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Cite this page: Hill, M.A. (2019, December 12) Embryology Stem Cells. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Stem_Cells
Mehrotra P, Tseropoulos G, Bronner ME & Andreadis ST. (2019). Adult tissue-derived neural crest-like stem cells: Sources, regulatory networks, and translational potential: Concise review. Stem Cells Transl Med , , . PMID: 31738018 DOI.
Abstract Neural crest (NC) cells are a multipotent stem cell population that gives rise to a diverse array of cell types in the body, including peripheral neurons, Schwann cells (SC), craniofacial cartilage and bone, smooth muscle cells, and melanocytes. NC formation and differentiation into specific lineages takes place in response to a set of highly regulated signaling and transcriptional events within the neural plate border. Pre-migratory NC cells initially are contained within the dorsal neural tube from which they subsequently emigrate, migrating to often distant sites in the periphery. Following their migration and differentiation, some NC-like cells persist in adult tissues in a nascent multipotent state, making them potential candidates for autologous cell therapy. This review discusses the gene regulatory network responsible for NC development and maintenance of multipotency. We summarize the genes and signaling pathways that have been implicated in the differentiation of a post-migratory NC into mature myelinating SC. We elaborate on the signals and transcription factors involved in the acquisition of immature SC fate, axonal sorting of unmyelinated neuronal axons, and finally the path toward mature myelinating SC, which envelope axons within myelin sheaths, facilitating electrical signal propagation. The gene regulatory events guiding development of SC in-vivo provides insights into means for differentiating NC-like cells from adult human tissues into functional SC, which have the potential to provide autologous cell sources for the treatment of demyelinating and neurodegenerative disorders. © 2019 The Authors. STEM CELLS TRANSLATIONAL MEDICINE published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.
KEYWORDS: Schwann cells; demyelinating disorders; gene regulatory network; neural crest PMID: 31738018 DOI: 10.1002/sctm.19-0173
Generation of human oogonia from induced pluripotent stem cells in vitro
Yamashiro C, Sasaki K, Yabuta Y, Kojima Y, Nakamura T, Okamoto I, Yokobayashi S, Murase Y, Ishikura Y, Shirane K, Sasaki H, Yamamoto T & Saitou M. (2018). Generation of human oogonia from induced pluripotent stem cells in vitro. Science , , . PMID: 30237246 DOI.
Yamashiro C1,2, Sasaki K1,2, Yabuta Y1,2, Kojima Y1,2,3,4, Nakamura T1,2, Okamoto I1,2, Yokobayashi S1,2,4, Murase Y1,2, Ishikura Y1,2, Shirane K5,6, Sasaki H5,6, Yamamoto T3,4,7, Saitou M8,2,3,4. Author information Abstract Human in vitro gametogenesis may transform reproductive medicine. Human pluripotent stem cells (hPSCs) have been induced into primordial germ cell-like cells (hPGCLCs); however, further differentiation to a mature germ cell has not been achieved. Here, we show that hPGCLCs differentiate progressively into oogonia-like cells during a long-term in vitro culture (~four months) in xenogeneic reconstituted ovaries with mouse embryonic ovarian somatic cells. The hPGCLC-derived oogonia display hallmarks of epigenetic reprogramming, i.e., genome-wide DNA demethylation, imprint erasure, and extinguishment of aberrant DNA methylation in hPSCs, and acquire an immediate precursory state for meiotic recombination. Furthermore, the inactive X chromosome shows a progressive demethylation and reactivation, albeit partially. These findings establish the germline competence of hPSCs and provide a critical step toward human in vitro gametogenesis. PMID: 30237246 DOI: 10.1126/science.aat1674
Establishment and characterization of human theca stem cells and their differentiation into theca progenitor cells
Dalman A, Totonchi M & Valojerdi MR. (2018). Establishment and characterization of human theca stem cells and their differentiation into theca progenitor cells. J. Cell. Biochem. , , . PMID: 30132968 DOI.
Dalman A1, Totonchi M2, Valojerdi MR1,3. Author information Abstract In this study, we have characterized the human theca stem cells (hTSCs) and their differentiation into human theca progenitor cells (hTPCs). hTSCs were isolated from the theca layer of small antral follicles (3-5 mm in size). Alkaline phosphatase activity, cell cycle status, and cell surface markers were evaluated in hTSCs. The differentiation potential of these cells was investigated via differentiation of hTSCs into adipocyte-, osteocyte-, and chondrocyte-like cells. The cells also differentiated into hTPCs. The hTSCs were morphologically similar to human fibroblast cells (hFCs). Some of the cells were positive for alkaline phosphatase activity. The expression of OCT4 in hTSCs was significantly higher than that of human bone marrow mesenchymal stem cells (hBMSCs) and hFCs. To determine the type of OCT4 (isoform A or B), RT PCR was performed. The data showed that OCT-4A was expressed in hBMSCs and hTSCs but immunofluorescence analyses using the OCT-4A-specific and OCT4 antibodies did not show OCT-4A protein. In addition, cell cycle status showed that the number of hTSCs in the S phase was significantly higher than that of hFCs. CD29, CD44, CD73, CD90, and CD105 were present in hTSCs. Osteogenic, adipogenic, and chondrogenic differentiation was confirmed by cytochemical staining and lineage-specific transcripts. Our results showed that specific Dulbecco modified Eagle medium F12 culture medium results in the presence of hTPC markers. hTPCs displayed lipid droplets, appropriate gene expression, and secreted dehydroepiandrosterone and estradiol. hTSCs have the ability to differentiate into mesenchymal lineages and hTPCs. This study may provide a novel in vitro model for further investigation of theca cell maturation and differentiation. KEYWORDS: human mesenchymal stem cells; human theca progenitor cells (hTPCs); human theca stem cells (hTSCs) PMID: 30132968 DOI: 10.1002/jcb.27306
Isolation and characterization of mesenchymal stem cells from human fetus heart
PLoS One. 2018 Feb 8;13(2):e0192244. doi: 10.1371/journal.pone.0192244. eCollection 2018.
Garikipati VNS1, Singh SP1, Mohanram Y1, Gupta AK1, Kapoor D2, Nityanand S1.
Abstract BACKGROUND: Mesenchymal stem cells (MSCs) are promising cells for cardiovascular regenerative medicine. However, their potential may be limited, because of their restricted cardiovascular differentiation potential and decline in their number and functional characteristics with increasing donor age. We have previously shown that rat fetus heart harbors primitive MSCs and administration of these cells improved left ventricular (LV) function after ischemia/reperfusion injury in rats. To evaluate their potential as a new cell type for clinical cardiovascular cell therapy, we have undertaken this study on the isolation and characterization of human fetal cardiac MSCs (hfC-MSCs). METHODS: MSCs were isolated from the heart of five 14-16-week-old aborted human fetuses and studied for their growth characteristics, karyotypic stability and senescence over successive passages, expression of mesenchymal and embryonal markers by flow cytometry and immunocytochemistry, constitutive expression of cardiovascular genes by RT-PCR, differentiation into cells of the cardiovascular lineage and their immunomodulatory properties. RESULTS: The hfC-MSCs grew as adherent monolayer with spindle shaped morphology and exhibited rapid proliferation with an average population doubling time of 34 hours and expansion to up to more than 80 population doublings with maintenance of a normal karyotype and without senescence. Immunophenotyping showed that they had similar phenotype as human bone marrow mesenchymal stem cells (hBM-MSCs) expressing CD73, CD90, CD105 and lacking expression of CD31, CD34, CD45, HLA-DR. However, hfC-MSCs expressed significantly higher levels of CD117 and SSEA-4 compared to hBM-MSCs. In addition, hfC-MSCs expressed the embryonal markers Oct-4, Nanog and Sox-2 as compared to hBM-MSCs. Further, hfC-MSCs had significantly higher expression of the cardiovascular genes viz. ISL-1, flk-1, GATA-4, NKX2.5 and MDR-1 as compared to hBM-MSCs, and could be differentiated into major cardiovascular cells (cardiomyocytes, endothelial cells, smooth muscle cells). Interestingly, hfC-MSCs markedly reduced T-lymphocyte proliferation with an increased secretion of TGF-β and IL-10. CONCLUSIONS: Our results show that human fetus heart is a novel source of primitive MSCs with cardiovascular commitment which may have a potential therapeutic application in cardiovascular regenerative medicine.
PMID: 29420637 DOI: 10.1371/journal.pone.0192244
Distinct SoxB1 networks are required for naïve and primed pluripotency
Elife. 2017 Dec 19;6. pii: e27746. doi: 10.7554/eLife.27746.
Corsinotti A1,2, Wong FC1, Tatar T1, Szczerbinska I1, Halbritter F1, Colby D1, Gogolok S1, Pantier R1, Liggat K1, Mirfazeli ES1, Hall-Ponsele E1, Mullin NP1, Wilson V1, Chambers I1.
Deletion of Sox2 from mouse embryonic stem cells (ESCs) causes trophectodermal differentiation. While this can be prevented by enforced expression of the related SOXB1 proteins, SOX1 or SOX3, the roles of SOXB1 proteins in epiblast stem cell (EpiSC) pluripotency are unknown. Here, we show that Sox2 can be deleted from EpiSCs with impunity. This is due to a shift in the balance of SoxB1 expression in EpiSCs, which have decreased Sox2 and increased Sox3 compared to ESCs. Consistent with functional redundancy, Sox3 can also be deleted from EpiSCs without eliminating self-renewal. However, deletion of both Sox2 and Sox3 prevents self-renewal. The overall SOXB1 levels in ESCs affect differentiation choices: neural differentiation of Sox2 heterozygous ESCs is compromised, while increased SOXB1 levels divert the ESC to EpiSC transition towards neural differentiation. Therefore, optimal SOXB1 levels are critical for each pluripotent state and for cell fate decisions during exit from naïve pluripotency. KEYWORDS: Embryonic stem cells; Epiblast stem cells; Pluripotency; Sox; developmental biology; mouse; stem cells; transcription factors PMID: 29256862 PMCID: PMC5758114 DOI: 10.7554/eLife.27746
Long-term glycemic control using polymer-encapsulated human stem cell-derived beta cells in immune-competent mice
Nat Med. 2016 Mar;22(3):306-11. doi: 10.1038/nm.4030. Epub 2016 Jan 25.
Vegas AJ1,2, Veiseh O1,2,3, Gürtler M4, Millman JR4, Pagliuca FW4, Bader AR1,2, Doloff JC1,2, Li J1,2, Chen M1,2, Olejnik K1,2, Tam HH1,2,3, Jhunjhunwala S1,2, Langan E1,2, Aresta-Dasilva S1,2, Gandham S1,2, McGarrigle JJ5, Bochenek MA5, Hollister-Lock J6, Oberholzer J5, Greiner DL7, Weir GC6, Melton DA4,8, Langer R1,2,3,9,10, Anderson DG1,2,3,9,10.
The transplantation of glucose-responsive, insulin-producing cells offers the potential for restoring glycemic control in individuals with diabetes. Pancreas transplantation and the infusion of cadaveric islets are currently implemented clinically, but these approaches are limited by the adverse effects of immunosuppressive therapy over the lifetime of the recipient and the limited supply of donor tissue. The latter concern may be addressed by recently described glucose-responsive mature beta cells that are derived from human embryonic stem cells (referred to as SC-β cells), which may represent an unlimited source of human cells for pancreas replacement therapy. Strategies to address the immunosuppression concerns include immunoisolation of insulin-producing cells with porous biomaterials that function as an immune barrier. However, clinical implementation has been challenging because of host immune responses to the implant materials. Here we report the first long-term glycemic correction of a diabetic, immunocompetent animal model using human SC-β cells. SC-β cells were encapsulated with alginate derivatives capable of mitigating foreign-body responses in vivo and implanted into the intraperitoneal space of C57BL/6J mice treated with streptozotocin, which is an animal model for chemically induced type 1 diabetes. These implants induced glycemic correction without any immunosuppression until their removal at 174 d after implantation. Human C-peptide concentrations and in vivo glucose responsiveness demonstrated therapeutically relevant glycemic control. Implants retrieved after 174 d contained viable insulin-producing cells.
Pluripotent stem cells progressing to the clinic
Nat Rev Mol Cell Biol. 2016 Feb 23;17(3):194-200. doi: 10.1038/nrm.2016.10.
Trounson A1, DeWitt ND2,3.
Basic experimental stem cell research has opened up the possibility of many diverse clinical applications; however, translation to clinical trials has been restricted to only a few diseases. To broaden this clinical scope, pluripotent stem cell derivatives provide a uniquely scalable source of functional differentiated cells that can potentially repair damaged or diseased tissues to treat a wide spectrum of diseases and injuries. However, gathering sound data on their distribution, longevity, function and mechanisms of action in host tissues is imperative to realizing their clinical benefit. The large-scale availability of treatments involving pluripotent stem cells remains some years away, because of the long and demanding regulatory pathway that is needed to ensure their safety. PMID 26908143
Pluripotency, Differentiation, and Reprogramming: A Gene Expression Dynamics Model with Epigenetic Feedback Regulation
PLoS Comput Biol. 2015 Aug 26;11(8):e1004476. doi: 10.1371/journal.pcbi.1004476. eCollection 2015.
Miyamoto T1, Furusawa C2, Kaneko K1.
Embryonic stem cells exhibit pluripotency: they can differentiate into all types of somatic cells. Pluripotent genes such as Oct4 and Nanog are activated in the pluripotent state, and their expression decreases during cell differentiation. Inversely, expression of differentiation genes such as Gata6 and Gata4 is promoted during differentiation. The gene regulatory network controlling the expression of these genes has been described, and slower-scale epigenetic modifications have been uncovered. Although the differentiation of pluripotent stem cells is normally irreversible, reprogramming of cells can be experimentally manipulated to regain pluripotency via overexpression of certain genes. Despite these experimental advances, the dynamics and mechanisms of differentiation and reprogramming are not yet fully understood. Based on recent experimental findings, we constructed a simple gene regulatory network including pluripotent and differentiation genes, and we demonstrated the existence of pluripotent and differentiated states from the resultant dynamical-systems model. Two differentiation mechanisms, interaction-induced switching from an expression oscillatory state and noise-assisted transition between bistable stationary states, were tested in the model. The former was found to be relevant to the differentiation process. We also introduced variables representing epigenetic modifications, which controlled the threshold for gene expression. By assuming positive feedback between expression levels and the epigenetic variables, we observed differentiation in expression dynamics. Additionally, with numerical reprogramming experiments for differentiated cells, we showed that pluripotency was recovered in cells by imposing overexpression of two pluripotent genes and external factors to control expression of differentiation genes. Interestingly, these factors were consistent with the four Yamanaka factors, Oct4, Sox2, Klf4, and Myc, which were necessary for the establishment of induced pluripotent stem cells. These results, based on a gene regulatory network and expression dynamics, contribute to our wider understanding of pluripotency, differentiation, and reprogramming of cells, and they provide a fresh viewpoint on robustness and control during development. PMID 26308610
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.
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.
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.
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.
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.
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.
Stem Cell Meeting Program April 2012
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.
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.
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.
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
<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
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])
Human Stem cells in the News
Mainly in regard to USA political position on Human Stem Cell Research (BBC links)
- Bush stem cell move widely (10 August)
- Press see 'political' stem cell decision (10 August)
- Bush facing stem cell storm (10 August)
- Stem cell compromise angers hardliners (10 August)
- Stem cells: Q & A (10 August)
- Japan set to embrace stem cell research (1 August)
- Read this May 2000 article on Stem Cells from NIH USA
The external link to CNN requires Quicktime Stem Cell Animation