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==2014==
==2014==
===Haematopoietic stem cell induction by somite-derived endothelial cells controlled by meox1===
Nature. 2014 Aug 21;512(7514):314-8. doi: 10.1038/nature13678. Epub 2014 Aug 13.
Nguyen PD1, Hollway GE2, Sonntag C3, Miles LB3, Hall TE3, Berger S3, Fernandez KJ4, Gurevich DB3, Cole NJ5, Alaei S6, Ramialison M3, Sutherland RL2, Polo JM6, Lieschke GJ3, Currie PD7.
Abstract
Haematopoietic stem cells (HSCs) are self-renewing stem cells capable of replenishing all blood lineages. In all vertebrate embryos that have been studied, definitive HSCs are generated initially within the dorsal aorta (DA) of the embryonic vasculature by a series of poorly understood inductive events. Previous studies have identified that signalling relayed from adjacent somites coordinates HSC induction, but the nature of this signal has remained elusive. Here we reveal that somite specification of HSCs occurs via the deployment of a specific endothelial precursor population, which arises within a sub-compartment of the zebrafish somite that we have defined as the endotome. Endothelial cells of the endotome are specified within the nascent somite by the activity of the homeobox gene meox1. Specified endotomal cells consequently migrate and colonize the DA, where they induce HSC formation through the deployment of chemokine signalling activated in these cells during endotome formation. Loss of meox1 activity expands the endotome at the expense of a second somitic cell type, the muscle precursors of the dermomyotomal equivalent in zebrafish, the external cell layer. The resulting increase in endotome-derived cells that migrate to colonize the DA generates a dramatic increase in chemokine-dependent HSC induction. This study reveals the molecular basis for a novel somite lineage restriction mechanism and defines a new paradigm in induction of definitive HSCs.
PMID 25119043


===Derivation of naive human embryonic stem cells===
===Derivation of naive human embryonic stem cells===

Revision as of 10:35, 23 August 2014

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Cite this page: Hill, M.A. (2024, March 28) Embryology Stem Cells. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Stem_Cells

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Note - This sub-heading shows an automated computer PubMed search using the listed sub-heading term. References appear in this list based upon the date of the actual page viewing. Therefore the list of references do not reflect any editorial selection of material based on content or relevance. In comparison, references listed on the content page and discussion page (under the publication year sub-headings) do include editorial selection based upon relevance and availability. (More? Pubmed Most Recent)


Stem Cell

<pubmed limit=5>Stem Cell</pubmed>

2014

Haematopoietic stem cell induction by somite-derived endothelial cells controlled by meox1

Nature. 2014 Aug 21;512(7514):314-8. doi: 10.1038/nature13678. Epub 2014 Aug 13.

Nguyen PD1, Hollway GE2, Sonntag C3, Miles LB3, Hall TE3, Berger S3, Fernandez KJ4, Gurevich DB3, Cole NJ5, Alaei S6, Ramialison M3, Sutherland RL2, Polo JM6, Lieschke GJ3, Currie PD7.

Abstract

Haematopoietic stem cells (HSCs) are self-renewing stem cells capable of replenishing all blood lineages. In all vertebrate embryos that have been studied, definitive HSCs are generated initially within the dorsal aorta (DA) of the embryonic vasculature by a series of poorly understood inductive events. Previous studies have identified that signalling relayed from adjacent somites coordinates HSC induction, but the nature of this signal has remained elusive. Here we reveal that somite specification of HSCs occurs via the deployment of a specific endothelial precursor population, which arises within a sub-compartment of the zebrafish somite that we have defined as the endotome. Endothelial cells of the endotome are specified within the nascent somite by the activity of the homeobox gene meox1. Specified endotomal cells consequently migrate and colonize the DA, where they induce HSC formation through the deployment of chemokine signalling activated in these cells during endotome formation. Loss of meox1 activity expands the endotome at the expense of a second somitic cell type, the muscle precursors of the dermomyotomal equivalent in zebrafish, the external cell layer. The resulting increase in endotome-derived cells that migrate to colonize the DA generates a dramatic increase in chemokine-dependent HSC induction. This study reveals the molecular basis for a novel somite lineage restriction mechanism and defines a new paradigm in induction of definitive HSCs.

PMID 25119043

Derivation of naive human embryonic stem cells

Proc Natl Acad Sci U S A. 2014 Mar 25;111(12):4484-9. doi: 10.1073/pnas.1319738111. Epub 2014 Mar 12.

Ware CB1, Nelson AM, Mecham B, Hesson J, Zhou W, Jonlin EC, Jimenez-Caliani AJ, Deng X, Cavanaugh C, Cook S, Tesar PJ, Okada J, Margaretha L, Sperber H, Choi M, Blau CA, Treuting PM, Hawkins RD, Cirulli V, Ruohola-Baker H.

Abstract

The naïve pluripotent state has been shown in mice to lead to broad and more robust developmental potential relative to primed mouse epiblast cells. The human naïve ES cell state has eluded derivation without the use of transgenes, and forced expression of OCT4, KLF4, and KLF2 allows maintenance of human cells in a naïve state [Hanna J, et al. (2010) Proc Natl Acad Sci USA 107(20):9222-9227]. We describe two routes to generate nontransgenic naïve human ES cells (hESCs). The first is by reverse toggling of preexisting primed hESC lines by preculture in the histone deacetylase inhibitors butyrate and suberoylanilide hydroxamic acid, followed by culture in MEK/ERK and GSK3 inhibitors (2i) with FGF2. The second route is by direct derivation from a human embryo in 2i with FGF2. We show that human naïve cells meet mouse criteria for the naïve state by growth characteristics, antibody labeling profile, gene expression, X-inactivation profile, mitochondrial morphology, microRNA profile and development in the context of teratomas. hESCs can exist in a naïve state without the need for transgenes. Direct derivation is an elusive, but attainable, process, leading to cells at the earliest stage of in vitro pluripotency described for humans. Reverse toggling of primed cells to naïve is efficient and reproducible.

PMID 24623855

2012

To identify early populations of committed progenitors derived from human embryonic stem cells (hESCs), we screened self-renewing, BMP4-treated and retinoic acid–treated cultures with >400 antibodies recognizing cell-surface antigens. Sorting of >30 subpopulations followed by transcriptional analysis of developmental genes identified four distinct candidate progenitor groups. Subsets detected in self-renewing cultures, including CXCR4+ cells, expressed primitive endoderm genes. Expression of Cxcr4 in primitive endoderm was confirmed in visceral endoderm of mouse embryos. BMP4-induced progenitors exhibited gene signatures of mesoderm, trophoblast and vascular endothelium, suggesting correspondence to gastrulation-stage primitive streak, chorion and allantois precursors, respectively. Functional studies in vitro and in vivo confirmed that ROR2+ cells produce mesoderm progeny, APA+ cells generate syncytiotrophoblasts and CD87+ cells give rise to vasculature. The same progenitor classes emerged during the differentiation of human induced pluripotent stem cells (hiPSCs). These markers and progenitors provide tools for purifying human tissue-regenerating progenitors and for studying the commitment of pluripotent stem cells to lineage progenitors.

Derivation of Xeno-Free and GMP-Grade Human Embryonic Stem Cells - Platforms for Future Clinical Applications

PLoS One. 2012;7(6):e35325. Epub 2012 Jun 20.

Tannenbaum SE, Tako Turetsky T, Singer O, Aizenman E, Kirshberg S, Ilouz N, Gil Y, Berman-Zaken Y, Perlman TS, Geva N, Levy O, Arbell D, Simon A, Ben-Meir A, Shufaro Y, Laufer N, Reubinoff BE. Source The Hadassah Human Embryonic Stem Cell Research Center, Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem, Israel.

Abstract

Clinically compliant human embryonic stem cells (hESCs) should be developed in adherence to ethical standards, without risk of contamination by adventitious agents. Here we developed for the first time animal-component free and good manufacturing practice (GMP)-compliant hESCs. After vendor and raw material qualification, we derived xeno-free, GMP-grade feeders from umbilical cord tissue, and utilized them within a novel, xeno-free hESC culture system. We derived and characterized three hESC lines in adherence to regulations for embryo procurement, and good tissue, manufacturing and laboratory practices. To minimize freezing and thawing, we continuously expanded the lines from initial outgrowths and samples were cryopreserved as early stocks and banks. Batch release criteria included DNA-fingerprinting and HLA-typing for identity, characterization of pluripotency-associated marker expression, proliferation, karyotyping and differentiation in-vitro and in-vivo. These hESCs may be valuable for regenerative therapy. The ethical, scientific and regulatory methodology presented here may serve for development of additional clinical-grade hESCs.

PMID 22745653

Stem Cell Meeting Program April 2012

Program

PubMed: Eiraku M | Truscott R | Jamieson R | Hinton D

2011

Efficient Culturing and Genetic Manipulation of Human Pluripotent Stem Cells

Human pluripotent stem cells (hPSC) hold great promise as models for understanding disease and as a source of cells for transplantation therapies. However, the lack of simple, robust and efficient culture methods remains a significant obstacle for realizing the utility of hPSCs. Here we describe a platform for the culture of hPSCs that 1) allows for dissociation and replating of single cells, 2) significantly increases viability and replating efficiency, 3) improves freeze/thaw viability 4) improves cloning efficiency and 5) colony size variation. When combined with standard methodologies for genetic manipulation, we found that the enhanced culture platform allowed for lentiviral transduction rates of up to 95% and electroporation efficiencies of up to 25%, with a significant increase in the total number of antibiotic-selected colonies for screening for homologous recombination. We further demonstrated the utility of the enhanced culture platform by successfully targeting the ISL1 locus. We conclude that many of the difficulties associated with culturing and genetic manipulation of hPSCs can be addressed with optimized culture conditions, and we suggest that the use of the enhanced culture platform could greatly improve the ease of handling and general utility of hPSCs.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0027495

2010

Spatial and temporal expression pattern of germ layer markers during human embryonic stem cell differentiation in embryoid bodies

Histochem Cell Biol. 2010 May;133(5):595-606. Epub 2010 Apr 6.

Pekkanen-Mattila M, Pelto-Huikko M, Kujala V, Suuronen R, Skottman H, Aalto-Setälä K, Kerkelä E. Source Regea Institute for Regenerative Medicine, University of Tampere, Tampere University Hospital, Biokatu 12, 33520, Tampere, Finland.

Abstract

Human embryonic stem cell (hESC) differentiation in embryoid bodies (EBs) provides a valuable tool to study the interplay of different germ layers and their influence on cell differentiation. The gene expression of the developing EBs has been shown in many studies, but the protein expression and the spatial composition of different germ layers in human EBs have not been systematically studied. The aim of the present work was to study the temporal and spatial organisation of germ layers based on the expression of mesoderm (Brachyury T), endoderm (AFP) and ectoderm (SOX1) markers during the early stages of differentiation in eight hESC lines. Tissue multi-array technology was applied to study the protein expression of a large number of EBs. According to our results, EB formation and the organisation of germ layers occurred in a similar manner in all the lines. During 12 days of differentiation, all the germ layer markers were present, but no obvious distinct trajectories were formed. However, older EBs were highly organised in structure. Pluripotency marker OCT3/4 expression persisted unexpectedly long in the differentiating EBs. Cavity formation was observed in the immunocytological sections, and caspase-3 expression was high, suggesting a role of apoptosis in hESC differentiation and/or EB formation. The expression of Brachyury T was notably low in all the lines, also those with the best cardiac differentiation capacity, while the expression of SOX1 was higher in some lines, suggesting that the neural differentiation propensity may be detectable already in the early stages of EB differentiation.

PMID 20369364

Real time imaging of human progenitor neurogenesis

PLoS One. 2010 Oct 7;5(10). pii: e13187. Keenan TM, Nelson AD, Grinager JR, Thelen JC, Svendsen CN.

Department of Neurology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America. Abstract

Human neural progenitors are increasingly being employed in drug screens and emerging cell therapies targeted towards neurological disorders where neurogenesis is thought to play a key role including developmental disorders, Alzheimer's disease, and depression. Key to the success of these applications is understanding the mechanisms by which neurons arise. Our understanding of development can provide some guidance but since little is known about the specifics of human neural development and the requirement that cultures be expanded in vitro prior to use, it is unclear whether neural progenitors obey the same developmental mechanisms that exist in vivo. In previous studies we have shown that progenitors derived from fetal cortex can be cultured for many weeks in vitro as undifferentiated neurospheres and then induced to undergo neurogenesis by removing mitogens and exposing them to supportive substrates. Here we use live time lapse imaging and immunocytochemical analysis to show that neural progenitors use developmental mechanisms to generate neurons. Cells with morphologies and marker profiles consistent with radial glia and recently described outer radial glia divide asymmetrically and symmetrically to generate multipolar intermediate progenitors, a portion of which express ASCL1. These multipolar intermediate progenitors subsequently divide symmetrically to produce CTIP2(+) neurons. This 3-cell neurogenic scheme echoes observations in rodents in vivo and in human fetal slice cultures in vitro, providing evidence that hNPCs represent a renewable and robust in vitro assay system to explore mechanisms of human neurogenesis without the continual need for fresh primary human fetal tissue. Knowledge provided by this and future explorations of human neural progenitor neurogenesis will help maximize the safety and efficacy of new stem cell therapies by providing an understanding of how to generate physiologically-relevant cell types that maintain their identities when placed in diagnostic or transplantation environments.

PMID: 20949053 http://www.ncbi.nlm.nih.gov/pubmed/20949053


http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0013187

2009

<pubmed>19570509</pubmed>"An emerging body of data suggests that pluripotent stem cells may be able to differentiate to form eggs and sperm. We discuss the state of the science and the potential social implications and offer recommendations for addressing some of the ethical and policy issues that would be raised by the availability of stem cell-derived gametes. ...PSC-derived gamete research represents the convergence of several areas of ethical and policy debate and inquiry 'stem cell research, human genetic research, reproductive technologies, and human enhancement' bringing many of today's most contentious ethical issues into the same conversation." (More? Epigenetics)

USA Stem Cells

  • USA Food and Drug Administration (FDA) 2008 public hearing on the safety of therapies that use human embryonic stem cells. "Cellular Therapies Derived from Human Embryonic Stem Cells "Considerations for Pre-Clinical Safety Testing and Patient Monitoring, April 10, 2008" The biotech company Geron plans to trial a stem cell based therapy for patients with acute spinal-cord injury. (More?FDA Meeting Briefing Document PDF)


Australian Stem Cells

File:Aus sen crest.gif

2006 A private members bill was introduced (19Oct06) and passed (7Nov06) in the Australian Senate amending an earlier act relating to stem cells research. Prohibition of Human Cloning for Reproduction and the Regulation of Human Embryo Research Amendment Act 2006 This will allow stem research using human embryos under strict controls and now requires passing through the House of Represenatives before the Amendment will become law. [../pdf/SenateStemCell06Bill19100603.pdf PDF - Amendment Bill 2006]

2005Lockhart Review "On 17 June 2005, the former Minister for Ageing, the Hon Julie Bishop MP, appointed a committee to conduct independent reviews of Australia's Prohibition of Human Cloning Act 2002 and the Research Involving Human Embryos Act 2002. The Committee was required to consult with the Australian, State and Territory governments and a broad range of people with expertise or experience in relevant disciplines. The Committee called for written submissions on the scope and operation of the two Acts." Lockhart Review | Lockhart Review - Media Release



Tlx3 neuronal differentiation from embryonic stem cells

<pubmed>18391221</pubmed> "The T cell leukemia 3 (Tlx3) gene has been implicated in specification of glutamatergic sensory neurons in the spinal cord. ...The sequential and coordinated expression of the proneural and neuronal subtype-specific genes identifies Tlx3 as a selector gene in ES cells undergoing neural differentiation."


Historic Findings 2006

Chen S, Do JT, Zhang Q, Yao S, Yan F, Peters EC, Scholer HR, Schultz PG, Ding S. Self-renewal of embryonic stem cells by a small molecule. Proc Natl Acad Sci U S A. 2006 Nov 14;103(46):17266-71.

"A previously uncharacterized heterocycle, SC1, was discovered that allows one to propagate murine ES cells in an undifferentiated, pluripotent state under chemically defined conditions in the absence of feeder cells, serum, and leukemia inhibitory factor."


File:Aus sen crest.gif Australian Legislation A private members bill put forward by Senator Kay PATTERSON was passed (06Dec06) by 20 votes in the House of Representatives amending an earlier "Prohibition of Human Cloning for Reproduction and the Regulation of Human Embryo Research Amendment Act 2006" relating to stem cells research. During the four day debate more than 100 MPs spoke on the bill and the majority were in favour of changing the law. The amendment will allow researchers to create and use embryos up to 14 days old for research. [../Notes/stemcell.htm Stem Cells] | ABC - Information on Threrapeutic Cloning | ABC - Researcher hails end of therapeutic cloning ban House of Representatives | Prohibition of Human Cloning for Reproduction and the Regulation of Human Embryo Research Amendment Bill 2006 |

File:Aus sen crest.gif Australian Legislation A private members bill was introduced (19Oct06) and passed (7Nov06) in the Australian Senate amending an earlier act relating to stem cells research. Prohibition of Human Cloning for Reproduction and the Regulation of Human Embryo Research Amendment Act 2006 This will allow stem research using human embryos under strict controls and now requires passing through the House of Represenatives before the Amendment will become law. [../pdf/SenateStemCell06Bill19100603.pdf PDF - Amendment Bill 2006]

Human embryonic stem cells and liver Baharvand H, Hashemi SM, Kazemi Ashtiani S, Farrokhi A. Differentiation of human embryonic stem cells into hepatocytes in 2D and 3D culture systems in vitro. Int J Dev Biol. 2006;50(7):645-52. "The differentiation of hESCs into hepatocyte-like cells within 3D collagen scaffolds containing exogenous growth factors, gives rise to cells displaying morphological features, gene expression patterns and metabolic activities characteristic of hepatocytes and may provide a source of differentiated cells for treatment of liver diseases."

File:Cellstemcell.jpg "Cell Press, is set to launch (July, 2007) a new monthly journal Cell Stem Cell published by Cell Press in affiliation with the International Society for Stem Cell Research (ISSCR) will include primary research, reviews, and commentaries while also serving as a forum for issues of stem cell research policy and ethics." Cell Stem Cell

Embryonic stem cells and not bone marrow cells can regenerate cardiac function Kolossov E, Bostani T, Roell W, Breitbach M, Pillekamp F, Nygren JM, Sasse P, Rubenchik O, Fries JW, Wenzel D, Geisen C, Xia Y, Lu Z, Duan Y, Kettenhofen R, Jovinge S, Bloch W, Bohlen H, Welz A, Hescheler J, Jacobsen SE, Fleischmann BK. Engraftment of engineered ES cell-derived cardiomyocytes but not BM cells restores contractile function to the infarcted myocardium. J Exp Med. 2006 Oct 2;203(10):2315-27. Epub 2006 Sep 5. "... Long-term engraftment (4-5 months) was observed when co-transplanting selected ES cell-derived cardiomyocytes and fibroblasts into the injured heart of syngeneic mice, and no teratoma formation was found (n = 60). Although transplantation of ES cell-derived cardiomyocytes improved heart function, BM cells had no positive effects. Furthermore, no contribution of BM cells to cardiac, endothelial, or smooth muscle neogenesis was detected."

25 years of Embryonic Stem Cells Nature WebFocus "This year marks the 25th anniversary of two papers reporting the first isolation of mouse ES cells."

Embryonic stem cells Suzuki A, Raya A, Kawakami Y, Morita M, Matsui T, Nakashima K, Gage FH, Rodriguez-Esteban C, Izpisua Belmonte JC. Nanog binds to Smad1 and blocks bone morphogenetic protein-induced differentiation of embryonic stem cells. Proc Natl Acad Sci U S A. 2006 Jun 26;

Neural Stem Cell Differentiation Ueno M, Matsumura M, Watanabe K, Nakamura T, Osakada F, Takahashi M, Kawasaki H, Kinoshita S, Sasai Y. Neural conversion of ES cells by an inductive activity on human amniotic membrane matrix. Proc Natl Acad Sci U S A. 2006 Jun 9 A recent study has shown the differentiation of embryonic stem cells into neural cells by contact with extracellular matrix components of the human amniotic membrane in serum-free medium. PNAS Link | [../Notes/neuron.htm Neural Notes]

Modifying Spermatogonial Stem Cells Kanatsu-Shinohara M, Ikawa M, Takehashi M, Ogonuki N, Miki H, Inoue K, Kazuki Y, Lee J, Toyokuni S, Oshimura M, Ogura A, Shinohara T. Production of knockout mice by random or targeted mutagenesis in spermatogonial stem cells. Proc Natl Acad Sci U S A. 2006 May 23;103(21):8018-23. "Here, we demonstrate successful gene trapping and homologous recombination in spermatogonial stem cells. ...These results demonstrate the feasibility of altering genes in tissue-specific stem cells in a manner similar to embryonic stem cells and have important implications for gene therapy and animal transgenesis."

(More? [#SSC Spermatogonial Stem Cell] See also commentary de Rooij DG. Rapid expansion of the spermatogonial stem cell tool box. Proc Natl Acad Sci U S A. 2006 May 23;103(21):7939-40.)


Earlier Links (2002 - 2004)

California Governor Schwarzenegger Endorses Stem-Cell Bonds Oct. 18, 2004 California Governor Arnold Schwarzenegger endorsed a proposal to sell $3 billion of bonds to fund stem-cell research, two weeks before a vote that may make California the biggest U.S. sponsor of such studies. The initiative is a response to President George W. Bush's decision to limit federal funding of research with embryonic stem cells, which are seen as a potential source of cures for disease. The governor's endorsement may benefit a campaign that only has a narrow lead among voters, according to a recent opinion poll. "Research that we do now holds the promise of cures for tomorrow," Schwarzenegger said in an e-mail statement to reporters. "California has always been a pioneer. We daringly led the way for the high-tech industry and now voters can help ensure we lead the way for the biotech industry." Read Bloomberg Article

Sydney Stem Cells "Embryonic stem cells created in Australian first"ABC News Thursday, June 24, 2004

The medical director of Sydney IVF, Robert Jansen, says while mainstream uses are still a few years away, the team's breakthrough will lead the way for new research. "They can be used by researchers for developing or learning more about how cells become other more specialised cells that might be used, for instance, to repopulate someone's pancreas if they have juvenile diabetes," he said.

May 2004 NIH Clinical Trials Launches Study of Hematopoietic Stem Cell Transplantation for Severe, Treatment-Resistant Lupus (NIAMS, May 13,2004)

A clinical therapeutic trial in the USA for hematopoietic stem cells in an autoimmune disease.

"A five-year study to see whether a therapy using transplantation of hematopoietic stem cells, blood stem cells found in bone marrow, can produce long-term remission for patients with severe, treatment-resistant systemic lupus erythematosus (or lupus), a rheumatic autoimmune disease that can affect the body's major organs. The study will include a basic research component to examine the roles of B and T cells, white blood cells in the immune system, in triggering lupus symptoms."

Read more of the NIH Press Release

Note that a May search of NIH Clinical Trials with "stem cell" found 302 study results.

Repeat search: NIH Clinical Trials with "stem cell"

As of 2002, there were available up to 60 human stem cell lines (according to information supplied to President Bush). ([#NIH(USA) More? NIH (USA) Stem Cell Information]) These cell lines exist in many different countries including: Australia, India, Israel, Sweden and USA. ([#lab list More? see list of Labs])

2001

Human Stem cells in the News

Mainly in regard to USA political position on Human Stem Cell Research (BBC links)

The external link to CNN requires Quicktime Stem Cell Animation

Original UNSW Embryology Pages

Stem Cells | Stem Cell Ethics | Cord Blood | Adult Stem Cells | Neural Stem Cells | Week 2 Stem Cells | Cloning