments created by supporting stromal cells that orchestrate self-renewal and lineage-specific differentiation. However, the precise identity of the cellular and molecular pathways that support self-renewal of stem cells is not known. For example, long-term culture of prototypical stem cells, such as adult spermatogonial stem and progenitor cells (SPCs), in vitro has been impeded by the lack of an optimal stromal cell line that initiates and sustains proliferation of these cells. Indeed, current methods, including the use of mouse embryonic fibroblasts (MEFs), have not been efficient and have generally led to inconsistent results. Here, we report the establishment of a novel CD34-positive cell line, referred to as JK1, derived from mouse testicular stromal cells that not only facilitated long-term SPC culture but also allowed faithful generation of SPCs and multipotent stem cells. SPCs generated on JK1 maintained key features of germ line stem cells, including expression of PLZF, DAZL, and GCNA. Furthermore, these feeders also promoted the long-term cultivation of other types of primitive cells including multi-potent adult spermatogonial-derived stem cells, pluripotent murine embryonic stem cells, and embryonic germ cells derived from primordial germ cells. Stem cells could be passaged serially and still maintained expression of characteristic markers such as OCT4 and NANOG in vitro, as well as the ability to generate all three germ layers in vivo. These results indicate that the JK1 cell line is capable of promoting long-term culture of primitive cells. As such, this cell line allows for identification of stromal-derived factors that support long-term proliferation of various types of stem cells and constitutes a convenient alternative to other types of feeder layers. PMID:18669907

  11. Molecular mechanisms of adult stem cell aging

    National Research Council Canada - National Science Library

    Rudolph, K. Lenhard

    2010-01-01

    "There is growing evidence that adult stem cells age. This process can result in alterations in the number and function of stem cells, leading to distinct phenotypic outcomes in different organ systems...

  12. Proliferation of endogenous retroviruses in the early stages of a host germ line invasion.

    Science.gov (United States)

    Ishida, Yasuko; Zhao, Kai; Greenwood, Alex D; Roca, Alfred L

    2015-01-01

    Endogenous retroviruses (ERVs) comprise 8% of the human genome and are common in all vertebrate genomes. The only retrovirus known to be currently transitioning from exogenous to endogenous form is the koala retrovirus (KoRV), making koalas (Phascolarctos cinereus) ideal for examining the early stages of retroviral endogenization. To distinguish endogenous from exogenous KoRV proviruses, we isolated koala genomic regions flanking KoRV integration sites. In three wild southern Australian koalas, there were fewer KoRV loci than in three captive Queensland koalas, consistent with reports that southern Australian koalas carry fewer KoRVs. Of 39 distinct KoRV proviral loci examined in a sire-dam-progeny triad, all proved to be vertically transmitted and endogenous; none was exogenous. Of the 39 endogenous KoRVs (enKoRVs), only one was present in the genomes of both the sire and the dam, suggesting that, at this early stage in the retroviral invasion of a host germ line, very large numbers of ERVs have proliferated at very low frequencies in the koala population. Sequence divergence between the 5'- and 3'-long terminal repeats (LTRs) of a provirus can be used as a molecular clock. Within each of ten enKoRVs, the 5'-LTR sequence was identical to the 3'-LTR sequence, suggesting a maximum age for enKoRV invasion of the koala germ line of approximately 22,200-49,900 years ago, although a much younger age is possible. Across the ten proviruses, seven LTR haplotypes were detected, indicating that at least seven different retroviral sequences had entered the koala germ line. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Proliferation of Endogenous Retroviruses in the Early Stages of a Host Germ Line Invasion

    Science.gov (United States)

    Ishida, Yasuko; Zhao, Kai; Greenwood, Alex D.; Roca, Alfred L.

    2015-01-01

    Endogenous retroviruses (ERVs) comprise 8% of the human genome and are common in all vertebrate genomes. The only retrovirus known to be currently transitioning from exogenous to endogenous form is the koala retrovirus (KoRV), making koalas (Phascolarctos cinereus) ideal for examining the early stages of retroviral endogenization. To distinguish endogenous from exogenous KoRV proviruses, we isolated koala genomic regions flanking KoRV integration sites. In three wild southern Australian koalas, there were fewer KoRV loci than in three captive Queensland koalas, consistent with reports that southern Australian koalas carry fewer KoRVs. Of 39 distinct KoRV proviral loci examined in a sire–dam–progeny triad, all proved to be vertically transmitted and endogenous; none was exogenous. Of the 39 endogenous KoRVs (enKoRVs), only one was present in the genomes of both the sire and the dam, suggesting that, at this early stage in the retroviral invasion of a host germ line, very large numbers of ERVs have proliferated at very low frequencies in the koala population. Sequence divergence between the 5′- and 3′-long terminal repeats (LTRs) of a provirus can be used as a molecular clock. Within each of ten enKoRVs, the 5′-LTR sequence was identical to the 3′-LTR sequence, suggesting a maximum age for enKoRV invasion of the koala germ line of approximately 22,200–49,900 years ago, although a much younger age is possible. Across the ten proviruses, seven LTR haplotypes were detected, indicating that at least seven different retroviral sequences had entered the koala germ line. PMID:25261407

  14. Therapeutic potential of adult stem cells

    DEFF Research Database (Denmark)

    Serakinci, Nedime; Keith, W. Nicol

    2006-01-01

    is the necessity to be able to identify, select, expand and manipulate cells outside the body. Recent advances in adult stem cell technologies and basic biology have accelerated therapeutic opportunities aimed at eventual clinical applications. Adult stem cells with the ability to differentiate down multiple...... lineages are an attractive alternative to human embryonic stem cells (hES) in regenerative medicine. In many countries, present legislation surrounding hES cells makes their use problematic, and indeed the origin of hES cells may represent a controversial issue for many communities. However, adult stem...... cells are not subject to these issues. This review will therefore focus on adult stem cells. Based on their extensive differentiation potential and, in some cases, the relative ease of their isolation, adult stem cells are appropriate for clinical development. Recently, several observations suggest...

  15. Germ-line origins of mutation in families with hemophilia B: The sex ratio varies with the type of mutation

    Energy Technology Data Exchange (ETDEWEB)

    Ketterling, R.P.; Vielhaber, E.; Bottema, C.D.K.; Schaid, D.J.; Sommer, S.S. (Mayo Clinic/Foundation, Rochester, MN (United States)); Cohen, M.P. (Vanderbilt Univ., Nashville, TN (United States)); Sexauer, C.L. (Children' s Hospital, Oklahoma City, OK (United States))

    1993-01-01

    Previous epidemiological and biochemical studies have generated conflicting estimates of the sex ratio of mutation. Direct genomic sequencing in combination with haplotype analysis extends previous analyses by allowing the precise mutation to be determined in a given family. From analysis of the factor IX gene of 260 consecutive families with hemophilia B, the authors report the germ-line origin of mutation in 25 families. When combined with 14 origins of mutation reported by others and with 4 origins previously reported by them, a total of 25 occur in the female germ line, and 18 occur in the male germ line. The excess of germ-line origins in females does not imply an overall excess mutation rate per base pair in the female germ line. Bayesian analysis of the data indicates that the sex ratio varies with the type of mutation. The aggregate of single-base substitutions shows a male predominance of germ-line mutations (P < .002). The maximum-likelihood estimate of the male predominance is 3.5-fold. Of the single-base substitutions, deletions display a sex ratio of unity. Analysis of the parental age at transmission of a new mutation suggests that germ-line mutations are associated with a small increase in parental age in females but little, if any, increase in males. Although direct genomic sequencing offers a general method for defining the origin of mutation in specific families, accurate estimates of the sex ratios of different mutational classes require large sample sizes and careful correction for multiple biases of ascertainment. The biases in the present data result in an underestimate of the enhancement of mutation in males. 62 refs., 1 fig., 5 tabs.

  16. Optimized gene editing technology for Drosophila melanogaster using germ line-specific Cas9.

    Science.gov (United States)

    Ren, Xingjie; Sun, Jin; Housden, Benjamin E; Hu, Yanhui; Roesel, Charles; Lin, Shuailiang; Liu, Lu-Ping; Yang, Zhihao; Mao, Decai; Sun, Lingzhu; Wu, Qujie; Ji, Jun-Yuan; Xi, Jianzhong; Mohr, Stephanie E; Xu, Jiang; Perrimon, Norbert; Ni, Jian-Quan

    2013-11-19

    The ability to engineer genomes in a specific, systematic, and cost-effective way is critical for functional genomic studies. Recent advances using the CRISPR-associated single-guide RNA system (Cas9/sgRNA) illustrate the potential of this simple system for genome engineering in a number of organisms. Here we report an effective and inexpensive method for genome DNA editing in Drosophila melanogaster whereby plasmid DNAs encoding short sgRNAs under the control of the U6b promoter are injected into transgenic flies in which Cas9 is specifically expressed in the germ line via the nanos promoter. We evaluate the off-targets associated with the method and establish a Web-based resource, along with a searchable, genome-wide database of predicted sgRNAs appropriate for genome engineering in flies. Finally, we discuss the advantages of our method in comparison with other recently published approaches.

  17. Melatonin receptor genes (mel-1a, mel-1b, mel-1c) are differentially expressed in the avian germ line.

    Science.gov (United States)

    Kawashima, Takaharu; Stepińska, Urszula; Kuwana, Takashi; Olszańska, Bozenna

    2008-09-01

    The presence of melatonin receptor transcripts (mel-1a, mel-1b and mel-1c) was investigated in primordial germ cells (PGCs), immature and mature oocytes, and sperm of Japanese quail by reverse transcription--polymerase chain reaction (RT-PCR). The mel-1a transcript was detected in as few as in a thousand PGCs. Significant differences in the expression of melatonin receptor genes were found in differentiating germ cells: in PGCs only the mel-1a receptor was expressed, in blastoderms and immature oocytes all three transcripts (mel-1a, mel-1b, mel-1c) were present, while in mature ovulated oocytes the predominant transcript was mel-1c (with sporadic occurrence of mel-1a and mel-1b). In sperm, mel-1a and mel-1c were present but mel-1b was absent. This indicates that the expression of melatonin receptor genes changes throughout the differentiation of PGCs into adult gametes: during oocyte differentiation two additional transcripts, mel-1b and mel-1c, are synthesized in addition to mel-1a, but at oocyte maturation, mel-1a and mel-1b are degraded and only mel-1c remains. During male line (spermatozoa) differentiation mel-1c is transcribed in addition to mel-1a, with mel-1b being completely absent. Since melatonin and the activities of enzymes participating in melatonin synthesis are present in the avian yolk, it is reasonable to suggest a role for this molecule in early avian development and germ line differentiation. We propose that melatonin may act as a signaling molecule regulating some differentiation processes (e.g., cell proliferation, migration, etc.) before the formation of neural and hormonal systems.

  18. Lack of GNAQ and GNA11 germ-line mutations in familial melanoma pedigrees with uveal melanoma or blue nevi

    Directory of Open Access Journals (Sweden)

    Jason Ezra Hawkes

    2013-06-01

    Full Text Available Approximately 10% of melanoma cases are familial, but only 25-40% of familial melanoma cases can be attributed to germ-line mutations in the CDKN2A - the most significant high-risk melanoma susceptibility locus identified to date. The pathogenic mutation(s in most of the remaining familial melanoma pedigrees have not yet been identified. The most common mutations in nevi and sporadic melanoma are found in BRAF and NRAS, both of which result in constitutive activation of the MAPK pathway. However, these mutations are not found in uveal melanomas or the intradermal melanocytic proliferations known as blue nevi. Rather, multiple studies report a strong association between these lesions and somatic mutations in Guanine nucleotide-binding protein G(q subunit alpha (GNAQ, Guanine nucleotide-binding protein G(q subunit alpha-11 (GNA11 and BRCA1 associated protein-1 (BAP1. Recently, germ-line mutations in BAP1, the gene encoding a tumor suppressing deubiquitinating enzyme, have been associated with predisposition to a variety of cancers including uveal melanoma, but no studies have examined the association of germ-line mutations in GNAQ and GNA11 with uveal melanoma and blue nevi. We have now done so by sequencing exon 5 of both of these genes in 13 unique familial melanoma pedigrees, members of which have had either uveal or cutaneous melanoma and/or blue nevi. Germ-line DNA from a total of 22 individuals was used for sequencing; however no deleterious mutations were detected. Nevertheless, such candidate gene studies and the discovery of novel germ-line mutations associated with an increased MM susceptibility can lead to a better understanding of the pathways involved in melanocyte transformation, formulation of risk assessment, and the development of specific drug therapies.

  19. Adult Stem Cells and Diseases of Aging

    Directory of Open Access Journals (Sweden)

    Lisa B. Boyette

    2014-01-01

    Full Text Available Preservation of adult stem cells pools is critical for maintaining tissue homeostasis into old age. Exhaustion of adult stem cell pools as a result of deranged metabolic signaling, premature senescence as a response to oncogenic insults to the somatic genome, and other causes contribute to tissue degeneration with age. Both progeria, an extreme example of early-onset aging, and heritable longevity have provided avenues to study regulation of the aging program and its impact on adult stem cell compartments. In this review, we discuss recent findings concerning the effects of aging on stem cells, contributions of stem cells to age-related pathologies, examples of signaling pathways at work in these processes, and lessons about cellular aging gleaned from the development and refinement of cellular reprogramming technologies. We highlight emerging therapeutic approaches to manipulation of key signaling pathways corrupting or exhausting adult stem cells, as well as other approaches targeted at maintaining robust stem cell pools to extend not only lifespan but healthspan.

  20. Germ-line mutations of the p53 tumor suppressor gene in patients with high risk for cancer inactivate the p53 protein.

    Science.gov (United States)

    Frebourg, T; Kassel, J; Lam, K T; Gryka, M A; Barbier, N; Andersen, T I; Børresen, A L; Friend, S H

    1992-07-15

    Germ-line mutations in the p53 tumor suppressor gene have been observed in patients with Li-Fraumeni syndrome, brain tumors, second malignancies, and breast cancers. It is unclear whether all of these mutations have inactivated p53 and thereby provide an increased risk for cancer. Therefore, it is necessary to establish the biological significance of these germ-line mutations by the functional and structural analysis of the resulting mutant p53 proteins. We analyzed the ability of seven germ-line mutant proteins observed in patients with Li-Fraumeni syndrome, second primary neoplasms, or familial breast cancer to block the growth of malignant cells and compared the structural properties of the mutant proteins to that of the wild-type protein. Six of seven missense mutations disrupted the growth inhibitory properties and structure of the wild-type protein. One germ-line mutation retained the features of the wild-type p53. Genetic analysis of the breast cancer family in which this mutation was observed indicated that this germ-line mutation was not associated with the development of cancer. These results demonstrate that germ-line p53 mutations observed in patients with Li-Fraumeni syndrome and with second malignancies have inactivated the p53 tumor suppressor gene. The inability of the germ-line p53 mutants to block the growth of malignant cells can explain why patients with these germ-line mutations have an increased risk for cancer. The observation of a functionally silent germ-line mutation indicates that, before associating a germ-line tumor suppressor gene mutation with cancer risk, it is prudent to consider its functional significance.

  1. Germ-line mutations of the p53 tumor suppressor gene in patients with high risk for cancer inactivate the p53 protein.

    Science.gov (United States)

    Frebourg, T; Kassel, J; Lam, K T; Gryka, M A; Barbier, N; Andersen, T I; Børresen, A L; Friend, S H

    1992-01-01

    Germ-line mutations in the p53 tumor suppressor gene have been observed in patients with Li-Fraumeni syndrome, brain tumors, second malignancies, and breast cancers. It is unclear whether all of these mutations have inactivated p53 and thereby provide an increased risk for cancer. Therefore, it is necessary to establish the biological significance of these germ-line mutations by the functional and structural analysis of the resulting mutant p53 proteins. We analyzed the ability of seven germ-line mutant proteins observed in patients with Li-Fraumeni syndrome, second primary neoplasms, or familial breast cancer to block the growth of malignant cells and compared the structural properties of the mutant proteins to that of the wild-type protein. Six of seven missense mutations disrupted the growth inhibitory properties and structure of the wild-type protein. One germ-line mutation retained the features of the wild-type p53. Genetic analysis of the breast cancer family in which this mutation was observed indicated that this germ-line mutation was not associated with the development of cancer. These results demonstrate that germ-line p53 mutations observed in patients with Li-Fraumeni syndrome and with second malignancies have inactivated the p53 tumor suppressor gene. The inability of the germ-line p53 mutants to block the growth of malignant cells can explain why patients with these germ-line mutations have an increased risk for cancer. The observation of a functionally silent germ-line mutation indicates that, before associating a germ-line tumor suppressor gene mutation with cancer risk, it is prudent to consider its functional significance. Images PMID:1631137

  2. Clinical grade adult stem cell banking.

    Science.gov (United States)

    Thirumala, Sreedhar; Goebel, W Scott; Woods, Erik J

    2009-07-01

    There has been a great deal of scientific interest recently generated by the potential therapeutic applications of adult stem cells in human care but there are several challenges regarding quality and safety in clinical applications and a number of these challenges relate to the processing and banking of these cells ex-vivo. As the number of clinical trials and the variety of adult cells used in regenerative therapy increases, safety remains a primary concern. This has inspired many nations to formulate guidelines and standards for the quality of stem cell collection, processing, testing, banking, packaging and distribution. Clinically applicable cryopreservation and banking of adult stem cells offers unique opportunities to advance the potential uses and widespread implementation of these cells in clinical applications. Most current cryopreservation protocols include animal serum proteins and potentially toxic cryoprotectant additives (CPAs) that prevent direct use of these cells in human therapeutic applications. Long term cryopreservation of adult stem cells under good manufacturing conditions using animal product free solutions is critical to the widespread clinical implementation of ex-vivo adult stem cell therapies. Furthermore, to avoid any potential cryoprotectant related complications, reduced CPA concentrations and efficient post-thaw washing to remove CPA are also desirable. The present review focuses on the current strategies and important aspects of adult stem cell banking for clinical applications. These include current good manufacturing practices (cGMPs), animal protein free freezing solutions, cryoprotectants, freezing & thawing protocols, viability assays, packaging and distribution. The importance and benefits of banking clinical grade adult stem cells are also discussed.

  3. Environmentally induced transgenerational epigenetic reprogramming of primordial germ cells and the subsequent germ line.

    Directory of Open Access Journals (Sweden)

    Michael K Skinner

    Full Text Available A number of environmental factors (e.g. toxicants have been shown to promote the epigenetic transgenerational inheritance of disease and phenotypic variation. Transgenerational inheritance requires the germline transmission of altered epigenetic information between generations in the absence of direct environmental exposures. The primary periods for epigenetic programming of the germ line are those associated with primordial germ cell development and subsequent fetal germline development. The current study examined the actions of an agricultural fungicide vinclozolin on gestating female (F0 generation progeny in regards to the primordial germ cell (PGC epigenetic reprogramming of the F3 generation (i.e. great-grandchildren. The F3 generation germline transcriptome and epigenome (DNA methylation were altered transgenerationally. Interestingly, disruptions in DNA methylation patterns and altered transcriptomes were distinct between germ cells at the onset of gonadal sex determination at embryonic day 13 (E13 and after cord formation in the testis at embryonic day 16 (E16. A larger number of DNA methylation abnormalities (epimutations and transcriptional alterations were observed in the E13 germ cells than in the E16 germ cells. These observations indicate that altered transgenerational epigenetic reprogramming and function of the male germline is a component of vinclozolin induced epigenetic transgenerational inheritance of disease. Insights into the molecular control of germline transmitted epigenetic inheritance are provided.

  4. Concise Review: Quiescence in Adult Stem Cells

    DEFF Research Database (Denmark)

    Rumman, M; Dhawan, J; Kassem, Moustapha

    2015-01-01

    Adult stem cells (ASCs) are tissue resident stem cells responsible for tissue homeostasis and regeneration following injury. In uninjured tissues, ASCs exist in a nonproliferating, reversibly cell cycle-arrested state known as quiescence or G0. A key function of the quiescent state is to preserve...... stemness in ASCs by preventing precocious differentiation, and thus maintaining a pool of undifferentiated ASCs. Recent evidences suggest that quiescence is an actively maintained state and that excessive or defective quiescence may lead to compromised tissue regeneration or tumorigenesis. The aim...

  5. Germ-line CAG repeat instability causes extreme CAG repeat expansion with infantile-onset spinocerebellar ataxia type 2

    DEFF Research Database (Denmark)

    Vinther-Jensen, Tua; Ek, Jakob; Duno, Morten

    2013-01-01

    The spinocerebellar ataxias (SCA) are a genetically and clinically heterogeneous group of diseases, characterized by dominant inheritance, progressive cerebellar ataxia and diverse extracerebellar symptoms. A subgroup of the ataxias is caused by unstable CAG-repeat expansions in their respective ...... of paternal germ-line repeat sequence instability of the expanded SCA2 locus.European Journal of Human Genetics advance online publication, 10 October 2012; doi:10.1038/ejhg.2012.231....

  6. The DEAD-box protein MEL-46 is required in the germ line of the nematode Caenorhabditis elegans.

    Science.gov (United States)

    Minasaki, Ryuji; Puoti, Alessandro; Streit, Adrian

    2009-06-17

    In the hermaphrodite of the nematode Caenorhabditis elegans, the first germ cells differentiate as sperm. Later the germ line switches to the production of oocytes. This process requires the activity of a genetic regulatory network that includes among others the fem, fog and mog genes. The function of some of these genes is germline specific while others also act in somatic tissues. DEAD box proteins have been shown to be involved in the control of gene expression at different steps such as transcription and pre-mRNA processing. We show that the Caenorhabditis elegans gene mel-46 (maternal effect lethal) encodes a DEAD box protein that is related to the mammalian DDX20/Gemin3/DP103 genes. mel-46 is expressed throughout development and mutations in mel-46 display defects at multiple developmental stages. Here we focus on the role of mel-46 in the hermaphrodite germ line. mel-46(yt5) mutant hermaphrodites are partially penetrant sterile and fully penetrant maternal effect lethal. The germ line of mutants shows variable defects in oogenesis. Further, mel-46(yt5) suppresses the complete feminization caused by mutations in fog-2 and fem-3, two genes that are at the top and the center, respectively, of the genetic germline sex determining cascade, but not fog-1 that is at the bottom of this cascade. The C. elegans gene mel-46 encodes a DEAD box protein that is required maternally for early embryogenesis and zygotically for postembryonic development. In the germ line, it is required for proper oogenesis. Although it interacts genetically with genes of the germline sex determination machinery its primary function appears to be in oocyte differentiation rather than sex determination.

  7. The clinical phenotype of Lynch syndrome due to germ-line PMS2 mutations.

    Science.gov (United States)

    Senter, Leigha; Clendenning, Mark; Sotamaa, Kaisa; Hampel, Heather; Green, Jane; Potter, John D; Lindblom, Annika; Lagerstedt, Kristina; Thibodeau, Stephen N; Lindor, Noralane M; Young, Joanne; Winship, Ingrid; Dowty, James G; White, Darren M; Hopper, John L; Baglietto, Laura; Jenkins, Mark A; de la Chapelle, Albert

    2008-08-01

    Although the clinical phenotype of Lynch syndrome (also known as hereditary nonpolyposis colorectal cancer) has been well described, little is known about disease in PMS2 mutation carriers. Now that mutation detection methods can discern mutations in PMS2 from mutations in its pseudogenes, more mutation carriers have been identified. Information about the clinical significance of PMS2 mutations is crucial for appropriate counseling. Here, we report the clinical characteristics of a large series of PMS2 mutation carriers. We performed PMS2 mutation analysis using long-range polymerase chain reaction and multiplex ligation-dependent probe amplification for 99 probands diagnosed with Lynch syndrome-associated tumors showing isolated loss of PMS2 by immunohistochemistry. Penetrance was calculated using a modified segregation analysis adjusting for ascertainment. Germ-line PMS2 mutations were detected in 62% of probands (n = 55 monoallelic; 6 biallelic). Among families with monoallelic PMS2 mutations, 65.5% met revised Bethesda guidelines. Compared with the general population, in mutation carriers, the incidence of colorectal cancer was 5.2-fold higher, and the incidence of endometrial cancer was 7.5-fold higher. In North America, this translates to a cumulative cancer risk to age 70 years of 15%-20% for colorectal cancer, 15% for endometrial cancer, and 25%-32% for any Lynch syndrome-associated cancer. No elevated risk for non-Lynch syndrome-associated cancers was observed. PMS2 mutations contribute significantly to Lynch syndrome, but the penetrance for monoallelic mutation carriers appears to be lower than that for the other mismatch repair genes. Modified counseling and cancer surveillance guidelines for PMS2 mutation carriers are proposed.

  8. Germ-line mutations of the p53 tumor suppressor gene in patients with high risk for cancer inactivate the p53 protein.

    OpenAIRE

    Frebourg, T; Kassel, J; Lam, K T; Gryka, M A; Barbier, N; Andersen, T I; Børresen, A L; Friend, S H

    1992-01-01

    Germ-line mutations in the p53 tumor suppressor gene have been observed in patients with Li-Fraumeni syndrome, brain tumors, second malignancies, and breast cancers. It is unclear whether all of these mutations have inactivated p53 and thereby provide an increased risk for cancer. Therefore, it is necessary to establish the biological significance of these germ-line mutations by the functional and structural analysis of the resulting mutant p53 proteins. We analyzed the ability of seven germ-...

  9. Adult Stem Cell Therapy for Stroke: Challenges and Progress

    Science.gov (United States)

    Bang, Oh Young; Kim, Eun Hee; Cha, Jae Min; Moon, Gyeong Joon

    2016-01-01

    Stroke is one of the leading causes of death and physical disability among adults. It has been 15 years since clinical trials of stem cell therapy in patients with stroke have been conducted using adult stem cells like mesenchymal stem cells and bone marrow mononuclear cells. Results of randomized controlled trials showed that adult stem cell therapy was safe but its efficacy was modest, underscoring the need for new stem cell therapy strategies. The primary limitations of current stem cell therapies include (a) the limited source of engraftable stem cells, (b) the presence of optimal time window for stem cell therapies, (c) inherited limitation of stem cells in terms of growth, trophic support, and differentiation potential, and (d) possible transplanted cell-mediated adverse effects, such as tumor formation. Here, we discuss recent advances that overcome these hurdles in adult stem cell therapy for stroke. PMID:27733032

  10. Adult Mammalian Neural Stem Cells and Neurogenesis: Five Decades Later

    Science.gov (United States)

    Bond, Allison M.; Ming, Guo-li; Song, Hongjun

    2015-01-01

    Summary Adult somatic stem cells in various organs maintain homeostatic tissue regeneration and enhance plasticity. Since its initial discovery five decades ago, investigations of adult neurogenesis and neural stem cells have led to an established and expanding field that has significantly influenced many facets of neuroscience, developmental biology and regenerative medicine. Here we review recent progress and focus on questions related to adult mammalian neural stem cells that also apply to other somatic stem cells. We further discuss emerging topics that are guiding the field toward better understanding adult neural stem cells and ultimately applying these principles to improve human health. PMID:26431181

  11. Differential expression of conserved germ line markers and delayed segregation of male and female primordial germ cells in a hermaphrodite, the leech helobdella.

    Science.gov (United States)

    Cho, Sung-Jin; Vallès, Yvonne; Weisblat, David A

    2014-02-01

    In sexually reproducing animals, primordial germ cells (PGCs) are often set aside early in embryogenesis, a strategy that minimizes the risk of genomic damage associated with replication and mitosis during the cell cycle. Here, we have used germ line markers (piwi, vasa, and nanos) and microinjected cell lineage tracers to show that PGC specification in the leech genus Helobdella follows a different scenario: in this hermaphrodite, the male and female PGCs segregate from somatic lineages only after more than 20 rounds of zygotic mitosis; the male and female PGCs share the same (mesodermal) cell lineage for 19 rounds of zygotic mitosis. Moreover, while all three markers are expressed in both male and female reproductive tissues of the adult, they are expressed differentially between the male and female PGCs of the developing embryo: piwi and vasa are expressed preferentially in female PGCs at a time when nanos is expressed preferentially in male PGCs. A priori, the delayed segregation of male and female PGCs from somatic tissues and from one another increases the probability of mutations affecting both male and female PGCs of a given individual. We speculate that this suite of features, combined with a capacity for self-fertilization, may contribute to the dramatically rearranged genome of Helobdella robusta relative to other animals.

  12. Germ-line PHD1 and PHD2 mutations detected in patients with pheochromocytoma/paraganglioma-polycythemia.

    Science.gov (United States)

    Yang, Chunzhang; Zhuang, Zhengping; Fliedner, Stephanie M J; Shankavaram, Uma; Sun, Michael G; Bullova, Petra; Zhu, Roland; Elkahloun, Abdel G; Kourlas, Peter J; Merino, Maria; Kebebew, Electron; Pacak, Karel

    2015-01-01

    We have investigated genetic/pathogenetic factors associated with a new clinical entity in patients presenting with pheochromocytoma/paraganglioma (PHEO/PGL) and polycythemia. Two patients without hypoxia-inducible factor 2α (HIF2A) mutations, who presented with similar clinical manifestations, were analyzed for other gene mutations, including prolyl hydroxylase (PHD) mutations. We have found for the first time a germ-line mutation in PHD1 in one patient and a novel germ-line PHD2 mutation in a second patient. Both mutants exhibited reduced protein stability with substantial quantitative protein loss and thus compromised catalytic activities. Due to the unique association of patients' polycythemia with borderline or mildly elevated erythropoietin (EPO) levels, we also performed an in vitro sensitivity assay of erythroid progenitors to EPO and for EPO receptor (EPOR) expression. The results show inappropriate hypersensitivity of erythroid progenitors to EPO in these patients, indicating increased EPOR expression/activity. In addition, the present study indicates that HIF dysregulation due to PHD mutations plays an important role in the pathogenesis of these tumors and associated polycythemia. The PHD1 mutation appears to be a new member contributing to the genetic landscape of this novel clinical entity. Our results support the existence of a specific PHD1- and PHD2-associated PHEO/PGL-polycythemia disorder. • A novel germ-l i n e PHD1 mutation causing heochromocytoma/paraganglioma and polycythemia. • Increased EPOR activity and inappropriate hypersensitivity of erythroid progenitors to EPO.

  13. Purification of Oogonial Stem Cells From Adult Mouse and Human Ovaries: An Assessment of the Literature and a View Toward the Future

    OpenAIRE

    Woods, Dori C.; White, Yvonne A. R.; Tilly, Jonathan L.

    2013-01-01

    Contemporary claims that mitotically active female germ line or oogonial stem cells (OSCs) exist and support oogenesis during postnatal life in mammals have been debated in the field of reproductive biology since March 2004, when a mouse study posed the first serious challenge to the dogma of a fixed pool of oocytes being endowed at birth in more than 50 years. Other studies have since been put forth that further question the validity of this dogma, including the isolation of OSCs from neonat...

  14. Purification of oogonial stem cells from adult mouse and human ovaries: an assessment of the literature and a view toward the future.

    Science.gov (United States)

    Woods, Dori C; White, Yvonne A R; Tilly, Jonathan L

    2013-01-01

    Contemporary claims that mitotically active female germ line or oogonial stem cells (OSCs) exist and support oogenesis during postnatal life in mammals have been debated in the field of reproductive biology since March 2004, when a mouse study posed the first serious challenge to the dogma of a fixed pool of oocytes being endowed at birth in more than 50 years. Other studies have since been put forth that further question the validity of this dogma, including the isolation of OSCs from neonatal and adult mouse ovaries by 4 independent groups using multiple strategies. Two of these groups also reported that isolated mouse OSCs, once transplanted back into ovaries of adult female mice, differentiate into fully functional eggs that ovulate, fertilize, and produce healthy embryos and offspring. Arguably, one of the most significant advances in this emerging field was provided by a new research study published this year, which reported the successful isolation and functional characterization of OSCs from ovaries of reproductive age women. Two commentaries on this latest work, one cautiously supportive and one highly skeptical, were published soon afterward. This article evaluates the current literature regarding postnatal oogenesis in mammals and discusses important next steps for future work on OSC biology and function.

  15. Dental Stem Cell in Tooth Development and Advances of Adult Dental Stem Cell in Regenerative Therapies.

    Science.gov (United States)

    Tan, Jiali; Xu, Xin; Lin, Jiong; Fan, Li; Zheng, Yuting; Kuang, Wei

    2015-01-01

    Stem cell-based therapies are considered as a promising treatment for many clinical usage such as tooth regeneration, bone repairation, spinal cord injury, and so on. However, the ideal stem cell for stem cell-based therapy still remains to be elucidated. In the past decades, several types of stem cells have been isolated from teeth, including dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), dental follicle progenitor stem cells (DFPCs) and stem cells from apical papilla (SCAP), which may be a good source for stem cell-based therapy in certain disease, especially when they origin from neural crest is considered. In this review, the specific characteristics and advantages of the adult dental stem cell population will be summarized and the molecular mechanisms of the differentiation of dental stem cell during tooth development will be also discussed.

  16. Radiation-induced germ-line mutations detected by a direct comparison of parents and children DNA sequences containing SNPs

    International Nuclear Information System (INIS)

    Morimyo, M.; Hongo, E.; Higashi, T.; Wu, J.; Matsumoto, I.; Okamoto, M.; Kawano, A.; Tsuji, S.

    2003-01-01

    Full text: Germ-line mutation is detected in mice but not in humans. To estimate genetic risk of humans, a new approach to extrapolate from animal data to humans or to directly detect radiation-induced mutations in man is expected. We have developed a new method to detect germ-line mutations by directly comparing DNA sequences of parents and children. The nucleotide sequences among mouse strains are almost identical except SNP markers that are detected at 1/1000 frequency. When gamma-irradiated male mice are mated with female mice, heterogeneous nucleotide sequences induced in children DNA are a candidate of mutation, whose assignment can be done by SNP analysis. This system can easily detect all types of mutations such as transition, transversion, frameshift and deletion induced by radiation and can be applied to humans having genetically heterogeneous nucleotide sequences and many SNP markers. C3H male mice of 8 weeks of gestation were irradiated with gamma rays of 3 and 1 Gy and after 3 weeks, they were mated with the same aged C57BL female mice. After 3 weeks breeding, DNA was extracted from parents and children mice. The nucleotide sequences of 150 STS markers containing 300-900 bp and SNPs of parents and children DNA were determined by a direct sequencing; amplification of STS markers by Taq DNA polymerase, purification of PCR products, and DNA sequencing with a dye-terminator method. At each radiation dose, a total amount of 5 Mb DNA sequences were examined to detect radiation-induced mutations. We could find 6 deletions in 3 Gy irradiated mice but not in 1 Gy and control mice. The mutation frequency was about 4.0 x 10 -7 /bp/ Gy or 1.6 x 10 -4 /locus/Gy, and suggested the non-linear increase of mutation rate with dose

  17. Analysis of the cytoskeleton organization and its possible functions in male earthworm germ-line cysts equipped with a cytophore.

    Science.gov (United States)

    Małota, Karol; Świątek, Piotr

    2016-10-01

    We studied the organization of F-actin and the microtubular cytoskeleton in male germ-line cysts in the seminal vesicles of the earthworm Dendrobaena veneta using light, fluorescent and electron microscopy along with both chemically fixed tissue and life cell imaging. Additionally, in order to follow the functioning of the cytoskeleton, we incubated the cysts in colchicine, nocodazole, cytochalasin D and latrunculin A. The male germ-line cells of D. veneta are interconnected via stable intercellular bridges (IB), and form syncytial cysts. Each germ cell has only one IB that connects it to the anuclear central cytoplasmic mass, the cytophore. During the studies, we analyzed the cytoskeleton in spermatogonial, spermatocytic and spermatid cysts. F-actin was detected in the cortical cytoplasm and forms distinct rings in the IBs. The arrangement of the microtubules changed dynamically during spermatogenesis. The microtubules are distributed evenly in whole spermatogonial and spermatocytic cysts; however, they primarily accumulate within the IBs in spermatogonia. In early spermatids, microtubules pass through the IBs and are present in whole cysts. During spermatid elongation, the microtubules form a manchette while they are absent in the cytophore and in the IBs. Use of cytoskeletal drugs did not alter the general morphology of the cysts. Detectable effects-the occurrence of nuclei in the late spermatids and manchette fragments in the cytophore-were observed only after incubation in nocodazole. Our results suggest that the microtubules are responsible for cytoplasmic/organelle transfer between the germ cells and the cytophore during spermatogenesis and for the positioning of the spermatid nuclei.

  18. Intestinal stem cells in the adult Drosophila midgut

    International Nuclear Information System (INIS)

    Jiang, Huaqi; Edgar, Bruce A.

    2011-01-01

    Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: ► The homeostasis and regeneration of adult fly midguts are mediated by ISCs. ► Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). ► EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. ► Notch signaling regulates ISC self-renewal and differentiation.

  19. Translational applications of adult stem cell-derived organoids

    NARCIS (Netherlands)

    Drost, Jarno; Clevers, Hans

    2017-01-01

    Adult stem cells from a variety of organs can be expanded long-term in vitro as three-dimensional organotypic structures termed organoids. These adult stem cell-derived organoids retain their organ identity and remain genetically stable over long periods of time. The ability to grow organoids from

  20. Recruitment of Mediator Complex by Cell Type and Stage-Specific Factors Required for Tissue-Specific TAF Dependent Gene Activation in an Adult Stem Cell Lineage.

    Science.gov (United States)

    Lu, Chenggang; Fuller, Margaret T

    2015-12-01

    Onset of terminal differentiation in adult stem cell lineages is commonly marked by robust activation of new transcriptional programs required to make the appropriate differentiated cell type(s). In the Drosophila male germ line stem cell lineage, the switch from proliferating spermatogonia to spermatocyte is accompanied by one of the most dramatic transcriptional changes in the fly, as over 1000 new transcripts turn on in preparation for meiosis and spermatid differentiation. Here we show that function of the coactivator complex Mediator is required for activation of hundreds of new transcripts in the spermatocyte program. Mediator appears to act in a sequential hierarchy, with the testis activating Complex (tMAC), a cell type specific form of the Mip/dREAM general repressor, required to recruit Mediator subunits to the chromatin, and Mediator function required to recruit the testis TAFs (tTAFs), spermatocyte specific homologs of subunits of TFIID. Mediator, tMAC and the tTAFs co-regulate expression of a major set of spermatid differentiation genes. The Mediator subunit Med22 binds the tMAC component Topi when the two are coexpressed in S2 cells, suggesting direct recruitment. Loss of Med22 function in spermatocytes causes meiosis I maturation arrest male infertility, similar to loss of function of the tMAC subunits or the tTAFs. Our results illuminate how cell type specific versions of the Mip/dREAM complex and the general transcription machinery cooperate to drive selective gene activation during differentiation in stem cell lineages.

  1. Recruitment of Mediator Complex by Cell Type and Stage-Specific Factors Required for Tissue-Specific TAF Dependent Gene Activation in an Adult Stem Cell Lineage.

    Directory of Open Access Journals (Sweden)

    Chenggang Lu

    2015-12-01

    Full Text Available Onset of terminal differentiation in adult stem cell lineages is commonly marked by robust activation of new transcriptional programs required to make the appropriate differentiated cell type(s. In the Drosophila male germ line stem cell lineage, the switch from proliferating spermatogonia to spermatocyte is accompanied by one of the most dramatic transcriptional changes in the fly, as over 1000 new transcripts turn on in preparation for meiosis and spermatid differentiation. Here we show that function of the coactivator complex Mediator is required for activation of hundreds of new transcripts in the spermatocyte program. Mediator appears to act in a sequential hierarchy, with the testis activating Complex (tMAC, a cell type specific form of the Mip/dREAM general repressor, required to recruit Mediator subunits to the chromatin, and Mediator function required to recruit the testis TAFs (tTAFs, spermatocyte specific homologs of subunits of TFIID. Mediator, tMAC and the tTAFs co-regulate expression of a major set of spermatid differentiation genes. The Mediator subunit Med22 binds the tMAC component Topi when the two are coexpressed in S2 cells, suggesting direct recruitment. Loss of Med22 function in spermatocytes causes meiosis I maturation arrest male infertility, similar to loss of function of the tMAC subunits or the tTAFs. Our results illuminate how cell type specific versions of the Mip/dREAM complex and the general transcription machinery cooperate to drive selective gene activation during differentiation in stem cell lineages.

  2. Strategies to Optimize Adult Stem Cell Therapy for Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Shan Liu

    2016-06-01

    Full Text Available Stem cell therapy aims to replace damaged or aged cells with healthy functioning cells in congenital defects, tissue injuries, autoimmune disorders, and neurogenic degenerative diseases. Among various types of stem cells, adult stem cells (i.e., tissue-specific stem cells commit to becoming the functional cells from their tissue of origin. These cells are the most commonly used in cell-based therapy since they do not confer risk of teratomas, do not require fetal stem cell maneuvers and thus are free of ethical concerns, and they confer low immunogenicity (even if allogenous. The goal of this review is to summarize the current state of the art and advances in using stem cell therapy for tissue repair in solid organs. Here we address key factors in cell preparation, such as the source of adult stem cells, optimal cell types for implantation (universal mesenchymal stem cells vs. tissue-specific stem cells, or induced vs. non-induced stem cells, early or late passages of stem cells, stem cells with endogenous or exogenous growth factors, preconditioning of stem cells (hypoxia, growth factors, or conditioned medium, using various controlled release systems to deliver growth factors with hydrogels or microspheres to provide apposite interactions of stem cells and their niche. We also review several approaches of cell delivery that affect the outcomes of cell therapy, including the appropriate routes of cell administration (systemic, intravenous, or intraperitoneal vs. local administration, timing for cell therapy (immediate vs. a few days after injury, single injection of a large number of cells vs. multiple smaller injections, a single site for injection vs. multiple sites and use of rodents vs. larger animal models. Future directions of stem cell-based therapies are also discussed to guide potential clinical applications.

  3. Germ line transformation of the yellow fever mosquito, Aedes aegypti, mediated by transpositional insertion of a piggyBac vector.

    Science.gov (United States)

    Lobo, N F; Hua-Van, A; Li, X; Nolen, B M; Fraser, M J

    2002-04-01

    Mosquito-vectored diseases such as yellow fever and dengue fever continue to have a substantial impact on human populations world-wide. Novel strategies for control of these mosquito vectored diseases can arise through the development of reliable systems for genetic manipulation of the insect vector. A piggyBac vector marked with the Drosophila melanogaster cinnabar (cn) gene was used to transform the white-eyed khw strain of Aedes aegypti. Microinjection of preblastoderm embryos resulted in four families of cinnabar transformed insects. An overall transformation frequency of 4%, with a range of 0% to as high as 13% for individual experiments, was achieved when using a heat-shock induced transposase providing helper plasmid. Southern hybridizations indicated multiple insertion events in three of four transgenic lines, while the presence of duplicated target TTAA sites at either ends of individual insertions confirmed characteristic piggyBac transposition events in these three transgenic lines. The transgenic phenotype has remained stable for more than twenty generations. The transformations effected using the piggyBac element establish the potential of this element as a germ-line transformation vector for Aedine mosquitoes.

  4. Isolation of oogenesis-specific genes transcribed in the germ-line of Calliphora erythrocephala and Drosophila melanogaster

    International Nuclear Information System (INIS)

    Tucker, M.A.

    1988-01-01

    Poly(A) + RNA from early or mid-stage ovarian follicles of C. erythrocephala was used to generate radiolabelled oogenesis-specific cDNA probes for screening the phage libraries. A cDNA probe made from mid-stage embryo poly(A) + RNA was used as the differential screening probe. Thus plaques hybridizing to the two oogenesis-specific probes but not the mid-stage embryo probe were selected as potentially containing oogenesis-specific genes. Two further rounds of screening were used to eliminate false positives and, after plaque purification, restriction digests of the remaining clones were screened by Southern blot hybridization to identify DNA fragments transcribed in an oogenesis-specific manner. In situ hybridization to sections of ovarian follicles has been used to determine the cell types within the follicles in which the various genes are expressed. Radiolabelled RNA probes for four of the C. erythrocephala oogenesis-specific clones and the two D. melanogaster clones have been hybridized to ovarian follicles. Further studies have been concentrated on the two germ-line transcribed, oogenesis-specific clones isolated from the D. melanogaster clone library. Detailed genetic mapping of the DA clone and of these mutations was performed to determine which mutations might represent the DA gene. cDNA clones have been isolated for the transcribed region of clone DA and have been used to further define the transcription unit from this region of the D. melanogaster genome

  5. Coexistence of Quiescent and Active Adult Stem Cells in Mammals

    NARCIS (Netherlands)

    Li, Linheng; Clevers, Hans

    2010-01-01

    Adult stem cells are crucial for physiological tissue renewal and regeneration after injury. Prevailing models assume the existence of a single quiescent population of stem cells residing in a specialized niche of a given tissue. Emerging evidence indicates that both quiescent (out of cell cycle and

  6. Evolutionary insights into postembryonic development of adult intestinal stem cells

    Directory of Open Access Journals (Sweden)

    Ishizuya-Oka Atsuko

    2011-11-01

    Full Text Available Abstract In the adult vertebrate intestine, multi-potent stem cells continuously generate all of the epithelial cells throughout the adulthood. While it has long been known that the frog intestine is formed via the development of adult intestinal stem cells during thyroid hormone (TH-dependent metamorphosis, the basic structure of the adult intestine is formed by birth in mammals and it is unclear if the subsequent maturation of the intestine involves any changes in the intestinal stem cells. Two recent papers showing that B lymphocyte-induced maturation protein 1 (Blimp1 regulates postnatal epithelial stem cell reprogramming during mouse intestinal maturation support the model that adult intestinal stem cells are developed during postembryonic development in mammals, in a TH-dependent process similar to intestinal remodeling during amphibian metamorphosis. Since the formation of the adult intestine in both mammals and amphibians is closely associated with the adaptation from aquatic to terrestrial life during the peak of endogenous TH levels, the molecular mechanisms by which the adult stem cells are developed are likely evolutionally conserved.

  7. Ovarian Stem Cells–-the Pros and Cons

    Directory of Open Access Journals (Sweden)

    Ayelet Evron

    2013-01-01

    Full Text Available The potential for postnatal de novo oogenesis in mammals and in humans has become very controversial in the fields of reproductive science and biology. Historically, it has been thought that females of most mammalian species lose the ability to produce oocytes at birth. A contemporary understanding of stem cell biology together with novel experimental methods has challenged the model of a prenatal fixed ovarian primordial follicle pool that declines with age. Researchers have suggested replenishment of post-natal oocytes by germ-line stem cells (GSCs. According to this theory, GSCs produce oocytes and primordial follicles throughout the lifetime of the adult female. This review describes recent approaches supporting the revolutionary idea of de novo oogenesis in mammals and humans of reproductive-age and provides counter arguments from opponents of this novel and innovative concept.

  8. MSH6 and PMS2 germ-line pathogenic variants implicated in Lynch syndrome are associated with breast cancer.

    Science.gov (United States)

    Roberts, Maegan E; Jackson, Sarah A; Susswein, Lisa R; Zeinomar, Nur; Ma, Xinran; Marshall, Megan L; Stettner, Amy R; Milewski, Becky; Xu, Zhixiong; Solomon, Benjamin D; Terry, Mary Beth; Hruska, Kathleen S; Klein, Rachel T; Chung, Wendy K

    2018-01-18

    PurposeAn association of Lynch syndrome (LS) with breast cancer has been long suspected; however, there have been insufficient data to address this question for each of the LS genes individually.MethodsWe conducted a retrospective review of personal and family history in 423 women with pathogenic or likely pathogenic germ-line variants in MLH1 (N = 65), MSH2 (N = 94), MSH6 (N = 140), or PMS2 (N = 124) identified via clinical multigene hereditary cancer testing. Standard incidence ratios (SIRs) of breast cancer were calculated by comparing breast cancer frequencies in our study population with those in the general population (Surveillance, Epidemiology, and End Results 18 data).ResultsWhen evaluating by gene, the age-standardized breast cancer risks for MSH6 (SIR = 2.11; 95% confidence interval (CI), 1.56-2.86) and PMS2 (SIR = 2.92; 95% CI, 2.17-3.92) were associated with a statistically significant risk for breast cancer whereas no association was observed for MLH1 (SIR = 0.87; 95% CI, 0.42-1.83) or MSH2 (SIR = 1.22; 95% CI, 0.72-2.06).ConclusionOur data demonstrate that two LS genes, MSH6 and PMS2, are associated with an increased risk for breast cancer and should be considered when ordering genetic testing for individuals who have a personal and/or family history of breast cancer.GENETICS in MEDICINE advance online publication, 18 January 2018; doi:10.1038/gim.2017.254.

  9. Intestinal stem cells in the adult Drosophila midgut

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Huaqi, E-mail: Huaqi.Jiang@UTSouthwestern.edu [Department of Developmental Biology, UT Southwestern Medical Center, 6000 Harry Hines Blvd., Dallas, TX, 75235 (United States); Edgar, Bruce A., E-mail: b.edgar@dkfz.de [ZMBH-DKFZ Alliance, Im Neuenheimer Feld 282, D-69120 Heidelberg (Germany); Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Seattle, WA 98109 (United States)

    2011-11-15

    Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: Black-Right-Pointing-Pointer The homeostasis and regeneration of adult fly midguts are mediated by ISCs. Black-Right-Pointing-Pointer Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). Black-Right-Pointing-Pointer EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. Black-Right-Pointing-Pointer Notch signaling regulates ISC self-renewal and differentiation.

  10. Muscle Stem Cells: A Model System for Adult Stem Cell Biology.

    Science.gov (United States)

    Cornelison, Ddw; Perdiguero, Eusebio

    2017-01-01

    Skeletal muscle stem cells, originally termed satellite cells for their position adjacent to differentiated muscle fibers, are absolutely required for the process of skeletal muscle repair and regeneration. In the last decade, satellite cells have become one of the most studied adult stem cell systems and have emerged as a standard model not only in the field of stem cell-driven tissue regeneration but also in stem cell dysfunction and aging. Here, we provide background in the field and discuss recent advances in our understanding of muscle stem cell function and dysfunction, particularly in the case of aging, and the potential involvement of muscle stem cells in genetic diseases such as the muscular dystrophies.

  11. Adult neural stem cells: The promise of the future

    Directory of Open Access Journals (Sweden)

    Philippe Taupin

    2007-01-01

    Full Text Available Philippe TaupinNational Neuroscience Institute, National University of SingaporeAbstract: Stem cells are self-renewing undifferentiated cells that give rise to multiple types of specialized cells of the body. In the adult, stem cells are multipotents and contribute to homeostasis of the tissues and regeneration after injury. Until recently, it was believed that the adult brain was devoid of stem cells, hence unable to make new neurons and regenerate. With the recent evidences that neurogenesis occurs in the adult brain and neural stem cells (NSCs reside in the adult central nervous system (CNS, the adult brain has the potential to regenerate and may be amenable to repair. The function(s of NSCs in the adult CNS remains the source of intense research and debates. The promise of the future of adult NSCs is to redefine the functioning and physiopathology of the CNS, as well as to treat a broad range of CNS diseases and injuries.Keywords: neurogenesis, transdifferentiation, plasticity, cellular therapy

  12. Dll1 maintains quiescence of adult neural stem cells and segregates asymmetrically during mitosis

    OpenAIRE

    Kawaguchi, Daichi; Furutachi, Shohei; Kawai, Hiroki; Hozumi, Katsuto; Gotoh, Yukiko

    2013-01-01

    Stem cells often divide asymmetrically to produce one stem cell and one differentiating cell, thus maintaining the stem cell pool. Although neural stem cells (NSCs) in the adult mouse subventricular zone have been suggested to divide asymmetrically, intrinsic cell fate determinants for asymmetric NSC division are largely unknown. Stem cell niches are important for stem cell maintenance, but the niche for the maintenance of adult quiescent NSCs has remained obscure. Here we show that the Notch...

  13. Towards gene banking amphibian maternal germ lines: short-term incubation, cryoprotectant tolerance and cryopreservation of embryonic cells of the frog, Limnodynastes peronii.

    Science.gov (United States)

    Lawson, Bianca; Clulow, Simon; Mahony, Michael J; Clulow, John

    2013-01-01

    Gene banking is arguably the best method available to prevent the loss of genetic diversity caused by declines in wild populations, when the causes of decline cannot be halted or reversed. For one of the most impacted vertebrate groups, the amphibians, gene banking technologies have advanced considerably, and gametes from the male line can be banked successfully for many species. However, cryopreserving the female germ line remains challenging, with attempts at cryopreserving oocytes unsuccessful due to their large size and yolk content. One possible solution is to target cryopreservation of early embryos that contain the maternal germ line, but consist of smaller cells. Here, we investigate the short term incubation, cryoprotectant tolerance, and cryopreservation of dissociated early embryonic cells from gastrulae and neurulae of the Striped Marsh Frog, Limnodynastes peronii. Embryos were dissociated and cells were incubated for up to 24 hours in various media. Viability of both gastrula and neurula cells remained high (means up to 40-60%) over 24 hours of incubation in all media, although viability was maintained at a higher level in Ca(2+)-free Simplified Amphibian Ringer; low speed centrifugation did not reduce cell viability. Tolerance of dissociated embryonic cells was tested for two cryoprotectants, glycerol and dimethyl sulphoxide; dissociated cells of both gastrulae and neurulae were highly tolerant to both-indeed, cell viability over 24 hours was higher in media containing low-to-medium concentrations than in equivalent cryoprotectant-free media. Viability over 24 hours was lower in concentrations of cryoprotectant higher than 10%. Live cells were recovered following cryopreservation of both gastrula and neurula cells, but only at low rates. Optimal cryodiluents were identified for gastrula and neurula cells. This is the first report of a slow cooling protocol for cryopreservation of amphibian embryonic cells, and sets future research directions for

  14. Towards gene banking amphibian maternal germ lines: short-term incubation, cryoprotectant tolerance and cryopreservation of embryonic cells of the frog, Limnodynastes peronii.

    Directory of Open Access Journals (Sweden)

    Bianca Lawson

    Full Text Available Gene banking is arguably the best method available to prevent the loss of genetic diversity caused by declines in wild populations, when the causes of decline cannot be halted or reversed. For one of the most impacted vertebrate groups, the amphibians, gene banking technologies have advanced considerably, and gametes from the male line can be banked successfully for many species. However, cryopreserving the female germ line remains challenging, with attempts at cryopreserving oocytes unsuccessful due to their large size and yolk content. One possible solution is to target cryopreservation of early embryos that contain the maternal germ line, but consist of smaller cells. Here, we investigate the short term incubation, cryoprotectant tolerance, and cryopreservation of dissociated early embryonic cells from gastrulae and neurulae of the Striped Marsh Frog, Limnodynastes peronii. Embryos were dissociated and cells were incubated for up to 24 hours in various media. Viability of both gastrula and neurula cells remained high (means up to 40-60% over 24 hours of incubation in all media, although viability was maintained at a higher level in Ca(2+-free Simplified Amphibian Ringer; low speed centrifugation did not reduce cell viability. Tolerance of dissociated embryonic cells was tested for two cryoprotectants, glycerol and dimethyl sulphoxide; dissociated cells of both gastrulae and neurulae were highly tolerant to both-indeed, cell viability over 24 hours was higher in media containing low-to-medium concentrations than in equivalent cryoprotectant-free media. Viability over 24 hours was lower in concentrations of cryoprotectant higher than 10%. Live cells were recovered following cryopreservation of both gastrula and neurula cells, but only at low rates. Optimal cryodiluents were identified for gastrula and neurula cells. This is the first report of a slow cooling protocol for cryopreservation of amphibian embryonic cells, and sets future research

  15. Comparative aspects of adult neural stem cell activity in vertebrates.

    Science.gov (United States)

    Grandel, Heiner; Brand, Michael

    2013-03-01

    At birth or after hatching from the egg, vertebrate brains still contain neural stem cells which reside in specialized niches. In some cases, these stem cells are deployed for further postnatal development of parts of the brain until the final structure is reached. In other cases, postnatal neurogenesis continues as constitutive neurogenesis into adulthood leading to a net increase of the number of neurons with age. Yet, in other cases, stem cells fuel neuronal turnover. An example is protracted development of the cerebellar granular layer in mammals and birds, where neurogenesis continues for a few weeks postnatally until the granular layer has reached its definitive size and stem cells are used up. Cerebellar growth also provides an example of continued neurogenesis during adulthood in teleosts. Again, it is the granular layer that grows as neurogenesis continues and no definite adult cerebellar size is reached. Neuronal turnover is most clearly seen in the telencephalon of male canaries, where projection neurons are replaced in nucleus high vocal centre each year before the start of a new mating season--circuitry reconstruction to achieve changes of the song repertoire in these birds? In this review, we describe these and other examples of adult neurogenesis in different vertebrate taxa. We also compare the structure of the stem cell niches to find common themes in their organization despite different functions adult neurogenesis serves in different species. Finally, we report on regeneration of the zebrafish telencephalon after injury to highlight similarities and differences of constitutive neurogenesis and neuronal regeneration.

  16. The Ovary of Tubifex tubifex (Clitellata, Naididae, Tubificinae Is Composed of One, Huge Germ-Line Cyst that Is Enriched with Cytoskeletal Components.

    Directory of Open Access Journals (Sweden)

    Anna Z Urbisz

    Full Text Available Recent studies on the ovary organization and oogenesis in Tubificinae have revealed that their ovaries are small polarized structures that are composed of germ cells in subsequent stages of oogenesis that are associated with somatic cells. In syncytial cysts, as a rule, each germ cell is connected to the central cytoplasmic mass, the cytophore, via only one stable intercellular bridge (ring canal. In this paper we present detailed data about the composition of germ-line cysts in Tubifex tubifex with special emphasis on the occurrence and distribution of the cytoskeletal elements. Using fixed material and live cell imaging techniques, we found that the entire ovary of T. tubifex is composed of only one, huge multicellular germ-line cyst, which may contain up to 2,600 cells. Its architecture is broadly similar to the cysts that are found in other clitellate annelids, i.e. a common, anuclear cytoplasmic mass in the center of the cyst and germ cells that are connected to it via intercellular bridges. The cytophore in the T. tubifex cyst extends along the long axis of the ovary in the form of elongated and branched cytoplasmic strands. Rhodamine-coupled phalloidin staining revealed that the prominent strands of actin filaments occur inside the cytophore. Similar to the cytophore, F-actin strands are branched and they are especially well developed in the middle and outermost parts of the ovary. Microfilaments are also present in the ring canals that connect the germ cells with the cytophore in the narrow end of the ovary. Using TubulinTracker, we found that the microtubules form a prominent network of loosely and evenly distributed tubules inside the cytophore as well as in every germ cell. The well-developed cytoskeletal elements in T. tubifex ovary seem to ensure the integrity of such a huge germ-line cyst of complex (germ cells-ring canals-cytophore organization. A comparison between the cysts that are described here and other well-known female

  17. A novel germ-line point mutation in RET exon 8 (Gly(533)Cys) in a large kindred with familial medullary thyroid carcinoma

    OpenAIRE

    Silva, Adriana Madeira Alvares da [UNIFESP; Maciel, Rui Monteiro de Barros [UNIFESP; Dias-da-Silva, Magnus Régios [UNIFESP; Toledo, Silvia Regina Caminada de [UNIFESP; De Carvalho, Marcos B.; Cerutti, Janete Maria [UNIFESP

    2003-01-01

    Familial medullary thyroid carcinoma is related to germ-line mutations in the RET oncogene, mainly in cysteine codon 10 or 11, whereas noncysteine mutations in codons 13 - 15 are rare. We now report a new missense point mutation in exon 8 of the RET gene (1597G-->T) corresponding to a Gly(533)Cys substitution in the cystein-rich domain of RET protein in 76 patients from a 6-generation Brazilian family with 229 subjects, with ascendants from Spain. It is likely that the mutation causes familia...

  18. Further proof of the plasticity of adult stem cells and their role in tissue repair

    OpenAIRE

    Prockop, Darwin J.

    2003-01-01

    In this issue, De Bari et al. (2003) present elegant data to counter the recent claims that adult stem cells have a limited plasticity. Further, they provide evidence that adult stem cells can seek out damaged tissues and repair them.

  19. Adult Stromal (Skeletal, Mesenchymal) Stem Cells: Advances Towards Clinical Applications

    DEFF Research Database (Denmark)

    Kermani, Abbas Jafari; Harkness, Linda; Zaher, Walid

    2014-01-01

    Mesenchymal Stem Cells (MSC) are non-hematopoietic adult stromal cells that reside in a perivascular niche in close association with pericytes and endothelial cells and possess self-renewal and multi-lineage differentiation capacity. The origin, unique properties, and therapeutic benefits of MSC ...... the translation of MSC into clinic: Generation of MSC-like cells from human pluripotent stem cells, strategies to enhance homing of MSC to injured tissues, and targeting of MSC in vivo.......Mesenchymal Stem Cells (MSC) are non-hematopoietic adult stromal cells that reside in a perivascular niche in close association with pericytes and endothelial cells and possess self-renewal and multi-lineage differentiation capacity. The origin, unique properties, and therapeutic benefits of MSC...

  20. HPV-Induced Field Cancerisation: Transformation of Adult Tissue Stem Cell Into Cancer Stem Cell.

    Science.gov (United States)

    Olivero, Carlotta; Lanfredini, Simone; Borgogna, Cinzia; Gariglio, Marisa; Patel, Girish K

    2018-01-01

    Field cancerisation was originally described as a basis for multiple head and neck squamous cell carcinoma (HNSCC) and is a pre-malignant phenomenon that is frequently attributable to oncogenic human papillomavirus (HPV) infection. Our work on β-HPV-induced cutaneous squamous cell carcinomas identified a novel Lrig1+ hair follicle junctional zone keratinocyte stem cell population as the basis for field cancerisation. Herein, we describe the ability for HPV to infect adult tissue stem cells in order to establish persistent infection and induce their proliferation and displacement resulting in field cancerisation. By review of the HPV literature, we reveal how this mechanism is conserved as the basis of field cancerisation across many tissues. New insights have identified the capacity for HPV early region genes to dysregulate adult tissue stem cell self-renewal pathways ensuring that the expanded population preserve its stem cell characteristics beyond the stem cell niche. HPV-infected cells acquire additional transforming mutations that can give rise to intraepithelial neoplasia (IEN), from environmental factors such as sunlight or tobacco induced mutations in skin and oral cavity, respectively. With establishment of IEN, HPV viral replication is sacrificed with loss of the episome, and the tissue is predisposed to multiple cancer stem cell-driven carcinomas.

  1. Germ line mutations of mismatch repair genes in hereditary nonpolyposis colorectal cancer patients with small bowel cancer: International Society for Gastrointestinal Hereditary Tumours Collaborative Study

    DEFF Research Database (Denmark)

    Park, Jae-Gahb; Kim, Duck-Woo; Hong, Chang Won

    2006-01-01

    PURPOSE: The aim of study was to determine the clinical characteristics and mutational profiles of the mismatch repair genes in hereditary nonpolyposis colorectal cancer (HNPCC) patients with small bowel cancer (SBC). EXPERIMENTAL DESIGN: A questionnaire was mailed to 55 members of the Internatio......PURPOSE: The aim of study was to determine the clinical characteristics and mutational profiles of the mismatch repair genes in hereditary nonpolyposis colorectal cancer (HNPCC) patients with small bowel cancer (SBC). EXPERIMENTAL DESIGN: A questionnaire was mailed to 55 members...... of the International Society for Gastrointestinal Hereditary Tumours, requesting information regarding patients with HNPCC-associated SBC and germ line mismatch repair gene mutations. RESULTS: The study population consisted of 85 HNPCC patients with identified mismatch repair gene mutations and SBCs. SBC was the first...... HNPCC-associated malignancy in 14 of 41 (34.1%) patients for whom a personal history of HNPCC-associated cancers was available. The study population harbored 69 different germ line mismatch repair gene mutations, including 31 mutations in MLH1, 34 in MSH2, 3 in MSH6, and 1 in PMS2. We compared...

  2. Cuban experience with the therapeutic use of adult stem cells

    International Nuclear Information System (INIS)

    Hernandez Ramirez, Porfirio; Alfonso Simon, Amel; Aparicio Suarez, Jose L

    2011-01-01

    The basic and clinical researches carried out during past years on the stem cells and its therapeutic possibilities are at present times, one of the most interesting subjects of the contemporaneous medicine. There are advances in the study and application of adult stem cells showing remarkable advantages on the embryonic ones, since its handling is more simple, economic and they are obtained from the own subject to be treated. For the introduction in Cuba of the regenerative cellular therapy in the Institute of Hematology and Immunology the cellular sources selected were the adult stem cells derived from bone marrow and the mobilized ones to the peripheral blood. To make easy the expansion of treatment to other hospital centers, authors standardized a technique for the mobilization of the hematopoietic stem cells to peripheral blood using a granulocyte colony-stimulating factor (Filgrastim, of national production) developing a simple, economic and more tolerable method for patients. In this way, the cellular therapy has been expanded to 6 Cuban provinces and until April, 2009 562 cases with autologous adult stem cells transplant have been treated, from which the 81.7% to correspond to patients presenting with Angiology diseases with a significant reduction of major amputations. Also, the results have been very promising in the bone lesions and periodontal processes among other diseases treated. The results obtained until now may be considered as a new achievement of revolutionary science and of our national health systems and of science and technique. The method used is an economic and feasible procedure for the institutions with scarce resources

  3. Conversion of adult endothelium to immunocompetent haematopoietic stem cells.

    Science.gov (United States)

    Lis, Raphael; Karrasch, Charles C; Poulos, Michael G; Kunar, Balvir; Redmond, David; Duran, Jose G Barcia; Badwe, Chaitanya R; Schachterle, William; Ginsberg, Michael; Xiang, Jenny; Tabrizi, Arash Rafii; Shido, Koji; Rosenwaks, Zev; Elemento, Olivier; Speck, Nancy A; Butler, Jason M; Scandura, Joseph M; Rafii, Shahin

    2017-05-25

    Developmental pathways that orchestrate the fleeting transition of endothelial cells into haematopoietic stem cells remain undefined. Here we demonstrate a tractable approach for fully reprogramming adult mouse endothelial cells to haematopoietic stem cells (rEC-HSCs) through transient expression of the transcription-factor-encoding genes Fosb, Gfi1, Runx1, and Spi1 (collectively denoted hereafter as FGRS) and vascular-niche-derived angiocrine factors. The induction phase (days 0-8) of conversion is initiated by expression of FGRS in mature endothelial cells, which results in endogenous Runx1 expression. During the specification phase (days 8-20), RUNX1 + FGRS-transduced endothelial cells commit to a haematopoietic fate, yielding rEC-HSCs that no longer require FGRS expression. The vascular niche drives a robust self-renewal and expansion phase of rEC-HSCs (days 20-28). rEC-HSCs have a transcriptome and long-term self-renewal capacity similar to those of adult haematopoietic stem cells, and can be used for clonal engraftment and serial primary and secondary multi-lineage reconstitution, including antigen-dependent adaptive immune function. Inhibition of TGFβ and CXCR7 or activation of BMP and CXCR4 signalling enhanced generation of rEC-HSCs. Pluripotency-independent conversion of endothelial cells into autologous authentic engraftable haematopoietic stem cells could aid treatment of haematological disorders.

  4. Quiescent gastric stem cells maintain the adult Drosophila stomach.

    Science.gov (United States)

    Strand, Marie; Micchelli, Craig A

    2011-10-25

    The adult Drosophila copper cell region or "stomach" is a highly acidic compartment of the midgut with pH stem cells (GSSCs) produces the acid-secreting copper cells, interstitial cells, and enteroendocrine cells of the stomach. Our assays demonstrate that GSSCs are largely quiescent but can be induced to regenerate the gastric epithelium in response to environmental challenge. Finally, genetic analysis reveals that adult GSSC maintenance depends on Wnt signaling. Characterization of the GSSC lineage in Drosophila, with striking similarities to mammals, will advance the study of both homeostatic and pathogenic processes in the stomach.

  5. Angiogenic factors stimulate growth of adult neural stem cells.

    Directory of Open Access Journals (Sweden)

    Andreas Androutsellis-Theotokis

    2010-02-01

    Full Text Available The ability to grow a uniform cell type from the adult central nervous system (CNS is valuable for developing cell therapies and new strategies for drug discovery. The adult mammalian brain is a source of neural stem cells (NSC found in both neurogenic and non-neurogenic zones but difficulties in culturing these hinders their use as research tools.Here we show that NSCs can be efficiently grown in adherent cell cultures when angiogenic signals are included in the medium. These signals include both anti-angiogenic factors (the soluble form of the Notch receptor ligand, Dll4 and pro-angiogenic factors (the Tie-2 receptor ligand, Angiopoietin 2. These treatments support the self renewal state of cultured NSCs and expression of the transcription factor Hes3, which also identifies the cancer stem cell population in human tumors. In an organotypic slice model, angiogenic factors maintain vascular structure and increase the density of dopamine neuron processes.We demonstrate new properties of adult NSCs and a method to generate efficient adult NSC cultures from various central nervous system areas. These findings will help establish cellular models relevant to cancer and regeneration.

  6. Erythroid differentiation of fetal, newborn and adult haemopoietic stem cells

    International Nuclear Information System (INIS)

    Rencricca, N.J.; Howard, D.; Kubanek, B.; Stohlman, F.; Department of Biological Sciences, University of Lowell, Lowell, Massachusetts, USA)

    1976-01-01

    Erythroid regeneration was studied in lethally irradiated mice given transplants containing equivalent numbers of haemopoietic stem cells (i.e. CFU) from fetal liver, neonatal marrow or adult marrow. Adult marrow was taken from normal control mice, whose CFU for the most part were not in active cell cycle, as well as from phenylhydrazine-treated groups whose CFU were in similar state of proliferation (i.e. approximately 40-50% in DNA synthesis) as those derived from fetal liver and neonatal marrow. Splenic and femoral radioiron ( 59 Fe) incorporation were measured at intervals after transplantation and were found to begin earliest in mice given fetal liver, then in animals given neonatal marrow and latest in recipients of adult marrow. Peripheral reticulocytes showed a similar pattern of recovery. The data reported herein suggest that the differences in erythroid regeneration evoked by transplants of fetal liver, neonatal marrow or adult marrow, are not solely attributed to the degree of proliferation in the pluripotential stem cell compartment. These data may, however, suggest a shorter doubling time for cells comprising the fetal and newborn committed erythroid compartments. (author)

  7. Erythroid differentiation of fetal, newborn, and adult haemopoietic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Rencricca, N J; Howard, D; Kubanek, B; Stohlman, F [Boston Univ., Mass. (USA). School of Medicine; Department of Biological Sciences, University of Lowell, Lowell, Massachusetts, USA)

    1976-01-01

    Erythroid regeneration was studied in lethally irradiated mice given transplants containing equivalent numbers of haemopoietic stem cells (i.e. CFU) from fetal liver, neonatal marrow or adult marrow. Adult marrow was taken from normal control mice, whose CFU for the most part were not in active cell cycle, as well as from phenylhydrazine-treated groups whose CFU were in similar state of proliferation (i.e. approximately 40-50% in DNA synthesis) as those derived from fetal liver and neonatal marrow. Splenic and femoral radioiron (/sup 59/Fe) incorporation were measured at intervals after transplantation and were found to begin earliest in mice given fetal liver, then in animals given neonatal marrow and latest in recipients of adult marrow. Peripheral reticulocytes showed a similar pattern of recovery. The data reported herein suggest that the differences in erythroid regeneration evoked by transplants of fetal liver, neonatal marrow or adult marrow, are not solely attributed to the degree of proliferation in the pluripotential stem cell compartment. These data may, however, suggest a shorter doubling time for cells comprising the fetal and newborn committed erythroid compartments.

  8. The C. elegans TPR Containing Protein, TRD-1, Regulates Cell Fate Choice in the Developing Germ Line and Epidermis.

    Directory of Open Access Journals (Sweden)

    Samantha Hughes

    Full Text Available Correct cell fate choice is crucial in development. In post-embryonic development of the hermaphroditic Caenorhabitis elegans, distinct cell fates must be adopted in two diverse tissues. In the germline, stem cells adopt one of three possible fates: mitotic cell cycle, or gamete formation via meiosis, producing either sperm or oocytes. In the epidermis, the stem cell-like seam cells divide asymmetrically, with the daughters taking on either a proliferative (seam or differentiated (hypodermal or neuronal fate. We have isolated a novel conserved C. elegans tetratricopeptide repeat containing protein, TRD-1, which is essential for cell fate determination in both the germline and the developing epidermis and has homologs in other species, including humans (TTC27. We show that trd-1(RNAi and mutant animals have fewer seam cells as a result of inappropriate differentiation towards the hypodermal fate. In the germline, trd-1 RNAi results in a strong masculinization phenotype, as well as defects in the mitosis to meiosis switch. Our data suggests that trd-1 acts downstream of tra-2 but upstream of fem-3 in the germline sex determination pathway, and exhibits a constellation of phenotypes in common with other Mog (masculinization of germline mutants. Thus, trd-1 is a new player in both the somatic and germline cell fate determination machinery, suggestive of a novel molecular connection between the development of these two diverse tissues.

  9. The hair follicle bulge: a niche for adult stem cells.

    Science.gov (United States)

    Pasolli, Hilda Amalia

    2011-08-01

    Adult stem cells (SCs) are essential for tissue homeostasis and wound repair. They have the ability to both self-renew and differentiate into multiple cell types. They often reside in specialized microenvironments or niches that preserve their proliferative and tissue regenerative capacity. The murine hair follicle (HF) has a specialized and permanent compartment--the bulge, which safely lodges SCs and provides the necessary molecular cues to regulate their function. The HF undergoes cyclic periods of destruction, regeneration, and rest, making it an excellent system to study SC biology.

  10. A revisionist history of adult marrow stem cell biology or 'they forgot about the discard'.

    Science.gov (United States)

    Quesenberry, P; Goldberg, L

    2017-08-01

    The adult marrow hematopoietic stem cell biology has largely been based on studies of highly purified stem cells. This is unfortunate because during the stem cell purification the great bulk of stem cells are discarded. These cells are actively proliferating. The final purified stem cell is dormant and not representative of the whole stem cell compartment. Thus, a large number of studies on the cellular characteristics, regulators and molecular details of stem cells have been carried on out of non-represented cells. Niche studies have largely pursued using these purified stem cells and these are largely un-interpretable. Other considerations include the distinction between baseline and transplant stem cells and the modulation of stem cell phenotype by extracellular vesicles, to cite a non-inclusive list. Work needs to proceed on characterizing the true stem cell population.

  11. The longest telomeres: a general signature of adult stem cell compartments

    Science.gov (United States)

    Flores, Ignacio; Canela, Andres; Vera, Elsa; Tejera, Agueda; Cotsarelis, George; Blasco, María A.

    2008-01-01

    Identification of adult stem cells and their location (niches) is of great relevance for regenerative medicine. However, stem cell niches are still poorly defined in most adult tissues. Here, we show that the longest telomeres are a general feature of adult stem cell compartments. Using confocal telomere quantitative fluorescence in situ hybridization (telomapping), we find gradients of telomere length within tissues, with the longest telomeres mapping to the known stem cell compartments. In mouse hair follicles, we show that cells with the longest telomeres map to the known stem cell compartments, colocalize with stem cell markers, and behave as stem cells upon treatment with mitogenic stimuli. Using K15-EGFP reporter mice, which mark hair follicle stem cells, we show that GFP-positive cells have the longest telomeres. The stem cell compartments in small intestine, testis, cornea, and brain of the mouse are also enriched in cells with the longest telomeres. This constitutes the description of a novel general property of adult stem cell compartments. Finally, we make the novel finding that telomeres shorten with age in different mouse stem cell compartments, which parallels a decline in stem cell functionality, suggesting that telomere loss may contribute to stem cell dysfunction with age. PMID:18283121

  12. Catalog of gene expression in adult neural stem cells and their in vivo microenvironment

    International Nuclear Information System (INIS)

    Williams, Cecilia; Wirta, Valtteri; Meletis, Konstantinos; Wikstroem, Lilian; Carlsson, Leif; Frisen, Jonas; Lundeberg, Joakim

    2006-01-01

    Stem cells generally reside in a stem cell microenvironment, where cues for self-renewal and differentiation are present. However, the genetic program underlying stem cell proliferation and multipotency is poorly understood. Transcriptome analysis of stem cells and their in vivo microenvironment is one way of uncovering the unique stemness properties and provides a framework for the elucidation of stem cell function. Here, we characterize the gene expression profile of the in vivo neural stem cell microenvironment in the lateral ventricle wall of adult mouse brain and of in vitro proliferating neural stem cells. We have also analyzed an Lhx2-expressing hematopoietic-stem-cell-like cell line in order to define the transcriptome of a well-characterized and pure cell population with stem cell characteristics. We report the generation, assembly and annotation of 50,792 high-quality 5'-end expressed sequence tag sequences. We further describe a shared expression of 1065 transcripts by all three stem cell libraries and a large overlap with previously published gene expression signatures for neural stem/progenitor cells and other multipotent stem cells. The sequences and cDNA clones obtained within this framework provide a comprehensive resource for the analysis of genes in adult stem cells that can accelerate future stem cell research

  13. Strategies for homeostatic stem cell self-renewal in adult tissues

    NARCIS (Netherlands)

    Simons, B.D.; Clevers, H.

    2011-01-01

    In adult tissues, an exquisite balance exists between stem cell proliferation and the generation of differentiated offspring. Classically, it has been argued that this balance is obtained at the level of a single stem cell, which divides strictly into a new stem cell and a progenitor. However,

  14. Tissue-resident adult stem cell populations of rapidly self-renewing organs

    NARCIS (Netherlands)

    Barker, N.; Bartfeld, S.; Clevers, H.

    2010-01-01

    The epithelial lining of the intestine, stomach, and skin is continuously exposed to environmental assault, imposing a requirement for regular self-renewal. Resident adult stem cell populations drive this renewal, and much effort has been invested in revealing their identity. Reliable adult stem

  15. Axonal Control of the Adult Neural Stem Cell Niche

    Science.gov (United States)

    Tong, Cheuk Ka; Chen, Jiadong; Cebrián-Silla, Arantxa; Mirzadeh, Zaman; Obernier, Kirsten; Guinto, Cristina D.; Tecott, Laurence H.; García-Verdugo, Jose Manuel; Kriegstein, Arnold; Alvarez-Buylla, Arturo

    2014-01-01

    SUMMARY The ventricular-subventricular zone (V-SVZ) is an extensive germinal niche containing neural stem cells (NSC) in the walls of the lateral ventricles of the adult brain. How the adult brain’s neural activity influences the behavior of adult NSCs remains largely unknown. We show that serotonergic (5HT) axons originating from a small group of neurons in the raphe form an extensive plexus on most of the ventricular walls. Electron microscopy revealed intimate contacts between 5HT axons and NSCs (B1) or ependymal cells (E1) and these cells were labeled by a transsynaptic viral tracer injected into the raphe. B1 cells express the 5HT receptors 2C and 5A. Electrophysiology showed that activation of these receptors in B1 cells induced small inward currents. Intraventricular infusion of 5HT2C agonist or antagonist increased or decreased V-SVZ proliferation, respectively. These results indicate that supraependymal 5HT axons directly interact with NSCs to regulate neurogenesis via 5HT2C. PMID:24561083

  16. Adult Mesenchymal Stem Cells: When, Where, and How

    Directory of Open Access Journals (Sweden)

    Arnold I. Caplan

    2015-01-01

    Full Text Available Adult mesenchymal stem cells (MSCs have profound medicinal effects at body sites of tissue injury, disease, or inflammation as either endogenously or exogenously supplied. The medicinal effects are either immunomodulatory or trophic or both. When to deliver these mediators of regeneration, where, and by what delivery apparatus or mechanism will directly determine their medical efficacy. The MSCs help manage the innate regenerative capacity of almost every body tissue and the MSCs have only recently been fully appreciated. Perhaps the most skilled physician-manager of the body’s innate regenerative capacity is in orthopedics where the vigorous regeneration and repair capacity of bone through local MSCs-titers is expertly managed by the orthopaedic physician. The challenge is to extend MSCs expertise to address other tissue dysfunctions and diseases. The medicine of tomorrow will encompass optimizing the tissues’ intrinsic regenerative potential through management of local MSCs.

  17. A functional model for adult stem cells in epithelial tissues.

    NARCIS (Netherlands)

    Verstappen, J.; Katsaros, C.; Torensma, R.; Hoff, J.W. Von den

    2009-01-01

    Tissue turnover, regeneration, and repair take place throughout life. Stem cells are key players in these processes. The characteristics and niches of the stem cell populations in different tissues, and even in related tissues, vary extensively. In this review, stem cell differentiation and stem

  18. Dll1 maintains quiescence of adult neural stem cells and segregates asymmetrically during mitosis.

    Science.gov (United States)

    Kawaguchi, Daichi; Furutachi, Shohei; Kawai, Hiroki; Hozumi, Katsuto; Gotoh, Yukiko

    2013-01-01

    Stem cells often divide asymmetrically to produce one stem cell and one differentiating cell, thus maintaining the stem cell pool. Although neural stem cells (NSCs) in the adult mouse subventricular zone have been suggested to divide asymmetrically, intrinsic cell fate determinants for asymmetric NSC division are largely unknown. Stem cell niches are important for stem cell maintenance, but the niche for the maintenance of adult quiescent NSCs has remained obscure. Here we show that the Notch ligand Delta-like 1 (Dll1) is required to maintain quiescent NSCs in the adult mouse subventricular zone. Dll1 protein is induced in activated NSCs and segregates to one daughter cell during mitosis. Dll1-expressing cells reside in close proximity to quiescent NSCs, suggesting a feedback signal for NSC maintenance by their sister cells and progeny. Our data suggest a model in which NSCs produce their own niche cells for their maintenance through asymmetric Dll1 inheritance at mitosis.

  19. State performance in pluripotent and adult stem cell research, 2009-2016.

    Science.gov (United States)

    Surani, Sana H; Levine, Aaron D

    2018-04-01

    To examine how the geographic distribution of pluripotent and adult stem cell research publications within the USA differs from other areas of biomedical research. Publication count data for pluripotent stem cell research, adult stem cell research and a comparison group representative of biomedical research more broadly were collected and analyzed for each US state from 2009 to 2016. The distribution of pluripotent stem cell research differed from the other fields with overperformance in pluripotent stem cell research observed in California, as well as Wisconsin, Massachusetts, Maryland and Connecticut. Our analysis suggests that permissive state stem cell policy may be one of the several factors contributing to strong state performance in pluripotent stem cell research.

  20. Generation of germ cells in vitro in the era of induced pluripotent stem cells.

    Science.gov (United States)

    Imamura, Masanori; Hikabe, Orie; Lin, Zachary Yu-Ching; Okano, Hideyuki

    2014-01-01

    Induced pluripotent stem cells (iPSCs) are stem cells that can be artificially generated via "cellular reprogramming" using gene transduction in somatic cells. iPSCs have enormous potential in stem-cell biology as they can give rise to numerous cell lineages, including the three germ layers. An evaluation of germ-line competency by blastocyst injection or tetraploid complementation, however, is critical for determining the developmental potential of mouse iPSCs towards germ cells. Recent studies have demonstrated that primordial germ cells obtained by the in vitro differentiation of iPSCs produce functional gametes as well as healthy offspring. These findings illustrate not only that iPSCs are developmentally similar to embryonic stem cells (ESCs), but also that somatic cells from adult tissues can produce gametes in vitro, that is, if they are reprogrammed into iPSCs. In this review, we discuss past and recent advances in the in vitro differentiation of germ cells using pluripotent stem cells, with an emphasis on ESCs and iPSCs. While this field of research is still at a stage of infancy, it holds great promises for investigating the mechanisms of germ-cell development, especially in humans, and for advancing reproductive and developmental engineering technologies in the future. © 2013 Wiley Periodicals, Inc.

  1. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  2. Transcriptional profiling of adult neural stem-like cells from the human brain.

    Directory of Open Access Journals (Sweden)

    Cecilie Jonsgar Sandberg

    Full Text Available There is a great potential for the development of new cell replacement strategies based on adult human neural stem-like cells. However, little is known about the hierarchy of cells and the unique molecular properties of stem- and progenitor cells of the nervous system. Stem cells from the adult human brain can be propagated and expanded in vitro as free floating neurospheres that are capable of self-renewal and differentiation into all three cell types of the central nervous system. Here we report the first global gene expression study of adult human neural stem-like cells originating from five human subventricular zone biopsies (mean age 42, range 33-60. Compared to adult human brain tissue, we identified 1,189 genes that were significantly up- and down-regulated in adult human neural stem-like cells (1% false discovery rate. We found that adult human neural stem-like cells express stem cell markers and have reduced levels of markers that are typical of the mature cells in the nervous system. We report that the genes being highly expressed in adult human neural stem-like cells are associated with developmental processes and the extracellular region of the cell. The calcium signaling pathway and neuroactive ligand-receptor interactions are enriched among the most differentially regulated genes between adult human neural stem-like cells and adult human brain tissue. We confirmed the expression of 10 of the most up-regulated genes in adult human neural stem-like cells in an additional sample set that included adult human neural stem-like cells (n = 6, foetal human neural stem cells (n = 1 and human brain tissues (n = 12. The NGFR, SLITRK6 and KCNS3 receptors were further investigated by immunofluorescence and shown to be heterogeneously expressed in spheres. These receptors could potentially serve as new markers for the identification and characterisation of neural stem- and progenitor cells or as targets for manipulation of cellular

  3. Cerebellar stem cells do not produce neurons and astrocytes in adult mouse

    International Nuclear Information System (INIS)

    Su, Xin; Guan, Wuqiang; Yu, Yong-Chun; Fu, Yinghui

    2014-01-01

    Highlights: • No new neurons and astrocytes are generated in adult mouse cerebellum. • Very few mash1 + or nestin + stem cells exist, and most of them are quiescent. • Cell proliferation rate is diversified among cerebellar regions and decreases over time. - Abstract: Although previous studies implied that cerebellar stem cells exist in some adult mammals, little is known about whether these stem cells can produce new neurons and astrocytes. In this study by bromodeoxyuridine (BrdU) intraperitoneal (i.p.) injection, we found that there are abundant BrdU + cells in adult mouse cerebellum, and their quantity and density decreases significantly over time. We also found cell proliferation rate is diversified in different cerebellar regions. Among these BrdU + cells, very few are mash1 + or nestin + stem cells, and the vast majority of cerebellar stem cells are quiescent. Data obtained by in vivo retrovirus injection indicate that stem cells do not produce neurons and astrocytes in adult mouse cerebellum. Instead, some cells labeled by retrovirus are Iba1 + microglia. These results indicate that very few stem cells exist in adult mouse cerebellum, and none of these stem cells contribute to neurogenesis and astrogenesis under physiological condition

  4. Identification and Characterization of Adult Porcine Muscle Stem Cells

    OpenAIRE

    Wilschut, K.J.

    2009-01-01

    In the past decade, tissue-specific stem cell research has been emerging. Stem cells are characterized by a long-term expansion and a broad developmental potential in vitro. Pre-clinical studies appear promising, but still many limitations have to be overcome before broad therapeutic use of stem cells is save and efficient. Meanwhile, the use of stem cells for drug screening and toxicology studies are also beneficial to biomedical science. To cure muscular dystrophy no efficient therapy exist...

  5. Chick stem cells: Current progress and future prospects

    Science.gov (United States)

    Intarapat, Sittipon; Stern, Claudio D.

    2013-01-01

    Chick embryonic stem cells (cESCs) can be derived from cells obtained from stage X embryos (blastoderm stage); these have the ability to contribute to all somatic lineages in chimaeras, but not to the germ line. However, lines of stem cells that are able to contribute to the germ line can be established from chick primordial germ cells (cPGCs) and embryonic germ cells (cEGCs). This review provides information on avian stem cells, emphasizing different sources of cells and current methods for derivation and culture of pluripotent cells from chick embryos. We also review technologies for isolation and derivation of chicken germ cells and the production of transgenic birds. PMID:24103496

  6. Identification and Characterization of Adult Porcine Muscle Stem Cells

    NARCIS (Netherlands)

    Wilschut, K.J.

    2009-01-01

    In the past decade, tissue-specific stem cell research has been emerging. Stem cells are characterized by a long-term expansion and a broad developmental potential in vitro. Pre-clinical studies appear promising, but still many limitations have to be overcome before broad therapeutic use of stem

  7. The Yin and Yang of chromatin dynamics in adult stem cell fate selection

    Science.gov (United States)

    Adam, Rene C.; Fuchs, Elaine

    2015-01-01

    Adult organisms rely on tissue stem cells for maintenance and repair. During homeostasis, the concerted action of local niche signals and epigenetic regulators establish stable gene expression patterns to ensure that stem cells are not lost over time. However, stem cells also provide host tissues with a remarkable plasticity to respond to perturbations. How adult stem cells choose and acquire new fates is unknown, but the genome-wide mapping of epigenetic landscapes suggests a critical role for chromatin remodeling in these processes. Here, we explore the emerging role of chromatin modifiers and pioneer transcription factors in adult stem cell fate decisions and plasticity, which ensure that selective lineage choices are only made when environmentally cued. PMID:26689127

  8. Physicochemical Control of Adult Stem Cell Differentiation: Shedding Light on Potential Molecular Mechanisms

    Science.gov (United States)

    2010-01-01

    stem - cell -based biomedical and therapeutic applications, including tissue engineering, requires an understanding of the cell-cell and cell-environment interactions. To this end, recent efforts have been focused on the manipulation of adult stem cell differentiation using inductive soluble factors, designing suitable mechanical environments, and applying noninvasive physical forces. Although each of these different approaches has been successfully applied to regulate stem cell differentiation, it would be of great interest and

  9. Evolutionary dynamics of adult stem cells: Comparison of random and immortal strand segregation mechanisms

    OpenAIRE

    Tannenbaum, Emmanuel; Sherley, James L.; Shakhnovich, Eugene I.

    2004-01-01

    This paper develops a point-mutation model describing the evolutionary dynamics of a population of adult stem cells. Such a model may prove useful for quantitative studies of tissue aging and the emergence of cancer. We consider two modes of chromosome segregation: (1) Random segregation, where the daughter chromosomes of a given parent chromosome segregate randomly into the stem cell and its differentiating sister cell. (2) ``Immortal DNA strand'' co-segregation, for which the stem cell reta...

  10. Repair of Tissues by Adult Stem/Progenitor Cells (MSCs): Controversies, Myths, and Changing Paradigms

    OpenAIRE

    Prockop, Darwin J

    2009-01-01

    Research on stem cells has progressed at a rapid pace and, as might be anticipated, the results have generated several controversies, a few myths and a change in a major paradigm. Some of these issues will be reviewed in this study with special emphasis on how they can be applied to the adult stem/progenitor cells from bone marrow, referred to as MSCs.

  11. Relapsing tumefactive lesion in an adult with medulloblastoma previously treated with chemoradiotherapy and stem cell transplant.

    Science.gov (United States)

    Mahta, Ali; Qu, Yan; Nastic, Denis; Sundstrom, Maria; Kim, Ryan Y; Saria, Marlon; Santagata, Sandro; Kesari, Santosh

    2012-04-01

    Herein, we present an adult case of medulloblastoma who received chemotherapy, radiation therapy and stem cell transplantation, and underwent multiple surgical resections for what were thought to be recurrences; however pathology confirmed a diagnosis of relapsing tumefactive lesions. This phenomenon seems to be a consequence of stem cell transplantation rather than a simple radiation treatment effect.

  12. Thyroid hormone regulation of adult intestinal stem cells: Implications on intestinal development and homeostasis.

    Science.gov (United States)

    Sun, Guihong; Roediger, Julia; Shi, Yun-Bo

    2016-12-01

    Organ-specific adult stem cells are essential for organ homeostasis, tissue repair and regeneration. The formation of such stem cells often takes place during postembryonic development, a period around birth in mammals when plasma thyroid hormone concentration is high. The life-long self-renewal of the intestinal epithelium has made mammalian intestine a valuable model to study the function and regulation and adult stem cells. On the other hand, much less is known about how the adult intestinal stem cells are formed during vertebrate development. Here, we will review some recent progresses on this subject, focusing mainly on the formation of the adult intestine during Xenopus metamorphosis. We will discuss the role of thyroid hormone signaling pathway in the process and potential molecular conservations between amphibians and mammals as well as the implications in organ homeostasis and human diseases.

  13. Characterization of multipotent adult progenitor cells, a subpopulation of mesenchymal stem cells.

    Science.gov (United States)

    Reyes, M; Verfaillie, C M

    2001-06-01

    Mesenchymal stem cells were isolated and a subpopulation of cells--multipotent adult progenitor cells--were identified that have the potential for multilineage differentiation. Their ability to engraft and differentiate in vivo is under investigation.

  14. The Chromatin Remodeler BPTF Activates a Stemness Gene-Expression Program Essential for the Maintenance of Adult Hematopoietic Stem Cells.

    Science.gov (United States)

    Xu, Bowen; Cai, Ling; Butler, Jason M; Chen, Dongliang; Lu, Xiongdong; Allison, David F; Lu, Rui; Rafii, Shahin; Parker, Joel S; Zheng, Deyou; Wang, Gang Greg

    2018-03-13

    Self-renewal and differentiation of adult stem cells are tightly regulated partly through configuration of chromatin structure by chromatin remodelers. Using knockout mice, we here demonstrate that bromodomain PHD finger transcription factor (BPTF), a component of the nucleosome remodeling factor (NURF) chromatin-remodeling complex, is essential for maintaining the population size of hematopoietic stem/progenitor cells (HSPCs), including long-term hematopoietic stem cells (HSCs). Bptf-deficient HSCs are defective in reconstituted hematopoiesis, and hematopoietic-specific knockout of Bptf caused profound defects including bone marrow failure and anemia. Genome-wide transcriptome profiling revealed that BPTF loss caused downregulation of HSC-specific gene-expression programs, which contain several master transcription factors (Meis1, Pbx1, Mn1, and Lmo2) required for HSC maintenance and self-renewal. Furthermore, we show that BPTF potentiates the chromatin accessibility of key HSC "stemness" genes. These results demonstrate an essential requirement of the chromatin remodeler BPTF and NURF for activation of "stemness" gene-expression programs and proper function of adult HSCs. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  15. The Chromatin Remodeler BPTF Activates a Stemness Gene-Expression Program Essential for the Maintenance of Adult Hematopoietic Stem Cells

    Directory of Open Access Journals (Sweden)

    Bowen Xu

    2018-03-01

    Full Text Available Summary: Self-renewal and differentiation of adult stem cells are tightly regulated partly through configuration of chromatin structure by chromatin remodelers. Using knockout mice, we here demonstrate that bromodomain PHD finger transcription factor (BPTF, a component of the nucleosome remodeling factor (NURF chromatin-remodeling complex, is essential for maintaining the population size of hematopoietic stem/progenitor cells (HSPCs, including long-term hematopoietic stem cells (HSCs. Bptf-deficient HSCs are defective in reconstituted hematopoiesis, and hematopoietic-specific knockout of Bptf caused profound defects including bone marrow failure and anemia. Genome-wide transcriptome profiling revealed that BPTF loss caused downregulation of HSC-specific gene-expression programs, which contain several master transcription factors (Meis1, Pbx1, Mn1, and Lmo2 required for HSC maintenance and self-renewal. Furthermore, we show that BPTF potentiates the chromatin accessibility of key HSC “stemness” genes. These results demonstrate an essential requirement of the chromatin remodeler BPTF and NURF for activation of “stemness” gene-expression programs and proper function of adult HSCs. : Wang and colleagues show that a chromatin remodeler, BPTF, sustains appropriate functions of hematopoietic stem/progenitor cells (HSPCs. BPTF loss causes bone marrow failure and anemia. The authors further define a BPTF-dependent gene-expression program in HSPCs, which contains key HSC stemness factors. These results demonstrate an essential requirement of the BPTF-associated chromatin remodelers for HSC functionality and adult hematopoiesis. Keywords: Bptf, hematopoietic stem cells, chromatin remodeler, Meis1, Pbx1, Mn1, DNA accessibility, NURF, AP1 complex

  16. Adipose-derived adult stem cells: available technologies for potential clinical regenerative applications in dentistry.

    Science.gov (United States)

    Catalano, Enrico; Cochis, Andrea; Varoni, Elena; Rimondini, Lia; Carrassi, Antonio; Azzimonti, Barbara

    2013-01-01

    Tissue homeostasis depends closely on the activity and welfare of adult stem cells. These cells represent a promising tool for biomedical research since they can aid in treatment and promote the regeneration of damaged organs in many human disorders. Adult stem cells indefinitely preserve their ability to self-renew and differentiate into various phenotypes; this capacity could be promoted in vitro by particular culture conditions (differentiation media) or spontaneously induced in vivo by exploiting the biochemical and mechanical properties of the tissue in which the stem cells are implanted. Among the different sources of adult stem cells, adipose tissue is an attractive possibility thanks to its ready availability and the standard extraction techniques at our disposal today. This review discusses the isolation, characterization, and differentiation of human adipose-derived adult stem cells, as well as regeneration strategies, therapeutic uses, and adverse effects of their delivery. In particular, since oral disorders (e.g., trauma, erosion, and chronic periodontitis) often cause the loss of dental tissue along with functional, phonetic, and aesthetic impairment, this review focuses on the application of human adipose-derived adult stem cells, alone or in combination with biomaterials, in treating oral diseases.

  17. Wnt/β-catenin signaling in adult mammalian epithelial stem cells

    NARCIS (Netherlands)

    Kretzschmar, Kai; Clevers, Hans

    2017-01-01

    Adult stem cells self-renew and replenish differentiated cells in various organs and tissues throughout a mammal's life. Over the last 25 years an ever-growing body of knowledge has unraveled the essential regulation of adult mammalian epithelia by the canonical Wnt signaling with its key

  18. Adult Tissue-Derived Stem Cells and Tolerance Induction in Nonhuman Primates for Vascularized Composite Allograft Transplantation

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-16-2-0042 TITLE: Adult Tissue-Derived Stem Cells and Tolerance Induction in Nonhuman Primates for Vascularized Composite...2017 2. REPORT TYPE Annual 3. DATES COVERED 30 Sep 2016 - 29 Sep 2017 4. TITLE AND SUBTITLE Adult Tissue-Derived Stem Cells and Tolerance Induction...Distribution Unlimited 13. SUPPLEMENTARY NOTES The utilization of adult derived adipose stem cells administration in composite tissue transplantation

  19. Molecular characterization and expression profile of nanos in Schistosoma japonicum and its influence on the expression several mammalian stem cell factors.

    Science.gov (United States)

    Giri, Bikash Ranjan; Du, Xiaoli; Xia, Tianqi; Chen, Yongjun; Li, Hao; Cheng, Guofeng

    2017-07-01

    Pluripotent stem cells, called neoblasts, are well known for the regenerative capability and developmental plasticity in flatworms. Impressive advancement has been made in free-living flatworms, while in case of its parasitic counterpart, neoblast-like stem cells have attracted recent attention for its self-renewal and differentiation capacity. Nanos is a key conserved post-transcriptional regulator critical for the formation, development, and/or maintenance of the pluripotent germ line stem cell systems in many metazoans including schistosomes. In the present study, we report the molecular cloning and expression of nanos orthologous genes nanos in Schistosoma japonicum (Sjnanos). The cDNA of Sjnanos is 826 bp long, containing an open reading frame (ORF) for 223 amino acid long protein. qRT-PCR analysis shown that Sjnanos was differently expressed in several stages of schistosomes with relatively high level in schistosomula. Additionally, Sjnanos was expressed highly in adult females compared to adult males. Transfection of recombinant plasmid for expressing Sjnanos resulted in significant proliferation and increased expression of several stem cell factors in mammalian cells. Overall, our preliminary study provides the molecular basis to further functionally characterize Sjnanos in S. japonicum.

  20. DAF-18/PTEN signals through AAK-1/AMPK to inhibit MPK-1/MAPK in feedback control of germline stem cell proliferation.

    Directory of Open Access Journals (Sweden)

    Patrick Narbonne

    2017-04-01

    Full Text Available Under replete growth conditions, abundant nutrient uptake leads to the systemic activation of insulin/IGF-1 signalling (IIS and the promotion of stem cell growth/proliferation. Activated IIS can stimulate the ERK/MAPK pathway, the activation of which also supports optimal stem cell proliferation in various systems. Stem cell proliferation rates can further be locally refined to meet the resident tissue's need for differentiated progeny. We have recently shown that the accumulation of mature oocytes in the C. elegans germ line, through DAF-18/PTEN, inhibits adult germline stem cell (GSC proliferation, despite high systemic IIS activation. We show here that this feedback occurs through a novel cryptic signalling pathway that requires PAR-4/LKB1, AAK-1/AMPK and PAR-5/14-3-3 to inhibit the activity of MPK-1/MAPK, antagonize IIS, and inhibit both GSC proliferation and the production of additional oocytes. Interestingly, our results imply that DAF-18/PTEN, through PAR-4/LKB1, can activate AAK-1/AMPK in the absence of apparent energy stress. As all components are conserved, similar signalling cascades may regulate stem cell activities in other organisms and be widely implicated in cancer.

  1. Typography manipulations can affect priming of word stem completion in older and younger adults.

    Science.gov (United States)

    Gibson, J M; Brooks, J O; Friedman, L; Yesavage, J A

    1993-12-01

    The experiments reported here investigated whether changes of typography affected priming of word stem completion performance in older and younger adults. Across all experiments, the typeface in which a word appeared at presentation either did or did not match that of its 3-letter stem at test. In Experiment 1, no significant evidence of a typography effect was found when words were presented with a sentence judgment or letter judgment task. However, subsequent experiments revealed that, in both older and younger adults, only words presented with a syllable judgment task gave rise to the typography effect (Experiments 2-4). Specifically, performance was greater, when the presentation and test typeface matched than when they did not. Experiment 5, which used stem-cued recall, did not reveal a difference between syllable and letter judgment tasks. These findings highlight the complex nature of word stem completion performance.

  2. Endothelial juxtaposition of distinct adult stem cells activates angiogenesis signaling molecules in endothelial cells.

    Science.gov (United States)

    Mohammadi, Elham; Nassiri, Seyed Mahdi; Rahbarghazi, Reza; Siavashi, Vahid; Araghi, Atefeh

    2015-12-01

    Efficacy of therapeutic angiogenesis needs a comprehensive understanding of endothelial cell (EC) function and biological factors and cells that interplay with ECs. Stem cells are considered the key components of pro- and anti-angiogenic milieu in a wide variety of physiopathological states, and interactions of EC-stem cells have been the subject of controversy in recent years. In this study, the potential effects of three tissue-specific adult stem cells, namely rat marrow-derived mesenchymal stem cells (rBMSCs), rat adipose-derived stem cells (rADSCs) and rat muscle-derived satellite cells (rSCs), on the endothelial activation of key angiogenic signaling molecules, including VEGF, Ang-2, VEGFR-2, Tie-2, and Tie2-pho, were investigated. Human umbilical vein endothelial cells (HUVECs) and rat lung microvascular endothelial cells (RLMECs) were cocultured with the stem cells or incubated with the stem cell-derived conditioned media on Matrigel. Following HUVEC-stem cell coculture, CD31-positive ECs were flow sorted and subjected to western blotting to analyze potential changes in the expression of the pro-angiogenic signaling molecules. Elongation and co-alignment of the stem cells were seen along the EC tubes in the EC-stem cell cocultures on Matrigel, with cell-to-cell dye communication in the EC-rBMSC cocultures. Moreover, rBMSCs and rADSCs significantly improved endothelial tubulogenesis in both juxtacrine and paracrine manners. These two latter stem cells dynamically up-regulated VEGF, Ang-2, VREGR-2, and Tie-2 but down-regulated Tie2-pho and the Tie2-pho/Tie-2 ratio in HUVECs. Induction of pro-angiogenic signaling in ECs by marrow- and adipose-derived MSCs further indicates the significance of stem cell milieu in angiogenesis dynamics.

  3. Evidence for a stem cell hierarchy in the adult human breast

    DEFF Research Database (Denmark)

    Villadsen, René; Fridriksdottir, Agla J; Rønnov-Jessen, Lone

    2007-01-01

    Cellular pathways that contribute to adult human mammary gland architecture and lineages have not been previously described. In this study, we identify a candidate stem cell niche in ducts and zones containing progenitor cells in lobules. Putative stem cells residing in ducts were essentially...... in laminin-rich extracellular matrix gels. Staining for the lineage markers keratins K14 and K19 further revealed multipotent cells in the stem cell zone and three lineage-restricted cell types outside this zone. Multiparameter cell sorting and functional characterization with reference to anatomical sites...

  4. Epithelial-mesenchymal transition transcription factors control pluripotent adult stem cell migration in vivo in planarians

    Science.gov (United States)

    Abnave, Prasad; Aboukhatwa, Ellen; Kosaka, Nobuyoshi; Thompson, James; Hill, Mark A.

    2017-01-01

    Migration of stem cells underpins the physiology of metazoan animals. For tissues to be maintained, stem cells and their progeny must migrate and differentiate in the correct positions. This need is even more acute after tissue damage by wounding or pathogenic infection. Inappropriate migration also underpins metastasis. Despite this, few mechanistic studies address stem cell migration during repair or homeostasis in adult tissues. Here, we present a shielded X-ray irradiation assay that allows us to follow stem cell migration in planarians. We demonstrate the use of this system to study the molecular control of stem cell migration and show that snail-1, snail-2 and zeb-1 EMT transcription factor homologs are necessary for cell migration to wound sites and for the establishment of migratory cell morphology. We also observed that stem cells undergo homeostatic migration to anterior regions that lack local stem cells, in the absence of injury, maintaining tissue homeostasis. This requires the polarity determinant notum. Our work establishes planarians as a suitable model for further in-depth study of the processes controlling stem cell migration in vivo. PMID:28893948

  5. Epithelial-mesenchymal transition transcription factors control pluripotent adult stem cell migration in vivo in planarians.

    Science.gov (United States)

    Abnave, Prasad; Aboukhatwa, Ellen; Kosaka, Nobuyoshi; Thompson, James; Hill, Mark A; Aboobaker, A Aziz

    2017-10-01

    Migration of stem cells underpins the physiology of metazoan animals. For tissues to be maintained, stem cells and their progeny must migrate and differentiate in the correct positions. This need is even more acute after tissue damage by wounding or pathogenic infection. Inappropriate migration also underpins metastasis. Despite this, few mechanistic studies address stem cell migration during repair or homeostasis in adult tissues. Here, we present a shielded X-ray irradiation assay that allows us to follow stem cell migration in planarians. We demonstrate the use of this system to study the molecular control of stem cell migration and show that snail-1 , snail-2 and zeb-1 EMT transcription factor homologs are necessary for cell migration to wound sites and for the establishment of migratory cell morphology. We also observed that stem cells undergo homeostatic migration to anterior regions that lack local stem cells, in the absence of injury, maintaining tissue homeostasis. This requires the polarity determinant notum Our work establishes planarians as a suitable model for further in-depth study of the processes controlling stem cell migration in vivo . © 2017. Published by The Company of Biologists Ltd.

  6. Characterization of TLX expression in neural stem cells and progenitor cells in adult brains.

    Directory of Open Access Journals (Sweden)

    Shengxiu Li

    Full Text Available 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.

  7. Characterization of TLX expression in neural stem cells and progenitor cells in adult brains.

    Science.gov (United States)

    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.

  8. Expression and function of orphan nuclear receptor TLX in adult neural stem cells.

    Science.gov (United States)

    Shi, Yanhong; Chichung Lie, D; Taupin, Philippe; Nakashima, Kinichi; Ray, Jasodhara; Yu, Ruth T; Gage, Fred H; Evans, Ronald M

    2004-01-01

    The finding of neurogenesis in the adult brain led to the discovery of adult neural stem cells. TLX was initially identified as an orphan nuclear receptor expressed in vertebrate forebrains and is highly expressed in the adult brain. The brains of TLX-null mice have been reported to have no obvious defects during embryogenesis; however, mature mice suffer from retinopathies, severe limbic defects, aggressiveness, reduced copulation and progressively violent behaviour. Here we show that TLX maintains adult neural stem cells in an undifferentiated, proliferative state. We show that TLX-expressing cells isolated by fluorescence-activated cell sorting (FACS) from adult brains can proliferate, self-renew and differentiate into all neural cell types in vitro. By contrast, TLX-null cells isolated from adult mutant brains fail to proliferate. Reintroducing TLX into FACS-sorted TLX-null cells rescues their ability to proliferate and to self-renew. In vivo, TLX mutant mice show a loss of cell proliferation and reduced labelling of nestin in neurogenic areas in the adult brain. TLX can silence glia-specific expression of the astrocyte marker GFAP in neural stem cells, suggesting that transcriptional repression may be crucial in maintaining the undifferentiated state of these cells.

  9. Human intestinal tissue with adult stem cell properties derived from pluripotent stem cells

    NARCIS (Netherlands)

    Forster, Ryan; Chiba, Kunitoshi; Schaeffer, Lorian; Regalado, Samuel G; Lai, Christine S; Gao, Qing; Kiani, Samira; Farin, Henner F; Clevers, Hans; Cost, Gregory J; Chan, Andy; Rebar, Edward J; Urnov, Fyodor D; Gregory, Philip D; Pachter, Lior; Jaenisch, Rudolf; Hockemeyer, Dirk

    2014-01-01

    Genetically engineered human pluripotent stem cells (hPSCs) have been proposed as a source for transplantation therapies and are rapidly becoming valuable tools for human disease modeling. However, many applications are limited due to the lack of robust differentiation paradigms that allow for the

  10. Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling

    International Nuclear Information System (INIS)

    Das, Ani V.; Zhao Xing; James, Jackson; Kim, Min; Cowan, Kenneth H.; Ahmad, Iqbal

    2006-01-01

    The identification of neural stem cells with retinal potential in the ciliary epithelium (CE) of the adult mammals is of considerable interest because of their potential for replacing or rescuing degenerating retinal neurons in disease or injury. The evaluation of such a potential requires characterization of these cells with regard to their phenotypic properties, potential, and regulatory mechanisms. Here, we demonstrate that rat CE stem cells/progenitors in neurosphere culture display astrocytic nature in terms of expressing glial intermediate neurofilament protein, GFAP. The GFAP-expressing CE stem cells/progenitors form neurospheres in proliferating conditions and generate neurons when shifted to differentiating conditions. These cells express components of the canonical Wnt pathway and its activation promotes their proliferation. Furthermore, we demonstrate that the activation of the canonical Wnt pathway influences neuronal differentiation of CE stem cells/progenitors in a context dependent manner. Our observations suggest that CE stem cells/progenitors share phenotypic properties and regulatory mechanism(s) with neural stem cells elsewhere in the adult CNS

  11. Treatment of radioinduced skin burns by adult stem cells

    International Nuclear Information System (INIS)

    Lataillade, J.J.; Prat, M.; Gourmelon, P.; Bey, E.

    2009-01-01

    In the area of skin injuries caused by ionizing radiations; the recent opportunity give us the the possibility to manage victims of radiation accidents with skin acute symptoms of irradiation. The approach of cell therapy developed for these patients could be in a second time, used for other types of injuries as thermal burns and the injuries linked to overexposure in radiotherapy. In spite of the diversity of approaches of allogeneic and autologous transplantation, the prognosis of deep and extended radioinduced burns is not completely satisfying because of inflammatory recurrences, origin of graft failures. The stem cells have been used in association. The stem cells were got from sampling of autologous bone marrow after an expansion in vitro from 15 to 17 days. The cultures were realised in medium with 8% of platelet lysate (clinical grade). The cells have been given by injection in complement of epidermis auto graft. A spectacular effect was noticed the day after the injection, but disappearing in some days encouraging to realize supplementary injections. An effect of the quickness and the quality of the graft success is appeared significant too. no necrosis recurrence for the patients after four years for the first one of them. We think that the stem cells participate to the local control of inflammation. (N.C.)

  12. Identification of multipotent stem cells from adult dog periodontal ligament.

    Science.gov (United States)

    Wang, Wen-Jun; Zhao, Yu-Ming; Lin, Bi-Chen; Yang, Jie; Ge, Li-Hong

    2012-08-01

    Periodontal diseases, which are characterized by destruction of the connective tissues responsible for restraining the teeth within the jaw, are the main cause of tooth loss. Periodontal regeneration mediated by human periodontal ligament stem cells (hPDLSCs) may offer an alternative strategy for the treatment of periodontal disease. Dogs are a widely used large-animal model for the study of periodontal-disease progression, tissue regeneration, and dental implants, but little attention has been paid to the identification of the cells involved in this species. This study aimed to characterize stem cells isolated from canine periodontal ligament (cPDLSCs). The cPDLSCs, like hPDLSCs, showed clonogenic capability and expressed the mesenchymal stem cell markers STRO-1, CD146, and CD105, but not CD34. After induction of osteogenesis, cPDLSCs showed calcium accumulation in vitro. Moreover, cPDLSCs also showed both adipogenic and chondrogenic potential. Compared with cell-free controls, more cementum/periodontal ligament-like structures were observed in CB-17/SCID mice into which cPDLSCs had been transplanted. These results suggest that cPDLSCs are clonogenic, highly proliferative, and have multidifferentiation potential, and that they could be used as a new cellular therapeutic approach to facilitate successful and more predictable regeneration of periodontal tissue using a canine model of periodontal disease. © 2012 Eur J Oral Sci.

  13. Synergic Functions of miRNAs Determine Neuronal Fate of Adult Neural Stem Cells

    Directory of Open Access Journals (Sweden)

    Meritxell Pons-Espinal

    2017-04-01

    Full Text Available Summary: Adult neurogenesis requires the precise control of neuronal versus astrocyte lineage determination in neural stem cells. While microRNAs (miRNAs are critically involved in this step during development, their actions in adult hippocampal neural stem cells (aNSCs has been unclear. As entry point to address that question we chose DICER, an endoribonuclease essential for miRNA biogenesis and other RNAi-related processes. By specific ablation of Dicer in aNSCs in vivo and in vitro, we demonstrate that miRNAs are required for the generation of new neurons, but not astrocytes, in the adult murine hippocampus. Moreover, we identify 11 miRNAs, of which 9 have not been previously characterized in neurogenesis, that determine neurogenic lineage fate choice of aNSCs at the expense of astrogliogenesis. Finally, we propose that the 11 miRNAs sustain adult hippocampal neurogenesis through synergistic modulation of 26 putative targets from different pathways. : In this article, the authors demonstrate that Dicer-dependent miRNAs are required for the generation of new neurons, but not astrocytes, in the adult hippocampus in vivo and in vitro. The authors identify a new set of 11 miRNAs that synergistically converge on multiple targets in different pathways to sustain neurogenic lineage fate commitment in aNSCs. Keywords: mouse, hippocampus, neural stem cells, fate choice, adult neurogenesis, astrogliogenesis, DICER, microRNAs, synergy

  14. The novel steroidal alkaloids dendrogenin A and B promote proliferation of adult neural stem cells

    International Nuclear Information System (INIS)

    Khalifa, Shaden A.M.; Medina, Philippe de; Erlandsson, Anna; El-Seedi, Hesham R.; Silvente-Poirot, Sandrine; Poirot, Marc

    2014-01-01

    Highlights: • Dendrogenin A and B are new aminoalkyl oxysterols. • Dendrogenins stimulated neural stem cells proliferation. • Dendrogenins induce neuronal outgrowth from neurospheres. • Dendrogenins provide new therapeutic options for neurodegenerative disorders. - Abstract: Dendrogenin A (DDA) and dendrogenin B (DDB) are new aminoalkyl oxysterols which display re-differentiation of tumor cells of neuronal origin at nanomolar concentrations. We analyzed the influence of dendrogenins on adult mice neural stem cell proliferation, sphere formation and differentiation. DDA and DDB were found to have potent proliferative effects in neural stem cells. Additionally, they induce neuronal outgrowth from neurospheres during in vitro cultivation. Taken together, our results demonstrate a novel role for dendrogenins A and B in neural stem cell proliferation and differentiation which further increases their likely importance to compensate for neuronal cell loss in the brain

  15. The novel steroidal alkaloids dendrogenin A and B promote proliferation of adult neural stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Khalifa, Shaden A.M., E-mail: shaden.khalifa@ki.se [Department of Neuroscience, Karolinska Institute, Stockholm (Sweden); Medina, Philippe de [Affichem, Toulouse (France); INSERM UMR 1037, Team “Sterol Metabolism and Therapeutic Innovations in Oncology”, Cancer Research Center of Toulouse, F-31052 Toulouse (France); Erlandsson, Anna [Department of Public Health and Caring Sciences, Uppsala University, Uppsala (Sweden); El-Seedi, Hesham R. [Department of Medicinal Chemistry, Biomedical Centre, Uppsala University, Uppsala (Sweden); Silvente-Poirot, Sandrine [INSERM UMR 1037, Team “Sterol Metabolism and Therapeutic Innovations in Oncology”, Cancer Research Center of Toulouse, F-31052 Toulouse (France); University of Toulouse III, Toulouse (France); Institut Claudius Regaud, Toulouse (France); Poirot, Marc, E-mail: marc.poirot@inserm.fr [INSERM UMR 1037, Team “Sterol Metabolism and Therapeutic Innovations in Oncology”, Cancer Research Center of Toulouse, F-31052 Toulouse (France); University of Toulouse III, Toulouse (France); Institut Claudius Regaud, Toulouse (France)

    2014-04-11

    Highlights: • Dendrogenin A and B are new aminoalkyl oxysterols. • Dendrogenins stimulated neural stem cells proliferation. • Dendrogenins induce neuronal outgrowth from neurospheres. • Dendrogenins provide new therapeutic options for neurodegenerative disorders. - Abstract: Dendrogenin A (DDA) and dendrogenin B (DDB) are new aminoalkyl oxysterols which display re-differentiation of tumor cells of neuronal origin at nanomolar concentrations. We analyzed the influence of dendrogenins on adult mice neural stem cell proliferation, sphere formation and differentiation. DDA and DDB were found to have potent proliferative effects in neural stem cells. Additionally, they induce neuronal outgrowth from neurospheres during in vitro cultivation. Taken together, our results demonstrate a novel role for dendrogenins A and B in neural stem cell proliferation and differentiation which further increases their likely importance to compensate for neuronal cell loss in the brain.

  16. Fetal programming of adult Leydig cell function by androgenic effects on stem/progenitor cells.

    Science.gov (United States)

    Kilcoyne, Karen R; Smith, Lee B; Atanassova, Nina; Macpherson, Sheila; McKinnell, Chris; van den Driesche, Sander; Jobling, Matthew S; Chambers, Thomas J G; De Gendt, Karel; Verhoeven, Guido; O'Hara, Laura; Platts, Sophie; Renato de Franca, Luiz; Lara, Nathália L M; Anderson, Richard A; Sharpe, Richard M

    2014-05-06

    Fetal growth plays a role in programming of adult cardiometabolic disorders, which in men, are associated with lowered testosterone levels. Fetal growth and fetal androgen exposure can also predetermine testosterone levels in men, although how is unknown, because the adult Leydig cells (ALCs) that produce testosterone do not differentiate until puberty. To explain this conundrum, we hypothesized that stem cells for ALCs must be present in the fetal testis and might be susceptible to programming by fetal androgen exposure during masculinization. To address this hypothesis, we used ALC ablation/regeneration to identify that, in rats, ALCs derive from stem/progenitor cells that express chicken ovalbumin upstream promoter transcription factor II. These stem cells are abundant in the fetal testis of humans and rodents, and lineage tracing in mice shows that they develop into ALCs. The stem cells also express androgen receptors (ARs). Reduction in fetal androgen action through AR KO in mice or dibutyl phthalate (DBP) -induced reduction in intratesticular testosterone in rats reduced ALC stem cell number by ∼40% at birth to adulthood and induced compensated ALC failure (low/normal testosterone and elevated luteinizing hormone). In DBP-exposed males, this failure was probably explained by reduced testicular steroidogenic acute regulatory protein expression, which is associated with increased histone methylation (H3K27me3) in the proximal promoter. Accordingly, ALCs and ALC stem cells immunoexpressed increased H3K27me3, a change that was also evident in ALC stem cells in fetal testes. These studies highlight how a key component of male reproductive development can fundamentally reprogram adult hormone production (through an epigenetic change), which might affect lifetime disease risk.

  17. Identification and characterization of adult mouse meniscus stem/progenitor cells.

    Science.gov (United States)

    Gamer, Laura W; Shi, Rui Rui; Gendelman, Ashira; Mathewson, Dylan; Gamer, Jackson; Rosen, Vicki

    Meniscal damage is a common problem that accelerates the onset of knee osteoarthritis. Stem cell-based tissue engineering treatment approaches have shown promise in preserving meniscal tissue and restoring meniscal function. The purpose of our study was to identify meniscus-derived stem/progenitor cells (MSPCs) from mouse, a model system that allows for in vivo analysis of the mechanisms underlying meniscal injury and healing. MSPCs were isolated from murine menisci grown in explant culture and characterized for stem cell properties. Flow cytometry was used to detect the presence of surface antigens related to stem cells, and qRT-PCR was used to examine the gene expression profile of MSPCs. Major proteins associated with MSPCs were localized in the adult mouse knee using immunohistochemistry. Our data show that MSPCs have universal stem cell-like properties including clonogenicity and multi-potentiality. MSPCs expressed the mesenchymal stem cell markers CD44, Sca-1, CD90, and CD73 and when cultured had elevated levels of biglycan and collagen type I, important extracellular matrix components of adult meniscus. MSPC also expressed significant levels of Lox and Igf-1, genes associated with the embryonic meniscus. Localization studies showed staining for these same proteins in the superficial and outer zones of the adult mouse meniscus, regions thought to harbor endogenous repair cells. MSPCs represent a novel resident stem cell population in the murine meniscus. Analysis of MSPCs in mice will allow for a greater understanding of the cell biology of the meniscus, essential information for enhancing therapeutic strategies for treating knee joint injury and disease.

  18. Gene regulation in adult neural stem cells : Current challenges and possible applications

    NARCIS (Netherlands)

    Encinas, J.M.; Fitzsimons, C.P.

    2017-01-01

    Adult neural stem and progenitor cells (NSPCs) offer a unique opportunity for neural regeneration and niche modification in physiopathological conditions, harnessing the capability to modify from neuronal circuits to glial scar. Findings exposing the vast plasticity and potential of NSPCs have

  19. Identification and characterization of putative stem cells in the adult pig ovary.

    Science.gov (United States)

    Bui, Hong-Thuy; Van Thuan, Nguyen; Kwon, Deug-Nam; Choi, Yun-Jung; Kang, Min-Hee; Han, Jae-Woong; Kim, Teoan; Kim, Jin-Hoi

    2014-06-01

    Recently, the concept of 'neo-oogenesis' has received increasing attention, since it was shown that adult mammals have a renewable source of eggs. The purpose of this study was to elucidate the origin of these eggs and to confirm whether neo-oogenesis continues throughout life in the ovaries of the adult mammal. Adult female pigs were utilized to isolate, identify and characterize, including their proliferation and differentiation capabilities, putative stem cells (PSCs) from the ovary. PSCs were found to comprise a heterogeneous population based on c-kit expression and cell size, and also express stem and germ cell markers. Analysis of PSC molecular progression during establishment showed that these cells undergo cytoplasmic-to-nuclear translocation of Oct4 in a manner reminiscent of gonadal primordial germ cells (PGCs). Hence, cells with the characteristics of early PGCs are present or are generated in the adult pig ovary. Furthermore, the in vitro establishment of porcine PSCs required the presence of ovarian cell-derived extracellular regulatory factors, which are also likely to direct stem cell niche interactions in vivo. In conclusion, the present work supports a crucial role for c-kit and kit ligand/stem cell factor in stimulating the growth, proliferation and nuclear reprogramming of porcine PSCs, and further suggests that porcine PSCs might be the culture equivalent of early PGCs. © 2014. Published by The Company of Biologists Ltd.

  20. Embryonic stem cell-like cells derived from adult human testis

    NARCIS (Netherlands)

    Mizrak, S. C.; Chikhovskaya, J. V.; Sadri-Ardekani, H.; van Daalen, S.; Korver, C. M.; Hovingh, S. E.; Roepers-Gajadien, H. L.; Raya, A.; Fluiter, K.; de Reijke, Th M.; de la Rosette, J. J. M. C. H.; Knegt, A. C.; Belmonte, J. C.; van der Veen, F.; de rooij, D. G.; Repping, S.; van Pelt, A. M. M.

    2010-01-01

    Given the significant drawbacks of using human embryonic stem (hES) cells for regenerative medicine, the search for alternative sources of multipotent cells is ongoing. Studies in mice have shown that multipotent ES-like cells can be derived from neonatal and adult testis. Here we report the

  1. Chondrogenesis of adipose-derived adult stem cells in a poly-lactide-co-glycolide scaffold

    DEFF Research Database (Denmark)

    Mehlhorn, Alexander T; Zwingmann, Jorn; Finkenzeller, Guenter

    2009-01-01

    Adult adipose-derived stem cells (ASCs) are considered to be an alternative cell source for cell-based cartilage repair because of their multiple differentiation potentials. This article addresses the chondrogenic differentiation of ASCs seeded into poly-lactide-co-glycolide (PLGA) scaffolds after...

  2. A role for adult TLX-positive neural stem cells in learning and behaviour.

    Science.gov (United States)

    Zhang, Chun-Li; Zou, Yuhua; He, Weimin; Gage, Fred H; Evans, Ronald M

    2008-02-21

    Neurogenesis persists in the adult brain and can be regulated by a plethora of external stimuli, such as learning, memory, exercise, environment and stress. Although newly generated neurons are able to migrate and preferentially incorporate into the neural network, how these cells are molecularly regulated and whether they are required for any normal brain function are unresolved questions. The adult neural stem cell pool is composed of orphan nuclear receptor TLX-positive cells. Here, using genetic approaches in mice, we demonstrate that TLX (also called NR2E1) regulates adult neural stem cell proliferation in a cell-autonomous manner by controlling a defined genetic network implicated in cell proliferation and growth. Consequently, specific removal of TLX from the adult mouse brain through inducible recombination results in a significant reduction of stem cell proliferation and a marked decrement in spatial learning. In contrast, the resulting suppression of adult neurogenesis does not affect contextual fear conditioning, locomotion or diurnal rhythmic activities, indicating a more selective contribution of newly generated neurons to specific cognitive functions.

  3. Evolutionary dynamics of adult stem cells: comparison of random and immortal-strand segregation mechanisms.

    Science.gov (United States)

    Tannenbaum, Emmanuel; Sherley, James L; Shakhnovich, Eugene I

    2005-04-01

    This paper develops a point-mutation model describing the evolutionary dynamics of a population of adult stem cells. Such a model may prove useful for quantitative studies of tissue aging and the emergence of cancer. We consider two modes of chromosome segregation: (1) random segregation, where the daughter chromosomes of a given parent chromosome segregate randomly into the stem cell and its differentiating sister cell and (2) "immortal DNA strand" co-segregation, for which the stem cell retains the daughter chromosomes with the oldest parent strands. Immortal strand co-segregation is a mechanism, originally proposed by [Cairns Nature (London) 255, 197 (1975)], by which stem cells preserve the integrity of their genomes. For random segregation, we develop an ordered strand pair formulation of the dynamics, analogous to the ordered strand pair formalism developed for quasispecies dynamics involving semiconservative replication with imperfect lesion repair (in this context, lesion repair is taken to mean repair of postreplication base-pair mismatches). Interestingly, a similar formulation is possible with immortal strand co-segregation, despite the fact that this segregation mechanism is age dependent. From our model we are able to mathematically show that, when lesion repair is imperfect, then immortal strand co-segregation leads to better preservation of the stem cell lineage than random chromosome segregation. Furthermore, our model allows us to estimate the optimal lesion repair efficiency for preserving an adult stem cell population for a given period of time. For human stem cells, we obtain that mispaired bases still present after replication and cell division should be left untouched, to avoid potentially fixing a mutation in both DNA strands.

  4. Identifying endogenous neural stem cells in the adult brain in vitro and in vivo: novel approaches.

    Science.gov (United States)

    Rueger, Maria Adele; Androutsellis-Theotokis, Andreas

    2013-01-01

    In the 1960s, Joseph Altman reported that the adult mammalian brain is capable of generating new neurons. Today it is understood that some of these neurons are derived from uncommitted cells in the subventricular zone lining the lateral ventricles, and the dentate gyrus of the hippocampus. The first area generates new neuroblasts which migrate to the olfactory bulb, whereas hippocampal neurogenesis seems to play roles in particular types of learning and memory. A part of these uncommitted (immature) cells is able to divide and their progeny can generate all three major cell types of the nervous system: neurons, astrocytes, and oligodendrocytes; these properties define such cells as neural stem cells. Although the roles of these cells are not yet clear, it is accepted that they affect functions including olfaction and learning/memory. Experiments with insults to the central nervous system also show that neural stem cells are quickly mobilized due to injury and in various disorders by proliferating, and migrating to injury sites. This suggests a role of endogenous neural stem cells in disease. New pools of stem cells are being discovered, suggesting an even more important role for these cells. To understand these cells and to coax them to contribute to tissue repair it would be very useful to be able to image them in the living organism. Here we discuss advances in imaging approaches as well as new concepts that emerge from stem cell biology with emphasis on the interface between imaging and stem cells.

  5. Evaluation of Hematopoietic Stem Cell Mobilization Rates with Early Plerixafor Administration for Adult Stem Cell Transplantation.

    Science.gov (United States)

    Stover, Jessica T; Shaw, J Ryan; Kuchibhatla, Maragatha; Horwitz, Mitchell E; Engemann, Ashley M

    2017-08-01

    The addition of plerixafor to high-dose colony-stimulating growth factor has been shown to improve stem cell mobilization rates in autologous transplant patients with multiple myeloma and non-Hodgkin lymphoma. This study evaluates the change in administration time of plerixafor to determine if cell mobilization rates are similar between the US Food and Drug Administration-approved administration time of 11 hours before apheresis and an earlier administration time of 16 hours before apheresis. Medical records of patients age ≥ 18 years undergoing autologous stem cell transplantation requiring the use of plerixafor after at least 4 days of granulocyte colony-stimulating factor therapy to complete stem cell mobilization from January 1, 2010 through September 30, 2014 were retrospectively reviewed. The primary outcome was CD34 + cell mobilization success rates when plerixafor was administered 11 ± 2 hours (standard administration group) compared with 16 ± 2 hours before cell apheresis (early administration group), as defined as collection of  ≥2 × 10 6 CD34 + cells/kg. Secondary outcomes included the number of plerixafor therapy days required to collect a total of ≥2 × 10 6 CD34 + cells/kg, the number of apheresis cycles required to achieve ≥2 × 10 6 CD34 + cells/kg, the median CD34 + cells/kg collected in each apheresis session, and the rates of reported adverse events that occurred in the standard administration time group compared with the early administration time group. Of the 197 patients included, 114 patients received plerixafor 11 ± 2 hours before apheresis and 83 patients received plerixafor 16 hours ± 2 hours before apheresis. Ninety-four percent of patients in the early administration group achieved successful stem cell mobilization compared with 81.6% in the standard administration group (P = .0111). The median number of plerixafor days to reach the collection goal of  ≥2 × 10 6 CD34 + cells/kg was 1 day for

  6. Interleukin-6 Regulates Adult Neural Stem Cell Numbers during Normal and Abnormal Post-natal Development

    Directory of Open Access Journals (Sweden)

    Mekayla A. Storer

    2018-05-01

    Full Text Available Summary: Circulating systemic factors can regulate adult neural stem cell (NSC biology, but the identity of these circulating cues is still being defined. Here, we have focused on the cytokine interleukin-6 (IL-6, since increased circulating levels of IL-6 are associated with neural pathologies such as autism and bipolar disorder. We show that IL-6 promotes proliferation of post-natal murine forebrain NSCs and that, when the IL-6 receptor is inducibly knocked out in post-natal or adult neural precursors, this causes a long-term decrease in forebrain NSCs. Moreover, a transient circulating surge of IL-6 in perinatal or adult mice causes an acute increase in neural precursor proliferation followed by long-term depletion of adult NSC pools. Thus, IL-6 signaling is both necessary and sufficient for adult NSC self-renewal, and acute perturbations in circulating IL-6, as observed in many pathological situations, have long-lasting effects on the size of adult NSC pools. : In this report, Storer and colleagues demonstrate that the circulating cytokine IL-6, which is elevated in humans in different pathological situations, can perturb neural stem cell biology after birth. They show that IL-6 signaling is essential for self-renewal and maintenance of post-natal and adult NSCs in the murine forebrain under normal homeostatic conditions. Keywords: interleukin-6, neural stem cell, adult neurogenesis, CNS cytokines, postnatal brain development, stem cell depletion, neural stem cell niche, circulating stem cell factors, olfactory bulb

  7. Expression of the chicken GDNF family receptor alpha-1 as a marker of spermatogonial stem cells

    Czech Academy of Sciences Publication Activity Database

    Mucksová, J.; Kalina, J.; Bakst, M.; Yan, H.; Brillard, J.-P.; Benešová, B.; Fafílek, Bohumil; Hejnar, Jiří; Trefil, P.

    2013-01-01

    Roč. 142, 1-2 (2013), s. 75-83 ISSN 0378-4320 R&D Projects: GA ČR GAP502/11/2207 Grant - others:GA MŠk(CZ) ME10104 Institutional support: RVO:68378050 Keywords : GFRα1 * chicken spermatogonial stem cell * male germ line transplantation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.581, year: 2013

  8. Differentiated cells are more efficient than adult stem cells for cloning by somatic cell nuclear transfer.

    Science.gov (United States)

    Sung, Li-Ying; Gao, Shaorong; Shen, Hongmei; Yu, Hui; Song, Yifang; Smith, Sadie L; Chang, Ching-Chien; Inoue, Kimiko; Kuo, Lynn; Lian, Jin; Li, Ao; Tian, X Cindy; Tuck, David P; Weissman, Sherman M; Yang, Xiangzhong; Cheng, Tao

    2006-11-01

    Since the creation of Dolly via somatic cell nuclear transfer (SCNT), more than a dozen species of mammals have been cloned using this technology. One hypothesis for the limited success of cloning via SCNT (1%-5%) is that the clones are likely to be derived from adult stem cells. Support for this hypothesis comes from the findings that the reproductive cloning efficiency for embryonic stem cells is five to ten times higher than that for somatic cells as donors and that cloned pups cannot be produced directly from cloned embryos derived from differentiated B and T cells or neuronal cells. The question remains as to whether SCNT-derived animal clones can be derived from truly differentiated somatic cells. We tested this hypothesis with mouse hematopoietic cells at different differentiation stages: hematopoietic stem cells, progenitor cells and granulocytes. We found that cloning efficiency increases over the differentiation hierarchy, and terminally differentiated postmitotic granulocytes yield cloned pups with the greatest cloning efficiency.

  9. The helix-loop-helix protein id1 controls stem cell proliferation during regenerative neurogenesis in the adult zebrafish telencephalon.

    Science.gov (United States)

    Rodriguez Viales, Rebecca; Diotel, Nicolas; Ferg, Marco; Armant, Olivier; Eich, Julia; Alunni, Alessandro; März, Martin; Bally-Cuif, Laure; Rastegar, Sepand; Strähle, Uwe

    2015-03-01

    The teleost brain has the remarkable ability to generate new neurons and to repair injuries during adult life stages. Maintaining life-long neurogenesis requires careful management of neural stem cell pools. In a genome-wide expression screen for transcription regulators, the id1 gene, encoding a negative regulator of E-proteins, was found to be upregulated in response to injury. id1 expression was mapped to quiescent type I neural stem cells in the adult telencephalic stem cell niche. Gain and loss of id1 function in vivo demonstrated that Id1 promotes stem cell quiescence. The increased id1 expression observed in neural stem cells in response to injury appeared independent of inflammatory signals, suggesting multiple antagonistic pathways in the regulation of reactive neurogenesis. Together, we propose that Id1 acts to maintain the neural stem cell pool by counteracting neurogenesis-promoting signals. © 2014 AlphaMed Press.

  10. Medicina regenerativa: Células madre embrionarias y adultas Regenerative medicine: Embryonic and adult stem cells

    Directory of Open Access Journals (Sweden)

    Porfirio Hernández Ramírez

    2004-12-01

    Full Text Available En los últimos años ha surgido una nueva rama de la medicina denominada medicina regenerativa, basada fundamentalmente en los nuevos conocimientos sobre las células madre y en su capacidad de convertirse en células de diferentes tejidos. Las células madre se clasifican en embrionarias y somáticas o adultas. Durante varios años se consideró que la célula madre hematopoyética era la única célula en la médula ósea con capacidad generativa. Sin embargo, estudios recientes han mostrado que la composición de la médula ósea es más compleja, pues en ella se ha identificado un grupo heterogéneo de células madre adultas, entre las que se encuentran las: hematopoyéticas, mesenquimales (estromales, población lateral, células progenitoras adultas multipotentes (MAPC. Varios estudios han sugerido que la potencialidad de algunos tipos de células madre adultas es mayor de lo esperado, pues han mostrado en determinadas condiciones capacidad para diferenciarse en células de diferentes linajes, lo que las acercan a la potencialidad de las células embrionarias. Esto ha creado nuevas perspectivas para el tratamiento de diferentes enfermedades con células madre adultas, lo que inicialmente se pensaba solo podía hacerse con las embrionariasIn the last few years, there has emerged a new branch of medicine called regenerative medicine based mainly on the new knowledge about stem cells and their capacity to turn into cells of different tissues. Stem cells are classified into embryonic cells and somatic or adult cells. For many years, it was believed that hematopoietic stem cell was the only one with regenerative capacity in the bone-marrow. However, recent studies have shown that the composition of the bone marrow is more complex an heterogeneous group of adult stem cells such as hematopoietic, mesenchymal (stromal, lateral population and multipotent adult progenitor cells have been identified there. Several studies suggested that the

  11. Spontaneous transformation of adult mesenchymal stem cells from cynomolgus macaques in vitro

    International Nuclear Information System (INIS)

    Ren, Zhenhua; Wang, Jiayin; Zhu, Wanwan; Guan, Yunqian; Zou, Chunlin; Chen, Zhiguo; Zhang, Y. Alex

    2011-01-01

    Mesenchymal stem cells (MSCs) have shown potential clinical utility in cell therapy and tissue engineering, due to their ability to proliferate as well as to differentiate into multiple lineages, including osteogenic, adipogenic, and chondrogenic specifications. Therefore, it is crucial to assess the safety of MSCs while extensive expansion ex vivo is a prerequisite to obtain the cell numbers for cell transplantation. Here we show that MSCs derived from adult cynomolgus monkey can undergo spontaneous transformation following in vitro culture. In comparison with MSCs, the spontaneously transformed mesenchymal cells (TMCs) display significantly different growth pattern and morphology, reminiscent of the characteristics of tumor cells. Importantly, TMCs are highly tumorigenic, causing subcutaneous tumors when injected into NOD/SCID mice. Moreover, no multiple differentiation potential of TMCs is observed in vitro or in vivo, suggesting that spontaneously transformed adult stem cells may not necessarily turn into cancer stem cells. These data indicate a direct transformation of cynomolgus monkey MSCs into tumor cells following long-term expansion in vitro. The spontaneous transformation of the cultured cynomolgus monkey MSCs may have important implications for ongoing clinical trials and for models of oncogenesis, thus warranting a more strict assessment of MSCs prior to cell therapy. -- Highlights: ► Spontaneous transformation of cynomolgus monkey MSCs in vitro. ► Transformed mesenchymal cells lack multipotency. ► Transformed mesenchymal cells are highly tumorigenic. ► Transformed mesenchymal cells do not have the characteristics of cancer stem cells.

  12. Being a haematopoietic stem cell donor for a sick sibling: Adult donors' experiences prior to donation.

    Science.gov (United States)

    Kisch, Annika; Bolmsjö, Ingrid; Lenhoff, Stig; Bengtsson, Mariette

    2015-10-01

    There is a lack of knowledge about sibling stem cell donors' experiences pre-donation and the waiting period before the donation might have been long. The donors and their corresponding sibling recipients were simultaneously included in two different interview studies. The results from the recipient study have been presented in a separate paper. The aim was to explore the experiences of being a stem cell donor for a sibling, prior to donation. Ten adult sibling donors were interviewed prior to stem cell donation. The interviews were digitally recorded, transcribed verbatim and subjected to qualitative content analysis. The main theme Being a cog in a big wheel describes the complex process of being a sibling donor prior to donation, covering a mixture of emotions and thoughts. The four subthemes Being available, Being anxious, Being concerned and Being obliged cover the various experiences. The sibling donors' experiences are influenced by the quality of the relationship with the sick sibling. Sibling stem cell donors go through a complex process once they have accidentally got involved in. They have been asked to become a donor; it was not a voluntary choice. In caring for sibling stem cell donors the nurses should be aware of the complexity of the process they experience and take into consideration their personal situation and needs. Providing optimal care for both sibling donors and their corresponding recipients is a challenge, and further improvement and exploration are needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Loss of DNA mismatch repair imparts a selective advantage in planarian adult stem cells.

    Directory of Open Access Journals (Sweden)

    Jessica P Hollenbach

    Full Text Available Lynch syndrome (LS leads to an increased risk of early-onset colorectal and other types of cancer and is caused by germline mutations in DNA mismatch repair (MMR genes. Loss of MMR function results in a mutator phenotype that likely underlies its role in tumorigenesis. However, loss of MMR also results in the elimination of a DNA damage-induced checkpoint/apoptosis activation barrier that may allow damaged cells to grow unchecked. A fundamental question is whether loss of MMR provides pre-cancerous stem cells an immediate selective advantage in addition to establishing a mutator phenotype. To test this hypothesis in an in vivo system, we utilized the planarian Schmidtea mediterranea which contains a significant population of identifiable adult stem cells. We identified a planarian homolog of human MSH2, a MMR gene which is mutated in 38% of LS cases. The planarian Smed-msh2 is expressed in stem cells and some progeny. We depleted Smed-msh2 mRNA levels by RNA-interference and found a striking survival advantage in these animals treated with a cytotoxic DNA alkylating agent compared to control animals. We demonstrated that this tolerance to DNA damage is due to the survival of mitotically active, MMR-deficient stem cells. Our results suggest that loss of MMR provides an in vivo survival advantage to the stem cell population in the presence of DNA damage that may have implications for tumorigenesis.

  14. Induced adult stem (iAS) cells and induced transit amplifying progenitor (iTAP) cells-a possible alternative to induced pluripotent stem (iPS) cells?

    Science.gov (United States)

    Heng, Boon Chin; Richards, Mark; Ge, Zigang; Shu, Yimin

    2010-02-01

    The successful derivation of iPSC lines effectively demonstrates that it is possible to reset the 'developmental clock' of somatic cells all the way back to the initial embryonic state. Hence, it is plausible that this clock may instead be turned back half-way to a less immature developmental stage that is more directly applicable to clinical therapeutic applications or for in vitro pharmacology/toxicology screening assays. Such a suitable developmental state is postulated to be either the putative transit amplifying progenitor stage or adult stem cell stage. It is hypothetically possible to reprogram mature and terminally differentiated somatic cells back to the adult stem cell or transit amplifying progenitor stage, in a manner similar to the derivation of iPSC. It is proposed that the terminology 'Induced Adult Stem Cells' (iASC) or 'Induced Transit Amplifying Progenitor Cells' (iTAPC) be used to described such reprogrammed somatic cells. Of particular interest, is the possibility of resetting the developmental clock of mature differentiated somatic cells of the mesenchymal lineage, explanted from adipose tissue, bone marrow and cartilage. The putative adult stem cell sub-population from which these cells are derived, commonly referred to as 'mesenchymal stem cells', are highly versatile and hold much therapeutic promise in regenerative medicine, as attested to by numerous human clinical trials and animal studies. Perhaps it may be appropriate to term such reprogrammed cells as 'Induced Mesenchymal Stem Cells' (iMSC) or as 'Induced Mesenchumal Progenitor Cells' (iMPC). Given that cells from the same organ/tissue will share some commonalities in gene expression, we hypothesize that the generation of iASC or iTAPC would be more efficient as compared to iPSC generation, since a common epigenetic program must exist between the reprogrammed cells, adult stem cell or progenitor cell types and terminally differentiated cell types from the same organ/tissue.

  15. Regulatory System for Stem/Progenitor Cell Niches in the Adult Rodent Pituitary

    Science.gov (United States)

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    The anterior lobe of the pituitary gland is a master endocrine tissue composed of five types of endocrine cells. Although the turnover rate of pituitary endocrine cells is as low as about 1.6% per day, recent studies have demonstrated that Sex-determining region Y-box 2 (SOX2)+-cells exist as pituitary stem/progenitor cells in the adult anterior lobe and contribute to cell regeneration. Notably, SOX2+-pituitary stem/progenitor cells form two types of niches in this tissue: the marginal cell layer (MCL-niche) and the dense cell clusters scattering in the parenchyma (parenchymal-niche). However, little is known about the mechanisms and factors for regulating the pituitary stem/progenitor cell niches, as well as the functional differences between the two types of niches. Elucidation of the regulatory mechanisms in the niches might enable us to understand the cell regeneration system that acts in accordance with physiological demands in the adult pituitary. In this review, so as to reveal the regulatory mechanisms of the two types of niche, we summarize the regulatory factors and their roles in the adult rodent pituitary niches by focusing on three components: soluble factors, cell surface proteins and extracellular matrixes. PMID:26761002

  16. Regulatory System for Stem/Progenitor Cell Niches in the Adult Rodent Pituitary

    Directory of Open Access Journals (Sweden)

    Saishu Yoshida

    2016-01-01

    Full Text Available The anterior lobe of the pituitary gland is a master endocrine tissue composed of five types of endocrine cells. Although the turnover rate of pituitary endocrine cells is as low as about 1.6% per day, recent studies have demonstrated that Sex-determining region Y-box 2 (SOX2+-cells exist as pituitary stem/progenitor cells in the adult anterior lobe and contribute to cell regeneration. Notably, SOX2+-pituitary stem/progenitor cells form two types of niches in this tissue: the marginal cell layer (MCL-niche and the dense cell clusters scattering in the parenchyma (parenchymal-niche. However, little is known about the mechanisms and factors for regulating the pituitary stem/progenitor cell niches, as well as the functional differences between the two types of niches. Elucidation of the regulatory mechanisms in the niches might enable us to understand the cell regeneration system that acts in accordance with physiological demands in the adult pituitary. In this review, so as to reveal the regulatory mechanisms of the two types of niche, we summarize the regulatory factors and their roles in the adult rodent pituitary niches by focusing on three components: soluble factors, cell surface proteins and extracellular matrixes.

  17. Postnatal stem/progenitor cells derived from the dental pulp of adult chimpanzee

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    Fillos Dimitri

    2008-04-01

    Full Text Available Background Chimpanzee dental pulp stem/stromal cells (ChDPSCs are very similar to human bone marrow derived mesenchymal stem/stromal cells (hBMSCs as demonstrated by the expression pattern of cell surface markers and their multipotent differentiation capability. Results ChDPSCs were isolated from an incisor and a canine of a forty-seven year old female chimpanzee. A homogenous population of ChDPSCs was established in early culture at a high proliferation rate and verified by the expression pattern of thirteen cell surface markers. The ChDPSCs are multipotent and were capable of differentiating into osteogenic, adipogenic and chondrogenic lineages under appropriate in vitro culture conditions. ChDPSCs also express stem cell (Sox-2, Nanog, Rex-1, Oct-4 and osteogenic (Osteonectin, osteocalcin, osteopontin markers, which is comparable to reported results of rhesus monkey BMSCs (rBMSCs, hBMSCs and hDPSCs. Although ChDPSCs vigorously proliferated during the initial phase and gradually decreased in subsequent passages, the telomere length indicated that telomerase activity was not significantly reduced. Conclusion These results demonstrate that ChDPSCs can be efficiently isolated from post-mortem teeth of adult chimpanzees and are multipotent. Due to the almost identical genome composition of humans and chimpanzees, there is an emergent need for defining the new role of chimpanzee modeling in comparative medicine. Teeth are easy to recover at necropsy and easy to preserve prior to the retrieval of dental pulp for stem/stromal cells isolation. Therefore, the establishment of ChDPSCs would preserve and maximize the applications of such a unique and invaluable animal model, and could advance the understanding of cellular functions and differentiation control of adult stem cells in higher primates.

  18. Postnatal stem/progenitor cells derived from the dental pulp of adult chimpanzee.

    Science.gov (United States)

    Cheng, Pei-Hsun; Snyder, Brooke; Fillos, Dimitri; Ibegbu, Chris C; Huang, Anderson Hsien-Cheng; Chan, Anthony W S

    2008-04-22

    Chimpanzee dental pulp stem/stromal cells (ChDPSCs) are very similar to human bone marrow derived mesenchymal stem/stromal cells (hBMSCs) as demonstrated by the expression pattern of cell surface markers and their multipotent differentiation capability. ChDPSCs were isolated from an incisor and a canine of a forty-seven year old female chimpanzee. A homogenous population of ChDPSCs was established in early culture at a high proliferation rate and verified by the expression pattern of thirteen cell surface markers. The ChDPSCs are multipotent and were capable of differentiating into osteogenic, adipogenic and chondrogenic lineages under appropriate in vitro culture conditions. ChDPSCs also express stem cell (Sox-2, Nanog, Rex-1, Oct-4) and osteogenic (Osteonectin, osteocalcin, osteopontin) markers, which is comparable to reported results of rhesus monkey BMSCs (rBMSCs), hBMSCs and hDPSCs. Although ChDPSCs vigorously proliferated during the initial phase and gradually decreased in subsequent passages, the telomere length indicated that telomerase activity was not significantly reduced. These results demonstrate that ChDPSCs can be efficiently isolated from post-mortem teeth of adult chimpanzees and are multipotent. Due to the almost identical genome composition of humans and chimpanzees, there is an emergent need for defining the new role of chimpanzee modeling in comparative medicine. Teeth are easy to recover at necropsy and easy to preserve prior to the retrieval of dental pulp for stem/stromal cells isolation. Therefore, the establishment of ChDPSCs would preserve and maximize the applications of such a unique and invaluable animal model, and could advance the understanding of cellular functions and differentiation control of adult stem cells in higher primates.

  19. Leptin-dependent neurotoxicity via induction of apoptosis in adult rat neural stem cells

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    Stéphanie eSEGURA

    2015-09-01

    Full Text Available Adipocyte-derived hormone leptin has been recently implicated in the control of neuronal plasticity. To explore whether modulation of adult neurogenesis may contribute to leptin control of neuronal plasticity, we used the neurosphere assay of neural stem cells derived from the adult rat subventricular zone (SVZ. Endogenous expression of specific leptin receptor (ObRb transcripts, as revealed by RT-PCR, is associated with activation of both ERK and STAT-3 pathways via phosphorylation of the critical ERK/STAT-3 amino acid residues upon addition of leptin to neurospheres. Furthermore, leptin triggered withdrawal of neural stem cells from the cell cycle as monitored by Ki67 labelling. This effect was blocked by pharmacological inhibition of ERK activation thus demonstrating that ERK mediates leptin effects on neural stem cell expansion. Leptin-dependent withdrawal of neural stem cells from the cell cycle was associated with increased apoptosis, as detected by TUNEL, which was preceded by cyclin D1 induction. Cyclin D1 was indeed extensively colocalized with TUNEL-positive apoptotic cells. Cyclin-D1 silencing by specific shRNA prevented leptin-induced decrease of the cell number per neurosphere thus pointing to the causal relationship between leptin actions on apoptosis and cyclin D1 induction. Leptin target cells in SVZ neurospheres were identified by double TUNEL/phenotypic marker immunocytofluorescence as differentiating neurons mostly. The inhibition of neural stem cell expansion via ERK/cyclin D1-triggered apoptosis defines novel biological action of leptin which may be involved in adiposity-dependent neurotoxicity.

  20. In Vitro and In Vivo Hepatic Differentiation of Adult Somatic Stem Cells and Extraembryonic Stem Cells for Treating End Stage Liver Diseases

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    Chenxia Hu

    2015-01-01

    Full Text Available The shortage of liver donors is a major handicap that prevents most patients from receiving liver transplantation and places them on a waiting list for donated liver tissue. Then, primary hepatocyte transplantation and bioartificial livers have emerged as two alternative treatments for these often fatal diseases. However, another problem has emerged. Functional hepatocytes for liver regeneration are in short supply, and they will dedifferentiate immediately in vitro after they are isolated from liver tissue. Alternative stem-cell-based therapeutic strategies, including hepatic stem cells (HSCs, embryonic stem cells (ESCs, induced pluripotent stem cells (iPSCs, and mesenchymal stem cells (MSCs, are more promising, and more attention has been devoted to these approaches because of the high potency and proliferation ability of the cells. This review will focus on the general characteristics and the progress in hepatic differentiation of adult somatic stem cells and extraembryonic stem cells in vitro and in vivo for the treatment of end stage liver diseases. The hepatic differentiation of stem cells would offer an ideal and promising source for cell therapy and tissue engineering for treating liver diseases.

  1. Germline stem cells and neo-oogenesis in the adult human ovary.

    Science.gov (United States)

    Liu, Yifei; Wu, Chao; Lyu, Qifeng; Yang, Dongzi; Albertini, David F; Keefe, David L; Liu, Lin

    2007-06-01

    It remains unclear whether neo-oogenesis occurs in postnatal ovaries of mammals, based on studies in mice. We thought to test whether adult human ovaries contain germline stem cells (GSCs) and undergo neo-oogenesis. Rather than using genetic manipulation which is unethical in humans, we took the approach of analyzing the expression of meiotic marker genes and genes for germ cell proliferation, which are required for neo-oogenesis, in adult human ovaries covering an age range from 28 to 53 years old, compared to testis and fetal ovaries served as positive controls. We show that active meiosis, neo-oogenesis and GSCs are unlikely to exist in normal, adult, human ovaries. No early meiotic-specific or oogenesis-associated mRNAs for SPO11, PRDM9, SCP1, TERT and NOBOX were detectable in adult human ovaries using RT-PCR, compared to fetal ovary and adult testis controls. These findings are further corroborated by the absence of early meiocytes and proliferating germ cells in adult human ovarian cortex probed with markers for meiosis (SCP3), oogonium (OCT3/4, c-KIT), and cell cycle progression (Ki-67, PCNA), in contrast to fetal ovary controls. If postnatal oogenesis is confirmed in mice, then this species would represent an exception to the rule that neo-oogenesis does not occur in adults.

  2. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland.

    Science.gov (United States)

    Pyczek, Joanna; Buslei, Rolf; Schult, David; Hölsken, Annett; Buchfelder, Michael; Heß, Ina; Hahn, Heidi; Uhmann, Anja

    2016-04-25

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and Sox9(+) adult pituitary stem cells and to elevated expression levels of adrenocorticotropic hormone (Acth), growth hormone (Gh) and prolactin (Prl) in the adult gland. Inhibition of the pathway by cyclopamine reversed these effects indicating that active Hh signaling positively regulates proliferative processes of adult pituitary stem cells and hormone production in the anterior pituitary. Since hormone producing cells of the adenohypophysis as well as ACTH-, GH- and PRL-immunopositive adenomas express SHH and its target GLI1, we furthermore propose that excess HH signaling is involved in the development/maintenance of hormone-producing pituitary adenomas. These findings advance the understanding of physiological hormone regulation and may open new treatment options for pituitary tumors.

  3. Novel Action of FSH on Stem Cells in Adult Mammalian Ovary Induces Postnatal Oogenesis and Primordial Follicle Assembly

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    Deepa Bhartiya

    2016-01-01

    Full Text Available Adult mammalian ovary has been under the scanner for more than a decade now since it was proposed to harbor stem cells that undergo postnatal oogenesis during reproductive period like spermatogenesis in testis. Stem cells are located in the ovary surface epithelium and exist in adult and menopausal ovary as well as in ovary with premature failure. Stem cells comprise two distinct populations including spherical, very small embryonic-like stem cells (VSELs which express nuclear OCT-4 and other pluripotent and primordial germ cells specific markers and slightly bigger ovarian germ stem cells (OGSCs with cytoplasmic OCT-4 which are equivalent to spermatogonial stem cells in the testes. These stem cells have the ability to spontaneously differentiate into oocyte-like structures in vitro and on exposure to a younger healthy niche. Bone marrow may be an alternative source of these stem cells. The stem cells express FSHR and respond to FSH by undergoing self-renewal, clonal expansion, and initiating neo-oogenesis and primordial follicle assembly. VSELs are relatively quiescent and were recently reported to survive chemotherapy and initiate oogenesis in mice when exposed to FSH. This emerging understanding and further research in the field will help evolving novel strategies to manage ovarian pathologies and also towards oncofertility.

  4. Use of Adult Stem Cells for Cartilage Tissue Engineering: Current Status and Future Developments

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    Catherine Baugé

    2015-01-01

    Full Text Available Due to their low self-repair ability, cartilage defects that result from joint injury, aging, or osteoarthritis, are the most often irreversible and are a major cause of joint pain and chronic disability. So, in recent years, researchers and surgeons have been working hard to elaborate cartilage repair interventions for patients who suffer from cartilage damage. However, current methods do not perfectly restore hyaline cartilage and may lead to the apparition of fibro- or hypertrophic cartilage. In the next years, the development of new strategies using adult stem cells, in scaffolds, with supplementation of culture medium and/or culture in low oxygen tension should improve the quality of neoformed cartilage. Through these solutions, some of the latest technologies start to bring very promising results in repairing cartilage from traumatic injury or chondropathies. This review discusses the current knowledge about the use of adult stem cells in the context of cartilage tissue engineering and presents clinical trials in progress, as well as in the future, especially in the field of bioprinting stem cells.

  5. Regenerative medicine using adult neural stem cells: the potential for diabetes therapy and other pharmaceutical applications

    Institute of Scientific and Technical Information of China (English)

    Tomoko Kuwabara; Makoto Asashima

    2012-01-01

    Neural stem cells (NSCs),which are responsible for continuous neurogenesis during the adult stage,are present in human adults.The typical neurogenic regions are the hippocampus and the subventricular zone; recent studies have revealed that NSCs also exist in the olfactory bulb.Olfactory bulb-derived neural stem cells (OB NSCs) have the potential to be used in therapeutic applications and can be easily harvested without harm to the patient.Through the combined influence of extrinsic cues and innate programming,adult neurogenesis is a finely regulated process occurring in a specialized cellular environment,a niche.Understanding the regulatory mechanisms of adult NSCs and their cellular niche is not only important to understand the physiological roles of neurogenesis in adulthood,but also to provide the knowledge necessary for developing new therapeutic applications using adult NSCs in other organs with similar regulatory environments.Diabetes is a devastating disease affecting more than 200 million people worldwide.Numerous diabetic patients suffer increased symptom severity after the onset,involving complications such as retinopathy and nephropathy.Therefore,the development of treatments for fundamental diabetes is important.The utilization of autologous cells from patients with diabetes may address challenges regarding the compatibility of donor tissues as well as provide the means to naturally and safely restore function,reducing future risks while also providing a long-term cure.Here,we review recent findings regarding the use of adult OB NSCs as a potential diabetes cure,and discuss the potential of OB NSC-based pharmaceutical applications for neuronal diseases and mental disorders.

  6. New insights into mechanisms of stem cell daughter fate determination in regenerative tissues.

    Science.gov (United States)

    Sada, Aiko; Tumbar, Tudorita

    2013-01-01

    Stem cells can self-renew and differentiate over extended periods of time. Understanding how stem cells acquire their fates is a central question in stem cell biology. Early work in Drosophila germ line and neuroblast showed that fate choice is achieved by strict asymmetric divisions that can generate each time one stem and one differentiated cell. More recent work suggests that during homeostasis, some stem cells can divide symmetrically to generate two differentiated cells or two identical stem cells to compensate for stem cell loss that occurred by direct differentiation or apoptosis. The interplay of all these factors ensures constant tissue regeneration and the maintenance of stem cell pool size. This interplay can be modeled as a population-deterministic dynamics that, at least in some systems, may be described as stochastic behavior. Here, we overview recent progress made on the characterization of stem cell dynamics in regenerative tissues. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Leucine-rich repeat-containing G-protein-coupled receptors as markers of adult stem cells

    NARCIS (Netherlands)

    Barker, N.; Clevers, H.

    2010-01-01

    Molecular markers are used to characterize and track adult stem cells. Colon cancer research has led to the identification of 2 related receptors, leucine-rich repeat-containing, G-protein-coupled receptors (Lgr)5 and Lgr6, that are expressed by small populations of cells in a variety of adult

  8. Distinct Molecular Signature of Murine Fetal Liver and Adult Hematopoietic Stem Cells Identify Novel Regulators of Hematopoietic Stem Cell Function.

    Science.gov (United States)

    Manesia, Javed K; Franch, Monica; Tabas-Madrid, Daniel; Nogales-Cadenas, Ruben; Vanwelden, Thomas; Van Den Bosch, Elisa; Xu, Zhuofei; Pascual-Montano, Alberto; Khurana, Satish; Verfaillie, Catherine M

    2017-04-15

    During ontogeny, fetal liver (FL) acts as a major site for hematopoietic stem cell (HSC) maturation and expansion, whereas HSCs in the adult bone marrow (ABM) are largely quiescent. HSCs in the FL possess faster repopulation capacity as compared with ABM HSCs. However, the molecular mechanism regulating the greater self-renewal potential of FL HSCs has not yet extensively been assessed. Recently, we published RNA sequencing-based gene expression analysis on FL HSCs from 14.5-day mouse embryo (E14.5) in comparison to the ABM HSCs. We reanalyzed these data to identify key transcriptional regulators that play important roles in the expansion of HSCs during development. The comparison of FL E14.5 with ABM HSCs identified more than 1,400 differentially expressed genes. More than 200 genes were shortlisted based on the gene ontology (GO) annotation term "transcription." By morpholino-based knockdown studies in zebrafish, we assessed the function of 18 of these regulators, previously not associated with HSC proliferation. Our studies identified a previously unknown role for tdg, uhrf1, uchl5, and ncoa1 in the emergence of definitive hematopoiesis in zebrafish. In conclusion, we demonstrate that identification of genes involved in transcriptional regulation differentially expressed between expanding FL HSCs and quiescent ABM HSCs, uncovers novel regulators of HSC function.

  9. Fragile x mental retardation protein regulates proliferation and differentiation of adult neural stem/progenitor cells.

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    Yuping Luo

    2010-04-01

    Full Text Available Fragile X syndrome (FXS, the most common form of inherited mental retardation, is caused by the loss of functional fragile X mental retardation protein (FMRP. FMRP is an RNA-binding protein that can regulate the translation of specific mRNAs. Adult neurogenesis, a process considered important for neuroplasticity and memory, is regulated at multiple molecular levels. In this study, we investigated whether Fmrp deficiency affects adult neurogenesis. We show that in a mouse model of fragile X syndrome, adult neurogenesis is indeed altered. The loss of Fmrp increases the proliferation and alters the fate specification of adult neural progenitor/stem cells (aNPCs. We demonstrate that Fmrp regulates the protein expression of several components critical for aNPC function, including CDK4 and GSK3beta. Dysregulation of GSK3beta led to reduced Wnt signaling pathway activity, which altered the expression of neurogenin1 and the fate specification of aNPCs. These data unveil a novel regulatory role for Fmrp and translational regulation in adult neurogenesis.

  10. Epigenetic regulation of neural stem cell property from embryo to adult

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    Naoya Murao

    2016-03-01

    Full Text Available Neural stem cells (NSCs have the ability to self-renew and give rise to neurons and glial cells (astrocytes and oligodendrocytes in the mammalian central nervous system. This multipotency is acquired by NSCs during development and is maintained throughout life. Proliferation, fate specification, and maturation of NSCs are regulated by both cell intrinsic and extrinsic factors. Epigenetic modification is a representative intrinsic factor, being involved in many biological aspects of central nervous system development and adult neurogenesis through the regulation of NSC dynamics. In this review, we summarize recent progress in the epigenetic regulation of NSC behavior in the embryonic and adult brain, with particular reference to DNA methylation, histone modification, and noncoding RNAs.

  11. Genomic Selection for Quantitative Adult Plant Stem Rust Resistance in Wheat

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    Jessica E. Rutkoski

    2014-11-01

    Full Text Available Quantitative adult plant resistance (APR to stem rust ( f. sp. is an important breeding target in wheat ( L. and a potential target for genomic selection (GS. To evaluate the relative importance of known APR loci in applying GS, we characterized a set of CIMMYT germplasm at important APR loci and on a genome-wide profile using genotyping-by-sequencing (GBS. Using this germplasm, we describe the genetic architecture and evaluate prediction models for APR using data from the international Ug99 stem rust screening nurseries. Prediction models incorporating markers linked to important APR loci and seedling phenotype scores as fixed effects were evaluated along with the classic prediction models: Multiple linear regression (MLR, Genomic best linear unbiased prediction (G-BLUP, Bayesian Lasso (BL, and Bayes Cπ (BCπ. We found the region to play an important role in APR in this germplasm. A model using linked markers as fixed effects in G-BLUP was more accurate than MLR with linked markers (-value = 0.12, and ordinary G-BLUP (-value = 0.15. Incorporating seedling phenotype information as fixed effects in G-BLUP did not consistently increase accuracy. Overall, levels of prediction accuracy found in this study indicate that GS can be effectively applied to improve stem rust APR in this germplasm, and if genotypes at linked markers are available, modeling these genotypes as fixed effects could lead to better predictions.

  12. Xenobiotic effects on intestinal stem cell proliferation in adult honey bee (Apis mellifera L) workers.

    Science.gov (United States)

    Forkpah, Cordelia; Dixon, Luke R; Fahrbach, Susan E; Rueppell, Olav

    2014-01-01

    The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species.

  13. Auto-mobilized adult hematopoietic stem cells advance neovasculature in diabetic retinopathy of mice

    Institute of Scientific and Technical Information of China (English)

    TIAN Bei; LI Xiao-xin; SHEN Li; ZHAO Min; YU Wen-zhen

    2010-01-01

    Background Hematopoietic stem cells (HSCs) can be used to deliver functionally active angiostatic molecules to the retinal vasculature by targeting active astrocytes and may be useful in targeting pre-angiogenic retinal lesions. We sought to determine whether HSC mobilization can ameliorate early diabetic retinopathy in mice.Methods Mice were devided into four groups: normal mice control group, normal mice HSC-mobilized group, diabetic mice control group and diabetic mice HSC mobilized group. Murine stem cell growth factor (murine SCF) and recombined human granulocyte colony stimulating factor (rhG-csf) were administered to the mice with diabetes and without diabetes for continuous 5 days to induce autologous HSCs mobilization, and subcutaneous injection of physiological saline was used as control. Immunohistochemical double staining was conducted with anti-mouse rat CD31 monoclonal antibody and anti-BrdU rat antibody.Results Marked HSCs clearly increased after SCF plus G-csf-mobilization. Non-mobilized diabetic mice showed more HSCs than normal mice (P=0.032), and peripheral blood significantly increased in both diabetic and normal mice (P=0.000).Diabetic mice showed more CD31 positive capillary vessels (P=0.000) and accelerated endothelial cell regeneration. Only diabetic HSC-mobilized mice expressed both BrdU and CD31 antigens in the endothelial cells of new capillaries.Conclusion Auto-mobilized adult hematopoietic stem cells advance neovasculature in diabetic retinopathy of mice.

  14. Regenerating medicine related to the stem-cells and its mechanisms of action from adults cells

    International Nuclear Information System (INIS)

    Hernandez Ramirez, Porfirio

    2009-01-01

    Regenerating medicine is a branch of Medicine very developed in past years. Advances in this field have been closely linked with the new knowledge achieved on stem-cells and its ability to become in cells of different tissues. This type of medicine is based on the behaviors adopted by organism to substitute those damaged cells by the healthy ones by different processes in specific tissues. Therapeutic measures used may include the stem-cell transplantation, the use of soluble molecules, genic therapy and tissues engineering. Nowadays, the more used method is the adult stem-cells. However, is not well known the mechanisms by which the transplanted cells could to improve or to promote the tissue regeneration. To explain these mechanisms some hypotheses has been proposed including the cellular trans-differentiation, cells fusion, and the effects secondaries to cells release by cells of different soluble molecules with specific actions; in addition to the autocrine and paracrine effects that may have these soluble factors, it is suggested too the existence of a telecrine action. It is probable that more than one of these mechanisms be executed

  15. Removing the cells from adult bone marrow derived stem cell therapy does not eliminate cardioprotection.

    Science.gov (United States)

    Yasin, Mohammed

    2013-04-01

    The debate as to whether adult stem cell therapy is regenerative or not continues. The non-regenerative benefits of adult bone marrow-derived stem cell therapy were investigated by testing whether the supernatant derived from unfractionated bone marrow mononuclear cells might be cardioprotective in an animal model of myocardial ischaemia-reperfusion injury. Regional myocardial reperfusion injury was acquired by 25 min reversible left anterior descending coronary artery (LAD) occlusion followed by 2 h reperfusion, in anaesthetized Wistar male rats. Unfractionated bone marrow mononuclear cells (BMMNC) isolated from sibling Wistar male rat whole bone marrow were phenotyped by fluorescence activated cell sorting flowcytometry for the haematopoietic stem cell surface markers c-kit, CD34, CD45 and CD133. Animals subjected to regional myocardial reperfusion injury received either 10 million BMMNC or BMMNC supernatant (BMS); both were collected in 0.5 ml phosphate-buffered saline and delivered by intravenous bolus at the onset of reperfusion. The left ventricular region distal to the LAD occlusion point was excised for measurement of myocardial infarct size and proteomic analysis, which was used to identify whether there were any differences in myocardial proteins associated with intravenous injection of either BMMNC or BMS. BMMNC were phenotyped to be c-kit(+) (7 ± 1%), CD34(+) (7 ± 1%), CD45(+) (54 ± 6%), CD133(+) (15 ± 1%). The supernatant reduced myocardial infarct size (BMS 34 ± 2%, n = 15 vs control 57 ± 2%, n = 7, P < 0.0001), which was comparable to the reduction in infarct size afforded by the injection of cells (BMMNC 33 ± 3% vs control 57 ± 2%, n = 10, P < 0.0001). Proteomics of hearts treated with either BMS or BMMNC demonstrated higher expression of (i) anti-apoptotic signal transduction protein: 14-3-3-epsilon (1.5-fold); (ii) anti-oxidants: peroxiredoxin-6 (2.1-fold); (iii) heat shock proteins: alpha B-crystallin (1.7-fold), heat shock protein 72 (2

  16. FSH-FSHR3-stem cells in ovary surface epithelium: basis for adult ovarian biology, failure, aging, and cancer.

    Science.gov (United States)

    Bhartiya, Deepa; Singh, Jarnail

    2015-01-01

    Despite extensive research, genetic basis of premature ovarian failure (POF) and ovarian cancer still remains elusive. It is indeed paradoxical that scientists searched for mutations in FSH receptor (FSHR) expressed on granulosa cells, whereas more than 90% of cancers arise in ovary surface epithelium (OSE). Two distinct populations of stem cells including very small embryonic-like stem cells (VSELs) and ovarian stem cells (OSCs) exist in OSE, are responsible for neo-oogenesis and primordial follicle assembly in adult life, and are modulated by FSH via its alternatively spliced receptor variant FSHR3 (growth factor type 1 receptor acting via calcium signaling and the ERK/MAPK pathway). Any defect in FSH-FSHR3-stem cell interaction in OSE may affect folliculogenesis and thus result in POF. Ovarian aging is associated with a compromised microenvironment that does not support stem cell differentiation into oocytes and further folliculogenesis. FSH exerts a mitogenic effect on OSE and elevated FSH levels associated with advanced age may provide a continuous trigger for stem cells to proliferate resulting in cancer, thus supporting gonadotropin theory for ovarian cancer. Present review is an attempt to put adult ovarian biology, POF, aging, and cancer in the perspective of FSH-FSHR3-stem cell network that functions in OSE. This hypothesis is further supported by the recent understanding that: i) cancer is a stem cell disease and OSE is the niche for ovarian cancer stem cells; ii) ovarian OCT4-positive stem cells are regulated by FSH; and iii) OCT4 along with LIN28 and BMP4 are highly expressed in ovarian cancers. © 2015 Society for Reproduction and Fertility.

  17. Can adult neural stem cells create new brains? Plasticity in the adult mammalian neurogenic niches: realities and expectations in the era of regenerative biology.

    Science.gov (United States)

    Kazanis, Ilias

    2012-02-01

    Since the first experimental reports showing the persistence of neurogenic activity in the adult mammalian brain, this field of neurosciences has expanded significantly. It is now widely accepted that neural stem and precursor cells survive during adulthood and are able to respond to various endogenous and exogenous cues by altering their proliferation and differentiation activity. Nevertheless, the pathway to therapeutic applications still seems to be long. This review attempts to summarize and revisit the available data regarding the plasticity potential of adult neural stem cells and of their normal microenvironment, the neurogenic niche. Recent data have demonstrated that adult neural stem cells retain a high level of pluripotency and that adult neurogenic systems can switch the balance between neurogenesis and gliogenesis and can generate a range of cell types with an efficiency that was not initially expected. Moreover, adult neural stem and precursor cells seem to be able to self-regulate their interaction with the microenvironment and even to contribute to its synthesis, altogether revealing a high level of plasticity potential. The next important step will be to elucidate the factors that limit this plasticity in vivo, and such a restrictive role for the microenvironment is discussed in more details.

  18. Activation of Sox3 Gene by Thyroid Hormone in the Developing Adult Intestinal Stem Cell During Xenopus Metamorphosis

    Science.gov (United States)

    Sun, Guihong; Fu, Liezhen; Wen, Luan

    2014-01-01

    The maturation of the intestine into the adult form involves the formation of adult stem cells in a thyroid hormone (T3)-dependent process in vertebrates. In mammals, this takes place during postembryonic development, a period around birth when the T3 level peaks. Due to the difficulty of manipulating late-stage, uterus-enclosed embryos, very little is known about the development of the adult intestinal stem cells. Interestingly, the remodeling of the intestine during the T3-dependent amphibian metamorphosis mimics the maturation of mammalian intestine. Our earlier microarray studies in Xenopus laevis revealed that the transcription factor SRY (sex-determining region Y)-box 3 (Sox3), well known for its involvement in neural development, was upregulated in the intestinal epithelium during metamorphosis. Here, we show that Sox3 is highly and specifically expressed in the developing adult intestinal progenitor/stem cells. We further show that its induction by T3 is independent of new protein synthesis, suggesting that Sox3 is directly activated by liganded T3 receptor. Thus, T3 activates Sox3 as one of the earliest changes in the epithelium, and Sox3 in turn may facilitate the dedifferentiation of the larval epithelial cells into adult stem cells. PMID:25211587

  19. Adult stem cell theory of the multi-stage, multi-mechanism theory of carcinogenesis: role of inflammation on the promotion of initiated stem cells.

    Science.gov (United States)

    Trosko, James E; Tai, Mei-Hui

    2006-01-01

    Inflammation, induced by microbial agents, radiation, endogenous or exogenous chemicals, has been associated with chronic diseases, including cancer. Since carcinogenesis has been characterized as consisting of the 'initiation', 'promotion' and 'progression' phases, the inflammatory process could affect any or all three phases. The stem cell theory of carcinogenesis has been given a revival, in that isolated human adult stem cells have been isolated and shown to be 'targets' for neoplastic transformation. Oct4, a transcription factor, has been associated with adult stem cells, as well as their immortalized and tumorigenic derivatives, but not with the normal differentiated daughters. These data are consistent with the stem cell theory of carcinogenesis. In addition, Gap Junctional Intercellular Communication (GJIC) seems to play a major role in cell growth. Inhibition of GJIC by non-genotoxic chemicals or various oncogenes seems to be the mechanism for the tumor promotion and progression phases of carcinogenesis. Many of the toxins, synthetic non-genotoxicants, and endogenous inflammatory factors have been shown to inhibit GJIC and act as tumor promoters. The inhibition of GJIC might be the mechanism by which the inflammatory process affects cancer and that to intervene during tumor promotion with anti-inflammatory factors might be the most efficacious anti-cancer strategy.

  20. Transgenerational epigenetic effects of the endocrine disruptor vinclozolin on pregnancies and female adult onset disease

    OpenAIRE

    Nilsson, Eric E; Anway, Matthew D; Stanfield, Jacob; Skinner, Michael K

    2008-01-01

    Endocrine disruptor exposure during gonadal sex determination was previously found to induce male rat adult onset transgenerational disease (F1–F4 generation), and this was associated with an alteration in the epigenetic (i.e., DNA methylation) programming of the male germ line. The current study was designed to characterize the transgenerational disease phenotypes of the female adult offspring. Pregnant rats (F0 generation) were treated transiently with vinclozolin (i.e., fungicide with anti...

  1. Brain Cancer Stem Cells in Adults and Children: Cell Biology and Therapeutic Implications.

    Science.gov (United States)

    Abou-Antoun, Tamara J; Hale, James S; Lathia, Justin D; Dombrowski, Stephen M

    2017-04-01

    Brain tumors represent some of the most malignant cancers in both children and adults. Current treatment options target the majority of tumor cells but do not adequately target self-renewing cancer stem cells (CSCs). CSCs have been reported to resist the most aggressive radiation and chemotherapies, and give rise to recurrent, treatment-resistant secondary malignancies. With advancing technologies, we now have a better understanding of the genetic, epigenetic and molecular signatures and microenvironmental influences which are useful in distinguishing between distinctly different tumor subtypes. As a result, efforts are now underway to identify and target CSCs within various tumor subtypes based on this foundation. This review discusses progress in CSC biology as it relates to targeted therapies which may be uniquely different between pediatric and adult brain tumors. Studies to date suggest that pediatric brain tumors may benefit more from genetic and epigenetic targeted therapies, while combination treatments aimed specifically at multiple molecular pathways may be more effective in treating adult brain tumors which seem to have a greater propensity towards microenvironmental interactions. Ultimately, CSC targeting approaches in combination with current clinical therapies have the potential to be more effective owing to their ability to compromise CSCs maintenance and the mechanisms which underlie their highly aggressive and deadly nature.

  2. Is there any reason to prefer cord blood instead of adult donors for hematopoietic stem cell transplants?

    Directory of Open Access Journals (Sweden)

    Meral eBeksac

    2016-01-01

    Full Text Available As cord blood (CB enables rapid access and tolerance to HLA mismatches, number of unrelated cord blood transplants have reached 30 000. Such transplant activity has been the result of international accreditation programs maintaining highly qualified CBUs reaching more than 600 000 CBUs stored worldwide. Efforts to increase stem cell content or engraftment rate of the graft by ex vivo expansion, modulation by molecules such as fucose, Prostaglandin E2 derivative, complement, CD26 inhibitors or CXCR4/CXCL12 axis have been able to accelerate engraftment speed and rate. Furthermore introduction of reduced intensity conditioning protocols, better HLA matching and recognition of the importance of HLA-C have improved CBT success by decreasing Transplant Related Mortality (TRM. Cord blood progenitor/stem cell content has been compared with adult stem cells revealing higher long-term repopulating capacity compared to BM-MSC and less oncogenic potential than Induced Progenitor Stem Cells. This chapter summarizes the advantage and disadvantages of CB compared to adult stem cells within the context of stem cell biology and transplantation.

  3. Is There Any Reason to Prefer Cord Blood Instead of Adult Donors for Hematopoietic Stem Cell Transplants?

    Science.gov (United States)

    Beksac, Meral

    2015-01-01

    As cord blood (CB) enables rapid access and tolerance to HLA mismatches, a number of unrelated CB transplants have reached 30,000. Such transplant activity has been the result of international accreditation programs maintaining highly qualified cord blood units (CBUs) reaching more than 600,000 CBUs stored worldwide. Efforts to increase stem cell content or engraftment rate of the graft by ex vivo expansion, modulation by molecules such as fucose, prostaglandin E2 derivative, complement CD26 inhibitors, or CXCR4/CXCL12 axis have been able to accelerate engraftment speed and rate. Furthermore, introduction of reduced intensity conditioning protocols, better HLA matching, and recognition of the importance of HLA-C have improved CB transplants success by decreasing transplant-related mortality. CB progenitor/stem cell content has been compared with adult stem cells revealing higher long-term repopulating capacity compared to bone marrow-mesenchymal stromal cells and lesser oncogenic potential than progenitor-induced stem cells. This chapter summarizes the advantages and disadvantages of CB compared to adult stem cells within the context of stem cell biology and transplantation.

  4. Stem cells to gametes: how far should we go?

    Science.gov (United States)

    Whittaker, Peter

    2007-03-01

    Murine embryonic stem cells have recently been shown to be capable of differentiating in vitro into oocytes or sperm. Should these findings be duplicated using human embryonic stem cells, this would raise a number of social and ethical concerns, some specific to these particular developments, others shared with other aspects of stem cell research. This review outlines the properties of stem cells and their conversion to gametes. Concerns raised include embryo destruction, quality of gametes derived in this way, possibility for children with two male biological parents, movement towards germ line gene therapy and 'designer babies', and the future impacts on health service provisions. It is important that public discussion of some of these issues should take place.

  5. Cartilage regeneration by chondrogenic induced adult stem cells in osteoarthritic sheep model.

    Science.gov (United States)

    Ude, Chinedu C; Sulaiman, Shamsul B; Min-Hwei, Ng; Hui-Cheng, Chen; Ahmad, Johan; Yahaya, Norhamdan M; Saim, Aminuddin B; Idrus, Ruszymah B H

    2014-01-01

    In this study, Adipose stem cells (ADSC) and bone marrow stem cells (BMSC), multipotent adult cells with the potentials for cartilage regenerations were induced to chondrogenic lineage and used for cartilage regenerations in surgically induced osteoarthritis in sheep model. Osteoarthritis was induced at the right knee of sheep by complete resection of the anterior cruciate ligament and medial meniscus following a 3-weeks exercise regimen. Stem cells from experimental sheep were culture expanded and induced to chondrogenic lineage. Test sheep received a single dose of 2 × 10(7) autologous PKH26-labelled, chondrogenically induced ADSCs or BMSCs as 5 mls injection, while controls received 5 mls culture medium. The proliferation rate of ADSCs 34.4 ± 1.6 hr was significantly higher than that of the BMSCs 48.8 ± 5.3 hr (P = 0.008). Chondrogenic induced BMSCs had significantly higher expressions of chondrogenic specific genes (Collagen II, SOX9 and Aggrecan) compared to chondrogenic ADSCs (P = 0.031, 0.010 and 0.013). Grossly, the treated knee joints showed regenerated de novo cartilages within 6 weeks post-treatment. On the International Cartilage Repair Society grade scores, chondrogenically induced ADSCs and BMSCs groups had significantly lower scores than controls (P = 0.0001 and 0.0001). Fluorescence of the tracking dye (PKH26) in the injected cells showed that they had populated the damaged area of cartilage. Histological staining revealed loosely packed matrixes of de novo cartilages and immunostaining demonstrated the presence of cartilage specific proteins, Collagen II and SOX9. Autologous chondrogenically induced ADSCs and BMSCs could be promising cell sources for cartilage regeneration in osteoarthritis.

  6. Cartilage regeneration by chondrogenic induced adult stem cells in osteoarthritic sheep model.

    Directory of Open Access Journals (Sweden)

    Chinedu C Ude

    Full Text Available OBJECTIVES: In this study, Adipose stem cells (ADSC and bone marrow stem cells (BMSC, multipotent adult cells with the potentials for cartilage regenerations were induced to chondrogenic lineage and used for cartilage regenerations in surgically induced osteoarthritis in sheep model. METHODS: Osteoarthritis was induced at the right knee of sheep by complete resection of the anterior cruciate ligament and medial meniscus following a 3-weeks exercise regimen. Stem cells from experimental sheep were culture expanded and induced to chondrogenic lineage. Test sheep received a single dose of 2 × 10(7 autologous PKH26-labelled, chondrogenically induced ADSCs or BMSCs as 5 mls injection, while controls received 5 mls culture medium. RESULTS: The proliferation rate of ADSCs 34.4 ± 1.6 hr was significantly higher than that of the BMSCs 48.8 ± 5.3 hr (P = 0.008. Chondrogenic induced BMSCs had significantly higher expressions of chondrogenic specific genes (Collagen II, SOX9 and Aggrecan compared to chondrogenic ADSCs (P = 0.031, 0.010 and 0.013. Grossly, the treated knee joints showed regenerated de novo cartilages within 6 weeks post-treatment. On the International Cartilage Repair Society grade scores, chondrogenically induced ADSCs and BMSCs groups had significantly lower scores than controls (P = 0.0001 and 0.0001. Fluorescence of the tracking dye (PKH26 in the injected cells showed that they had populated the damaged area of cartilage. Histological staining revealed loosely packed matrixes of de novo cartilages and immunostaining demonstrated the presence of cartilage specific proteins, Collagen II and SOX9. CONCLUSION: Autologous chondrogenically induced ADSCs and BMSCs could be promising cell sources for cartilage regeneration in osteoarthritis.

  7. Can one generate stable hyaline cartilage from adult mesenchymal stem cells? A developmental approach.

    Science.gov (United States)

    Hellingman, Catharine A; Koevoet, Wendy; van Osch, Gerjo J V M

    2012-11-01

    Chondrogenically differentiating bone marrow-derived mesenchymal stem cells (BMSCs) display signs of chondrocyte hypertrophy, such as production of collagen type X, MMP13 and alkaline phosphatase (ALPL). For cartilage reconstructions this is undesirable, as terminally differentiated cartilage produced by BMSCs mineralizes when implanted in vivo. Terminal differentiation is not restricted to BMSCs but is also encountered in chondrogenic differentiation of adipose-derived mesenchymal stem cells (MSCs) as well as embryonic stem cells, which by definition should be able to generate all types of tissues, including stable cartilage. Therefore, we propose that the currently used culture conditions may drive the cells towards terminal differentiation. In this manuscript we aim to review the literature, supplemented by our own data to answer the question, is it possible to generate stable hyaline cartilage from adult MSCs? We demonstrate that recently published methods for inhibiting terminal differentiation (through PTHrP, MMP13 or blocking phosphorylation of Smad1/5/8) result in cartilage formation with reduction of hypertrophic markers, although this does not reach the low level of stable chondrocytes. A set of hypertrophy markers should be included in future studies to characterize the phenotype more precisely. Finally, we used what is currently known in developmental biology about the differential development of hyaline and terminally differentiated cartilage to provide thought and insights to change current culture models for creating hyaline cartilage. Inhibiting terminal differentiation may not result in stable hyaline cartilage if the right balance of signals has not been created from the start of culture onwards. Copyright © 2011 John Wiley & Sons, Ltd.

  8. Plasmid-based generation of induced neural stem cells from adult human fibroblasts

    Directory of Open Access Journals (Sweden)

    Philipp Capetian

    2016-10-01

    Full Text Available Direct reprogramming from somatic to neural cell types has become an alternative to induced pluripotent stem cells. Most protocols employ viral expression systems, posing the risk of random genomic integration. Recent developments led to plasmid-based protocols, lowering this risk. However, these protocols either relied on continuous presence of a variety of small molecules or were only able to reprogram murine cells. We therefore established a reprogramming protocol based on vectors containing the Epstein-Barr virus (EBV-derived oriP/EBNA1 as well as the defined expression factors Oct3/4, Sox2, Klf4, L-myc, Lin28, and a small hairpin directed against p53. We employed a defined neural medium in combination with the neurotrophins bFGF, EGF and FGF4 for cultivation without the addition of small molecules. After reprogramming, cells demonstrated a temporary increase in the expression of endogenous Oct3/4. We obtained induced neural stem cells (iNSC 30 days after transfection. In contrast to previous results, plasmid vectors as well as a residual expression of reprogramming factors remained detectable in all cell lines. Cells showed a robust differentiation into neuronal (72% and glial cells (9% astrocytes, 6% oligodendrocytes. Despite the temporary increase of pluripotency-associated Oct3/4 expression during reprogramming, we did not detect pluripotent stem cells or non-neural cells in culture (except occasional residual fibroblasts. Neurons showed electrical activity and functional glutamatergic synapses. Our results demonstrate that reprogramming adult human fibroblasts to iNSC by plasmid vectors and basic neural medium without small molecules is possible and feasible. However, a full set of pluripotency-associated transcription factors may indeed result in the acquisition of a transient (at least partial pluripotent intermediate during reprogramming. In contrast to previous reports, the EBV-based plasmid system remained present and active inside

  9. Embryonic stem cells in pig and cattle

    DEFF Research Database (Denmark)

    Maddox-Hyttel, Poul; Wolf, Xenia Asbæk; Rasmussen, Mikkel Aabech

    2007-01-01

    Porcine and bovine cell lines derived from the inner cell mass (ICM) or epiblasts of blastocysts have been maintained over extended periods of time and characterized by morphology, identification of some stem cell markers and, in few cases, by production of chimaeric offspring. However, germ line...... transmission in chimaeras has never been obtained. Due to this incomplete characterization of the cell lines, the expression embryonic stem (ES)-like cells is presently used in pig and cattle. The ICM or epiblast can be isolated from the blastocyst by whole blastocyst culture, mechanical isolation......, or immunosurgery, and they are generally cultured on feeder cells. The resulting ES-like cells may be differentiated in vivo by chimaera and teratoma formation or in vitro by embryoid body formation and monolayer induction. It is likely that more well characterized and stable porcine and bovine ES cell lines...

  10. PPARs Expression in Adult Mouse Neural Stem Cells: Modulation of PPARs during Astroglial Differentiaton of NSC

    Directory of Open Access Journals (Sweden)

    A. Cimini

    2007-01-01

    Full Text Available PPAR isotypes are involved in the regulation of cell proliferation, death, and differentiation, with different roles and mechanisms depending on the specific isotype and ligand and on the differentiated, undifferentiated, or transformed status of the cell. Differentiation stimuli are integrated by key transcription factors which regulate specific sets of specialized genes to allow proliferative cells to exit the cell cycle and acquire specialized functions. The main differentiation programs known to be controlled by PPARs both during development and in the adult are placental differentiation, adipogenesis, osteoblast differentiation, skin differentiation, and gut differentiation. PPARs may also be involved in the differentiation of macrophages, brain, and breast. However, their functions in this cell type and organs still awaits further elucidation. PPARs may be involved in cell proliferation and differentiation processes of neural stem cells (NSC. To this aim, in this work the expression of the three PPAR isotypes and RXRs in NSC has been investigated.

  11. Surface Hydrophilicity of Poly(l-Lactide Acid Polymer Film Changes the Human Adult Adipose Stem Cell Architecture

    Directory of Open Access Journals (Sweden)

    Chiara Argentati

    2018-02-01

    Full Text Available Current knowledge indicates that the molecular cross-talk between stem cells and biomaterials guides the stem cells’ fate within a tissue engineering system. In this work, we have explored the effects of the interaction between the poly(l-lactide acid (PLLA polymer film and human adult adipose stem cells (hASCs, focusing on the events correlating the materials’ surface characteristics and the cells’ plasma membrane. hASCs were seeded on films of pristine PLLA polymer and on a PLLA surface modified by the radiofrequency plasma method under oxygen flow (PLLA+O2. Comparative experiments were performed using human bone-marrow mesenchymal stem cells (hBM-MSCs and human umbilical matrix stem cells (hUCMSCs. After treatment with oxygen-plasma, the surface of PLLA films became hydrophilic, whereas the bulk properties were not affected. hASCs cultured on pristine PLLA polymer films acquired a spheroid conformation. On the contrary, hASCs seeded on PLLA+O2 film surface maintained the fibroblast-like morphology typically observed on tissue culture polystyrene. This suggests that the surface hydrophilicity is involved in the acquisition of the spheroid conformation. Noteworthy, the oxygen treatment had no effects on hBM-MSC and hUCMSC cultures and both stem cells maintained the same shape observed on PLLA films. This different behavior suggests that the biomaterial-interaction is stem cell specific.

  12. Thyroid Hormone-Induced Activation of Notch Signaling is Required for Adult Intestinal Stem Cell Development During Xenopus Laevis Metamorphosis.

    Science.gov (United States)

    Hasebe, Takashi; Fujimoto, Kenta; Kajita, Mitsuko; Fu, Liezhen; Shi, Yun-Bo; Ishizuya-Oka, Atsuko

    2017-04-01

    In Xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (AE) cells appear concomitantly. They proliferate and differentiate to form the adult epithelium (Ep). Thyroid hormone (TH) is well established to trigger this remodeling by regulating the expression of various genes including Notch receptor. To study the role of Notch signaling, we have analyzed the expression of its components, including the ligands (DLL and Jag), receptor (Notch), and targets (Hairy), in the metamorphosing intestine by real-time reverse transcription-polymerase chain reaction and in situ hybridization or immunohistochemistry. We show that they are up-regulated during both natural and TH-induced metamorphosis in a tissue-specific manner. Particularly, Hairy1 is specifically expressed in the AE cells. Moreover, up-regulation of Hairy1 and Hairy2b by TH was prevented by treating tadpoles with a γ-secretase inhibitor (GSI), which inhibits Notch signaling. More importantly, TH-induced up-regulation of LGR5, an adult intestinal stem cell marker, was suppressed by GSI treatment. Our results suggest that Notch signaling plays a role in stem cell development by regulating the expression of Hairy genes during intestinal remodeling. Furthermore, we show with organ culture experiments that prolonged exposure of tadpole intestine to TH plus GSI leads to hyperplasia of secretory cells and reduction of absorptive cells. Our findings here thus provide evidence for evolutionarily conserved role of Notch signaling in intestinal cell fate determination but more importantly reveal, for the first time, an important role of Notch pathway in the formation of adult intestinal stem cells during vertebrate development. Stem Cells 2017;35:1028-1039. © 2016 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  13. Prion replication occurs in endogenous adult neural stem cells and alters their neuronal fate: involvement of endogenous neural stem cells in prion diseases.

    Directory of Open Access Journals (Sweden)

    Aroa Relaño-Ginès

    Full Text Available Prion diseases are irreversible progressive neurodegenerative diseases, leading to severe incapacity and death. They are characterized in the brain by prion amyloid deposits, vacuolisation, astrocytosis, neuronal degeneration, and by cognitive, behavioural and physical impairments. There is no treatment for these disorders and stem cell therapy therefore represents an interesting new approach. Gains could not only result from the cell transplantation, but also from the stimulation of endogenous neural stem cells (NSC or by the combination of both approaches. However, the development of such strategies requires a detailed knowledge of the pathology, particularly concerning the status of the adult neurogenesis and endogenous NSC during the development of the disease. During the past decade, several studies have consistently shown that NSC reside in the adult mammalian central nervous system (CNS and that adult neurogenesis occurs throughout the adulthood in the subventricular zone of the lateral ventricle or the Dentate Gyrus of the hippocampus. Adult NSC are believed to constitute a reservoir for neuronal replacement during normal cell turnover or after brain injury. However, the activation of this system does not fully compensate the neuronal loss that occurs during neurodegenerative diseases and could even contribute to the disease progression. We investigated here the status of these cells during the development of prion disorders. We were able to show that NSC accumulate and replicate prions. Importantly, this resulted in the alteration of their neuronal fate which then represents a new pathologic event that might underlie the rapid progression of the disease.

  14. Developing Mentors: Adult participation, practices, and learning in an out-of-school time STEM program

    Science.gov (United States)

    Scipio, Deana Aeolani

    This dissertation examines learning within an out-of-school time (OST) Science, Technology, Engineering, and Mathematics (STEM) broadening participation program. The dissertation includes an introduction, three empirical chapters (written as individual articles), and a conclusion. The dissertation context is a chemical oceanography OST program for middle school students called Project COOL---Chemical Oceanography Outside the Lab. The program was a collaboration between middle school OST programming, a learning sciences research laboratory, and a chemical oceanography laboratory. Both labs were located at a research-based university in the Pacific Northwest of the United States. Participants include 34 youth, 12 undergraduates, and five professional scientists. The dissertation data corpus includes six years of ethnographic field notes across three field sites, 400 hours of video and audio recordings, 40 hours of semi-structured interviews, and more than 100 participant generated artifacts. Analysis methods include comparative case analysis, cognitive mapping, semiotic cluster analysis, video interaction analysis, and discourse analysis. The first empirical article focuses on synthesizing productive programmatic features from four years of design-based research.. The second article is a comparative case study of three STEM mentors from non-dominant communities in the 2011 COOL OST Program. The third article is a comparative case study of undergraduates learning to be mentors in the 2014 COOL OST Program. Findings introduce Deep Hanging as a theory of learning in practice. Deep Hanging entails authentic tasks in rich contexts, providing access, capitalizing on opportunity, and building interpersonal relationships. Taken together, these three chapters illuminate the process of designing a rich OST learning environment and the kinds of learning in practice that occurred for adult learners learning to be mentors through their participation in the COOL OST program. In

  15. Stem cells

    NARCIS (Netherlands)

    Jukes, Jojanneke; Both, Sanne; Post, Janine; van Blitterswijk, Clemens; Karperien, Marcel; de Boer, Jan; van Blitterswijk, Clemens A.

    2008-01-01

    This chapter defines stem cells and their properties. It identifies the major differences between embryonic and adult stem cells. Stem cells can be defined by two properties: the ability to make identical copies of themselves and the ability to form other cell types of the body. These properties are

  16. Should deciduous teeth be preserved in adult patients? How about stem cells? Is it reasonable to preserve them?

    Directory of Open Access Journals (Sweden)

    Alberto Consolaro

    2016-04-01

    Full Text Available Abstract When seeking orthodontic treatment, many adolescents and adult patients present with deciduous teeth. Naturally, deciduous teeth will inevitably undergo exfoliation at the expected time or at a later time. Apoptosis is the biological trigger of root resorption. In adult patients, deciduous teeth should not be preserved, as they promote: infraocclusion, traumatic occlusion, occlusal trauma, diastemata and size as well as morphology discrepancy malocclusion. Orthodontic movement speeds root resorption up, and so do restoring or recontouring deciduous teeth in order to establish esthetics and function. Deciduous teeth cells are dying as a result of apoptosis, and their regeneration potential, which allows them to act as stem cells, is limited. On the contrary, adult teeth cells have a greater proliferative potential. All kinds of stem cell therapies are laboratory investigative non authorized trials.

  17. Hematopoietic Stem Cells Are the Major Source of Multilineage Hematopoiesis in Adult Animals.

    Science.gov (United States)

    Sawai, Catherine M; Babovic, Sonja; Upadhaya, Samik; Knapp, David J H F; Lavin, Yonit; Lau, Colleen M; Goloborodko, Anton; Feng, Jue; Fujisaki, Joji; Ding, Lei; Mirny, Leonid A; Merad, Miriam; Eaves, Connie J; Reizis, Boris

    2016-09-20

    Hematopoietic stem cells (HSCs) sustain long-term reconstitution of hematopoiesis in transplantation recipients, yet their role in the endogenous steady-state hematopoiesis remains unclear. In particular, recent studies suggested that HSCs provide a relatively minor contribution to immune cell development in adults. We directed transgene expression in a fraction of HSCs that maintained reconstituting activity during serial transplantations. Inducible genetic labeling showed that transgene-expressing HSCs gave rise to other phenotypic HSCs, confirming their top position in the differentiation hierarchy. The labeled HSCs rapidly contributed to committed progenitors of all lineages and to mature myeloid cells and lymphocytes, but not to B-1a cells or tissue macrophages. Importantly, labeled HSCs gave rise to more than two-thirds of all myeloid cells and platelets in adult mice, and this contribution could be accelerated by an induced interferon response. Thus, classically defined HSCs maintain immune cell development in the steady state and during systemic cytokine responses. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. A Sox Transcription Factor Is a Critical Regulator of Adult Stem Cell Proliferation in the Drosophila Intestine

    Directory of Open Access Journals (Sweden)

    Fanju W. Meng

    2015-11-01

    Full Text Available Adult organs and their resident stem cells are constantly facing the challenge of adapting cell proliferation to tissue demand, particularly in response to environmental stresses. Whereas most stress-signaling pathways are conserved between progenitors and differentiated cells, stem cells have the specific ability to respond by increasing their proliferative rate, using largely unknown mechanisms. Here, we show that a member of the Sox family of transcription factors in Drosophila, Sox21a, is expressed in intestinal stem cells (ISCs in the adult gut. Sox21a is essential for the proliferation of these cells during both normal epithelium turnover and repair. Its expression is induced in response to tissue damage, downstream of the Jun N-terminal kinase (JNK and extracellular signal-regulated kinase (ERK pathways, to promote ISC proliferation. Although short-lived, Sox21a mutant flies show no developmental defects, supporting the notion that this factor is a specific regulator of adult stem cell proliferation.

  19. Reserve stem cells: Differentiated cells reprogram to fuel repair, metaplasia, and neoplasia in the adult gastrointestinal tract.

    Science.gov (United States)

    Mills, Jason C; Sansom, Owen J

    2015-07-14

    It has long been known that differentiated cells can switch fates, especially in vitro, but only recently has there been a critical mass of publications describing the mechanisms adult, postmitotic cells use in vivo to reverse their differentiation state. We propose that this sort of cellular reprogramming is a fundamental cellular process akin to apoptosis or mitosis. Because reprogramming can invoke regenerative cells from mature cells, it is critical to the long-term maintenance of tissues like the pancreas, which encounter large insults during adulthood but lack constitutively active adult stem cells to repair the damage. However, even in tissues with adult stem cells, like the stomach and intestine, reprogramming may allow mature cells to serve as reserve ("quiescent") stem cells when normal stem cells are compromised. We propose that the potential downside to reprogramming is that it increases risk for cancers that occur late in adulthood. Mature, long-lived cells may have years of exposure to mutagens. Mutations that affect the physiological function of differentiated, postmitotic cells may lead to apoptosis, but mutations in genes that govern proliferation might not be selected against. Hence, reprogramming with reentry into the cell cycle might unmask those mutations, causing an irreversible progenitor-like, proliferative state. We review recent evidence showing that reprogramming fuels irreversible metaplastic and precancerous proliferation in the stomach and pancreas. Finally, we illustrate how we think reprogrammed differentiated cells are likely candidates as cells of origin for cancers of the intestine. Copyright © 2015, American Association for the Advancement of Science.

  20. Reserve stem cells: Reprogramming of differentiated cells fuels repair, metaplasia, and neoplasia in the adult gastrointestinal tract

    Science.gov (United States)

    Mills, Jason C.; Sansom, Owen J.

    2016-01-01

    It has long been known that differentiated cells can switch fates, especially in vitro, but only recently has there been a critical mass of publications describing the mechanisms adult, post-mitotic cells use in vivo to reverse their differentiation state. We propose that this sort of cellular reprogramming is a fundamental cellular process akin to apoptosis or mitosis. Because reprogramming can invoke regenerative cells from mature cells, it is critical to the longterm maintenance of tissues like the pancreas, which encounter large insults during adulthood but lack constitutively active adult stem cells to repair the damage. However, even in tissues with adult stem cells, like stomach and intestine, reprogramming may allow mature cells to serve as reserve (“quiescent”) stem cells when normal stem cells are compromised. We propose that the potential downside to reprogramming is that it increases risk for cancers that occur late in adulthood. Mature, long-lived cells may have years of exposure to mutagens. Mutations that affect the physiological function of differentiated, post-mitotic cells may lead to apoptosis, but mutations in genes that govern proliferation might not be selected against. Hence, reprogramming with reentry into the cell cycle might unmask those mutations, causing an irreversible progenitor-like, proliferative state. We review recent evidence showing that reprogramming fuels irreversible metaplastic and precancerous proliferations in stomach and pancreas. Finally, we illustrate how we think reprogrammed differentiated cells are likely candidates as cells of origin for cancers of the intestine. PMID:26175494

  1. Ex-Vivo Tissues Engineering Modeling for Reconstructive Surgery Using Human Adult Adipose Stem Cells and Polymeric Nanostructured Matrix.

    Science.gov (United States)

    Morena, Francesco; Argentati, Chiara; Calzoni, Eleonora; Cordellini, Marino; Emiliani, Carla; D'Angelo, Francesco; Martino, Sabata

    2016-03-31

    The major challenge for stem cell translation regenerative medicine is the regeneration of damaged tissues by creating biological substitutes capable of recapitulating the missing function in the recipient host. Therefore, the current paradigm of tissue engineering strategies is the combination of a selected stem cell type, based on their capability to differentiate toward committed cell lineages, and a biomaterial, that, due to own characteristics (e.g., chemical, electric, mechanical property, nano-topography, and nanostructured molecular components), could serve as active scaffold to generate a bio-hybrid tissue/organ. Thus, effort has been made on the generation of in vitro tissue engineering modeling. Here, we present an in vitro model where human adipose stem cells isolated from lipoaspirate adipose tissue and breast adipose tissue, cultured on polymeric INTEGRA ® Meshed Bilayer Wound Matrix (selected based on conventional clinical applications) are evaluated for their potential application for reconstructive surgery toward bone and adipose tissue. We demonstrated that human adipose stem cells isolated from lipoaspirate and breast tissue have similar stemness properties and are suitable for tissue engineering applications. Finally, the overall results highlighted lipoaspirate adipose tissue as a good source for the generation of adult adipose stem cells.

  2. NGF induces adult stem Leydig cells to proliferate and differentiate during Leydig cell regeneration.

    Science.gov (United States)

    Zhang, Lei; Wang, Huaxi; Yang, Yan; Liu, Hui; Zhang, Qihao; Xiang, Qi; Ge, Renshan; Su, Zhijian; Huang, Yadong

    2013-06-28

    Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was to examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful information for developing new potential therapies for PADAM (Partial Androgen Deficiency in the Aging Male). Copyright © 2013 Elsevier Inc. All rights reserved.

  3. EVI and MDS/EVI are required for adult intestinal stem cell formation during postembryonic vertebrate development.

    Science.gov (United States)

    Okada, Morihiro; Shi, Yun-Bo

    2018-01-01

    The gene ectopic viral integration site 1 (EVI) and its variant myelodysplastic syndrome 1 (MDS)/EVI encode zinc-finger proteins that have been recognized as important oncogenes in various types of cancer. In contrast to the established role of EVI and MDS/EVI in cancer development, their potential function during vertebrate postembryonic development, especially in organ-specific adult stem cells, is unclear. Amphibian metamorphosis is strikingly similar to postembryonic development around birth in mammals, with both processes taking place when plasma thyroid hormone (T3) levels are high. Using the T3-dependent metamorphosis in Xenopus tropicalis as a model, we show here that high levels of EVI and MDS/EVI are expressed in the intestine at the climax of metamorphosis and are induced by T3. By using the transcription activator-like effector nuclease gene editing technology, we have knocked out both EVI and MDS/EVI and have shown that EVI and MDS/EVI are not essential for embryogenesis and premetamorphosis in X. tropicalis On the other hand, knocking out EVI and MDS/EVI causes severe retardation in the growth and development of the tadpoles during metamorphosis and leads to tadpole lethality at the climax of metamorphosis. Furthermore, the homozygous-knockout animals have reduced adult intestinal epithelial stem cell proliferation at the end of metamorphosis (for the few that survive through metamorphosis) or during T3-induced metamorphosis. These findings reveal a novel role of EVI and/or MDS/EVI in regulating the formation and/or proliferation of adult intestinal adult stem cells during postembryonic development in vertebrates.-Okada, M., Shi, Y.-B. EVI and MDS/EVI are required for adult intestinal stem cell formation during postembryonic vertebrate development. © FASEB.

  4. A Novel View of the Adult Stem Cell Compartment From the Perspective of a Quiescent Population of Very Small Embryonic-Like Stem Cells.

    Science.gov (United States)

    Ratajczak, Mariusz Z; Ratajczak, Janina; Suszynska, Malwina; Miller, Donald M; Kucia, Magda; Shin, Dong-Myung

    2017-01-06

    Evidence has accumulated that adult hematopoietic tissues and other organs contain a population of dormant stem cells (SCs) that are more primitive than other, already restricted, monopotent tissue-committed SCs (TCSCs). These observations raise several questions, such as the developmental origin of these cells, their true pluripotent or multipotent nature, which surface markers they express, how they can be efficiently isolated from adult tissues, and what role they play in the adult organism. The phenotype of these cells and expression of some genes characteristic of embryonic SCs, epiblast SCs, and primordial germ cells suggests their early-embryonic deposition in developing tissues as precursors of adult SCs. In this review, we will critically discuss all these questions and the concept that small dormant SCs related to migratory primordial germ cells, described as very small embryonic-like SCs, are deposited during embryogenesis in bone marrow and other organs as a backup population for adult tissue-committed SCs and are involved in several processes related to tissue or organ rejuvenation, aging, and cancerogenesis. The most recent results on successful ex vivo expansion of human very small embryonic-like SC in chemically defined media free from feeder-layer cells open up new and exciting possibilities for their application in regenerative medicine. © 2017 American Heart Association, Inc.

  5. Store-Operated Calcium Entries Control Neural Stem Cell Self-Renewal in the Adult Brain Subventricular Zone.

    Science.gov (United States)

    Domenichini, Florence; Terrié, Elodie; Arnault, Patricia; Harnois, Thomas; Magaud, Christophe; Bois, Patrick; Constantin, Bruno; Coronas, Valérie

    2018-05-01

    The subventricular zone (SVZ) is the major stem cell niche in the brain of adult mammals. Within this region, neural stem cells (NSC) proliferate, self-renew and give birth to neurons and glial cells. Previous studies underlined enrichment in calcium signaling-related transcripts in adult NSC. Because of their ability to mobilize sustained calcium influxes in response to a wide range of extracellular factors, store-operated channels (SOC) appear to be, among calcium channels, relevant candidates to induce calcium signaling in NSC whose cellular activities are continuously adapted to physiological signals from the microenvironment. By Reverse Transcription Polymerase Chain Reaction (RT-PCR), Western blotting and immunocytochemistry experiments, we demonstrate that SVZ cells express molecular actors known to build up SOC, namely transient receptor potential canonical 1 (TRPC1) and Orai1, as well as their activator stromal interaction molecule 1 (STIM1). Calcium imaging reveals that SVZ cells display store-operated calcium entries. Pharmacological blockade of SOC with SKF-96365 or YM-58483 (also called BTP2) decreases proliferation, impairs self-renewal by shifting the type of SVZ stem cell division from symmetric proliferative to asymmetric, thereby reducing the stem cell population. Brain section immunostainings show that TRPC1, Orai1, and STIM1 are expressed in vivo, in SOX2-positive SVZ NSC. Injection of SKF-96365 in brain lateral ventricle diminishes SVZ cell proliferation and reduces the ability of SVZ cells to form neurospheres in vitro. The present study combining in vitro and in vivo approaches uncovers a major role for SOC in the control of SVZ NSC population and opens new fields of investigation for stem cell biology in health and disease. Stem Cells 2018;36:761-774. © AlphaMed Press 2018.

  6. Meis1 Is Required for Adult Mouse Erythropoiesis, Megakaryopoiesis and Hematopoietic Stem Cell Expansion.

    Directory of Open Access Journals (Sweden)

    Michelle Erin Miller

    Full Text Available Meis1 is recognized as an important transcriptional regulator in hematopoietic development and is strongly implicated in the pathogenesis of leukemia, both as a Hox transcription factor co-factor and independently. Despite the emerging recognition of Meis1's importance in the context of both normal and leukemic hematopoiesis, there is not yet a full understanding of Meis1's functions and the relevant pathways and genes mediating its functions. Recently, several conditional mouse models for Meis1 have been established. These models highlight a critical role for Meis1 in adult mouse hematopoietic stem cells (HSCs and implicate reactive oxygen species (ROS as a mediator of Meis1 function in this compartment. There are, however, several reported differences between these studies in terms of downstream progenitor populations impacted and effectors of function. In this study, we describe further characterization of a conditional knockout model based on mice carrying a loxP-flanked exon 8 of Meis1 which we crossed onto the inducible Cre localization/expression strains, B6;129-Gt(ROSA26Sor(tm1(Cre/ERTNat/J or B6.Cg-Tg(Mx1-Cre1Cgn/J. Findings obtained from these two inducible Meis1 knockout models confirm and extend previous reports of the essential role of Meis1 in adult HSC maintenance and expansion and provide new evidence that highlights key roles of Meis1 in both megakaryopoiesis and erythropoiesis. Gene expression analyses point to a number of candidate genes involved in Meis1's role in hematopoiesis. Our data additionally support recent evidence of a role of Meis1 in ROS regulation.

  7. Cellular Analysis of Adult Neural Stem Cells for Investigating Prion Biology.

    Science.gov (United States)

    Haigh, Cathryn L

    2017-01-01

    Traditional primary and secondary cell cultures have been used for the investigation of prion biology and disease for many years. While both types of cultures produce highly valid and immensely valuable results, they also have their limitations; traditional cell lines are often derived from cancers, therefore subject to numerous DNA changes, and primary cultures are labor-intensive and expensive to produce requiring sacrifice of many animals. Neural stem cell (NSC) cultures are a relatively new technology to be used for the study of prion biology and disease. While NSCs are subject to their own limitations-they are generally cultured ex vivo in environments that artificially force their growth-they also have their own unique advantages. NSCs retain the ability for self-renewal and can therefore be propagated in culture similarly to secondary cultures without genetic manipulation. In addition, NSCs are multipotent; they can be induced to differentiate into mature cells of central nervous system (CNS) linage. The combination of self-renewal and multipotency allows NSCs to be used as a primary cell line over multiple generations saving time, costs, and animal harvests, thus providing a valuable addition to the existing cell culture repertoire used for investigation of prion biology and disease. Furthermore, NSC cultures can be generated from mice of any genotype, either by embryonic harvest or harvest from adult brain, allowing gene expression to be studied without further genetic manipulation. This chapter describes a standard method of culturing adult NSCs and assays for monitoring NSC growth, migration, and differentiation and revisits basic reactive oxygen species detection in the context of NSC cultures.

  8. Lineage tracing in the adult mouse corneal epithelium supports the limbal epithelial stem cell hypothesis with intermittent periods of stem cell quiescence

    Directory of Open Access Journals (Sweden)

    Natalie J. Dorà

    2015-11-01

    Full Text Available The limbal epithelial stem cell (LESC hypothesis proposes that LESCs in the corneal limbus maintain the corneal epithelium both during normal homeostasis and wound repair. The alternative corneal epithelial stem cell (CESC hypothesis proposes that LESCs are only involved in wound repair and CESCs in the corneal epithelium itself maintain the corneal epithelium during normal homeostasis. We used tamoxifen-inducible, CreER-loxP lineage tracing to distinguish between these hypotheses. Clones of labelled cells were induced in adult CAGG-CreER;R26R-LacZ reporter mice and their distributions analysed after different chase periods. Short-lived clones, derived from labelled transient amplifying cells, were shed during the chase period and long-lived clones, derived from stem cells, expanded. At 6 weeks, labelled clones appeared at the periphery, extended centripetally as radial stripes and a few reached the centre by 14 weeks. Stripe numbers depended on the age of tamoxifen treatment. Stripes varied in length, some were discontinuous, few reached the centre and almost half had one end at the limbus. Similar stripes extended across the cornea in CAGG-CreER;R26R-mT/mG reporter mice. The distributions of labelled clones are inconsistent with the CESC hypothesis and support the LESC hypothesis if LESCs cycle between phases of activity and quiescence, each lasting several weeks.

  9. Adult hippocampus derived soluble factors induce a neuronal-like phenotype in mesenchymal stem cells.

    Science.gov (United States)

    Rivera, Francisco J; Sierralta, Walter D; Minguell, Jose J; Aigner, Ludwig

    2006-10-02

    Bone marrow-derived mesenchymal stem cells (MSCs) are not restricted in their differentiation fate to cells of the mesenchymal lineage. They acquire a neural phenotype in vitro and in vivo after transplantation in the central nervous system. Here we investigated whether soluble factors derived from different brain regions are sufficient to induce a neuronal phenotype in MSCs. We incubated bone marrow-derived MSCs in conditioned medium (CM) derived from adult hippocampus (HCM), cortex (CoCM) or cerebellum (CeCM) and analyzed the cellular morphology and the expression of neuronal and glial markers. In contrast to muscle derived conditioned medium, which served as control, conditioned medium derived from the different brain regions induced a neuronal morphology and the expression of the neuronal markers GAP-43 and neurofilaments in MSCs. Hippocampus derived conditioned medium had the strongest activity. It was independent of NGF or BDNF; and it was restricted to the neuronal differentiation fate, since no induction of the astroglial marker GFAP was observed. The work indicates that soluble factors present in the brain are sufficient to induce a neuronal phenotype in MSCs.

  10. FOXO3 Promotes Quiescence in Adult Muscle Stem Cells during the Process of Self-Renewal

    Directory of Open Access Journals (Sweden)

    Suchitra D. Gopinath

    2014-04-01

    Full Text Available Skeletal muscle stem cells, or “satellite cells” (SCs, are required for the regeneration of damaged muscle tissue. Although SCs self-renew during regeneration, the mechanisms that govern SC re-entry into quiescence remain elusive. We show that FOXO3, a member of the forkhead family of transcription factors, is expressed in quiescent SCs (QSCs. Conditional deletion of Foxo3 in QSCs impairs self-renewal and increases the propensity of SCs to adopt a differentiated fate. Transcriptional analysis of SCs lacking FOXO3 revealed a downregulation of Notch signaling, a key regulator of SC quiescence. Conversely, overexpression of Notch intracellular domain (NICD rescued the self-renewal deficit of FOXO3-deficient SCs. We show that FOXO3 regulates NOTCH1 and NOTCH3 receptor expression and that decreasing expression of NOTCH1 and NOTCH3 receptors phenocopies the effect of FOXO3 deficiency in SCs. We demonstrate that FOXO3, perhaps by activating Notch signaling, promotes the quiescent state during SC self-renewal in adult muscle regeneration.

  11. Ethical and Regulatory Challenges with Autologous Adult Stem Cells: A Comparative Review of International Regulations.

    Science.gov (United States)

    Lysaght, Tamra; Kerridge, Ian H; Sipp, Douglas; Porter, Gerard; Capps, Benjamin J

    2017-06-01

    Cell and tissue-based products, such as autologous adult stem cells, are being prescribed by physicians across the world for diseases and illnesses that they have neither been approved for or been demonstrated as safe and effective in formal clinical trials. These doctors often form part of informal transnational networks that exploit differences and similarities in the regulatory systems across geographical contexts. In this paper, we examine the regulatory infrastructure of five geographically diverse but socio-economically comparable countries with the aim of identifying similarities and differences in how these products are regulated and governed within clinical contexts. We find that while there are many subtle technical differences in how these regulations are implemented, they are sufficiently similar that it is difficult to explain why these practices appear more prevalent in some countries and not in others. We conclude with suggestions for how international governance frameworks might be improved to discourage the exploitation of vulnerable patient populations while enabling innovation in the clinical application of cellular therapies.

  12. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyoung Ho [Department of Otolaryngology Head and Neck Surgery, College of Medicine, Catholic University, Seoul (Korea, Republic of); Yeo, Sang Won, E-mail: swyeo@catholic.ac.kr [Department of Otolaryngology Head and Neck Surgery, College of Medicine, Catholic University, Seoul (Korea, Republic of); Troy, Frederic A., E-mail: fatroy@ucdavis.edu [Department of Biochemistry and Molecular Medicine, University of California, School of Medicine, Davis, CA 95616 (United States); Xiamen University, School of Medicine, Xiamen City (China)

    2014-10-17

    Highlights: • PolySia expressed on neurons primarily during early stages of neuronal development. • PolySia–NCAM is expressed on neural stem cells from adult guinea pig spiral ganglion. • PolySia is a biomarker that modulates neuronal differentiation in inner ear stem cells. - Abstract: During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia–NCAMs) modulate cell–cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia–NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb’s to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell–cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders.

  13. In vivo sensitivity of the embryonic and adult neural stem cell compartments to low-dose radiation

    International Nuclear Information System (INIS)

    Barazzuol, Lara; Jeggo, Penny A.

    2016-01-01

    The embryonic brain is radiation-sensitive, with cognitive deficits being observed after exposure to low radiation doses. Exposure of neonates to radiation can cause intracranial carcinogenesis. To gain insight into the basis underlying these outcomes, we examined the response of the embryonic, neonatal and adult brain to low-dose radiation, focusing on the neural stem cell compartments. This review summarizes our recent findings. At E13.5–14.5 the embryonic neocortex encompasses rapidly proliferating stem and progenitor cells. Exploiting mice with a hypomorphic mutation in DNA ligase IV (Lig4 Y288C ), we found a high level of DNA double-strand breaks (DSBs) at E14.5, which we attribute to the rapid proliferation. We observed endogenous apoptosis in Lig4 Y288C embryos and in WT embryos following exposure to low radiation doses. An examination of DSB levels and apoptosis in adult neural stem cell compartments, the subventricular zone (SVZ) and the subgranular zone (SGZ) revealed low DSB levels in Lig4 Y288C mice, comparable with the levels in differentiated neuronal tissues. We conclude that the adult SVZ does not incur high levels of DNA breakage, but sensitively activates apoptosis; apoptosis was less sensitively activated in the SGZ, and differentiated neuronal tissues did not activate apoptosis. P5/P15 mice showed intermediate DSB levels, suggesting that DSBs generated in the embryo can be transmitted to neonates and undergo slow repair. Interestingly, this analysis revealed a stage of high endogenous apoptosis in the neonatal SVZ. Collectively, these studies reveal that the adult neural stem cell compartment, like the embryonic counterpart, can sensitively activate apoptosis

  14. In vivo sensitivity of the embryonic and adult neural stem cell compartments to low-dose radiation.

    Science.gov (United States)

    Barazzuol, Lara; Jeggo, Penny A

    2016-08-01

    The embryonic brain is radiation-sensitive, with cognitive deficits being observed after exposure to low radiation doses. Exposure of neonates to radiation can cause intracranial carcinogenesis. To gain insight into the basis underlying these outcomes, we examined the response of the embryonic, neonatal and adult brain to low-dose radiation, focusing on the neural stem cell compartments. This review summarizes our recent findings. At E13.5-14.5 the embryonic neocortex encompasses rapidly proliferating stem and progenitor cells. Exploiting mice with a hypomorphic mutation in DNA ligase IV (Lig4(Y288C) ), we found a high level of DNA double-strand breaks (DSBs) at E14.5, which we attribute to the rapid proliferation. We observed endogenous apoptosis in Lig4(Y288C) embryos and in WT embryos following exposure to low radiation doses. An examination of DSB levels and apoptosis in adult neural stem cell compartments, the subventricular zone (SVZ) and the subgranular zone (SGZ) revealed low DSB levels in Lig4(Y288C) mice, comparable with the levels in differentiated neuronal tissues. We conclude that the adult SVZ does not incur high levels of DNA breakage, but sensitively activates apoptosis; apoptosis was less sensitively activated in the SGZ, and differentiated neuronal tissues did not activate apoptosis. P5/P15 mice showed intermediate DSB levels, suggesting that DSBs generated in the embryo can be transmitted to neonates and undergo slow repair. Interestingly, this analysis revealed a stage of high endogenous apoptosis in the neonatal SVZ. Collectively, these studies reveal that the adult neural stem cell compartment, like the embryonic counterpart, can sensitively activate apoptosis. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  15. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons

    International Nuclear Information System (INIS)

    Park, Kyoung Ho; Yeo, Sang Won; Troy, Frederic A.

    2014-01-01

    Highlights: • PolySia expressed on neurons primarily during early stages of neuronal development. • PolySia–NCAM is expressed on neural stem cells from adult guinea pig spiral ganglion. • PolySia is a biomarker that modulates neuronal differentiation in inner ear stem cells. - Abstract: During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia–NCAMs) modulate cell–cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia–NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb’s to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell–cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders

  16. Antiaging Effects of an Intensive Mind and Body Therapeutic Program through Enhancement of Telomerase Activity and Adult Stem Cell Counts.

    Science.gov (United States)

    Rao, Krishna S; Chakraharti, Swarup K; Dongare, Vaishali S; Chetana, K; Ramirez, Christina M; Koka, Prasad S; Deb, Kaushik D

    2015-01-01

    Key modalities of integrative medicine known to rejuvenate the mind and body are meditation, yoga, and controlled diet. It has been shown previously that intensive or prolonged mind and body therapies (MBT) may have beneficial effects on the well-being of healthy people and in patients. Telomerase activity and levels of peripheral blood adult pluripotent stem cells (PB-APSC) are reliable markers of long-term well-being that are known to decrease with age. The objective of this study is to understand the effect of our MBT program on telomerase activity and stem cells in blood collected from the participants. Here, we have investigated the effects of an intensive three weeks MBT retreat on telomerase activity and the peripheral blood stem cells in participants before and after the MBT. A total of 108 people were enrolled in the study; 38 men and 70 women (aged 18-90) randomly assigned for the study. Telomerase activity was greater in retreat participants at the end of the MBT retreat. About 45% of people showed more than one-fold increase of telomerase activity after our MBT program. Furthermore, about 27% of people showed more pronounced fold increase (2-fold) in telomerase activity after the MBT. In addition, a substantial percentage of people (about 90%) exhibited increased stem cell counts after the MBT. The data suggest increased telomerase activity and stem cells count in peripheral blood from MBT retreat participants that may lead to increased longevity and better quality of life at latter age.

  17. Fetal and adult hematopoietic stem cells require beta1 integrin function for colonizing fetal liver, spleen, and bone marrow

    DEFF Research Database (Denmark)

    Potocnik, A J; Brakebusch, C; Fässler, R

    2000-01-01

    hematolymphoid differentiation potential in vitro and in fetal organ cultures but were unable to seed fetal and adult hematopoietic tissues. Adult beta1 integrin null HSCs isolated from mice carrying loxP-tagged beta1 integrin alleles and ablated for beta1 integrin expression by retroviral cre transduction......Homing of hematopoietic stem cells (HSCs) into hematopoietic organs is a prerequisite for the establishment of hematopoiesis during embryogenesis and after bone marrow transplantation. We show that beta1 integrin-deficient HSCs from the para-aortic splanchnopleura and the fetal blood had...

  18. SRY-box-containing Gene 2 Regulation of Nuclear Receptor Tailless (Tlx) Transcription in Adult Neural Stem Cells

    OpenAIRE

    Shimozaki, Koji; Zhang, Chun-Li; Suh, Hoonkyo; Denli, Ahmet M.; Evans, Ronald M.; Gage, Fred H.

    2012-01-01

    Adult neurogenesis is maintained by self-renewable neural stem cells (NSCs). Their activity is regulated by multiple signaling pathways and key transcription factors. However, it has been unclear whether these factors interplay with each other at the molecular level. Here we show that SRY-box-containing gene 2 (Sox2) and nuclear receptor tailless (TLX) form a molecular network in adult NSCs. We observed that both Sox2 and TLX proteins bind to the upstream region of Tlx gene. Sox2 positively r...

  19. Isolation and functional interrogation of adult human prostate epithelial stem cells at single cell resolution.

    Science.gov (United States)

    Hu, Wen-Yang; Hu, Dan-Ping; Xie, Lishi; Li, Ye; Majumdar, Shyama; Nonn, Larisa; Hu, Hong; Shioda, Toshi; Prins, Gail S

    2017-08-01

    Using primary cultures of normal human prostate epithelial cells, we developed a novel prostasphere-based, label-retention assay that permits identification and isolation of stem cells at a single cell level. Their bona fide stem cell nature was corroborated using in vitro and in vivo regenerative assays and documentation of symmetric/asymmetric division. Robust WNT10B and KRT13 levels without E-cadherin or KRT14 staining distinguished individual stem cells from daughter progenitors in spheroids. Following FACS to isolate label-retaining stem cells from label-free progenitors, RNA-seq identified unique gene signatures for the separate populations which may serve as useful biomarkers. Knockdown of KRT13 or PRAC1 reduced sphere formation and symmetric self-renewal highlighting their role in stem cell maintenance. Pathways analysis identified ribosome biogenesis and membrane estrogen-receptor signaling enriched in stem cells with NF-ĸB signaling enriched in progenitors; activities that were biologically confirmed. Further, bioassays identified heightened autophagy flux and reduced metabolism in stem cells relative to progenitors. These approaches similarly identified stem-like cells from prostate cancer specimens and prostate, breast and colon cancer cell lines suggesting wide applicability. Together, the present studies isolate and identify unique characteristics of normal human prostate stem cells and uncover processes that maintain stem cell homeostasis in the prostate gland. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Isolation and functional interrogation of adult human prostate epithelial stem cells at single cell resolution

    Directory of Open Access Journals (Sweden)

    Wen-Yang Hu

    2017-08-01

    Full Text Available Using primary cultures of normal human prostate epithelial cells, we developed a novel prostasphere-based, label-retention assay that permits identification and isolation of stem cells at a single cell level. Their bona fide stem cell nature was corroborated using in vitro and in vivo regenerative assays and documentation of symmetric/asymmetric division. Robust WNT10B and KRT13 levels without E-cadherin or KRT14 staining distinguished individual stem cells from daughter progenitors in spheroids. Following FACS to isolate label-retaining stem cells from label-free progenitors, RNA-seq identified unique gene signatures for the separate populations which may serve as useful biomarkers. Knockdown of KRT13 or PRAC1 reduced sphere formation and symmetric self-renewal highlighting their role in stem cell maintenance. Pathways analysis identified ribosome biogenesis and membrane estrogen-receptor signaling enriched in stem cells with NF-ĸB signaling enriched in progenitors; activities that were biologically confirmed. Further, bioassays identified heightened autophagy flux and reduced metabolism in stem cells relative to progenitors. These approaches similarly identified stem-like cells from prostate cancer specimens and prostate, breast and colon cancer cell lines suggesting wide applicability. Together, the present studies isolate and identify unique characteristics of normal human prostate stem cells and uncover processes that maintain stem cell homeostasis in the prostate gland.

  1. Islet neogenesis potential of human adult stem cells and its applications in cell replacement therapy for diabetes

    Directory of Open Access Journals (Sweden)

    Bhonde RR

    2008-11-01

    Full Text Available In recent years regenerative biology has reached to greater heights due to its therapeutic potential in treating degenerative diseases; as they are not curable by modern medicine. With the advent of research in stem cells and developmental biology the regenerative potential of adult resident stem cells is becoming clearer. The long term objective of regenerative medicine or cell therapy is to treat patients with their own stem cells. These stem cells could be derived from the diseased organs such as skin, liver, pancreas etc. or from reservoirs of multipotent stem cells such as bone marrow or cord blood.Manipulating the ability of tissue resident stem cells as well as from multipotent reservoirs such as bone marrow, umbilical cord and cord blood to give rise to endocrine cells may open new avenues in the treatment of diabetes. A better understanding of stem cell biology would almost certainly allow for the establishment of efficient and reliable cell transplantation experimental programs in the clinic. We show here that multipotent mesenchymal stem cells can be isolated from various sources such as the bone marrow, placenta, umbilical cord. Upon stimulation with specific growth factors they differentiate into islet like clusters (ILCs. When ILCs obtained from the above mentioned sources were transplanted in experimental diabetic mice, restoration of normoglycemia was observed within three weeks of transplantation with concomitant increase in the body weight. These euglycemic mice exhibited normal glucose tolerance test indicating normal utilization of glucose. Allthough the MSCs isolated from all the sources had the same characteristics; they showed significant differences in their islet differentiation potential. ILCs isolated for the human bone marrow did not show any pancreatic hormones in vitro, but upon transplantation they matured into insulin and somatostatin producing hormones. Placental MSCs as well as ILCs showed insulin trascripts

  2. Running rescues defective adult neurogenesis by shortening the length of the cell cycle of neural stem and progenitor cells.

    Science.gov (United States)

    Farioli-Vecchioli, Stefano; Mattera, Andrea; Micheli, Laura; Ceccarelli, Manuela; Leonardi, Luca; Saraulli, Daniele; Costanzi, Marco; Cestari, Vincenzo; Rouault, Jean-Pierre; Tirone, Felice

    2014-07-01

    Physical exercise increases the generation of new neurons in adult neurogenesis. However, only few studies have investigated the beneficial effects of physical exercise in paradigms of impaired neurogenesis. Here, we demonstrate that running fully reverses the deficient adult neurogenesis within the hippocampus and subventricular zone of the lateral ventricle, observed in mice lacking the antiproliferative gene Btg1. We also evaluated for the first time how running influences the cell cycle kinetics of stem and precursor subpopulations of wild-type and Btg1-null mice, using a new method to determine the cell cycle length. Our data show that in wild-type mice running leads to a cell cycle shortening only of NeuroD1-positive progenitor cells. In contrast, in Btg1-null mice, physical exercise fully reactivates the defective hippocampal neurogenesis, by shortening the S-phase length and the overall cell cycle duration of both neural stem (glial fibrillary acidic protein(+) and Sox2(+)) and progenitor (NeuroD1(+)) cells. These events are sufficient and necessary to reactivate the hyperproliferation observed in Btg1-null early-postnatal mice and to expand the pool of adult neural stem and progenitor cells. Such a sustained increase of cell proliferation in Btg1-null mice after running provides a long-lasting increment of proliferation, differentiation, and production of newborn neurons, which rescues the impaired pattern separation previously identified in Btg1-null mice. This study shows that running positively affects the cell cycle kinetics of specific subpopulations of newly generated neurons and suggests that the plasticity of neural stem cells without cell cycle inhibitory control is reactivated by running, with implications for the long-term modulation of neurogenesis. © 2014 AlphaMed Press.

  3. Endometrial regeneration using autologous adult stem cells followed by conception by in vitro fertilization in a patient of severe Asherman′s syndrome

    Directory of Open Access Journals (Sweden)

    Chaitanya B Nagori

    2011-01-01

    Full Text Available In a woman with severe Asherman′s syndrome, curettage followed by placement of intrauterine contraceptive device (IUCD (IUCD with cyclical hormonal therapy was tried for 6 months, for development of the endometrium. When this failed, autologous stem cells were tried as an alternative therapy. From adult autologous stem cells isolated from patient′s own bone marrow, endometrial angiogenic stem cells were separated using immunomagnetic isolation. These cells were placed in the endometrial cavity under ultrasound guidance after curettage. Patient was then given cyclical hormonal therapy. Endometrium was assessed intermittently on ultrasound. On development of endometrium with a thickness of 8 mm and good vascularity, in vitro fertilization and embryo transfer was done. This resulted in positive biochemical pregnancy followed by confirmation of gestational sac, yolk sac, and embryonic pole with cardiac activity on ultrasound. Endometrial angiogenic stem cells isolated from autologous adult stem cells could regenerate injured endometrium not responding to conventional treatment for Asherman′s syndrome.

  4. Second neoplasms in adult patients submitted to haematopoietic stem cell transplantation.

    Science.gov (United States)

    Torrent, Anna; Ferrá, Christelle; Morgades, Mireia; Jiménez, María-José; Sancho, Juan-Manuel; Vives, Susana; Batlle, Montserrat; Moreno, Miriam; Xicoy, Blanca; Oriol, Albert; Ibarra, Gladys; Ribera, Josep-Maria

    2018-06-08

    Patients submitted to haematopoietic stem cell transplantation (HSCT) are at increased risk of late complications, such as second neoplasm (SN). The incidence and risk factors of SN in patients receiving HSCT at a single centre were analysed. The follow-up of adult patients who received a first HSCT (autologous [auto-HSCT] or allogeneic [allo-HSCT]) between January 2000 and December 2015 was reviewed. We collected their demographic characteristics, the primary disease and type of HSCT, and analysed the cumulative incidence of SN and their risk factors. Of 699 transplanted patients (auto-HSCT, n=451; allo-HSCT, n=248), 42 (6%) developed SN (17 haematological and 25 solid), 31 post-auto-HSCT and 11 post-allo-HSCT. Haematologic SN were more frequent after auto-HSCT than after allo-HSCT. The median time between HSCT and SN was 4.09 years [range 0.07-13.15], with no differences between auto-HSCT and allo-HSCT. The cumulative incidence of SN was 5% (95% CI 3-6) at 5 years, 7% (95% CI 5-10) at 10 years and 11% (95% CI 8-15) at 15 years, without differences according to the type of HSCT. Only the age over 40 years correlated with an increased risk of SN. In this series, the incidence of post-HSCT SN was similar to that previously described. Patients submitted to an auto-HSCT showed a higher frequency of haematologic SN. A higher incidence of SN was detected in patients older than 40 at the time of HSCT. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  5. The effect of cannabichromene on adult neural stem/progenitor cells.

    Science.gov (United States)

    Shinjyo, Noriko; Di Marzo, Vincenzo

    2013-11-01

    Apart from the psychotropic compound Δ(9)-tetrahydrocannabinol (THC), evidence suggests that other non-psychotropic phytocannabinoids are also of potential clinical use. This study aimed at elucidating the effect of major non-THC phytocannabinoids on the fate of adult neural stem progenitor cells (NSPCs), which are an essential component of brain function in health as well as in pathology. We tested three compounds: cannabidiol, cannabigerol, and cannabichromene (CBC), and found that CBC has a positive effect on the viability of mouse NSPCs during differentiation in vitro. The expression of NSPC and astrocyte markers nestin and Glial fibrillary acidic protein (GFAP), respectively, was up- and down-regulated, respectively. CBC stimulated ERK1/2 phosphorylation; however, this effect had a slower onset in comparison to typical MAPK stimulation. A MEK inhibitor, U0126, antagonized the up-regulation of nestin but not the down-regulation of GFAP. Based on a previous report, we studied the potential involvement of the adenosine A1 receptor in the effect of CBC on these cells and found that the selective adenosine A1 receptor antagonist, DPCPX, counteracted both ERK1/2 phosphorylation and up-regulation of nestin by CBC, indicating that also adenosine is involved in these effects of CBC, but possibly not in CBC inhibitory effect on GFAP expression. Next, we measured ATP levels as an equilibrium marker of adenosine and found higher ATP levels during differentiation of NSPCs in the presence of CBC. Taken together, our results suggest that CBC raises the viability of NSPCs while inhibiting their differentiation into astroglia, possibly through up-regulation of ATP and adenosine signalling. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Macrophages contribute to the cyclic activation of adult hair follicle stem cells

    DEFF Research Database (Denmark)

    Castellana, Donatello; Paus, Ralf; Perez-Moreno, Mirna

    2014-01-01

    Skin epithelial stem cells operate within a complex signaling milieu that orchestrates their lifetime regenerative properties. The question of whether and how immune cells impact on these stem cells within their niche is not well understood. Here we show that skin-resident macrophages decrease in...

  7. Single-Cell Transcriptomic Analysis Defines Heterogeneity and Transcriptional Dynamics in the Adult Neural Stem Cell Lineage

    Directory of Open Access Journals (Sweden)

    Ben W. Dulken

    2017-01-01

    Full Text Available Neural stem cells (NSCs in the adult mammalian brain serve as a reservoir for the generation of new neurons, oligodendrocytes, and astrocytes. Here, we use single-cell RNA sequencing to characterize adult NSC populations and examine the molecular identities and heterogeneity of in vivo NSC populations. We find that cells in the NSC lineage exist on a continuum through the processes of activation and differentiation. Interestingly, rare intermediate states with distinct molecular profiles can be identified and experimentally validated, and our analysis identifies putative surface markers and key intracellular regulators for these subpopulations of NSCs. Finally, using the power of single-cell profiling, we conduct a meta-analysis to compare in vivo NSCs and in vitro cultures, distinct fluorescence-activated cell sorting strategies, and different neurogenic niches. These data provide a resource for the field and contribute to an integrative understanding of the adult NSC lineage.

  8. Quiescent Oct4+ Neural Stem Cells (NSCs) Repopulate Ablated Glial Fibrillary Acidic Protein+ NSCs in the Adult Mouse Brain.

    Science.gov (United States)

    Reeve, Rachel L; Yammine, Samantha Z; Morshead, Cindi M; van der Kooy, Derek

    2017-09-01

    Adult primitive neural stem cells (pNSCs) are a rare population of glial fibrillary acidic protein (GFAP) - Oct4 + cells in the mouse forebrain subependymal zone bordering the lateral ventricles that give rise to clonal neurospheres in leukemia inhibitory factor in vitro. pNSC neurospheres can be passaged to self-renew or give rise to GFAP + NSCs that form neurospheres in epidermal growth factor and fibroblast growth factor 2, which we collectively refer to as definitive NSCs (dNSCs). Label retention experiments using doxycycline-inducible histone-2B (H2B)-green fluorescent protein (GFP) mice and several chase periods of up to 1 year quantified the adult pNSC cell cycle time as 3-5 months. We hypothesized that while pNSCs are not very proliferative at baseline, they may exist as a reserve pool of NSCs in case of injury. To test this function of pNSCs, we obtained conditional Oct4 knockout mice, Oct4 fl/fl ;Sox1 Cre (Oct4 CKO ), which do not yield adult pNSC-derived neurospheres. When we ablated the progeny of pNSCs, namely all GFAP + dNSCs, in these Oct4 CKO mice, we found that dNSCs did not recover as they do in wild-type mice, suggesting that pNSCs are necessary for dNSC repopulation. Returning to the H2B-GFP mice, we observed that the cytosine β-d-arabinofuranoside ablation of proliferating cells including dNSCs-induced quiescent pNSCs to proliferate and significantly dilute their H2B-GFP label. In conclusion, we demonstrate that pNSCs are the most quiescent stem cells in the adult brain reported to date and that their lineage position upstream of GFAP + dNSCs allows them to repopulate a depleted neural lineage. Stem Cells 2017;35:2071-2082. © 2017 AlphaMed Press.

  9. A balance of Mad and Myc expression dictates larval cell apoptosis and adult stem cell development during Xenopus intestinal metamorphosis.

    Science.gov (United States)

    Okada, Morihiro; Miller, Thomas C; Wen, Luan; Shi, Yun-Bo

    2017-05-11

    The Myc/Mad/Max network has long been shown to be an important factor in regulating cell proliferation, death and differentiation in diverse cell types. In general, Myc-Max heterodimers activate target gene expression to promote cell proliferation, although excess of c-Myc can also induce apoptosis. In contrast, Mad competes against Myc to form Mad-Max heterodimers that bind to the same target genes to repress their expression and promote differentiation. The role of the Myc/Mad/Max network during vertebrate development, especially, the so-called postembryonic development, a period around birth in mammals, is unclear. Using thyroid hormone (T3)-dependent Xenopus metamorphosis as a model, we show here that Mad1 is induced by T3 in the intestine during metamorphosis when larval epithelial cell death and adult epithelial stem cell development take place. More importantly, we demonstrate that Mad1 is expressed in the larval cells undergoing apoptosis, whereas c-Myc is expressed in the proliferating adult stem cells during intestinal metamorphosis, suggesting that Mad1 may have a role in cell death during development. By using transcription activator-like effector nuclease-mediated gene-editing technology, we have generated Mad1 knockout Xenopus animals. This has revealed that Mad1 is not essential for embryogenesis or metamorphosis. On the other hand, consistent with its spatiotemporal expression profile, Mad1 knockout leads to reduced larval epithelial apoptosis but surprisingly also results in increased adult stem cell proliferation. These findings not only reveal a novel role of Mad1 in regulating developmental cell death but also suggest that a balance of Mad and Myc controls cell fate determination during adult organ development.

  10. Human-Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells as an Individual-Specific and Renewable Source of Adult Stem Cells.

    Science.gov (United States)

    Sequiera, Glen Lester; Saravanan, Sekaran; Dhingra, Sanjiv

    2017-01-01

    This chapter deals with the employment of human-induced pluripotent stem cells (hiPSCs) as a candidate to differentiate into mesenchymal stem cells (MSCs). This would enable to help establish a regular source of human MSCs with the aim of avoiding the problems associated with procuring the MSCs either from different healthy individuals or patients, limited extraction potentials, batch-to-batch variations or from diverse sources such as bone marrow or adipose tissue. The procedures described herein allow for a guided and ensured approach for the regular maintenance of hiPSCs and their subsequent differentiation into MSCs using the prescribed medium. Subsequently, an easy protocol for the successive isolation and purification of the hiPSC-differentiated MSCs is outlined, which is carried out through passaging and can be further sorted through flow cytometry. Further, the maintenance and expansion of the resultant hiPSC-differentiated MSCs using appropriate characterization techniques, i.e., Reverse-transcription PCR and immunostaining is also elaborated. The course of action has been deliberated keeping in mind the awareness and the requisites available to even beginner researchers who mostly have access to regular consumables and medium components found in the general laboratory.

  11. How closely does stem growth of adult beech (Fagus sylvatica) relate to net carbon gain under experimentally enhanced ozone stress?

    International Nuclear Information System (INIS)

    Kitao, Mitsutoshi; Winkler, J. Barbro; Löw, Markus; Nunn, Angela J.; Kuptz, Daniel; Häberle, Karl-Heinz; Reiter, Ilja M.; Matyssek, Rainer

    2012-01-01

    The hypothesis was tested that O 3 -induced changes in leaf-level photosynthetic parameters have the capacity of limiting the seasonal photosynthetic carbon gain of adult beech trees. To this end, canopy-level photosynthetic carbon gain and respiratory carbon loss were assessed in European beech (Fagus sylvatica) by using a physiologically based model, integrating environmental and photosynthetic parameters. The latter were derived from leaves at various canopy positions under the ambient O 3 regime, as prevailing at the forest site (control), or under an experimental twice-ambient O 3 regime (elevated O 3 ), as released through a free-air canopy O 3 fumigation system. Gross carbon gain at the canopy-level declined by 1.7%, while respiratory carbon loss increased by 4.6% under elevated O 3 . As this outcome only partly accounts for the decline in stem growth, O 3 -induced changes in allocation are referred to and discussed as crucial in quantitatively linking carbon gain with stem growth. - Highlights: ► We model O 3 -induced changes in the photosynthetic carbon gain of adult beech trees. ► Elevated O 3 decreases gross carbon gain but increases respiratory carbon loss. ► Reduction in net carbon gain only partly accounts for the decline in stem growth. ► O 3 effects on the whole-tree allocation is crucial in addition to carbon gains. - Reduction in net carbon gain at the canopy level only partly accounts for the decline in stem growth under elevated ozone.

  12. Word-stem priming and recognition in type 2 diabetes mellitus, Alzheimer's disease patients and healthy older adults.

    Science.gov (United States)

    Redondo, María Teresa; Beltrán-Brotóns, José Luís; Reales, José Manuel; Ballesteros, Soledad

    2015-11-01

    The present study investigated (a) whether the pattern of performance on implicit and explicit memory of patients with type 2 diabetes mellitus (DM2) is more similar to those of patients with Alzheimer's disease (AD) or to cognitively normal older adults and (b) whether glycosylated hemoglobin levels (a measure of glucose regulation) are related to performance on the two memory tasks, implicit word-stem completion and "old-new" recognition. The procedures of both memory tasks included encoding and memory test phases separated by a short delay. Three groups of participants (healthy older adults, DM2 patients and AD patients) completed medical and psychological assessments and performed both memory tasks on a computer. The results of the word-stem completion task showed similar implicit memory in the three groups. By contrast, explicit recognition of the three groups differed. Implicit memory was not affected by either normal or pathological aging, but explicit memory deteriorated in the two groups of patients, especially in AD patients, showing a severe impairment compared to the cognitively healthy older adults. Importantly, glycosylated hemoglobin levels were not related to performance on either implicit or explicit memory tasks. These findings revealed a clear dissociation between explicit and implicit memory tasks in normal and pathological aging. Neuropsychologists and clinicians working with TM2 patients should be aware that the decline of voluntary, long-term explicit memory could have a negative impact on their treatment management. By contrast, the intact implicit memory of the two clinical groups could be used in rehabilitation.

  13. Induced pluripotent stem cells in research and therapy of diseases: review article

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Noori Daloii

    2014-10-01

    Full Text Available Differentiated cells can change to embryonic stem cells by reprograming. Generation of induced pluripotent stem cells (iPSCs has revolutionized the field of regenerative and personalized medicine. iPSCs can self-renew and differentiate into many cell types. iPSC cells offer a potentially unlimited source for targeted differentiation. Through the expression of a set of transcription factors, iPSCs can be generated from different kinds of embryonic and adult cells. This technology for the first time enabled the researchers to take differentiated cells from an individual, and convert them to another cell type of interest, which is particularly to that person. When the set of master transcription factors containing OCT4, SOX2, KLF4, and MYC is expressed ectopically in somatic cells, the transcriptional network is propelled to organize itself in such a way as to maintenance a pluripotent state. Since iPSCs are similar to Embryonic Stem Cell (ESC, they can be considered as sources for modeling different diseases. iPSCs which are induced from somatic cells of patient can be useful for screening and drugs selection, and also introduce treatment via grafting the cells. Although this technology has been successful in different fields, the tumorigenesis of viral vectors during induction of reprogramming is a major challenge. Nevertheless, iPSCs are valuable for clinical applications and research. By discovery of these cells many challenges related to the safety, efficacy, and bioethics of ESCs are solved. Pluripotency is defined in two aspect of functional and molecular, by which functional regards the capacity of cell is generate three kinds of embryonic layers and germ line, and molecular aspect regards the identifying of molecules and genes that support functional features. Identification of these genes has been placed at the center of fields related to development and stem cell research. In this review, we discuss the process of generation of these

  14. Generation of an induced pluripotent stem cell line from an adult male with 45,X/46,XY mosaicism

    Directory of Open Access Journals (Sweden)

    Yumei Luo

    2018-03-01

    Full Text Available Turner syndrome (TS with 45,X/46,XY mosaic karyotype is a rare sex chromosome disorder with an occurrence of 0.15‰ at birth. We report the generation of an induced pluripotent stem cell (iPSC line from peripheral blood mononuclear cells of a Chinese adult male with 45,X/46,XY mosaicism. The iPSC line retains the original 45,X/46,XY mosaic karyotype, expresses pluripotency markers and undergoes trilineage differentiation. Therefore, it offers an unprecedented cellular model to investigate the profound symptoms like infertility of TS in the male, and serve as a useful tool to develop therapies for the disease.

  15. Direct Activation of Amidohydrolase Domain-Containing 1 Gene by Thyroid Hormone Implicates a Role in the Formation of Adult Intestinal Stem Cells During Xenopus Metamorphosis.

    Science.gov (United States)

    Okada, Morihiro; Miller, Thomas C; Fu, Liezhen; Shi, Yun-Bo

    2015-09-01

    The T3-dependent anuran metamorphosis resembles postembryonic development in mammals, the period around birth when plasma T3 levels peak. In particular, the remodeling of the intestine during metamorphosis mimics neonatal intestinal maturation in mammals when the adult intestinal epithelial self-renewing system is established. We have been using intestinal metamorphosis to investigate how the organ-specific adult stem cells are formed during vertebrate development. Early studies in Xenopus laevis have shown that this process involves complete degeneration of the larval epithelium and de novo formation of adult stem cells. A tissue-specific microarray analysis of intestinal gene expression during Xenopus laevis metamorphosis has identified a number of candidate stem cell genes. Here we have carried out detailed analyses of one such gene, amidohydrolase domain containing 1 (AMDHD1) gene, which encodes an enzyme in the histidine catabolic pathway. We show that AMDHD1 is exclusively expressed in the proliferating adult epithelial stem cells during metamorphosis with little expression in other intestinal tissues. We further provide evidence that T3 activates AMDHD1 gene expression directly at the transcription level through T3 receptor binding to the AMDHD1 gene in the intestine. In addition, we have reported earlier that histidine ammonia-lyase gene, another gene in histidine catabolic pathway, is similarly regulated by T3 in the intestine. These results together suggest that histidine catabolism plays a critical role in the formation and/or proliferation of adult intestinal stem cells during metamorphosis.

  16. Induced Neural Stem Cells Achieve Long-Term Survival and Functional Integration in the Adult Mouse Brain

    Directory of Open Access Journals (Sweden)

    Kathrin Hemmer

    2014-09-01

    Full Text Available Differentiated cells can be converted directly into multipotent neural stem cells (i.e., induced neural stem cells [iNSCs]. iNSCs offer an attractive alternative to induced pluripotent stem cell (iPSC technology with regard to regenerative therapies. Here, we show an in vivo long-term analysis of transplanted iNSCs in the adult mouse brain. iNSCs showed sound in vivo long-term survival rates without graft overgrowths. The cells displayed a neural multilineage potential with a clear bias toward astrocytes and a permanent downregulation of progenitor and cell-cycle markers, indicating that iNSCs are not predisposed to tumor formation. Furthermore, the formation of synaptic connections as well as neuronal and glial electrophysiological properties demonstrated that differentiated iNSCs migrated, functionally integrated, and interacted with the existing neuronal circuitry. We conclude that iNSC long-term transplantation is a safe procedure; moreover, it might represent an interesting tool for future personalized regenerative applications.

  17. Induced neural stem cells achieve long-term survival and functional integration in the adult mouse brain.

    Science.gov (United States)

    Hemmer, Kathrin; Zhang, Mingyue; van Wüllen, Thea; Sakalem, Marna; Tapia, Natalia; Baumuratov, Aidos; Kaltschmidt, Christian; Kaltschmidt, Barbara; Schöler, Hans R; Zhang, Weiqi; Schwamborn, Jens C

    2014-09-09

    Differentiated cells can be converted directly into multipotent neural stem cells (i.e., induced neural stem cells [iNSCs]). iNSCs offer an attractive alternative to induced pluripotent stem cell (iPSC) technology with regard to regenerative therapies. Here, we show an in vivo long-term analysis of transplanted iNSCs in the adult mouse brain. iNSCs showed sound in vivo long-term survival rates without graft overgrowths. The cells displayed a neural multilineage potential with a clear bias toward astrocytes and a permanent downregulation of progenitor and cell-cycle markers, indicating that iNSCs are not predisposed to tumor formation. Furthermore, the formation of synaptic connections as well as neuronal and glial electrophysiological properties demonstrated that differentiated iNSCs migrated, functionally integrated, and interacted with the existing neuronal circuitry. We conclude that iNSC long-term transplantation is a safe procedure; moreover, it might represent an interesting tool for future personalized regenerative applications. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Direct Reprogramming of Adult Human Somatic Stem Cells Into Functional Neurons Using Sox2, Ascl1, and Neurog2

    Directory of Open Access Journals (Sweden)

    Jessica Alves de Medeiros Araújo

    2018-06-01

    Full Text Available Reprogramming of somatic cells into induced pluripotent stem cells (iPS or directly into cells from a different lineage, including neurons, has revolutionized research in regenerative medicine in recent years. Mesenchymal stem cells are good candidates for lineage reprogramming and autologous transplantation, since they can be easily isolated from accessible sources in adult humans, such as bone marrow and dental tissues. Here, we demonstrate that expression of the transcription factors (TFs SRY (sex determining region Y-box 2 (Sox2, Mammalian achaete-scute homolog 1 (Ascl1, or Neurogenin 2 (Neurog2 is sufficient for reprogramming human umbilical cord mesenchymal stem cells (hUCMSC into induced neurons (iNs. Furthermore, the combination of Sox2/Ascl1 or Sox2/Neurog2 is sufficient to reprogram up to 50% of transfected hUCMSCs into iNs showing electrical properties of mature neurons and establishing synaptic contacts with co-culture primary neurons. Finally, we show evidence supporting the notion that different combinations of TFs (Sox2/Ascl1 and Sox2/Neurog2 may induce multiple and overlapping neuronal phenotypes in lineage-reprogrammed iNs, suggesting that neuronal fate is determined by a combination of signals involving the TFs used for reprogramming but also the internal state of the converted cell. Altogether, the data presented here contribute to the advancement of techniques aiming at obtaining specific neuronal phenotypes from lineage-converted human somatic cells to treat neurological disorders.

  19. ALLOGENEIC STEM CELL TRANSPLANTATION FOR ADULT PATIENTS WITH ACUTE LEUKEMIA – 14 YEARS EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Jože Pretnar

    2004-12-01

    Full Text Available Background. This study was designed to evaluate the impact of various prognostic factors on long-term survival and event free survival after allogeneic hematopoietic stem cell transplantation for patients with acute leukemia.Methods and patients. Between years 1989 and 2002 44 patients with acute leukemia (30 with AML and 14 with ALL were transplanted. Survival curves using the Kaplan-Meier method were calculated for patients transplanted with two different sources of stem cells – bone marrow and peripheral blood and separately for patients with female donor.Results. Estimated 10 years survival for AML is 43% and 64% for ALL patients which is not statistically different. There are no significant differences in outcome regarding source of stem cells and in donors’ gender.Conclusions. To conclude, our results show that neither source of stem cells nor donor’s gender has impact on the long-term survival after hematopoietic stem cell transplantation. As published previously patients transplanted beyond the first remission have significantly worse outcome.

  20. Human Adult Stem Cells Maintain a Constant Phenotype Profile Irrespective of Their Origin, Basal Media, and Long Term Cultures

    Directory of Open Access Journals (Sweden)

    Indumathi Somasundaram

    2015-01-01

    Full Text Available The study aims to identify the phenotypic marker expressions of different human adult stem cells derived from, namely, bone marrow, subcutaneous fat, and omentum fat, cultured in different media, namely, DMEM-Low Glucose, Alpha-MEM, DMEM-F12 and DMEM-KO and under long term culture conditions (>P20. We characterized immunophenotype by using various hematopoietic, mesenchymal, endothelial markers, and cell adhesion molecules in the long term cultures (Passages-P1, P3, P5, P9, P12, P15, and P20. Interestingly, data revealed similar marker expression profiles irrespective of source, basal media, and extensive culturing. This demonstrates that all adult stem cell sources mentioned in this study share similar phenotypic marker and all media seem appropriate for culturing these sources. However, a disparity was observed in the markers such as CD49d, CD54, CD117, CD29, and CD106, thereby warranting further research on these markers. Besides the aforesaid objective, it is understood from the study that immunophenotyping acts as a valuable tool to identify inherent property of each cell, thereby leading to a valuable cell based therapy.

  1. Enhanced genetic modification of adult growth factor mobilized peripheral blood hematopoietic stem and progenitor cells with rapamycin.

    Science.gov (United States)

    Li, Lijing; Torres-Coronado, Mónica; Gu, Angel; Rao, Anitha; Gardner, Agnes M; Epps, Elizabeth W; Gonzalez, Nancy; Tran, Chy-Anh; Wu, Xiwei; Wang, Jin-Hui; DiGiusto, David L

    2014-10-01

    Genetic modification of adult human hematopoietic stem and progenitor cells (HSPCs) with lentiviral vectors leads to long-term gene expression in the progeny of the HSPCs and has been used to successfully treat several monogenic diseases. In some cases, the gene-modified cells have a selective growth advantage over nonmodified cells and eventually are the dominant engrafted population. However, in disease indications for which the gene-modified cells do not have a selective advantage, optimizing transduction of HSPC is paramount to successful stem cell-based gene therapy. We demonstrate here that transduction of adult CD34+ HSPCs with lentiviral vectors in the presence of rapamycin, a widely used mTORC1 inhibitor, results in an approximately threefold increase in stable gene marking with minimal effects on HSPC growth and differentiation. Using this approach, we have demonstrated that we can enhance the frequency of gene-modified HSPCs that give rise to clonogenic progeny in vitro without excessive increases in the number of vector copies per cell or changes in integration pattern. The genetic marking of HSPCs and expression of transgenes is durable, and transplantation of gene-modified HSPCs into immunodeficient mice results in high levels of gene marking of the lymphoid and myeloid progeny in vivo. The prior safe clinical history of rapamycin in other applications supports the use of this compound to generate gene-modified autologous HSPCs for our HIV gene therapy clinical trials. ©AlphaMed Press.

  2. The Meaning of Disease and Spiritual Responses to Stressors in Adults With Acute Leukemia Undergoing Hematopoietic Stem Cell Transplantation.

    Science.gov (United States)

    Farsi, Zahra

    2015-12-01

    Some studies have shown that patients with cancer may experience significant spiritual distress as well as spiritual growth, that there is a positive association between spirituality and coping, and that positive religious coping predicts enhanced health outcomes. This study was designed to help explain how the meaning of disease and spiritual responses to threatening stressors influence the final experiential outcomes of adults with leukemia undergoing hematopoietic stem cell transplantation in Iran. This grounded theory study conducted in-depth interviews between 2009 and 2011 on 10 adults in Iran with leukemia undergoing hematopoietic stem cell transplantation. Recorded audio interviews were transcribed verbatim in Persian and coded and analyzed using Corbin and Strauss (2008)'s approach. Main categories that emerged from data included "experiencing the meaning of cancer"; "changing perceptions of death, life and health"; and "moving toward perfection and sublimity." "Finding meaning" was the main concept that defined the final outcome of the experience of participants. Understanding the meaning to patients of disease and treatments may help healthcare providers better appreciate the patients' perspective and improve the physician-patient relationship. Nurses are well positioned to play a decisive role in helping patients cope effectively with their treatment process and in helping ensure positive outcomes for treatments through their helping patients find the unique meaning of their experience.

  3. Lr67/Yr46 confers adult plant resistance to stem rust and powdery mildew in wheat.

    Science.gov (United States)

    Herrera-Foessel, Sybil A; Singh, Ravi P; Lillemo, Morten; Huerta-Espino, Julio; Bhavani, Sridhar; Singh, Sukhwinder; Lan, Caixia; Calvo-Salazar, Violeta; Lagudah, Evans S

    2014-04-01

    We demonstrate that Lr67/Yr46 has pleiotropic effect on stem rust and powdery mildew resistance and is associated with leaf tip necrosis. Genes are designated as Sr55, Pm46 and Ltn3 , respectively. Wheat (Triticum aestivum) accession RL6077, known to carry the pleiotropic slow rusting leaf and yellow rust resistance genes Lr67/Yr46 in Thatcher background, displayed significantly lower stem rust (P. graminis tritici; Pgt) and powdery mildew (Blumeria graminis tritici; Bgt) severities in Kenya and in Norway, respectively, compared to its recurrent parent Thatcher. We investigated the resistance of RL6077 to stem rust and powdery mildew using Avocet × RL6077 F6 recombinant inbred lines (RILs) derived from two photoperiod-insensitive F3 families segregating for Lr67/Yr46. Greenhouse seedling tests were conducted with Mexican Pgt race RTR. Field evaluations were conducted under artificially initiated stem rust epidemics with Pgt races RTR and TTKST (Ug99 + Sr24) at Ciudad Obregon (Mexico) and Njoro (Kenya) during 2010-2011; and under natural powdery mildew epiphytotic in Norway at Ås and Hamar during 2011 and 2012. In Mexico, a mean reduction of 41 % on stem rust severity was obtained for RILs carrying Lr67/Yr46, compared to RILs that lacked the gene, whereas in Kenya the difference was smaller (16 %) but significant. In Norway, leaf tip necrosis was associated with Lr67/Yr46 and RILs carrying Lr67/Yr46 showed a 20 % reduction in mean powdery mildew severity at both sites across the 2 years of evaluation. Our study demonstrates that Lr67/Yr46 confers partial resistance to stem rust and powdery mildew and is associated with leaf tip necrosis. The corresponding pleiotropic, or tightly linked, genes, designated as Sr55, Pm46, and Ltn3, can be utilized to provide broad-spectrum durable disease resistance in wheat.

  4. Development of intraepithelial T lymphocytes in the intestine of irradiated SCID mice by adult liver hematopoietic stem cells from normal mice

    International Nuclear Information System (INIS)

    Yamagiwa, Satoshi; Seki, Shuhji; Shirai, Katsuaki; Yoshida, Yuhei; Miyaji, Chikako; Watanabe, Hisami; Abo, Toru

    1999-01-01

    Background/Aims: We recently reported the adult mouse liver to contain c-kit + stem cells that can give rise to multilineage leukocytes. This study was designed to determine whether or not adult mouse liver stem cells can generate intraepithelial T cells in the intestine as well as to examine the possibility that adult liver c-kit + stem cells originate from the fetal liver. Methods: Adult liver mononuclear cells, bone marrow (BM) cells, liver c-kit + cells or bone BM c-kit + cells of BALB/c mice were i.v. transferred into 4 Gy irradiated CB17/-SCID mice. In other experiments, fetal liver cells from Ly5.1 C57BL/6 mice and T cell depleted adult BM cells from Ly5.2 C57BL/6 mice were simultaneously transferred into irradiated C57BL/6 SCID mice (Ly5.2). At 1 to 8 weeks after cell transfer, the SCID mice were examined. Results: Not only BM cells and BM c-kit + cells but also liver mononuclear cells and liver c-kit + cells reconstituted γδT cells, CD4 + CD8 + double-positive T cells and CDiα + β - T cells of intestinal intraepithelial lymphocytes of SCID mice. Injection of a mixture of fetal liver cells from Ly5.1 C57BL/6 mice and adult BM cells from Ly5.2 C57BL/6 mice into Ly5.2 C57BL/6 SCID mice induced both Ly5.1 and Ly5.2 T cells, while also generating c-kit + cells of both Ly5.1 and Ly5.2 origins in the liver. Conclusions: Adult mouse liver stem cells were able to generate intestinal intraepithelial T cells of the SCID mice, and it is thus suggested that some adult liver stem cells may indeed be derived from the fetal liver. (au)

  5. Spatio-temporal neural stem cell behavior that leads to both perfect and imperfect structural brain regeneration in adult newts.

    Science.gov (United States)

    Urata, Yuko; Yamashita, Wataru; Inoue, Takeshi; Agata, Kiyokazu

    2018-06-14

    Adult newts can regenerate large parts of their brain from adult neural stem cells (NSCs), but how adult NSCs reorganize brain structures during regeneration remains unclear. In development, elaborate brain structures are produced under broadly coordinated regulations of embryonic NSCs in the neural tube, whereas brain regeneration entails exquisite control of the reestablishment of certain brain parts, suggesting a yet-unknown mechanism directs NSCs upon partial brain excision. Here we report that upon one-quarter excision of the adult newt ( Pleurodeles waltl ) mesencephalon, active participation of local NSCs around specific brain subregions' boundaries leads to some imperfect and some perfect brain regeneration along an individual's rostrocaudal axis. Regeneration phenotypes depend on how the wound closing occurs using local NSCs, and perfect regeneration replicates development-like processes but takes more than one year. Our findings indicate that newt brain regeneration is supported by modularity of boundary-domain NSCs with self-organizing ability in neighboring fields. © 2018. Published by The Company of Biologists Ltd.

  6. SRY-box-containing gene 2 regulation of nuclear receptor tailless (Tlx) transcription in adult neural stem cells.

    Science.gov (United States)

    Shimozaki, Koji; Zhang, Chun-Li; Suh, Hoonkyo; Denli, Ahmet M; Evans, Ronald M; Gage, Fred H

    2012-02-17

    Adult neurogenesis is maintained by self-renewable neural stem cells (NSCs). Their activity is regulated by multiple signaling pathways and key transcription factors. However, it has been unclear whether these factors interplay with each other at the molecular level. Here we show that SRY-box-containing gene 2 (Sox2) and nuclear receptor tailless (TLX) form a molecular network in adult NSCs. We observed that both Sox2 and TLX proteins bind to the upstream region of Tlx gene. Sox2 positively regulates Tlx expression, whereas the binding of TLX to its own promoter suppresses its transcriptional activity in luciferase reporter assays. Such TLX-mediated suppression can be antagonized by overexpressing wild-type Sox2 but not a mutant lacking the transcriptional activation domain. Furthermore, through regions involved in DNA-binding activity, Sox2 and TLX physically interact to form a complex on DNAs that contain a consensus binding site for TLX. Finally, depletion of Sox2 revealed the potential negative feedback loop of TLX expression that is antagonized by Sox2 in adult NSCs. These data suggest that Sox2 plays an important role in Tlx transcription in cultured adult NSCs.

  7. SRY-box-containing Gene 2 Regulation of Nuclear Receptor Tailless (Tlx) Transcription in Adult Neural Stem Cells*

    Science.gov (United States)

    Shimozaki, Koji; Zhang, Chun-Li; Suh, Hoonkyo; Denli, Ahmet M.; Evans, Ronald M.; Gage, Fred H.

    2012-01-01

    Adult neurogenesis is maintained by self-renewable neural stem cells (NSCs). Their activity is regulated by multiple signaling pathways and key transcription factors. However, it has been unclear whether these factors interplay with each other at the molecular level. Here we show that SRY-box-containing gene 2 (Sox2) and nuclear receptor tailless (TLX) form a molecular network in adult NSCs. We observed that both Sox2 and TLX proteins bind to the upstream region of Tlx gene. Sox2 positively regulates Tlx expression, whereas the binding of TLX to its own promoter suppresses its transcriptional activity in luciferase reporter assays. Such TLX-mediated suppression can be antagonized by overexpressing wild-type Sox2 but not a mutant lacking the transcriptional activation domain. Furthermore, through regions involved in DNA-binding activity, Sox2 and TLX physically interact to form a complex on DNAs that contain a consensus binding site for TLX. Finally, depletion of Sox2 revealed the potential negative feedback loop of TLX expression that is antagonized by Sox2 in adult NSCs. These data suggest that Sox2 plays an important role in Tlx transcription in cultured adult NSCs. PMID:22194602

  8. Tuning differentiation signals for efficient propagation and in vitro validation of rat embryonic stem cell cultures.

    Science.gov (United States)

    Meek, Stephen; Sutherland, Linda; Burdon, Tom

    2015-01-01

    The rat is one of the most commonly used laboratory animals in biomedical research and the recent isolation of genuine pluripotent rat embryonic stem (ES) cell lines has provided new opportunities for applying contemporary genetic engineering techniques to the rat and enhancing the use of this rodent in scientific research. Technical refinements that improve the stability of the rat ES cell cultures will undoubtedly further strengthen and broaden the use of these stem cells in biomedical research. Here, we describe a relatively simple and robust protocol that supports the propagation of germ line competent rat ES cells, and outline how tuning stem cell signaling using small molecule inhibitors can be used to both stabilize self-renewal of rat ES cell cultures and aid evaluation of their differentiation potential in vitro.

  9. Potency of Stem Cells

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Potency of Stem Cells. Totipotent Stem Cells (Zygote + first 2 divisions). -Can form placenta, embryo, and any cell of the body. Pluripotent (Embryonic Stem Cells). -Can form any cell of the body but can not form placenta, hence no embryo. Multipotent (Adult stem cells).

  10. Phenotypic and functional analyses show stem cell-derived hepatocyte-like cells better mimic fetal rather than adult hepatocytes.

    Science.gov (United States)

    Baxter, Melissa; Withey, Sarah; Harrison, Sean; Segeritz, Charis-Patricia; Zhang, Fang; Atkinson-Dell, Rebecca; Rowe, Cliff; Gerrard, Dave T; Sison-Young, Rowena; Jenkins, Roz; Henry, Joanne; Berry, Andrew A; Mohamet, Lisa; Best, Marie; Fenwick, Stephen W; Malik, Hassan; Kitteringham, Neil R; Goldring, Chris E; Piper Hanley, Karen; Vallier, Ludovic; Hanley, Neil A

    2015-03-01

    Hepatocyte-like cells (HLCs), differentiated from pluripotent stem cells by the use of soluble factors, can model human liver function and toxicity. However, at present HLC maturity and whether any deficit represents a true fetal state or aberrant differentiation is unclear and compounded by comparison to potentially deteriorated adult hepatocytes. Therefore, we generated HLCs from multiple lineages, using two different protocols, for direct comparison with fresh fetal and adult hepatocytes. Protocols were developed for robust differentiation. Multiple transcript, protein and functional analyses compared HLCs to fresh human fetal and adult hepatocytes. HLCs were comparable to those of other laboratories by multiple parameters. Transcriptional changes during differentiation mimicked human embryogenesis and showed more similarity to pericentral than periportal hepatocytes. Unbiased proteomics demonstrated greater proximity to liver than 30 other human organs or tissues. However, by comparison to fresh material, HLC maturity was proven by transcript, protein and function to be fetal-like and short of the adult phenotype. The expression of 81% phase 1 enzymes in HLCs was significantly upregulated and half were statistically not different from fetal hepatocytes. HLCs secreted albumin and metabolized testosterone (CYP3A) and dextrorphan (CYP2D6) like fetal hepatocytes. In seven bespoke tests, devised by principal components analysis to distinguish fetal from adult hepatocytes, HLCs from two different source laboratories consistently demonstrated fetal characteristics. HLCs from different sources are broadly comparable with unbiased proteomic evidence for faithful differentiation down the liver lineage. This current phenotype mimics human fetal rather than adult hepatocytes. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  11. Sources of adult mesenchymal stem cells for ligament and tendon tissue engineering.

    Science.gov (United States)

    Dhinsa, Baljinder S; Mahapatra, Anant N; Khan, Wasim S

    2015-01-01

    Tendon and ligament injuries are common, and repair slowly with reduced biomechanical properties. With increasing financial demands on the health service and patients to recover from tendon and ligament injuries faster, and with less morbidity, health professionals are exploring new treatment options. Tissue engineering may provide the answer, with its unlimited source of natural cells that in the correct environment may improve repair and regeneration of tendon and ligament tissue. Mesenchymal stem cells have demonstrated the ability to self renew and have multilineage differentiation potential. The use of bone marrow-derived mesenchymal stem cells has been reported, however significant in vitro culture expansion is required due to the low yield of cells, which has financial implications. Harvesting of bone marrow cells also has associated morbidity. Several studies have looked at alternative sources for mesenchymal stem cells. Reports in literature from animal studies have been encouraging, however further work is required. This review assesses the potential sources of mesenchymal stem cells for tissue engineering in tendons and ligaments.

  12. The adult Drosophila malphigian tubules are maintained by multipotent stem cells | Center for Cancer Research

    Science.gov (United States)

    All animals must excrete the waste products of metabolism. Excretion is performed by the kidney in vertebrates and by the Malpighian tubules in Drosophila. The mammalian kidney has an inherent ability for recovery and regeneration after ischemic injury. Stem cells and progenitor cells have been proposed to be responsible for repair and regeneration of injured renal tissue.

  13. Sirt1 Protects Stressed Adult Hematopoietic Stem Cells | Center for Cancer Research

    Science.gov (United States)

    The immune system relies on a stable pool of hematopoietic stem and progenitor cells (HSPCs) to respond properly to injury or stress. Maintaining genomic integrity and appropriate gene expression is essential for HSPC homeostasis, and dysregulation can result in myeloproliferative disorders or loss of immune function. Sirt1 is a histone deacetylase that can protect embryonic

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

    International Nuclear Information System (INIS)

    Kishi, Teruki; Takao, Tukasa; Fujita, Kiyohide; Taniguchi, Hideki

    2006-01-01

    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

  15. Unrelated allogeneic stem-cell transplantation in adult patients – 10-year experience

    Directory of Open Access Journals (Sweden)

    Jožef Pretnar

    2012-12-01

    Conclusion: Unrelated allogeneic stem-cell transplantation is suitable for acute myeloblastic leukemias with unfavorable risk factors. However, results in acute lymphoblastic leukemia are worse. Unrelated transplantation is not efficient as salvage treatment for patients with recurrent disease after autologous transplantation or chemotherapy- resistant relapse.

  16. Mechanisms of DNA damage repair in adult stem cells and implications for cancer formation.

    Science.gov (United States)

    Weeden, Clare E; Asselin-Labat, Marie-Liesse

    2018-01-01

    Maintenance of genomic integrity in tissue-specific stem cells is critical for tissue homeostasis and the prevention of deleterious diseases such as cancer. Stem cells are subject to DNA damage induced by endogenous replication mishaps or exposure to exogenous agents. The type of DNA lesion and the cell cycle stage will invoke different DNA repair mechanisms depending on the intrinsic DNA repair machinery of a cell. Inappropriate DNA repair in stem cells can lead to cell death, or to the formation and accumulation of genetic alterations that can be transmitted to daughter cells and so is linked to cancer formation. DNA mutational signatures that are associated with DNA repair deficiencies or exposure to carcinogenic agents have been described in cancer. Here we review the most recent findings on DNA repair pathways activated in epithelial tissue stem and progenitor cells and their implications for cancer mutational signatures. We discuss how deep knowledge of early molecular events leading to carcinogenesis provides insights into DNA repair mechanisms operating in tumours and how these could be exploited therapeutically. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Transcranial magnetic stimulation of human adult stem cells in the mammalian brain

    Directory of Open Access Journals (Sweden)

    Karlea L Kremer

    2016-03-01

    Full Text Available Introduction: The burden of stroke on the community is growing, and therefore, so is the need for a therapy to overcome the disability following stroke. Cellular-based therapies are being actively investigated at a pre-clinical and clinical level. Studies have reported the beneficial effects of exogenous stem cell implantation, however, these benefits are also associated with limited survival of implanted stem cells. This exploratory study investigated the use of transcranial magnetic stimulation (TMS as a complementary therapy to increase stem cell survival following implantation of human dental pulp stem cells (DPSC in the rodent cortex. Methods: Sprague-Dawley rats were anaesthetised and injected with 6x105 DPSC or control media via an intracranial injection, and then received real TMS (TMS0.2Hz or sham TMS (TMSsham every 2nd day beginning on day 3 post DPSC injection for 2 weeks. Brain sections were analysed for the survival, migration and differentiation characteristics of the implanted cells. Results: In animals treated with DPSC and TMS0.2Hz there were significantly less implanted DPSC and those that survived remained in the original cerebral hemisphere compared to animals that received TMSsham. The surviving implanted DPSC in TMS0.2Hz were also found to express the apoptotic marker Caspase-3. Conclusions: We suggest that TMS at this intensity may cause an increase in glutamate levels, which promotes an unfavourable environment for stem cell implantation, proliferation and differentiation. It should be noted that only one paradigm of TMS was tested as this was conducted as an exploratory study, and further TMS paradigms should be investigated in the future.

  18. Lineage analysis of quiescent regenerative stem cells in the adult brain by genetic labelling reveals spatially restricted neurogenic niches in the olfactory bulb.

    Science.gov (United States)

    Giachino, Claudio; Taylor, Verdon

    2009-07-01

    The subventricular zone (SVZ) of the lateral ventricles is the major neurogenic region in the adult mammalian brain, harbouring neural stem cells within defined niches. The identity of these stem cells and the factors regulating their fate are poorly understood. We have genetically mapped a population of Nestin-expressing cells during postnatal development to study their potential and fate in vivo. Taking advantage of the recombination characteristics of a nestin::CreER(T2) allele, we followed a subpopulation of neural stem cells and traced their fate in a largely unrecombined neurogenic niche. Perinatal nestin::CreER(T2)-expressing cells give rise to multiple glial cell types and neurons, as well as to stem cells of the adult SVZ. In the adult SVZ nestin::CreER(T2)-expressing neural stem cells give rise to several neuronal subtypes in the olfactory bulb (OB). We addressed whether the same population of neural stem cells play a role in SVZ regeneration. Following anti-mitotic treatment to eliminate rapidly dividing progenitors, relatively quiescent nestin::CreER(T2)-targeted cells are spared and contribute to SVZ regeneration, generating new proliferating precursors and neuroblasts. Finally, we have identified neurogenic progenitors clustered in ependymal-like niches within the rostral migratory stream (RMS) of the OB. These OB-RMS progenitors generate neuroblasts that, upon transplantation, graft, migrate and differentiate into granule and glomerular neurons. In summary, using conditional lineage tracing we have identified neonatal cells that are the source of neurogenic and regenerative neural stem cells in the adult SVZ and occupy a novel neurogenic niche in the OB.

  19. Adult-Brain-Derived Neural Stem Cells Grafting into a Vein Bridge Increases Postlesional Recovery and Regeneration in a Peripheral Nerve of Adult Pig

    Directory of Open Access Journals (Sweden)

    Olivier Liard

    2012-01-01

    Full Text Available We attempted transplantation of adult neural stem cells (ANSCs inside an autologous venous graft following surgical transsection of nervis cruralis with 30 mm long gap in adult pig. The transplanted cell suspension was a primary culture of neurospheres from adult pig subventricular zone (SVZ which had been labeled in vitro with BrdU or lentivirally transferred fluorescent protein. Lesion-induced loss of leg extension on the thigh became definitive in controls but was reversed by 45–90 days after neurosphere-filled vein grafting. Electromyography showed stimulodetection recovery in neurosphere-transplanted pigs but not in controls. Postmortem immunohistochemistry revealed neurosphere-derived cells that survived inside the venous graft from 10 to 240 post-lesion days and all displayed a neuronal phenotype. Newly formed neurons were distributed inside the venous graft along the severed nerve longitudinal axis. Moreover, ANSC transplantation increased CNPase expression, indicating activation of intrinsic Schwann cells. Thus ANSC transplantation inside an autologous venous graft provides an efficient repair strategy.

  20. Adult DRG Stem/Progenitor Cells Generate Pericytes in the Presence of Central Nervous System (CNS) Developmental Cues, and Schwann Cells in Response to CNS Demyelination.

    Science.gov (United States)

    Vidal, Marie; Maniglier, Madlyne; Deboux, Cyrille; Bachelin, Corinne; Zujovic, Violetta; Baron-Van Evercooren, Anne

    2015-06-01

    It has been proposed that the adult dorsal root ganglia (DRG) harbor neural stem/progenitor cells (NPCs) derived from the neural crest. However, the thorough characterization of their stemness and differentiation plasticity was not addressed. In this study, we investigated adult DRG-NPC stem cell properties overtime, and their fate when ectopically grafted in the central nervous system. We compared them in vitro and in vivo to the well-characterized adult spinal cord-NPCs derived from the same donors. Using micro-dissection and neurosphere cultures, we demonstrate that adult DRG-NPCs have quasi unlimited self-expansion capacities without compromising their tissue specific molecular signature. Moreover, they differentiate into multiple peripheral lineages in vitro. After transplantation, adult DRG-NPCs generate pericytes in the developing forebrain but remyelinating Schwann cells in response to spinal cord demyelination. In addition, we show that axonal and endothelial/astrocytic factors as well astrocytes regulate the fate of adult DRG-NPCs in culture. Although the adult DRG-NPC multipotency is restricted to the neural crest lineage, their dual responsiveness to developmental and lesion cues highlights their impressive adaptive and repair potentials making them valuable targets for regenerative medicine. © 2015 AlphaMed Press.

  1. Sphingosine-1-phosphate mediates proliferation maintaining the multipotency of human adult bone marrow and adipose tissue-derived stem cells.

    Science.gov (United States)

    He, Xiaoli; H'ng, Shiau-Chen; Leong, David T; Hutmacher, Dietmar W; Melendez, Alirio J

    2010-08-01

    High renewal and maintenance of multipotency of human adult stem cells (hSCs), are a prerequisite for experimental analysis as well as for potential clinical usages. The most widely used strategy for hSC culture and proliferation is using serum. However, serum is poorly defined and has a considerable degree of inter-batch variation, which makes it difficult for large-scale mesenchymal stem cells (MSCs) expansion in homogeneous culture conditions. Moreover, it is often observed that cells grown in serum-containing media spontaneously differentiate into unknown and/or undesired phenotypes. Another way of maintaining hSC development is using cytokines and/or tissue-specific growth factors; this is a very expensive approach and can lead to early unwanted differentiation. In order to circumvent these issues, we investigated the role of sphingosine-1-phosphate (S1P), in the growth and multipotency maintenance of human bone marrow and adipose tissue-derived MSCs. We show that S1P induces growth, and in combination with reduced serum, or with the growth factors FGF and platelet-derived growth factor-AB, S1P has an enhancing effect on growth. We also show that the MSCs cultured in S1P-supplemented media are able to maintain their differentiation potential for at least as long as that for cells grown in the usual serum-containing media. This is shown by the ability of cells grown in S1P-containing media to be able to undergo osteogenic as well as adipogenic differentiation. This is of interest, since S1P is a relatively inexpensive natural product, which can be obtained in homogeneous high-purity batches: this will minimize costs and potentially reduce the unwanted side effects observed with serum. Taken together, S1P is able to induce proliferation while maintaining the multipotency of different human stem cells, suggesting a potential for S1P in developing serum-free or serum-reduced defined medium for adult stem cell cultures.

  2. Nanoscale definition of substrate materials to direct human adult stem cells towards tissue specific populations.

    Science.gov (United States)

    Curran, Judith M; Chen, Rui; Stokes, Robert; Irvine, Eleanor; Graham, Duncan; Gubbins, Earl; Delaney, Deany; Amro, Nabil; Sanedrin, Raymond; Jamil, Haris; Hunt, John A

    2010-03-01

    The development of homogenously nano-patterned chemically modified surfaces that can be used to initiate a cellular response, particularly stem cell differentiation, in a highly controlled manner without the need for exogenous biological factors has never been reported, due to that fact that precisely defined and reproducible systems have not been available that can be used to study cell/material interactions and unlock the potential of a material driven cell response. Until now material driven stem cell (furthermore any cell) responses have been variable due to the limitations in definition and reproducibility of the underlying substrate and the lack of true homogeneity of modifications that can dictate a cellular response at a sub-micron level that can effectively control initial cell interactions of all cells that contact the surface. Here we report the successful design and use of homogenously molecularly nanopatterned surfaces to control initial stem cell adhesion and hence function. The highly specified nano-patterned arrays were compared directly to silane modified bulk coated substrates that have previously been proven to initiate mesenchymal stem cell (MSC) differentiation in a heterogenous manner, the aim of this study was to prove the efficiency of these previously observed cell responses could be enhanced by the incorporation of nano-patterns. Nano-patterned surfaces were prepared by Dip Pen Nanolithography (DPN) to produce arrays of 70 nm sized dots separated by defined spacings of 140, 280 and 1000 nm with terminal functionalities of carboxyl, amino, methyl and hydroxyl and used to control cell growth. These nanopatterned surfaces exhibited unprecedented control of initial cell interactions and will change the capabilities for stem cell definition in vitro and then cell based medical therapies. In addition to highlighting the ability of the materials to control stem cell functionality on an unprecedented scale this research also introduces the

  3. Stem Cell Information: Glossary

    Science.gov (United States)

    ... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... here Home » Glossary Back to top Glossary Adult stem cell Astrocyte Blastocoel Blastocyst Bone marrow stromal cells Bone ...

  4. Lichen striatus occurring after allogenic peripheral blood stem cell transplantation in an adult with aplastic anemia.

    Science.gov (United States)

    Mun, Je-Ho; Park, Hyun-Je; Kim, Hoon-Soo; Kim, Su-Han; Ko, Hyun-Chang; Kim, Byung-Soo; Kim, Moon-Bum

    2012-02-01

    Lichens striatus (LS) is an acquired, self-limiting inflammatory dermatosis that follows the lines of Blaschko. The etiology of the eruption is unknown, but several theories have been proposed with focus on environmental factors, viral infection, cutaneous injury, hypersensitivity, and genetic predisposition. We describe a 19-year-old woman who developed a unilateral linear eruption 17 months after allogenic peripheral blood stem cell transplantation. Histopathology revealed features, which were consistent with LS. To the best of our knowledge, our patient is the first case describing the appearance of LS occurring after allogenic stem cell transplantation. We speculate that this condition represents an unusual form of localized, chronic graft-versus-host disease.

  5. Adult Stem Cell-Based Enhancement of Nerve Conduit for Peripheral Nerve Repair

    Science.gov (United States)

    2017-10-01

    neurotrophically activated cell types and conditioned media (via RT-PCR and ELISA of neurotrophic factors), followed by cell storage Specific objective 9...Mesenchymal Progenitor Cells (NI-MiMPCs) and Mesenchymal Stem Cells (MSCs), quantified via ELISA . MiMPCs and MSCs were cultured in neurotrophic induction...LIF, (E) osteonectin, and (F) clusterin. All ELISA results are expressed in pg/ml or ng/ml produced per million cells. Medium taken from NI-MiMPC

  6. Lichen Striatus Occurring after Allogenic Peripheral Blood Stem Cell Transplantation in an Adult with Aplastic Anemia

    OpenAIRE

    Mun, Je-Ho; Park, Hyun-Je; Kim, Hoon-Soo; Kim, Su-Han; Ko, Hyun-Chang; Kim, Byung-Soo; Kim, Moon-Bum

    2012-01-01

    Lichens striatus (LS) is an acquired, self-limiting inflammatory dermatosis that follows the lines of Blaschko. The etiology of the eruption is unknown, but several theories have been proposed with focus on environmental factors, viral infection, cutaneous injury, hypersensitivity, and genetic predisposition. We describe a 19-year-old woman who developed a unilateral linear eruption 17 months after allogenic peripheral blood stem cell transplantation. Histopathology revealed features, which w...

  7. Adult Stem Cell Based Enhancement of Nerve Conduit for Peripheral Nerve Repair

    Science.gov (United States)

    2016-10-01

    accompanied by injuries to peripheral nerves; if not repaired, the trauma can lead to significant dysfunction and disability . While nerves have the ability to...recovery, minimized disability , and increased quality of life for our wounded warriors. 2. KEYWORDS: Stem Cell, Nerve Conduit, Peripheral Nerve...would be a paradigm shift away from ordering X-rays at 10-12 weeks and only ordering a CT scan. It has the potential to change the standard of care

  8. Role of the immune system in regeneration and its dynamic interplay with adult stem cells.

    Science.gov (United States)

    Abnave, Prasad; Ghigo, Eric

    2018-04-09

    The immune system plays an indispensable role in the process of tissue regeneration following damage as well as during homeostasis. Inflammation and immune cell recruitment are signs of early onset injury. At the wound site, immune cells not only help to clear debris but also secrete numerous signalling molecules that induce appropriate cell proliferation and differentiation programmes essential for successful regeneration. However, the immune system does not always perform a complementary role in regeneration and several reports have suggested that increased inflammation can inhibit the regeneration process. Successful regeneration requires a balanced immune cell response, with the recruitment of accurately polarised immune cells in an appropriate quantity. The regulatory interactions of the immune system with regeneration are not unidirectional. Stem cells, as key players in regeneration, can also modulate the immune system in several ways to facilitate regeneration. In this review, we will focus on recent research demonstrating the key role of immune system in the regeneration process as well as the immunomodulatory effects of stem cells. Finally, we propose that research investigating the interplay between the immune system and stem cells within highly regenerating animals can benefit the identification of the key interactions and molecules required for successful regeneration. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Cellular modulation of polymeric device surfaces: promise of adult stem cells for neuroprosthetics

    Directory of Open Access Journals (Sweden)

    Anja eRichter

    2011-10-01

    Full Text Available Minimizing the foreign body response is seen as one critical research strategy for implants especially when designed for immune-privileged organs like the brain. The context of this work is to improve deep brain stimulating devices used in a consistently growing spectrum of psychomotoric and psychiatric diseases mainly in form of stiff electrodes. Based on the compliance match hypothesis of biocompatibility we present another step forward using flexible implant materials covered with brain-mimicking layers. Therefore we covered two types of flexible polyimide films with glandular stem cells derived from pancreatic acini. Using Real Time-PCR and fluorescent immunocytochemistry we analyzed markers representing various cell types of all three germ layers and stemness. The results demonstrate on mRNA and protein level the unchanged differentiation potential of the cells on the polyimides. We additionally developed a fibrinous hydrogel coating to protect them against shear forces upon eventual implantation. By repeating previous analysis and additional metabolism tests for all stages we corroborate the validity of this improvement. Consequently we assume that a stem cell cover may provide a native, fully and actively integrating brain-mimicking interface to the neuropil.

  10. Geminin Participates in Differentiation Decisions of Adult Neural Stem Cells Transplanted in the Hemiparkinsonian Mouse Brain.

    Science.gov (United States)

    Taouki, Ioanna; Tasiudi, Eve; Lalioti, Maria-Eleni; Kyrousi, Christina; Skavatsou, Eleni; Kaplani, Konstantina; Lygerou, Zoi; Kouvelas, Elias D; Mitsacos, Adamantia; Giompres, Panagiotis; Taraviras, Stavros

    2017-08-15

    Neural stem cells have been considered as a source of stem cells that can be used for cell replacement therapies in neurodegenerative diseases, as they can be isolated and expanded in vitro and can be used for autologous grafting. However, due to low percentages of survival and varying patterns of differentiation, strategies that will enhance the efficacy of transplantation are under scrutiny. In this article, we have examined whether alterations in Geminin's expression, a protein that coordinates the balance between self-renewal and differentiation, can improve the properties of stem cells transplanted in 6-OHDA hemiparkinsonian mouse model. Our results indicate that, in the absence of Geminin, grafted cells differentiating into dopaminergic neurons were decreased, while an increased number of oligodendrocytes were detected. The number of proliferating multipotent cells was not modified by the absence of Geminin. These findings encourage research related to the impact of Geminin on transplantations for neurodegenerative disorders, as an important molecule in influencing differentiation decisions of the cells composing the graft.

  11. Cytoarchitecture and ultrastructure of neural stem cell niches and neurogenic complexes maintaining adult neurogenesis in the olfactory midbrain of spiny lobsters, Panulirus argus.

    Science.gov (United States)

    Schmidt, Manfred; Derby, Charles D

    2011-08-15

    New interneurons are continuously generated in small proliferation zones within neuronal somata clusters in the olfactory deutocerebrum of adult decapod crustaceans. Each proliferation zone is connected to a clump of cells containing one neural stem cell (i.e., adult neuroblast), thus forming a "neurogenic complex." Here we provide a detailed analysis of the cytoarchitecture of neurogenic complexes in adult spiny lobsters, Panulirus argus, based on transmission electron microscopy and labeling with cell-type-selective markers. The clump of cells is composed of unique bipolar clump-forming cells that collectively completely envelop the adult neuroblast and are themselves ensheathed by a layer of processes of multipolar cell body glia. An arteriole is attached to the clump of cells, but dye perfusion experiments show that hemolymph has no access to the interior of the clump of cells. Thus, the clump of cells fulfills morphological criteria of a protective stem cell niche, with clump-forming cells constituting the adult neuroblast's microenvironment together with the cell body glia processes separating it from other tissue components. Bromodeoxyuridine pulse-chase experiments with short survival times suggest that adult neuroblasts are not quiescent but rather cycle actively during daytime. We propose a cell lineage model in which an asymmetrically dividing adult neuroblast repopulates the pool of neuronal progenitor cells in the associated proliferation zone. In conclusion, as in mammalian brains, adult neurogenesis in crustacean brains is fueled by neural stem cells that are maintained by stem cell niches that preserve elements of the embryonic microenvironment and contain glial and vascular elements. Copyright © 2011 Wiley-Liss, Inc.

  12. Effects of FGF-2 on human adipose tissue derived adult stem cells morphology and chondrogenesis enhancement in Transwell culture

    Energy Technology Data Exchange (ETDEWEB)

    Kabiri, Azadeh, E-mail: z_kabiri@resident.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Esfandiari, Ebrahim, E-mail: esfandiari@med.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Hashemibeni, Batool, E-mail: hashemibeni@med.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Kazemi, Mohammad, E-mail: m_kazemi@med.mui.ac.i [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Mardani, Mohammad, E-mail: mardani@med.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Esmaeili, Abolghasem, E-mail: abesmaeili@yahoo.com [Cell, Molecular and Developmental Biology Division, Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan (Iran, Islamic Republic of)

    2012-07-27

    Highlights: Black-Right-Pointing-Pointer We investigated effects of FGF-2 on hADSCs. Black-Right-Pointing-Pointer We examine changes in the level of gene expressions of SOX-9, aggrecan and collagen type II and type X. Black-Right-Pointing-Pointer FGF-2 induces chondrogenesis in hADSCs, which Bullet Increasing information will decrease quality if hospital costs are very different. Black-Right-Pointing-Pointer The result of this study may be beneficial in cartilage tissue engineering. -- Abstract: Injured cartilage is difficult to repair due to its poor vascularisation. Cell based therapies may serve as tools to more effectively regenerate defective cartilage. Both adult mesenchymal stem cells (MSCs) and human adipose derived stem cells (hADSCs) are regarded as potential stem cell sources able to generate functional cartilage for cell transplantation. Growth factors, in particular the TGF-b superfamily, influence many processes during cartilage formation, including cell proliferation, extracellular matrix synthesis, maintenance of the differentiated phenotype, and induction of MSCs towards chondrogenesis. In the current study, we investigated the effects of FGF-2 on hADSC morphology and chondrogenesis in Transwell culture. hADSCs were obtained from patients undergoing elective surgery, and then cultured in expansion medium alone or in the presence of FGF-2 (10 ng/ml). mRNA expression levels of SOX-9, aggrecan and collagen type II and type X were quantified by real-time polymerase chain reaction. The morphology, doubling time, trypsinization time and chondrogenesis of hADSCs were also studied. Expression levels of SOX-9, collagen type II, and aggrecan were all significantly increased in hADSCs expanded in presence of FGF-2. Furthermore FGF-2 induced a slender morphology, whereas doubling time and trypsinization time decreased. Our results suggest that FGF-2 induces hADSCs chondrogenesis in Transwell culture, which may be beneficial in cartilage tissue engineering.

  13. Co-culture of Adult Mesenchymal Stem Cells and Nucleus Pulposus Cells in Bilaminar Pellets for Intervertebral Disc Regeneration.

    Science.gov (United States)

    Allon, Aliza A; Schneider, Richard A; Lotz, Jeffrey C

    2009-01-01

    Our goal is to optimize stem cell-based tissue engineering strategies in the context of the intervertebral disc environment. We explored the benefits of co-culturing nucleus pulposus cells (NPC) and adult mesenchymal stem cells (MSC) using a novel spherical bilaminar pellet culture system where one cell type is enclosed in a sphere of the other cell type. Our 3D system provides a structure that exploits embryonic processes such as tissue induction and condensation. We observed a unique phenomenon: the budding of co-culture pellets and the formation of satellite pellets that separate from the main pellet. MSC and NPC co-culture pellets were formed with three different structural organizations. The first had random organization. The other two had bilaminar organization with either MSC inside and NPC outside or NPC inside and MSC outside. By 14 days, all co-culture pellets exhibited budding and spontaneously generated satellite pellets. The satellite pellets were composed of both cell types and, surprisingly, all had the same bilaminar organization with MSC on the inside and NPC on the outside. This organization was independent of the structure of the main pellet that the satellites stemmed from. The main pellets generated satellite pellets that spontaneously organized into a bilaminar structure. This implies that structural organization occurs naturally in this cell culture system and may be inherently favorable for cell-based tissue engineering strategies. The occurrence of budding and the organization of satellite pellets may have important implications for the use of co-culture pellets in cell-based therapies for disc regeneration. From a therapeutic point of view, the generation of satellite pellets may be a beneficial feature that would serve to spread donor cells throughout the host matrix and restore normal matrix composition in a sustainable way, ultimately renewing tissue function.

  14. Effects of FGF-2 on human adipose tissue derived adult stem cells morphology and chondrogenesis enhancement in Transwell culture

    International Nuclear Information System (INIS)

    Kabiri, Azadeh; Esfandiari, Ebrahim; Hashemibeni, Batool; Kazemi, Mohammad; Mardani, Mohammad; Esmaeili, Abolghasem

    2012-01-01

    Highlights: ► We investigated effects of FGF-2 on hADSCs. ► We examine changes in the level of gene expressions of SOX-9, aggrecan and collagen type II and type X. ► FGF-2 induces chondrogenesis in hADSCs, which •Increasing information will decrease quality if hospital costs are very different. ► The result of this study may be beneficial in cartilage tissue engineering. -- Abstract: Injured cartilage is difficult to repair due to its poor vascularisation. Cell based therapies may serve as tools to more effectively regenerate defective cartilage. Both adult mesenchymal stem cells (MSCs) and human adipose derived stem cells (hADSCs) are regarded as potential stem cell sources able to generate functional cartilage for cell transplantation. Growth factors, in particular the TGF-b superfamily, influence many processes during cartilage formation, including cell proliferation, extracellular matrix synthesis, maintenance of the differentiated phenotype, and induction of MSCs towards chondrogenesis. In the current study, we investigated the effects of FGF-2 on hADSC morphology and chondrogenesis in Transwell culture. hADSCs were obtained from patients undergoing elective surgery, and then cultured in expansion medium alone or in the presence of FGF-2 (10 ng/ml). mRNA expression levels of SOX-9, aggrecan and collagen type II and type X were quantified by real-time polymerase chain reaction. The morphology, doubling time, trypsinization time and chondrogenesis of hADSCs were also studied. Expression levels of SOX-9, collagen type II, and aggrecan were all significantly increased in hADSCs expanded in presence of FGF-2. Furthermore FGF-2 induced a slender morphology, whereas doubling time and trypsinization time decreased. Our results suggest that FGF-2 induces hADSCs chondrogenesis in Transwell culture, which may be beneficial in cartilage tissue engineering.

  15. Exploring the feasibility of a therapeutic music video intervention in adolescents and young adults during stem-cell transplantation.

    Science.gov (United States)

    Burns, Debra S; Robb, Sheri L; Haase, Joan E

    2009-01-01

    The purpose of this study was to explore the feasibility and preliminary efficacy of a therapeutic music video (TMV) intervention for adolescents and young adults (AYAs) undergoing stem-cell transplantation (SCT). Twelve AYAs (aged 11-24 years) were randomized to the TMV or an audio-book protocol. The TMV was designed to diminish symptom distress and improve coping, derived meaning, resilience, and quality of life by supporting AYAs in exploring thoughts and feelings. Six sessions with a board-certified music therapist were held twice a week for 3 weeks. The Adolescent Resilience Model guided the selection of a large, comprehensive battery of outcome measures. Major data collections occurred before admission, after intervention, and at 100 days after transplantation. Participants completed a brief set of measures at presession/postsessions 2, 4, and 6. Rates of consent, session completion, and questionnaire completion supported feasibility. Immediate follow-up measures suggest positive trends in the TMV group for hope, spirituality, confidence/mastery, and self-transcendence. Positive trends at 100 days include MOS, symptoms distress, defensive coping, spirituality, and self-transcendence. Therapeutic music video participants also demonstrated gains in quality of life. The TMV intervention may buffer the immediate after-effects of the stem-cell transplantation experience, and a larger study is warranted.

  16. Hematopoietic stem cells can be separated from leukemic cells in a subgroup of adult acute lymphoblastic leukemia patients.

    Science.gov (United States)

    Wang, Wenwen; Foerner, Elena; Buss, Eike; Jauch, Anna; Eckstein, Volker; Wuchter, Patrick; Ho, Anthony D; Lutz, Christoph

    2017-06-01

    In B-cell acute lymphoblastic leukemia (B-ALL) separation of normal hematopoietic stem cells (HSC) has so far been limited to a subgroup of patients. As aldehyde dehydrogenase (ALDH)-activity is enriched in various stem cells we investigated its value for HSC isolation in adult B-ALL. Based on ALDH-activity patients could be stratified in ALDH-numerous (≥1.9% ALDH +  cells) and ALDH-rare (cells) cases. In ALDH-rare B-ALL clonal-marker negative HSC could be separated by the CD34 + CD38 - ALDH +  phenotype, whereas this separation was not possible in ALDH-numerous B-ALL. Functional analysis confirmed the HSC-potential of isolated cells, which were uniformly CD19-negative. However, addition of ALDH-activity further improved HSC-purity. In summary, we provide a method to separate functionally normal HSC from leukemic cells in a subgroup of B-ALL patients that can be identified prospectively. This protocol thereby facilitates comparative analyses of matched HSC and leukemic cells in order to improve our understanding of leukemia evolution.

  17. Comparison of outcomes after unrelated cord blood and unmanipulated haploidentical stem cell transplantation in adults with acute leukemia

    DEFF Research Database (Denmark)

    Ruggeri, A; Labopin, M; Sanz, G

    2015-01-01

    outcomes after UCBT and Haplo in adults with de novo acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). Median follow-up was 24 months. Analysis was performed separately for patients with AML, n=918 (Haplo=360, UCBT=558) and ALL, n=528 (Haplo=158 and UCBT=370). UCBT was associated......Outcomes after unmanipulated haploidentical stem cell transplantation (Haplo) and after unrelated cord blood transplantation (UCBT) are encouraging and have become alternative options to treat patients with high-risk acute leukemia without human leukocyte antigen (HLA) matched donor. We compared...... with delayed engraftment and higher graft failure in both AML and ALL recipients. In multivariate analysis, UCBT was associated with lower incidence of chronic graft-vs-host disease both in the AML group (hazard ratio (HR)=0.63, P=0.008) and in the ALL group (HR=0.58, P=0.01). Not statistically significant...

  18. Over-expression of hNGF in adult human olfactory bulb neural stem cells promotes cell growth and oligodendrocytic differentiation

    NARCIS (Netherlands)

    H.E.S. Marei (Hany); A. Althani (Asmaa); N. Afifi (Nahla); A. Abd-Elmaksoud (Ahmed); C. Bernardini (Camilla); F. Michetti (Fabrizio); M. Barba (Marta); M. Pescatori (Mario); G. Maira (Giulio); E. Paldino (Emanuela); L. Manni (Luigi); P. Casalbore (Patrizia); C. Cenciarelli (Carlo)

    2013-01-01

    textabstractThe adult human olfactory bulb neural stem/progenitor cells (OBNC/PC) are promising candidate for cell-based therapy for traumatic and neurodegenerative insults. Exogenous application of NGF was suggested as a promising therapeutic strategy for traumatic and neurodegenerative diseases,

  19. Microvesicles derived from adult human bone marrow and tissue specific mesenchymal stem cells shuttle selected pattern of miRNAs.

    Directory of Open Access Journals (Sweden)

    Federica Collino

    cells may, at least in part, depend on MV-shuttled miRNAs. Data generated from this study, stimulate further functional investigations on the predicted target genes and pathways involved in the biological effect of human adult stem cells.

  20. Controlling Adult Stem Cell Behavior Using Nanodiamond-Reinforced Hydrogel: Implication in Bone Regeneration Therapy.

    Science.gov (United States)

    Pacelli, Settimio; Maloney, Ryan; Chakravarti, Aparna R; Whitlow, Jonathan; Basu, Sayantani; Modaresi, Saman; Gehrke, Stevin; Paul, Arghya

    2017-07-26

    Nanodiamonds (NDs) have attracted considerable attention as drug delivery nanocarriers due to their low cytotoxicity and facile surface functionalization. Given these features, NDs have been recently investigated for the fabrication of nanocomposite hydrogels for tissue engineering. Here we report the synthesis of a hydrogel using photocrosslinkable gelatin methacrylamide (GelMA) and NDs as a three-dimensional scaffold for drug delivery and stem cell-guided bone regeneration. We investigated the effect of different concentration of NDs on the physical and mechanical properties of the GelMA hydrogel network. The inclusion of NDs increased the network stiffness, which in turn augmented the traction forces generated by human adipose stem cells (hASCs). We also tested the ability of NDs to adsorb and modulate the release of a model drug dexamethasone (Dex) to promote the osteogenic differentiation of hASCs. The ND-Dex complexes modulated gene expression, cell area, and focal adhesion number in hASCs. Moreover, the integration of the ND-Dex complex within GelMA hydrogels allowed a higher retention of Dex over time, resulting in significantly increased alkaline phosphatase activity and calcium deposition of encapsulated hASCs. These results suggest that conventional GelMA hydrogels can be coupled with conjugated NDs to develop a novel platform for bone tissue engineering.

  1. Pediatric and Adult High-Grade Glioma Stem Cell Culture Models Are Permissive to Lytic Infection with Parvovirus H-1.

    Science.gov (United States)

    Josupeit, Rafael; Bender, Sebastian; Kern, Sonja; Leuchs, Barbara; Hielscher, Thomas; Herold-Mende, Christel; Schlehofer, Jörg R; Dinsart, Christiane; Witt, Olaf; Rommelaere, Jean; Lacroix, Jeannine

    2016-05-19

    Combining virus-induced cytotoxic and immunotherapeutic effects, oncolytic virotherapy represents a promising therapeutic approach for high-grade glioma (HGG). A clinical trial has recently provided evidence for the clinical safety of the oncolytic parvovirus H-1 (H-1PV) in adult glioblastoma relapse patients. The present study assesses the efficacy of H-1PV in eliminating HGG initiating cells. H-1PV was able to enter and to transduce all HGG neurosphere culture models (n = 6), including cultures derived from adult glioblastoma, pediatric glioblastoma, and diffuse intrinsic pontine glioma. Cytotoxic effects induced by the virus have been observed in all HGG neurospheres at half maximal inhibitory concentration (IC50) doses of input virus between 1 and 10 plaque forming units per cell. H-1PV infection at this dose range was able to prevent tumorigenicity of NCH421k glioblastoma multiforme (GBM) "stem-like" cells in NOD/SCID mice. Interestingly NCH421R, an isogenic subclone with equal capacity of xenograft formation, but resistant to H-1PV infection could be isolated from the parental NCH421k culture. To reveal changes in gene expression associated with H-1PV resistance we performed a comparative gene expression analysis in these subclones. Several dysregulated genes encoding receptor proteins, endocytosis factors or regulators innate antiviral responses were identified and represent intriguing candidates for to further study molecular mechanisms of H-1PV resistance.

  2. Dynamic of distribution of human bone marrow-derived mesenchymal stem cells after transplantation into adult unconditioned mice.

    Science.gov (United States)

    Allers, Carolina; Sierralta, Walter D; Neubauer, Sonia; Rivera, Francisco; Minguell, José J; Conget, Paulette A

    2004-08-27

    The use of mesenchymal stem cells (MSC) for cell therapy relies on their capacity to engraft and survive long-term in the appropriate target tissue(s). Animal models have demonstrated that the syngeneic or xenogeneic transplantation of MSC results in donor engraftment into the bone marrow and other tissues of conditioned recipients. However, there are no reliable data showing the fate of human MSC infused into conditioned or unconditioned adult recipients. In the present study, the authors investigated, by using imaging, polymerase chain reaction (PCR), and in situ hybridization, the biodistribution of human bone marrow-derived MSC after intravenous infusion into unconditioned adult nude mice. As assessed by imaging (gamma camera), PCR, and in situ hybridization analysis, the authors' results demonstrate the presence of human MSC in bone marrow, spleen, and mesenchymal tissues of recipient mice. These results suggest that human MSC transplantation into unconditioned recipients represents an option for providing cellular therapy and avoids the complications associated with drugs or radiation conditioning.

  3. Transplanted Adult Neural Stem Cells Express Sonic Hedgehog In Vivo and Suppress White Matter Neuroinflammation after Experimental Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Genevieve M. Sullivan

    2017-01-01

    Full Text Available Neural stem cells (NSCs delivered intraventricularly may be therapeutic for diffuse white matter pathology after traumatic brain injury (TBI. To test this concept, NSCs isolated from adult mouse subventricular zone (SVZ were transplanted into the lateral ventricle of adult mice at two weeks post-TBI followed by analysis at four weeks post-TBI. We examined sonic hedgehog (Shh signaling as a candidate mechanism by which transplanted NSCs may regulate neuroregeneration and/or neuroinflammation responses of endogenous cells. Mouse fluorescent reporter lines were generated to enable in vivo genetic labeling of cells actively transcribing Shh or Gli1 after transplantation and/or TBI. Gli1 transcription is an effective readout for canonical Shh signaling. In ShhCreERT2;R26tdTomato mice, Shh was primarily expressed in neurons and was not upregulated in reactive astrocytes or microglia after TBI. Corroborating results in Gli1CreERT2;R26tdTomato mice demonstrated that Shh signaling was not upregulated in the corpus callosum, even after TBI or NSC transplantation. Transplanted NSCs expressed Shh in vivo but did not increase Gli1 labeling of host SVZ cells. Importantly, NSC transplantation significantly reduced reactive astrogliosis and microglial/macrophage activation in the corpus callosum after TBI. Therefore, intraventricular NSC transplantation after TBI significantly attenuated neuroinflammation, but did not activate host Shh signaling via Gli1 transcription.

  4. Low levels of endogenous or X-ray-induced DNA double-strand breaks activate apoptosis in adult neural stem cells.

    Science.gov (United States)

    Barazzuol, Lara; Rickett, Nicole; Ju, Limei; Jeggo, Penny A

    2015-10-01

    The embryonic neural stem cell compartment is characterised by rapid proliferation from embryonic day (E)11 to E16.5, high endogenous DNA double-strand break (DSB) formation and sensitive activation of apoptosis. Here, we ask whether DSBs arise in the adult neural stem cell compartments, the sub-ventricular zone (SVZ) of the lateral ventricles and the sub-granular zone (SGZ) of the hippocampal dentate gyrus, and whether they activate apoptosis. We used mice with a hypomorphic mutation in DNA ligase IV (Lig4(Y288C)), ataxia telangiectasia mutated (Atm(-/-)) and double mutant Atm(-/-)/Lig4(Y288C) mice. We demonstrate that, although DSBs do not arise at a high frequency in adult neural stem cells, the low numbers of DSBs that persist endogenously in Lig4(Y288C) mice or that are induced by low radiation doses can activate apoptosis. A temporal analysis shows that DSB levels in Lig4(Y288C) mice diminish gradually from the embryo to a steady state level in adult mice. The neonatal SVZ compartment of Lig4(Y288C) mice harbours diminished DSBs compared to its differentiated counterpart, suggesting a process selecting against unfit stem cells. Finally, we reveal high endogenous apoptosis in the developing SVZ of wild-type newborn mice. © 2015. Published by The Company of Biologists Ltd.

  5. Lunatic fringe-mediated Notch signaling regulates adult hippocampal neural stem cell maintenance.

    Science.gov (United States)

    Semerci, Fatih; Choi, William Tin-Shing; Bajic, Aleksandar; Thakkar, Aarohi; Encinas, Juan Manuel; Depreux, Frederic; Segil, Neil; Groves, Andrew K; Maletic-Savatic, Mirjana

    2017-07-12

    Hippocampal neural stem cells (NSCs) integrate inputs from multiple sources to balance quiescence and activation. Notch signaling plays a key role during this process. Here, we report that Lunatic fringe ( Lfng), a key modifier of the Notch receptor, is selectively expressed in NSCs. Further, Lfng in NSCs and Notch ligands Delta1 and Jagged1, expressed by their progeny, together influence NSC recruitment, cell cycle duration, and terminal fate. We propose a new model in which Lfng-mediated Notch signaling enables direct communication between a NSC and its descendants, so that progeny can send feedback signals to the 'mother' cell to modify its cell cycle status. Lfng-mediated Notch signaling appears to be a key factor governing NSC quiescence, division, and fate.

  6. The effects of viscoelastic polymer substrates on adult stem cell differentiation

    Science.gov (United States)

    Chang, Chungchueh; Fields, Adam; Ramek, Alex; Jurukovski, Vladimir; Simon, Marcia; Rafailovich, Miriam

    2009-03-01

    Dental Pulp Stem Cells (DPSCs) are known to differentiate in either bone, dentine, or nerve tissue by different environment signals. In this study, we have determined whether differentiation could only through modification of the substrate mechanics. Atomic Force Microscopy (AFM) on Shear Modulation Force Microscopy (SMFM) mode indicated that the spun-cast polybutadiene (PB) thin films could be used to provide different stiffness substrates by changing the thicknesses of thin films. DPSCs were then plated on these substrates and cultured in standard media. After 28 days incubation, Lasar Scanning Confocal Microscopy (LSCM) with mercury lamp indicated that the crystals were observed only on hard surfaces. The Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX analysis) indicated that the crystals are calcium phosphates. The Glancing Incidence Diffraction (GID) was also used to determine the structure of crystals. These results indicate that DPSCs could be differentiated into osteoblasts by mechanical stimuli from substrate mechanics.

  7. Immortal DNA strand cosegregation requires p53/IMPDH-dependent asymmetric self-renewal associated with adult stem cells.

    Science.gov (United States)

    Rambhatla, Lakshmi; Ram-Mohan, Sumati; Cheng, Jennifer J; Sherley, James L

    2005-04-15

    Because they are long-lived and cycle continuously, adult stem cells (ASCs) are predicted as the most common precursor for cancers in adult mammalian tissues. Two unique attributes have been proposed to restrict the carcinogenic potential of ASCs. These are asymmetric self-renewal that limits their number and immortal DNA strand cosegregation that limits their accumulation of mutations due to DNA replication errors. Until recently, the molecular basis and regulation of these important ASC-specific functions were unknown. We developed engineered cultured cells that exhibit asymmetric self-renewal and immortal DNA strand cosegregation. These model cells were used to show that both ASC-specific functions are regulated by the p53 cancer gene. Previously, we proposed that IMP dehydrogenase (IMPDH) was an essential factor for p53-dependent asymmetric self-renewal. We now confirm this proposal and provide quantitative evidence that asymmetric self-renewal is acutely sensitive to even modest changes in IMPDH expression. These analyses reveal that immortal DNA strand cosegregation is also regulated by IMPDH and confirm the original implicit precept that immortal DNA strand cosegregation is specific to cells undergoing asymmetric self-renewal (i.e., ASCs). With IMPDH being the rate-determining enzyme for guanine ribonucleotide (rGNP) biosynthesis, its requirement implicates rGNPs as important regulators of ASC asymmetric self-renewal and immortal DNA strand cosegregation. An in silico analysis of global gene expression data from human cancer cell lines underscored the importance of p53-IMPDH-rGNP regulation for normal tissue cell kinetics, providing further support for the concept that ASCs are key targets for adult tissue carcinogenesis.

  8. Endogenous neural stem cells in central canal of adult rats acquired limited ability to differentiate into neurons following mild spinal cord injury

    Science.gov (United States)

    Liu, Yuan; Tan, Botao; Wang, Li; Long, Zaiyun; Li, Yingyu; Liao, Weihong; Wu, Yamin

    2015-01-01

    Endogenous neural stem cells in central canal of adult mammalian spinal cord exhibit stem cell properties following injury. In the present study, the endogenous neural stem cells were labeled with Dil to track the differentiation of cells after mild spinal cord injury (SCI). Compared with 1 and 14 days post mild injury, the number of endogenous neural stem cells significantly increased at the injured site of spinal cord on 3 and 7 days post-injury. Dil-labeled βIII-tublin and GFAP expressing cells could be detected on 7 days post-injury, which indicated that the endogenous neural stem cells in central canal of spinal cord differentiated into different type of neural cells, but there were more differentiated astrocytes than the neurons after injury. Furthermore, after injury the expression of inhibitory Notch1 and Hes1 mRNA began to increase at 6 hours and was evident at 12 and 24 hours, which maintained high levels up to 7 days post-injury. These results indicated that a mild SCI in rat is sufficient to induce endogenous neural stem cells proliferation and differentiation. However, the ability to differentiate into neurons is limited, which may be, at least in part, due to high expression of inhibitory Notch1 and Hes1 genes after injury. PMID:26097566

  9. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland

    OpenAIRE

    Joanna Pyczek; Rolf Buslei; David Schult; Annett Hölsken; Michael Buchfelder; Ina Heß; Heidi Hahn; Anja Uhmann

    2016-01-01

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and S...

  10. C. elegans nucleostemin is required for larval growth and germline stem cell division.

    Directory of Open Access Journals (Sweden)

    Michelle M Kudron

    2008-08-01

    Full Text Available The nucleolus has shown to be integral for many processes related to cell growth and proliferation. Stem cells in particular are likely to depend upon nucleolus-based processes to remain in a proliferative state. A highly conserved nucleolar factor named nucleostemin is proposed to be a critical link between nucleolar function and stem-cell-specific processes. Currently, it is unclear whether nucleostemin modulates proliferation by affecting ribosome biogenesis or by another nucleolus-based activity that is specific to stem cells and/or highly proliferating cells. Here, we investigate nucleostemin (nst-1 in the nematode C. elegans, which enables us to examine nst-1 function during both proliferation and differentiation in vivo. Like mammalian nucleostemin, the NST-1 protein is localized to the nucleolus and the nucleoplasm; however, its expression is found in both differentiated and proliferating cells. Global loss of C. elegans nucleostemin (nst-1 leads to a larval arrest phenotype due to a growth defect in the soma, while loss of nst-1 specifically in the germ line causes germline stem cells to undergo a cell cycle arrest. nst-1 mutants exhibit reduced levels of rRNAs, suggesting defects in ribosome biogenesis. However, NST-1 is generally not present in regions of the nucleolus where rRNA transcription and processing occurs, so this reduction is likely secondary to a different defect in ribosome biogenesis. Transgenic studies indicate that NST-1 requires its N-terminal domain for stable expression and both its G1 GTPase and intermediate domains for proper germ line function. Our data support a role for C. elegans nucleostemin in cell growth and proliferation by promoting ribosome biogenesis.

  11. Hematopoietic stem cell transplantation in children and young adults with secondary myelodysplastic syndrome and acute myelogenous leukemia after aplastic anemia.

    Science.gov (United States)

    Yoshimi, Ayami; Strahm, Brigitte; Baumann, Irith; Furlan, Ingrid; Schwarz, Stephan; Teigler-Schlegel, Andrea; Walther, Joachim-Ulrich; Schlegelberger, Brigitte; Göhring, Gudrun; Nöllke, Peter; Führer, Monika; Niemeyer, Charlotte M

    2014-03-01

    Secondary myelodysplastic syndrome and acute myelogenous leukemia (sMDS/sAML) are the most serious secondary events occurring after immunosuppressive therapy in patients with aplastic anemia. Here we evaluate the outcome of hematopoietic stem cell transplantation (HSCT) in 17 children and young adults with sMDS/sAML after childhood aplastic anemia. The median interval between the diagnosis of aplastic anemia and the development of sMDS/sAML was 2.9 years (range, 1.2 to 13.0 years). At a median age of 13.1 years (range, 4.4 to 26.7 years), patients underwent HSCT with bone marrow (n = 6) or peripheral blood stem cell (n = 11) grafts from HLA-matched sibling donors (n = 2), mismatched family donors (n = 2), or unrelated donors (n = 13). Monosomy 7 was detected in 13 patients. The preparative regimen consisted of busulfan, cyclophosphamide, and melphalan in 11 patients and other agents in 6 patients. All patients achieved neutrophil engraftment. The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) was 47%, and that of chronic GVHD was 70%. Relapse occurred in 1 patient. The major cause of death was transplant-related complication (n = 9). Overall survival and event-free survival at 5 years after HSCT were both 41%. In summary, this study indicates that HSCT is a curative therapy for some patients with sMDS/sAML after aplastic anemia. Future efforts should focus on reducing transplantation-related mortality. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  12. Adult zebrafish intestine resection: a novel model of short bowel syndrome, adaptation, and intestinal stem cell regeneration.

    Science.gov (United States)

    Schall, K A; Holoyda, K A; Grant, C N; Levin, D E; Torres, E R; Maxwell, A; Pollack, H A; Moats, R A; Frey, M R; Darehzereshki, A; Al Alam, D; Lien, C; Grikscheit, T C

    2015-08-01

    Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation. Copyright © 2015 the American Physiological Society.

  13. Inhibition of Thrombopoietin/Mpl Signaling in Adult Hematopoiesis Identifies New Candidates for Hematopoietic Stem Cell Maintenance.

    Science.gov (United States)

    Kohlscheen, Saskia; Wintterle, Sabine; Schwarzer, Adrian; Kamp, Christel; Brugman, Martijn H; Breuer, Daniel C; Büsche, Guntram; Baum, Christopher; Modlich, Ute

    2015-01-01

    Thrombopoietin (Thpo) signals via its receptor Mpl and regulates megakaryopoiesis, hematopoietic stem cell (HSC) maintenance and post-transplant expansion. Mpl expression is tightly controlled and deregulation of Thpo/Mpl-signaling is linked to hematological disorders. Here, we constructed an intracellular-truncated, signaling-deficient Mpl protein which is presented on the cell surface (dnMpl). The transplantation of bone marrow cells retrovirally transduced to express dnMpl into wildtype mice induced thrombocytopenia, and a progressive loss of HSC. The aplastic BM allowed the engraftment of a second BM transplant without further conditioning. Functional analysis of the truncated Mpl in vitro and in vivo demonstrated no internalization after Thpo binding and the inhibition of Thpo/Mpl-signaling in wildtype cells due to dominant-negative (dn) effects by receptor competition with wildtype Mpl for Thpo binding. Intracellular inhibition of Mpl could be excluded as the major mechanism by the use of a constitutive-dimerized dnMpl. To further elucidate the molecular changes induced by Thpo/Mpl-inhibition on the HSC-enriched cell population in the BM, we performed gene expression analysis of Lin-Sca1+cKit+ (LSK) cells isolated from mice transplanted with dnMpl transduced BM cells. The gene expression profile supported the exhaustion of HSC due to increased cell cycle progression and identified new and known downstream effectors of Thpo/Mpl-signaling in HSC (namely TIE2, ESAM1 and EPCR detected on the HSC-enriched LSK cell population). We further compared gene expression profiles in LSK cells of dnMpl mice with human CD34+ cells of aplastic anemia patients and identified similar deregulations of important stemness genes in both cell populations. In summary, we established a novel way of Thpo/Mpl inhibition in the adult mouse and performed in depth analysis of the phenotype including gene expression profiling.

  14. Calpain Determines the Propensity of Adult Hippocampal Neural Stem Cells to Autophagic Cell Death Following Insulin Withdrawal.

    Science.gov (United States)

    Chung, Kyung Min; Park, Hyunhee; Jung, Seonghee; Ha, Shinwon; Yoo, Seung-Jun; Woo, Hanwoong; Lee, Hyang Ju; Kim, Seong Who; Kim, Eun-Kyoung; Moon, Cheil; Yu, Seong-Woon

    2015-10-01

    Programmed cell death (PCD) has significant effects on the function of neural stem cells (NSCs) during brain development and degeneration. We have previously reported that adult rat hippocampal neural stem (HCN) cells underwent autophagic cell death (ACD) rather than apoptosis following insulin withdrawal despite their intact apoptotic capabilities. Here, we report a switch in the mode of cell death in HCN cells with calpain as a critical determinant. In HCN cells, calpain 1 expression was barely detectable while calpain 2 was predominant. Inhibition of calpain in insulin-deprived HCN cells further augmented ACD. In contrast, expression of calpain 1 switched ACD to apoptosis. The proteasome inhibitor lactacystin blocked calpain 2 degradation and elevated the intracellular Ca(2+) concentration. In combination, these effects potentiated calpain activity and converted the mode of cell death to apoptosis. Our results indicate that low calpain activity, due to absence of calpain 1 and degradation of calpain 2, results in a preference for ACD over apoptosis in insulin-deprived HCN cells. On the other hand, conditions leading to high calpain activity completely switch the mode of cell death to apoptosis. This is the first report on the PCD mode switching mechanism in NSCs. The dynamic change in calpain activity through the proteasome-mediated modulation of the calpain and intracellular Ca(2+) levels may be the critical contributor to the demise of NSCs. Our findings provide a novel insight into the complex mechanisms interconnecting autophagy and apoptosis and their roles in the regulation of NSC death. © 2015 AlphaMed Press.

  15. Adult Bone Marrow Mesenchymal Stem Cells Primed for fhe Repair of Damaged Cardiac Tissue After Myocardial Infarction

    Science.gov (United States)

    Marks, Edward D.

    The burden of cardiovascular disease around the world is growing, despite improvements in hospital care and time to treatment. As more people survive an initial myocardial infarction (MI), the decompensated heart tissue is strained, leading to heart failure (HF) and an increased risk for a second MI. While extensive progress has been made in treating the symptoms after MI, including HF and angina, little success has come from repairing the damaged heart tissue to alleviate the progression to these end- stage symptoms. One promising area of regenerative research has been the use of adult stem cells, particularly from the bone marrow (BMSCs). These cells can differentiate towards the cardiac cell lineage in vitro while producing trophic factors that can repair damaged tissue. When placed in the heart after MI though, BMSCs have mixed results, producing profound changes in some patients but zero or even negative effects in others. In this report, we used BMSCs as a stem cell base for a regenerative medicine system for the repair of damaged cardiac tissue. These cells are seeded on a polycaprolactone nanoscaffolding support system, which provides a growth substrate for in vitro work, as well as a housing system for protected in vivo delivery. When the nanoscaffold is pre-coated with a novel combination of a cardiac protein, thymosin beta4 (Tbeta4), and a small molecule effector of the WNT protein pathway, IWP-2, BMSCs differentiated towards the cardiac lineage in as little as 24hours. When injected into rat hearts that have been given an ischemic MI, the nanoscaffolding system slowly dissolves, leaving the cells in place of the damaged cardiac tissue. After two weeks of monitoring, BMSCs are present within the damaged hearts, as evidenced by immunofluorescence and nanoparticle tracking. Injections of the nanoscaffolding/cell system led to robust healing of the rat hearts that had been given small- and medium- damage heart attacks, outperforming PBS sham and cell

  16. Adult hematopoietic stem cells lacking Hif-1α self-renew normally

    Science.gov (United States)

    Vukovic, Milica; Sepulveda, Catarina; Subramani, Chithra; Guitart, Amélie V.; Mohr, Jasmine; Allen, Lewis; Panagopoulou, Theano I.; Paris, Jasmin; Lawson, Hannah; Villacreces, Arnaud; Armesilla-Diaz, Alejandro; Gezer, Deniz; Holyoake, Tessa L.; Ratcliffe, Peter J.

    2016-01-01

    The hematopoietic stem cell (HSC) pool is maintained under hypoxic conditions within the bone marrow microenvironment. Cellular responses to hypoxia are largely mediated by the hypoxia-inducible factors, Hif-1 and Hif-2. The oxygen-regulated α subunits of Hif-1 and Hif-2 (namely, Hif-1α and Hif-2α) form dimers with their stably expressed β subunits and control the transcription of downstream hypoxia-responsive genes to facilitate adaptation to low oxygen tension. An initial study concluded that Hif-1α is essential for HSC maintenance, whereby Hif-1α–deficient HSCs lost their ability to self-renew in serial transplantation assays. In another study, we demonstrated that Hif-2α is dispensable for cell-autonomous HSC maintenance, both under steady-state conditions and following transplantation. Given these unexpected findings, we set out to revisit the role of Hif-1α in cell-autonomous HSC functions. Here we demonstrate that inducible acute deletion of Hif-1α has no impact on HSC survival. Notably, unstressed HSCs lacking Hif-1α efficiently self-renew and sustain long-term multilineage hematopoiesis upon serial transplantation. Finally, Hif-1α–deficient HSCs recover normally after hematopoietic injury induced by serial administration of 5-fluorouracil. We therefore conclude that despite the hypoxic nature of the bone marrow microenvironment, Hif-1α is dispensable for cell-autonomous HSC maintenance. PMID:27060169

  17. Very small embryonic-like stem cells (VSELs) detected in azoospermic testicular biopsies of adult survivors of childhood cancer.

    Science.gov (United States)

    Kurkure, Purna; Prasad, Maya; Dhamankar, Vandana; Bakshi, Ganesh

    2015-11-09

    Infertility is a known side-effect of oncotherapy in cancer survivors, and often compromises the quality of life. The present study was undertaken to detect very small embryonic-like stem cells (VSELs) in testicular biopsies from young adult survivors of childhood cancer who had azoospermia. VSELs have been earlier reported in human and mouse testes. They resist busulphan treatment in mice and potentially restore spermatogenesis when the somatic niche is restored by transplanting Sertoli or mesenchymal cells. VSELs also have the potential to differentiate into sperm in vitro. The study had clearance from Institutional review board (IRB). Seven azoospermic survivors of childhood cancer were included in the study after obtaining their informed consent. Semen analysis was done to confirm azoospermia prior to inclusion in the study. Testicular biopsies were performed at the Uro-oncology Unit of the hospital and then used for various studies to detect VSELs. Hematoxylin and Eosin stained tubular sections confirmed azoospermia and smears revealed the presence of very small, spherical VSELs with high nucleo-cytoplasmic ratio, in addition to the Sertoli cells. Immuno-localization studies on testicular smears showed that the VSELs were CD133+/CD45-/LIN-, expressed nuclear OCT-4, STELLA and cell surface SSEA-4. Pluripotent transcripts Oct-4A, Nanog and Sox-2 were detected in azoospermic samples whereas marked reduction was observed in germ cell markers Oct-4 and Boule. The present study demonstrates the presence of pluripotent VSELs in the testicular biopsy of azoospermic adult survivors of childhood cancer. It is likely that these persisting VSELs can restore spermatogenesis as demonstrated in mice studies. Therefore, pilot studies need to be undertaken using autologous mesenchymal cells with a hope to restore testicular function and fertility in cancer survivors. The results of this study assume a great significance in the current era, where cryopreservation of testicular

  18. c-kitpos GATA-4 high rat cardiac stem cells foster adult cardiomyocyte survival through IGF-1 paracrine signalling.

    Directory of Open Access Journals (Sweden)

    Nanako Kawaguchi

    2010-12-01

    Full Text Available Resident c-kit positive (c-kitpos cardiac stem cells (CSCs could be considered the most appropriate cell type for myocardial regeneration therapies. However, much is still unknown regarding their biological properties and potential.We produced clones of high and low expressing GATA-4 CSCs from long-term bulk-cultured c-kitpos CSCs isolated from adult rat hearts. When c-kitpos GATA-4 high expressing clonal CSCs (cCSCs were co-cultured with adult rat ventricular cardiomyocytes, we observed increased survival and contractility of the cardiomyocytes, compared to cardiomyocytes cultured alone, co-cultured with fibroblasts or c-kitpos GATA-4 low expressing cCSCs. When analysed by ELISA, the concentration of IGF-1 was significantly increased in the c-kitpos GATA-4 high cCSC/cardiomyocyte co-cultures and there was a significant correlation between IGF-1 concentration and cardiomyocyte survival. We showed the activation of the IGF-1 receptor and its downstream molecular targets in cardiomyocytes co-cultured with c-kitpos GATA-4 high cCSCs but not in cardiomyocytes that were cultured alone, co-cultured with fibroblasts or c-kitpos GATA-4 low cCSCs. Addition of a blocking antibody specific to the IGF-1 receptor inhibited the survival of cardiomyocytes and prevented the activation of its signalling in cardiomyocytes in the c-kitpos GATA-4 high cCSC/cardiomyocyte co-culture system. IGF-1 supplementation or IGF-1 high conditioned medium taken from the co-culture of c-kitpos GATA-4 high cCSCs plus cardiomyocytes did extend the survival and contractility of cardiomyocytes cultured alone and cardiomyocytes co-cultured with c-kitpos GATA-4 low cCSCs.c-kitpos GATA-4 high cCSCs exert a paracrine survival effect on cardiomyocytes through induction of the IGF-1R and signalling pathway.

  19. Effects of Healing Touch and Relaxation Therapy on Adult Patients Undergoing Hematopoietic Stem Cell Transplant: A Feasibility Pilot Study.

    Science.gov (United States)

    Lu, Der-Fa; Hart, Laura K; Lutgendorf, Susan K; Oh, Hyunkyoung; Silverman, Margarida

    2016-01-01

    Stem cell transplant (SCT), considered the current standard of care for adults with advanced cancers, can lead to substantial deconditioning and diminished well-being. Attending to life quality of SCT recipients is now viewed as essential. The objective of this study was to identify the feasibility and preliminary efficacy of healing touch (HT) and relaxation therapy (RT) with patients undergoing SCT. A randomized prospective design compared 13 SCT patients who received HT daily while hospitalized to 13 similar SCT patients who received daily RT. The clinical outcomes of the 2 groups were also compared with retrospective clinical data of 20 patients who received SCT during the same year. The mean age of participants was 57 years, with 54% receiving autologous and 46% receiving allogeneic transplants. All patients assigned to the HT group completed the protocol. Only 60% of the relaxation group completed the intervention. Both interventions produced improvement in psychosocial measures and a shorter hospital length of stay (LOS) than the historical group. Differential results for LOS were related to the type of transplant received. The LOS differences were not statistically significant but could be clinically significant. Healing touch was a better tolerated modality by this population. Future research is needed to validate the LOS advantage of the HT and RT interventions, explore the differences in effect found with different transplant types, and identify patients who can tolerate RT. The LOS reduction could result in decreased cost. Second, mood and function improvements support quality of life during SCT treatment.

  20. Conversion of adult human peripheral blood mononuclear cells into induced neural stem cell by using episomal vectors

    Directory of Open Access Journals (Sweden)

    Xihe Tang

    2016-03-01

    Full Text Available Human neural stem cells (NSCs hold great promise for research and therapy in neural diseases. Many studies have shown direct induction of NSCs from human fibroblasts, which require an invasive skin biopsy and a prolonged period of expansion in cell culture prior to use. Peripheral blood (PB is routinely used in medical diagnoses, and represents a noninvasive and easily accessible source of cells. Here we show direct derivation of NSCs from adult human PB mononuclear cells (PB-MNCs by employing episomal vectors for transgene delivery. These induced NSCs (iNSCs can expand more than 60 passages, can exhibit NSC morphology, gene expression, differentiation potential, and self-renewing capability and can give rise to multiple functional neural subtypes and glial cells in vitro. Furthermore, the iNSCs carry a specific regional identity and have electrophysiological activity upon differentiation. Our findings provide an easily accessible approach for generating human iNSCs which will facilitate disease modeling, drug screening, and possibly regenerative medicine.

  1. Prion protein cleavage fragments regulate adult neural stem cell quiescence through redox modulation of mitochondrial fission and SOD2 expression.

    Science.gov (United States)

    Collins, Steven J; Tumpach, Carolin; Groveman, Bradley R; Drew, Simon C; Haigh, Cathryn L

    2018-03-24

    Neurogenesis continues in the post-developmental brain throughout life. The ability to stimulate the production of new neurones requires both quiescent and actively proliferating pools of neural stem cells (NSCs). Actively proliferating NSCs ensure that neurogenic demand can be met, whilst the quiescent pool makes certain NSC reserves do not become depleted. The processes preserving the NSC quiescent pool are only just beginning to be defined. Herein, we identify a switch between NSC proliferation and quiescence through changing intracellular redox signalling. We show that N-terminal post-translational cleavage products of the prion protein (PrP) induce a quiescent state, halting NSC cellular growth, migration, and neurite outgrowth. Quiescence is initiated by the PrP cleavage products through reducing intracellular levels of reactive oxygen species. First, inhibition of redox signalling results in increased mitochondrial fission, which rapidly signals quiescence. Thereafter, quiescence is maintained through downstream increases in the expression and activity of superoxide dismutase-2 that reduces mitochondrial superoxide. We further observe that PrP is predominantly cleaved in quiescent NSCs indicating a homeostatic role for this cascade. Our findings provide new insight into the regulation of NSC quiescence, which potentially could influence brain health throughout adult life.

  2. Interaction of adult human neural crest-derived stem cells with a nanoporous titanium surface is sufficient to induce their osteogenic differentiation

    Directory of Open Access Journals (Sweden)

    Matthias Schürmann

    2014-07-01

    Full Text Available Osteogenic differentiation of various adult stem cell populations such as neural crest-derived stem cells is of great interest in the context of bone regeneration. Ideally, exogenous differentiation should mimic an endogenous differentiation process, which is partly mediated by topological cues. To elucidate the osteoinductive potential of porous substrates with different pore diameters (30 nm, 100 nm, human neural crest-derived stem cells isolated from the inferior nasal turbinate were cultivated on the surface of nanoporous titanium covered membranes without additional chemical or biological osteoinductive cues. As controls, flat titanium without any topological features and osteogenic medium was used. Cultivation of human neural crest-derived stem cells on 30 nm pores resulted in osteogenic differentiation as demonstrated by alkaline phosphatase activity after seven days as well as by calcium deposition after 3 weeks of cultivation. In contrast, cultivation on flat titanium and on membranes equipped with 100 nm pores was not sufficient to induce osteogenic differentiation. Moreover, we demonstrate an increase of osteogenic transcripts including Osterix, Osteocalcin and up-regulation of Integrin β1 and α2 in the 30 nm pore approach only. Thus, transplantation of stem cells pre-cultivated on nanostructured implants might improve the clinical outcome by support of the graft adherence and acceleration of the regeneration process.

  3. Hematopoietic Stem Cell Transplant in Adolescent and Young Adults With Fanconi Anemia Is Feasible With Acceptable Toxicity, With Those Surviving 100 Days Posttransplant Having Excellent Outcomes.

    Science.gov (United States)

    Alhuraiji, Ahmad; Alzahrani, Hazza; Al Mohareb, Fahad; Chaudhri, Naeem; Alsharif, Fahad; Mohamed, Said; Rasheed, Walid; Aldawsari, Ghuzayel; Ahmed, Syed Osman; Aljurf, Mahmoud

    2016-12-01

    Fanconi anemia is a congenital bone marrow failure syndrome that is associated with congenital anomalies and increased risk of cancer. Hematopoietic stem cell transplant is a potentially curative modality for bone marrow failure in Fanconi anemia patients. Here, we report our center's experience regarding adolescent and young adult patients with Fanconi anemia and hematopoietic stem cell transplant. We conducted a retrospective patient record analyses of patients who presented at our center from 1988 to 2014. We included patients greater than 14 years old with confirmed Fanconi anemia based on positive chromosome breakage study and who underwent hematopoietic stem cell transplant at our institution. Our study group comprised 12 patients with Fanconi anemia who underwent hematopoietic stem cell transplant at our institution. The median age was 20 years (range, 14-31 y) with a female predominance of 83%. Low-dose cyclophosphamide (20-80 mg/kg)-based conditioning regimens were used with different combinations that included fludarabine, antithymocyte globulin, or total body irradiation. All patients had HLA-matched sibling grafts. In all patients, stem cell source was the bone marrow. All patients showed engraftment. Four patients (33%) developed acute graft-versus-host disease. Three patients (25%) died early before day 100 after hematopoietic stem cell transplant due to infectious complications, with 1 patient having steroid refractory acute graft-versus-host disease. Overall survival was 75% at a median follow-up of 43 months. All patients who survived are well and remained transfusion independent without evidence of secondary malignancy. Our findings support the feasibility of reduced intensity conditioning allogeneic hematopoietic stem cell transplant in older and more heavily pretreated patients with Fanconi anemia, especially for those who are engrafted.

  4. Impact of conditioning with TBI in adult patients with T-cell ALL who receive a myeloablative allogeneic stem cell transplantation

    DEFF Research Database (Denmark)

    Cahu, X; Labopin, M; Giebel, S

    2016-01-01

    Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a therapeutic option for adult patients with T-cell ALL (T-ALL). Meanwhile, few allo-SCT data specific to adult T-ALL have been described thus far. Specifically, the optimal myeloablative conditioning regimen is unknown...... patients with T-ALL entitled to receive a myeloablative allo-SCT may benefit from TBI-based regimens.Bone Marrow Transplantation advance online publication, 30 November 2015; doi:10.1038/bmt.2015.278....

  5. Vitamin A/Retinol and Maintenance of Pluripotency of Stem Cells

    Directory of Open Access Journals (Sweden)

    Jaspal S. Khillan

    2014-03-01

    Full Text Available Retinol, the alcohol form of vitamin A is a key dietary component that plays a critical role in vertebrate development, cell differentiation, reproduction, vision and immune system. Natural and synthetic analogs of retinol, called retinoids, have generally been associated with the cell differentiation via retinoic acid which is the most potent metabolite of retinol. However, a direct function of retinol has not been fully investigated. New evidence has now emerged that retinol supports the self-renewal of stem cells including embryonic stem cells (ESCs, germ line stem cells (GSCs and cancer stem cells (CSCs by activating the endogenous machinery for self-renewal by a retinoic acid independent mechanism. The studies have also revealed that stem cells do not contain enzymes that are responsible for metabolizing retinol into retinoic acid. This new function of retinol may have important implications for stem cell biology which can be exploited for quantitative production of pure population of pluripotent stem cells for regenerative medicine as well as clinical applications for cancer therapeutics.

  6. Comparison of osteo/odontogenic differentiation of human adult dental pulp stem cells and stem cells from apical papilla in the presence of platelet lysate.

    Science.gov (United States)

    Abuarqoub, Duaa; Awidi, Abdalla; Abuharfeil, Nizar

    2015-10-01

    Human dental pulp cells (DPSCs) and stem cells from apical papilla have been used for the repair of damaged tooth tissues. Human platelet lysate (PL) has been suggested as a substitute for fetal bovine serum (FBS) for large scale expansion of dental stem cells. However, biological effects and optimal concentrations of PL for proliferation and differentiation of human dental stem cells remain to be elucidated. DPSCs and SCAP cells were isolated from impacted third molars of young healthy donors, at the stage of root development and identified by markers using flow cytometry. For comparison the cells were cultured in media containing PL (1%, 5% and 10%) and FBS, with subsequent induction for osteogenic/odontogenic differentiation. The cultures were analyzed for; morphology, growth characteristics, mineralization potential (Alizarin Red method) and differentiation markers using ELISA and real time -polymerase chain reaction (qPCR). The proliferation rates of DPSCs and SCAP significantly increased when cells were treated with 5% PL (7X doubling time) as compared to FBS. 5% PL also enhanced mineralized differentiation of DPSCs and SCAP, as indicated by the measurement of alkaline phosphatase activity, osteocalcin and osteopontin, calcium deposition and q-PCR. Our findings suggest that using 5% platelet lysate, proliferation and osteo/odontogenesis of DPSCs and SCAP for a short period of time (15 days), was significantly improved. This may imply its use as an optimum concentration for expansion of dental stem cells in bone regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. What is a stem cell?

    Science.gov (United States)

    Slack, Jonathan M W

    2018-05-15

    The historical roots of the stem cell concept are traced with respect to its usage in embryology and in hematology. The modern consensus definition of stem cells, comprising both pluripotent stem cells in culture and tissue-specific stem cells in vivo, is explained and explored. Methods for identifying stem cells are discussed with respect to cell surface markers, telomerase, label retention and transplantability, and properties of the stem cell niche are explored. The CreER method for identifying stem cells in vivo is explained, as is evidence in favor of a stochastic rather than an obligate asymmetric form of cell division. In conclusion, it is found that stem cells do not possess any unique and specific molecular markers; and stem cell behavior depends on the environment of the cell as well as the stem cell's intrinsic qualities. Furthermore, the stochastic mode of division implies that stem cell behavior is a property of a cell population not of an individual cell. In this sense, stem cells do not exist in isolation but only as a part of multicellular system. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Methods and Principles Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells. © 2018 Wiley Periodicals, Inc.

  8. Tracing the destiny of mesenchymal stem cells from embryo to adult bone marrow and white adipose tissue via Pdgfrα expression.

    Science.gov (United States)

    Miwa, Hiroyuki; Era, Takumi

    2018-01-29

    Mesenchymal stem cells (MSCs) are somatic stem cells that can be derived from adult bone marrow (BM) and white adipose tissue (WAT), and that display multipotency and self-renewal capacity. Although MSCs are essential for tissue formation and have already been used in clinical therapy, the origins and markers of these cells remain unknown. In this study, we first investigated the developmental process of MSCs in mouse embryos using the gene encoding platelet-derived growth factor receptor α ( Pdgfra ) as a marker. We then traced cells expressing Pdgfra and other genes (brachyury, Sox1 and Pmx1 ) in various mutant mouse embryos until the adult stage. This tracing of MSC origins and destinies indicates that embryonic MSCs emerge in waves and that almost all adult BM MSCs and WAT MSCs originate from mesoderm and embryonic Pdgfrα-positive cells. Furthermore, we demonstrate that adult Pdgfrα-positive cells are involved in some pathological conditions. © 2018. Published by The Company of Biologists Ltd.

  9. 70th Birthday symposium of Prof. Dr. Riederer: autologous adult stem cells in ischemic and traumatic CNS disorders

    NARCIS (Netherlands)

    de Munter, J.P.J.M.; Wolters, E.C.

    2013-01-01

    Ischemic and traumatic insults of the central nervous system both result in definite chronic disability, only to some extent responsive to rehabilitation. Recently, the application of autologous stem cells (fresh bone marrow-derived mononuclear cells including mesenchymal and hematopoietic stem

  10. c-Kit-mediated functional positioning of stem cells to their niches is essential for maintenance and regeneration of adult hematopoiesis.

    Directory of Open Access Journals (Sweden)

    Yuki Kimura

    Full Text Available The mechanism by which hematopoietic stem and progenitor cells (HSPCs through interaction with their niches maintain and reconstitute adult hematopoietic cells is unknown. To functionally and genetically track localization of HSPCs with their niches, we employed novel mutant loxPs, lox66 and lox71 and Cre-recombinase technology to conditionally delete c-Kit in adult mice, while simultaneously enabling GFP expression in the c-Kit-deficient cells. Conditional deletion of c-Kit resulted in hematopoietic failure and splenic atrophy both at steady state and after marrow ablation leading to the demise of the treated adult mice. Within the marrow, the c-Kit-expressing GFP(+ cells were positioned to Kit ligand (KL-expressing niche cells. This c-Kit-mediated cellular adhesion was essential for long-term maintenance and expansion of HSPCs. These results lay the foundation for delivering KL within specific niches to maintain and restore hematopoiesis.

  11. A septo-temporal molecular gradient of sfrp3 in the dentate gyrus differentially regulates quiescent adult hippocampal neural stem cell activation.

    Science.gov (United States)

    Sun, Jiaqi; Bonaguidi, Michael A; Jun, Heechul; Guo, Junjie U; Sun, Gerald J; Will, Brett; Yang, Zhengang; Jang, Mi-Hyeon; Song, Hongjun; Ming, Guo-li; Christian, Kimberly M

    2015-09-04

    A converging body of evidence indicates that levels of adult hippocampal neurogenesis vary along the septo-temporal axis of the dentate gyrus, but the molecular mechanisms underlying this regional heterogeneity are not known. We previously identified a niche mechanism regulating proliferation and neuronal development in the adult mouse dentate gyrus resulting from the activity-regulated expression of secreted frizzled-related protein 3 (sfrp3) by mature neurons, which suppresses activation of radial glia-like neural stem cells (RGLs) through inhibition of Wingless/INT (WNT) protein signaling. Here, we show that activation rates within the quiescent RGL population decrease gradually along the septo-temporal axis in the adult mouse dentate gyrus, as defined by MCM2 expression in RGLs. Using in situ hybridization and quantitative real-time PCR, we identified an inverse septal-to-temporal increase in the expression of sfrp3 that emerges during postnatal development. Elimination of sfrp3 and its molecular gradient leads to increased RGL activation, preferentially in the temporal region of the adult dentate gyrus. Our study identifies a niche mechanism that contributes to the graded distribution of neurogenesis in the adult dentate gyrus and has important implications for understanding functional differences associated with adult hippocampal neurogenesis along the septo-temporal axis.

  12. Exophytic pilocytic astrocytoma of the brain stem in an adult with encasement of the caudal cranial nerve complex (IX-XII): presurgical anatomical neuroimaging using MRI

    Energy Technology Data Exchange (ETDEWEB)

    Yousry, Indra; Yousry, Tarek A. [Department of Neuroradiology, Klinikum Grosshadern, Ludwig-Maximilians University, Marchioninistr. 15, 81377, Munich (Germany); Muacevic, Alexander; Olteanu-Nerbe, Vlad [Department of Neurosurgery, Klinikum Grosshadern, Ludwig-Maximilians University, Munich (Germany); Naidich, Thomas P. [Department of Radiology, Section of Neuroradiology, Mount Sinai Hospital, New York (United States)

    2004-07-01

    We describe a rare case of adult pilocytic astrocytoma in which exophytic growth from the brain stem presented as a right cerebellopontine angle mass. An initial MRI examination using T2- and T1-weighted images without and with contrast suggested the diagnosis of schwannoma. Subsequent use of 3D CISS (three-dimensional constructive interference in steady state) and T1-weighted contrast-enhanced 3D MP-RAGE (three-dimensional magnetization prepared rapid acquisition gradient echo) sequences led to the diagnosis of an exophytic brain stem tumor, documented the precise relationships of the tumor to cranial nerve VIII, revealed encasement of cranial nerves IX-XII (later confirmed intraoperatively), and provided the proper basis for planning surgical management. (orig.)

  13. Exophytic pilocytic astrocytoma of the brain stem in an adult with encasement of the caudal cranial nerve complex (IX-XII): presurgical anatomical neuroimaging using MRI

    International Nuclear Information System (INIS)

    Yousry, Indra; Yousry, Tarek A.; Muacevic, Alexander; Olteanu-Nerbe, Vlad; Naidich, Thomas P.

    2004-01-01

    We describe a rare case of adult pilocytic astrocytoma in which exophytic growth from the brain stem presented as a right cerebellopontine angle mass. An initial MRI examination using T2- and T1-weighted images without and with contrast suggested the diagnosis of schwannoma. Subsequent use of 3D CISS (three-dimensional constructive interference in steady state) and T1-weighted contrast-enhanced 3D MP-RAGE (three-dimensional magnetization prepared rapid acquisition gradient echo) sequences led to the diagnosis of an exophytic brain stem tumor, documented the precise relationships of the tumor to cranial nerve VIII, revealed encasement of cranial nerves IX-XII (later confirmed intraoperatively), and provided the proper basis for planning surgical management. (orig.)

  14. Intravascular ultrasound and angiographic demonstration of left main stem thrombus-high-risk presentation in a young adult with anabolic steroid abuse.

    Science.gov (United States)

    Garg, Pankaj; Davis, Gershan; Wilson, John Ian; Sivananthan, Mohan

    2010-01-01

    We present a case of acute myocardial infarction in a young adult with a history of anabolic steroid abuse. On diagnostic coronary angiography and intravascular ultrasound, he was found to have a distal left main stem thrombus extending into the proximal left anterior descending artery and a large intermediate vessel. As he was hemodynamically stable and pain-free, he was managed conservatively with triple antiplatelet therapy (aspirin, clopidogrel, and abciximab). This was also to avoid the risk of 'wiring the vessel,' especially if there was underlying dissection. Repeat angiography a few weeks later showed complete thrombus resolution. This is the first reported case of extensive left main stem thrombus in a young patient with anabolic steroid abuse. Management of such cases is not straightforward and our case highlights one approach to both diagnosis and treatment.

  15. Morphological, molecular and functional differences of adult bone marrow- and adipose-derived stem cells isolated from rats of different ages

    Energy Technology Data Exchange (ETDEWEB)

    Mantovani, Cristina [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea (Sweden); Department of Surgical and Perioperative Science, Umea University, Umea (Sweden); Raimondo, Stefania [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy); Haneef, Maryam S. [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Geuna, Stefano [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy); Terenghi, Giorgio [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Shawcross, Susan G., E-mail: sue.shawcross@manchester.ac.uk [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Wiberg, Mikael [Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea (Sweden); Department of Surgical and Perioperative Science, Umea University, Umea (Sweden)

    2012-10-01

    Adult mesenchymal stem cells have self-renewal and multiple differentiation potentials, and play important roles in regenerative medicine. However, their use may be limited by senescence or age of the donor, leading to changes in stem cell functionality. We investigated morphological, molecular and functional differences between bone marrow-derived (MSC) and adipose-derived (ASC) stem cells isolated from neonatal, young and old rats compared to Schwann cells from the same animals. Immunocytochemistry, RT-PCR, proliferation assays, western blotting and transmission electron microscopy were used to investigate expression of senescence markers. Undifferentiated and differentiated ASC and MSC from animals of different ages expressed Notch-2 at similar levels; protein-38 and protein-53 were present in all groups of cells with a trend towards increased levels in cells from older animals compared to those from neonatal and young rats. Following co-culture with adult neuronal cells, dMSC and dASC from animals of all ages elicited robust neurite outgrowth. Mitotracker{sup Registered-Sign} staining was consistent with ultrastructural changes seen in the mitochondria of cells from old rats, indicative of senescence. In conclusion, this study showed that although the cells from aged animals expressed markers of senescence, aged MSC and ASC differentiated into SC-like cells still retain potential to support axon regeneration. -- Highlights: Black-Right-Pointing-Pointer Aged MSC and ASC differentiated into Schwann-like cells support axon regeneration. Black-Right-Pointing-Pointer p53 expression does not appreciably influence the biology of Schwann or stem cells. Black-Right-Pointing-Pointer Notch 2 expression was similar in cells derived from animals of different ages. Black-Right-Pointing-Pointer Proliferation rates of dMSC varied little over time or with animal age.

  16. Morphological, molecular and functional differences of adult bone marrow- and adipose-derived stem cells isolated from rats of different ages

    International Nuclear Information System (INIS)

    Mantovani, Cristina; Raimondo, Stefania; Haneef, Maryam S.; Geuna, Stefano; Terenghi, Giorgio; Shawcross, Susan G.; Wiberg, Mikael

    2012-01-01

    Adult mesenchymal stem cells have self-renewal and multiple differentiation potentials, and play important roles in regenerative medicine. However, their use may be limited by senescence or age of the donor, leading to changes in stem cell functionality. We investigated morphological, molecular and functional differences between bone marrow-derived (MSC) and adipose-derived (ASC) stem cells isolated from neonatal, young and old rats compared to Schwann cells from the same animals. Immunocytochemistry, RT-PCR, proliferation assays, western blotting and transmission electron microscopy were used to investigate expression of senescence markers. Undifferentiated and differentiated ASC and MSC from animals of different ages expressed Notch-2 at similar levels; protein-38 and protein-53 were present in all groups of cells with a trend towards increased levels in cells from older animals compared to those from neonatal and young rats. Following co-culture with adult neuronal cells, dMSC and dASC from animals of all ages elicited robust neurite outgrowth. Mitotracker ® staining was consistent with ultrastructural changes seen in the mitochondria of cells from old rats, indicative of senescence. In conclusion, this study showed that although the cells from aged animals expressed markers of senescence, aged MSC and ASC differentiated into SC-like cells still retain potential to support axon regeneration. -- Highlights: ► Aged MSC and ASC differentiated into Schwann-like cells support axon regeneration. ► p53 expression does not appreciably influence the biology of Schwann or stem cells. ► Notch 2 expression was similar in cells derived from animals of different ages. ► Proliferation rates of dMSC varied little over time or with animal age.

  17. Effect of Phenotypic Screening of Extracts and Fractions of Erythrophleum ivorense Leaf and Stem Bark on Immature and Adult Stages of Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Gertrude Kyere-Davies

    2018-01-01

    Full Text Available Schistosomiasis is a disease caused by a flatworm parasite that infects people in tropical and subtropical regions of Sub-Saharan Africa, South America, China, and Southeast Asia. The reliance on just one drug for current treatment emphasizes the need for new chemotherapeutic strategies. The aim of this study was to determine the phenotypic effects of extracts and fractions of leaf and stem bark of Erythrophleum ivorense (family Euphorbiaceae, a tree that grows in tropical parts of Africa, on two developmental stages of Schistosoma mansoni, namely, postinfective larvae (schistosomula or somules and adults. Methanol leaf and stem bark extracts of E. ivorense were successively fractionated with acetone, petroleum ether, ethyl acetate, and methanol. These fractions were then incubated with somules at 0.3125 to 100 μg/mL and with adults at 1.25 μg/mL. The acetone fractions of both the methanol leaf and bark of E. ivorense were most active against the somules whereas the petroleum ether fractions showed least activity. For adult parasites, the acetone fraction of methanol bark extract also elicited phenotypic changes. The data arising provide the first step in the discovery of new treatments for an endemic infectious disease using locally sourced African medicinal plants.

  18. Irradiation of the potential cancer stem cell niches in the adult brain improves progression-free survival of patients with malignant glioma

    International Nuclear Information System (INIS)

    Evers, Patrick; Lee, Percy P; DeMarco, John; Agazaryan, Nzhde; Sayre, James W; Selch, Michael; Pajonk, Frank

    2010-01-01

    Glioblastoma is the most common brain tumor in adults. The mechanisms leading to glioblastoma are not well understood but animal studies support that inactivation of tumor suppressor genes in neural stem cells (NSC) is required and sufficient to induce glial cancers. This suggests that the NSC niches in the brain may harbor cancer stem cells (CSCs), Thus providing novel therapy targets. We hypothesize that higher radiation doses to these NSC niches improve patient survival by eradicating CSCs. 55 adult patients with Grade 3 or Grade 4 glial cancer treated with radiotherapy at UCLA between February of 2003 and May of 2009 were included in this retrospective study. Using radiation planning software and patient radiological records, the SVZ and SGL were reconstructed for each of these patients and dosimetry data for these structures was calculated. Using Kaplan-Meier analysis we show that patients whose bilateral subventricular zone (SVZ) received greater than the median SVZ dose (= 43 Gy) had a significant improvement in progression-free survival if compared to patients who received less than the median dose (15.0 vs 7.2 months PFS; P = 0.028). Furthermore, a mean dose >43 Gy to the bilateral SVZ yielded a hazard ratio of 0.73 (P = 0.019). Importantly, similarly analyzing total prescription dose failed to illustrate a statistically significant impact. Our study leads us to hypothesize that in glioma targeted radiotherapy of the stem cell niches in the adult brain could yield significant benefits over radiotherapy of the primary tumor mass alone and that damage caused by smaller fractions of radiation maybe less efficiently detected by the DNA repair mechanisms in CSCs

  19. Quantitative analysis of DNA methylation at all human imprinted regions reveals preservation of epigenetic stability in adult somatic tissue

    Directory of Open Access Journals (Sweden)

    Woodfine Kathryn

    2011-01-01

    Full Text Available Abstract Background Genes subject to genomic imprinting are mono-allelically expressed in a parent-of-origin dependent manner. Each imprinted locus has at least one differentially methylated region (DMR which has allele specific DNA methylation and contributes to imprinted gene expression. Once DMRs are established, they are potentially able to withstand normal genome reprogramming events that occur during cell differentiation and germ-line DMRs are stably maintained throughout development. These DMRs, in addition to being either maternally or paternally methylated, have differences in whether methylation was acquired in the germ-line or post fertilization and are present in a variety of genomic locations with different Cytosine-phosphate guanine (CpG densities and CTCF binding capacities. We therefore examined the stability of maintenance of DNA methylation imprints and determined the normal baseline DNA methylation levels in several adult tissues for all imprinted genes. In order to do this, we first developed and validated 50 highly specific, quantitative DNA methylation pyrosequencing assays for the known DMRs associated with human imprinted genes. Results Remarkable stability of the DNA methylation imprint was observed in all germ-line DMRs and paternally methylated somatic DMRs (which maintained average methylation levels of between 35% - 65% in all somatic tissues, independent of gene expression. Maternally methylated somatic DMRs were found to have more variation with tissue specific methylation patterns. Most DMRs, however, showed some intra-individual variability for DNA methylation levels in peripheral blood, suggesting that more than one DMR needs to be examined in order to get an overall impression of the epigenetic stability in a tissue. The plasticity of DNA methylation at imprinted genes was examined in a panel of normal and cancer cell lines. All cell lines showed changes in DNA methylation, especially at the paternal germ-line

  20. Factors Released from Endothelial Cells Exposed to Flow Impact Adhesion, Proliferation, and Fate Choice in the Adult Neural Stem Cell Lineage.

    Science.gov (United States)

    Dumont, Courtney M; Piselli, Jennifer M; Kazi, Nadeem; Bowman, Evan; Li, Guoyun; Linhardt, Robert J; Temple, Sally; Dai, Guohao; Thompson, Deanna M

    2017-08-15

    The microvasculature within the neural stem cell (NSC) niche promotes self-renewal and regulates lineage progression. Previous work identified endothelial-produced soluble factors as key regulators of neural progenitor cell (NPC) fate and proliferation; however, endothelial cells (ECs) are sensitive to local hemodynamics, and the effect of this key physiological process has not been defined. In this study, we evaluated adult mouse NPC response to soluble factors isolated from static or dynamic (flow) EC cultures. Endothelial factors generated under dynamic conditions significantly increased neuronal differentiation, while those released under static conditions stimulated oligodendrocyte differentiation. Flow increases EC release of neurogenic factors and of heparin sulfate glycosaminoglycans that increase their bioactivity, likely underlying the enhanced neuronal differentiation. Additionally, endothelial factors, especially from static conditions, promoted adherent growth. Together, our data suggest that blood flow may impact proliferation, adhesion, and the neuron-glial fate choice of adult NPCs, with implications for diseases and aging that reduce flow.

  1. Wnts enhance neurotrophin-induced neuronal differentiation in adult bone-marrow-derived mesenchymal stem cells via canonical and noncanonical signaling pathways.

    Directory of Open Access Journals (Sweden)

    Hung-Li Tsai

    Full Text Available Wnts were previously shown to regulate the neurogenesis of neural stem or progenitor cells. Here, we explored the underlying molecular mechanisms through which Wnt signaling regulates neurotrophins (NTs in the NT-induced neuronal differentiation of human mesenchymal stem cells (hMSCs. NTs can increase the expression of Wnt1 and Wnt7a in hMSCs. However, only Wnt7a enables the expression of synapsin-1, a synaptic marker in mature neurons, to be induced and triggers the formation of cholinergic and dopaminergic neurons. Human recombinant (hrWnt7a and general neuron makers were positively correlated in a dose- and time-dependent manner. In addition, the expression of synaptic markers and neurites was induced by Wnt7a and lithium, a glycogen synthase kinase-3β inhibitor, in the NT-induced hMSCs via the canonical/β-catenin pathway, but was inhibited by Wnt inhibitors and frizzled-5 (Frz5 blocking antibodies. In addition, hrWnt7a triggered the formation of cholinergic and dopaminergic neurons via the non-canonical/c-jun N-terminal kinase (JNK pathway, and the formation of these neurons was inhibited by a JNK inhibitor and Frz9 blocking antibodies. In conclusion, hrWnt7a enhances the synthesis of synapse and facilitates neuronal differentiation in hMSCS through various Frz receptors. These mechanisms may be employed widely in the transdifferentiation of other adult stem cells.

  2. Pathways into STEM among low-income, urban immigrant emergent bilingual/multilingual young adults: Opportunity, access, and persistence

    Science.gov (United States)

    Heyman, Jeremy Benjamin

    This project builds upon the author's multi-year critical ethnographic study of urban immigrant students and their trajectories into STEM (science, technology, engineering, or mathematics) from high school through their transition to college. At its core, this study investigates the paths of over three dozen newcomer immigrant English language learner students in high-poverty urban neighborhoods who are not generally considered "legitimate contenders" for Bachelor's degrees in STEM fields on the basis of such characteristics as test scores, high school and prior preparation, and age. The students are followed through their high school experiences, their transition to college, and through their current progress in college, with explicit attention paid to key mediating experiences and relationships in and especially outside of the classroom that were associated with their toward persistence and success. Thick description and analysis of the students and their experiences, among those who persisted as well as the minority who switched out of STEM majors, helps to demonstrate a proof-of-concept of these students' ability to succeed while painting a comprehensive picture of their march forward to degrees in STEM fields against a backdrop of economic, linguistic, and other barriers to entry and success. Using a framework of social and capital and resilience theories, this work has uncovered a number of themes and factors that will help educators to better understand the evolution of these traditionally marginalized students' STEM-related interests, skills, and career plans. The findings center around students' exposure to research internships and other STEM enrichment and outreach experiences, long-term mentoring and other key relationships, and integration of STEM and college access efforts in setting them up for a successful transition to college, as well as an emphasis on the importance of students' calling upon their own resilience and other strengths and prior

  3. Angiotensin-converting enzyme (CD143) marks hematopoietic stem cells in human embryonic, fetal, and adult hematopoietic tissues

    NARCIS (Netherlands)

    Jokubaitis, Vanta J.; Sinka, Lidia; Driessen, Rebecca; Whitty, Genevieve; Haylock, David N.; Bertoncello, Ivan; Smith, Ian; Peault, Bruno; Tavian, Manuela; Simmons, Paul J.

    2008-01-01

    Previous studies revealed that mAb BB9 reacts with a subset of CD34(+) human BM cells with hematopoietic stem cell (HSC) characteristics. Here we map B89 expression throughout hernatopoietic development and show that the earliest definitive HSCs that arise at the ventral wall of the aorta and

  4. Nop2 is expressed during proliferation of neural stem cells and in adult mouse and human brain

    Czech Academy of Sciences Publication Activity Database

    Kosi, N.; Alic, I.; Kolacevic, M.; Vrsaljko, N.; Milosevic, N.J.; Sobol, Margaryta; Philimonenko, Anatoly; Hozák, Pavel; Gajovic, S.; Pochet, R.; Mitrecic, D.

    2015-01-01

    Roč. 1597, FEB 9 (2015), s. 65-76 ISSN 1872-6240 R&D Projects: GA TA ČR(CZ) TE01020118; GA MPO FR-TI3/588 Institutional support: RVO:68378050 Keywords : Nop2 * Brain * Stem cells * Stroke * Nucleolus * Cell cycle Subject RIV: EB - Genetics ; Molecular Biology

  5. Nop2 is expressed during proliferation of neural stem cells and in adult mouse and human brain

    Czech Academy of Sciences Publication Activity Database

    Kosi, N.; Alic, I.; Kolačevic, M.; Vrsaljko, N.; Miloševic, N.J.; Sobol, Margaryta; Filimonenko, Anatolij; Hozák, Pavel; Gajovic, S.; Pochet, R.; Mitrečic, D.

    2015-01-01

    Roč. 1597, February (2015), s. 65-76 ISSN 1872-6240 R&D Projects: GA TA ČR(CZ) TE01020118; GA MPO FR-TI3/588 Institutional support: RVO:68378050 Keywords : Nop2 * Brain * Stem cells * Stroke Subject RIV: EB - Genetics ; Molecular Biology

  6. Treatment of radioinduced skin burns by adult stem cells;Traitement des brulures cutanees radio-induites par cellules souches adultes

    Energy Technology Data Exchange (ETDEWEB)

    Lataillade, J.J.; Prat, M. [Hopital Militaire Percy, Centre de Transfusion Sanguine des Armees, Dept. Recherches et Therapies Cellulaires, 92 - Clamart (France); Gourmelon, P. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Fontenay-aux-Roses (France); Bey, E. [Hopital Militaire Percy, Service de Chirurgie Plastique, 92 - Clamart (France)

    2009-12-15

    In the area of skin injuries caused by ionizing radiations; the recent opportunity give us the the possibility to manage victims of radiation accidents with skin acute symptoms of irradiation. The approach of cell therapy developed for these patients could be in a second time, used for other types of injuries as thermal burns and the injuries linked to overexposure in radiotherapy. In spite of the diversity of approaches of allogeneic and autologous transplantation, the prognosis of deep and extended radioinduced burns is not completely satisfying because of inflammatory recurrences, origin of graft failures. The stem cells have been used in association. The stem cells were got from sampling of autologous bone marrow after an expansion in vitro from 15 to 17 days. The cultures were realised in medium with 8% of platelet lysate (clinical grade). The cells have been given by injection in complement of epidermis auto graft. A spectacular effect was noticed the day after the injection, but disappearing in some days encouraging to realize supplementary injections. An effect of the quickness and the quality of the graft success is appeared significant too. no necrosis recurrence for the patients after four years for the first one of them. We think that the stem cells participate to the local control of inflammation. (N.C.)

  7. DMRT1 Is Required for Mouse Spermatogonial Stem Cell Maintenance and Replenishment.

    Science.gov (United States)

    Zhang, Teng; Oatley, Jon; Bardwell, Vivian J; Zarkower, David

    2016-09-01

    Male mammals produce sperm for most of postnatal life and therefore require a robust germ line stem cell system, with precise balance between self-renewal and differentiation. Prior work established doublesex- and mab-3-related transcription factor 1 (Dmrt1) as a conserved transcriptional regulator of male sexual differentiation. Here we investigate the role of Dmrt1 in mouse spermatogonial stem cell (SSC) homeostasis. We find that Dmrt1 maintains SSCs during steady state spermatogenesis, where it regulates expression of Plzf, another transcription factor required for SSC maintenance. We also find that Dmrt1 is required for recovery of spermatogenesis after germ cell depletion. Committed progenitor cells expressing Ngn3 normally do not contribute to SSCs marked by the Id4-Gfp transgene, but do so when spermatogonia are chemically depleted using busulfan. Removal of Dmrt1 from Ngn3-positive germ cells blocks the replenishment of Id4-GFP-positive SSCs and recovery of spermatogenesis after busulfan treatment. Our data therefore reveal that Dmrt1 supports SSC maintenance in two ways: allowing SSCs to remain in the stem cell pool under normal conditions; and enabling progenitor cells to help restore the stem cell pool after germ cell depletion.

  8. Graft-Versus-Host Disease in Adolescents and Young Adults (15-24 Years Old) After Allogeneic Hematopoietic Stem Cell Transplantation for Acute Leukemia in First Complete Remission.

    Science.gov (United States)

    Vignon, Marguerite; Andreoli, Annalisa; Dhédin, Nathalie; Lengliné, Etienne; Masson, Emeline; Robin, Marie; Granier, Clémence; Larghero, Jérôme; Schlageter, Marie-Hélène; de Latour, Régis Peffault; Socié, Gérard; Boissel, Nicolas

    2017-06-01

    Adolescents and young adults (AYAs) with cancer are a unique group of patients in terms of disease incidence and biology, outcome, and psychosocial needs. This study aims to correlate the risk of graft-versus-host disease (GvHD) and age in a population of children and young adults with acute leukemia undergoing hematopoietic stem cell transplantation (HSCT) in first complete remission (CR). We analyzed the outcome of 153 consecutive children (<15 years), AYAs (15-24 years), and adults (25-35 years) with lymphoblastic or myeloid acute leukemia in first CR who underwent HSCT with matched donors after myeloablative conditioning. GvHD prophylaxis was methotrexate and cyclosporine A (CsA) in all patients. The cumulative incidence of grade II-IV acute GvHD (aGvHD) was significantly higher in AYA patients than in children (subdistribution hazard ratio (SHR), 2.04, p = 0.005) or adults (SHR 1.59, p = 0.048). Both gut and skin aGvHD occurred more frequently in AYA patients. Increasing CsA blood levels with age could not fully account for this difference. No difference in terms of grade III-IV aGvHD was observed. Chronic GvHD was more frequent in AYAs (SHR 2.81, p = 0.007) and adults (SHR 2.31, p = 0.033) than in children. No difference in terms of nonrelated mortality and overall survival was observed among the age subgroups. Since GvHD occurrence is strongly correlated to quality of life, specific attention should be paid to AYAs undergoing HSCT. Further studies should investigate the reasons for the excess of GvHD observed in this population.

  9. Protease-activated receptor-1 negatively regulates proliferation of neural stem/progenitor cells derived from the hippocampal dentate gyrus of the adult mouse

    Directory of Open Access Journals (Sweden)

    Masayuki Tanaka

    2016-07-01

    Full Text Available Thrombin-activated protease-activated receptor (PAR-1 regulates the proliferation of neural cells following brain injury. To elucidate the involvement of PAR-1 in the neurogenesis that occurs in the adult hippocampus, we examined whether PAR-1 regulated the proliferation of neural stem/progenitor cells (NPCs derived from the murine hippocampal dentate gyrus. NPC cultures expressed PAR-1 protein and mRNA encoding all subtypes of PAR. Direct exposure of the cells to thrombin dramatically attenuated the cell proliferation without causing cell damage. This thrombin-induced attenuation was almost completely abolished by the PAR antagonist RWJ 56110, as well as by dabigatran and 4-(2-aminoethylbenzenesulfonyl fluoride (AEBSF, which are selective and non-selective thrombin inhibitors, respectively. Expectedly, the PAR-1 agonist peptide (AP SFLLR-NH2 also attenuated the cell proliferation. The cell proliferation was not affected by the PAR-1 negative control peptide RLLFT-NH2, which is an inactive peptide for PAR-1. Independently, we determined the effect of in vivo treatment with AEBSF or AP on hippocampal neurogenesis in the adult mouse. The administration of AEBSF, but not that of AP, significantly increased the number of newly-generated cells in the hippocampal subgranular zone. These data suggest that PAR-1 negatively regulated adult neurogenesis in the hippocampus by inhibiting the proliferative activity of the NPCs.

  10. In vivo fate analysis reveals the multipotent and self-renewal capacities of Sox2+ neural stem cells in the adult hippocampus

    Science.gov (United States)

    Suh, Hoonkyo; Consiglio, Antonella; Ray, Jasodhara; Sawai, Toru; D'Amour, Kevin A.; Gage, Fred H.

    2007-01-01

    Summary To characterize the properties of adult neural stem cells (NSCs), we generated and analyzed Sox2-GFP transgenic mice. Sox2-GFP cells in the subgranular zone (SGZ) express markers specific for progenitors, but they represent two morphologically distinct populations that differ in proliferation levels. Lentivirus- and retrovirus-mediated fate tracing studies showed that Sox2+ cells in the SGZ have potential to give rise to neurons and astrocytes, revealing their multipotency at the population as well as a single cell level. More interestingly, a subpopulation of Sox2+ cells gives rise to cells that retain Sox2, highlighting Sox2+ cells as a primary source for adult NSCs. In response to mitotic signals, increased proliferation of Sox2+ cells is coupled with the generation of Sox2+ NSCs as well as neuronal precursors. An asymmetric contribution of Sox2+ NSCs may play an important role in maintaining the constant size of the NSC pool and producing newly born neurons during adult neurogenesis. PMID:18371391

  11. Establishment of a Novel Lingual Organoid Culture System: Generation of Organoids Having Mature Keratinized Epithelium from Adult Epithelial Stem Cells

    Science.gov (United States)

    Hisha, Hiroko; Tanaka, Toshihiro; Kanno, Shohei; Tokuyama, Yoko; Komai, Yoshihiro; Ohe, Shuichi; Yanai, Hirotsugu; Omachi, Taichi; Ueno, Hiroo

    2013-11-01

    Despite the strong need for the establishment of a lingual epithelial cell culture system, a simple and convenient culture method has not yet been established. Here, we report the establishment of a novel lingual epithelium organoid culture system using a three-dimensional matrix and growth factors. Histological analyses showed that the generated organoids had both a stratified squamous epithelial cell layer and a stratum corneum. Very recently, we showed via a multicolor lineage tracing method that Bmi1-positive stem cells exist at the base of the epithelial basal layer in the interpapillary pit. Using our new culture system, we found that organoids could be generated by single Bmi1-positive stem cells and that in the established organoids, multiple Bmi1-positive stem cells were generated at the outermost layer. Moreover, we observed that organoids harvested at an early point in culture could be engrafted and maturate in the tongue of recipient mice and that the organoids generated from carcinogen-treated mice had an abnormal morphology. Thus, this culture system presents valuable settings for studying not only the regulatory mechanisms of lingual epithelium but also lingual regeneration and carcinogenesis.

  12. Comparative Evaluation of Human Mesenchymal Stem Cells of Fetal (Wharton's Jelly and Adult (Adipose Tissue Origin during Prolonged In Vitro Expansion: Considerations for Cytotherapy

    Directory of Open Access Journals (Sweden)

    I. Christodoulou

    2013-01-01

    Full Text Available Mesenchymal stem cells (MSCs are somatic cells with a dual capacity for self-renewal and differentiation, and diverse therapeutic applicability, both experimentally and in the clinic. These cells can be isolated from various human tissues that may differ anatomically or developmentally with relative ease. Heterogeneity due to biological origin or in vitro manipulation is, nevertheless, considerable and may equate to differences in qualitative and quantitative characteristics which can prove crucial for successful therapeutic use. With this in mind, in the present study we have evaluated the proliferation kinetics and phenotypic characteristics of MSCs derived from two abundant sources, that is, fetal umbilical cord matrix (Wharton's jelly and adult adipose tissue (termed WJSC and ADSC, resp. during prolonged in vitro expansion, a process necessary for obtaining cell numbers sufficient for clinical application. Our results show that WJSC are derived with relatively high efficiency and bear a substantially increased proliferation capacity whilst largely sustaining the expression of typical immunophenotypic markers, whereas ADSC exhibit a reduced proliferation potential showing typical signs of senescence at an early stage. By combining kinetic with phenotypic data we identify culture thresholds up to which both cell types maintain their stem properties, and we discuss the practical implications of their differences.

  13. How necessary is the vasculature in the life of neural stem and progenitor cells? Evidence from evolution, development and the adult nervous system.

    Directory of Open Access Journals (Sweden)

    CHRISTOS eKOUTSAKIS

    2016-02-01

    Full Text Available Augmenting evidence suggests that such is the functional dependence of neural stem cells (NSCs on the vasculature that they normally reside in perivascular niches. Two examples are the neurovascular and the oligovascular niches of the adult brain, specialized microenvironments where NSCs or oligodendrocyte progenitor cells survive and remain mitotically active in close proximity to blood vessels. In addition, the often observed co-ordination of angiogenesis and neurogenesis led to these processes being described as coupled. Here, we adopt an evo-devo approach to argue that some stages in the life of a NSC, such as specification and commitment, are independent of the vasculature, while stages such as proliferation and migration are largely dependent on blood vessels. We also explore available evidence on the possible involvement of the vasculature in other phenomena such as the diversification of NSCs during evolution and we provide original data on the senescence of NSCs in the subependymal zone stem cell niche. Finally, we will comment on the other side of the story; on how much is the vasculature dependent on NSCs and their progeny.

  14. PGE2 maintains self-renewal of human adult stem cells via EP2-mediated autocrine signaling and its production is regulated by cell-to-cell contact.

    Science.gov (United States)

    Lee, Byung-Chul; Kim, Hyung-Sik; Shin, Tae-Hoon; Kang, Insung; Lee, Jin Young; Kim, Jae-Jun; Kang, Hyun Kyoung; Seo, Yoojin; Lee, Seunghee; Yu, Kyung-Rok; Choi, Soon Won; Kang, Kyung-Sun

    2016-05-27

    Mesenchymal stem cells (MSCs) possess unique immunomodulatory abilities. Many studies have elucidated the clinical efficacy and underlying mechanisms of MSCs in immune disorders. Although immunoregulatory factors, such as Prostaglandin E2 (PGE2), and their mechanisms of action on immune cells have been revealed, their effects on MSCs and regulation of their production by the culture environment are less clear. Therefore, we investigated the autocrine effect of PGE2 on human adult stem cells from cord blood or adipose tissue, and the regulation of its production by cell-to-cell contact, followed by the determination of its immunomodulatory properties. MSCs were treated with specific inhibitors to suppress PGE2 secretion, and proliferation was assessed. PGE2 exerted an autocrine regulatory function in MSCs by triggering E-Prostanoid (EP) 2 receptor. Inhibiting PGE2 production led to growth arrest, whereas addition of MSC-derived PGE2 restored proliferation. The level of PGE2 production from an equivalent number of MSCs was down-regulated via gap junctional intercellular communication. This cell contact-mediated decrease in PGE2 secretion down-regulated the suppressive effect of MSCs on immune cells. In conclusion, PGE2 produced by MSCs contributes to maintenance of self-renewal capacity through EP2 in an autocrine manner, and PGE2 secretion is down-regulated by cell-to-cell contact, attenuating its immunomodulatory potency.

  15. Gene expression profiling and secretome analysis differentiate adult-derived human liver stem/progenitor cells and human hepatic stellate cells.

    Directory of Open Access Journals (Sweden)

    Silvia Berardis

    Full Text Available Adult-derived human liver stem/progenitor cells (ADHLSC are obtained after primary culture of the liver parenchymal fraction. The cells are of fibroblastic morphology and exhibit a hepato-mesenchymal phenotype. Hepatic stellate cells (HSC derived from the liver non-parenchymal fraction, present a comparable morphology as ADHLSC. Because both ADHLSC and HSC are described as liver stem/progenitor cells, we strived to extensively compare both cell populations at different levels and to propose tools demonstrating their singularity. ADHLSC and HSC were isolated from the liver of four different donors, expanded in vitro and followed from passage 5 until passage 11. Cell characterization was performed using immunocytochemistry, western blotting, flow cytometry, and gene microarray analyses. The secretion profile of the cells was evaluated using Elisa and multiplex Luminex assays. Both cell types expressed α-smooth muscle actin, vimentin, fibronectin, CD73 and CD90 in accordance with their mesenchymal origin. Microarray analysis revealed significant differences in gene expression profiles. HSC present high expression levels of neuronal markers as well as cytokeratins. Such differences were confirmed using immunocytochemistry and western blotting assays. Furthermore, both cell types displayed distinct secretion profiles as ADHLSC highly secreted cytokines of therapeutic and immuno-modulatory importance, like HGF, interferon-γ and IL-10. Our study demonstrates that ADHLSC and HSC are distinct liver fibroblastic cell populations exhibiting significant different expression and secretion profiles.

  16. In vitro effects of aqueous extract from Maytenus senegalensis (Lam.) Exell stem bark on egg hatching, larval migration and adult worms of Haemonchus contortus.

    Science.gov (United States)

    Zangueu, Calvin Bogning; Olounlade, Abiodoun Pascal; Ossokomack, Marlyse; Djouatsa, Yolande Noelle Nangue; Alowanou, Goue Géorcelin; Azebaze, Anatole Guy Blaise; Llorent-Martínez, Eulogio José; de Córdova, Maria Luisa Fernández; Dongmo, Alain Bertrand; Hounzangbe-Adote, Mawulé Sylvie

    2018-05-02

    Maytenus senegalensis is a common shrub which is scattered in tropical Africa. Different parts of this plant have been reported to be useful in traditional medicine against gastrointestinal disorders and intestinal worms. This study evaluated the anthelmintic activity of the aqueous stem bark extract of M. senegalensis using egg hatch assay (EHA), larval migration inhibition assay (LMIA) and adult worms' motility inhibition assay (AMIA). On EHA, the extract concentrations tested resulted in a significant (p  50%). These in vitro results suggest the presence of some anthelmintic properties in M. senegalensis extract, which is traditionally used by small farmers in west and central Africa. These effects may be due to the flavonoids and proanthocyanidins present in the extract and need to be studied under in vivo conditions.

  17. Cost utility analysis of reduced intensity hematopoietic stem cell transplantation in adolescence and young adult with severe thalassemia compared to hypertransfusion and iron chelation program.

    Science.gov (United States)

    Sruamsiri, Rosarin; Chaiyakunapruk, Nathorn; Pakakasama, Samart; Sirireung, Somtawin; Sripaiboonkij, Nintita; Bunworasate, Udomsak; Hongeng, Suradej

    2013-02-05

    Hematopoieticic stem cell transplantation is the only therapeutic option that can cure thalassemia disease. Reduced intensity hematopoietic stem cell transplantation (RI-HSCT) has demonstrated a high cure rate with minimal complications compared to other options. Because RI-HSCT is very costly, economic justification for its value is needed. This study aimed to estimate the cost-utility of RI-HSCT compared with blood transfusions combined with iron chelating therapy (BT-ICT) for adolescent and young adult with severe thalassemia in Thailand. A Markov model was used to estimate the relevant costs and health outcomes over the patients' lifetimes using a societal perspective. All future costs and outcomes were discounted at a rate of 3% per annum. The efficacy of RI-HSCT was based a clinical trial including a total of 18 thalassemia patients. Utility values were derived directly from all patients using EQ-5D and SF-6D. Primary outcomes of interest were lifetime costs, quality adjusted life-years (QALYs) gained, and the incremental cost-effectiveness ratio (ICER) in US ($) per QALY gained. One-way and probabilistic sensitivity analyses (PSA) were conducted to investigate the effect of parameter uncertainty. In base case analysis, the RI-HSCT group had a better clinical outcomes and higher lifetime costs. The incremental cost per QALY gained was US $3,236 per QALY. The acceptability curve showed that the probability of RI-HSCT being cost-effective was 71% at the willingness to pay of 1 time of Thai Gross domestic product per capita (GDP per capita), approximately US $4,210 per QALY gained. The most sensitive parameter was utility of severe thalassemia patients without cardiac complication patients. At a societal willingness to pay of 1 GDP per capita, RI-HSCT was a cost-effective treatment for adolescent and young adult with severe thalassemia in Thailand compared to BT-ICT.

  18. Cost utility analysis of reduced intensity hematopoietic stem cell transplantation in adolescence and young adult with severe thalassemia compared to hypertransfusion and iron chelation program

    Directory of Open Access Journals (Sweden)

    Sruamsiri Rosarin

    2013-02-01

    Full Text Available Abstract Background Hematopoieticic stem cell transplantation is the only therapeutic option that can cure thalassemia disease. Reduced intensity hematopoietic stem cell transplantation (RI-HSCT has demonstrated a high cure rate with minimal complications compared to other options. Because RI-HSCT is very costly, economic justification for its value is needed. This study aimed to estimate the cost-utility of RI-HSCT compared with blood transfusions combined with iron chelating therapy (BT-ICT for adolescent and young adult with severe thalassemia in Thailand. Methods A Markov model was used to estimate the relevant costs and health outcomes over the patients’ lifetimes using a societal perspective. All future costs and outcomes were discounted at a rate of 3% per annum. The efficacy of RI-HSCT was based a clinical trial including a total of 18 thalassemia patients. Utility values were derived directly from all patients using EQ-5D and SF-6D. Primary outcomes of interest were lifetime costs, quality adjusted life-years (QALYs gained, and the incremental cost-effectiveness ratio (ICER in US ($ per QALY gained. One-way and probabilistic sensitivity analyses (PSA were conducted to investigate the effect of parameter uncertainty. Results In base case analysis, the RI-HSCT group had a better clinical outcomes and higher lifetime costs. The incremental cost per QALY gained was US $ 3,236 per QALY. The acceptability curve showed that the probability of RI-HSCT being cost-effective was 71% at the willingness to pay of 1 time of Thai Gross domestic product per capita (GDP per capita, approximately US $ 4,210 per QALY gained. The most sensitive parameter was utility of severe thalassemia patients without cardiac complication patients. Conclusion At a societal willingness to pay of 1 GDP per capita, RI-HSCT was a cost-effective treatment for adolescent and young adult with severe thalassemia in Thailand compared to BT-ICT.

  19. Variation of some wood macroscopic properties along the stem of Acacia melanoxylon R. Br. adult trees in Portugal

    Directory of Open Access Journals (Sweden)

    A. Santos

    2013-12-01

    Full Text Available Aim of the study: The aim of the study is to assess the variation of pith eccentricity, heartwood proportion, latewood percentage and basic wood density along the stem of 45-year-old A. melanoxylon trees collected in four sites of Portugal, and investigate the eventual relationship between these variables.Area of study: Sites covering littoral north, mid interior north and centre interior of Portugal.Materials and methods: Four sites and five trees per site were selected in the Acacia melanoxylon Portuguese forest.One wood sample at each of six height levels per tree was collected in order to evaluate its basic density, pith eccentricity, heartwood and latewood proportions.Main results: The high variability of the wood macroscopic properties among trees from the same site regarding to the variation of the corresponding average properties along the stem is a key characteristic of the experimental data.As a consequence, a multiple linear regression model tested was not able to properly explain the wood basic density variation of the 120 wood samples analysed. In spite of this, the following trends could be recognized: (i excluding the base level, wood basic density moderately increased with tree level; (ii latewood proportion followed similar behaviour; (iii pith eccentricity was low; (iv heartwood proportion decreased markedly with tree height, from 70% at the base to 7% at the top.Research highlights: The high basic density, the relatively low variability along the stem and the low pith eccentricity enable us to anticipate good performance as raw material for the wood industry.Key words: Acacia melanoxylon; basic density; earlywood; latewood; heartwood; sapwood; pith eccentricity.

  20. Tumor necrosis factor α triggers proliferation of adult neural stem cells via IKK/NF-κB signaling

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    Kaltschmidt Christian

    2006-09-01

    Full Text Available Abstract Background Brain inflammation has been recognized as a complex phenomenon with numerous related aspects. In addition to the very well-described neurodegenerative effect of inflammation, several studies suggest that inflammatory signals exert a potentially positive influence on neural stem cell proliferation, migration and differentiation. Tumor necrosis factor alpha (TNF-α is one of the best-characterized mediators of inflammation. To date, conclusions about the action of TNF on neural stem or progenitor cells (NSCs, NPCs have been conflicting. TNF seems to activate NSC proliferation and to inhibit their differentiation into NPCs. The purpose of the present study was to analyze the molecular signal transduction mechanisms induced by TNF and resulting in NSC proliferation. Results Here we describe for the first time the TNF-mediated signal transduction cascade in neural stem cells (NSCs that results in increased proliferation. Moreover, we demonstrate IKK-α/β-dependent proliferation and markedly up-regulated cyclin D1 expression after TNF treatment. The significant increase in proliferation in TNF-treated cells was indicated by increased neurosphere volume, increased bromodeoxyuridin (BrdU incorporation and a higher total cell number. Furthermore, TNF strongly activated nuclear factor-kappa B (NF-κB as measured by reporter gene assays and by an activity-specific antibody. Proliferation of control and TNF-treated NSCs was strongly inhibited by expression of the NF-κB super-repressor IκB-AA1. Pharmacological blockade of IκB ubiquitin ligase activity led to comparable decreases in NF-κB activity and proliferation. In addition, IKK-β gene product knock-down via siRNA led to diminished NF-κB activity, attenuated cyclin D1 expression and finally decreased proliferation. In contrast, TGFβ-activated kinase 1 (TAK-1 is partially dispensable for TNF-mediated and endogenous proliferation. Understanding stem cell proliferation is crucial

  1. In Vitro T-Cell Generation From Adult, Embryonic, and Induced Pluripotent Stem Cells: Many Roads to One Destination.

    Science.gov (United States)

    Smith, Michelle J; Webber, Beau R; Mohtashami, Mahmood; Stefanski, Heather E; Zúñiga-Pflücker, Juan Carlos; Blazar, Bruce R

    2015-11-01

    T lymphocytes are critical mediators of the adaptive immune system and have the capacity to serve as therapeutic agents in the areas of transplant and cancer immunotherapy. While T cells can be isolated and expanded from patients, T cells derived in vitro from both hematopoietic stem/progenitor cells (HSPCs) and human pluripotent stem cells (hPSCs) offer great potential advantages in generating a self-renewing source of T cells that can be readily genetically modified. T-cell differentiation in vivo is a complex process requiring tightly regulated signals; providing the correct signals in vitro to induce T-cell lineage commitment followed by their development into mature, functional, single positive T cells, is similarly complex. In this review, we discuss current methods for the in vitro derivation of T cells from murine and human HSPCs and hPSCs that use feeder-cell and feeder-cell-free systems. Furthermore, we explore their potential for adoption for use in T-cell-based therapies. © 2015 AlphaMed Press.

  2. Stem Cell: Past, Present and Future- A Review Article | Avasthi ...

    African Journals Online (AJOL)

    Stem cells are basic cells of all multicellular organisms having the potency to differentiate into wide range of adult cells. Self renewal and totipotency are characteristic of stem cells. Though totipotency is shown by very early embryonic stem cells, the adult stem cells possess multipotency and differential plasticity which can ...

  3. Combination of cytogenetic classification and MRD status correlates with outcome of autologous versus allogeneic stem cell transplantation in adults with primary acute myeloid leukemia in first remission.

    Science.gov (United States)

    Yao, Jianfeng; Zhang, Guixin; Liang, Chen; Li, Gang; Chen, Xin; Ma, Qiaoling; Zhai, Weihua; Yang, Donglin; He, Yi; Jiang, Erlie; Feng, Sizhou; Han, Mingzhe

    2017-04-01

    Both autologous and allogeneic stem cell transplantation (auto- and allo-SCT) are treatment choice for adults with acute myeloid leukemia (AML) after complete remission (CR). However, the decision-making remains controversial in some situations. To figure out the treatment choice, we retrospectively investigated 172 consecutive patients with primary AML who received auto- (n=46) or allo-SCT (n=126) from a single transplant center. Auto- and allo-SCT group demonstrated comparable overall survival (OS) and disease-free survival (DFS) (P=0.616, P=0.559, respectively). Cytogenetic classification and minimal residual disease (MRD) after one course of consolidation were identified as independent risk factors for DFS (hazard ratio (HR), 1.800; 95% CI, 1.172-2.763; P=0.007; HR, 2.042; 95%CI, 1.003-4.154; P=0.049; respectively). We subsequently found that auto- and allo-SCT offered comparable DFS to patients with favorable or intermediate risk and were tested MRD neg after one course of consolidation (P=0.270) otherwise auto-SCT were inferior due to increased risk of leukemia relapse. Our study indicated that the combination of cytogenetic classification and MRD monitoring correlated with outcome of auto- versus allo-SCT and might help the choice between the two types of SCT for adults with primary AML, which is of significance for patients with expected intermediate prognosis in the current scenario. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Thyroid hormone participates in the regulation of neural stem cells and oligodendrocyte precursor cells in the central nervous system of adult rat.

    Science.gov (United States)

    Fernandez, M; Pirondi, S; Manservigi, M; Giardino, L; Calzà, L

    2004-10-01

    Oligodendrocyte development and myelination are under thyroid hormone control. In this study we analysed the effects of chronic manipulation of thyroid status on the expression of a wide spectrum of oligodendrocyte precursor cells (OPCs) markers and myelin basic protein (MBP) in the subventricular zone (SVZ), olfactory bulb and optic nerve, and on neural stem cell (NSC) lineage in adult rats. Hypo- and hyperthyroidism were induced in male rats, by propyl-thio-uracil (PTU) and L-thyroxin (T4) treatment, respectively. Hypothyroidism increased and hyperthyroidism downregulated proliferation in the SVZ and olfactory bulb (Ki67 immunohistochemistry and Western blotting, bromodeoxyuridine uptake). Platelet-derived growth factor receptor alpha (PDGFalpha-R) and MBP mRNA levels decreased in the optic nerve of hypothyroid rats; the same also occurred at the level of MBP protein. Hyperthyroidism slightly upregulates selected markers such as NG2 in the olfactory bulb. The lineage of cells derived from primary cultures of NSC prepared from the forebrain of adult hypo- and hyperthyroid also differs from those derived from control animals. Although no difference of in vitro proliferation of NSCs was observed in the presence of epidermal growth factor, maturation of oligodendrocytes (defined by process number and length) was enhanced in hyperthyroidism, suggesting a more mature state than in control animals. This difference was even greater when compared with the hypothyroid group, the morphology of which suggested a delay in differentiation. These results indicate that thyroid hormone affects NSC and OPC proliferation and maturation also in adulthood.

  5. The Satellite Cell in Male and Female, Developing and Adult Mouse Muscle: Distinct Stem Cells for Growth and Regeneration

    Science.gov (United States)

    Neal, Alice; Boldrin, Luisa; Morgan, Jennifer Elizabeth

    2012-01-01

    Satellite cells are myogenic cells found between the basal lamina and the sarcolemma of the muscle fibre. Satellite cells are the source of new myofibres; as such, satellite cell transplantation holds promise as a treatment for muscular dystrophies. We have investigated age and sex differences between mouse satellite cells in vitro and assessed the importance of these factors as mediators of donor cell engraftment in an in vivo model of satellite cell transplantation. We found that satellite cell numbers are increased in growing compared to adult and in male compared to female adult mice. We saw no difference in the expression of the myogenic regulatory factors between male and female mice, but distinct profiles were observed according to developmental stage. We show that, in contrast to adult mice, the majority of satellite cells from two week old mice are proliferating to facilitate myofibre growth; however a small proportion of these cells are quiescent and not contributing to this growth programme. Despite observed changes in satellite cell populations, there is no difference in engraftment efficiency either between satellite cells derived from adult or pre-weaned donor mice, male or female donor cells, or between male and female host muscle environments. We suggest there exist two distinct satellite cell populations: one for muscle growth and maintenance and one for muscle regeneration. PMID:22662253

  6. In vitro cytotoxicity of nanoparticles in mammalian germline stem cells.

    Science.gov (United States)

    Braydich-Stolle, Laura; Hussain, Saber; Schlager, John J; Hofmann, Marie-Claude

    2005-12-01

    Gametogenesis is a complex biological process that is particularly sensitive to environmental insults such as chemicals. Many chemicals have a negative impact on the germline, either by directly affecting the germ cells, or indirectly through their action on the somatic nursing cells. Ultimately, these effects can inhibit fertility, and they may have negative consequences for the development of the offspring. Recently, nanomaterials such as nanotubes, nanowires, fullerene derivatives (buckyballs), and quantum dots have received enormous national attention in the creation of new types of analytical tools for biotechnology and the life sciences. Despite the wide application of nanomaterials, there is a serious lack of information concerning their impact on human health and the environment. Thus, there are limited studies available on toxicity of nanoparticles for risk assessment of nanomaterials. The purpose of this study was to assess the suitability of a mouse spermatogonial stem cell line as a model to assess nanotoxicity in the male germline in vitro. The effects of different types of nanoparticles on these cells were evaluated by light microscopy, and by cell proliferation and standard cytotoxicity assays. Our results demonstrate a concentration-dependent toxicity for all types of particles tested, whereas the corresponding soluble salts had no significant effect. Silver nanoparticles were the most toxic while molybdenum trioxide (MoO(3)) nanoparticles were the least toxic. Our results suggest that this cell line provides a valuable model with which to assess the cytotoxicity of nanoparticles in the germ line in vitro.

  7. Characterization and comparison of osteoblasts derived from mouse embryonic stem cells and induced pluripotent stem cells

    NARCIS (Netherlands)

    Ma, Ming San; Kannan, Vishnu; de Vries, Anneriek E; Czepiel, Marcin; Wesseling, Evelyn; Balasubramaniyan, Veerakumar; Kuijer, Roelof; Vissink, Arjan; Copray, Sjef; Raghoebar, Gerry

    New developments in stem cell biology offer alternatives for the reconstruction of critical-sized bone defects. One of these developments is the use of induced pluripotent stem (iPS) cells. These stem cells are similar to embryonic stem (ES) cells, but can be generated from adult somatic cells and

  8. The number of stem cells in the subependymal zone of the adult rodent brain is correlated with the number of ependymal cells and not with the volume of the niche.

    Science.gov (United States)

    Kazanis, Ilias; Ffrench-Constant, Charles

    2012-05-01

    The mammalian subependymal zone (SEZ; often called subventricular) situated at the lateral walls of the lateral ventricles of the brain contains a pool of relatively quiescent adult neural stem cells whose neurogenic activity persists throughout life. These stem cells are positioned in close proximity both to the ependymal cells that provide the cerebrospinal fluid interface and to the blood vessel endothelial cells, but the relative contribution of these 2 cell types to stem cell regulation remains undetermined. Here, we address this question by analyzing a naturally occurring example of volumetric scaling of the SEZ in a comparison of the mouse SEZ with the larger rat SEZ. Our analysis reveals that the number of stem cells in the SEZ niche is correlated with the number of ependymal cells rather than with the volume, thereby indicating the importance of ependymal-derived factors in the formation and function of the SEZ. The elucidation of the factors generated by ependymal cells that regulate stem cell numbers within the SEZ is, therefore, of importance for stem cell biology and regenerative neuroscience.

  9. Comparative transcriptomic analysis of endothelial progenitor cells derived from umbilical cord blood and adult peripheral blood: Implications for the generation of induced pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Xiugong Gao

    2017-12-01

    Full Text Available Induced pluripotent stem cells (iPSCs offer the potential to generate tissues with ethnic diversity enabling toxicity testing on selected populations. Recently, it has been reported that endothelial progenitor cells (EPCs derived from umbilical cord blood (CB or adult peripheral blood (PB afford a practical and efficient cellular substrate for iPSC generation. However, differences between EPCs from different blood sources have rarely been studied. In the current study, we derived EPCs from blood mononuclear cells (MNCs and reprogrammed EPCs into iPSCs. We also explored differences between CB-EPCs and PB-EPCs at the molecular and cellular levels through a combination of transcriptomic analysis and cell biology techniques. EPC colonies in CB-MNCs emerged 5–7 days earlier, were 3-fold higher in number, and consistently larger in size than in PB-MNCs. Similarly, iPSC colonies generated from CB-EPCs was 2.5-fold higher in number than from PB-EPCs, indicating CB-EPCs have a higher reprogramming efficiency than PB-EPCs. Transcriptomic analysis using microarrays found a total of 1133 genes differentially expressed in CB-EPCs compared with PB-EPCs, with 675 genes upregulated and 458 downregulated. Several canonical pathways were impacted, among which the human embryonic stem cell pluripotency pathway was of particular interest. The differences in the gene expression pattern between CB-EPCs and PB-EPCs provide a molecular basis for the discrepancies seen in their derivation and reprogramming efficiencies, and highlight the advantages of using CB as the cellular source for the generation of iPSCs and their derivative tissues for ethnic-related toxicological applications.

  10. Comparative transcriptomic analysis of endothelial progenitor cells derived from umbilical cord blood and adult peripheral blood: Implications for the generation of induced pluripotent stem cells.

    Science.gov (United States)

    Gao, Xiugong; Yourick, Jeffrey J; Sprando, Robert L

    2017-12-01

    Induced pluripotent stem cells (iPSCs) offer the potential to generate tissues with ethnic diversity enabling toxicity testing on selected populations. Recently, it has been reported that endothelial progenitor cells (EPCs) derived from umbilical cord blood (CB) or adult peripheral blood (PB) afford a practical and efficient cellular substrate for iPSC generation. However, differences between EPCs from different blood sources have rarely been studied. In the current study, we derived EPCs from blood mononuclear cells (MNCs) and reprogrammed EPCs into iPSCs. We also explored differences between CB-EPCs and PB-EPCs at the molecular and cellular levels through a combination of transcriptomic analysis and cell biology techniques. EPC colonies in CB-MNCs emerged 5-7days earlier, were 3-fold higher in number, and consistently larger in size than in PB-MNCs. Similarly, iPSC colonies generated from CB-EPCs was 2.5-fold higher in number than from PB-EPCs, indicating CB-EPCs have a higher reprogramming efficiency than PB-EPCs. Transcriptomic analysis using microarrays found a total of 1133 genes differentially expressed in CB-EPCs compared with PB-EPCs, with 675 genes upregulated and 458 downregulated. Several canonical pathways were impacted, among which the human embryonic stem cell pluripotency pathway was of particular interest. The differences in the gene expression pattern between CB-EPCs and PB-EPCs provide a molecular basis for the discrepancies seen in their derivation and reprogramming efficiencies, and highlight the advantages of using CB as the cellular source for the generation of iPSCs and their derivative tissues for ethnic-related toxicological applications. Published by Elsevier B.V.

  11. Defining Optimized Properties of Modified mRNA to Enhance Virus- and DNA- Independent Protein Expression in Adult Stem Cells and Fibroblasts

    Directory of Open Access Journals (Sweden)

    Frauke Hausburg

    2015-02-01

    Full Text Available Background: By far, most strategies for cell reprogramming and gene therapy are based on the introduction of DNA after viral delivery. To avoid the high risks accompanying these goals, non-viral and DNA-free delivery methods for various cell types are required. Methods: Relying on an initially established PCR-based protocol for convenient template DNA production, we synthesized five differently modified EGFP mRNA (mmRNA species, incorporating various degrees of 5-methylcytidine-5'-triphosphate (5mC and pseudouridine-5'-triphosphate (Ψ. We then investigated their effect on i protein expression efficiencies and ii cell viability for human mesenchymal stem cells (hMSCs and fibroblasts from different origins. Results: Our protocol allows highly efficient mmRNA production in vitro, enabling rapid and stable protein expression after cell transfection. However, our results also demonstrate that the terminally optimal modification needs to be defined in pilot experiments for each particular cell type. Transferring our approach to the conversion of fibroblasts into skeletal myoblasts using mmRNA encoding MyoD, we confirm the huge potential of mmRNA based protein expression for virus- and DNA-free reprogramming strategies. Conclusion: The achieved high protein expression levels combined with good cell viability not only in fibroblasts but also in hMSCs provides a promising option for mmRNA based modification of various cell types including slowly proliferating adult stem cells. Therefore, we are confident that our findings will substantially contribute to the improvement of efficient cell reprogramming and gene therapy approaches.

  12. Bioengineering of cultured epidermis from adult epidermal stem cells using Mebio gel sutable as autologous graft material

    Directory of Open Access Journals (Sweden)

    Lakshmana K Yerneni

    2007-01-01

    Full Text Available Closure of burn wound is the primary requirement in order to reduce morbidity and mortality that are otherwise very high due to non-availability of permanent wound covering materials. Sheets of cultured epidermis grown from autologous epidermal keratinocyte stem cells are accepted world over as one of the best wound covering materials. In a largely populated country like ours where burn casualties occur more frequently due to inadequate safety practices, there is a need for indigenous research inputs to develop such methodologies. The technique to culturing epidermal sheets in vitro involves the basic Reheinwald-Green method with our own beneficial inputs. The technique employs attenuated 3T3 cells as feeders for propagating keratinocyte stem cells that are isolated from the epidermis of an initial skin biopsy of about 5 cm2 from the patient. The cultures are then maintained in Dulbecco's modified Eagle's medium strengthened with Ham's F12 formula, bovine fetal serum and various specific growth-promoting agents and factors in culture flasks under standard culture conditions. The primary cultures thus established would be serially passaged to achieve the required expansion. Our major inputs are into the establishment of (1 an efficient differential trypsinization protocol to isolate large number epidermal keratinocytes from the skin biopsy, (2 a highly specific, unique and foolproof attenuation protocol for 3T3 cells and (3 a specialized and significant decontamination protocol. The fully formed epidermal sheet as verified by immuno-histochemical and light & electron microscopic studies, is lifted on to paraffin gauze by incubating in a neutral protease. The graft is then ready to be transported to the operating theatre for autologous application. We have a capability of growing cultured epidermal sheets sufficient enough to cover 40 per cent burn wound in 28 days. The preliminary small area clinical applications undertaken so far revealed

  13. The Developmental Stage of Adult Human Stem Cell-Derived Retinal Pigment Epithelium Cells Influences Transplant Efficacy for Vision Rescue

    Directory of Open Access Journals (Sweden)

    Richard J. Davis

    2017-07-01

    Full Text Available Age-related macular degeneration (AMD is a common cause of central visual loss in the elderly. Retinal pigment epithelial (RPE cell loss occurs early in the course of AMD and RPE cell transplantation holds promise to slow disease progression. We report that subretinal transplantation of RPE stem cell (RPESC-derived RPE cells (RPESC-RPE preserved vision in a rat model of RPE cell dysfunction. Importantly, the stage of differentiation that RPESC-RPE acquired prior to transplantation influenced the efficacy of vision rescue. Whereas cells at all stages of differentiation tested rescued photoreceptor layer morphology, an intermediate stage of RPESC-RPE differentiation obtained after 4 weeks of culture was more consistent at vision rescue than progeny that were differentiated for 2 weeks or 8 weeks of culture. Our results indicate that the developmental stage of RPESC-RPE significantly influences the efficacy of RPE cell replacement, which affects the therapeutic application of these cells for AMD.

  14. The significance of the host inflammatory response on the therapeutic efficacy of cell therapies utilising human adult stem cells

    International Nuclear Information System (INIS)

    Navarro, Melba; Pu, Fanrong; Hunt, John A.

    2012-01-01

    Controlling the fate of implanted hMSCs is one of the major drawbacks to be overcome to realize tissue engineering strategies. In particular, the effect of the inflammatory environment on hMSCs behaviour is poorly understood. Studying and mimicking the inflammatory process in vitro is a very complex and challenging task that involves multiple variables. This research addressed the questions using in vitro co-cultures of primary derived hMSCs together with human peripheral blood mononucleated cells (PBMCs); the latter are key agents in the inflammatory process. This work explored the in vitro phenotypic changes of hMSCs in co-culture direct contact with monocytes and lymphocytes isolated from blood using both basal and osteogenic medium. Our findings indicated that hMSCs maintained their undifferentiated phenotype and pluripotency despite the contact with PBMCs. Moreover, hMSCs demonstrated increased proliferation and were able to differentiate specifically down the osteogenic lineage pathway. Providing significant crucial evidence to support the hypothesis that inflammation and host defence mechanisms could be utilised rather than avoided and combated to provide for the successful therapeutic application of stem cell therapies.

  15. Allogeneic hematopoietic stem cell transplant in adult patients with myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN) overlap syndromes.

    Science.gov (United States)

    Sharma, Prashant; Shinde, Shivani S; Damlaj, Moussab; Hefazi Rorghabeh, Mehrdad; Hashmi, Shahrukh K; Litzow, Mark R; Hogan, William J; Gangat, Naseema; Elliott, Michelle A; Al-Kali, Aref; Tefferi, Ayalew; Patnaik, Mrinal M

    2017-04-01

    MDS/MPN (myelodysplastic syndrome/myeloproliferative neoplasm) overlap syndromes are myeloid malignancies for which allogeneic hematopoietic stem cell transplant (allo-HSCT) is potentially curative. We describe transplant outcomes of 43 patients - 35 with chronic myelomonocytic leukemia, CMML (of which 17 had blast transformation, BT) and eight with MDS/MPN-unclassifiable (MDS/MPN,U). At median follow-up of 21 months, overall survival (OS), cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) were 55%, 29%, and 25% respectively in CMML without BT and 47%, 40%, and 34% respectively in CMML with BT. Higher HSCT-comorbidity index (HSCT-CI >3 versus ≤3; p = 0.015) and splenomegaly (p = 0.006) predicted worse OS in CMML without BT. In CMML with BT, engraftment failure (p = 0.006) and higher HSCT-CI (p = 0.03) were associated with inferior OS, while HSCT within 1-year of diagnosis was associated with improved OS (p = 0.045). In MDS/MPN,U, at median follow-up of 15 months, OS, CIR, and NRM were 62%, 30%, and 14%, respectively.

  16. Seipin knockout in mice impairs stem cell proliferation and progenitor cell differentiation in the adult hippocampal dentate gyrus via reduced levels of PPARγ

    Directory of Open Access Journals (Sweden)

    Guoxi Li

    2015-12-01

    Full Text Available The seipin gene (BSCL2 was originally identified in humans as a loss-of-function gene associated with congenital generalized lipodystrophy type 2 (CGL2. Neuronal seipin-knockout (seipin-nKO mice display a depression-like phenotype with a reduced level of hippocampal peroxisome proliferator-activated receptor gamma (PPARγ. The present study investigated the influence of seipin deficiency on adult neurogenesis in the hippocampal dentate gyrus (DG and the underlying mechanisms of the effects. We show that the proliferative capability of stem cells in seipin-nKO mice was substantially reduced compared to in wild-type (WT mice, and that this could be rescued by the PPARγ agonist rosiglitazone (rosi. In seipin-nKO mice, neuronal differentiation of progenitor cells was inhibited, with the enhancement of astrogliogenesis; both of these effects were recovered by rosi treatment during early stages of progenitor cell differentiation. In addition, rosi treatment could correct the decline in hippocampal ERK2 phosphorylation and cyclin A mRNA level in seipin-nKO mice. The MEK inhibitor U0126 abolished the rosi-rescued cell proliferation and cyclin A expression in seipin-nKO mice. In seipin-nKO mice, the hippocampal Wnt3 protein level was less than that in WT mice, and there was a reduction of neurogenin 1 (Neurog1 and neurogenic differentiation 1 (NeuroD1 mRNA, levels of which were corrected by rosi treatment. STAT3 phosphorylation (Tyr705 was enhanced in seipin-nKO mice, and was further elevated by rosi treatment. Finally, rosi treatment for 10 days could alleviate the depression-like phenotype in seipin-nKO mice, and this alleviation was blocked by the MEK inhibitor U0126. The results indicate that, by reducing PPARγ, seipin deficiency impairs proliferation and differentiation of neural stem and progenitor cells, respectively, in the adult DG, which might be responsible for the production of the depression-like phenotype in seipin-nKO mice.

  17. Endogenous stem cell proliferation induced by intravenous hedgehog agonist administration after contusion in the adult rat spinal cord.

    Science.gov (United States)

    Bambakidis, Nicholas C; Horn, Eric M; Nakaji, Peter; Theodore, Nicholas; Bless, Elizabeth; Dellovade, Tammy; Ma, Chiyuan; Wang, Xukui; Preul, Mark C; Coons, Stephen W; Spetzler, Robert F; Sonntag, Volker K H

    2009-02-01

    Sonic hedgehog (Shh) is a glycoprotein molecule that upregulates the transcription factor Gli1. The Shh protein plays a critical role in the proliferation of endogenous neural precursor cells when directly injected into the spinal cord after a spinal cord injury in adult rodents. Small-molecule agonists of the hedgehog (Hh) pathway were used in an attempt to reproduce these findings through intravenous administration. The expression of Gli1 was measured in rat spinal cord after the intravenous administration of an Hh agonist. Ten adult rats received a moderate contusion and were treated with either an Hh agonist (10 mg/kg, intravenously) or vehicle (5 rodents per group) 1 hour and 4 days after injury. The rats were killed 5 days postinjury. Tissue samples were immediately placed in fixative. Samples were immunohistochemically stained for neural precursor cells, and these cells were counted. Systemic dosing with an Hh agonist significantly upregulated Gli1 expression in the spinal cord (p < 0.005). After spinal contusion, animals treated with the Hh agonist had significantly more nestin-positive neural precursor cells around the rim of the lesion cavity than in vehicle-treated controls (means +/- SDs, 46.9 +/- 12.9 vs 20.9 +/- 8.3 cells/hpf, respectively, p < 0.005). There was no significant difference in the area of white matter injury between the groups. An intravenous Hh agonist at doses that upregulate spinal cord Gli1 transcription also increases the population of neural precursor cells after spinal cord injury in adult rats. These data support previous findings based on injections of Shh protein directly into the spinal cord.

  18. Transplantation of adult monkey neural stem cells into a contusion spinal cord injury model in rhesus macaque monkeys

    DEFF Research Database (Denmark)

    Nemati, Shiva Nemati; Jabbari, Reza; Hajinasrollah, Mostafa

    2014-01-01

    , therefore, to explore the efficacy of adult monkey NSC (mNSC) in a primate SCI model. MATERIALS AND METHODS: In this experimental study, isolated mNSCs were analyzed by flow cytometry, immunocytochemistry, and RT-PCR. Next, BrdU-labeled cells were transplanted into a SCI model. The SCI animal model...... on Tarlov's scale and our established behavioral tests for monkeys. CONCLUSION: Our findings have indicated that mNSCs can facilitate recovery in contusion SCI models in rhesus macaque monkeys. Additional studies are necessary to determine the im- provement mechanisms after cell transplantation....

  19. Colorectal cancer stem cells.

    Science.gov (United States)

    Salama, Paul; Platell, Cameron

    2009-10-01

    Somatic stem cells reside at the base of the crypts throughout the colonic mucosa. These cells are essential for the normal regeneration of the colonic epithelium. The stem cells reside within a special 'niche' comprised of intestinal sub-epithelial myofibroblasts that tightly control their function. It has been postulated that mutations within these adult colonic stem cells may induce neoplastic changes. Such cells can then dissociate from the epithelium and travel into the mesenchyme and thus form invasive cancers. This theory is based on the observation that within a colon cancer, less than 1% of the neoplastic cells have the ability to regenerate the tumour. It is this group of cells that exhibits characteristics of colonic stem cells. Although anti-neoplastic agents can induce remissions by inhibiting cell division, the stem cells appear to be remarkably resistant to both standard chemotherapy and radiotherapy. These stem cells may therefore persist after treatment and form the nucleus for cancer recurrence. Hence, future treatment modalities should focus specifically on controlling the cancer stem cells. In this review, we discuss the biology of normal and malignant colonic stem cells.

  20. Reduced circulating stem cells associate with excess fasting and post-load NEFA exposure in healthy adults with normal glucose tolerance.

    Science.gov (United States)

    Fadini, Gian Paolo; Tura, Andrea; Pacini, Giovanni; Avogaro, Angelo; Vigili de Kreutzenberg, Saula

    2017-06-01

    Reduced levels of circulating stem cells (CSCs) predict cardiovascular events and death, but the factors underlying variability of CSCs in healthy adults are mostly unknown. Previous studies detected associations of CSCs with glucose tolerance or insulin resistance, while the role of fatty acids has been overlooked. We herein aimed to describe in better detail the metabolic abnormalities associated with a reduced CSC level. This was a cross-sectional study on 94 healthy male and female individuals with normal glucose tolerance, aged 18-65 years. All participants underwent an oral glucose tolerance test (OGTT) with blood samples collected at 0, 10, 20, 30, 60, 90 and 120 min. Mathematical models were applied to plasma glucose, insulin, C-peptide and non-esterified fatty acids (NEFA) concentrations. CSCs were defined as CD34 + or CD133 + . Participants (mean ± SEM age 43.8 ± 0.7; 41% males) were divided according to CSC levels below (low) or above (high) the median value and metabolic parameters were compared. There was no significant baseline difference between groups except for higher concentrations of fasting NEFA in subjects with low CSCs. Upon OGTT, individuals with low CSCs had higher area under curve (AUC) of NEFA (p glucose, insulin and C-peptide. Several insulin sensitivity and beta cell function indexes were not significantly different, except for a decrease in the disposition index (DI) in subjects with low CSCs. CSCs were associated with excess NEFA levels independently from age and DI. We show for the first time that, in healthy adults with normal glucose tolerance, low CSCs are strongly associated with excess NEFA exposure. The pathophysiological consequence of this association needs to be interpreted in view of the prognostic role of CSCs. Future studies should explore whether excess NEFA and low CSCs and are causally interconnected. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Chromatin remodeling agent trichostatin A: a key-factor in the hepatic differentiation of human mesenchymal stem cells derived of adult bone marrow

    Directory of Open Access Journals (Sweden)

    Vinken Mathieu

    2007-04-01

    Full Text Available Abstract Background The capability of human mesenchymal stem cells (hMSC derived of adult bone marrow to undergo in vitro hepatic differentiation was investigated. Results Exposure of hMSC to a cocktail of hepatogenic factors [(fibroblast growth factor-4 (FGF-4, hepatocyte growth factor (HGF, insulin-transferrin-sodium-selenite (ITS and dexamethasone] failed to induce hepatic differentiation. Sequential exposure to these factors (FGF-4, followed by HGF, followed by HGF+ITS+dexamethasone, however, resembling the order of secretion during liver embryogenesis, induced both glycogen-storage and cytokeratin (CK18 expression. Additional exposure of the cells to trichostatin A (TSA considerably improved endodermal differentiation, as evidenced by acquisition of an epithelial morphology, chronological expression of hepatic proteins, including hepatocyte-nuclear factor (HNF-3β, alpha-fetoprotein (AFP, CK18, albumin (ALB, HNF1α, multidrug resistance-associated protein (MRP2 and CCAAT-enhancer binding protein (C/EBPα, and functional maturation, i.e. upregulated ALB secretion, urea production and inducible cytochrome P450 (CYP-dependent activity. Conclusion hMSC are able to undergo mesenchymal-to-epithelial transition. TSA is hereby essential to promote differentiation of hMSC towards functional hepatocyte-like cells.

  2. Biodistribution of adult derived human liver stem cells following intraportal infusion in a 17-year-old patient with glycogenosis type 1A

    International Nuclear Information System (INIS)

    Defresne, Florence; Tondreau, Tatiana; Stéphenne, Xavier; Smets, Françoise; Bourgois, Annick; Najimi, Mustapha; Jamar, François; Sokal, Etienne M.

    2014-01-01

    Introduction: Current treatment of inherited liver inborn errors of metabolism in children consists in appropriate diet and drugs and, for unstable patients, final orthotopic liver transplantation. Unfortunately, liver transplantation remains not easily available because of organ shortage and imposes inherent risks and lifelong immunosuppressive therapy. Therefore alternative treatments are required. Hepatocytes transplantation and its limitations led to consider innovative alternative such as transplantation of adult derived human liver stem cells (ADLHSC). These cells present high proliferative capacity, good resistance to cryopreservation and ability to differentiate into hepatocyte-like cells displaying mature hepatocyte functions. Aim: Biodistribution of ADHLSC had never been assessed after infusion through the portal vein in patients. This information is required to determine the safety of the method. Methods: ADHLSC were efficiently labelled with 111-Indium DTPA radiotracer and SPECT imaging was used for the acquisition of whole body imaging to document short term biodistribution of ADHLSC. Results: Following infusion through the portal vein, ADHLSC diffused homogenously throughout the liver and remained strictly within the targeted organ. Images were acquired until 5 days after infusion. At that time, no signal was observed in any other organs except the liver. Urinary excretion of 111-Indium DTPA was also monitored. Conclusion: For the first time, we documented the short term biodistribution of ADHLSC within the liver after infusion through the portal vein

  3. Comparisons of phenotype and immunomodulatory capacity among rhesus bone-marrow-derived mesenchymal stem/stromal cells, multipotent adult progenitor cells, and dermal fibroblasts

    Science.gov (United States)

    Wang, Qi; Clarkson, Christina; Graham, Melanie; Donahue, Robert; Hering, Bernhard J.; Verfaillie, Catherine M.; Bansal-Pakala, Pratima; O'Brien, Timothy D.

    2015-01-01

    Background Potent immunomodulatory effects have been reported for mesenchymal stem/stromal cells (MSCs), multipotent adult progenitor cells (MAPCs), and fibroblasts. However, side-by-side comparisons of these cells specifically regarding immunophenotype, gene expression, and suppression of proliferation of CD4+ and CD8+ lymphocyte populations have not been reported. Methods We developed MAPC and MSC lines from rhesus macaque bone marrow and fibroblast cell lines from rhesus dermis and assessed phenotypes based upon differentiation potential, flow cytometric analysis of immunophenotype, and quantitative RT-PCR analysis of gene expression. Using allogeneic lymphocyte proliferation assays, we compared the in vitro immunomodulatory potency of each cell type. Results and Conclusions Extensive phenotypic similarities exist among each cell type, although immunosuppressive potencies are distinct. MAPCs are most potent, and fibroblasts are the least potent cell type. All three cell types demonstrated immunomodulatory capacity such that each may have potential therapeutic applications such as in organ transplantation, where reduced local immune response is desirable. PMID:24825538

  4. Bilateral Transplantation of Allogenic Adult Human Bone Marrow-Derived Mesenchymal Stem Cells into the Subventricular Zone of Parkinson’s Disease: A Pilot Clinical Study

    Directory of Open Access Journals (Sweden)

    N. K. Venkataramana

    2012-01-01

    Full Text Available The progress of PD and its related disorders cannot be prevented with the medications available. In this study, we recruited 8 PD and 4 PD plus patients between 5 to 15 years after diagnosis. All patients received BM-MSCs bilaterally into the SVZ and were followed up for 12 months. PD patients after therapy reported a mean improvement of 17.92% during “on” and 31.21% during “off” period on the UPDRS scoring system. None of the patients increased their medication during the follow-up period. Subjectively, the patients reported clarity in speech, reduction in tremors, rigidity, and freezing attacks. The results correlated with the duration of the disease. Those patients transplanted in the early stages of the disease (less than 5 years showed more improvement and no further disease progression than the later stages (11–15 years. However, the PD plus patients did not show any change in their clinical status after stem cell transplantation. This study demonstrates the safety of adult allogenic human BM-MSCs transplanted into the SVZ of the brain and its efficacy in early-stage PD patients.

  5. Assessment of Effects of Si-Ca-P Biphasic Ceramic on the Osteogenic Differentiation of a Population of Multipotent Adult Human Stem Cells

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    Patricia Ros-Tárraga

    2016-11-01

    Full Text Available A new type of bioceramic with osteogenic properties, suitable for hard tissue regeneration, was synthesised. The ceramic was designed and obtained in the Nurse’s A-phase-silicocarnotite subsystem. The selected composition was that corresponding to the eutectoid 28.39 wt % Nurse’s A-phase-71.61 wt % silicocarnotite invariant point. We report the effect of Nurse’s A-phase-silicocarnotite ceramic on the capacity of multipotent adult human mesenchymal stem cells (ahMSCs cultured under experimental conditions, known to adhere, proliferate and differentiate into osteoblast lineage cells. The results at long-term culture (28 days on the material confirmed that the undifferentiated ahMSCs cultured and in contact with the material surface adhered, spread, proliferated, and produced a mineralised extracellular matrix on the studied ceramic, and finally acquired an osteoblastic phenotype. These findings indicate that it underwent an osteoblast differentiation process. All these findings were more significant than when cells were grown on plastic, in the presence and absence of this osteogenic supplement, and were more evident when this supplement was present in the growth medium (GM. The ceramic evaluated herein was bioactive, cytocompatible and capable of promoting the proliferation and differentiation of undifferentiated ahMSCs into osteoblasts, which may be important for bone integration into the clinical setting.

  6. In vitro evidence for impaired neuroprotective capacities of adult mesenchymal stem cells derived from a rat model of familial amyotrophic lateral sclerosis (hSOD1(G93A)).

    Science.gov (United States)

    Boucherie, Cédric; Caumont, Anne-Sophie; Maloteaux, Jean-Marie; Hermans, Emmanuel

    2008-08-01

    Protection of neurons by stem cells is an attractive challenge in the development of efficient therapies of neurodegenerative diseases. When giving preference to autologous grafts, the bone marrow constitutes a valuable source of adult stem cells. Therefore, we herein studied the acquisition of neuroprotective functions by cultured mesenchymal stem cells (MSCs) exposed to growth factors known to promote the differentiation of neural stem cells into astrocytes. In these conditions, MSCs showed increased transcription and expression of the high-affinity glutamate transporter GLT-1 and functional studies revealed increased aspartate uptake activity. In addition, differentiation was shown to endow the cells with the capacity to respond to riluzole which triggers a robust up-regulation of the GDNF production. In parallel, MSCs derived from the bone marrow of a transgenic rat model of familial ALS (hSOD1(G93A)) were also characterised. Unexpectedly, cells from this rat strain submitted to the differentiation protocol showed modest capacity to take up aspartate and did not respond to the riluzole treatments. These data highlight the neuroprotective potential attributable to MSCs, supporting their use as valuable tools for the treatment of neurodegenerative disorders. However, the cells from the transgenic animal model of ALS appeared deficient in their capacity to gain the neuroprotective properties, raising questions regarding the suitability of autologous stem cell grafts in future therapies against familial forms of this disease.

  7. Stem cells in dentistry: A study regarding awareness of stem cells among dental professionals

    OpenAIRE

    Parita K Chitroda; Girish Katti; Nikhat M Attar; Syed Shahbaz; G Sreenivasarao; Ambika Patil

    2017-01-01

    Background: Dental stem cell, a type of adult stem cell, exhibits multipotent differentiation capacity and is drawing worldwide attention because of its numerous applications. The advances in applications of dental stem cells seem to be unsurpassed in the near future, for which specialized skills and knowledge in this arena are of prime significance. Hence, there is a need to acquire more knowledge about dental stem cells to obtain maximum benefits from it in the coming years. Dental stem cel...

  8. In-vivo generation of bone via endochondral ossification by in-vitro chondrogenic priming of adult human and rat mesenchymal stem cells

    LENUS (Irish Health Repository)

    Farrell, Eric

    2011-01-31

    Abstract Background Bone grafts are required to repair large bone defects after tumour resection or large trauma. The availability of patients\\' own bone tissue that can be used for these procedures is limited. Thus far bone tissue engineering has not lead to an implant which could be used as alternative in bone replacement surgery. This is mainly due to problems of vascularisation of the implanted tissues leading to core necrosis and implant failure. Recently it was discovered that embryonic stem cells can form bone via the endochondral pathway, thereby turning in-vitro created cartilage into bone in-vivo. In this study we investigated the potential of human adult mesenchymal stem cells to form bone via the endochondral pathway. Methods MSCs were cultured for 28 days in chondrogenic, osteogenic or control medium prior to implantation. To further optimise this process we induced mineralisation in the chondrogenic constructs before implantation by changing to osteogenic medium during the last 7 days of culture. Results After 8 weeks of subcutaneous implantation in mice, bone and bone marrow formation was observed in 8 of 9 constructs cultured in chondrogenic medium. No bone was observed in any samples cultured in osteogenic medium. Switch to osteogenic medium for 7 days prevented formation of bone in-vivo. Addition of β-glycerophosphate to chondrogenic medium during the last 7 days in culture induced mineralisation of the matrix and still enabled formation of bone and marrow in both human and rat MSC cultures. To determine whether bone was formed by the host or by the implanted tissue we used an immunocompetent transgenic rat model. Thereby we found that osteoblasts in the bone were almost entirely of host origin but the osteocytes are of both host and donor origin. Conclusions The preliminary data presented in this manuscript demonstrates that chondrogenic priming of MSCs leads to bone formation in vivo using both human and rat cells. Furthermore, addition of

  9. Differences in Contractile Function of Myofibrils within Human Embryonic Stem Cell-Derived Cardiomyocytes vs. Adult Ventricular Myofibrils Are Related to Distinct Sarcomeric Protein Isoforms

    Directory of Open Access Journals (Sweden)

    Bogdan Iorga

    2018-01-01

    Full Text Available Characterizing the contractile function of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs is key for advancing their utility for cellular disease models, promoting cell based heart repair, or developing novel pharmacological interventions targeting cardiac diseases. The aim of the present study was to understand whether steady-state and kinetic force parameters of β-myosin heavy chain (βMyHC isoform-expressing myofibrils within human embryonic stem cell-derived cardiomyocytes (hESC-CMs differentiated in vitro resemble those of human ventricular myofibrils (hvMFs isolated from adult donor hearts. Contractile parameters were determined using the same micromechanical method and experimental conditions for both types of myofibrils. We identified isoforms and phosphorylation of main sarcomeric proteins involved in the modulation of force generation of both, chemically demembranated hESC-CMs (d-hESC-CMs and hvMFs. Our results indicate that at saturating Ca2+ concentration, both human-derived contractile systems developed forces with similar rate constants (0.66 and 0.68 s−1, reaching maximum isometric force that was significantly smaller for d-hESC-CMs (42 kPa than for hvMFs (94 kPa. At submaximal Ca2+-activation, where intact cardiomyocytes normally operate, contractile parameters of d-hESC-CMs and hvMFs exhibited differences. Ca2+ sensitivity of force was higher for d-hESC-CMs (pCa50 = 6.04 than for hvMFs (pCa50 = 5.80. At half-maximum activation, the rate constant for force redevelopment was significantly faster for d-hESC-CMs (0.51 s−1 than for hvMFs (0.28 s−1. During myofibril relaxation, kinetics of the slow force decay phase were significantly faster for d-hESC-CMs (0.26 s−1 than for hvMFs (0.21 s−1, while kinetics of the fast force decay were similar and ~20x faster. Protein analysis revealed that hESC-CMs had essentially no cardiac troponin-I, and partially non-ventricular isoforms of some other sarcomeric proteins

  10. Types of Stem Cells

    Science.gov (United States)

    ... Stem Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... Learn About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

  11. Aging and insulin signaling differentially control normal and tumorous germline stem cells.

    Science.gov (United States)

    Kao, Shih-Han; Tseng, Chen-Yuan; Wan, Chih-Ling; Su, Yu-Han; Hsieh, Chang-Che; Pi, Haiwei; Hsu, Hwei-Jan

    2015-02-01

    Aging influences stem cells, but the processes involved remain unclear. Insulin signaling, which controls cellular nutrient sensing and organismal aging, regulates the G2 phase of Drosophila female germ line stem cell (GSC) division cycle in response to diet; furthermore, this signaling pathway is attenuated with age. The role of insulin signaling in GSCs as organisms age, however, is also unclear. Here, we report that aging results in the accumulation of tumorous GSCs, accompanied by a decline in GSC number and proliferation rate. Intriguingly, GSC loss with age is hastened by either accelerating (through eliminating expression of Myt1, a cell cycle inhibitory regulator) or delaying (through mutation of insulin receptor (dinR) GSC division, implying that disrupted cell cycle progression and insulin signaling contribute to age-dependent GSC loss. As flies age, DNA damage accumulates in GSCs, and the S phase of the GSC cell cycle is prolonged. In addition, GSC tumors (which escape the normal stem cell regulatory microenvironment, known as the niche) still respond to aging in a similar manner to normal GSCs, suggesting that niche signals are not required for GSCs to sense or respond to aging. Finally, we show that GSCs from mated and unmated females behave similarly, indicating that female GSC-male communication does not affect GSCs with age. Our results indicate the differential effects of aging and diet mediated by insulin signaling on the stem cell division cycle, highlight the complexity of the regulation of stem cell aging, and describe a link between ovarian cancer and aging. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  12. Allogeneic stem cell transplantation for adult patients with acute lymphoblastic leukemia who had central nervous system involvement: a study from the Adult ALL Working Group of the Japan Society for Hematopoietic Cell Transplantation.

    Science.gov (United States)

    Shigematsu, Akio; Kako, Shinichi; Mitsuhashi, Kenjiro; Iwato, Koji; Uchida, Naoyuki; Kanda, Yoshinobu; Fukuda, Takahiro; Sawa, Masashi; Senoo, Yasushi; Ogawa, Hiroyasu; Miyamura, Koichi; Takada, Satoru; Nagamura-Inoue, Tokiko; Morishima, Yasuo; Ichinohe, Tatsuo; Atsuta, Yoshiko; Mizuta, Shuichi; Tanaka, Junji

    2017-06-01

    The prognosis for adult acute lymphoblastic leukemia (ALL) patients with central nervous system (CNS) involvement (CNS+) who received allogeneic hematopoietic stem cell transplantation (allo-SCT) remains unclear. We retrospectively compared the outcomes of allo-SCT for patients with CNS involvement and for patients without CNS involvement (CNS-) using a database in Japan. The eligibility criteria for this study were as follows: diagnosis of ALL, aged more than 16 years, allo-SCT between 2005 and 2012, and first SCT. Data for 2582 patients including 136 CNS+ patients and 2446 CNS- patients were used for analyses. As compared with CNS- patients, CNS+ patients were younger, had worse disease status at SCT and had poorer performance status (PS) at SCT (P < 0.01). Incidence of relapse was higher in CNS+ patients (P = 0.02), and incidence of CNS relapse was also higher (P < 0.01). The probability of 3-year overall survival (OS) was better in CNS- patients (P < 0.01) by univariate analysis. However, in patients who received SCT in CR, there was no difference in the probability of OS between CNS+ and CNS- patients (P = 0.38) and CNS involvement did not have an unfavorable effect on OS by multivariate analysis. CNS+ patients who achieved CR showed OS comparable to that of CNS- patients.

  13. Stem cell migration after irradiation

    International Nuclear Information System (INIS)

    Nothdurft, W.; Fliedner, T.M.

    1979-01-01

    The survival rate of irradiated rodents could be significantly improved by shielding only the small parts of hemopoietic tissues during the course of irradiation. The populations of circulating stem cells in adult organisms are considered to be of some importance for the homeostasis between the many sites of blood cell formation and for the necessary flexibility of hemopoietic response in the face of fluctuating demands. Pluripotent stem cells are migrating through peripheral blood as has been shown for several mammalian species. Under steady state conditions, the exchange of stem cells between the different sites of blood cell formation appears to be restricted. Their presence in blood and the fact that they are in balance with the extravascular stem cell pool may well be of significance for the surveilance of the integrity of local stem cell populations. Any decrease of stem cell population in blood below a critical size results in the rapid immigration of circulating stem cells in order to restore local stem cell pool size. Blood stem cells are involved in the regeneration after whole-body irradiation if the stem cell population in bone marrows is reduced to less than 10% of the normal state. In the animals subjected to partial-body irradiation, the circulating stem cells appear to be the only source for the repopulation of the heavily irradiated, aplastic sites of hemopoietic organs. (Yamashita, S.)

  14. Genome engineering via homologous recombination in mouse embryonic stem (ES cells: an amazingly versatile tool for the study of mammalian biology

    Directory of Open Access Journals (Sweden)

    BABINET CHARLES

    2001-01-01

    Full Text Available The ability to introduce genetic modifications in the germ line of complex organisms has been a long-standing goal of those who study developmental biology. In this regard, the mouse, a favorite model for the study of the mammals, is unique: indeed not only is it possible since the late seventies, to add genes to the mouse genome like in several other complex organisms but also to perform gene replacement and modification. This has been made possible via two technological breakthroughs: 1 the isolation and culture of embryonic stem cells (ES, which have the unique ability to colonize all the tissues of an host embryo including its germ line; 2 the development of methods allowing homologous recombination between an incoming DNA and its cognate chromosomal sequence (gene ''targeting''. As a result, it has become possible to create mice bearing null mutations in any cloned gene (knock-out mice. Such a possibility has revolutionized the genetic approach of almost all aspects of the biology of the mouse. In recent years, the scope of gene targeting has been widened even more, due to the refinement of the knock-out technology: other types of genetic modifications may now be created, including subtle mutations (point mutations, micro deletions or insertions, etc. and chromosomal rearrangements such as large deletions, duplications and translocations. Finally, methods have been devised which permit the creation of conditional mutations, allowing the study of gene function throughout the life of an animal, when gene inactivation entails embryonic lethality. In this paper, we present an overview of the methods and scenarios used for the programmed modification of mouse genome, and we underline their enormous interest for the study of mammalian biology.

  15. Successful Isolation of Viable Adipose-Derived Stem Cells from Human Adipose Tissue Subject to Long-Term Cryopreservation: Positive Implications for Adult Stem Cell-Based Therapeutics in Patients of Advanced Age

    Directory of Open Access Journals (Sweden)

    Sean M. Devitt

    2015-01-01

    Full Text Available We examined cell isolation, viability, and growth in adipose-derived stem cells harvested from whole adipose tissue subject to different cryopreservation lengths (2–1159 days from patients of varying ages (26–62 years. Subcutaneous abdominal adipose tissue was excised during abdominoplasties and was cryopreserved. The viability and number of adipose-derived stem cells isolated were measured after initial isolation and after 9, 18, and 28 days of growth. Data were analyzed with respect to cryopreservation duration and patient age. Significantly more viable cells were initially isolated from tissue cryopreserved 2 years, irrespective of patient age. However, this difference did not persist with continued growth and there were no significant differences in cell viability or growth at subsequent time points with respect to cryopreservation duration or patient age. Mesenchymal stem cell markers were maintained in all cohorts tested throughout the duration of the study. Consequently, longer cryopreservation negatively impacts initial live adipose-derived stem cell isolation; however, this effect is neutralized with continued cell growth. Patient age does not significantly impact stem cell isolation, viability, or growth. Cryopreservation of adipose tissue is an effective long-term banking method for isolation of adipose-derived stem cells in patients of varying ages.

  16. Chromosome copy number variation in telomerized human bone marrow stromal cells; insights for monitoring safe ex-vivo expansion of adult stem cells.

    Science.gov (United States)

    Burns, Jorge S; Harkness, Linda; Aldahmash, Abdullah; Gautier, Laurent; Kassem, Moustapha

    2017-12-01

    Adult human bone marrow stromal cells (hBMSC) cultured for cell therapy require evaluation of potency and stability for safe use. Chromosomal aberrations upsetting genomic integrity in such cells have been contrastingly described as "Limited" or "Significant". Previously reported stepwise acquisition of a spontaneous neoplastic phenotype during three-year continuous culture of telomerized cells (hBMSC-TERT20) didn't alter a diploid karyotype measured by spectral karyotype analysis (SKY). Such screening may not adequately monitor abnormal and potentially tumorigenic hBMSC in clinical scenarios. We here used array comparative genomic hybridization (aCGH) to more stringently compare non-tumorigenic parental hBMSC-TERT strains with their tumorigenic subcloned populations. Confirmation of a known chromosome 9p21 microdeletion at locus CDKN2A/B, showed it also impinged upon the adjacent MTAP gene. Compared to reference diploid human fibroblast genomic DNA, the non-tumorigenic hBMSC-TERT4 cells had a copy number variation (CNV) in at least 14 independent loci. The pre-tumorigenic hBMSC-TERT20 cell strain had further CNV including 1q44 gain enhancing SMYD3 expression and 11q13.1 loss downregulating MUS81 expression. Bioinformatic analysis of gene products reflecting 11p15.5 CNV gain in tumorigenic hBMSC-TERT20 cells highlighted networks implicated in tumorigenic progression involving cell cycle control and mis-match repair. We provide novel biomarkers for prospective risk assessment of expanded stem cell cultures. Copyright © 2017. Published by Elsevier B.V.

  17. In vitro evaluation of biocompatibility of uncoated thermally reduced graphene and carbon nanotube-loaded PVDF membranes with adult neural stem cell-derived neurons and glia

    Directory of Open Access Journals (Sweden)

    Çagla Defterali

    2016-12-01

    Full Text Available Graphene, graphene-based nanomaterials (GBNs and carbon nanotubes (CNTs are being investigated as potential substrates for the growth of neural cells. However, in most in vitro studies the cells were seeded on these materials coated with various proteins implying that the observed effects on the cells could not solely be attributed to the GBN and CNT properties. Here we studied the biocompatibility of uncoated thermally reduced graphene (TRG and poly-vinylidene fluoride (PVDF membranes loaded with multi walled CNTs (MWCNTs using neural stem cells (NSCs isolated from the adult mouse olfactory bulb (termed aOBSCs. When aOBSCs were induced to differentiate on coverslips treated with TRG or control materials (polyethyleneimine-PEI and polyornithine plus fibronectin-PLO/F in a serum-free medium, neurons, astrocytes, and oligodendrocytes were generated in all conditions, indicating that TRG permits the multi-lineage differentiation of aOBSCs. However, the total number of cells was reduced on both PEI and TRG. In a serum-containing medium, aOBSC-derived neurons and oligodendrocytes grown on TRG were more numerous than in controls; the neurons developed synaptic boutons and oligodendrocytes were more branched. In contrast, neurons growing on PVDF membranes had reduced neurite branching and on MWCNTs-loaded membranes, oligodendrocytes were lower in numbers than in controls. Overall, these findings indicate that uncoated TRG may be biocompatible with the generation, differentiation, and maturation of aOBSC-derived neurons and glial cells, implying a potential use for TRG to study functional neuronal networks.

  18. Lead induces similar gene expression changes in brains of gestationally exposed adult mice and in neurons differentiated from mouse embryonic stem cells.

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    Francisco Javier Sánchez-Martín

    Full Text Available Exposure to environmental toxicants during embryonic life causes changes in the expression of developmental genes that may last for a lifetime and adversely affect the exposed individual. Developmental exposure to lead (Pb, an ubiquitous environmental contaminant, causes deficits in cognitive functions and IQ, behavioral effects, and attention deficit hyperactivity disorder (ADHD. Long-term effects observed after early life exposure to Pb include reduction of gray matter, alteration of myelin structure, and increment of criminal behavior in adults. Despite growing research interest, the molecular mechanisms responsible for the effects of lead in the central nervous system are still largely unknown. To study the molecular changes due to Pb exposure during neurodevelopment, we exposed mice to Pb in utero and examined the expression of neural markers, neurotrophins, transcription factors and glutamate-related genes in hippocampus, cortex, and thalamus at postnatal day 60. We found that hippocampus was the area where gene expression changes due to Pb exposure were more pronounced. To recapitulate gestational Pb exposure in vitro, we differentiated mouse embryonic stem cells (ESC into neurons and treated ESC-derived neurons with Pb for the length of the differentiation process. These neurons expressed the characteristic neuronal markers Tubb3, Syp, Gap43, Hud, Ngn1, Vglut1 (a marker of glutamatergic neurons, and all the glutamate receptor subunits, but not the glial marker Gafp. Importantly, several of the changes observed in Pb-exposed mouse brains in vivo were also observed in Pb-treated ESC-derived neurons, including those affecting expression of Ngn1, Bdnf exon IV, Grin1, Grin2D, Grik5, Gria4, and Grm6. We conclude that our ESC-derived model of toxicant exposure during neural differentiation promises to be a useful model to analyze mechanisms of neurotoxicity induced by Pb and other environmental agents.

  19. Comparisons Between Allogeneic Peripheral Blood Stem Cell Transplantation and Allogeneic Bone Marrow Transplantation in Adult Hematologic Disease: A Single Center Experience

    Directory of Open Access Journals (Sweden)

    Yi-Chang Liu

    2003-11-01

    Full Text Available This retrospective study compared the outcomes in 32 adult patients with hematologic diseases (acute myeloid leukemia, acute lymphoblastic leukemia, chronic myeloid leukemia, myelodysplastic syndrome, severe aplastic anemia who received allogeneic bone marrow transplantation (BMT, n = 14; median age, 28 years or allogeneic peripheral blood stem cell transplantation (PBSCT, n = 18; median age, 29 years from human leukocyte antigen-identical sibling donors. Median follow-up was 58 months in BMT recipients and 18 months in PBSCT recipients. Neutrophil (median, Day 8 vs Day 13, p < 0.001 and platelet engraftment (median, Day 9 vs Day 17, p < 0.001 was faster in the PBSCT group than in the BMT group. Patients receiving PBSCT required less platelet transfusion than those receiving BMT (median, 54 units vs 144 units, p < 0.001, but there was no significant difference in red cell transfusion. At 100 days, there was no difference in the incidence of acute graft-versus-host disease (GVHD (42.9% vs 33.3%, p = 0.72 or grade II-IV acute GVHD (14.3% vs 5.6%, p = 0.57, and there was no difference in the cumulative incidence of chronic GVHD (20% vs 33.3%, p = 0.67. No chronic GVHD was noted in any relapsed patients (BMT, 5; PBSCT, 3, and no patients with chronic GVHD during follow-up had a relapse. Relapse was the most frequent cause of death in both groups (BMT, 5/9, 55.6%; PBSCT, 3/4, 75%; p = 0.25; all relapses occurred within 1 year after transplantation. Overall survival was significantly better in the PBSCT group (35.7% vs 77.8%, p = 0.029, but this difference was lost if only hematologic malignancies were analyzed (30.8% vs 63.6%, p = 0.20. Our results are similar to those reported previously, with faster neutrophil and platelet engraftment and less severe acute GVHD and extensive chronic GVHD with PBSCT. Allogeneic PBSCT is a feasible and beneficial alternative to allogeneic BMT in adult hematologic disease.

  20. The potential application of stem cell in dentistry

    Directory of Open Access Journals (Sweden)

    Ketut Suardita

    2006-12-01

    Full Text Available Stem cells are generally defined as cells that have the capacity to self-renewal and differentiate to specialize cell. There are two kinds of stem cell, embryonic stem cell and adult stem cells. Stem cell therapy has been used to treat diseases including Parkinson’s and Alzheimer’s diseases, spinal cord injury, stroke, burns, heart diseases, diabetes, osteoarthritis, and rheumatoid arthritis. Stem cells were found in dental pulp, periodontal ligament, and alveolar bone marrow. Because of their potential in medical therapy, stem cells were used to regenerate lost or damage teeth and periodontal structures. This article discusses the potential application of stem cells for dental field.

  1. Haematopoietic transplants combining a single unrelated cord blood unit and mobilized haematopoietic stem cells from an adult HLA-mismatched third party donor. Comparable results to transplants from HLA-identical related donors in adults with acute leukaemia and myelodysplastic syndromes.

    Science.gov (United States)

    Sebrango, Ana; Vicuña, Isabel; de Laiglesia, Almudena; Millán, Isabel; Bautista, Guiomar; Martín-Donaire, Trinidad; Regidor, Carmen; Cabrera, Rafael; Fernandez, Manuel N

    2010-06-01

    We describe results of the strategy, developed by our group, of co-infusion of mobilized haematopoietic stem cells as a support for single-unit unrelated cord blood transplant (dual CB/TPD-MHSC transplants) for treatment of haematological malignancies in adults, and a comparative analysis of results obtained using this strategy and transplants performed with mobilized haematopoietic stem cells from related HLA-identical donors (RTD) for treatment of adults with acute leukaemia and myelodysplastic syndromes. Our data show that the dual CB/TPD-MHSC transplant strategy results in periods of post-transplant neutropenia, final rates of full donor chimerism and transplant-related mortality rates comparable to those of the RTD. Final survival outcomes are comparable in adults transplanted because of acute leukaemia, with different incidences of the complications that most influence these: a higher incidence of infections related to late recovery of protective immunity dependent on T cell functions, and a lower incidence of serious acute graft-versus-host disease and relapses. Recent advances in cord blood transplant techniques allow allogeneic haematopoietic stem cell transplantation (HSCT) to be a viable option for almost every patient who may benefit from this therapeutic approach. Development of innovative strategies to improve the post-transplant recovery of T cells function is currently the main challenge to further improving the possibilities of unrelated cord blood transplantation. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Quality of Life and Psychopathology in Adults Who Underwent Hematopoietic Stem Cell Transplantation (HSCT in Childhood: A Qualitative and Quantitative Analysis

    Directory of Open Access Journals (Sweden)

    Francesco Sinatora

    2017-08-01

    Full Text Available Background: Patients who undergo pediatric Hematopoietic Stem Cell Transplantation (HSCT may experience long-term psychological sequelae and poor Quality of Life (QoL in adulthood. This study aimed to investigate subjective illness experience, QoL, and psychopathology in young adults who have survived pediatric HSCT.Method: The study involved patients treated with HSCT in the Hematology-Oncology Department between 1984 and 2007. Psychopathology and QoL were investigated using the SCL-90-R and SF-36. Socio-demographic and medical information was also collected. Finally, participants were asked to write a brief composition about their experiences of illness and care. Qualitative analysis of the texts was performed using T-LAB, an instrument for text analysis that allows the user to highlight the occurrences and co-occurrences of lemma. Quantitative analyses were performed using non-parametric tests (Spearman correlations, Kruskal-Wallis and Mann-Whitney tests.Results: Twenty-one patients (9 males participated in the study. No significant distress was found on the SCL-90 Global Severity Index, but it was found on specific scales. On the SF-36, lower scores were reported on scales referring to bodily pain, general health, and physical and social functioning. All the measures were significantly (p < 0.05 associated with specific socio-demographic and medical variables (gender, type of pathology, type of HSCT, time elapsed between communication of the need to transplant and effective transplantation, and days of hospitalization. With regard to the narrative analyses, males focused on expressions related to the body and medical therapies, while females focused on people they met during treatment, family members, and donors. Low general health and treatment with autologous HSCT were associated with memories about chemotherapy, radiotherapy, and the body parts involved, while high general health was associated with expressions focused on gratitude (V

  3. Different DNA damage response of cis and trans isomers of commonly used UV filter after the exposure on adult human liver stem cells and human lymphoblastoid cells.

    Science.gov (United States)

    Sharma, Anežka; Bányiová, Katarína; Babica, Pavel; El Yamani, Naouale; Collins, Andrew Richard; Čupr, Pavel

    2017-09-01

    2-ethylhexyl 4-methoxycinnamate (EHMC), used in many categories of personal care products (PCPs), is one of the most discussed ultraviolet filters because of its endocrine-disrupting effects. EHMC is unstable in sunlight and can be transformed from trans-EHMC to emergent cis-EHMC. Toxicological studies are focusing only on trans-EHMC; thus the toxicological data for cis-EHMC are missing. In this study, the in vitro genotoxic effects of trans- and cis-EHMC on adult human liver stem cells HL1-hT1 and human-derived lymphoblastoid cells TK-6 using a high-throughput comet assay were studied. TK-6 cells treated with cis-EHMC showed a high level of DNA damage when compared to untreated cells in concentrations 1.56 to 25μgmL -1 . trans-EHMC showed genotoxicity after exposure to the two highest concentrations 12.5 and 25μgmL -1 . The increase in DNA damage on HL1-hT1 cells induced by cis-EHMC and trans-EHMC was detected at the concentration 25μgmL -1 . The No observed adverse effect level (NOAEL, mg kg -1 bwday -1 ) was determined using a Quantitative in vitro to in vivo extrapolation (QIVIVE) approach: NOAEL trans-EHMC =3.07, NOAEL cis-EHMC =0.30 for TK-6 and NOAEL trans-EHMC =26.46, NOAEL cis-EHMC =20.36 for HL1-hT1. The hazard index (HI) was evaluated by comparing the reference dose (RfD, mgkg -1 bwday -1 ) obtained from our experimental data with the chronic daily intake (CDI) of the female population. Using comet assay experimental data with the more sensitive TK-6 cells, HI cis-EHMC was 7 times higher than HI trans-EHMC . In terms of CDI, relative contributions were; dermal exposure route>oral>inhalation. According to our results we recommend the RfD trans-EHMC =0.20 and RfD cis-EHMC =0.02 for trans-EHMC and cis-EHMC, respectively, to use for human health risk assessment. The significant difference in trans-EHMC and cis-EHMC response points to the need for toxicological reevaluation and application reassessment of both isomers in PCPs. Copyright © 2017 Elsevier B

  4. Establishment of new murine embryonic stem cell lines for the generation of mouse models of human genetic diseases

    Directory of Open Access Journals (Sweden)

    M.A. Sukoyan

    2002-05-01

    Full Text Available Embryonic stem cells are totipotent cells derived from the inner cell mass of blastocysts. Recently, the development of appropriate culture conditions for the differentiation of these cells into specific cell types has permitted their use as potential therapeutic agents for several diseases. In addition, manipulation of their genome in vitro allows the creation of animal models of human genetic diseases and for the study of gene function in vivo. We report the establishment of new lines of murine embryonic stem cells from preimplantation stage embryos of 129/Sv mice. Most of these cells had a normal karyotype and an XY sex chromosome composition. The pluripotent properties of the cell lines obtained were analyzed on the basis of their alkaline phosphatase activity and their capacity to form complex embryoid bodies with rhythmically contracting cardiomyocytes. Two lines, USP-1 and USP-3, with the best in vitro characteristics of pluripotency were used in chimera-generating experiments. The capacity to contribute to the germ line was demonstrated by the USP-1 cell line. This cell line is currently being used to generate mouse models of human diseases.

  5. Stem cells in dentistry--part I: stem cell sources.

    Science.gov (United States)

    Egusa, Hiroshi; Sonoyama, Wataru; Nishimura, Masahiro; Atsuta, Ikiru; Akiyama, Kentaro

    2012-07-01

    Stem cells can self-renew and produce different cell types, thus providing new strategies to regenerate missing tissues and treat diseases. In the field of dentistry, adult mesenchymal stem/stromal cells (MSCs) have been identified in several oral and maxillofacial tissues, which suggests that the oral tissues are a rich source of stem cells, and oral stem and mucosal cells are expected to provide an ideal source for genetically reprogrammed cells such as induced pluripotent stem (iPS) cells. Furthermore, oral tissues are expected to be not only a source but also a therapeutic target for stem cells, as stem cell and tissue engineering therapies in dentistry continue to attract increasing clinical interest. Part I of this review outlines various types of intra- and extra-oral tissue-derived stem cells with regard to clinical availability and applications in dentistry. Additionally, appropriate sources of stem cells for regenerative dentistry are discussed with regard to differentiation capacity, accessibility and possible immunomodulatory properties. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  6. Socializing with the neighbors: stem cells and their niche.

    Science.gov (United States)

    Fuchs, Elaine; Tumbar, Tudorita; Guasch, Geraldine

    2004-03-19

    The potential of stem cells in regenerative medicine relies upon removing them from their natural habitat, propagating them in culture, and placing them into a foreign tissue environment. To do so, it is essential to understand how stem cells interact with their microenvironment, the so-called stem cell niche, to establish and maintain their properties. In this review, we examine adult stem cell niches and their impact on stem cell biology.

  7. Design of a nanocomposite substrate inducing adult stem cell assembly and progression toward an Epiblast-like or Primitive Endoderm-like phenotype via mechanotransduction.

    Science.gov (United States)

    Morena, Francesco; Armentano, Ilaria; Montanucci, Pia; Argentati, Chiara; Fortunati, Elena; Montesano, Simona; Bicchi, Ilaria; Pescara, Teresa; Pennoni, Ilaria; Mattioli, Samantha; Torre, Luigi; Latterini, Loredana; Emiliani, Carla; Basta, Giuseppe; Calafiore, Riccardo; Kenny, Josè Maria; Martino, Sabata

    2017-11-01

    This work shows that the active interaction between human umbilical cord matrix stem cells and Poly (l-lactide)acid (PLLA) and PLLA/Multi Walled Carbon Nanotubes (MWCNTs) nanocomposite films results in the stem cell assembly as a spheroid conformation and affects the stem cell fate transition. We demonstrated that spheroids directly respond to a tunable surface and the bulk properties (electric, dielectric and thermal) of plain and nanocomposite PLLA films by triggering a mechanotransduction axis. This stepwise process starts from tethering of the cells' focal adhesion proteins to the surface, together with the adherens junctions between cells. Both complexes transmit traction forces to F-Actin stress fibres that link Filamin-A and Myosin-IIA proteins, generating a biological scaffold, with increased stiffening conformation from PLLA to PLLA/MWCNTs, and enable the nucleoskeleton proteins to boost chromatin reprogramming processes. Herein, the opposite expression of NANOG and GATA6 transcription factors, together with other lineage specification related proteins, steer spheroids toward an Epiblast-like or Primitive Endoderm-like lineage commitment, depending on the absence or presence of 1 wt% MWCNTs, respectively. This work represents a pioneering effort to create a stem cell/material interface that can model the stem cell fate transition under growth culture conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Endocrine Disruptor Vinclozolin Induced Epigenetic Transgenerational Adult-Onset Disease

    Science.gov (United States)

    Anway, Matthew D.; Leathers, Charles; Skinner, Michael K.

    2018-01-01

    The fetal basis of adult disease is poorly understood on a molecular level and cannot be solely attributed to genetic mutations or a single etiology. Embryonic exposure to environmental compounds has been shown to promote various disease states or lesions in the first generation (F1). The current study used the endocrine disruptor vinclozolin (antiandrogenic compound) in a transient embryonic exposure at the time of gonadal sex determination in rats. Adult animals from the F1 generation and all subsequent generations examined (F1–F4) developed a number of disease states or tissue abnormalities including prostate disease, kidney disease, immune system abnormalities, testis abnormalities, and tumor development (e.g. breast). In addition, a number of blood abnormalities developed including hypercholesterolemia. The incidence or prevalence of these transgenerational disease states was high and consistent across all generations (F1–F4) and, based on data from a previous study, appears to be due in part to epigenetic alterations in the male germ line. The observations demonstrate that an environmental compound, endocrine disruptor, can induce transgenerational disease states or abnormalities, and this suggests a potential epigenetic etiology and molecular basis of adult onset disease. PMID:16973726

  9. STEM Education.

    Science.gov (United States)

    Xie, Yu; Fang, Michael; Shauman, Kimberlee

    2015-08-01

    Improving science, technology, engineering, and mathematics (STEM) education, especially for traditionally disadvantaged groups, is widely recognized as pivotal to the U.S.'s long-term economic growth and security. In this article, we review and discuss current research on STEM education in the U.S., drawing on recent research in sociology and related fields. The reviewed literature shows that different social factors affect the two major components of STEM education attainment: (1) attainment of education in general, and (2) attainment of STEM education relative to non-STEM education conditional on educational attainment. Cognitive and social psychological characteristics matter for both major components, as do structural influences at the neighborhood, school, and broader cultural levels. However, while commonly used measures of socioeconomic status (SES) predict the attainment of general education, social psychological factors are more important influences on participation and achievement in STEM versus non-STEM education. Domestically, disparities by family SES, race, and gender persist in STEM education. Internationally, American students lag behind those in some countries with less economic resources. Explanations for group disparities within the U.S. and the mediocre international ranking of US student performance require more research, a task that is best accomplished through interdisciplinary approaches.

  10. Learn About Stem Cells

    Science.gov (United States)

    ... Patient Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... original cell’s DNA, cytoplasm and cell membrane. About stem cells Stem cells are the foundation of development in ...

  11. Expression of Pluripotency and Oocyte-Related Genes in Single Putative Stem Cells from Human Adult Ovarian Surface Epithelium Cultured In Vitro in the Presence of Follicular Fluid

    Directory of Open Access Journals (Sweden)

    Irma Virant-Klun

    2013-01-01

    Full Text Available The aim of this study was to trigger the expression of genes related to oocytes in putative ovarian stem cells scraped from the ovarian surface epithelium of women with premature ovarian failure and cultured in vitro in the presence of follicular fluid, rich in substances for oocyte growth and maturation. Ovarian surface epithelium was scraped and cell cultures were set up by scrapings in five women with nonfunctional ovaries and with no naturally present mature follicles or oocytes. In the presence of donated follicular fluid putative stem cells grew and developed into primitive oocyte-like cells. A detailed single-cell gene expression profiling was performed to elucidate their genetic status in comparison to human embryonic stem cells, oocytes, and somatic fibroblasts. The ovarian cell cultures depleted/converted reproductive hormones from the culture medium. Estradiol alone or together with other substances may be involved in development of these primitive oocyte-like cells. The majority of primitive oocyte-like cells was mononuclear and expressed several genes related to pluripotency and oocytes, including genes related to meiosis, although they did not express some important oocyte-specific genes. Our work reveals the presence of putative stem cells in the ovarian surface epithelium of women with premature ovarian failure.

  12. An expandable embryonic stem cell-derived Purkinje neuron progenitor population that exhibits in vivo maturation in the adult mouse cerebellum

    NARCIS (Netherlands)

    Higuera, Gustavo A; Iaffaldano, Grazia; Bedar, Meiwand; Shpak, Guy; Broersen, Robin; Munshi, Shashini T; Dupont, Catherine; Gribnau, Joost; de Vrij, Femke M S; Kushner, Steven A; De Zeeuw, Chris I

    2017-01-01

    The directed differentiation of patient-derived induced pluripotent stem cells into cell-type specific neurons has inspired the development of therapeutic discovery for neurodegenerative diseases. Many forms of ataxia result from degeneration of cerebellar Purkinje cells, but thus far it has not

  13. An expandable embryonic stem cell-derived Purkinje neuron progenitor population that exhibits in vivo maturation in the adult mouse cerebellum

    NARCIS (Netherlands)

    G.A. Higuera (Gustavo A.); Iaffaldano, G. (Grazia); Bedar, M. (Meiwand); G. Shpak (Guy); R. Broersen (Robin); S.T. Munshi (Shashini T.); Dupont, C. (Catherine); J.H. Gribnau (Joost); F.M.S. Vrij (Femke); S.A. Kushner (Steven); C.I. de Zeeuw (Chris)

    2017-01-01

    textabstractThe directed differentiation of patient-derived induced pluripotent stem cells into cell-type specific neurons has inspired the development of therapeutic discovery for neurodegenerative diseases. Many forms of ataxia result from degeneration of cerebellar Purkinje cells, but thus far it

  14. Stem Cell Therapies in Orthopaedic Trauma

    OpenAIRE

    Marcucio, Ralph S.; Nauth, Aaron; Giannoudis, Peter V.; Bahney, Chelsea; Piuzzi, Nicolas S.; Muschler, George; Miclau, Theodore

    2015-01-01

    Stem cells offer great promise to help understand the normal mechanisms of tissue renewal, regeneration, and repair, and also for development of cell-based therapies to treat patients after tissue injury. Most adult tissues contain stem cells and progenitor cells that contribute to homeostasis, remodeling and repair. Multiple stem and progenitor cell populations in bone are found in the marrow, the endosteum, and the periosteum. They contribute to the fracture healing process after injury and...

  15. Mesenchymal stem cells in oral reconstructive surgery

    DEFF Research Database (Denmark)

    Jakobsen, C; Sørensen, J A; Kassem, M

    2013-01-01

    This study evaluated clinical outcomes following intraoperative use of adult mesenchymal stem cells (MSCs) in various oral reconstructive procedures. PubMed was searched without language restrictions from 2000 to 2011 using the search words stem cell, oral surgery, tissue engineering, sinus lift...

  16. Stem cell facelift: between reality and fiction.

    Science.gov (United States)

    Atiyeh, Bishara S; Ibrahim, Amir E; Saad, Dibo A

    2013-03-01

    Stem cells are "big business" throughout medical technology, and their potential application in cosmetic procedures is no exception. One of the latest nonsurgical facial treatments (and new catchphrases) in plastic surgery is the "stem cell facelift." It is evident from the currently available scientific literature that the use of stem cell therapy for facial rejuvenation is limited to the theoretical induction of skin tightening and can in no way be equated to a facelift. In fact, what is advertised and promoted as a new and original technique of stem cell facelifting is mostly stem cell-enriched lipofilling. Despite encouraging data suggesting that adult stem cells hold promise for future applications, the data from clinical evidence available today do not substantiate the marketing and promotional claims being made to patients. To claim that the "stem cell facelift" is a complete facial rejuvenation procedure surgery is unethical.

  17. STEM Education

    Science.gov (United States)

    & Development (LDRD) National Security Education Center (NSEC) Office of Science Programs Richard P Databases National Security Education Center (NSEC) Center for Nonlinear Studies Engineering Institute Scholarships STEM Education Programs Teachers (K-12) Students (K-12) Higher Education Regional Education

  18. Paraneoplastic brain stem encephalitis.

    Science.gov (United States)

    Blaes, Franz

    2013-04-01

    Paraneoplastic brain stem encephalitis can occur as an isolated clinical syndrome or, more often, may be part of a more widespread encephalitis. Different antineuronal autoantibodies, such as anti-Hu, anti-Ri, and anti-Ma2 can be associated with the syndrome, and the most frequent tumors are lung and testicular cancer. Anti-Hu-associated brain stem encephalitis does not normally respond to immunotherapy; the syndrome may stabilize under tumor treatment. Brain stem encephalitis with anti-Ma2 often improves after immunotherapy and/or tumor therapy, whereas only a minority of anti-Ri positive patients respond to immunosuppressants or tumor treatment. The Opsoclonus-myoclonus syndrome (OMS) in children, almost exclusively associated with neuroblastoma, shows a good response to steroids, ACTH, and rituximab, some patients do respond to intravenous immunoglobulins or cyclophosphamide. In adults, OMS is mainly associated with small cell lung cancer or gynecological tumors and only a small part of the patients show improvement after immunotherapy. Earlier diagnosis and treatment seem to be one major problem to improve the prognosis of both, paraneoplastic brain stem encephalitis, and OMS.

  19. The pluripotency of hair follicle stem cells.

    Science.gov (United States)

    Hoffman, Robert M

    2006-02-01

    The hair follicle bulge area is an abundant, easily accessible source of actively growing, pluripotent adult stem cells. Nestin, a protein marker for neural stem cells, is also expressed in follicle stem cells as well as their immediate differentiated progeny. The nestin-expressing hair follicle stem cells differentiated into neurons, glial cells, keratinocytes and smooth muscle cells in vitro. Hair-follicle stem cells were implanted into the gap region of a severed sciatic nerve. The hair follicle stem cells greatly enhanced the rate of nerve regeneration and the restoration of nerve function. The follicle stem cells transdifferentiated largely into Schwann cells which are known to support neuron regrowth. Function of the rejoined sciatic nerve was measured by contraction of the gastrocnemius muscle upon electrical stimulation. After severing the tibial nerve and subsequent transplantation of hair-follicle stem cells, the transplanted mice recovered the ability to walk normally. These results suggest that hair-follicle stem cells provide an important accessible, autologous source of adult stem cells for regenerative medicine.

  20. Protein Kinase Cε, Which Is Linked to Ultraviolet Radiation-Induced Development of Squamous Cell Carcinomas, Stimulates Rapid Turnover of Adult Hair Follicle Stem Cells

    International Nuclear Information System (INIS)

    Singh, A.; Singh, A.; Sand, J. M.; Bin Hafeez, B.; Verma, A. K.; Sand, J. M.; Heninger, E.

    2013-01-01

    To find clues about the mechanism by which kinase C epsilon (PKCε) may impart susceptibility to ultraviolet radiation (UVR)-induced development of cutaneous squamous cell carcinomas (SCC), we compared PKCε transgenic (TG) mice and their wild-type (WT) litter mates for (1) the effects of UVR exposures on percent of putative hair follicle stem cells (HSC s ) and (2) HSCs proliferation. The percent of double HSC s (CD34+ andα6-integrin or CD34+/CD49f+) in the isolated keratinocytes were determined by flow cytometric analysis. Both single and chronic UVR treatments (1.8 kJ/m 2 ) resulted in an increase in the frequency of double positive HSCs in PKCεTG mice as compared to their WT litter mates. To determine the rate of proliferation of bulge region stem cells, a 5-bromo-2-deoxyuridine labeling (BrdU) experiment was performed. In the WT mice, the percent of double positive HSC s retaining BrdU label was 28.4±0.6% compared to 4.0±0.06% for the TG mice, an approximately 7-fold decrease. A comparison of gene expression profiles of FACS sorted double positive HSCs showed increased expression of Pes1, Rad21, Tfdp1 and Cks1b genes in TG mice compared to WT mice. Also, PKCεover expression in mice increased the clonogenicity of isolated keratinocytes, a property commonly ascribed to stem cells.

  1. Tissue-specific designs of stem cell hierarchies

    NARCIS (Netherlands)

    Visvader, Jane E.; Clevers, Hans

    2016-01-01

    Recent work in the field of stem cell biology suggests that there is no single design for an adult tissue stem cell hierarchy, and that different tissues employ distinct strategies to meet their self-renewal and repair requirements. Stem cells may be multipotent or unipotent, and can exist in

  2. Tissue-specific designs of stem cell hierarchies

    NARCIS (Netherlands)

    Visvader, Jane E; Clevers, Hans

    Recent work in the field of stem cell biology suggests that there is no single design for an adult tissue stem cell hierarchy, and that different tissues employ distinct strategies to meet their self-renewal and repair requirements. Stem cells may be multipotent or unipotent, and can exist in

  3. Stem Cells and Tissue Engineering

    CERN Document Server

    Pavlovic, Mirjana

    2013-01-01

    Stem cells are the building blocks for all other cells in an organism. The human body has about 200 different types of cells and any of those cells can be produced by a stem cell. This fact emphasizes the significance of stem cells in transplantational medicine, regenerative therapy and bioengineering. Whether embryonic or adult, these cells can be used for the successful treatment of a wide range of diseases that were not treatable before, such as osteogenesis imperfecta in children, different forms of leukemias, acute myocardial infarction, some neural damages and diseases, etc. Bioengineering, e.g. successful manipulation of these cells with multipotential capacity of differentiation toward appropriate patterns and precise quantity, are the prerequisites for successful outcome and treatment. By combining in vivo and in vitro techniques, it is now possible to manage the wide spectrum of tissue damages and organ diseases. Although the stem-cell therapy is not a response to all the questions, it provides more...

  4. Are the Polyomaviruses BK and JC Associated with Opportunistic Infections, Graft-versus-Host Disease, or Worse Outcomes in Adult Patients Receiving Their First Allogeneic Stem Cell Transplantation with Low-Dose Alemtuzumab?

    Science.gov (United States)

    Schneidewind, Laila; Neumann, Thomas; Knoll, Florian; Zimmermann, Kathrin; Smola, Sigrun; Schmidt, Christian Andreas; Krüger, William

    2017-01-01

    The association of polyomaviruses BK and JC with other opportunistic infections and graft-versus-host disease (GvHD) in allogeneic stem cell transplantation is controversially discussed. We conducted a retrospective study of 64 adult patients who received their first allogeneic stem cell transplantation between March 2010 and December 2014; the follow-up time was 2 years. Acute leukemia was the most frequent underlying disease (45.3%), and conditioning included myeloablative (67.2%) and nonmyeloablative protocols (32.8%). All patients received 10 mg of alemtuzumab on day -2 (20 mg in case of mismatch) as GvHD prophylaxis. Twenty-seven patients (41.5%) developed cytomegalovirus (CMV) reactivation. BKPyV-associated hemorrhagic cystitis was diagnosed in 10 patients (15.6%). Other opportunistic infections caused by viruses or protozoa occurred rarely (reactivation, Epstein-Barr virus reactivation, human herpes virus 6, or parvovirus B19 infection requiring treatment. There was a significant correlation of BKPyV-associated hemorrhagic cystitis with toxoplasmosis (p = 0.013). Additionally, there was a significant link of simultaneous BKPyV and JCPyV viruria with toxoplasmosis (p = 0.047). BKPyV and JCPyV were not associated with GvHD, relapse, or death. We found no association of BKPyV or JCPyV with viral infections or GvHD. Only the correlation of both polyomaviruses with toxoplasmosis was significant. This is a novel and interesting finding. © 2017 S. Karger AG, Basel.

  5. Identification of distinct topographical surface microstructures favoring either undifferentiated expansion or differentiation of murine embryonic stem cells.

    Science.gov (United States)

    Markert, Lotte D'Andrea; Lovmand, Jette; Foss, Morten; Lauridsen, Rune Hoff; Lovmand, Michael; Füchtbauer, Ernst-Martin; Füchtbauer, Annette; Wertz, Karin; Besenbacher, Flemming; Pedersen, Finn Skou; Duch, Mogens

    2009-11-01

    The potential of embryonic stem (ES) cells for both self-renewal and differentiation into cells of all three germ layers has generated immense interest in utilizing these cells for tissue engineering or cell-based therapies. However, the ability to culture undifferentiated ES cells without the use of feeder cells as well as means to obtain homogeneous, differentiated cell populations devoid of residual pluripotent ES cells still remain major challenges. Here we have applied murine ES cells to topographically microstructured surface libraries, BioSurface Structure Arrays (BSSA), and investigated whether these could be used to (i) identify topographically microstructured growth supports alleviating the need for feeder cells for expansion of undifferentiated ES cells and (ii) identify specific types of microstructures enforcing differentiation of ES cells. The BSSA surfaces arrays consisted of 504 different topographical microstructures each located in a tester field of 3 x 3 mm. The murine ES cell lines CJ7 and KH2 were seeded upon the BSSA libraries and specific topographical structures facilitating either undifferentiated ES cell growth or enhancing spreading indicative of differentiation of the ES cells were identified. Secondly serial passage of undifferentiated CJ7 ES cells on selected microstructures, identified in the screening of these BSSA libraries, showed that these cells had retained germ-line potential. These results indicate that one specific type of topographical surface microstructures, identified by the BSSA technology, can substitute for feeder cells and that another subset may be used to eliminate undifferentiated ES cells from a population of differentiated ES cells.

  6. Stem cells for tooth engineering

    Directory of Open Access Journals (Sweden)

    G Bluteau

    2008-07-01

    Full Text Available Tooth development results from sequential and reciprocal interactions between the oral epithelium and the underlying neural crest-derived mesenchyme. The generation of dental structures and/or entire teeth in the laboratory depends upon the manipulation of stem cells and requires a synergy of all cellular and molecular events that finally lead to the formation of tooth-specific hard tissues, dentin and enamel. Although mesenchymal stem cells from different origins have been extensively studied in their capacity to form dentin in vitro, information is not yet available concerning the use of epithelial stem cells. The odontogenic potential resides in the oral epithelium and thus epithelial stem cells are necessary for both the initiation of tooth formation and enamel matrix production. This review focuses on the different sources of stem cells that have been used for making teeth in vitro and their relative efficiency. Embryonic, post-natal or even adult stem cells were assessed and proved to possess an enormous regenerative potential, but their application in dental practice is still problematic and limited due to various parameters that are not yet under control such as the high risk of rejection, cell behaviour, long tooth eruption period, appropriate crown morphology and suitable colour. Nevertheless, the development of biological approaches for dental reconstruction using stem cells is promising and remains one of the greatest challenges in the dental field for the years to come.

  7. Stem cells: limitations and opportunities in Peru

    OpenAIRE

    Amiel-Pérez, José; Laboratorio de Cultivos Celulares, Universidad Científica del Sur. Lima, Perú.; Casado, Fanny; Stem Cell and Cancer Research Institute, McMaster University. Hamilton, Canadá.

    2015-01-01

    Stem cells are defined as rare cells that are characterized by asymmetric division, a process known as self-renewal, and the potential to differentiate into more than one type of terminally differentiated cell. There is a diversity of stem cells including embryonic stem cells, which exist only during the first stages of human development, and many adult stem cells depending on the specific tissues from where they derive or the ones derived from mesenchymal or stromal tissues. On the other han...

  8. Hardwiring Stem Cell Communication through Tissue Structure.

    Science.gov (United States)

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-03-10

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Hardwiring stem cell communication through tissue structure

    Science.gov (United States)

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-01-01

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. PMID:26967287

  10. Cancer stem cells and differentiation therapy.

    Science.gov (United States)

    Jin, Xiong; Jin, Xun; Kim, Hyunggee

    2017-10-01

    Cancer stem cells can generate tumors from only a small number of cells, whereas differentiated cancer cells cannot. The prominent feature of cancer stem cells is its ability to self-renew and differentiate into multiple types of cancer cells. Cancer stem cells have several distinct tumorigenic abilities, including stem cell signal transduction, tumorigenicity, metastasis, and resistance to anticancer drugs, which are regulated by genetic or epigenetic changes. Like normal adult stem cells involved in various developmental processes and tissue homeostasis, cancer stem cells maintain their self-renewal capacity by activating multiple stem cell signaling pathways and inhibiting differentiation signaling pathways during cancer initiation and progression. Recently, many studies have focused on targeting cancer stem cells to eradicate malignancies by regulating stem cell signaling pathways, and products of some of these strategies are in preclinical and clinical trials. In this review, we describe the crucial features of cancer stem cells related to tumor relapse and drug resistance, as well as the new therapeutic strategy to target cancer stem cells named "differentiation therapy."

  11. Are You Teaching Your Students about Stem Cells?

    Science.gov (United States)

    Concannon, James; Brown, Patrick L.; Brandt, Trisha

    2009-01-01

    This activity targets students' misconceptions about embryonic and adult stem cells while also addressing an important grades 9-12 science content standard. The authors designed the activity to provide students an opportunity to explore differences between embryonic and adult stem cells prior to formal explanation. The overarching goal of this…

  12. Facts about Stem Cells and Importance of Them

    Directory of Open Access Journals (Sweden)

    Masumeh Saeidi

    2014-05-01

    Full Text Available Stem cells are undifferentiated biological cells that can differentiate into specialized cells and can divide (through mitosis to produce more stem cells. They are found in multicellular organisms. In mammals, there are two broad types of stem cells: embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing adult tissues. In a developing embryo, stem cells can differentiate into all the specialized cells—ectoderm, endoderm and mesoderm (see induced pluripotent stem cells—but also maintain the normal turnover of regenerative organs, such as blood, skin, or intestinal tissues. There are three accessible sources of autologous adult stem cells in humans: Bone marrow, which requires extraction by harvesting, that is, drilling into bone (typically the femur or iliac crest, Adipose tissue (lipid cells, which requires extraction by liposuction, and Blood, which requires extraction through apheresis, wherein blood is drawn from the donor (similar to a blood donation, and passed through a machine that extracts the stem cells and returns other portions of the blood to the donor. Stem cells can also be taken from umbilical cord blood just after birth. Of all stem cell types, autologous harvesting involves the least risk. By definition, autologous cells are obtained from one's own body, just as one may bank his or her own blood for elective surgical procedures. Adult stem cells are frequently used in medical therapies, for example in bone marrow transplantation. Stem cells can now be artificially grown and transformed (differentiated into specialized cell types with characteristics consistent with cells of various tissues such as muscles or nerves. Embryonic cell lines and autologous embryonic stem cells generated through Somatic-cell nuclear transfer or dedifferentiation

  13. Stem Cell Basics

    Science.gov (United States)

    ... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... Basics » Stem Cell Basics I. Back to top Stem Cell Basics I. Introduction: What are stem cells, and ...

  14. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    In his influential essay on markets, An essay on framing and overflowing (1998), Michel Callon writes that `the growing complexity of industrialized societies [is] due in large part to the movements of the technosciences, which are causing connections and interdependencies to proliferate'. This p...... and tantalizing than stem cells, in research, in medicine, or as products.......'. This paper is about tech-noscience, and about the proliferation of connections and interdependencies created by it.More specifically, the paper is about stem cells. Biotechnology in general has the power to capture the imagination. Within the field of biotechnology nothing seems more provocative...

  15. Stem Cell Therapy: An emerging science

    International Nuclear Information System (INIS)

    Khan, Muhammad M.

    2007-01-01

    The research on stem cells is advancing knowledge about the development of an organism from a single cell and to how healthy cells replace damaged cells in adult organisms. Stem cell therapy is emerging rapidly nowadays as a technical tool for tissue repair and replacement. The purpose of this review to provide a framework of understanding for the challenges behind translating fundamental stem cell biology and its potential use into clinical therapies, also to give an overview on stem cell research to the scientists of Saudi Arabia in general. English language MEDLINE publications from 1980 through January 2007 for experimental, observational and clinical studies having relation with stem cells with different diseases were reviewed. Approximately 85 publications were reviewed based on the relevance, strength and quality of design and methods, 36 publications were selected for inclusion. Stem cells reside in a specific area of each tissue where they may remain undivided for several years until they are activated by disease or tissue injury. The embryonic stem cells are typically derived from four or five days old embryos and they are pluripotent. The adult tissues reported to contain stem cells brain, bone marrow, peripheral blood, blood vessels, skeletal muscle, skin and liver. The promise of stem cell therapies is an exciting one, but significant technical hurdles remain that will only be overcome through years of intensive research. (author)

  16. Transformation of intestinal stem cells into gastric stem cells on loss of transcription factor Cdx2

    NARCIS (Netherlands)

    Simmini, Salvatore; Bialecka, Monika; Huch, Meritxell; Kester, Lennart; van de Wetering, Marc; Sato, Toshiro; Beck, Felix; van Oudenaarden, Alexander; Clevers, Hans; Deschamps, Jacqueline

    2014-01-01

    The endodermal lining of the adult gastro-intestinal tract harbours stem cells that are responsible for the day-to-day regeneration of the epithelium. Stem cells residing in the pyloric glands of the stomach and in the small intestinal crypts differ in their differentiation programme and in the gene

  17. Strategies for future histocompatible stem cell therapy

    DEFF Research Database (Denmark)

    Nehlin, Jan; Barington, Torben

    2009-01-01

    Stem cell therapy based on the safe and unlimited self-renewal of human pluripotent stem cells is envisioned for future use in tissue or organ replacement after injury or disease. A gradual decline of regenerative capacity has been documented among the adult stem cell population in some body organs...... during the aging process. Recent progress in human somatic cell nuclear transfer and inducible pluripotent stem cell technologies has shown that patient-derived nuclei or somatic cells can be reprogrammed in vitro to become pluripotent stem cells, from which the three germ layer lineages can be generated......, genetically identical to the recipient. Once differentiation protocols and culture conditions can be defined and optimized, patient-histocompatible pluripotent stem cells could be directed towards virtually every cell type in the human body. Harnessing this capability to enrich for given cells within...

  18. Of Microenvironments and Mammary Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    LaBarge, Mark A; Petersen, Ole W; Bissell, Mina J

    2007-06-01

    In most adult tissues there reside pools of stem and progenitor cells inside specialized microenvironments referred to as niches. The niche protects the stem cells from inappropriate expansion and directs their critical functions. Thus guided, stem cells are able to maintain tissue homeostasis throughout the ebb and flow of metabolic and physical demands encountered over a lifetime. Indeed, a pool of stem cells maintains mammary gland structure throughout development, and responds to the physiological demands associated with pregnancy. This review discusses how stem cells were identified in both human and mouse mammary glands; each requiring different techniques that were determined by differing biological needs and ethical constraints. These studies together create a robust portrait of mammary gland biology and identify the location of the stem cell niche, elucidate a developmental hierarchy, and suggest how the niche might be manipulated for therapeutic benefit.

  19. Stem Cells and Herbal Acupuncture Therapy

    Directory of Open Access Journals (Sweden)

    Ki Rok Kwon

    2005-12-01

    Full Text Available Stem cell therapy implies the birth of regenerative medicine. Regenerative medicine signify treatment through regeneration of cells which was impossible by existing medicine. Stem cell is classified into embryonic stem cell and adult stem cell and they have distinctive benefits and limitations. Researches on stem cell are already under active progression and is expected to be commercially available in the near future. One may not relate the stem cell treatment with Oriental medicine, but can be interpreted as the fundamental treatment action of Oriental medicine is being investigated in more concrete manner. When it comes to difficult to cure diseases, there is no boundary between eastern and western medicine, and one must be ready to face and overcome changes lying ahead.

  20. Stem cells: sources and therapies

    Directory of Open Access Journals (Sweden)

    Manuela Monti

    2012-01-01

    Full Text Available The historical, lexical and conceptual issues embedded in stem cell biology are reviewed from technical, ethical, philosophical, judicial, clinical, economic and biopolitical perspectives. The mechanisms assigning the simultaneous capacity to self-renew and to differentiate to stem cells (immortal template DNA and asymmetric division are evaluated in the light of the niche hypothesis for the stemness state. The induction of cell pluripotency and the different stem cells sources are presented (embryonic, adult and cord blood. We highlight the embryonic and adult stem cell properties and possible therapies while we emphasize the particular scientific and social values of cord blood donation to set up cord blood banks. The current scientific and legal frameworks of cord blood banks are reviewed at an international level as well as allogenic, dedicated and autologous donations. The expectations and the challenges in relation to present-day targeted diseases like diabetes mellitus type I, Parkinson's disease and myocardial infarction are evaluated in the light of the cellular therapies for regenerative medicine.

  1. Stem cells from birth to death : The history and the future

    NARCIS (Netherlands)

    de Haan, G; Van Zant, G

    The concept that adult stem cells, despite their impressive proliferative potential, are immortal has been challenged by experimental studies of hematopoietic stem cells. In this review, we discuss the properties that characterize a stem cell, the growing list of tissues in which stem cells are

  2. Why STEM?

    Science.gov (United States)

    Mitts, Charles R.

    2016-01-01

    The International Technology and Engineering Educators Association (ITEEA) defines STEM as a new transdisciplinary subject in schools that integrates the disciplines of science, technology, engineering, and mathematics into a single course of study. There are three major problems with this definition: There is no consensus in support of the ITEEA…

  3. Correction of mouse ornithine transcarbamylase deficiency by gene transfer into the germ line

    Energy Technology Data Exchange (ETDEWEB)

    Cavard, C; Grimber, G; Dubois, N; Chasse, J F; Bennoun, M; Minet-Thuriaux, M; Kamoun, P; Briand, P

    1988-03-25

    The sparse fur with abnormal skin and hair (Spf-ash) mouse is a model for the human x-linked hereditary disorder, ornithine transcarbamylase (OTC) deficiency. In Spf-ash mice, both OTC mRNA and enzyme activity are 5% of control values resulting in hyperammonemia, pronounced orotic aciduria and an abnormal phenotype characterized by growth retardation and sparse fur. Using microinjection, the authors introduced a construction containing rat OTC cDNA linked to the SV40 early promoter into fertilized eggs of Spf-ash mice. The expression of the transgene resulted in the development of a transgenic mouse whose phenotype and orotic acid excretion are fully normalized. Thus, the possibility of correcting hereditary enzymatic defect by gene transfer of heterologous cDNA coding for the normal enzyme has been demonstrated.

  4. [About the infection of Drosophila female germ line cells by sigma virus (author's transl)].

    Science.gov (United States)

    Brun, G

    1977-01-01

    The results which have been presented by Bregliano (1973) and Bregliano et Fleuriet (1975) in this "Annales" are discussed. The author's conclusion is that there are two distinct mechanisms for contamination of the cysts of non-stabilized females (in stabilized females, all cells, including oogonial cells, are infected in carrier state by sigma). Hypotheses are discussed.

  5. Identification of 3 novel VHL germ-line mutations in Danish VHL patients

    DEFF Research Database (Denmark)

    Dandanell, Mette; Friis-Hansen, Lennart Jan; Sunde, Lone

    2012-01-01

    von Hippel-Lindau (VHL) disease is a hereditary cancer syndrome in which the patients develop retinal and central nervous system hemangioblastomas, pheochromocytomas and clear-cell renal tumors. The autosomal dominant disease is caused by mutations in the VHL gene.......von Hippel-Lindau (VHL) disease is a hereditary cancer syndrome in which the patients develop retinal and central nervous system hemangioblastomas, pheochromocytomas and clear-cell renal tumors. The autosomal dominant disease is caused by mutations in the VHL gene....

  6. Maternal age effect and severe germ-line bottleneck in the inheritance of human mitochondrial DNA

    DEFF Research Database (Denmark)

    Rebolledo-Jaramillo, Boris; Su, Marcia Shu-Wei; Stoler, Nicholas

    2014-01-01

    The manifestation of mitochondrial DNA (mtDNA) diseases depends on the frequency of heteroplasmy (the presence of several alleles in an individual), yet its transmission across generations cannot be readily predicted owing to a lack of data on the size of the mtDNA bottleneck during oogenesis......, an order of magnitude higher than for nuclear DNA. Notably, we found a positive association between the number of heteroplasmies in a child and maternal age at fertilization, likely attributable to oocyte aging. This study also took advantage of droplet digital PCR (ddPCR) to validate heteroplasmies...... and confirm a de novo mutation. Our results can be used to predict the transmission of disease-causing mtDNA variants and illuminate evolutionary dynamics of the mitochondrial genome....

  7. Retrovirus-mediated in vitro gene transfer into chicken male germ line cells

    Czech Academy of Sciences Publication Activity Database

    Kalina, J.; Šenigl, Filip; Mičáková, A.; Mucksová, J.; Blažková, Jana; Haifeng, Y.; Poplštejn, M.; Hejnar, Jiří; Trefil, P.

    2007-01-01

    Roč. 134, č. 3 (2007), s. 445-453 ISSN 1470-1626 R&D Projects: GA ČR GA523/04/0569 Grant - others:GA MŠk(CZ) 1P05ME722 Institutional research plan: CEZ:AV0Z50520514 Keywords : Transgenic spermatozoa * infection of testicular cells with retrovirus * transgenesis in chicken Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.962, year: 2007

  8. Mismatch repair deficiency does not enhance ENU mutagenesis in the zebrafish germ line.

    NARCIS (Netherlands)

    Feitsma, H.; de Bruijn, E.; van de Belt, J.; Nijman, I.J.; Cuppen, E.

    2008-01-01

    S(N)1-type alkylating agents such as N-ethyl-N-nitrosourea (ENU) are very potent mutagens. They act by transferring their alkyl group to DNA bases, which, upon mispairing during replication, can cause single base pair mutations in the next replication cycle. As DNA mismatch repair (MMR) proteins are

  9. Germ-line mutations at a mouse ESTR (Pc-3) locus and human microsatellite loci

    International Nuclear Information System (INIS)

    Ryo, Haruko; Nakajima, Hiroo; Nomura, Taisei

    2006-01-01

    We examined the use of the mouse Pc-3 ESTR (expanded simple tandem repeat) locus and 72 human microsatellite loci as potentially sensitive biomarkers for mutagenic exposures to germ cells in mice and humans respectively. In the mouse work, we treated male mice with TCDD (2, 3, 7, 8-tetrachlo-rodibenzo-p-dioxin; a chemical known to induce congenital anomalies in humans and mice) and, analysed the F 1 fetuses for Pc-3 mutations. Although the incidence of anomalies was higher in the TCDD group, there were no induced mutations. However, respiratory distress syndrome (RDS) was observed in 3 of 7 fetuses born to male mice which were treated with TCDD and which showed abnormal length of Pc-3 allele. In the human studies, the children of Chernobyl liquidators were examined for mutations at a total of 72 (31 autosomal, 1 X-linked and 40 Y-linked) microsatellite loci. This study was prompted by earlier findings of increases in microsatellite mutations in barn swallows and wheat in the highly contaminated areas after the Chernobyl accident. We examined 64 liquidator families (70 children) and 66 control families (70 children). However, no increases in mutation rates were found. The estimated mean dose to the liquidators was about 39 mSv and this might be one possible reason why no increases of mutations could be found. (author)

  10. Disrupting the male germ line to find infertility and contraception targets.

    Science.gov (United States)

    Archambeault, Denise R; Matzuk, Martin M

    2014-05-01

    Genetically-manipulated mouse models have become indispensible for broadening our understanding of genes and pathways related to male germ cell development. Until suitable in vitro systems for studying spermatogenesis are perfected, in vivo models will remain the gold standard for inquiry into testicular function. Here, we discuss exciting advances that are allowing researchers faster, easier, and more customizable access to their mouse models of interest. Specifically, the trans-NIH Knockout Mouse Project (KOMP) is working to generate knockout mouse models of every gene in the mouse genome. The related Knockout Mouse Phenotyping Program (KOMP2) is performing systematic phenotypic analysis of this genome-wide collection of knockout mice, including fertility screening. Together, these programs will not only uncover new genes involved in male germ cell development but also provide the research community with the mouse models necessary for further investigations. In addition to KOMP/KOMP2, another promising development in the field of mouse models is the advent of CRISPR (clustered regularly interspaced short palindromic repeat)-Cas technology. Utilizing 20 nucleotide guide sequences, CRISPR/Cas has the potential to introduce sequence-specific insertions, deletions, and point mutations to produce null, conditional, activated, or reporter-tagged alleles. CRISPR/Cas can also successfully target multiple genes in a single experimental step, forgoing the multiple generations of breeding traditionally required to produce mouse models with deletions, insertions, or mutations in multiple genes. In addition, CRISPR/Cas can be used to create mouse models carrying variants identical to those identified in infertile human patients, providing the opportunity to explore the effects of such mutations in an in vivo system. Both the KOMP/KOMP2 projects and the CRISPR/Cas system provide powerful, accessible genetic approaches to the study of male germ cell development in the mouse. A more complete understanding of male germ cell biology is critical for the identification of novel targets for potential non-hormonal contraceptive intervention. Copyright © 2014. Published by Elsevier Masson SAS.

  11. Major haplotype divergence including multiple germin-like protein genes, at the wheat Sr2 adult plant stem rust resistance locus

    Czech Academy of Sciences Publication Activity Database

    Mago, R.; Tabe, L.; Vautrin, S.; Šimková, Hana; Kubaláková, Marie; Upadhyaya, N.; Berges, H.; Kong, X.Y.; Breen, J.; Doležel, Jaroslav; Appels, R.; Ellis, J.G.; Spielmeyer, W.

    2014-01-01

    Roč. 14, č. 379 (2014) ISSN 1471-2229 R&D Projects: GA ČR GBP501/12/G090; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Adult plant resistance (APR) * Map-based cloning * Sr2 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.813, year: 2014

  12. The biochemistry of hematopoietic stem cell development

    NARCIS (Netherlands)

    P. Kaimakis (Polynikis); M. Crisan (Mihaela); E.A. Dzierzak (Elaine)

    2013-01-01

    textabstractBackground: The cornerstone of the adult hematopoietic system and clinical treatments for blood-related disease is the cohort of hematopoietic stem cells (HSC) that is harbored in the adult bone marrow microenvironment. Interestingly, this cohort of HSCs is generated only during a short

  13. Keeping stem cells under control: new insights into the mechanisms that limit niche-stem cell signaling within the reproductive system

    OpenAIRE

    Inaba, Mayu; Yamashita, Yukiko M.; Buszczak, Michael

    2016-01-01

    Adult stem cells reside in specialized microenvironments called niches that maintain stem cells in an undifferentiated and self-renewing state. Despite extensive studies on the signaling pathways that operate within stem cells and their niches, the mechanisms that restrict niche signal exclusively to stem cells remained elusive: such a mechanism is crucially important to ensure that stem cells undergo self-renewal while their progeny, often located just one cell diameter away from the niche, ...

  14. Telomere stability and telomerase in mesenchymal stem cells

    DEFF Research Database (Denmark)

    Serakinci, Nedime; Graakjaer, Jesper; Kølvrå, Steen

    2008-01-01

    Telomeres are repetitive genetic material that cap and thereby protect the ends of chromosomes. Each time a cell divides, telomeres get shorter. Telomere length is mainly maintained by telomerase. This enzyme is present in high concentrations in the embryonic stem cells and in fast growing...... embryonic cells, and declines with age. It is still unclear to what extent there is telomerase in adult stem cells, but since these are the founder cells of cells of all the tissues in the body, understanding the telomere dynamics and expression of telomerase in adult stem cells is very important....... In the present communication we focus on telomere expression and telomere length in stem cells, with a special focus on mesenchymal stem cells. We consider different mechanisms by which stem cells can maintain telomeres and also focus on the dynamics of telomere length in mesenchymal stem cells, both the overall...

  15. An allograft generated from adult stem cells and their secreted products efficiently fuses vertebrae in immunocompromised athymic rats and inhibits local immune responses.

    Science.gov (United States)

    Clough, Bret H; McNeill, Eoin P; Palmer, Daniel; Krause, Ulf; Bartosh, Thomas J; Chaput, Christopher D; Gregory, Carl A

    2017-03-01

    Spine pain and the disability associated with it are epidemic in the United States. According to the National Center for Health Statistics, more than 650,000 spinal fusion surgeries are performed annually in the United States, and yet there is a failure rate of 15%-40% when standard methods employing current commercial bone substitutes are used. Autologous bone graft is the gold standard in terms of fusion success, but the morbidity associated with the procedure and the limitations in the availability of sufficient material have limited its use in the majority of cases. A freely available and immunologically compatible bone mimetic with the properties of live tissue is likely to substantially improve the outcome of spine fusion procedures without the disadvantages of autologous bone graft. This study aimed to compare a live human bone tissue analog with autologous bone grafting in an immunocompromised rat model of posterolateral fusion. This is an in vitro and in vivo preclinical study of a novel human stem cell-derived construct for efficacy in posterolateral lumbar spine fusion. Osteogenically enhanced human mesenchymal stem cells (OEhMSCs) were generated by exposure to conditions that activate the early stages of osteogenesis. Immunologic characteristics of OEhMSCs were evaluated in vitro. The secreted extracellular matrix from OEhMSCs was deposited on a clinical-grade gelatin sponge, resulting in bioconditioned gelatin sponge (BGS). Bioconditioned gelatin sponge was used alone, with live OEhMSCs (BGS+OEhMSCs), or with whole human bone marrow (BGS+hBM). Efficacy for spine fusion was determined by an institutionally approved animal model using 53 nude rats. Bioconditioned gelatin sponge with live OEhMSCs did not cause cytotoxicity when incubated with immunologically mismatched lymphocytes, and OEhMSCs inhibited lymphocyte expansion in mixed lymphocyte assays. Bioconditioned gelatin sponge with live OEhMSC and BGS+hBM constructs induced profound bone growth at

  16. When stem cells grow old: phenotypes and mechanisms of stem cell aging

    Science.gov (United States)

    Schultz, Michael B.; Sinclair, David A.

    2016-01-01

    All multicellular organisms undergo a decline in tissue and organ function as they age. An attractive theory is that a loss in stem cell number and/or activity over time causes this decline. In accordance with this theory, aging phenotypes have been described for stem cells of multiple tissues, including those of the hematopoietic system, intestine, muscle, brain, skin and germline. Here, we discuss recent advances in our understanding of why adult stem cells age and how this aging impacts diseases and lifespan. With this increased understanding, it is feasible to design and test interventions that delay stem cell aging and improve both health and lifespan. PMID:26732838

  17. Embryos, Clones, and Stem Cells: A Scientific Primer

    Directory of Open Access Journals (Sweden)

    Kenyon S. Tweedell

    2004-01-01

    Full Text Available This article is intended to give the nonspecialist an insight into the nuances of “clones”, cloning, and stem cells. It distinguishes embryonic and adult stem cells, their normal function in the organism, their origin, and how they are recovered to produce stem cell lines in culture. As background, the fundamental processes of embryo development are reviewed and defined, since the manipulation of stem cell lines into desired specialized cells employs many of the same events. Stem cells are defined and characterized and shown how they function in the intact organism during early development and later during cell regeneration in the adult. The complexity of stem cell recovery and their manipulation into specific cells and tissue is illustrated by reviewing current experimentation on both embryonic and adult stem cells in animals and limited research on human stem cell lines. The current and projected use of stem cells for human diseases and repair, along with the expanding methodology for the recovery of human embryonic stem cells, is described. An assessment on the use of human embryonic stem cells is considered from ethical, legal, religious, and political viewpoints.

  18. Normal karyotype mosaicism in adult AML patients with adverse-risk and undefined karyotype: preliminary report of treatment outcomes after hematopoietic stem cell transplantation.

    Science.gov (United States)

    Yoon, Jae-Ho; Kim, Hee-Je; Shin, Seung-Hwan; Yahng, Seung-Ah; Cho, Byung-Sik; Eom, Ki-Seong; Kim, Yoo-Jin; Lee, Seok; Min, Chang-Ki; Cho, Seok-Goo; Kim, Dong-Wook; Lee, Jong-Wook; Min, Woo-Sung; Park, Chong-Won

    2013-06-01

    Karyotype analysis in acute myeloid leukemia (AML) is one of the powerful prognostic factors for complete remission (CR), relapse, and overall survival (OS). Cytogenetic mosaicism is considered to be one of the important characteristics in expression of phenotypic manifestations. However, it has not come into focus due to emerging molecular biological approaches and the results of a number of mutation studies. Clinical correlates and prognostic relevance of mosaicism were evaluated in 163 AML patients [adverse-risk karyotypes (n = 72) and undefined karyotypes (n = 91)]. All patients were treated by induction and consolidation chemotherapies and finally went on hematopoietic stem cell transplantations (HSCT). Patients were divided into two subgroups, either with or without normal karyotype (NK) mosaicism. Seventy patients exhibited NK mosaicism and 93 did not. There were no significant differences in age, gender, chemotherapy cycles to achieve CR, HSCT donor type, source or intensity properties between the two subgroups. We found that NK mosaicism remaining in adverse-risk and undefined karyotype at diagnosis significantly correlates with better OS (p = 0.001) and lower CIR (p = 0.021) rate after HSCT. Our data show that the poor prognostic properties of unfavorable risk karyotype can be overcome to a great extent by allogeneic HSCT and chronic GVHD, especially in the subgroup with NK mosaicism. Cytogenetic mosaicism at initial diagnosis can be an influential factor for survival outcomes, even after HSCT.

  19. Stem cell biobanks.

    Science.gov (United States)

    Bardelli, Silvana

    2010-04-01

    Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment.

  20. Legislation governing pluripotent stem cells in South Africa

    Directory of Open Access Journals (Sweden)

    Michael Pepper

    2015-09-01

    Full Text Available One of the most exciting areas of medical research involves the use of stem cells for the treatment of patients with a variety of diseases and for tissue repair. Although stem cell research is accelerating rapidly in many countries, it has in the past been limited in South Africa (SA; very little has been done in this country to explore the great potential offered by stem cells to address the high disease burden. Stem cell therapy has however been practised for many years, in SA and worldwide, in the form of haematopoietic stem cell transplantation, mainly for haematological malignancies. From a therapeutic perspective, two types of stem cells can be defined: pluripotent stem cells and adult stem cells. Pluripotent cells derived from the inner cell mass of blastocysts (either from in vitro fertilisation or following somatic cell nuclear transfer are called embryonic stem (ES cells, while those derived by reprogramming adult cells are called induced pluripotent stem (iPS cells. Adult stem cells include haematopoietic, mesenchymal and neural stem cells.The purpose of this article is to critically examine the SA legislation with regard to elements that impact on pluripotent stem cell research and the use of pluripotent stem cells for therapeutic purposes. This includes (but is not limited to legislation from the National Health Act (Chapter 8 in particular and its regulations, and deals with matters related to research on embryos in the stem cell context, somatic cell nuclear transfer, reproductive and therapeutic cloning and the generation and therapeutic use of iPS and ES cells.

  1. [Bioethical challenges of stem cell tourism].

    Science.gov (United States)

    Ventura-Juncá, Patricio; Erices, Alejandro; Santos, Manuel J

    2013-08-01

    Stem cells have drawn extraordinary attention from scientists and the general public due to their potential to generate effective therapies for incurable diseases. At the same time, the production of embryonic stem cells involves a serious ethical issue concerning the destruction of human embryos. Although adult stem cells and induced pluripotential cells do not pose this ethical objection, there are other bioethical challenges common to all types of stem cells related particularly to the clinical use of stem cells. Their clinical use should be based on clinical trials, and in special situations, medical innovation, both of which have particular ethical dimensions. The media has raised unfounded expectations in patients and the public about the real clinical benefits of stem cells. At the same time, the number of unregulated clinics is increasing around the world, making direct offers through Internet of unproven stem cell therapies that attract desperate patients that have not found solutions in standard medicine. This is what is called stem cells tourism. This article reviews this situation, its consequences and the need for international cooperation to establish effective regulations to prevent the exploitation of patients and to endanger the prestige of legitimate stem cell research.

  2. Presenilins are required for maintenance of neural stem cells in the developing brain

    Directory of Open Access Journals (Sweden)

    Kim Woo-Young

    2008-01-01

    Full Text Available Abstract The early embryonic lethality of mutant mice bearing germ-line deletions of both presenilin genes precluded the study of their functions in neural development. We therefore employed the Cre-loxP technology to generate presenilin conditional double knockout (PS cDKO mice, in which expression of both presenilins is inactivated in neural progenitor cells (NPC or neural stem cells and their derivative neurons and glia beginning at embryonic day 11 (E11. In PS cDKO mice, dividing NPCs labeled by BrdU are decreased in number beginning at E13.5. By E15.5, fewer than 20% of NPCs remain in PS cDKO mice. The depletion of NPCs is accompanied by severe morphological defects and hemorrhages in the PS cDKO embryonic brain. Interkinetic nuclear migration of NPCs is also disrupted in PS cDKO embryos, as evidenced by displacement of S-phase and M-phase nuclei in the ventricular zone of the telencephalon. Furthermore, the depletion of neural progenitor cells in PS cDKO embryos is due to NPCs exiting cell cycle and differentiating into neurons rather than reentering cell cycle between E13.5 and E14.5 following PS inactivation in most NPCs. The length of cell cycle, however, is unchanged in PS cDKO embryos. Expression of Notch target genes, Hes1 and Hes5, is significantly decreased in PS cDKO brains, whereas Dll1 expression is up-regulated, indicating that Notch signaling is effectively blocked by PS inactivation. These findings demonstrate that presenilins are essential for neural progenitor cells to re-enter cell cycle and thus ensure proper expansion of neural progenitor pool during embryonic neural development.

  3. Identification of Abnormal Stem Cells Using Raman Spectroscopy

    DEFF Research Database (Denmark)

    Harkness, Linda; Novikov, Sergey M; Beermann, Jonas

    2012-01-01

    The clinical use of stem cells in cell-based therapeutics for degenerative diseases requires development of criteria for defining normal stem cells to ensure safe transplantation. Currently, identification of abnormal from normal stem cells is based on extensive ex vivo and in vivo testing. Raman...... microscopy is a label-free method for rapid and sensitive detection of changes in cells' bio-molecular composition. Here, we report that by using Raman spectroscopy, we were able to map the distribution of different biomolecules within 2 types of stem cells: adult human bone marrow-derived stromal stem cells...... and human embryonic stem cells and to identify reproducible differences in Raman's spectral characteristics that distinguished genetically abnormal and transformed stem cells from their normal counterparts. Raman microscopy can be prospectively employed as a method for identifying abnormal stem cells in ex...

  4. Regenerating the injured kidney with human umbilical cord mesenchymal stem cell-derived exosomes

    OpenAIRE

    Dorronsoro, Akaitz; Robbins, Paul D

    2013-01-01

    Transplantation of adult stem cells is being used to facilitate repair or regeneration of damaged or diseased tissues. However, in many cases, the therapeutic effects of the injected stem cells are mediated by factors secreted by stem cells and not by differentiation of the transplanted stem cells. Recent reports have identified a class of microvesicles, termed exosomes, released by stem cells that are able to confer therapeutic effects on injured renal and cardiac tissue. In this issue of St...

  5. Implanted hair follicle stem cells form Schwann cells that support repair of severed peripheral nerves

    OpenAIRE

    Amoh, Yasuyuki; Li, Lingna; Campillo, Raul; Kawahara, Katsumasa; Katsuoka, Kensei; Penman, Sheldon; Hoffman, Robert M.

    2005-01-01

    The hair follicle bulge area is an abundant, easily accessible source of actively growing, pluripotent adult stem cells. Nestin, a protein marker for neural stem cells, also is expressed in follicle stem cells and their immediate, differentiated progeny. The fluorescent protein GFP, whose expression is driven by the nestin regulatory element in transgenic mice, served to mark the follicle cell fate. The pluripotent nestin-driven GFP stem cells are positive for the stem cell marker CD34 but ne...

  6. Translating stem cell therapies: the role of companion animals in regenerative medicine

    OpenAIRE

    Volk, Susan W.; Theoret, Christine

    2013-01-01

    Veterinarians and veterinary medicine have been integral to the development of stem cell therapies. The contributions of large animal experimental models to the development and refinement of modern hematopoietic stem cell transplantation were noted nearly five decades ago. More recent advances in adult stem cell/regenerative cell therapies continue to expand knowledge of the basic biology and clinical applications of stem cells. A relatively liberal legal and ethical regulation of stem cell r...

  7. Tumourigenicity and radiation resistance of mesenchymal stem cells

    DEFF Research Database (Denmark)

    D'Andrea, Filippo Peder; Horsman, Michael Robert; Kassem, Moustapha

    2012-01-01

    Background. Cancer stem cells are believed to be more radiation resistant than differentiated tumour cells of the same origin. It is not known, however, whether normal nontransformed adult stem cells share the same radioresistance as their cancerous counterpart. Material and methods....... Nontumourigenic (TERT4) and tumourigenic (TRET20) cell lines, from an immortalised mesenchymal stem cell line, were grown in culture prior to irradiation and gene expression analysis. Radiation resistance was measured using a clonogenic assay. Differences in gene expression between the two cell lines, both under...... the intercellular matrix. These results also indicate that cancer stem cells are more radiation resistant than stem cells of the same origin....

  8. Induced Pluripotent Stem Cells for Regenerative Medicine

    OpenAIRE

    Hirschi, Karen K.; Li, Song; Roy, Krishnendu

    2014-01-01

    With the discovery of induced pluripotent stem (iPS) cells, it is now possible to convert differentiated somatic cells into multipotent stem cells that have the capacity to generate all cell types of adult tissues. Thus, there is a wide variety of applications for this technology, including regenerative medicine, in vitro disease modeling, and drug screening/discovery. Although biological and biochemical techniques have been well established for cell reprogramming, bioengineering technologies...

  9. Biophysical regulation of stem cell differentiation.

    Science.gov (United States)

    Govey, Peter M; Loiselle, Alayna E; Donahue, Henry J

    2013-06-01

    Bone adaptation to its mechanical environment, from embryonic through adult life, is thought to be the product of increased osteoblastic differentiation from mesenchymal stem cells. In parallel with tissue-scale loading, these heterogeneous populations of multipotent stem cells are subject to a variety of biophysical cues within their native microenvironments. Bone marrow-derived mesenchymal stem cells-the most broadly studied source of osteoblastic progenitors-undergo osteoblastic differentiation in vitro in response to biophysical signals, including hydrostatic pressure, fluid flow and accompanying shear stress, substrate strain and stiffness, substrate topography, and electromagnetic fields. Furthermore, stem cells may be subject to indirect regulation by mechano-sensing osteocytes positioned to more readily detect these same loading-induced signals within the bone matrix. Such paracrine and juxtacrine regulation of differentiation by osteocytes occurs in vitro. Further studies are needed to confirm both direct and indirect mechanisms of biophysical regulation within the in vivo stem cell niche.

  10. Igf2-H19, an imprinted tandem gene, is an important regulator of embryonic development, a guardian of proliferation of adult pluripotent stem cells, a regulator of longevity, and a ‘passkey’ to cancerogenesis

    Directory of Open Access Journals (Sweden)

    Mariusz Z. Ratajczak

    2012-07-01

    Full Text Available The insulin-like growth factor-2 (Igf2-H19 locus encodes important paternally imprinted genes that govern normal embryonic development. While Igf-2 encodes IGF2, which is an autocrine/paracrine mitogen,  transcription of H19 gives rise to non-coding mRNA that is a precursor of several microRNAs (miRNAs that negatively affect cell proliferation. The proper imprinting of a differentially methylated region (DMR within this locus, with methylation of the paternal chromosome and a lack of methylation on the maternal chromosome, regulates expression of both of these genes so that Igf2 is transcribed only from the paternal chromosome and H19 only from the maternal chromosome. There is growing evidence that this ‘Yin-Yang’ locus regulates embryonic development. Furthermore, recent evidence indicates that erasure of imprinting (hypomethylation of the Igf2-H19 locus on both chromosomes, which leads to downregulation of Igf2 and upregulation of H19 expression, plays an important role in regulating quiescence of pluripotent stem cells in adult organisms, and may be involved in the regulation of lifespan. In contrast, hypermethylation of this locus on both chromosomes (loss of imprinting results in Igf2 overexpression and is observed in several malignancies. In this review, we will discuss the biological consequences of changes in Igf2-H19 expression.

  11. Stemness-related markers in cancer

    Directory of Open Access Journals (Sweden)

    Wenxiu Zhao

    2017-01-01

    Full Text Available Cancer stem cells (CSCs, with their self-renewal ability and multilineage differentiation potential, are a critical subpopulation of tumor cells that can drive tumor initiation, growth, and resistance to therapy. Like embryonic and adult stem cells, CSCs express markers that are not expressed in normal somatic cells and are thus thought to contribute toward a “stemness” phenotype. This review summarizes the current knowledge of stemness-related markers in human cancers, with a particular focus on important transcription factors, protein surface markers, and signaling pathways.

  12. Placenta-an alternative source of stem cells

    International Nuclear Information System (INIS)

    Matikainen, Tiina; Laine, Jarmo

    2005-01-01

    The two most promising practical applications of human stem cells are cellular replacement therapies in human disease and toxicological screening of candidate drug molecules. Both require a source of human stem cells that can be isolated, purified, expanded in number and differentiated into the cell type of choice in a controlled manner. Currently, uses of both embryonic and adult stem cells are investigated. While embryonic stem cells are pluripotent and can differentiate into any specialised cell type, their use requires establishment of embryonic stem cell lines using the inner cell mass of an early pre-implantation embryo. As the blastocyst is destroyed during the process, ethical issues need to be carefully considered. The use of embryonic stem cells is also limited by the difficulties in growing large numbers of the cells without inducing spontaneous differentiation, and the problems in controlling directed differentiation of the cells. The use of adult stem cells, typically derived from bone marrow, but also from other tissues, is ethically non-controversial but their differentiation potential is more limited than that of the embryonic stem cells. Since human cord blood, umbilical cord, placenta and amnion are normally discarded at birth, they provide an easily accessible alternative source of stem cells. We review the potential and current status of the use of adult stem cells derived from the placenta or umbilical cord in therapeutic and toxicological applications

  13. Noninvasive near-infrared live imaging of human adult mesenchymal stem cells transplanted in a rodent model of Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Bossolasco P

    2012-01-01

    Full Text Available P Bossolasco1,*, L Cova2,*, G Levandis3, V Diana2, S Cerri3, G Lambertenghi Deliliers1, E Polli1, V Silani2,4, F Blandini3, MT Armentero31Fondazione Matarelli, Dipartimento di Farmacologia, Chemioterapia e Tossicologia Medica, Università degli Studi di Milano, Milan, 2Department of Neurology and Laboratory of Neuroscience-IRCCS Istituto Auxologico Italiano, Cusano Milanino, 3Laboratory of Functional Neurochemistry, Interdepartmental Research Centre for Parkinson’s Disease, IRCCS National Institute of Neurology “C Mondino”, Pavia, 4Department of Neurology and Laboratory of Neuroscience, Centro “Dino Ferrari” Università degli Studi di Milano-IRCCS Istituto Auxologico Italiano, Milan, Italy *These authors contributed equally to this workBackground: We have previously shown that human mesenchymal stem cells (hMSCs can reduce toxin-induced neurodegeneration in a well characterized rodent model of Parkinson’s disease. However, the precise mechanisms, optimal cell concentration required for neuroprotection, and detailed cell tracking need to be defined. We exploited a near-infrared imaging platform to perform noninvasive tracing following transplantation of tagged hMSCs in live parkinsonian rats.Methods: hMSCs were labeled both with a membrane intercalating dye, emitting in the near-infrared 815 nm spectrum, and the nuclear counterstain, Hoechst 33258. Effects of near-infrared dye on cell metabolism and proliferation were extensively evaluated in vitro. Tagged hMSCs were then administered to parkinsonian rats bearing a 6-hydroxydopamine-induced lesion of the nigrostriatal pathway, via two alternative routes, ie, intrastriatal or intranasal, and the cells were tracked in vivo and ex vivo using near-infrared technology.Results: In vitro, NIR815 staining was stable in long-term hMSC cultures and did not interfere with cell metabolism or proliferation. A significant near-infrared signal was detectable in vivo, confined around the injection

  14. Effects of Electroacupuncture Combined with Repetitive Transcranial Magnetic Stimulation on the Expression of Nestin in Neural Stem Cell after Focal Cerebral Ischemia in Adult Rats

    Institute of Scientific and Technical Information of China (English)

    HUANG Guofu; HUANG Xiaolin; CHEN Hong; HAY Xiaohua

    2009-01-01

    Objective: To investigate the influence of electroacupuncture (EA) combined with repetitive transeranial magnetic stimulation(rTMS) on the temporal profile of nestin expression after induction of focal cerebral isehemia in adult rats and to explore the mechanism of EA combined with rTMS in treating ischemic brain injury. Method: The model of transient focal ischemia was produced by occlusion of middle cerebral artery. Seventy-five Wistar rats were randomly divided into normal group, model group, EA group, rTMS group and EA +rTMS group. The neurologic impairment rating and ability of learning and memory were observed at the 7th、14th and 28th d after infarction respectively. Meanwhile, Western blotting was used to observe the number of nestin expression positive cells. Result: Nestin-positive cells were found in cortex, subgranular zone (SGZ), subventricular zone (SVZ) of the ipsilateral side at different time points after cerebral isehemia. The number of nestin-positive cells peaked at the 7th d, began to decrease at the 14th d and was significantly higher in EA+rTMS group than that in model group (P<0.05), then almost reached normal at the 28th d. The improvement of neural motor function deficits as well as the indexes of learning and memory were more obvious in EA+rTMS group compared with model group (P<0.01, P<0.05). These effects were most obvious in EA+rTMS group compared with the EA and rTMS group (P<0.05). Conclusion: EA and rTMS possess the potency of building up and can increase the number of nestin-positive cells in some brain regions after focal cerebral ischemia, which might be one of the important mechanisms of EA combined with rTMS in treating ischemia brain injury.

  15. Dental pulp stem cells differentiation reveals new insights in Oct4A dynamics.

    Directory of Open Access Journals (Sweden)

    Federico Ferro

    Full Text Available Although the role played by the core transcription factor network, which includes c-Myc, Klf4, Nanog, and Oct4, in the maintenance of embryonic stem cell (ES pluripotency and in the reprogramming of adult cells is well established, its persistence and function in adult stem cells are still debated. To verify its persistence and clarify the role played by these molecules in adult stem cell function, we investigated the expression pattern of embryonic and adult stem cell markers in undifferentiated and fully differentiated dental pulp stem cells (DPSC. A particular attention was devoted to the expression pattern and intracellular localization of the stemness-associated isoform A of Oct4 (Oct4A. Our data demonstrate that: Oct4, Nanog, Klf4 and c-Myc are expressed in adult stem cells and, with the exception of c-Myc, they are significantly down-regulated following differentiation. Cell differentiation was also associated with a significant reduction in the fraction of DPSC expressing the stem cell markers CD10, CD29 and CD117. Moreover, a nuclear to cytoplasm shuttling of Oct4A was identified in differentiated cells, which was associated with Oct4A phosphorylation. The present study would highlight the importance of the post-translational modifications in DPSC stemness maintenance, by which stem cells balance self-renewal versus differentiation. Understanding and controlling these mechanisms may be of great importance for stemness maintenance and stem cells clinical use, as well as for cancer research.

  16. Stepwise development of hematopoietic stem cells from embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Kenji Matsumoto

    Full Text Available The cellular ontogeny of hematopoietic stem cells (HSCs remains poorly understood because their isolation from and their identification in early developing small embryos are difficult. We attempted to dissect early developmental stages of HSCs using an in vitro mouse embryonic stem cell (ESC differentiation system combined with inducible HOXB4 expression. Here we report the identification of pre-HSCs and an embryonic type of HSCs (embryonic HSCs as intermediate cells between ESCs and HSCs. Both pre-HSCs and embryonic HSCs were isolated by their c-Kit(+CD41(+CD45(- phenotype. Pre-HSCs did not engraft in irradiated adult mice. After co-culture with OP9 stromal cells and conditional expression of HOXB4, pre-HSCs gave rise to embryonic HSCs capable of engraftment and long-term reconstitution in irradiated adult mice. Blast colony assays revealed that most hemangioblast activity was detected apart from the pre-HSC population, implying the early divergence of pre-HSCs from hemangioblasts. Gene expression profiling suggests that a particular set of transcripts closely associated with adult HSCs is involved in the transition of pre-HSC to embryonic HSCs. We propose an HSC developmental model in which pre-HSCs and embryonic HSCs sequentially give rise to adult types of HSCs in a stepwise manner.

  17. Stem cell treatment of degenerative eye disease

    Directory of Open Access Journals (Sweden)

    Ben Mead

    2015-05-01

    Full Text Available Stem cell therapies are being explored extensively as treatments for degenerative eye disease, either for replacing lost neurons, restoring neural circuits or, based on more recent evidence, as paracrine-mediated therapies in which stem cell-derived trophic factors protect compromised endogenous retinal neurons from death and induce the growth of new connections. Retinal progenitor phenotypes induced from embryonic stem cells/induced pluripotent stem cells (ESCs/iPSCs and endogenous retinal stem cells may replace lost photoreceptors and retinal pigment epithelial (RPE cells and restore vision in the diseased eye, whereas treatment of injured retinal ganglion cells (RGCs has so far been reliant on mesenchymal stem cells (MSC. Here, we review the properties of non-retinal-derived adult stem cells, in particular neural stem cells (NSCs, MSC derived from bone marrow (BMSC, adipose tissues (ADSC and dental pulp (DPSC, together with ESC/iPSC and discuss and compare their potential advantages as therapies designed to provide trophic support, repair and replacement of retinal neurons, RPE and glia in degenerative retinal diseases. We conclude that ESCs/iPSCs have the potential to replace lost retinal cells, whereas MSC may be a useful source of paracrine factors that protect RGC and stimulate regeneration of their axons in the optic nerve in degenerate eye disease. NSC may have potential as both a source of replacement cells and also as mediators of paracrine treatment.

  18. Stem cell treatment of degenerative eye disease.

    Science.gov (United States)

    Mead, Ben; Berry, Martin; Logan, Ann; Scott, Robert A H; Leadbeater, Wendy; Scheven, Ben A

    2015-05-01

    Stem cell therapies are being explored extensively as treatments for degenerative eye disease, either for replacing lost neurons, restoring neural circuits or, based on more recent evidence, as paracrine-mediated therapies in which stem cell-derived trophic factors protect compromised endogenous retinal neurons from death and induce the growth of new connections. Retinal progenitor phenotypes induced from embryonic stem cells/induced pluripotent stem cells (ESCs/iPSCs) and endogenous retinal stem cells may replace lost photoreceptors and retinal pigment epithelial (RPE) cells and restore vision in the diseased eye, whereas treatment of injured retinal ganglion cells (RGCs) has so far been reliant on mesenchymal stem cells (MSC). Here, we review the properties of non-retinal-derived adult stem cells, in particular neural stem cells (NSCs), MSC derived from bone marrow (BMSC), adipose tissues (ADSC) and dental pulp (DPSC), together with ESC/iPSC and discuss and compare their potential advantages as therapies designed to provide trophic support, repair and replacement of retinal neurons, RPE and glia in degenerative retinal diseases. We conclude that ESCs/iPSCs have the potential to replace lost retinal cells, whereas MSC may be a useful source of paracrine factors that protect RGC and stimulate regeneration of their axons in the optic nerve in degenerate eye disease. NSC may have potential as both a source of replacement cells and also as mediators of paracrine treatment. Copyright © 2015. Published by Elsevier B.V.

  19. Stem Cell-Based Therapies for Epidermolysis Bullosa

    Science.gov (United States)

    2015-12-01

    Methods , 2014. 11(3): p. 291-3. Differentiation of Human Induced Pluripotent Stem Cells into a Keratinocyte Lineage Igor Kogut...discovery of methods for reprogramming adult somatic cells into induced pluripotent stem cells (iPSCs) has raised the possibility of producing truly...2013. Generation of functional mul- tipotent keratinocytes from mouse induced pluripotent stem cells . Methods Mol Biol 961: 337–350.

  20. Early experiences mediate distinct adult gene expression and reproductive programs in Caenorhabditis elegans

    Science.gov (United States)

    Ow, Maria C.; Nichitean, Alexandra M.; Dorus, Steve; Hall, Sarah E.

    2018-01-01

    Environmental stress during early development in animals can have profound effects on adult phenotypes via programmed changes in gene expression. Using the nematode C. elegans, we demonstrated previously that adults retain a cellular memory of their developmental experience that is manifested by differences in gene expression and life history traits; however, the sophistication of this system in response to different environmental stresses, and how it dictates phenotypic plasticity in adults that contribute to increased fitness in response to distinct environmental challenges, was unknown. Using transcriptional profiling, we show here that C. elegans adults indeed retain distinct cellular memories of different environmental conditions. We identified approximately 500 genes in adults that entered dauer due to starvation that exhibit significant opposite (“seesaw”) transcriptional phenotypes compared to adults that entered dauer due to crowding, and are distinct from animals that bypassed dauer. Moreover, we show that two-thirds of the genes in the genome experience a 2-fold or greater seesaw trend in gene expression, and based upon the direction of change, are enriched in large, tightly linked regions on different chromosomes. Importantly, these transcriptional programs correspond to significant changes in brood size depending on the experienced stress. In addition, we demonstrate that while the observed seesaw gene expression changes occur in both somatic and germline tissue, only starvation-induced changes require a functional GLP-4 protein necessary for germline development, and both programs require the Argonaute CSR-1. Thus, our results suggest that signaling between the soma and the germ line can generate phenotypic plasticity as a result of early environmental experience, and likely contribute to increased fitness in adverse conditions and the evolution of the C. elegans genome. PMID:29447162

  1. Early experiences mediate distinct adult gene expression and reproductive programs in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Maria C Ow

    2018-02-01

    Full Text Available Environmental stress during early development in animals can have profound effects on adult phenotypes via programmed changes in gene expression. Using the nematode C. elegans, we demonstrated previously that adults retain a cellular memory of their developmental experience that is manifested by differences in gene expression and life history traits; however, the sophistication of this system in response to different environmental stresses, and how it dictates phenotypic plasticity in adults that contribute to increased fitness in response to distinct environmental challenges, was unknown. Using transcriptional profiling, we show here that C. elegans adults indeed retain distinct cellular memories of different environmental conditions. We identified approximately 500 genes in adults that entered dauer due to starvation that exhibit significant opposite ("seesaw" transcriptional phenotypes compared to adults that entered dauer due to crowding, and are distinct from animals that bypassed dauer. Moreover, we show that two-thirds of the genes in the genome experience a 2-fold or greater seesaw trend in gene expression, and based upon the direction of change, are enriched in large, tightly linked regions on different chromosomes. Importantly, these transcriptional programs correspond to significant changes in brood size depending on the experienced stress. In addition, we demonstrate that while the observed seesaw gene expression changes occur in both somatic and germline tissue, only starvation-induced changes require a functional GLP-4 protein necessary for germline development, and both programs require the Argonaute CSR-1. Thus, our results suggest that signaling between the soma and the germ line can generate phenotypic plasticity as a result of early environmental experience, and likely contribute to increased fitness in adverse conditions and the evolution of the C. elegans genome.

  2. Identification and isolation from either adult human bone marrow or G-CSF-mobilized peripheral blood of CD34(+)/CD133(+)/CXCR4(+)/ Lin(-)CD45(-) cells, featuring morphological, molecular, and phenotypic characteristics of very small embryonic-like (VSEL) stem cells.

    Science.gov (United States)

    Sovalat, Hanna; Scrofani, Maurice; Eidenschenk, Antoinette; Pasquet, Stéphanie; Rimelen, Valérie; Hénon, Philippe

    2011-04-01

    Recently, we demonstrated that normal human bone marrow (hBM)-derived CD34(+) cells, released into the peripheral blood after granulocyte colony-stimulating factor mobilization, contain cell subpopulations committed along endothelial and cardiac differentiation pathways. These subpopulations could play a key role in the regeneration of post-ischemic myocardial lesion after their direct intracardiac delivery. We hypothesized that these relevant cells might be issued from very small embryonic-like stem cells deposited in the BM during ontogenesis and reside lifelong in the adult BM, and that they could be mobilized into peripheral blood by granulocyte colony-stimulating factor. Samples of normal hBM and leukapheresis products harvested from cancer patients after granulocyte colony-stimulating factor mobilization were analyzed and sorted by multiparameter flow cytometry strategy. Immunofluorescence and reverse transcription quantitative polymerase chain reaction assays were performed to analyze the expression of typical pluripotent stem cells markers. A population of CD34(+)/CD133(+)/CXCR4(+)/Lin(-) CD45(-) immature cells was first isolated from the hBM or from leukapheresis products. Among this population, very small (2-5 μm) cells expressing Oct-4, Nanog, and stage-specific embryonic antigen-4 at protein and messenger RNA levels were identified. Our study supports the hypothesis that very small embryonic-like stem cells constitute a "mobile" pool of primitive/pluripotent stem cells that could be released from the BM into the peripheral blood under the influence of various physiological or pathological stimuli. In order to fully support that hBM- and leukapheresis product-derived very small embryonic-like stem cells are actually pluripotent, we are currently testing their ability to differentiate in vitro into cells from all three germ layers. Copyright © 2011 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  3. Stem cell self-renewal in intestinal crypt

    NARCIS (Netherlands)

    Simons, B.D.; Clevers, H.

    2011-01-01

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine

  4. Labeling and Imaging Mesenchymal Stem Cells with Quantum Dots

    Science.gov (United States)

    Mesenchymal stem cells (MSCs) are multipotent cells with the potential to differentiate into bone, cartilage, adipose and muscle cells. Adult derived MSCs are being actively investigated because of their potential to be utilized for therapeutic cell-based transplantation. Methods...

  5. Combination cell therapy with mesenchymal stem cells and neural stem cells for brain stroke in rats.

    Science.gov (United States)

    Hosseini, Seyed Mojtaba; Farahmandnia, Mohammad; Razi, Zahra; Delavari, Somayeh; Shakibajahromi, Benafsheh; Sarvestani, Fatemeh Sabet; Kazemi, Sepehr; Semsar, Maryam

    2015-05-01

    Brain stroke is the second most important events that lead to disability and morbidity these days. Although, stroke is important, there is no treatment for curing this problem. Nowadays, cell therapy has opened a new window for treating central nervous system disease. In some previous studies the Mesenchymal stem cells and neural stem cells. In this study, we have designed an experiment to assess the combination cell therapy (Mesenchymal and Neural stem cells) effects on brain stroke. The Mesenchymal stem cells were isolated from adult rat bone marrow and the neural stem cells were isolated from ganglion eminence of rat embryo 14 days. The Mesenchymal stem cells were injected 1 day after middle cerebral artery occlusion (MCAO) and the neural stem cells transplanted 7 day after MCAO. After 28 days, the neurological outcomes and brain lesion volumes were evaluated. Also, the activity of Caspase 3 was assessed in different groups. The group which received combination cell therapy had better neurological examination and less brain lesion. Also the combination cell therapy group had the least Caspase 3 activity among the groups. The combination cell therapy is more effective than Mesenchymal stem cell therapy and neural stem cell therapy separately in treating the brain stroke in rats.

  6. Stem cell self-renewal in intestinal crypt

    International Nuclear Information System (INIS)

    Simons, Benjamin D.; Clevers, Hans

    2011-01-01

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine and colon has remained the subject of debate. Recent studies based on targeted lineage tracing strategies, combined with the development of an organotypic culture system, have identified the crypt base columnar cell as the intestinal stem cell, and have unveiled the strategy by which the balance between proliferation and differentiation is maintained. These results show that intestinal stem cells operate in a dynamic environment in which frequent and stochastic stem cell loss is compensated by the proliferation of neighboring stem cells. We review the basis of these experimental findings and the insights they offer into the mechanisms of homeostatic stem cell regulation.

  7. Comparable results of autologous and allogeneic haematopoietic stem cell transplantation for adults with Philadelphia-positive acute lymphoblastic leukaemia in first complete molecular remission: An analysis by the Acute Leukemia Working Party of the EBMT.

    Science.gov (United States)

    Giebel, Sebastian; Labopin, Myriam; Potter, Michael; Poiré, Xavier; Sengeloev, Henrik; Socié, Gerard; Huynh, Anne; Afanasyev, Boris V; Schanz, Urs; Ringden, Olle; Kalhs, Peter; Beelen, Dietrich W; Campos, Antonio M; Masszi, Tamás; Canaani, Jonathan; Mohty, Mohamad; Nagler, Arnon

    2018-06-01

    Allogeneic haematopoietic stem cell transplantation (alloHSCT) is considered a standard treatment for patients with Philadelphia chromosome-positive acute lymphoblastic leukaemia (Ph+ ALL) achieving complete remission after induction containing tyrosine kinase inhibitors (TKIs). We retrospectively compared results of myeloablative alloHSCT from either matched sibling donor (MSD) or unrelated donor (URD) with autologous (auto) HSCT for adults with Ph+ ALL in molecular remission, treated between 2007 and 2014. In univariate analysis, the incidence of relapse at 2 years was 47% after autoHSCT, 28% after MSD-HSCT and 19% after URD-HSCT (P = 0.0002). Respective rates of non-relapse mortality were 2%, 18%, and 22% (P = 0.001). The probabilities of leukaemia-free survival were 52%, 55% and 60% (P = 0.69), while overall survival rates were 70%, 70% and 69% (P = 0.58), respectively. In multivariate analysis, there was a trend towards increased risk of overall mortality after MSD-HSCT (hazard ratio [HR], 1.5, P = 0.12) and URD-HSCT (HR, 1.6, P = 0.08) when referred to autoHSCT. The use of total body irradiation (TBI)-based regimens was associated with reduced risk of relapse (HR, 0.65, P = 0.02) and overall mortality (HR, 0.67, P = 0.01). In the era of TKIs, outcomes of myeloablative autoHSCT and alloHSCT for patients with Ph+ ALL in first molecular remission are comparable. Therefore, autoHSCT appears to be an attractive treatment option potentially allowing for circumvention of alloHSCT sequelae. Irrespective of the type of donor, TBI-based regimens should be considered the preferable type of conditioning for Ph+ ALL. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Age dependence of radiosensitivity of hemopoietic stem cells in rats

    International Nuclear Information System (INIS)

    Vacek, A.; Bartonickova, A.; Rotkovska, D.

    1982-01-01

    Within one week to 120 days of life the number of pluripotent hemopoietic stem cells in the femur increased 50-fold while in the spleen CFU dropped almost 6-fold. In adult mice hemopoiesis prevails in the bone marrow in early age, after birth it is significant in the spleen. The radioresistance of hemopoietic stem cells in adult mice is higher than in young. (M.D.)

  9. Mammary Stem Cells and Breast Cancer Stem Cells: Molecular Connections and Clinical Implications.

    Science.gov (United States)

    Celià-Terrassa, Toni

    2018-05-04

    Cancer arises from subpopulations of transformed cells with high tumor initiation and repopulation ability, known as cancer stem cells (CSCs), which share many similarities with their normal counterparts. In the mammary gland, several studies have shown common molecular regulators between adult mammary stem cells (MaSCs) and breast cancer stem cells (bCSCs). Cell plasticity and self-renewal are essential abilities for MaSCs to maintain tissue homeostasis and regenerate the gland after pregnancy. Intriguingly, these properties are similarly executed in breast cancer stem cells to drive tumor initiation, tumor heterogeneity and recurrence after chemotherapy. In addition, both stem cell phenotypes are strongly influenced by external signals from the microenvironment, immune cells and supportive specific niches. This review focuses on the intrinsic and extrinsic connections of MaSC and bCSCs with clinical implications for breast cancer progression and their possible therapeutic applications.

  10. Aging and stem cell therapy: AMPK as an applicable pharmacological target for rejuvenation of aged stem cells and achieving higher efficacy in stem cell therapy.

    Science.gov (United States)

    Khorraminejad-Shirazi, Mohammadhossein; Farahmandnia, Mohammad; Kardeh, Bahareh; Estedlal, Alireza; Kardeh, Sina; Monabati, Ahmad

    2017-10-19

    In recent years, tissue regeneration has become a promising field for developing stem cell-based transplantation therapies for human patients. Adult stem cells are affected by the same aging mechanisms that involve somatic cells. One of the mechanisms involved in cellular aging is hyperactivation of mechanistic target of rapamycin complex 1 (mTORC1) and disruption of 5' adenosine monophosphate-activated protein kinase (AMPK). Aging of stem cells results in their impaired regenerative capacity and depletion of stem cell pools in adult tissue, which results in lower efficacy of stem cell therapy. By utilizing an effective therapeutic intervention for aged stem cells, stem cell therapy can become more promising for future application. mTORC1 inhibition is a practical approach to preserve the stem cell pool. In this article, we review the dynamic interaction between sirtuin (silent mating type information regulation 2 homolog) 1, AMPK, and mTORC1. We propose that using AMPK activators such as 5-aminoimidazole-4-carboxamide ribonucleotide, A769662, metformin, and oxidized nicotinamide adenine dinucleotide (NAD + ) are practical ways to be employed for achieving better optimized results in stem cell-based transplantation therapies. Copyright © 2017 King Faisal Specialist Hospital & Research Centre. Published by Elsevier B.V. All rights reserved.

  11. Go with the Flow: Cerebrospinal Fluid Flow Regulates Neural Stem Cell Proliferation.

    Science.gov (United States)

    Kaneko, Naoko; Sawamoto, Kazunobu

    2018-06-01

    Adult neural stem cells in the wall of brain ventricles make direct contact with cerebrospinal fluid. In this issue of Cell Stem Cell, Petrik et al. (2018) demonstrate that these neural stem cells sense the flow of cerebrospinal fluid through a transmembrane sodium channel, ENaC, which regulates their proliferation. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Silent Waters Run Deep. Quiescent stem cells in homeostasis and cancer

    NARCIS (Netherlands)

    S.G. Roth (Sabrina)

    2012-01-01

    markdownabstract__Abstract__ The Introduction summarizes the current literature on quiescence in adult stem cell niches and the various methods for the isolation of quiescent stem cells, outlines the complexity of the intestinal stem cell niche, and formulates the hypothesis that quiescent

  13. Transgenerational epigenetic effects of the endocrine disruptor vinclozolin on pregnancies and female adult onset disease.

    Science.gov (United States)

    Nilsson, Eric E; Anway, Matthew D; Stanfield, Jacob; Skinner, Michael K

    2008-05-01

    Endocrine disruptor exposure during gonadal sex determination was previously found to induce male rat adult onset transgenerational disease (F1-F4 generation), and this was associated with an alteration in the epigenetic (i.e., DNA methylation) programming of the male germ line. The current study was designed to characterize the transgenerational disease phenotypes of the female adult offspring. Pregnant rats (F0 generation) were treated transiently with vinclozolin (i.e., fungicide with anti-androgenic activity) on embryonic (E) days E8-E14 of gestation. F1 control and vinclozolin generation offspring from different litters were mated to produce F2 offspring, and similarly F2 generation animals produced F3 generation offspring. Observations demonstrated that 9 out of 105 pregnant rats (8.6%) from the vinclozolin F1-F3 generations exhibited uterine hemorrhage and/or anemia late in pregnancy. None (0 out of 82) of the control F1-F3 generation females had similar pregnancy problems. Complete blood cell counts and serum chemistry profiles demonstrated that selected vinclozolin generation animals, but not controls, exhibited marked regenerative anemia in late pregnancy. Examination of kidney histology revealed moderate or severe glomerular abnormalities in 67% of the vinclozolin F2 and F3 generation adult females compared with 18% of the controls. Adult female vinclozolin generation animals also developed various types of tumors in 6.5% of the animals (11 out of 170), while 2% of control-line animals (3 out of 151) developed mammary tumors. Observations demonstrate that vinclozolin exposure during gonadal sex determination promotes a transgenerational increase in pregnancy abnormalities and female adult onset disease states.

  14. Hematopoietic stem cell origin of connective tissues.

    Science.gov (United States)

    Ogawa, Makio; Larue, Amanda C; Watson, Patricia M; Watson, Dennis K

    2010-07-01

    Connective tissue consists of "connective tissue proper," which is further divided into loose and dense (fibrous) connective tissues and "specialized connective tissues." Specialized connective tissues consist of blood, adipose tissue, cartilage, and bone. In both loose and dense connective tissues, the principal cellular element is fibroblasts. It has been generally believed that all cellular elements of connective tissue, including fibroblasts, adipocytes, chondrocytes, and bone cells, are generated solely by mesenchymal stem cells. Recently, a number of studies, including those from our laboratory based on transplantation of single hematopoietic stem cells, strongly suggested a hematopoietic stem cell origin of these adult mesenchymal tissues. This review summarizes the experimental evidence for this new paradigm and discusses its translational implications. Copyright 2010 ISEH - Society for Hematology and Stem Cells. All rights reserved.

  15. Stem cells in the human breast

    DEFF Research Database (Denmark)

    Petersen, Ole William; Polyak, Kornelia

    2010-01-01

    The origins of the epithelial cells participating in the development, tissue homeostasis, and cancer of the human breast are poorly understood. However, emerging evidence suggests a role for adult tissue-specific stem cells in these processes. In a hierarchical manner, these generate the two main...... mammary cell lineages, producing an increasing number of cells with distinct properties. Understanding the biological characteristics of human breast stem cells and their progeny is crucial in attempts to compare the features of normal stem cells and cancer precursor cells and distinguish these from...... nonprecursor cells and cells from the bulk of a tumor. A historical overview of research on human breast stem cells in primary tissue and in culture reveals the progress that has been made in this area, whereas a focus on the cell-of-origin and reprogramming that occurs during neoplastic conversion provides...

  16. Controling stem cell proliferation - CKIs at work

    NARCIS (Netherlands)

    Bruggeman, SWM; van Lohuizen, M

    2006-01-01

    The cyclin-dependent kinase inhibitors or CKIs are well recognized as intrinsic regulators of the cell cycle. Here, we discuss recent data implicating their activity in restraining adult stem cell self-renewal, and the role that proteins regulating CKI expression play in this process.

  17. Stem cell bioprocessing: fundamentals and principles.

    Science.gov (United States)

    Placzek, Mark R; Chung, I-Ming; Macedo, Hugo M; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Cha, Jae Min; Fauzi, Iliana; Kang, Yunyi; Yeo, David C L; Ma, Chi Yip Joan; Polak, Julia M; Panoskaltsis, Nicki; Mantalaris, Athanasios

    2009-03-06

    In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the 'omics' technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical-failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications.

  18. Stem cell applications in military medicine.

    Science.gov (United States)

    Christopherson, Gregory T; Nesti, Leon J

    2011-10-19

    There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers--and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research.

  19. Clonal analysis of stem cells in differentiation and disease.

    Science.gov (United States)

    Colom, Bartomeu; Jones, Philip H

    2016-12-01

    Tracking the fate of individual cells and their progeny by clonal analysis has redefined the concept of stem cells and their role in health and disease. The maintenance of cell turnover in adult tissues is achieved by the collective action of populations of stem cells with an equal likelihood of self-renewal or differentiation. Following injury stem cells exhibit striking plasticity, switching from homeostatic behavior in order to repair damaged tissues. The effects of disease states on stem cells are also being uncovered, with new insights into how somatic mutations trigger clonal expansion in early neoplasia. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  20. Promises and challenges of stem cell research for regenerative medicine.