Zap70 functions to maintain stemness of mouse embryonic stem cells by negatively regulating Jak1/Stat3/c-Myc signaling

PubMed Central

Cha, Young; Moon, Bo-Hyun; Lee, Mi-Ok; Ahn, Hee-Jin; Lee, Hye-Jin; Lee, Kyung-Ah; Fornace, Albert J.; Kim, Kwang-Soo; Cha, Hyuk-Jin; Park, Kyung-Soon

2011-01-01

Zeta-chain associated protein kinase-70 (Zap70), a Syk family tyrosine kinase, has been reported to be present exclusively in normal T cells, Natural Killer (NK) cells, and B cells, serving as a pivotal regulator of antigen-mediated receptor signaling and development. In this study, we report that Zap70 is expressed in undifferentiated mouse embryonic stem cells (mESCs) and may critically regulate self-renewal and pluripotency in mESCs. We found that Zap70 knocked-down mESCs (Zap70KD) show sustained self-renewal and defective differentiation. In addition, we present evidence that the sustained self-renewal in Zap70KD is associated with enhanced Jak/Stat3 signaling and c-Myc induction. These altered signaling appears to result from up-regulated LIFR and down-regulated SHP-1 phosphatase activity. Based on these results, we propose that, in undifferentiated mESCs, Zap70 plays important roles in modulating the balance between self-renewal capacity and pluripotent differentiation ability as a key regulator of the Jak/Stat3/c-Myc signaling pathway. PMID:20641039

Inefficient reprogramming of the hematopoietic stem cell genome following nuclear transfer.

PubMed

Inoue, Kimiko; Ogonuki, Narumi; Miki, Hiromi; Hirose, Michiko; Noda, Shinichi; Kim, Jin-Moon; Aoki, Fugaku; Miyoshi, Hiroyuki; Ogura, Atsuo

2006-05-15

In general, cloning undifferentiated preimplantation embryos (blastomeres) or embryonic stem cells is more efficient than cloning differentiated somatic cells. Therefore, there has been an assumption that tissue-specific stem cells might serve as efficient donors for nuclear transfer because of the undifferentiated state of their genome. Here, we show that this is not the case with adult hematopoietic stem cells (HSCs). Although we have demonstrated for the first time that mouse HSCs can be cloned to generate offspring, the birth rates (0-0.7%) were lowest among the clones tested (cumulus, immature Sertoli and fibroblast cells). Only 6% of reconstructed embryos reached the morula or blastocyst stage in vitro (versus 46% for cumulus clones; P < 5 x 10(-10)). Transcription and gene expression analyses of HSC clone embryos revealed that they initiated zygotic gene activation (ZGA) at the appropriate timing, but failed to activate five out of six important embryonic genes examined, including Hdac1 (encoding histone deacetylase 1), a key regulator of subsequent ZGA. These results suggest that the HSC genome has less plasticity than we imagined, at least in terms of reprogrammability in the ooplasm after nuclear transfer.

Undifferentiated murine embryonic stem cells used to model the effects of the blue-green algal toxin cylindrospermopsin on preimplantation embryonic cell proliferation.

PubMed

Reid, Katherine J; Lang, Kenneth; Froscio, Suzanne; Humpage, Andrew J; Young, Fiona M

2015-11-01

Undifferentiated mouse embryonic stem cell (mES) proliferation in vitro resembles aspects of in vivo pre-implantation embryonic development. mES were used to assess the embryo-toxicity of cylindrospermopsin (CYN), a water contaminant with an Australian Drinking Water Guideline (ADWG) of 1 μg/L. mES exposed to 0-1 μg/mL CYN for 24-168 h were subjected to an optimised crystal violet viability assay. mES exposed to retinoic acid ± 1 μg/L CYN differentiated into neural-like cells confirmed by morphological examination and RT-PCR for Oct4, Brachyury and Nestin. The CYN No Observed Effect Concentration (OEC) was 0.5 μg/mL, the Lowest OEC was 1 μg/mL (p < 0.001, n = 3), and the IC50 was 0.86 μg/mL after 24 h. The ADWG 1 μg/L CYN did not affect differentiation or proliferation after 72 h, but decreased proliferation after 168 h (p < 0.05). We conclude that higher algal bloom-associated CYN concentrations have the potential to impair in vivo pre-implantation development, and the mES crystal violet assay has broad application to screening environmental toxins. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nanofibrous substrates support colony formation and maintain stemness of human embryonic stem cells

PubMed Central

Gauthaman, Kalamegam; Venugopal, Jayarama Reddy; Yee, Fong Chui; Peh, Gary Swee Lim; Ramakrishna, Seeram; Bongso, Ariff

2009-01-01

Inadequate cell numbers in culture is one of the hurdles currently delaying the application of human embryonic stem cells (hESCs) for transplantation therapy. Nanofibrous scaffolds have been effectively used to expand and differentiate non-colony forming multipotent mesenchymal stem cells (MSC) for the repair of tissues or organs. In the present study, we evaluated the influence of nanofibrous scaffolds for hESC proliferation, increase in colony formation, self-renewal properties, undifferentiation and retention of ‘stemness’. Polycaprolactone/collagen (PCL/collagen) and PCL/gelatin nanofibrous scaffolds were fabricated using electrospinning technology. The hESCs were seeded on the nanofibrous scaffolds in the presence or absence of mitomycin-C treated mouse embryonic fibroblasts (MEFs). The hESCs grown on both scaffolds in the presence of the MEFs produced an increase in cell growth of 47.58% (P≤ 0.006) and 40.18% (P≤ 0.005), respectively, over conventional controls of hESCs on MEFs alone. The hESC colonies were also larger in diameter on the scaffolds compared to controls (PCL/collagen, 156.25 ± 7 μM and PCL/gelatin, 135.42 ± 5 μM). Immunohistochemistry of the hESCs grown on the nanofibrous scaffolds with MEFs, demonstrated positive staining for the various stemness-related markers (octamer 4 [OCT-4], tumour rejection antigen-1–60, GCTM-2 and TG-30), and semi-quantitative RT-PCR for the pluripotent stemness genomic markers (NANOG, SOX-2, OCT-4) showed that they were also highly expressed. Continued successful propagation of hESC colonies from nanofibrous scaffolds back to conventional culture on MEFs was also possible. Nanofibrous scaffolds support hESC expansion in an undifferentiated state with retention of stemness characteristics thus having tremendous potential in scaling up cell numbers for transplantation therapy. PMID:19228268

Identification of integrin heterodimers functioning on the surface of undifferentiated porcine primed embryonic stem cells.

PubMed

Kim, Hwa-Young; Baek, Song; Han, Na Rae; Lee, Eunsong; Park, Choon-Keun; Lee, Seung Tae

2018-05-29

In vitro expansion of undifferentiated porcine primed embryonic stem (ES) cells is facilitated by use of non-cellular niches that mimic three-dimensional (3D) microenvironments enclosing an inner cell mass of porcine blastocysts. Therefore, we investigated the integrin heterodimers on the surface of undifferentiated porcine primed ES cells for the purpose of developing a non-cellular niche to support in vitro maintenance of the self-renewal ability of porcine primed ES cells. Immunocytochemistry and a fluorescence immunoassay were performed to assess integrin α and β subunit levels, and attachment and antibody inhibition assays were used to evaluate the function of integrin heterodimers. The integrin α 3 , α 5 , α 6 , α 9 , α V , and β 1 subunits, but not the α 1 , α 2 , α 4 , α 7 , and α 8 subunits, were identified on the surface of undifferentiated porcine primed ES cells. Subsequently, significant increase of their adhesion to fibronectin, tenascin C and vitronectin were observed and functional blocking of integrin heterodimer α 5 β 1 , α 9 β 1 , or α V β 1 showed significantly inhibited adhesion to fibronectin, tenascin C, or vitronectin. No integrin α 6 β 1 heterodimer?mediated adhesion to laminin was detected. These results demonstrate that active α 5 β 1 , α 9 β 1 , and α V β 1 integrin heterodimers are present on the surface of undifferentiated porcine primed ES cells, together with inactive integrin α 3 (presumed) and α 6 subunits. This article is protected by copyright. All rights reserved.

Modulation of Differentiation Processes in Murine Embryonic Stem Cells Exposed to Parabolic Flight-Induced Acute Hypergravity and Microgravity.

PubMed

Acharya, Aviseka; Brungs, Sonja; Henry, Margit; Rotshteyn, Tamara; Singh Yaduvanshi, Nirmala; Wegener, Lucia; Jentzsch, Simon; Hescheler, Jürgen; Hemmersbach, Ruth; Boeuf, Helene; Sachinidis, Agapios

2018-06-15

Embryonic developmental studies under microgravity conditions in space are very limited. To study the effects of short-term altered gravity on embryonic development processes, we exposed mouse embryonic stem cells (mESCs) to phases of hypergravity and microgravity and studied the differentiation potential of the cells using wide-genome microarray analysis. During the 64th European Space Agency's parabolic flight campaign, mESCs were exposed to 31 parabolas. Each parabola comprised phases lasting 22 s of hypergravity, microgravity, and a repeat of hypergravity. On different parabolas, RNA was isolated for microarray analysis. After exposure to 31 parabolas, mESCs (P31 mESCs) were further differentiated under normal gravity (1 g) conditions for 12 days, producing P31 12-day embryoid bodies (EBs). After analysis of the microarrays, the differentially expressed genes were analyzed using different bioinformatic tools to identify developmental and nondevelopmental biological processes affected by conditions on the parabolic flight experiment. Our results demonstrated that several genes belonging to GOs associated with cell cycle and proliferation were downregulated in undifferentiated mESCs exposed to gravity changes. However, several genes belonging to developmental processes, such as vasculature development, kidney development, skin development, and to the TGF-β signaling pathway, were upregulated. Interestingly, similar enriched and suppressed GOs were obtained in P31 12-day EBs compared with ground control 12-day EBs. Our results show that undifferentiated mESCs exposed to alternate hypergravity and microgravity phases expressed several genes associated with developmental/differentiation and cell cycle processes, suggesting a transition from the undifferentiated pluripotent to a more differentiated stage of mESCs.

[Breakthrough in research on pluripotent stem cells and their application in medicine].

PubMed

Valdimarsdóttir, Guðrún; Richter, Anne

2015-12-01

Embryonic stem cells are, as the name indicates, isolated from embryos. They are pluripotent cells which can be maintained undifferentiated or induced to differentiate into any cell type of the body. In 1998 the first isolation of human embryonic stem cells was successful and they became an interesting source for stem cell regenerative medicine. Only 8 years later pluripotent stem cells were generated by reprogramming somatic cells into induced pluripotent stem cells (iPSCs). This was a revolution in the way people thought of cell commitment during development. Since then, a lot of research has been done in understanding the molecular biology of pluripotent stem cells. iPSCs can be generated from somatic cells of a patient and therefore have the same genome. Hence, iPSCs have great potential application in medicine, as they can be utilized in disease modelling, drug screening and cell replacement therapy.

Pluripotency of adult stem cells derived from human and rat pancreas

NASA Astrophysics Data System (ADS)

Kruse, C.; Birth, M.; Rohwedel, J.; Assmuth, K.; Goepel, A.; Wedel, T.

Adult stem cells are undifferentiated cells found within fully developed tissues or organs of an adult individuum. Until recently, these cells have been considered to bear less self-renewal ability and differentiation potency compared to embryonic stem cells. In recent studies an undifferentiated cell type was found in primary cultures of isolated acini from exocrine pancreas termed pancreatic stellate cells. Here we show that pancreatic stellate-like cells have the capacity of extended self-renewal and are able to differentiate spontaneously into cell types of all three germ layers expressing markers for smooth muscle cells, neurons, glial cells, epithelial cells, chondrocytes and secretory cells (insulin, amylase). Differentiation and subsequent formation of three-dimensional cellular aggregates (organoid bodies) were induced by merely culturing pancreatic stellate-like cells in hanging drops. These cells were developed into stable, long-term, in vitro cultures of both primary undifferentiated cell lines as well as organoid cultures. Thus, evidence is given that cell lineages of endodermal, mesodermal, and ectodermal origin arise spontaneously from a single adult undifferentiated cell type. Based on the present findings it is assumed that pancreatic stellate-like cells are a new class of lineage uncommitted pluripotent adult stem cells with a remarkable self-renewal ability and differentiation potency. The data emphasize the versatility of adult stem cells and may lead to a reappraisal of their use for the treatment of inherited disorders or acquired degenerative diseases.

Sialyl-lactotetra, a novel cell surface marker of undifferentiated human pluripotent stem cells.

PubMed

Barone, Angela; Säljö, Karin; Benktander, John; Blomqvist, Maria; Månsson, Jan-Eric; Johansson, Bengt R; Mölne, Johan; Aspegren, Anders; Björquist, Petter; Breimer, Michael E; Teneberg, Susann

2014-07-04

Cell surface glycoconjugates are used as markers for undifferentiated pluripotent stem cells. Here, antibody binding and mass spectrometry characterization of acid glycosphingolipids isolated from a large number (1 × 10(9) cells) of human embryonic stem cell (hESC) lines allowed identification of several novel acid glycosphingolipids, like the gangliosides sialyl-lactotetraosylceramide and sialyl-globotetraosylceramide, and the sulfated glycosphingolipids sulfatide, sulf-lactosylceramide, and sulf-globopentaosylceramide. A high cell surface expression of sialyl-lactotetra on hESC and human induced pluripotent stem cells (hiPSC) was demonstrated by flow cytometry, immunohistochemistry, and electron microscopy, whereas sulfated glycosphingolipids were only found in intracellular compartments. Immunohistochemistry showed distinct cell surface anti-sialyl-lactotetra staining on all seven hESC lines and three hiPSC lines analyzed, whereas no staining of hESC-derived hepatocyte-like or cardiomyocyte-like cells was obtained. Upon differentiation of hiPSC into hepatocyte-like cells, the sialyl-lactotetra epitope was rapidly down-regulated and not detectable after 14 days. These findings identify sialyl-lactotetra as a promising marker of undifferentiated human pluripotent stem cells. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

[Expression of embryonic markers in pterygium derived mesenchymal cells].

PubMed

Pascual, G; Montes, M A; Pérez-Rico, C; Pérez-Kohler, B; Bellón, J M; Buján, J

2010-12-01

Destruction of the limbal epithelium barrier is the most important mechanism of pterygium formation (conjunctiva proliferation, encroaching onto the cornea). It is thought to arise from activated and proliferating limbal epithelial stem cells. The objective of this study is to evaluate the presence of undifferentiated mesenchymal cells (stem cells) in cultured cells extracted from human pterygium. Cells from 6 human pterygium were isolated by explantation and placed in cultures with amniomax medium. Once the monolayer was reached the cells were seeded onto 24 well microplates. The cells were studied in the second sub-culture. The immunohistochemical expression of different embryonic stem cell markers, OCT3/4 and CD9, was analysed. The differentiated phenotypes were characterised with the monoclonal antibodies anti-CD31, α-actin and vimentin. All the cell populations obtained from pterygium showed vimentin expression. Less than 1% of the cells were positive for CD31 and α-actin markers. The majority of the cell population was positive for OCT3/4 and CD9. The cell population obtained from pterygium expressed mesenchymal cell phenotype and embryonic markers, such us OCT3/4 and CD9. This undifferentiated population could be involved in the large recurrence rate of this type of tissue after surgery. Copyright © 2010 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

Large-scale production of embryonic red blood cells from human embryonic stem cells.

PubMed

Olivier, Emmanuel N; Qiu, Caihong; Velho, Michelle; Hirsch, Rhoda Elison; Bouhassira, Eric E

2006-12-01

To develop a method to produce in culture large number of erythroid cells from human embryonic stem cells. Human H1 embryonic stem cells were differentiated into hematopoietic cells by coculture with a human fetal liver cell line, and the resulting CD34-positive cells were expanded in vitro in liquid culture using a three-step method. The erythroid cells produced were then analyzed by light microscopy and flow cytometry. Globin expression was characterized by quantitative reverse-transcriptase polymerase chain reaction and by high-performance liquid chromatography. CD34-positive cells produced from human embryonic stem cells could be efficiently differentiated into erythroid cells in liquid culture leading to a more than 5000-fold increase in cell number. The erythroid cells produced are similar to primitive erythroid cells present in the yolk sac of early human embryos and did not enucleate. They are fully hemoglobinized and express a mixture of embryonic and fetal globins but no beta-globin. We have developed an experimental protocol to produce large numbers of primitive erythroid cells starting from undifferentiated human embryonic stem cells. As the earliest human erythroid cells, the nucleated primitive erythroblasts, are not very well characterized because experimental material at this stage of development is very difficult to obtain, this system should prove useful to answer a number of experimental questions regarding the biology of these cells. In addition, production of mature red blood cells from human embryonic stem cells is of great potential practical importance because it could eventually become an alternate source of cell for transfusion.

Ultrastructural demonstration of Cx43 gap junctions in induced pluripotent stem cells from human cord blood.

PubMed

Beckmann, Anja; Schubert, Madline; Hainz, Nadine; Haase, Alexandra; Martin, Ulrich; Tschernig, Thomas; Meier, Carola

2016-11-01

Gap junction proteins are essential for direct intercellular communication but also influence cellular differentiation and migration. The expression of various connexin gap junction proteins has been demonstrated in embryonic stem cells, with Cx43 being the most intensely studied. As Cx43 is the most prominent gap junction protein in the heart, cardiomyocyte-differentiated stem cells have been studied intensely. To date, however, little is known about the expression and the subcellular distribution of Cx43 in undifferentiated stem cells or about the structural arrangement of channels. We, therefore, here investigate expression of Cx43 in undifferentiated human cord-blood-derived induced pluripotent stem cells (hCBiPS2). For this purpose, we carried out quantitative real-time PCR and immunohistochemistry. For analysis of Cx43 ultrastructure and protein assembly, we performed freeze-fracture replica immunogold labeling (FRIL). Cx43 expression was detected at mRNA and protein level in hCBIPS2 cells. For the first time, ultrastructural data are presented on gap junction morphology in induced pluripotent stem (iPS) cells from cord blood: Our FRIL and electron microscopical analysis revealed the occurrence of gap junction plaques in undifferentiated iPS cells. In addition, these gap junctions were shown to contain the gap junction protein Cx43.

Synthetic niches for differentiation of human embryonic stem cells bypassing embryoid body formation.

PubMed

Liu, Yarong; Fox, Victoria; Lei, Yuning; Hu, Biliang; Joo, Kye-Il; Wang, Pin

2014-07-01

The unique self-renewal and pluripotency features of human embryonic stem cells (hESCs) offer the potential for unlimited development of novel cell therapies. Currently, hESCs are cultured and differentiated using methods, such as monolayer culture and embryoid body (EB) formation. As such, achieving efficient differentiation into higher order structures remains a challenge, as well as maintaining cell viability during differentiation into homogeneous cell populations. Here, we describe the application of highly porous polymer scaffolds as synthetic stem cell niches. Bypassing the EB formation step, these scaffolds are capable of three-dimensional culture of undifferentiated hESCs and subsequent directed differentiation into three primary germ layers. H9 hESCs were successfully maintained and proliferated in biodegradable polymer scaffolds based on poly (lactic-co-glycolic acid) (PLGA). The results showed that cells within PLGA scaffolds retained characteristics of undifferentiated pluripotent stem cells. Moreover, the scaffolds allowed differentiation towards the lineage of interest by the addition of growth factors to the culture system. The in vivo transplantation study revealed that the scaffolds could provide a microenvironment that enabled hESCs to interact with their surroundings, thereby promoting cell differentiation. Therefore, this approach, which provides a unique culture/differentiation system for hESCs, will find its utility in various stem cell-based tissue-engineering applications. © 2013 Wiley Periodicals, Inc.

Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

NASA Astrophysics Data System (ADS)

Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z.; Gimzewski, James K.; Nakano, Atsushi

2013-04-01

While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.

A Method to Identify and Isolate Pluripotent Human Stem Cells and Mouse Epiblast Stem Cells Using Lipid Body-Associated Retinyl Ester Fluorescence

PubMed Central

Muthusamy, Thangaselvam; Mukherjee, Odity; Menon, Radhika; Megha, P.B.; Panicker, Mitradas M.

2014-01-01

Summary We describe the use of a characteristic blue fluorescence to identify and isolate pluripotent human embryonic stem cells and human-induced pluripotent stem cells. The blue fluorescence emission (450–500 nm) is readily observed by fluorescence microscopy and correlates with the expression of pluripotency markers (OCT4, SOX2, and NANOG). It allows easy identification and isolation of undifferentiated human pluripotent stem cells, high-throughput fluorescence sorting and subsequent propagation. The fluorescence appears early during somatic reprogramming. We show that the blue fluorescence arises from the sequestration of retinyl esters in cytoplasmic lipid bodies. The retinoid-sequestering lipid bodies are specific to human and mouse pluripotent stem cells of the primed or epiblast-like state and absent in naive mouse embryonic stem cells. Retinol, present in widely used stem cell culture media, is sequestered as retinyl ester specifically by primed pluripotent cells and also can induce the formation of these lipid bodies. PMID:25068130

PRMT5 is essential for the maintenance of chondrogenic progenitor cells in the limb bud

PubMed Central

Norrie, Jacqueline L.; Li, Qiang; Co, Swanie; Huang, Bau-Lin; Ding, Ding; Uy, Jann C.; Ji, Zhicheng; Mackem, Susan; Bedford, Mark T.; Galli, Antonella; Ji, Hongkai

2016-01-01

During embryonic development, undifferentiated progenitor cells balance the generation of additional progenitor cells with differentiation. Within the developing limb, cartilage cells differentiate from mesodermal progenitors in an ordered process that results in the specification of the correct number of appropriately sized skeletal elements. The internal pathways by which these cells maintain an undifferentiated state while preserving their capacity to differentiate is unknown. Here, we report that the arginine methyltransferase PRMT5 has a crucial role in maintaining progenitor cells. Mouse embryonic buds lacking PRMT5 have severely truncated bones with wispy digits lacking joints. This novel phenotype is caused by widespread cell death that includes mesodermal progenitor cells that have begun to precociously differentiate into cartilage cells. We propose that PRMT5 maintains progenitor cells through its regulation of Bmp4. Intriguingly, adult and embryonic stem cells also require PRMT5 for maintaining pluripotency, suggesting that similar mechanisms might regulate lineage-restricted progenitor cells during organogenesis. PMID:27827819

PRMT5 is essential for the maintenance of chondrogenic progenitor cells in the limb bud.

PubMed

Norrie, Jacqueline L; Li, Qiang; Co, Swanie; Huang, Bau-Lin; Ding, Ding; Uy, Jann C; Ji, Zhicheng; Mackem, Susan; Bedford, Mark T; Galli, Antonella; Ji, Hongkai; Vokes, Steven A

2016-12-15

During embryonic development, undifferentiated progenitor cells balance the generation of additional progenitor cells with differentiation. Within the developing limb, cartilage cells differentiate from mesodermal progenitors in an ordered process that results in the specification of the correct number of appropriately sized skeletal elements. The internal pathways by which these cells maintain an undifferentiated state while preserving their capacity to differentiate is unknown. Here, we report that the arginine methyltransferase PRMT5 has a crucial role in maintaining progenitor cells. Mouse embryonic buds lacking PRMT5 have severely truncated bones with wispy digits lacking joints. This novel phenotype is caused by widespread cell death that includes mesodermal progenitor cells that have begun to precociously differentiate into cartilage cells. We propose that PRMT5 maintains progenitor cells through its regulation of Bmp4 Intriguingly, adult and embryonic stem cells also require PRMT5 for maintaining pluripotency, suggesting that similar mechanisms might regulate lineage-restricted progenitor cells during organogenesis. © 2016. Published by The Company of Biologists Ltd.

Mice cloned from skin cells.

PubMed

Li, Jinsong; Greco, Valentina; Guasch, Géraldine; Fuchs, Elaine; Mombaerts, Peter

2007-02-20

Adult stem cells represent unique populations of undifferentiated cells with self-renewal capacity. In many tissues, stem cells divide less often than their progeny. It has been widely speculated, but largely untested, that their undifferentiated and quiescent state may make stem cells more efficient as donors for cloning by nuclear transfer (NT). Here, we report the use of nuclei from hair follicle stem cells and other skin keratinocytes as NT donors. When keratinocyte stem cells (KSCs) were used as NT donors, 19 liveborn mice were obtained, 9 of which survived to adulthood. Embryonic keratinocytes and cumulus cells also gave rise to cloned mice. Although cloning efficiencies were similar (<6% per transferred blastocyst), success rates were consistently higher for males than for females. Adult keratinocyte stem cells were better NT donors than so-called transit amplifying (TA) keratinocytes in both sexes (1.6% vs. 0% in females and 5.4% vs. 2.8% in males). Our findings reveal skin as a source of readily accessible stem cells, the nuclei of which can be reprogrammed to the pluripotent state by exposure to the cytoplasm of unfertilized oocytes.

Behavior of Xeno-Transplanted Undifferentiated Human Induced Pluripotent Stem Cells Is Impacted by Microenvironment Without Evidence of Tumors.

PubMed

Martínez-Cerdeño, Veronica; Barrilleaux, Bonnie L; McDonough, Ashley; Ariza, Jeanelle; Yuen, Benjamin T K; Somanath, Priyanka; Le, Catherine T; Steward, Craig; Horton-Sparks, Kayla; Knoepfler, Paul S

2017-10-01

Human pluripotent stem cells (hPSC) have great clinical potential through the use of their differentiated progeny, a population in which there is some concern over risks of tumorigenicity or other unwanted cellular behavior due to residual hPSC. Preclinical studies using human stem cells are most often performed within a xenotransplant context. In this study, we sought to measure how undifferentiated hPSC behave following xenotransplant. We directly transplanted undifferentiated human induced pluripotent stem cells (hIPSC) and human embryonic stem cells (hESC) into the adult mouse brain ventricle and analyzed their fates. No tumors or precancerous lesions were present at more than one year after transplantation. This result differed with the tumorigenic capacity we observed after allotransplantation of mouse ESC into the mouse brain. A substantial population of cellular derivatives of undifferentiated hESC and hIPSC engrafted, survived, and migrated within the mouse brain parenchyma. Within brain structures, transplanted cell distribution followed a very specific pattern, suggesting the existence of distinct microenvironments that offer different degrees of permissibility for engraftment. Most of the transplanted hESC and hIPSC that developed into brain cells were NeuN+ neuronal cells, and no astrocytes were detected. Substantial cell and nuclear fusion occurred between host and transplanted cells, a phenomenon influenced by microenvironment. Overall, hIPSC appear to be largely functionally equivalent to hESC in vivo. Altogether, these data bring new insights into the behavior of stem cells without prior differentiation following xenotransplantation into the adult brain.

Autophagy in Human Embryonic Stem Cells

PubMed Central

Tra, Thien; Gong, Lan; Kao, Lin-Pin; Li, Xue-Lei; Grandela, Catarina; Devenish, Rodney J.; Wolvetang, Ernst; Prescott, Mark

2011-01-01

Autophagy (macroautophagy) is a degradative process that involves the sequestration of cytosolic material including organelles into double membrane vesicles termed autophagosomes for delivery to the lysosome. Autophagy is essential for preimplantation development of mouse embryos and cavitation of embryoid bodies. The precise roles of autophagy during early human embryonic development, remain however largely uncharacterized. Since human embryonic stem cells constitute a unique model system to study early human embryogenesis we investigated the occurrence of autophagy in human embryonic stem cells. We have, using lentiviral transduction, established multiple human embryonic stem cell lines that stably express GFP-LC3, a fluorescent marker for the autophagosome. Each cell line displays both a normal karyotype and pluripotency as indicated by the presence of cell types representative of the three germlayers in derived teratomas. GFP expression and labelling of autophagosomes is retained after differentiation. Baseline levels of autophagy detected in cultured undifferentiated hESC were increased or decreased in the presence of rapamycin and wortmannin, respectively. Interestingly, autophagy was upregulated in hESCs induced to undergo differentiation by treatment with type I TGF-beta receptor inhibitor SB431542 or removal of MEF secreted maintenance factors. In conclusion we have established hESCs capable of reporting macroautophagy and identify a novel link between autophagy and early differentiation events in hESC. PMID:22110659

Specific knockdown of Oct4 and beta2-microglobulin expression by RNA interference in human embryonic stem cells and embryonic carcinoma cells.

PubMed

Matin, Maryam M; Walsh, James R; Gokhale, Paul J; Draper, Jonathan S; Bahrami, Ahmad R; Morton, Ian; Moore, Harry D; Andrews, Peter W

2004-01-01

We have used RNA interference (RNAi) to downregulate beta2-microglobulin and Oct4 in human embryonal carcinoma (hEC) cells and embryonic stem (hES) cells, demonstrating that RNAi is an effective tool for regulating specific gene activity in these human stem cells. The knockdown of Oct4 but not beta2-microglobulin expression in both EC and ES cells resulted in their differentiation, as indicated by a marked change in morphology, growth rate, and surface antigen phenotype, with respect to SSEA1, SSEA3, and TRA-1-60 expression. Expression of hCG and Gcm1 was also induced following knockdown of Oct4 expression, in both 2102Ep hEC cells and in H7 and H14 hES cells, consistent with the conclusion that, as in the mouse, Oct4 is required to maintain the undifferentiated stem cell state, and that differentiation to trophectoderm occurs in its absence. NTERA2 hEC cells also differentiated, but not to trophectoderm, suggesting their equivalence to a later stage of embryogenesis than other hEC and hES cells.

Label-free separation of human embryonic stem cells and their differentiating progenies by phasor fluorescence lifetime microscopy

NASA Astrophysics Data System (ADS)

Stringari, Chiara; Sierra, Robert; Donovan, Peter J.; Gratton, Enrico

2012-04-01

We develop a label-free optical technique to image and discriminate undifferentiated human embryonic stem cells (hESCs) from their differentiating progenies in vitro. Using intrinsic cellular fluorophores, we perform fluorescence lifetime microscopy (FLIM) and phasor analysis to obtain hESC metabolic signatures. We identify two optical biomarkers to define the differentiation status of hESCs: Nicotinamide adenine dinucleotide (NADH) and lipid droplet-associated granules (LDAGs). These granules have a unique lifetime signature and could be formed by the interaction of reactive oxygen species and unsaturated metabolic precursor that are known to be abundant in hESC. Changes in the relative concentrations of these two intrinsic biomarkers allow for the discrimination of undifferentiated hESCs from differentiating hESCs. During early hESC differentiation we show that NADH concentrations increase, while the concentration of LDAGs decrease. These results are in agreement with a decrease in oxidative phosphorylation rate. Single-cell phasor FLIM signatures reveal an increased heterogeneity in the metabolic states of differentiating H9 and H1 hESC colonies. This technique is a promising noninvasive tool to monitor hESC metabolism during differentiation, which can have applications in high throughput analysis, drug screening, functional metabolomics and induced pluripotent stem cell generation.

Embryonic origin of adult stem cells required for tissue homeostasis and regeneration

PubMed Central

Davies, Erin L; Lei, Kai; Seidel, Christopher W; Kroesen, Amanda E; McKinney, Sean A; Guo, Longhua; Robb, Sofia MC; Ross, Eric J; Gotting, Kirsten; Alvarado, Alejandro Sánchez

2017-01-01

Planarian neoblasts are pluripotent, adult somatic stem cells and lineage-primed progenitors that are required for the production and maintenance of all differentiated cell types, including the germline. Neoblasts, originally defined as undifferentiated cells residing in the adult parenchyma, are frequently compared to embryonic stem cells yet their developmental origin remains obscure. We investigated the provenance of neoblasts during Schmidtea mediterranea embryogenesis, and report that neoblasts arise from an anarchic, cycling piwi-1+ population wholly responsible for production of all temporary and definitive organs during embryogenesis. Early embryonic piwi-1+ cells are molecularly and functionally distinct from neoblasts: they express unique cohorts of early embryo enriched transcripts and behave differently than neoblasts in cell transplantation assays. Neoblast lineages arise as organogenesis begins and are required for construction of all major organ systems during embryogenesis. These subpopulations are continuously generated during adulthood, where they act as agents of tissue homeostasis and regeneration. DOI: http://dx.doi.org/10.7554/eLife.21052.001 PMID:28072387

Developmental Competence of Buffalo (Bubalus bubalis) Pluripotent Embryonic Stem Cells Over Different Homologous Feeder Layers and the Comparative Evaluation with Various Extracellular Matrices.

PubMed

Sharma, Manjinder; Dubey, Pawan K; Kumar, Rajesh; Nath, Amar; Kumar, G Sai; Sharma, G Taru

2013-05-01

Use of somatic cells as a feeder layer to maintain the embryonic stem cells (ESCs) in undifferentiated state limits the stem cell research design, since experimental data may result from a combined ESCs and feeder cell response to various stimuli. Therefore, present study was designed to evaluate the developmental competence of the buffalo ESCs over different homogenous feeders and compare with various extracellular matrices using different concentrations of LIF. Inner cell masses (ICMs) of in vitro hatched blastocysts were cultured onto homologous feeders viz. fetal fibroblast, granulosa and oviductal cell feeder layers and synthetic matrices viz. fibronectin, collagen type I and matrigel in culture medium. Developmental efficiency was found higher for ESCs cultured on fetal fibroblast and granulosa layers (83.33%) followed by fibronectin (77.78%) at 30 ng LIF. Oviductal feeder was found to be the least efficient feeder showing only 11.11% undifferentiated primary ESC colonies at 30 ng LIF. However, neither feeder layer nor synthetic matrix could support the development of primary colonies at 10 ng LIF. Expression of SSEA- 4, TRA-1-60 and Oct-4 were found positive in ESC colonies from all the feeders and synthetic matrices with 20 ng and 30 ng LIF. Fetal fibroblast and granulosa cell while, amongst synthetic matrices, fibronectin were found to be equally efficient to support the growth and maintenance of ESCs pluripotency with 30 ng LIF. This well-defined culture conditions may provide an animal model for culturing human embryonic stem cells in the xeno-free or feeder-free conditions for future clinical applications.

Zscan4 is regulated by PI3-kinase and DNA-damaging agents and directly interacts with the transcriptional repressors LSD1 and CtBP2 in mouse embryonic stem cells.

PubMed

Storm, Michael P; Kumpfmueller, Benjamin; Bone, Heather K; Buchholz, Michael; Sanchez Ripoll, Yolanda; Chaudhuri, Julian B; Niwa, Hitoshi; Tosh, David; Welham, Melanie J

2014-01-01

The Zscan4 family of genes, encoding SCAN-domain and zinc finger-containing proteins, has been implicated in the control of early mammalian embryogenesis as well as the regulation of pluripotency and maintenance of genome integrity in mouse embryonic stem cells. However, many features of this enigmatic family of genes are poorly understood. Here we show that undifferentiated mouse embryonic stem cell (ESC) lines simultaneously express multiple members of the Zscan4 gene family, with Zscan4c, Zscan4f and Zscan4-ps2 consistently being the most abundant. Despite this, between only 0.1 and 0.7% of undifferentiated mouse pluripotent stem cells express Zscan4 protein at a given time, consistent with a very restricted pattern of Zscan4 transcripts reported previously. Herein we demonstrate that Zscan4 expression is regulated by the p110α catalytic isoform of phosphoinositide 3-kinases and is induced following exposure to a sub-class of DNA-damage-inducing agents, including Zeocin and Cisplatin. Furthermore, we observe that Zscan4 protein expression peaks during the G2 phase of the cell cycle, suggesting that it may play a critical role at this checkpoint. Studies with GAL4-fusion proteins suggest a role for Zscan4 in transcriptional regulation, further supported by the fact that protein interaction analyses demonstrate that Zscan4 interacts with both LSD1 and CtBP2 in ESC nuclei. This study advances and extends our understanding of Zscan4 expression, regulation and mechanism of action. Based on our data we propose that Zscan4 may regulate gene transcription in mouse ES cells through interaction with LSD1 and CtBP2.

Zscan4 Is Regulated by PI3-Kinase and DNA-Damaging Agents and Directly Interacts with the Transcriptional Repressors LSD1 and CtBP2 in Mouse Embryonic Stem Cells

PubMed Central

Bone, Heather K.; Buchholz, Michael; Sanchez Ripoll, Yolanda; Chaudhuri, Julian B.; Niwa, Hitoshi; Tosh, David; Welham, Melanie J.

2014-01-01

The Zscan4 family of genes, encoding SCAN-domain and zinc finger-containing proteins, has been implicated in the control of early mammalian embryogenesis as well as the regulation of pluripotency and maintenance of genome integrity in mouse embryonic stem cells. However, many features of this enigmatic family of genes are poorly understood. Here we show that undifferentiated mouse embryonic stem cell (ESC) lines simultaneously express multiple members of the Zscan4 gene family, with Zscan4c, Zscan4f and Zscan4-ps2 consistently being the most abundant. Despite this, between only 0.1 and 0.7% of undifferentiated mouse pluripotent stem cells express Zscan4 protein at a given time, consistent with a very restricted pattern of Zscan4 transcripts reported previously. Herein we demonstrate that Zscan4 expression is regulated by the p110α catalytic isoform of phosphoinositide 3-kinases and is induced following exposure to a sub-class of DNA-damage-inducing agents, including Zeocin and Cisplatin. Furthermore, we observe that Zscan4 protein expression peaks during the G2 phase of the cell cycle, suggesting that it may play a critical role at this checkpoint. Studies with GAL4-fusion proteins suggest a role for Zscan4 in transcriptional regulation, further supported by the fact that protein interaction analyses demonstrate that Zscan4 interacts with both LSD1 and CtBP2 in ESC nuclei. This study advances and extends our understanding of Zscan4 expression, regulation and mechanism of action. Based on our data we propose that Zscan4 may regulate gene transcription in mouse ES cells through interaction with LSD1 and CtBP2. PMID:24594919

Survival, migration, and differentiation of Sox1-GFP embryonic stem cells in coculture with an auditory brainstem slice preparation.

PubMed

Glavaski-Joksimovic, Aleksandra; Thonabulsombat, Charoensri; Wendt, Malin; Eriksson, Mikael; Palmgren, Björn; Jonsson, Anna; Olivius, Petri

2008-03-01

The poor regeneration capability of the mammalian hearing organ has initiated different approaches to enhance its functionality after injury. To evaluate a potential neuronal repair paradigm in the inner ear and cochlear nerve we have previously used embryonic neuronal tissue and stem cells for implantation in vivo and in vitro. At present, we have used in vitro techniques to study the survival and differentiation of Sox1-green fluorescent protein (GFP) mouse embryonic stem (ES) cells as a monoculture or as a coculture with rat auditory brainstem slices. For the coculture, 300 microm-thick brainstem slices encompassing the cochlear nucleus and cochlear nerve were prepared from postnatal SD rats. The slices were propagated using the membrane interface method and the cochlear nuclei were prelabeled with DiI. After some days in culture a suspension of Sox1 cells was deposited next to the brainstem slice. Following deposition Sox1 cells migrated toward the brainstem and onto the cochlear nucleus. GFP was not detectable in undifferentiated ES cells but became evident during neural differentiation. Up to 2 weeks after transplantation the cocultures were fixed. The undifferentiated cells were evaluated with antibodies against progenitor cells whereas the differentiated cells were determined with neuronal and glial markers. The morphological and immunohistochemical data indicated that Sox1 cells in monoculture differentiated into a higher percentage of glial cells than neurons. However, when a coculture was used a significantly lower percentage of Sox1 cells differentiated into glial cells. The results demonstrate that a coculture of Sox1 cells and auditory brainstem present a useful model to study stem cell differentiation.

Characterization and comparison of osteoblasts derived from mouse embryonic stem cells and induced pluripotent stem cells.

PubMed

Ma, Ming-San; Kannan, Vishnu; de Vries, Anneriek E; Czepiel, Marcin; Wesseling, Evelyn M; Balasubramaniyan, Veerakumar; Kuijer, Roel; Vissink, Arjan; Copray, Sjef C V M; Raghoebar, Gerry M

2017-01-01

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 therefore do not raise ethical concerns. Proper characterization of iPS-derived osteoblasts is important for future development of safe clinical applications of these cells. For this reason, we differentiated mouse ES and iPS cells toward osteoblasts using osteogenic medium and compared their functionality. Immunocytochemical analysis showed significant expression of bone markers (osteocalcin and collagen type I) in osteoblasts differentiated from ES and iPS cells on days 7 and 30. An in vitro mineralization assay confirmed the functionality of osteogenically differentiated ES and iPS cells. Gene expression arrays focusing on osteogenic differentiation were performed in order to compare the gene expression pattern in both differentiated and undifferentiated ES cells and iPS cells. We observed a significant upregulation of osteogenesis-related genes such as Runx2, osteopontin, collagen type I, Tnfsf11, Csf1, and alkaline phosphatase upon osteogenic differentiation of the ES and iPS cells. We further validated the expression of key osteogenic genes Runx2, osteopontin, osteocalcin, collagen type I, and osterix in both differentiated and undifferentiated ES and iPS cells by means of quantified real-time polymerase chain reaction. We conclude that ES and iPS cells are similar in their osteogenic differentiation capacities, as well as in their gene expression patterns.

Ultrastructural characteristics of three undifferentiated mouse embryonic stem cell lines and their differentiated three-dimensional derivatives: a comparative study.

PubMed

Alharbi, Suzan; Elsafadi, Mona; Mobarak, Mohammed; Alrwili, Ali; Vishnubalaji, Radhakrishnan; Manikandan, Muthurangan; Al-Qudsi, Fatma; Karim, Saleh; Al-Nabaheen, May; Aldahmash, Abdullah; Mahmood, Amer

2014-04-01

The fine structures of mouse embryonic stem cells (mESCs) grown as colonies and differentiated in three-dimensional (3D) culture as embryoid bodies (EBs) were analyzed by transmission electron microscopy. Undifferentiated mESCs expressed markers that proved their pluripotency. Differentiated EBs expressed different differentiation marker proteins from the three germ layers. The ultrastructure of mESCs revealed the presence of microvilli on the cell surfaces, large and deep infolded nuclei, low cytoplasm-to-nuclear ratios, frequent lipid droplets, nonprominent Golgi apparatus, and smooth endoplasmic reticulum. In addition, we found prominent juvenile mitochondria and free ribosomes-rich cytoplasm in mESCs. Ultrastructure of the differentiated mESCs as EBs showed different cell arrangements, which indicate the different stages of EB development and differentiation. The morphologies of BALB/c and 129 W9.5 EBs were very similar at day 4, whereas C57BL/6 EBs were distinct from the others at day 4. This finding suggested that differentiation of EBs from different cell lines occurs in the same pattern but not at the same rate. Conversely, the ultrastructure results of BALB/c and 129 W9.5 ESCs revealed differentiating features, such as the dilated profile of a rough endoplasmic reticulum. In addition, we found low expression levels of undifferentiated markers on the outer cells of BALB/c and 129 W9.5 mESC colonies, which suggests a faster differentiation potential.

Chromatin remodeling in stem cell maintenance in Arabidopsis thaliana.

PubMed

Shen, Wen-Hui; Xu, Lin

2009-07-01

Pluripotent stem cells are able to both self-renew and generate undifferentiated cells for the formation of new tissues and organs. In higher plants, stem cells found in the shoot apical meristem (SAM) and the root apical meristem (RAM) are origins of organogenesis occurring post-embryonically. It is important to understand how the regulation of stem cell fate is coordinated to enable the meristem to constantly generate different types of lateral organs. Much knowledge has accumulated on specific transcription factors controlling SAM and RAM activity. Here, we review recent evidences for a role of chromatin remodeling in the maintenance of stable expression states of transcription factor genes and the control of stem cell activity in Arabidopsis.

Lamin A/C Haploinsufficiency Modulates the Differentiation Potential of Mouse Embryonic Stem Cells

PubMed Central

Sehgal, Poonam; Chaturvedi, Pankaj; Kumaran, R. Ileng; Kumar, Satish; Parnaik, Veena K.

2013-01-01

Background Lamins are structural proteins that are the major determinants of nuclear architecture and play important roles in various nuclear functions including gene regulation and cell differentiation. Mutations in the human lamin A gene cause a spectrum of genetic diseases that affect specific tissues. Most available mouse models for laminopathies recapitulate disease symptoms for muscle diseases and progerias. However, loss of human lamin A/C also has highly deleterious effects on fetal development. Hence it is important to understand the impact of lamin A/C expression levels on embryonic differentiation pathways. Methodology and Principal Findings We have investigated the differentiation potential of mouse embryonic stem cells containing reduced levels of lamin A/C by detailed lineage analysis of embryoid bodies derived from these cells by in vitro culture. We initially carried out a targeted disruption of one allele of the mouse lamin A/C gene (Lmna). Undifferentiated wild-type and Lmna+/− embryonic stem cells showed similar expression of pluripotency markers and cell cycle profiles. Upon spontaneous differentiation into embryoid bodies, markers for visceral endoderm such as α-fetoprotein were highly upregulated in haploinsufficient cells. However, neuronal markers such as β-III tubulin and nestin were downregulated. Furthermore, we observed a reduction in the commitment of Lmna+/− cells into the myogenic lineage, but no discernible effects on cardiac, adipocyte or osteocyte lineages. In the next series of experiments, we derived embryonic stem cell clones expressing lamin A/C short hairpin RNA and examined their differentiation potential. These cells expressed pluripotency markers and, upon differentiation, the expression of lineage-specific markers was altered as observed with Lmna+/− embryonic stem cells. Conclusions We have observed significant effects on embryonic stem cell differentiation to visceral endoderm, neuronal and myogenic lineages upon depletion of lamin A/C. Hence our results implicate lamin A/C level as an important determinant of lineage-specific differentiation during embryonic development. PMID:23451281

Podocalyxin as a major pluripotent marker and novel keratan sulfate proteoglycan in human embryonic and induced pluripotent stem cells.

PubMed

Toyoda, Hidenao; Nagai, Yuko; Kojima, Aya; Kinoshita-Toyoda, Akiko

2017-04-01

Podocalyxin (PC) was first identified as a heavily sialylated transmembrane protein of glomerular podocytes. Recent studies suggest that PC is a remarkable glycoconjugate that acts as a universal glyco-carrier. The glycoforms of PC are responsible for multiple functions in normal tissue, human cancer cells, human embryonic stem cells (hESCs), and human induced pluripotent stem cells (hiPSCs). PC is employed as a major pluripotent marker of hESCs and hiPSCs. Among the general antibodies for human PC, TRA-1-60 and TRA-1-81 recognize the keratan sulfate (KS)-related structures. Therefore, It is worthwhile to summarize the outstanding chemical characteristic of PC, including the KS-related structures. Here, we review the glycoforms of PC and discuss the potential of PC as a novel KS proteoglycan in undifferentiated hESCs and hiPSCs.

Wnt/β-catenin and LIF-Stat3 signaling pathways converge on Sp5 to promote mouse embryonic stem cell self-renewal.

PubMed

Ye, Shoudong; Zhang, Dongming; Cheng, Fei; Wilson, Daniel; Mackay, Jeffrey; He, Kan; Ban, Qian; Lv, Feng; Huang, Saifei; Liu, Dahai; Ying, Qi-Long

2016-01-15

Activation of leukemia inhibitor factor (LIF)-Stat3 or Wnt/β-catenin signaling promotes mouse embryonic stem cell (mESC) self-renewal. A myriad of downstream targets have been identified in the individual signal pathways, but their common targets remain largely elusive. In this study, we found that the LIF-Stat3 and Wnt/β-catenin signaling pathways converge on Sp5 to promote mESC self-renewal. Forced Sp5 expression can reproduce partial effects of Wnt/β-catenin signaling but mimics most features of LIF-Stat3 signaling to maintain undifferentiated mESCs. Moreover, Sp5 is able to convert mouse epiblast stem cells into a naïve pluripotent state. Thus, Sp5 is an important component of the regulatory network governing mESC naïve pluripotency. © 2016. Published by The Company of Biologists Ltd.

Cell cycle regulation in human embryonic stem cells: links to adaptation to cell culture.

PubMed

Barta, Tomas; Dolezalova, Dasa; Holubcova, Zuzana; Hampl, Ales

2013-03-01

Cell cycle represents not only a tightly orchestrated mechanism of cell replication and cell division but it also plays an important role in regulation of cell fate decision. Particularly in the context of pluripotent stem cells or multipotent progenitor cells, regulation of cell fate decision is of paramount importance. It has been shown that human embryonic stem cells (hESCs) show unique cell cycle characteristics, such as short doubling time due to abbreviated G1 phase; these properties change with the onset of differentiation. This review summarizes the current understanding of cell cycle regulation in hESCs. We discuss cell cycle properties as well as regulatory machinery governing cell cycle progression of undifferentiated hESCs. Additionally, we provide evidence that long-term culture of hESCs is accompanied by changes in cell cycle properties as well as configuration of several cell cycle regulatory molecules.

Identification and Single-Cell Functional Characterization of an Endodermally Biased Pluripotent Substate in Human Embryonic Stem Cells.

PubMed

Allison, Thomas F; Smith, Andrew J H; Anastassiadis, Konstantinos; Sloane-Stanley, Jackie; Biga, Veronica; Stavish, Dylan; Hackland, James; Sabri, Shan; Langerman, Justin; Jones, Mark; Plath, Kathrin; Coca, Daniel; Barbaric, Ivana; Gokhale, Paul; Andrews, Peter W

2018-05-09

Human embryonic stem cells (hESCs) display substantial heterogeneity in gene expression, implying the existence of discrete substates within the stem cell compartment. To determine whether these substates impact fate decisions of hESCs we used a GFP reporter line to investigate the properties of fractions of putative undifferentiated cells defined by their differential expression of the endoderm transcription factor, GATA6, together with the hESC surface marker, SSEA3. By single-cell cloning, we confirmed that substates characterized by expression of GATA6 and SSEA3 include pluripotent stem cells capable of long-term self-renewal. When clonal stem cell colonies were formed from GATA6-positive and GATA6-negative cells, more of those derived from GATA6-positive cells contained spontaneously differentiated endoderm cells than similar colonies derived from the GATA6-negative cells. We characterized these discrete cellular states using single-cell transcriptomic analysis, identifying a potential role for SOX17 in the establishment of the endoderm-biased stem cell state. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Acellular Mouse Kidney ECM can be Used as a Three-Dimensional Substrate to Test the Differentiation Potential of Embryonic Stem Cell Derived Renal Progenitors.

PubMed

Sambi, Manpreet; Chow, Theresa; Whiteley, Jennifer; Li, Mira; Chua, Shawn; Raileanu, Vanessa; Rogers, Ian M

2017-08-01

The development of strategies for tissue regeneration and bio-artificial organ development is based on our understanding of embryogenesis. Differentiation protocols attempt to recapitulate the signaling modalities of gastrulation and organogenesis, coupled with cell selection regimens to isolate the cells of choice. This strategy is impeded by the lack of optimal in vitro culture systems since traditional culture systems do not allow for the three-dimensional interaction between cells and the extracellular matrix. While artificial three-dimensional scaffolds are available, using the natural extracellular matrix scaffold is advantageous because it has a distinct architecture that is difficult to replicate. The adult extracellular matrix is predicted to mediate signaling related to tissue repair not embryogenesis but existing similarities between the two argues that the extracellular matrix will influence the differentiation of stem and progenitor cells. Previous studies using undifferentiated embryonic stem cells grown directly on acellular kidney ECM demonstrated that the acellular kidney supported cell growth but limited differentiation occurred. Using mouse kidney extracellular matrix and mouse embryonic stem cells we report that the extracellular matrix can support the development of kidney structures if the stem cells are first differentiated to kidney progenitor cells before being applied to the acellular organ.

GROα regulates human embryonic stem cell self-renewal or adoption of a neuronal fate

PubMed Central

Krtolica, Ana; Larocque, Nick; Genbacev, Olga; Ilic, Dusko; Coppe, Jean-Philippe; Patil, Christopher K.; Zdravkovic, Tamara; McMaster, Michael; Campisi, Judith; Fisher, Susan J.

2012-01-01

Previously we reported that feeders formed from human placental fibroblasts (hPFs) support derivation and long-term self-renewal of human embryonic stem cells (hESCs) under serum-free conditions. Here, we show, using antibody array and ELISA platforms, that hPFs secrete ~6-fold higher amounts of the CXC-type chemokine, GROα, than IMR 90, a human lung fibroblast line, which does not support hESC growth. Furthermore, immunocytochemistry and immunoblot approaches revealed that hESCs express CXCR, a GROα receptor. We used this information to develop defined culture medium for feeder-free propagation of hESCs in an undifferentiated state. Cells passaged as small aggregates and maintained in the GROα-containing medium had a normal karyotype, expressed pluripotency markers, and exhibited apical–basal polarity, i.e., had the defining features of pluripotent hESCs. They also differentiated into the three primary (embryonic) germ layers and formed teratomas in immunocompromised mice. hESCs cultured as single cells in the GROα-containing medium also had a normal karyotype, but they downregulated markers of pluripotency, lost apical–basal polarity, and expressed markers that are indicative of the early stages of neuronal differentiation—βIII tubulin, vimentin, radial glial protein, and nestin. These data support our hypothesis that establishing and maintaining cell polarity is essential for the long-term propagation of hESCs in an undifferentiated state and that disruption of cell–cell contacts can trigger adoption of a neuronal fate. PMID:21396766

Derivation of porcine pluripotent stem cells for biomedical research.

PubMed

Shiue, Yow-Ling; Yang, Jenn-Rong; Liao, Yu-Jing; Kuo, Ting-Yung; Liao, Chia-Hsin; Kang, Ching-Hsun; Tai, Chein; Anderson, Gary B; Chen, Lih-Ren

2016-07-01

Pluripotent stem cells including embryonic stem cells (ESCs), embryonic germ cells (EGCs), and induced pluripotent stem cells (iPSCs) are capable of self-renew and limitlessly proliferating in vitro with undifferentiated characteristics. They are able to differentiate in vitro, spontaneously or responding to suitable signals, into cells of all three primary germ layers. Consequently, these pluripotent stem cells will be valuable sources for cell replacement therapy in numerous disorders. However, the promise of human ESCs and EGCs is cramped by the ethical argument about destroying embryos and fetuses for cell line creation. Moreover, there are still carcinogenic risks existing toward the goal of clinical application for human ESCs, EGCs, and iPSCs. Therefore, a suitable animal model for stem cell research will benefit the further development of human stem cell technology. The pigs, on the basis of their similarity in anatomy, immunology, physiology, and biochemical properties, have been wide used as model animals in the study of various human diseases. The development of porcine pluripotent stem cell lines will hold the opportunity to provide an excellent material for human counterpart to the transplantation in biomedical research and further development of cell-based therapeutic strategy. Copyright © 2016 Elsevier Inc. All rights reserved.

Thalidomide induces apoptosis in undifferentiated human induced pluripotent stem cells.

PubMed

Tachikawa, Saoko; Nishimura, Toshinobu; Nakauchi, Hiromitsu; Ohnuma, Kiyoshi

2017-10-01

Thalidomide, which was formerly available commercially to control the symptoms of morning sickness, is a strong teratogen that causes fetal abnormalities. However, the mechanism of thalidomide teratogenicity is not fully understood; thalidomide toxicity is not apparent in rodents, and the use of human embryos is ethically and technically untenable. In this study, we designed an experimental system featuring human-induced pluripotent stem cells (hiPSCs) to investigate the effects of thalidomide. These cells exhibit the same characteristics as those of epiblasts originating from implanted fertilized ova, which give rise to the fetus. Therefore, theoretically, thalidomide exposure during hiPSC differentiation is equivalent to that in the human fetus. We examined the effects of thalidomide on undifferentiated hiPSCs and early-differentiated hiPSCs cultured in media containing bone morphogenetic protein-4, which correspond, respectively, to epiblast (future fetus) and trophoblast (future extra-embryonic tissue). We found that only the number of undifferentiated cells was reduced. In undifferentiated cells, application of thalidomide increased the number of apoptotic and dead cells at day 2 but not day 4. Application of thalidomide did not affect the cell cycle. Furthermore, immunostaining and flow cytometric analysis revealed that thalidomide exposure had no effect on the expression of specific markers of undifferentiated and early trophectodermal differentiated cells. These results suggest that the effect of thalidomide was successfully detected in our experimental system and that thalidomide eliminated a subpopulation of undifferentiated hiPSCs. This study may help to elucidate the mechanisms underlying thalidomide teratogenicity and reveal potential strategies for safely prescribing this drug to pregnant women.

Heat shock 70-kDa protein 8 isoform 1 is expressed on the surface of human embryonic stem cells and downregulated upon differentiation.

PubMed

Son, Yeon Sung; Park, Jae Hyun; Kang, Young Kook; Park, Jin-Sung; Choi, Hong Seo; Lim, Ji Young; Lee, Jeoung Eun; Lee, Jung Bok; Ko, Myoung Seok; Kim, Yong-Sam; Ko, Jeong-Heon; Yoon, Hyun Soo; Lee, Kwang-Woong; Seong, Rho Hyun; Moon, Shin Yong; Ryu, Chun Jeih; Hong, Hyo Jeong

2005-01-01

The cell-surface markers used routinely to define the undifferentiated state and pluripotency of human embryonic stem cells (hESCs) are those used in mouse embryonic stem cells (mESCs) because of a lack of markers directly originated from hESC itself. To identify more hESC-specific cell-surface markers, we generated a panel of monoclonal antibodies (MAbs) by immunizing the irradiated cell clumps of hESC line Miz-hES1, and selected 26 MAbs that were able to bind to Miz-hES1 cells but not to mESCs, mouse embryonic fibroblast cells, and STO cells. Most antibodies did not bind to human neural progenitor cells derived from the Miz-hES1 cells, either. Of these, MAb 20-202S (IgG1, kappa) immunoprecipitated a cell-surface protein of 72-kDa from the lysate of biotin-labeled Miz-hES1 cells, which was identified to be heat shock 70-kDa protein 8 isoform 1 (HSPA8) by quadrupole time-of-flight tandem mass spectrometry. Immunocytochemical analyses proved that the HSPA8 protein was also present on the surface of hESC lines Miz-hES4, Miz-hES6, and HSF6. Two-color flow cytometric analysis of Miz-hES1 and HSF6 showed the coexpression of the HSPA8 protein with other hESC markers such as stage-specific embryonic antigen 3 (SSEA3), SSEA4, TRA-1-60, and TRA-1-81. Flow cytometric and Western blot analyses using various cells showed that MAb 20-202S specifically bound to the HSPA8 protein on the surface of Miz-hES1, contrary to other anti-HSP70 antibodies examined. Furthermore, the surface expression of the HSPA8 protein on Miz-hES1 was markedly downregulated upon differentiation. These data indicate that a novel MAb 20-202S recognizes the HSPA8 protein on the surface of hESCs and suggest that the HSPA8 protein is a putative cell-surface marker for undifferentiated hESCs.

Establishment of stem cell lines from nuclear transferred and parthenogenetically activated mouse oocytes for therapeutic cloning.

PubMed

Ju, Jin Young; Park, Chun Young; Gupta, Mukesh Kumar; Uhm, Sang Jun; Paik, Eun Chan; Ryoo, Zae Young; Cho, Youl Hee; Chung, Kil Saeng; Lee, Hoon Taek

2008-05-01

To establish embryonic stem cell lines from nuclear transfer of somatic cell nuclei isolated from the same oocyte donor and from parthenogenetic activation. The study also evaluated the effect of the micromanipulation procedure on the outcome of somatic cell nuclear transfer in mice. Randomized, prospective study. Hospital-based assisted reproductive technology laboratory. F(1) (C57BL/6 x 129P3/J) mice. Metaphase II-stage oocytes were either parthenogenetically activated or nuclear transferred with cumulus cell nuclei or parthenogenetically activated after a sham-manipulation procedure. Embryogenesis and embryonic stem cell establishment. The development rate to morula/blastocyst of nuclear transferred oocytes (27.9% +/- 5.9%) was significantly lower than that of the sham-manipulated (84.1% +/- 5.6%) or parthenogenetic (98.6% +/- 1.4%) groups. A sharp decrease in cleavage potential was obvious in the two- to four-cell transition for the nuclear transferred embryos (79.0% +/- 4.6% and 43.3% +/- 5.0%), implying incomplete nuclear reprogramming in arrested oocytes. However, the cleavage, as well as the development rate, of parthenogenetic and sham-manipulated groups did not differ significantly. The embryonic stem cell line establishment rate was higher from parthenogenetically activated oocytes (15.7%) than nuclear transferred (4.3%) or sham-manipulated oocytes (12.5%). Cell colonies from all groups displayed typical morphology of mice embryonic stem cells and could be maintained successfully with undifferentiated morphology after continuous proliferation for more than 120 passages still maintaining normal karyotype. All these cells were positive for mice embryonic stem cell markers such as Oct-4 and SSEA-1 based on immunocytochemistry and reverse transcriptase-polymerase chain reaction. The clonal origin of the ntES cell line and the parthenogenetic embryonic stem cell lines were confirmed by polymerase chain reaction analysis of the polymorphic markers. Blastocyst injection experiments demonstrated that these lines contributed to resulting chimeras and are germ-line competent. We report the establishment of ntES cell lines from somatic cells isolated from same individual. Our data also suggest that embryo micromanipulation procedure during the nuclear transfer procedure influences the developmental ability and embryonic stem cell establishment rate of nuclear transferred embryos.

Seven diverse human embryonic stem cell-derived chondrogenic clonal embryonic progenitor cell lines display site-specific cell fates.

PubMed

Sternberg, Hal; Kidd, Jennifer; Murai, James T; Jiang, Jianjie; Rinon, Ariel; Erickson, Isaac E; Funk, Walter D; Wang, Qian; Chapman, Karen B; Vangsness, C Thomas; West, Michael D

2013-03-01

The transcriptomes of seven diverse clonal human embryonic progenitor cell lines with chondrogenic potential were compared with that of bone marrow-derived mesenchymal stem cells (MSCs). The cell lines 4D20.8, 7PEND24, 7SMOO32, E15, MEL2, SK11 and SM30 were compared with MSCs using immunohistochemical methods, gene expression microarrays and quantitative real-time PCR. In the undifferentiated progenitor state, each line displayed unique combinations of site-specific markers, including AJAP1, ALDH1A2, BMP5, BARX1, HAND2, HOXB2, LHX1, LHX8, PITX1, TBX15 and ZIC2, but none of the lines expressed the MSC marker CD74. The lines showed diverse responses when differentiated in the presence of combinations of TGF-β3, BMP2, 4, 6 and 7 and GDF5, with the lines 4D20.8, SK11, SM30 and MEL2 showing osteogenic markers in some differentiation conditions. The line 7PEND24 showed evidence of regenerating articular cartilage and, in some conditions, markers of tendon differentiation. The scalability of site-specific clonal human embryonic stem cell-derived embryonic progenitor cell lines may provide novel models for the study of differentiation and methods for preparing purified and identified cells types for use in therapy.

Conference Scene: Induced pluripotent cells: a new path for regenerative medicine. 7 October 2010, BioPark, Welwyn Garden City, Hertfordshire, UK.

PubMed

Crutzen, Hélène S G

2011-01-01

Embryonic stem cells and induced pluripotent stem (iPS) cells, which are embryonic stem-like cells derived from adult tissues, have the broadest differentiation potential. These cells are unique in their ability to self-renew, to be maintained in an undifferentiated state for long periods of culturing and to give rise to many different cell lineages including germ-line cells. They therefore represent an invaluable tool for facilitating research towards the realization of regenerative medicine. The recent developments in embryonic stem cell and iPS cell technology have allowed human cell models to be developed that will hopefully provide novel platforms for disease analysis not only at the basic science level, but also for drug discovery and screening, and other clinical applications. This 1-day conference, chaired by Professor Peter Andrews from the University of Sheffield, UK, and Dr Chris Denning from the University of Nottingham, UK, focused on generation of iPS cells, their differentiation into specific fates and applications to disease modeling. It consisted of 11 talks by UK-based and international researchers, and three posters; Ms Azra Fatima from Cologne University, Germany, won the competition for her poster on the derivation of iPS cells from a patient with arrhythmogenic right ventricular cardiomyopathy.

Human embryonic stem cell-derived neural crest cells capable of expressing markers of osteochondral or meningeal-choroid plexus differentiation.

PubMed

Sternberg, Hal; Jiang, Jianjie; Sim, Pamela; Kidd, Jennifer; Janus, Jeffrey; Rinon, Ariel; Edgar, Ron; Shitrit, Alina; Larocca, David; Chapman, Karen B; Binette, Francois; West, Michael D

2014-01-01

The transcriptome and fate potential of three diverse human embryonic stem cell-derived clonal embryonic progenitor cell lines with markers of cephalic neural crest are compared when differentiated in the presence of combinations of TGFβ3, BMP4, SCF and HyStem-C matrices. The cell lines E69 and T42 were compared with MEL2, using gene expression microarrays, immunocytochemistry and ELISA. In the undifferentiated progenitor state, each line displayed unique markers of cranial neural crest including TFAP2A and CD24; however, none expressed distal HOX genes including HOXA2 or HOXB2, or the mesenchymal stem cell marker CD74. The lines also showed diverse responses when differentiated in the presence of exogenous BMP4, BMP4 and TGFβ3, SCF, and SCF and TGFβ3. The clones E69 and T42 showed a profound capacity for expression of endochondral ossification markers when differentiated in the presence of BMP4 and TGFβ3, choroid plexus markers in the presence of BMP4 alone, and leptomeningeal markers when differentiated in SCF without TGFβ3. The clones E69 and T42 may represent a scalable source of primitive cranial neural crest cells useful in the study of cranial embryology, and potentially cell-based therapy.

Induction of murine embryonic stem cell differentiation by medicinal plant extracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reynertson, Kurt A.; Department of Pharmacology, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065; Charlson, Mary E.

Epidemiological evidence indicates that diets high in fruits and vegetables provide a measure of cancer chemoprevention due to phytochemical constituents. Natural products are a rich source of cancer chemotherapy drugs, and primarily target rapidly cycling tumor cells. Increasing evidence indicates that many cancers contain small populations of resistant, stem-like cells that have the capacity to regenerate tumors following chemotherapy and radiation, and have been linked to the initiation of metastases. Our goal is to discover natural product-based clinical or dietary interventions that selectively target cancer stem cells, inducing differentiation. We adapted an alkaline phosphatase (AP) stain to assay plant extractsmore » for the capacity to induce differentiation in embryonic stem (ES) cells. AP is a characteristic marker of undifferentiated ES cells, and this represents a novel approach to screening medicinal plant extracts. Following a survey of approximately 100 fractions obtained from 12 species of ethnomedically utilized plants, we found fractions from 3 species that induced differentiation, decreasing AP and transcript levels of pluripotency markers (Nanog, Oct-4, Rex-1). These fractions affected proliferation of murine ES, and human embryonal, prostate, and breast carcinoma cells in a dose-dependent manner. Several phytochemical constituents were isolated; the antioxidant phytochemicals ellagic acid and gallic acid were shown to affect viability of cultured breast carcinoma cells.« less

Induction of murine embryonic stem cell differentiation by medicinal plant extracts

PubMed Central

Reynertson, Kurt A.; Charlson, Mary E.; Gudas, Lorraine J.

2010-01-01

Epidemiological evidence indicates that diets high in fruits and vegetables provide a measure of cancer chemoprevention due to phytochemical constituents. Natural products are a rich source of cancer chemotherapy drugs, and primarily target rapidly-cycling tumor cells. Increasing evidence indicates that many cancers contain small populations of resistant, stem-like cells that have the capacity to regenerate tumors following chemotherapy and radiation, and have been linked to the initiation of metastases. Our goal is to discover natural product-based clinical or dietary interventions that selectively target cancer stem cells, inducing differentiation. We adapted an alkaline phosphatase (AP) stain to assay plant extracts for the capacity to induce differentiation in embryonic stem (ES) cells. AP is a characteristic marker of undifferentiated ES cells, and this represents a novel approach to screening medicinal plant extracts. Following a survey of approximately 100 fractions obtained from twelve species of ethnomedically utilized plants, we found fractions from three species that induced differentiation, decreasing AP and transcript levels of pluripotency markers (Nanog, Oct-4, Rex-1). These fractions affected proliferation of murine ES, and human embryonal, prostate, and breast carcinoma cells in a dose-dependent manner. Several phytochemical constituents were isolated; the antioxidant phytochemicals ellagic acid and gallic acid were shown to affect viability of cultured breast carcinoma cells. PMID:20955699

Development of a Xeno-Free Feeder-Layer System from Human Umbilical Cord Mesenchymal Stem Cells for Prolonged Expansion of Human Induced Pluripotent Stem Cells in Culture

PubMed Central

Zou, Qing; Wu, Mingjun; Zhong, Liwu; Fan, Zhaoxin; Zhang, Bo; Chen, Qiang; Ma, Feng

2016-01-01

Various feeder layers have been extensively applied to support the prolonged growth of human pluripotent stem cells (hPSCs) for in vitro cultures. Among them, mouse embryonic fibroblast (MEF) and mouse fibroblast cell line (SNL) are most commonly used feeder cells for hPSCs culture. However, these feeder layers from animal usually cause immunogenic contaminations, which compromises the potential of hPSCs in clinical applications. In the present study, we tested human umbilical cord mesenchymal stem cells (hUC-MSCs) as a potent xeno-free feeder system for maintaining human induced pluripotent stem cells (hiPSCs). The hUC-MSCs showed characteristics of MSCs in xeno-free culture condition. On the mitomycin-treated hUC-MSCs feeder, hiPSCs maintained the features of undifferentiated human embryonic stem cells (hESCs), such as low efficiency of spontaneous differentiation, stable expression of stemness markers, maintenance of normal karyotypes, in vitro pluripotency and in vivo ability to form teratomas, even after a prolonged culture of more than 30 passages. Our study indicates that the xeno-free culture system may be a good candidate for growth and expansion of hiPSCs as the stepping stone for stem cell research to further develop better and safer stem cells. PMID:26882313

Development of a Xeno-Free Feeder-Layer System from Human Umbilical Cord Mesenchymal Stem Cells for Prolonged Expansion of Human Induced Pluripotent Stem Cells in Culture.

PubMed

Zou, Qing; Wu, Mingjun; Zhong, Liwu; Fan, Zhaoxin; Zhang, Bo; Chen, Qiang; Ma, Feng

2016-01-01

Various feeder layers have been extensively applied to support the prolonged growth of human pluripotent stem cells (hPSCs) for in vitro cultures. Among them, mouse embryonic fibroblast (MEF) and mouse fibroblast cell line (SNL) are most commonly used feeder cells for hPSCs culture. However, these feeder layers from animal usually cause immunogenic contaminations, which compromises the potential of hPSCs in clinical applications. In the present study, we tested human umbilical cord mesenchymal stem cells (hUC-MSCs) as a potent xeno-free feeder system for maintaining human induced pluripotent stem cells (hiPSCs). The hUC-MSCs showed characteristics of MSCs in xeno-free culture condition. On the mitomycin-treated hUC-MSCs feeder, hiPSCs maintained the features of undifferentiated human embryonic stem cells (hESCs), such as low efficiency of spontaneous differentiation, stable expression of stemness markers, maintenance of normal karyotypes, in vitro pluripotency and in vivo ability to form teratomas, even after a prolonged culture of more than 30 passages. Our study indicates that the xeno-free culture system may be a good candidate for growth and expansion of hiPSCs as the stepping stone for stem cell research to further develop better and safer stem cells.

From "ES-like" cells to induced pluripotent stem cells: a historical perspective in domestic animals.

PubMed

Koh, Sehwon; Piedrahita, Jorge A

2014-01-01

Pluripotent stem cells such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) provide great potential as cell sources for gene editing to generate genetically modified animals, as well as in the field of regenerative medicine. Stable, long-term ESCs have been established in laboratory mouse and rat; however, isolation of true pluripotent ESCs in domesticated animals such as pigs and dogs have been less successful. Initially, domesticated animal pluripotent cell lines were referred to as "embryonic stem-like" cells owing to their similar morphologic characteristics to mouse ESCs, but accompanied by a limited ability to proliferate in vitro in an undifferentiated state. That is, they shared some but not all the characteristics of true ESCs. More recently, advances in reprogramming using exogenous transcription factors, combined with the utilization of small chemical inhibitors of key biochemical pathways, have led to the isolation of iPSCs. In this review, we provide a historical perspective of the isolation of various types of pluripotent stem cells in domesticated animals. In addition, we summarize the latest progress and limitations in the derivation and application of iPSCs. Copyright © 2014 Elsevier Inc. All rights reserved.

Recurrent genomic instability of chromosome 1q in neural derivatives of human embryonic stem cells

PubMed Central

Varela, Christine; Denis, Jérôme Alexandre; Polentes, Jérôme; Feyeux, Maxime; Aubert, Sophie; Champon, Benoite; Piétu, Geneviève; Peschanski, Marc; Lefort, Nathalie

2012-01-01

Human pluripotent stem cells offer a limitless source of cells for regenerative medicine. Neural derivatives of human embryonic stem cells (hESCs) are currently being used for cell therapy in 3 clinical trials. However, hESCs are prone to genomic instability, which could limit their clinical utility. Here, we report that neural differentiation of hESCs systematically produced a neural stem cell population that could be propagated for more than 50 passages without entering senescence; this was true for all 6 hESC lines tested. The apparent spontaneous loss of evolution toward normal senescence of somatic cells was associated with a jumping translocation of chromosome 1q. This chromosomal defect has previously been associated with hematologic malignancies and pediatric brain tumors with poor clinical outcome. Neural stem cells carrying the 1q defect implanted into the brains of rats failed to integrate and expand, whereas normal cells engrafted. Our results call for additional quality controls to be implemented to ensure genomic integrity not only of undifferentiated pluripotent stem cells, but also of hESC derivatives that form cell therapy end products, particularly neural lines. PMID:22269325

The maintenance of pluripotency following laser direct-write of mouse embryonic stem cells.

PubMed

Raof, Nurazhani Abdul; Schiele, Nathan R; Xie, Yubing; Chrisey, Douglas B; Corr, David T

2011-03-01

The ability to precisely pattern embryonic stem (ES) cells in vitro into predefined arrays/geometries may allow for the recreation of a stem cell niche for better understanding of how cellular microenvironmental factors govern stem cell maintenance and differentiation. In this study, a new gelatin-based laser direct-write (LDW) technique was utilized to deposit mouse ES cells into defined arrays of spots, while maintaining stem cell pluripotency. Results obtained from these studies showed that ES cells were successfully printed into specific patterns and remained viable. Furthermore, ES cells retained the expression of Oct4 in nuclei after LDW, indicating that the laser energy did not affect their maintenance of an undifferentiated state. The differentiation potential of mouse ES cells after LDW was confirmed by their ability to form embryoid bodies (EBs) and to spontaneously become cell lineages representing all three germ layers, revealed by the expression of marker proteins of nestin (ectoderm), Myf-5 (mesoderm) and PDX-1 (endoderm), after 7 days of cultivation. Gelatin-based LDW provides a new avenue for stem cell patterning, with precision and control of the cellular microenvironment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Multipotent Stem Cell and Reproduction.

PubMed

Khanlarkhani, Neda; Baazm, Maryam; Mohammadzadeh, Farzaneh; Najafi, Atefeh; Mehdinejadiani, Shayesteh; Sobhani, Aligholi

Stem cells are self-renewing and undifferentiated cell types that can be differentiate into functional cells. Stem cells can be classified into two main types based on their source of origin: Embryonic and Adult stem cells. Stem cells also classified based on the range of differentiation potentials into Totipotent, Pluripotent, Multipotent, and Unipotent. Multipotent stem cells have the ability to differentiate into all cell types within one particular lineage. There are plentiful advantages and usages for multipotent stem cells. Multipotent Stem cells act as a significant key in procedure of development, tissue repair, and protection. The accessibility and adaptability of these amazing cells create them a great therapeutic choice for different part of medical approaches, and it becomes interesting topic in the scientific researches to found obvious method for the most advantageous use of MSC-based therapies. Recent studies in the field of stem cell biology have provided new perspectives and opportunities for the treatment of infertility disorders.

Brief report: ectopic expression of NUP98-HOXA10 augments erythroid differentiation of human embryonic stem cells.

PubMed

Ji, Junfeng; Risueño, Ruth M; Hong, Seokho; Allan, David; Rosten, Patty; Humphries, Keith; Bhatia, Mickie

2011-04-01

Hox genes encode highly conserved transcription factors that have been implicated in hematopoietic development and self-renewal of hematopoietic stem cells (HSCs) and hematopoietic development. The potency of NUP98-HOXA10hd (NA10) on adult murine bone marrow HSC self-renewal prompted us to examine its effect on specification and proliferation of hematopoietic cells derived from human embryonic stem cells (hESCs). Here, we demonstrate that expression of NA10 in hESCs influences the hematopoietic differentiation program. The specific effect of NA10 is dependent on the developmental stage of hematopoietic emergence from hESCs. Overexpression of NA10 in either undifferentiated hESCs or early hemogenic precursors augmented the frequency of CD45(-) GlycophorinA(+) cells and erythroid progenitors (blast-forming unit-erythrocyte). In contrast, targeted NA10 expression in primitive CD34+ cells committed to the hematopoietic lineage had no effect on erythropoietic capacity but instead increased hematopoietic progenitor proliferation. Our study reveals a novel neomorphic effect of NA10 in early human erythroid development from pluripotent stem cells. Copyright © 2011 AlphaMed Press.

Nuclear proteome analysis of undifferentiated mouse embryonic stem and germ cells.

PubMed

Buhr, Nicolas; Carapito, Christine; Schaeffer, Christine; Kieffer, Emmanuelle; Van Dorsselaer, Alain; Viville, Stéphane

2008-06-01

Embryonic stem cells (ESCs) and embryonic germ cells (EGCs) provide exciting models for understanding the underlying mechanisms that make a cell pluripotent. Indeed, such understanding would enable dedifferentiation and reprogrammation of any cell type from a patient needing a cell therapy treatment. Proteome analysis has emerged as an important technology for deciphering these biological processes and thereby ESC and EGC proteomes are increasingly studied. Nevertheless, their nuclear proteomes have only been poorly investigated up to now. In order to investigate signaling pathways potentially involved in pluripotency, proteomic analyses have been performed on mouse ESC and EGC nuclear proteins. Nuclei from ESCs and EGCs at undifferentiated stage were purified by subcellular fractionation. After 2-D separation, a subtractive strategy (subtracting culture environment contaminating spots) was applied and a comparison of ESC, (8.5 day post coïtum (dpc))-EGC and (11.5 dpc)-EGC specific nuclear proteomes was performed. A total of 33 ESC, 53 (8.5 dpc)-EGC, and 36 (11.5 dpc)-EGC spots were identified by MALDI-TOF-MS and/or nano-LC-MS/MS. This approach led to the identification of two isoforms (with and without N-terminal acetylation) of a known pluripotency marker, namely developmental pluripotency associated 5 (DPPA5), which has never been identified before in 2-D gel-MS studies of ESCs and EGCs. Furthermore, we demonstrated the efficiency of our subtracting strategy, in association with a nuclear subfractionation by the identification of a new protein (protein arginine N-methyltransferase 7; PRMT7) behaving as proteins involved in pluripotency.

Abrogation of E-cadherin-mediated cell-cell contact in mouse embryonic stem cells results in reversible LIF-independent self-renewal.

PubMed

Soncin, Francesca; Mohamet, Lisa; Eckardt, Dominik; Ritson, Sarah; Eastham, Angela M; Bobola, Nicoletta; Russell, Angela; Davies, Steve; Kemler, Rolf; Merry, Catherine L R; Ward, Christopher M

2009-09-01

We have previously demonstrated that differentiation of embryonic stem (ES) cells is associated with downregulation of cell surface E-cadherin. In this study, we assessed the function of E-cadherin in mouse ES cell pluripotency and differentiation. We show that inhibition of E-cadherin-mediated cell-cell contact in ES cells using gene knockout (Ecad(-/-)), RNA interference (EcadRNAi), or a transhomodimerization-inhibiting peptide (CHAVC) results in cellular proliferation and maintenance of an undifferentiated phenotype in fetal bovine serum-supplemented medium in the absence of leukemia inhibitory factor (LIF). Re-expression of E-cadherin in Ecad(-/-), EcadRNAi, and CHAVC-treated ES cells restores cellular dependence to LIF supplementation. Although reversal of the LIF-independent phenotype in Ecad(-/-) ES cells is dependent on the beta-catenin binding domain of E-cadherin, we show that beta-catenin null (betacat(-/-)) ES cells also remain undifferentiated in the absence of LIF. This suggests that LIF-independent self-renewal of Ecad(-/-) ES cells is unlikely to be via beta-catenin signaling. Exposure of Ecad(-/-), EcadRNAi, and CHAVC-treated ES cells to the activin receptor-like kinase inhibitor SB431542 led to differentiation of the cells, which could be prevented by re-expression of E-cadherin. To confirm the role of transforming growth factor beta family signaling in the self-renewal of Ecad(-/-) ES cells, we show that these cells maintain an undifferentiated phenotype when cultured in serum-free medium supplemented with Activin A and Nodal, with fibroblast growth factor 2 required for cellular proliferation. We conclude that transhomodimerization of E-cadherin protein is required for LIF-dependent ES cell self-renewal and that multiple self-renewal signaling networks subsist in ES cells, with activity dependent upon the cellular context.

Functional cooperativity between two TPA responsive elements in undifferentiated F9 embryonic stem cells.

PubMed Central

Okuda, A; Imagawa, M; Sakai, M; Muramatsu, M

1990-01-01

We have recently identified an enhancer, termed GPEI, in the 5'-flanking region of the rat glutathione transferase P gene, that is composed of two imperfect TPA (phorbol 12-O-tetradecanoate 13-acetate) responsive elements (TREs). Unlike other TRE-containing enhancers, GPEI exhibits a strong transcriptional enhancing activity in F9 embryonic stem cells. Mutational analyses have revealed that the high activity of GPEI is mediated by two imperfect TREs. Each TRE-like sequence has no activity by itself but acts synergistically to form a strong enhancer which is active even in the very low level of AP-1 activity in F9 cells. Furthermore, we show that synthetic DNAs containing two perfect TREs in certain arrangements have strong transcriptional enhancing activities in F9 cells and the activity is greatly influenced by the relative orientation and the distance of two TREs. Images Fig. 1. Fig. 2. Fig. 3. PMID:2323334

Histone h1 depletion impairs embryonic stem cell differentiation.

PubMed

Zhang, Yunzhe; Cooke, Marissa; Panjwani, Shiraj; Cao, Kaixiang; Krauth, Beth; Ho, Po-Yi; Medrzycki, Magdalena; Berhe, Dawit T; Pan, Chenyi; McDevitt, Todd C; Fan, Yuhong

2012-01-01

Pluripotent embryonic stem cells (ESCs) are known to possess a relatively open chromatin structure; yet, despite efforts to characterize the chromatin signatures of ESCs, the role of chromatin compaction in stem cell fate and function remains elusive. Linker histone H1 is important for higher-order chromatin folding and is essential for mammalian embryogenesis. To investigate the role of H1 and chromatin compaction in stem cell pluripotency and differentiation, we examine the differentiation of embryonic stem cells that are depleted of multiple H1 subtypes. H1c/H1d/H1e triple null ESCs are more resistant to spontaneous differentiation in adherent monolayer culture upon removal of leukemia inhibitory factor. Similarly, the majority of the triple-H1 null embryoid bodies (EBs) lack morphological structures representing the three germ layers and retain gene expression signatures characteristic of undifferentiated ESCs. Furthermore, upon neural differentiation of EBs, triple-H1 null cell cultures are deficient in neurite outgrowth and lack efficient activation of neural markers. Finally, we discover that triple-H1 null embryos and EBs fail to fully repress the expression of the pluripotency genes in comparison with wild-type controls and that H1 depletion impairs DNA methylation and changes of histone marks at promoter regions necessary for efficiently silencing pluripotency gene Oct4 during stem cell differentiation and embryogenesis. In summary, we demonstrate that H1 plays a critical role in pluripotent stem cell differentiation, and our results suggest that H1 and chromatin compaction may mediate pluripotent stem cell differentiation through epigenetic repression of the pluripotency genes.

1,5-Disubstituted benzimidazoles that direct cardiomyocyte differentiation from mouse embryonic stem cells.

PubMed

Okolotowicz, Karl J; Bushway, Paul; Lanier, Marion; Gilley, Cynthia; Mercola, Mark; Cashman, John R

2015-09-01

Cardiomyopathy is the leading cause of death worldwide. Despite progress in medical treatments, heart transplantation is one of the only current options for those with infarcted heart muscle. Stem cell differentiation technology may afford cell-based therapeutics that may lead to the generation of new, healthy heart muscle cells from undifferentiated stem cells. Our approach is to use small molecules to stimulate stem cell differentiation. Herein, we describe a novel class of 1,5-disubstituted benzimidazoles that induce differentiation of stem cells into cardiac cells. We report on the evaluation in vitro for cardiomyocyte differentiation and describe structure-activity relationship results that led to molecules with drug-like properties. The results of this study show the promise of small molecules to direct stem cell lineage commitment, to probe signaling pathways and to develop compounds for the stimulation of stem cells to repair damaged heart tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

1,5-Disubstituted benzimidazoles that direct cardiomyocyte differentiation from mouse embryonic stem cells

PubMed Central

Okolotowicz, Karl J.; Bushway, Paul; Lanier, Marion; Gilley, Cynthia; Cynthia, Mark; Cashman, John R.

2016-01-01

Cardiomyopathy is the leading cause of death worldwide. Despite progress in medical treatments, heart transplantation is one of the only current options for those with infarcted heart muscle. Stem cell differentiation technology may afford cell-based therapeutics that may lead to the generation of new, healthy heart muscle cells from undifferentiated stem cells. Our approach is to use small molecules to stimulate stem cell differentiation. Herein, we describe a novel class of 1,5-disubstituted benzimidazoles that induce differentiation of stem cells into cardiac cells. We report on the evaluation in vitro for cardiomyocyte differentiation and describe structure–activity relationship results that led to molecules with drug-like properties. The results of this study show the promise of small molecules to direct stem cell lineage commitment, to probe signaling pathways and to develop compounds for the stimulation of stem cells to repair damaged heart tissue. PMID:26278027

Antibody engineering of a cytotoxic monoclonal antibody 84 against human embryonic stem cells: Investigating the effects of multivalency on cytotoxicity.

PubMed

Klement, Maximilian; Zheng, Jiyun; Liu, Chengcheng; Tan, Heng-Liang; Wong, Victor Vai Tak; Choo, Andre Boon-Hwa; Lee, Dong-Yup; Ow, Dave Siak-Wei

2017-02-10

Antibody fragments have shown targeted specificity to their antigens, but only modest tissue retention times in vivo and in vitro. Multimerization has been used as a protein engineering tool to increase the number of binding units and thereby enhance the efficacy and retention time of antibody fragments. In this work, we explored the effects of valency using a series of self-assembling polypeptides based on the GCN4 leucine zipper multimerization domain fused to a single-chain variable fragment via an antibody upper hinge sequence. Four engineered antibody fragments with a valency from one to four antigen-binding units of a cytotoxic monoclonal antibody 84 against human embryonic stem cells (hESC) were constructed. We hypothesized that higher cytotoxicity would be observed for fragments with increased valency. Flow cytometry analysis revealed that the trimeric and tetrameric engineered antibody fragments resulted in the highest degree of cytotoxicity to the undifferentiated hESC, while the engineered antibody fragments were observed to have improved tissue penetration into cell clusters. Thus, a trade off was made for the trimeric versus tetrameric fragment due to improved tissue penetration. These results have direct implications for antibody-mediated removal of undifferentiated hESC during regenerative medicine and cell therapy. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

Protein tyrosine phosphatase 1B (PTP1B) is required for cardiac lineage differentiation of mouse embryonic stem cells.

PubMed

Eshkiki, Zahra Shokati; Ghahremani, Mohammad Hossein; Shabani, Parisa; Firuzjaee, Sattar Gorgani; Sadeghi, Asie; Ghanbarian, Hossein; Meshkani, Reza

2017-01-01

Protein tyrosine phosphatase 1B (PTP1B) has been shown to regulate multiple cellular events such as differentiation, cell growth, and proliferation; however, the role of PTP1B in differentiation of embryonic stem (ES) cells into cardiomyocytes remains unexplored. In the present study, we investigated the effects of PTP1B inhibition on differentiation of ES cells into cardiomyocytes. PTP1B mRNA and protein levels were increased during the differentiation of ES cells into cardiomyocytes. Accordingly, a stable ES cell line expressing PTP1B shRNA was established. In vitro, the number and size of spontaneously beating embryoid bodies were significantly decreased in PTP1B-knockdown cells, compared with the control cells. Decreased expression of cardiac-specific markers Nkx2-5, MHC-α, cTnT, and CX43, as assessed by real-time PCR analysis, was further confirmed by immunocytochemistry of the markers. The results also showed that PTP1B inhibition induced apoptosis in both differentiated and undifferentiated ES cells, as presented by increasing the level of cleaved caspase-3, cytochrome C, and cleaved PARP. Further analyses revealed that PTP1B inhibition did not change proliferation and pluripotency of undifferentiated ES cells. Taken together, the data presented here suggest that PTP1B is essential for proper differentiation of ES cells into cardiomyocytes.

Selective In Vitro Propagation of Nephron Progenitors Derived from Embryos and Pluripotent Stem Cells.

PubMed

Tanigawa, Shunsuke; Taguchi, Atsuhiro; Sharma, Nirmala; Perantoni, Alan O; Nishinakamura, Ryuichi

2016-04-26

Nephron progenitors in the embryonic kidney propagate while generating differentiated nephrons. However, in mice, the progenitors terminally differentiate shortly after birth. Here, we report a method for selectively expanding nephron progenitors in vitro in an undifferentiated state. Combinatorial and concentration-dependent stimulation with LIF, FGF2/9, BMP7, and a WNT agonist is critical for expansion. The purified progenitors proliferated beyond the physiological limits observed in vivo, both for cell numbers and lifespan. Neonatal progenitors were maintained for a week, while progenitors from embryonic day 11.5 expanded 1,800-fold for nearly 20 days and still reconstituted 3D nephrons containing glomeruli and renal tubules. Furthermore, progenitors generated from mouse embryonic stem cells and human induced pluripotent cells could be expanded with retained nephron-forming potential. Thus, we have established in vitro conditions for promoting the propagation of nephron progenitors, which will be essential for dissecting the mechanisms of kidney organogenesis and for regenerative medicine. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Cell-Type-Specific Predictive Network Yields Novel Insights into Mouse Embryonic Stem Cell Self-Renewal and Cell Fate

PubMed Central

Dowell, Karen G.; Simons, Allen K.; Wang, Zack Z.; Yun, Kyuson; Hibbs, Matthew A.

2013-01-01

Self-renewal, the ability of a stem cell to divide repeatedly while maintaining an undifferentiated state, is a defining characteristic of all stem cells. Here, we clarify the molecular foundations of mouse embryonic stem cell (mESC) self-renewal by applying a proven Bayesian network machine learning approach to integrate high-throughput data for protein function discovery. By focusing on a single stem-cell system, at a specific developmental stage, within the context of well-defined biological processes known to be active in that cell type, we produce a consensus predictive network that reflects biological reality more closely than those made by prior efforts using more generalized, context-independent methods. In addition, we show how machine learning efforts may be misled if the tissue specific role of mammalian proteins is not defined in the training set and circumscribed in the evidential data. For this study, we assembled an extensive compendium of mESC data: ∼2.2 million data points, collected from 60 different studies, under 992 conditions. We then integrated these data into a consensus mESC functional relationship network focused on biological processes associated with embryonic stem cell self-renewal and cell fate determination. Computational evaluations, literature validation, and analyses of predicted functional linkages show that our results are highly accurate and biologically relevant. Our mESC network predicts many novel players involved in self-renewal and serves as the foundation for future pluripotent stem cell studies. This network can be used by stem cell researchers (at http://StemSight.org) to explore hypotheses about gene function in the context of self-renewal and to prioritize genes of interest for experimental validation. PMID:23468881

Stem cells and cellular therapy: potential treatment for cardiovascular diseases.

PubMed

Zavos, Panayiotis M

2006-02-08

This paper reviews the current status of cloning and stem cell research and its application to treating various diseases, particularly cardiovascular disease. Recently new techniques have been developed to isolate embryonic stem cells from preimplantation embryos. These cells are undifferentiated and are therefore able to develop into the cells of whichever organ it is in contact with. These cells would be especially beneficial for the treatment of ischemia and various other cardiovascular diseases. There are a variety of various issues that need to be discussed before this technology can be applied safely, including government regulations to ensure the clinical safety and effectiveness of the procedures, as well as the prevention of improper handling or the use of contaminated tissues.

Human embryonic stem cells express a unique set of microRNAs.

PubMed

Suh, Mi-Ra; Lee, Yoontae; Kim, Jung Yeon; Kim, Soo-Kyoung; Moon, Sung-Hwan; Lee, Ji Yeon; Cha, Kwang-Yul; Chung, Hyung Min; Yoon, Hyun Soo; Moon, Shin Yong; Kim, V Narry; Kim, Kye-Seong

2004-06-15

Human embryonic stem (hES) cells are pluripotent cell lines established from the explanted inner cell mass of human blastocysts. Despite their importance for human embryology and regenerative medicine, studies on hES cells, unlike those on mouse ES (mES) cells, have been hampered by difficulties in culture and by scant knowledge concerning the regulatory mechanism. Recent evidence from plants and animals indicates small RNAs of approximately 22 nucleotides (nt), collectively named microRNAs, play important roles in developmental regulation. Here we describe 36 miRNAs (from 32 stem-loops) identified by cDNA cloning in hES cells. Importantly, most of the newly cloned miRNAs are specifically expressed in hES cells and downregulated during development into embryoid bodies (EBs), while miRNAs previously reported from other human cell types are poorly expressed in hES cells. We further show that some of the ES-specific miRNA genes are highly related to each other, organized as clusters, and transcribed as polycistronic primary transcripts. These miRNA gene families have murine homologues that have similar genomic organizations and expression patterns, suggesting that they may operate key regulatory networks conserved in mammalian pluripotent stem cells. The newly identified hES-specific miRNAs may also serve as molecular markers for the early embryonic stage and for undifferentiated hES cells.

Induction of murine embryonic stem cell differentiation by medicinal plant extracts.

PubMed

Reynertson, Kurt A; Charlson, Mary E; Gudas, Lorraine J

2011-01-01

Epidemiological evidence indicates that diets high in fruits and vegetables provide a measure of cancer chemoprevention due to phytochemical constituents. Natural products are a rich source of cancer chemotherapy drugs, and primarily target rapidly cycling tumor cells. Increasing evidence indicates that many cancers contain small populations of resistant, stem-like cells that have the capacity to regenerate tumors following chemotherapy and radiation, and have been linked to the initiation of metastases. Our goal is to discover natural product-based clinical or dietary interventions that selectively target cancer stem cells, inducing differentiation. We adapted an alkaline phosphatase (AP) stain to assay plant extracts for the capacity to induce differentiation in embryonic stem (ES) cells. AP is a characteristic marker of undifferentiated ES cells, and this represents a novel approach to screening medicinal plant extracts. Following a survey of approximately 100 fractions obtained from 12 species of ethnomedically utilized plants, we found fractions from 3 species that induced differentiation, decreasing AP and transcript levels of pluripotency markers (Nanog, Oct-4, Rex-1). These fractions affected proliferation of murine ES, and human embryonal, prostate, and breast carcinoma cells in a dose-dependent manner. Several phytochemical constituents were isolated; the antioxidant phytochemicals ellagic acid and gallic acid were shown to affect viability of cultured breast carcinoma cells. Copyright © 2010 Elsevier Inc. All rights reserved.

Isolation and culture of rabbit embryonic stem cells.

PubMed

Honda, Arata

2013-01-01

Mammalian stem cells are invaluable research resources for the study of cell and embryonic development as well as practical tools for use in the production of genetically engineered animals and further therapeutics. It is important that we further our knowledge and understanding of a variety of stem cells from several different animal species before trials in humans commence. Here we describe methods for establishing rabbit embryonic stem (rES) cell lines with indefinite proliferation potential. rES cells attain maximum proliferation potential when cultured at a feeder cell density of one-sixth of that of full confluency. Higher and lower densities of feeder cells induced ES cell differentiation or division arrest. Fibroblast growth factor (FGF)2 can maintain the undifferentiated status of rES cells; however leukemia inhibitory factor (LIF) is dispensable. Under optimized conditions, rES cells could be passaged by trypsinization 50 times. This culture system enabled efficient gene transduction and clonal expansion from single cells. rES cells grew as flat monolayer cell colonies, as reported for monkey and human ES cells, and expressed pluripotency markers. Embryoid bodies and teratomas formed readily in vitro and in vivo, respectively. Characterization of ES cells from different species is important for establishing common features of pluripotency. We have demonstrated the similarity of ES cells between rabbit and humans. These cell lines could be applied directly using gene-targeting techniques, or in combination with induced pluripotent stem cells. Thus, rES cells are a suitable model for studying human transplantation therapy and disease treatments.

[Therapeutic cloning: far from application at this stage].

PubMed

De Both, N J

2001-11-03

Therapeutic cloning has become possible since the discovery that nuclei from somatic cells of adult animal tissue can successfully be used for cloning and the fact that human embryonic stem cell lines have been established from preimplantation embryos. When nuclei from healthy tissue of a patient are transplanted into enucleated oocytes, these oocytes can be artificially activated so that embryos develop from which embryonic stem cells of the donor can be derived. These embryonic stem cells can be cultured as permanent lines in unlimited numbers and remain pluripotent, i.e. they can be induced to differentiate into the required cell type by adding one or more specific factors. These cells can then be transplanted back into the patient suffering from either a lack or dysfunction of these cells. This approach prevents the rejection of the transplanted cells by the patient's immunological system. As this type of cloning has a very low efficiency, a large number of unfertilized donor oocytes is required. It is questionable whether enough donors are or will be available for this purpose. The cultured cells must satisfy certain conditions before they can be used for transplantation. They must be checked for chromosomal abnormalities, and a complete differentiation of the embryonic stem cells into the cells types needed by the patient is necessary as after the transplantation, undifferentiated stem cells will form teratomas. Furthermore, it is difficult to ensure that the cells end up in the right place and to ensure that they fully integrate into the existing tissue to form functional connections. Due to this array of technical problems the question remains as to whether therapeutic cloning will become feasible in the near future.

Brief Report: External Beam Radiation Therapy for the Treatment of Human Pluripotent Stem Cell-Derived Teratomas.

PubMed

Lee, Andrew S; Tang, Chad; Hong, Wan Xing; Park, Sujin; Bazalova-Carter, Magdalena; Nelson, Geoff; Sanchez-Freire, Veronica; Bakerman, Isaac; Zhang, Wendy; Neofytou, Evgenios; Connolly, Andrew J; Chan, Charles K; Graves, Edward E; Weissman, Irving L; Nguyen, Patricia K; Wu, Joseph C

2017-08-01

Human pluripotent stem cells, including human embryonic stem cells (hESCs) and human induced PSCs (hiPSCs), have great potential as an unlimited donor source for cell-based therapeutics. The risk of teratoma formation from residual undifferentiated cells, however, remains a critical barrier to the clinical application of these cells. Herein, we describe external beam radiation therapy (EBRT) as an attractive option for the treatment of this iatrogenic growth. We present evidence that EBRT is effective in arresting growth of hESC-derived teratomas in vivo at day 28 post-implantation by using a microCT irradiator capable of targeted treatment in small animals. Within several days of irradiation, teratomas derived from injection of undifferentiated hESCs and hiPSCs demonstrated complete growth arrest lasting several months. In addition, EBRT reduced reseeding potential of teratoma cells during serial transplantation experiments, requiring irradiated teratomas to be seeded at 1 × 10 3 higher doses to form new teratomas. We demonstrate that irradiation induces teratoma cell apoptosis, senescence, and growth arrest, similar to established radiobiology mechanisms. Taken together, these results provide proof of concept for the use of EBRT in the treatment of existing teratomas and highlight a strategy to increase the safety of stem cell-based therapies. Stem Cells 2017;35:1994-2000. © 2017 AlphaMed Press.

Vitrification of mouse embryo-derived ICM cells: a tool for preserving embryonic stem cell potential?

PubMed

Desai, Nina; Xu, Jing; Tsulaia, Tamara; Szeptycki-Lawson, Julia; AbdelHafez, Faten; Goldfarb, James; Falcone, Tommaso

2011-02-01

Vitrification technology presents new opportunities for preservation of embryo derived stem cells without first establishing a viable ESC line. This study tests the feasibility of cryopreserving ICM cells using vitrification. ICMs from mouse embryos were isolated and vitrified in HSV straws or on cryoloops. Upon warming, the vitrified ICMs were cultured and observed for attachment and morphology. Colonies were passaged every 3-6 days. ICMs and ICM-derived ESC colonies were tested for expression of stem cell specific markers. ICMs vitrified on both the cryoloop and the HSV straw had high survival rates. ICM derived ESCs remained undifferentiated for several passages and demonstrated expression of typical stem cell markers; SSEA-1, Sox-2, Oct 4 and alkaline phosphatase. This is the first report on successful vitrification of isolated ICMs and the subsequent derivation of ESC colonies. Vitrification of isolated ICMs is a novel approach for preservation of the "stem cell source" material.

Optical Spectroscopy for Noninvasive Monitoring of Stem Cell Differentiation

PubMed Central

Downes, Andrew; Mouras, Rabah; Elfick, Alistair

2010-01-01

There is a requirement for a noninvasive technique to monitor stem cell differentiation. Several candidates based on optical spectroscopy are discussed in this review: Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and coherent anti-Stokes Raman scattering (CARS) microscopy. These techniques are briefly described, and the ability of each to distinguish undifferentiated from differentiated cells is discussed. FTIR spectroscopy has demonstrated its ability to distinguish between stem cells and their derivatives. Raman spectroscopy shows a clear reduction in DNA and RNA concentrations during embryonic stem cell differentiation (agreeing with the well-known reduction in the nucleus to cytoplasm ratio) and also shows clear increases in mineral content during differentiation of mesenchymal stem cells. CARS microscopy can map these DNA, RNA, and mineral concentrations at high speed, and Mutliplex CARS spectroscopy/microscopy is highlighted as the technique with most promise for future applications. PMID:20182537

Embryonal tumors with abundant neuropil and true rosettes: 2 illustrative cases and a review of the literature.

PubMed

Manjila, Sunil; Ray, Abhishek; Hu, Yin; Cai, Dan X; Cohen, Mark L; Cohen, Alan R

2011-01-01

Embryonal tumor with abundant neuropil and true rosettes (ETANTR) is a recently identified variant of primitive neuroectodermal tumor, with fewer than 50 cases reported in the literature to date. Histologically, this tumor has features of ependymoblastoma and neuroblastoma, demonstrating areas of fine fibrillary neuropil intermingled with ependymoblastic rosettes and zones of undifferentiated neuroepithelial cells. However, ETANTR is distinguished pathologically from other embryonal tumors by the striking abundance of neuropil. Clinically, ETANTRs have shown high malignant potential and poor clinical outcome despite aggressive treatment. The authors describe 2 illustrative surgical cases of ETANTR, one involving the longest reported survival in the literature to date. The other had a poor outcome despite high-dose adjuvant chemotherapy with sequential autologous hematopoietic stem cell rescue. The authors review the natural history and treatment strategies available for this unusual malignant pediatric brain tumor.

Effect of GSK-3 inhibitor on the proliferation of multipotent male germ line stem cells (mGSCs) derived from goat testis.

PubMed

Zhu, H; Liu, C; Sun, J; Li, M; Hua, J

2012-06-01

The glycogen synthase kinase 3 (GSK3) inhibitor, 6-bromoindirubin-3'-oxime (BIO), is a key regulator of many signaling pathways to maintain pluripotency of human and mouse embryonic stem cells (ESCs). However, the effect of BIO on derivation of dairy goat male germline stem cells (mGSCs) remains unclear. The objectives of this study were to investigate whether BIO influences derivation of dairy goat mGSCs. Dairy goat mGSCs were cultured in mTeSR containing BIO medium and its effects on the proliferation ability of goat mGSCs (derived from goats ≤2 mo of age) were evaluated by 5-Bromo-2-deoxyuridine (BrdU) incorporation and alkaline phosphatase (AP) staining. Furthermore, its effects on maintenance of the undifferentiated state of mGSCs in late passages of cultures, as well as the capacity of mGSCs to differentiate into embryoid bodies (EBs) were examined. The presence of BIO increased the mitosis index and the number of AP positive colonies, as well as expression of pluripotent markers, Oct4, Nanog, Sox2, C-myc, Klf4, E-cadherin, and the proliferative markers, Pcna and C-myc. In contrast, there was no significant change in expression of apoptosis markers, P53, P21 and cyclin-related genes (Cyclin A, CDK2, Cyclin D1), as determined by RT-PCR analysis. When mGSCs were cultured in mTeSR medium containing BIO, EBs were formed, which were capable of further differentiating into various cell types found in the three embryonic germ layers, as determined by immunofluorescence and/or histologic staining. In conclusion, adding BIO to cultures BIO significantly promoted establishment of goat mGSC colonies and maintained their undifferentiated state. Copyright © 2012 Elsevier Inc. All rights reserved.

The Plasminogen Activation System Modulates Differently Adipogenesis and Myogenesis of Embryonic Stem Cells

PubMed Central

Hadadeh, Ola; Barruet, Emilie; Peiretti, Franck; Verdier, Monique; Bernot, Denis; Hadjal, Yasmine; Yazidi, Claire El; Robaglia-Schlupp, Andrée; De Paula, Andre Maues; Nègre, Didier; Iacovino, Michelina; Kyba, Michael; Alessi, Marie-Christine; Binétruy, Bernard

2012-01-01

Regulation of the extracellular matrix (ECM) plays an important functional role either in physiological or pathological conditions. The plasminogen activation (PA) system, comprising the uPA and tPA proteases and their inhibitor PAI-1, is one of the main suppliers of extracellular proteolytic activity contributing to tissue remodeling. Although its function in development is well documented, its precise role in mouse embryonic stem cell (ESC) differentiation in vitro is unknown. We found that the PA system components are expressed at very low levels in undifferentiated ESCs and that upon differentiation uPA activity is detected mainly transiently, whereas tPA activity and PAI-1 protein are maximum in well differentiated cells. Adipocyte formation by ESCs is inhibited by amiloride treatment, a specific uPA inhibitor. Likewise, ESCs expressing ectopic PAI-1 under the control of an inducible expression system display reduced adipogenic capacities after induction of the gene. Furthermore, the adipogenic differentiation capacities of PAI-1−/− induced pluripotent stem cells (iPSCs) are augmented as compared to wt iPSCs. Our results demonstrate that the control of ESC adipogenesis by the PA system correspond to different successive steps from undifferentiated to well differentiated ESCs. Similarly, skeletal myogenesis is decreased by uPA inhibition or PAI-1 overexpression during the terminal step of differentiation. However, interfering with uPA during days 0 to 3 of the differentiation process augments ESC myotube formation. Neither neurogenesis, cardiomyogenesis, endothelial cell nor smooth muscle formation are affected by amiloride or PAI-1 induction. Our results show that the PA system is capable to specifically modulate adipogenesis and skeletal myogenesis of ESCs by successive different molecular mechanisms. PMID:23145071

Elasticity of human embryonic stem cells as determined by atomic force microscopy.

PubMed

Kiss, Robert; Bock, Henry; Pells, Steve; Canetta, Elisabetta; Adya, Ashok K; Moore, Andrew J; De Sousa, Paul; Willoughby, Nicholas A

2011-10-01

The expansive growth and differentiation potential of human embryonic stem cells (hESCs) make them a promising source of cells for regenerative medicine. However, this promise is off set by the propensity for spontaneous or uncontrolled differentiation to result in heterogeneous cell populations. Cell elasticity has recently been shown to characterize particular cell phenotypes, with undifferentiated and differentiated cells sometimes showing significant differences in their elasticities. In this study, we determined the Young's modulus of hESCs by atomic force microscopy using a pyramidal tip. Using this method we are able to take point measurements of elasticity at multiple locations on a single cell, allowing local variations due to cell structure to be identified. We found considerable differences in the elasticity of the analyzed hESCs, reflected by a broad range of Young's modulus (0.05-10 kPa). This surprisingly high variation suggests that elasticity could serve as the basis of a simple and efficient large scale purification/separation technique to discriminate subpopulations of hESCs.

KEEPING AN EYE ON RETINOBLASTOMA CONTROL OF HUMAN EMBRYONIC STEM CELLS

PubMed Central

Conklin, Jamie F.; Sage, Julien

2010-01-01

Human embryonic stem cells (hESCs) hold great promise in regenerative medicine. However, before the full potential of these cells is achieved, major basic biological questions need to be addressed. In particular, there are still gaps in our knowledge of the molecular mechanisms underlying the derivation of hESCs from blastocysts, the regulation of the undifferentiated, pluripotent state, and the control of differentiation into specific lineages. Furthermore, we still do not fully understand the tumorigenic potential of hESCs, limiting their use in regenerative medicine. The RB pathway is a key signaling module that controls cellular proliferation, cell survival, chromatin structure, and cellular differentiation in mammalian cells. Members of the RB pathway are important regulators of hESC biology and manipulation of the activity of this pathway may provide novel means to control the fate of hESCs. Here we review what is known about the expression and function of members of the RB pathway in hESCs and discuss areas of interest in this field. PMID:19760644

Non-canonical TAF complexes regulate active promoters in human embryonic stem cells.

PubMed

Maston, Glenn A; Zhu, Lihua Julie; Chamberlain, Lynn; Lin, Ling; Fang, Minggang; Green, Michael R

2012-11-13

The general transcription factor TFIID comprises the TATA-box-binding protein (TBP) and approximately 14 TBP-associated factors (TAFs). Here we find, unexpectedly, that undifferentiated human embryonic stem cells (hESCs) contain only six TAFs (TAFs 2, 3, 5, 6, 7 and 11), whereas following differentiation all TAFs are expressed. Directed and global chromatin immunoprecipitation analyses reveal an unprecedented promoter occupancy pattern: most active genes are bound by only TAFs 3 and 5 along with TBP, whereas the remaining active genes are bound by TBP and all six hESC TAFs. Consistent with these results, hESCs contain a previously undescribed complex comprising TAFs 2, 6, 7, 11 and TBP. Altering the composition of hESC TAFs, either by depleting TAFs that are present or ectopically expressing TAFs that are absent, results in misregulated expression of pluripotency genes and induction of differentiation. Thus, the selective expression and use of TAFs underlies the ability of hESCs to self-renew.DOI:http://dx.doi.org/10.7554/eLife.00068.001.

Uncovering the Role of Hypermethylation by CTG Expansion in Myotonic Dystrophy Type 1 Using Mutant Human Embryonic Stem Cells

PubMed Central

Yanovsky-Dagan, Shira; Avitzour, Michal; Altarescu, Gheona; Renbaum, Paul; Eldar-Geva, Talia; Schonberger, Oshrat; Mitrani-Rosenbaum, Stella; Levy-Lahad, Ephrat; Birnbaum, Ramon Y.; Gepstein, Lior; Epsztejn-Litman, Silvina; Eiges, Rachel

2015-01-01

Summary CTG repeat expansion in DMPK, the cause of myotonic dystrophy type 1 (DM1), frequently results in hypermethylation and reduced SIX5 expression. The contribution of hypermethylation to disease pathogenesis and the precise mechanism by which SIX5 expression is reduced are unknown. Using 14 different DM1-affected human embryonic stem cell (hESC) lines, we characterized a differentially methylated region (DMR) near the CTGs. This DMR undergoes hypermethylation as a function of expansion size in a way that is specific to undifferentiated cells and is associated with reduced SIX5 expression. Using functional assays, we provide evidence for regulatory activity of the DMR, which is lost by hypermethylation and may contribute to DM1 pathogenesis by causing SIX5 haplo-insufficiency. This study highlights the power of hESCs in disease modeling and describes a DMR that functions both as an exon coding sequence and as a regulatory element whose activity is epigenetically hampered by a heritable mutation. PMID:26190529

Membrane translocation of t-SNARE protein syntaxin-4 abrogates ground-state pluripotency in mouse embryonic stem cells

PubMed Central

Hagiwara-Chatani, Natsumi; Shirai, Kota; Kido, Takumi; Horigome, Tomoatsu; Yasue, Akihiro; Adachi, Naoki; Hirai, Yohei

2017-01-01

Embryonic stem (ES) and induced pluripotent stem (iPS) cells are attractive tools for regenerative medicine therapies. However, aberrant cell populations that display flattened morphology and lose ground-state pluripotency often appear spontaneously, unless glycogen synthase kinase 3β (GSK3β) and mitogen-activated protein kinase kinase (MEK1/2) are inactivated. Here, we show that membrane translocation of the t-SNARE protein syntaxin-4 possibly is involved in this phenomenon. We found that mouse ES cells cultured without GSK3β/MEK1/2 inhibitors (2i) spontaneously extrude syntaxin-4 at the cell surface and that artificial expression of cell surface syntaxin-4 induces appreciable morphological changes and mesodermal differentiation through dephosphorylation of Akt. Transcriptome analyses revealed several candidate elements responsible for this, specifically, an E-to P-cadherin switch and a marked downregulation of Zscan4 proteins, which are DNA-binding proteins essential for ES cell pluripotency. Embryonic carcinoma cell lines F9 and P19CL6, which maintain undifferentiated states independently of Zscan4 proteins, exhibited similar cellular behaviors upon stimulation with cell surface syntaxin-4. The functional ablation of E-cadherin and overexpression of P-cadherin reproduced syntaxin-4-induced cell morphology, demonstrating that the E- to P-cadherin switch executes morphological signals from cell surface syntaxin-4. Thus, spontaneous membrane translocation of syntaxin-4 emerged as a critical element for maintenance of the stem-cell niche. PMID:28057922

A single EBV-based vector for stable episomal maintenance and expression of GFP in human embryonic stem cells.

PubMed

Thyagarajan, Bhaskar; Scheyhing, Kelly; Xue, Haipeng; Fontes, Andrew; Chesnut, Jon; Rao, Mahendra; Lakshmipathy, Uma

2009-03-01

Stable expression of transgenes in stem cells has been a challenge due to the nonavailability of efficient transfection methods and the inability of transgenes to support sustained gene expression. Several methods have been reported to stably modify both embryonic and adult stem cells. These methods rely on integration of the transgene into the genome of the host cell, which could result in an expression pattern dependent on the number of integrations and the genomic locus of integration. To overcome this issue, site-specific integration methods mediated by integrase, adeno-associated virus or via homologous recombination have been used to generate stable human embryonic stem cell (hESC) lines. In this study, we describe a vector that is maintained episomally in hESCs. The vector used in this study is based on components derived from the Epstein-Barr virus, containing the Epstein-Barr virus nuclear antigen 1 expression cassette and the OriP origin of replication. The vector also expresses the drug-resistance marker gene hygromycin, which allows for selection and long-term maintenance of cells harboring the plasmid. Using this vector system, we show sustained expression of green fluorescent protein in undifferentiated hESCs and their differentiating embryoid bodies. In addition, the stable hESC clones show comparable expression with and without drug selection. Consistent with this observation, bulk-transfected adipose tissue-derived mesenchymal stem cells showed persistent marker gene expression as they differentiate into adipocytes, osteoblasts and chondroblasts. Episomal vectors offer a fast and efficient method to create hESC reporter lines, which in turn allows one to test the effect of overexpression of various genes on stem cell growth, proliferation and differentiation.

Differentiation and characteristics of the enhanced green fluorescent protein gene transgenic goat neural stem cells cultured in attached and non-attached plates.

PubMed

Zheng, Yue-Mao; Dang, Yong-Hui; Qiu, Shuang; Qi, Ying-Pei; Xu, Yong-Ping; Sai, Wu-Jia-Fu

2011-08-01

The aims of this study were (i) to determine whether NSCs (neural stem cells) could be isolated from the brain of embryonic day 98 fetal goat, (ii) to determine if these stem cells have the capability of multipotent differentiation following transfection with a reporter gene, EGFP (enhanced green fluorescent protein) and (iii) to study the characteristics of the stem cells cultured in attached and non-attached plates. NSCs were isolated from embryonic day 98 fetal goat brain, transfected with EGFP gene using lipofection, and subcultured in attached and non-attached plates respectively. The transgenic stem cells were induced to differentiate into osteogenic and endothelial cells in vitro respectively. Markers associated with undifferentiated NSCs and their differentiated cells were tested by RT-PCR (reverse transcription-PCR). The results demonstrated that stem cells could be isolated from embryonic day 98 fetal goat brain, and EGFP gene could be transfected into the cells. The transgenic NSCs were capable of self-renewal, a defining property of stem cells, and were grown as free-floating neurospheres in non-attached plates. When the neurospheres were transferred and cultured in attached plates, cells migrate from the neurospheres and are grown as spindle cells. The stem cells were grown as quasi-circular cells when the single stem cells were cultured in attached plates. Both the NSCs cultured in non-attached and attached plates could express Hes1 (hairy and enhancer of split 1), Oct4 (octamer-binding protein 4), Nanog, Sox2 [SRY (sex-determining region Y)-box 2] and Nestin, while following differentiation cells expressed markers for osteogenic cells (Osteocalcin+ and Osteonectin+) and endothelium (CD34+ and eNOS+). The results demonstrated that the goat EGFP gene transgenic NSCs have the capability of multipotent differentiation, which means that the transgenic NSCs may be useful in cell transplantation studies in future.

Three-dimensional neural differentiation of embryonic stem cells with ACM induction in microfibrous matrices in bioreactors.

PubMed

Liu, Ning; Ouyang, Anli; Li, Yan; Yang, Shang-Tian

2013-01-01

The clinical use of pluripotent stem cell (PSC)-derived neural cells requires an efficient differentiation process for mass production in a bioreactor. Toward this goal, neural differentiation of murine embryonic stem cells (ESCs) in three-dimensional (3D) polyethylene terephthalate microfibrous matrices was investigated in this study. To streamline the process and provide a platform for process integration, the neural differentiation of ESCs was induced with astrocyte-conditioned medium without the formation of embryoid bodies, starting from undifferentiated ESC aggregates expanded in a suspension bioreactor. The 3D neural differentiation was able to generate a complex neural network in the matrices. When compared to 2D differentiation, 3D differentiation in microfibrous matrices resulted in a higher percentage of nestin-positive cells (68% vs. 54%) and upregulated gene expressions of nestin, Nurr1, and tyrosine hydroxylase. High purity of neural differentiation in 3D microfibrous matrix was also demonstrated in a spinner bioreactor with 74% nestin + cells. This study demonstrated the feasibility of a scalable process based on 3D differentiation in microfibrous matrices for the production of ESC-derived neural cells. © 2013 American Institute of Chemical Engineers.

Telomeric noncoding RNA promotes mouse embryonic stem cell self-renewal through inhibition of TCF3 activity.

PubMed

Xu, Xiaojuan; Guo, Mengmeng; Zhang, Na; Ye, Shoudong

2018-06-01

Although long noncoding RNAs (lncRNAs) are emerging as new modulators in the fate decision of pluripotent stem cells, the functions of specific lncRNAs remain unclear. Here, we found that telomeric RNA (TERRA or TelRNA), one type of lncRNAs, is highly expressed in mouse embryonic stem cells (mESCs) but declines significantly upon differentiation. TERRA is induced by the Wnt/β-catenin signaling pathway and can reproduce its self-renewal-promoting effect when overexpressed. Further studies revealed that T cell factor 3 ( TCF3) is a potential downstream target of TERRA and mediates the effect of TERRA in mESC maintenance. TERRA inhibits TCF3 transcription, while enforced TCF3 expression abrogates the undifferentiated state of mESCs supported by TERRA. Accordingly, the transcripts of the pluripotency genes Esrrb, Tfcp2l1, and Klf2, repressed by TCF3 in mESCs, are increased in TERRA-overexpressing cells. Our study therefore highlights the important role of TERRA in mESC maintenance and also uncovers a mechanism by which TERRA promotes self-renewal. These data will expand our understanding of the pluripotent regulatory network of ESCs.

Production of human CD59-transgenic pigs by embryonic germ cell nuclear transfer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahn, Kwang Sung; Won, Ji Young; Park, Jin-Ki

Research highlights: {yields} Human CD59 (hCD59) gene was introduced into porcine embryonic germ (EG) cells. {yields} hCD59-transgenic EG cells were resistant to hyperacute rejection in cytolytic assay. {yields} hCD59-transgenic pigs were produced by EG cell nuclear transfer. -- Abstract: This study was performed to produce transgenic pigs expressing the human complement regulatory protein CD59 (hCD59) using the nuclear transfer (NT) of embryonic germ (EG) cells, which are undifferentiated stem cells derived from primordial germ cells. Because EG cells can be cultured indefinitely in an undifferentiated state, they may provide an inexhaustible source of nuclear donor cells for NT to producemore » transgenic pigs. A total of 1980 NT embryos derived from hCD59-transgenic EG cells were transferred to ten recipients, resulting in the birth of fifteen piglets from three pregnancies. Among these offspring, ten were alive without overt health problems. Based on PCR analysis, all fifteen piglets were confirmed as hCD59 transgenic. The expression of the hCD59 transgene in the ten living piglets was verified by RT-PCR. Western analysis showed the expression of the hCD59 protein in four of the ten RT-PCR-positive piglets. These results demonstrate that hCD59-transgenic pigs could effectively be produced by EG cell NT and that such transgenic pigs may be used as organ donors in pig-to-human xenotransplantation.« less

Epigenetic regulation of osteogenesis: human embryonic palatal mesenchymal cells.

PubMed

Barkhordarian, Andre; Sison, Jay; Cayabyab, Riana; Mahanian, Nicole; Chiappelli, Francesco

2011-01-06

Mesenchymal stem cells (MSCs) provide an appropriate model to study epigenetic changes during osteogenesis and bone regeneration due to their differentiation potential. Since there are no unique markers for MSCs, methods of identification are limited. The complex morphology of human embryonic palatal mesenchyme stem cell (HEPM) requires analysis of fractal dimensions to provide an objective quantification of self-similarity, a statistical transformation of cellular shape and border complexity. We propose the hypothesis of a study to compare and contrast sequential steps of osteogenic differentiation in HEPMs both phenotypically using immunocytochemistry, and morphometrically using fractal analysis from undifferentiated passage 1 (P1) to passage 7 (P7) cells. The proof-of-concept is provided by results we present here that identify and compare the modulation of expression of certain epigenetic biomarkers (alkaline phosphatase, ALP; stromal interaction molecule-1, STRO-1; runt-related transcription factor-2, RUNX2), which are established markers of osteogenesis in bone marrow studies, of osteoblastic/skeletal morphogenesis, and of osteoblast maturation. We show that Osteoinductive medium (OIM) modulates the rate of differentiation of HEPM into Run-2+ cells, the most differentiated subpopulation, followed by ALP+ and STRO-1+ cells. Taken together, our phenotypical and morphometric data demonstrate the feasibility of using HEPM to assess osteogenic differentiation from an early undifferentiated to a differentiated stage. This research model may lay the foundation for future studies aimed at characterizing the epigenetic characteristics of osteoimmunological disorders and dysfunctions (e.g., osteoarthritis, temporomandibular joint disorders), so that proteomic profiling can aid the diagnosis and monitor the prognosis of these and other osteoimmunopathologies.

Nuclear transfer to study the nuclear reprogramming of human stem cells.

PubMed

Saito, Shigeo; Sawai, Ken; Murayama, Yoshinobu; Fukuda, Keiichi; Yokoyama, Kazunari

2008-01-01

Research of stem cells will enable us to understand the development and function of tissues and organs in mammals. The ability to induce regeneration of new tissues from embryonic stem (ES) cells derived from cloned blastocysts via nuclear transfer can be expected in the not-too-distant future. The fact that there is no way except nuclear cloning for the return of differentiated cells to undifferentiated cells remains an interesting problem to be solved. We describe protocols for the production of cloned calves from bovine ES cells to study nuclear reprogramming ability of stem cells. The frequency of term pregnancies for blastocysts from ES cells is higher than those of early pregnancies and maintained pregnancies after nuclear transfer with bovine somatic cells. We also describe protocols for gene introduction into bovine ES cells in vitro, particularly the human leukocyte antigens (HLA). Bovine ES cells provide a powerful tool for the generation of transgenic clonal offspring. This technique, when perfected for humans, may be critical for neural stem cell transplantation.

Clonal analysis of human embryonic stem cell differentiation into teratomas.

PubMed

Blum, Barak; Benvenisty, Nissim

2007-08-01

Differentiation of human embryonic stem cells (HESCs) can be studied in vivo through the induction of teratomas in immune-deficient mice. Cells within the teratomas differentiate into all three embryonic germ layers. However, the exact nature of the proliferation and differentiation of HESCs within the teratoma is not fully characterized, and it is not clear whether the differentiation is cell autonomous or affected by neighboring cells. Here, we establish a genetic approach to study the clonality of differentiation in teratomas using a mixture of HESC lines. We first demonstrate, by means of 5-bromo-2'-deoxyuridine incorporation, that cell proliferation occurs throughout the teratoma, and that there are no clusters of undifferentiated-proliferating cells. Using a combination of laser capture microdissection and DNA fingerprinting analysis, we show that different cell lines contribute mutually to the same distinctive tissue structures. Further support for the nonclonal differentiation within the teratoma was achieved by fluorescence in situ hybridization analysis of sex chromosomes. We therefore suggest that in vivo differentiation of HESCs is polyclonal and, thus, may not be cell autonomous, stressing the need for a three-dimensional growth in order to achieve complex differentiation of HESCs. Disclosure of potential conflicts of interest is found at the end of this article.

Derivation and characterisation of the human embryonic stem cell lines, NOTT1 and NOTT2.

PubMed

Priddle, Helen; Allegrucci, Cinzia; Burridge, Paul; Munoz, Maria; Smith, Nigel M; Devlin, Lyndsey; Sjoblom, Cecilia; Chamberlain, Sarah; Watson, Sue; Young, Lorraine E; Denning, Chris

2010-04-01

The ability to maintain human embryonic stem cells (hESCs) during long-term culture and yet induce differentiation to multiple lineages potentially provides a novel approach to address various biomedical problems. Here, we describe derivation of hESC lines, NOTT1 and NOTT2, from human blastocysts graded as 3BC and 3CB, respectively. Both lines were successfully maintained as colonies by mechanical passaging on mouse embryonic feeder cells or as monolayers by trypsin-passaging in feeder-free conditions on Matrigel. Undifferentiated cells retained expression of pluripotency markers (OCT4, NANOG, SSEA-4, TRA-1-60 and TRA-1-81), a stable karyotype during long-term culture and could be transfected efficiently with plasmid DNA and short interfering RNA. Differentiation via formation of embryoid bodies resulted in expression of genes associated with early germ layers and terminal lineage specification. The electrophysiology of spontaneously beating NOTT1-derived cardiomyocytes was recorded and these cells were shown to be pharmacologically responsive. Histological examination of teratomas formed by in vivo differentiation of both lines in severe immunocompromised mice showed complex structures including cartilage or smooth muscle (mesoderm), luminal epithelium (endoderm) and neuroectoderm (ectoderm). These observations show that NOTT1 and NOTT2 display the accepted characteristics of hESC pluripotency.

Rabbit embryonic stem cell lines derived from fertilized, parthenogenetic or somatic cell nuclear transfer embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fang, Zhen F.; Gai, Hui; Huang, You Z.

2006-11-01

Embryonic stem cells were isolated from rabbit blastocysts derived from fertilization (conventional rbES cells), parthenogenesis (pES cells) and nuclear transfer (ntES cells), and propagated in a serum-free culture system. Rabbit ES (rbES) cells proliferated for a prolonged time in an undifferentiated state and maintained a normal karyotype. These cells grew in a monolayer with a high nuclear/cytoplasm ratio and contained a high level of alkaline phosphate activity. In addition, rbES cells expressed the pluripotent marker Oct-4, as well as EBAF2, FGF4, TDGF1, but not antigens recognized by antibodies against SSEA-1, SSEA-3, SSEA-4, TRA-1-10 and TRA-1-81. All 3 types of ESmore » cells formed embryoid bodies and generated teratoma that contained tissue types of all three germ layers. rbES cells exhibited a high cloning efficiency, were genetically modified readily and were used as nuclear donors to generate a viable rabbit through somatic cell nuclear transfer. In combination with genetic engineering, the ES cell technology should facilitate the creation of new rabbit lines.« less

RNAi-Dependent and Independent Control of LINE1 Accumulation and Mobility in Mouse Embryonic Stem Cells

PubMed Central

Ciaudo, Constance; Jay, Florence; Okamoto, Ikuhiro; Chen, Chong-Jian; Sarazin, Alexis; Servant, Nicolas; Barillot, Emmanuel; Heard, Edith; Voinnet, Olivier

2013-01-01

In most mouse tissues, long-interspersed elements-1 (L1s) are silenced via methylation of their 5′-untranslated regions (5′-UTR). A gradual loss-of-methylation in pre-implantation embryos coincides with L1 retrotransposition in blastocysts, generating potentially harmful mutations. Here, we show that Dicer- and Ago2-dependent RNAi restricts L1 accumulation and retrotransposition in undifferentiated mouse embryonic stem cells (mESCs), derived from blastocysts. RNAi correlates with production of Dicer-dependent 22-nt small RNAs mapping to overlapping sense/antisense transcripts produced from the L1 5′-UTR. However, RNA-surveillance pathways simultaneously degrade these transcripts and, consequently, confound the anti-L1 RNAi response. In Dicer−/− mESC complementation experiments involving ectopic Dicer expression, L1 silencing was rescued in cells in which microRNAs remained strongly depleted. Furthermore, these cells proliferated and differentiated normally, unlike their non-complemented counterparts. These results shed new light on L1 biology, uncover defensive, in addition to regulatory roles for RNAi, and raise questions on the differentiation defects of Dicer−/− mESCs. PMID:24244175

Polycomb-like 2 Associates with PRC2 and Regulates Transcriptional Networks during Mouse Embryonic Stem Cell Self-Renewal and Differentiation

PubMed Central

Walker, Emily; Chang, Wing Y.; Hunkapiller, Julie; Cagney, Gerard; Garcha, Kamal; Torchia, Joseph; Krogan, Nevan J.; Reiter, Jeremy F.; Stanford, William L.

2010-01-01

Summary Polycomb group (PcG) proteins are conserved epigenetic transcriptional repressors that control numerous developmental gene expression programs and have recently been implicated in modulating embryonic stem cell (ESC) fate. We identified the PcG protein PCL2 (polycomb-like 2) in a genome-wide screen for regulators of self-renewal and pluripotency and predicted that it would play an important role in mouse ESC fate determination. Using multiple biochemical strategies, we provide evidence that PCL2 is a Polycomb Repressive Complex 2 (PRC2)-associated protein in mouse ESCs. Knockdown of Pcl2 in ESCs resulted in heightened self-renewal characteristics, defects in differentiation and altered patterns of histone methylation. Integration of global gene expression and promoter occupancy analyses allowed us to identify PCL2 and PRC2 transcriptional targets and draft regulatory networks. We describe the role of PCL2 in both modulating transcription of ESC self-renewal genes in undifferentiated ESCs as well as developmental regulators during early commitment and differentiation. PMID:20144788

Effect of mitomycin-C on human foreskin fibroblasts used as feeders in human embryonic stem cells: immunocytochemistry MIB1 score and DNA ploidy and apoptosis evaluated by flow cytometry.

PubMed

Nieto, A; Cabrera, C M; Catalina, P; Cobo, F; Barnie, A; Cortés, J L; Barroso del Jesus, A; Montes, R; Concha, A

2007-03-01

Mitomycin C (MMC) treatment has been used to arrest cell proliferation but not much is known about the effect of MMC on human foreskin fibroblasts (HFF) used as feeders for human embryonic stem cells (hESC). We tested the ability of MMC to stop the proliferation of HFF and to induce apoptosis. MMC inhibited the proliferation of HFF at 10 microg/ml over 2.5h of MMC treatment showing a decrease in the proliferation index measured by Ki-67 and S and G2/M phases related to active HFF. A low percentage of cells showed necrotic or apoptotic features using different lengths of incubation. Over time, the majority of cells remained in a mitotically inactive state. The percentage of apoptotic cells increased from day 2 to day 10, at the same time as the necrotic ones increased. The HS181 hESC line grew in an undifferentiated state on inactive HFF throughout the study.

Non-canonical TAF complexes regulate active promoters in human embryonic stem cells

PubMed Central

Maston, Glenn A; Zhu, Lihua Julie; Chamberlain, Lynn; Lin, Ling; Fang, Minggang; Green, Michael R

2012-01-01

The general transcription factor TFIID comprises the TATA-box-binding protein (TBP) and approximately 14 TBP-associated factors (TAFs). Here we find, unexpectedly, that undifferentiated human embryonic stem cells (hESCs) contain only six TAFs (TAFs 2, 3, 5, 6, 7 and 11), whereas following differentiation all TAFs are expressed. Directed and global chromatin immunoprecipitation analyses reveal an unprecedented promoter occupancy pattern: most active genes are bound by only TAFs 3 and 5 along with TBP, whereas the remaining active genes are bound by TBP and all six hESC TAFs. Consistent with these results, hESCs contain a previously undescribed complex comprising TAFs 2, 6, 7, 11 and TBP. Altering the composition of hESC TAFs, either by depleting TAFs that are present or ectopically expressing TAFs that are absent, results in misregulated expression of pluripotency genes and induction of differentiation. Thus, the selective expression and use of TAFs underlies the ability of hESCs to self-renew. DOI: http://dx.doi.org/10.7554/eLife.00068.001 PMID:23150797

A molecular scheme for improved characterization of human embryonic stem cell lines

PubMed Central

Josephson, Richard; Sykes, Gregory; Liu, Ying; Ording, Carol; Xu, Weining; Zeng, Xianmin; Shin, Soojung; Loring, Jeanne; Maitra, Anirban; Rao, Mahendra S; Auerbach, Jonathan M

2006-01-01

Background Human embryonic stem cells (hESC) offer a renewable source of a wide range of cell types for use in research and cell-based therapies to treat disease. Inspection of protein markers provides important information about the current state of the cells and data for subsequent manipulations. However, hESC must be routinely analyzed at the genomic level to guard against deleterious changes during extensive propagation, expansion, and manipulation in vitro. Results We found that short tandem repeat (STR) analysis, human leukocyte antigen (HLA) typing, single nucleotide polymorphism (SNP) genomic analysis, mitochondrial DNA sequencing, and gene expression analysis by microarray can be used to fully describe any hESC culture in terms of its identity, stability, and undifferentiated state. Conclusion Here we describe, using molecular biology alone, a comprehensive characterization of 17 different hESC lines. The use of amplified nucleic acids means that for the first time full characterization of hESC lines can be performed with little time investment and a minimum of material. The information thus gained will facilitate comparison of lines and replication of results between laboratories. PMID:16919167

Uncovering the Role of Hypermethylation by CTG Expansion in Myotonic Dystrophy Type 1 Using Mutant Human Embryonic Stem Cells.

PubMed

Yanovsky-Dagan, Shira; Avitzour, Michal; Altarescu, Gheona; Renbaum, Paul; Eldar-Geva, Talia; Schonberger, Oshrat; Mitrani-Rosenbaum, Stella; Levy-Lahad, Ephrat; Birnbaum, Ramon Y; Gepstein, Lior; Epsztejn-Litman, Silvina; Eiges, Rachel

2015-08-11

CTG repeat expansion in DMPK, the cause of myotonic dystrophy type 1 (DM1), frequently results in hypermethylation and reduced SIX5 expression. The contribution of hypermethylation to disease pathogenesis and the precise mechanism by which SIX5 expression is reduced are unknown. Using 14 different DM1-affected human embryonic stem cell (hESC) lines, we characterized a differentially methylated region (DMR) near the CTGs. This DMR undergoes hypermethylation as a function of expansion size in a way that is specific to undifferentiated cells and is associated with reduced SIX5 expression. Using functional assays, we provide evidence for regulatory activity of the DMR, which is lost by hypermethylation and may contribute to DM1 pathogenesis by causing SIX5 haplo-insufficiency. This study highlights the power of hESCs in disease modeling and describes a DMR that functions both as an exon coding sequence and as a regulatory element whose activity is epigenetically hampered by a heritable mutation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Phase resolved and coherence gated en face reflection imaging of multilayered embryonal carcinoma cells

NASA Astrophysics Data System (ADS)

Yamauchi, Toyohiko; Fukami, Tadashi; Iwai, Hidenao; Yamashita, Yutaka

2012-03-01

Embryonal carcinoma (EC) cells, which are cell lines derived from teratocarcinomas, have characteristics in common with stem cells and differentiate into many kinds of functional cells. Similar to embryonic stem (ES) cells, undifferentiated EC cells form multi-layered spheroids. In order to visualize the three-dimensional structure of multilayered EC cells without labeling, we employed full-field interference microscopy with the aid of a low-coherence quantitative phase microscope, which is a reflection-type interference microscope employing the digital holographic technique with a low-coherent light source. Owing to the low-coherency of the light-source (halogen lamp), only the light reflected from reflective surface at a specific sectioning height generates an interference image on the CCD camera. P19CL6 EC cells, derived from mouse teratocarcinomas, formed spheroids that are about 50 to 200 micrometers in diameter. Since the height of each cell is around 10 micrometers, it is assumed that each spheroid has 5 to 20 cell layers. The P19CL6 spheroids were imaged in an upright configuration and the horizontally sectioned reflection images of the sample were obtained by sequentially and vertically scanning the zero-path-length height. Our results show the threedimensional structure of the spheroids, in which plasma and nuclear membranes were distinguishably imaged. The results imply that our technique is further capable of imaging induced pluripotent stem (iPS) cells for the assessment of cell properties including their pluripotency.

Progenitor cells for regenerative medicine and consequences of ART and cloning-associated epimutations.

PubMed

Laprise, Shari L

2010-06-01

The "holy grail" of regenerative medicine is the identification of an undifferentiated progenitor cell that is pluripotent, patient specific, and ethically unambiguous. Such a progenitor cell must also be able to differentiate into functional, transplantable tissue, while avoiding the risks of immune rejection. With reports detailing aberrant genomic imprinting associated with assisted reproductive technologies (ART) and reproductive cloning, the idea that human embryonic stem cells (hESCs) derived from surplus in vitro fertilized embryos or nuclear transfer ESCs (ntESCs) harvested from cloned embryos may harbor dangerous epigenetic errors has gained attention. Various progenitor cell sources have been proposed for human therapy, from hESCs to ntESCs, and from adult stem cells to induced pluripotent stem cells (iPS and piPS cells). This review highlights the advantages and disadvantages of each of these technologies, with particular emphasis on epigenetic stability.

Production of feline leukemia inhibitory factor with biological activity in Escherichia coli.

PubMed

Kanegi, R; Hatoya, S; Tsujimoto, Y; Takenaka, S; Nishimura, T; Wijewardana, V; Sugiura, K; Takahashi, M; Kawate, N; Tamada, H; Inaba, T

2016-07-15

Leukemia inhibitory factor (LIF) is a cytokine which is essential for oocyte and embryo development, embryonic stem cell, and induced pluripotent stem cell maintenance. Leukemia inhibitory factor improves the maturation of oocytes in the human and the mouse. However, feline LIF (fLIF) cloning and effects on oocytes during IVM have not been reported. Thus, we cloned complete cDNA of fLIF and examined its biological activity and effects on oocytes during IVM in the domestic cat. The aminoacid sequence of fLIF revealed a homology of 81% or 92% with that of mouse or human. The fLIF produced by pCold TF DNA in Escherichia coli was readily soluble and after purification showed bioactivity in maintaining the undifferentiated state of mouse embryonic stem cells and enhancing the proliferation of human erythrocyte leukemia cells. Furthermore, 10- and 100-ng/mL fLIF induced cumulus expansion with or without FSH and EGF (P < 0.05). The rate of metaphase II oocytes was also improved with 100-ng/mL fLIF (P < 0.05). We therefore confirmed the successful production for the first time of biologically active fLIF and revealed its effects on oocytes during IVM in the domestic cat. Feline LIF will further improve reproduction and stem cell research in the feline family. Copyright © 2016 Elsevier Inc. All rights reserved.

Multipotent progenitor cells are present in human peripheral blood.

PubMed

Cesselli, Daniela; Beltrami, Antonio Paolo; Rigo, Silvia; Bergamin, Natascha; D'Aurizio, Federica; Verardo, Roberto; Piazza, Silvano; Klaric, Enio; Fanin, Renato; Toffoletto, Barbara; Marzinotto, Stefania; Mariuzzi, Laura; Finato, Nicoletta; Pandolfi, Maura; Leri, Annarosa; Schneider, Claudio; Beltrami, Carlo Alberto; Anversa, Piero

2009-05-22

To determine whether the peripheral blood in humans contains a population of multipotent progenitor cells (MPCs), products of leukapheresis were obtained from healthy donor volunteers following the administration of granulocyte colony-stimulating factor. Small clusters of adherent proliferating cells were collected, and these cells continued to divide up to 40 population doublings without reaching replicative senescence and growth arrest. MPCs were positive for the transcription factors Nanog, Oct3/4, Sox2, c-Myc, and Klf4 and expressed several antigens characteristic of mesenchymal stem cells. However, they were negative for markers of hematopoietic stem/progenitor cells and bone marrow cell lineages. MPCs had a cloning efficiency of approximately 3%, and following their expansion, retained a highly immature phenotype. Under permissive culture conditions, MPCs differentiated into neurons, glial cells, hepatocytes, cardiomyocytes, endothelial cells, and osteoblasts. Moreover, the gene expression profile of MPCs partially overlapped with that of neural and embryonic stem cells, further demonstrating their primitive, uncommitted phenotype. Following subcutaneous transplantation in nonimmunosuppressed mice, MPCs migrated to distant organs and integrated structurally and functionally within the new tissue, acquiring the identity of resident parenchymal cells. In conclusion, undifferentiated cells with properties of embryonic stem cells can be isolated and expanded from human peripheral blood after granulocyte colony-stimulating factor administration. This cell pool may constitute a unique source of autologous cells with critical clinical import.

Expression and Purification of Recombinant Human Basic Fibroblast Growth Factor Fusion Proteins and Their Uses in Human Stem Cell Culture.

PubMed

Imsoonthornruksa, Sumeth; Pruksananonda, Kamthorn; Parnpai, Rangsun; Rungsiwiwut, Ruttachuk; Ketudat-Cairns, Mariena

2015-01-01

To reduce the cost of cytokines and growth factors in stem cell research, a simple method for the production of soluble and biological active human basic fibroblast growth factor (hbFGF) fusion protein in Escherichia coli was established. Under optimal conditions, approximately 60-80 mg of >95% pure hbFGF fusion proteins (Trx-6xHis-hbFGF and 6xHis-hbFGF) were obtained from 1 liter of culture broth. The purified hbFGF proteins, both with and without the fusion tags, were biologically active, which was confirmed by their ability to stimulate proliferation of NIH3T3 cells. The fusion proteins also have the ability to support several culture passages of undifferentiated human embryonic stem cells and induce pluripotent stem cells. This paper describes a low-cost and uncomplicated method for the production and purification of biologically active hbFGF fusion proteins. © 2015 S. Karger AG, Basel.

wnt3a but not wnt11 supports self-renewal of embryonic stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singla, Dinender K.; Schneider, David J.; LeWinter, Martin M.

2006-06-30

wnt proteins (wnts) promote both differentiation of midbrain dopaminergic cells and self-renewal of haematopoietic stem cells. Mouse embryonic stem (ES) cells can be maintained and self-renew on mouse feeder cell layers or in media containing leukemia inhibitory factor (LIF). However, the effects of wnts on ES cells self-renewal and differentiation are not clearly understood. In the present study, we found that conditioned medium prepared from L cells expressing wnt3a can replace feeder cell layers and medium containing LIF in maintaining ES cells in the proliferation without differentiation (self-renewal) state. By contrast, conditioned medium from NIH3T3 cells expressing wnt11 did not.more » Alkaline phosphatase staining and compact colony formation were used as criteria of cells being in the undifferentiated state. ES cells maintained in medium conditioned by Wnt3a expressing cells underwent freezing and thawing while maintaining properties seen with LIF maintained ES cells. Purified wnt3a did not maintain self-renewal of ES cells for prolonged intervals. Thus, other factors in the medium conditioned by wnt3a expressing cells may have contributed to maintenance of ES cells in a self-renewal state. Pluripotency of ES cells was determined with the use of embryoid bodies in vitro. PD98059, a MEK specific inhibitor, promoted the growth of undifferentiated ES cells maintained in conditioned medium from wnt3a expressing cells. By contrast, the P38 MAPK inhibitor SB230580 did not, suggesting a role for the MEK pathway in self-renewal and differentiation of ES cells maintained in the wnt3a cell conditioned medium. Thus, our results show that conditioned medium from wnt3a but not wnt11 expressing cells can maintain ES cells in self-renewal and in a pluripotent state.« less

WNT signaling in stem cell biology and regenerative medicine.

PubMed

Katoh, Masaru

2008-07-01

WNT family members are secreted-type glycoproteins to orchestrate embryogenesis, to maintain homeostasis, and to induce pathological conditions. FZD1, FZD2, FZD3, FZD4, FZD5, FZD6, FZD7, FZD8, FZD9, FZD10, LRP5, LRP6, and ROR2 are transmembrane receptors transducing WNT signals based on ligand-dependent preferentiality for caveolin- or clathrin-mediated endocytosis. WNT signals are transduced to canonical pathway for cell fate determination, and to non-canonical pathways for regulation of planar cell polarity, cell adhesion, and motility. MYC, CCND1, AXIN2, FGF20, WISP1, JAG1, DKK1 and Glucagon are target genes of canonical WNT signaling cascade, while CD44, Vimentin and STX5 are target genes of non-canonical WNT signaling cascades. However, target genes of WNT signaling cascades are determined in a context-dependent manner due to expression profile of transcription factors and epigenetic status. WNT signaling cascades network with Notch, FGF, BMP and Hedgehog signaling cascades to regulate the balance of stem cells and progenitor cells. Here WNT signaling in embryonic stem cells, neural stem cells, mesenchymal stem cells, hematopoietic stem cells, and intestinal stem cells will be reviewed. WNT3, WNT5A and WNT10B are expressed in undifferentiated human embryonic stem cells, while WNT6, WNT8B and WNT10B in endoderm precursor cells. Wnt6 is expressed in intestinal crypt region for stem or progenitor cells. TNF/alpha-WNT10B signaling is a negative feedback loop to maintain homeostasis of adipose tissue and gastrointestinal mucosa with chronic inflammation. Recombinant WNT protein or WNT mimetic (circular peptide, small molecule compound, or RNA aptamer) in combination with Notch mimetic, FGF protein, and BMP protein opens a new window to tissue engineering for regenerative medicine.

Survival of partially differentiated mouse embryonic stem cells in the scala media of the guinea pig cochlea.

PubMed

Hildebrand, Michael S; Dahl, Hans-Henrik M; Hardman, Jennifer; Coleman, Bryony; Shepherd, Robert K; de Silva, Michelle G

2005-12-01

The low regenerative capacity of the hair cells of the mammalian inner ear is a major obstacle for functional recovery following sensorineural hearing loss. A potential treatment is to replace damaged tissue by transplantation of stem cells. To test this approach, undifferentiated and partially differentiated mouse embryonic stem (ES) cells were delivered into the scala media of the deafened guinea pig cochlea. Transplanted cells survived in the scala media for a postoperative period of at least nine weeks, evidenced by histochemical and direct fluorescent detection of enhanced green fluorescent protein (EGFP). Transplanted cells were discovered near the spiral ligament and stria vascularis in the endolymph fluid of the scala media. In some cases, cells were observed close to the damaged organ of Corti structure. There was no evidence of significant immunological rejection of the implanted ES cells despite the absence of immunosuppression. Our surgical approach allowed efficient delivery of ES cells to the scala media while preserving the delicate structures of the cochlea. This is the first report of the survival of partially differentiated ES cells in the scala media of the mammalian cochlea, and it provides support for the potential of cell-based therapies for sensorineural hearing impairment.

Survival of Partially Differentiated Mouse Embryonic Stem Cells in the Scala Media of the Guinea Pig Cochlea

PubMed Central

Hildebrand, Michael S.; Dahl, Hans-Henrik M.; Hardman, Jennifer; Coleman, Bryony; Shepherd, Robert K.

2005-01-01

The low regenerative capacity of the hair cells of the mammalian inner ear is a major obstacle for functional recovery following sensorineural hearing loss. A potential treatment is to replace damaged tissue by transplantation of stem cells. To test this approach, undifferentiated and partially differentiated mouse embryonic stem (ES) cells were delivered into the scala media of the deafened guinea pig cochlea. Transplanted cells survived in the scala media for a postoperative period of at least nine weeks, evidenced by histochemical and direct fluorescent detection of enhanced green fluorescent protein (EGFP). Transplanted cells were discovered near the spiral ligament and stria vascularis in the endolymph fluid of the scala media. In some cases, cells were observed close to the damaged organ of Corti structure. There was no evidence of significant immunological rejection of the implanted ES cells despite the absence of immunosuppression. Our surgical approach allowed efficient delivery of ES cells to the scala media while preserving the delicate structures of the cochlea. This is the first report of the survival of partially differentiated ES cells in the scala media of the mammalian cochlea, and it provides support for the potential of cell-based therapies for sensorineural hearing impairment. PMID:16208453

Prohibitin 2 Regulates the Proliferation and Lineage-Specific Differentiation of Mouse Embryonic Stem Cells in Mitochondria

PubMed Central

Komazaki, Shinji; Enomoto, Kei; Seki, Yasuhiro; Wang, Ying Ying; Ishigaki, Yohei; Ninomiya, Naoto; Noguchi, Taka-aki K.; Kokubu, Yuko; Ohnishi, Keigoh; Nakajima, Yoshiro; Kato, Kaoru; Intoh, Atsushi; Takada, Hitomi; Yamakawa, Norio; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

2014-01-01

Background The pluripotent state of embryonic stem (ES) cells is controlled by a network of specific transcription factors. Recent studies also suggested the significant contribution of mitochondria on the regulation of pluripotent stem cells. However, the molecules involved in these regulations are still unknown. Methodology/Principal Findings In this study, we found that prohibitin 2 (PHB2), a pleiotrophic factor mainly localized in mitochondria, is a crucial regulatory factor for the homeostasis and differentiation of ES cells. PHB2 was highly expressed in undifferentiated mouse ES cells, and the expression was decreased during the differentiation of ES cells. Knockdown of PHB2 induced significant apoptosis in pluripotent ES cells, whereas enhanced expression of PHB2 contributed to the proliferation of ES cells. However, enhanced expression of PHB2 strongly inhibited ES cell differentiation into neuronal and endodermal cells. Interestingly, only PHB2 with intact mitochondrial targeting signal showed these specific effects on ES cells. Moreover, overexpression of PHB2 enhanced the processing of a dynamin-like GTPase (OPA1) that regulates mitochondrial fusion and cristae remodeling, which could induce partial dysfunction of mitochondria. Conclusions/Significance Our results suggest that PHB2 is a crucial mitochondrial regulator for homeostasis and lineage-specific differentiation of ES cells. PMID:24709813

Activation of the mouse Oct4 promoter in medaka embryonic stem cells and its use for ablation of spontaneous differentiation.

PubMed

Hong, Yunhan; Winkler, Christoph; Liu, Tongming; Chai, Guixuan; Schartl, Manfred

2004-07-01

The determination and maintenance of the cell fate is ultimately due to differential gene activity. In the mouse, expression of the transcription factor Oct4 is high in totipotent inner cell mass, germ cells and undifferentiated embryonic stem (ES) cells, but dramatically reduced or extinct upon differentiation. Here, we show that medaka blastula embryos and cells of the ES cell line MES1 are able to activate the Oct4 promoter. Ectopic expression of a fusion gene for beta-galactosidase and neomycin resistance from the Oct4 promoter conferred resistance to G418. G418 selection led to a homogeneous population of undifferentiated ES cells which were able to undergo induced or directed differentiation into various cell types including neuron-like cells and melanocytes. Furthermore, GFP-labeled GOF18geo-MES1 cells after differentiation ablation were able to contribute to a wide variety of organ systems derived from all the three germ layers. Most importantly, we show that drug ablation of differentiation on the basis of Oct4 promoter is a useful tool to improve ES cell cultivation and chimera formation: MES1 cells after differentiation ablation appeared to be better donors than the parental MES1 line, as the permissive number of input donor cells increases from 100 to 200, resulting in an enhanced degree of chimerism. Taken together, some transcription factors and cis-acting regulatory sequences controlling totipotency-specific gene expression appear to be conserved between mammals and fish, and medaka ES cells offer an in vitro system for characterizing the expression of totipotency-specific genes such as putative Oct4 homologs from fish.

Critical components of the pluripotency network are targets for the p300/CBP interacting protein (p/CIP) in embryonic stem cells.

PubMed

Chitilian, J M; Thillainadesan, G; Manias, J L; Chang, W Y; Walker, E; Isovic, M; Stanford, W L; Torchia, J

2014-01-01

p/CIP, also known as steroid receptor coactivator 3 (SRC-3)/Nuclear Receptor Coactivator 3 (NCoA3), is a transcriptional coactivator that binds liganded nuclear hormone receptors, as well as other transcription factors, and facilitates transcription through direct recruitment of accessory factors. We have found that p/CIP is highly expressed in undifferentiated mouse embryonic stem cells (mESCs) and is downregulated during differentiation. siRNA-mediated knockdown of p/CIP decreased transcript levels of Nanog, but not Oct4 or Sox2. Microarray expression analysis showed that Klf4, Tbx3, and Dax-1 are significantly downregulated in mESCs when p/CIP is knocked down. Subsequent chromatin immunoprecipitation (ChIP) analysis demonstrated that Tbx3, Klf4, and Dax-1 are direct transcriptional targets of p/CIP. Using the piggyBac transposition system, a mouse ESC line that expresses Flag-p/CIP in a doxycycline-dependent manner was generated. p/CIP overexpression increased the level of target genes and promoted the formation of undifferentiated colonies. Collectively, these results indicate that p/CIP contributes to the maintenance of ESC pluripotency through direct regulation of essential pluripotency genes. To better understand the mechanism by which p/CIP functions in ESC pluripotency, we integrated our ChIP and transcriptome data with published protein-protein interaction and promoter occupancy data to draft a p/CIP gene regulatory network. The p/CIP gene regulatory network identifies various feed-forward modules including one in which p/CIP activates members of the extended pluripotency network, demonstrating that p/CIP is a component of this extended network. © AlphaMed Press.

Human Embryonic Stem Cells Undergo Osteogenic Differentiation in Human Bone Marrow Stromal Cell Microenvironments

PubMed Central

Tong, Wilbur; Brown, Shelley E.; Krebsbach, Paul H.

2009-01-01

Human embryonic stem cells (hESCs) may offer an unlimited supply of cells that can be directed to differentiate into all cell types within the body and used in regenerative medicine for tissue and cell replacement therapies. Previous work has shown that exposing hESCs to exogenous factors such as dexamethasone, ascorbic acid and β-glycerophosphate can induce osteogenesis. The specific factors that induce osteogenic differentiation of hESCs have not been identified yet, however, it is possible that differentiated human bone marrow stromal cells (hMBSCs) may secrete factors within the local microenvironment that promote osteogenesis. Here we report that the lineage progression of hESCs to osteoblasts is achieved in the presence of soluble signaling factors derived from differentiated hBMSCs. For 28 days, hESCs were grown in a transwell co-culture system with hBMSCs that had been previously differentiated in growth medium containing defined osteogenic supplements for 7-24 days. As a control. hESCs were co-cultured with undifferentiated hBMSCs and alone. Von Kossa and Alizarin Red staining as well as immunohistochemistry confirmed that the hESCs co-cultured with differentiated hBMSCs formed mineralized bone nodules and secreted extracellular matrix protein osteocalcin (OCN). Quantitative Alizarin Red assays showed increased mineralization as compared to the control with undifferentiated hBMSCs. RT-PCR revealed the loss of pluripotent hESC markers with the concomitant gain of osteoblastic markers such as collagen type I, runx2, and osterix. We demonstrate that osteogenic growth factors derived from differentiated hBMSCs within the local microenvironment may help to promote hESC osteogenic differentiation. PMID:20671800

The expression of the class 1 glucose transporter isoforms in human embryonic stem cells, and the potential use of GLUT2 as a marker for pancreatic progenitor enrichment.

PubMed

Segev, Hana; Fishman, Betina; Schulman, Rita; Itskovitz-Eldor, Joseph

2012-07-01

Even before the first appearance of the developing pancreas, glucose is the major substrate in the growing embryo. The transport of glucose across cell membranes is facilitated by a family of membranal glucose transporters (GLUT). We analyzed changes in expression of class 1 glucose transporters (GLUT1-4) during human embryonic stem cell (hESC) and human induced pluripotent stem cell (hiPSC) differentiation, from undifferentiated cells to 28-day-old embryoid bodies (EBs). We also examined the potential use of GLUT2 as a marker for differentiating pancreatic progenitor cells. Using quantitative real time polymerase chain reaction (qPCR), western blot, and immunofluorescence, we observed enhanced expression of GLUT1 and GLUT2 during differentiation, but only minor change in GLUT3 expression. GLUT4 expression was found to be very low both at the RNA and in the protein levels. Expression of the early pancreatic transcription factor, pancreatic duodenal homeobox gene 1 (PDX1), correlated with GLUT2 expression, suggesting the potential use of GLUT2 as a surface marker for tracking pancreatic precursor cells. After sorting EBs according to their membranal GLUT2 expression, GLUT2 and PDX1 expression were found elevated, as was expression of other endodermal markers such as PAX4, NGN3, CXCR4, and SOX17. This simple method may be used to differentiate embryonic stem cells and to isolate from them, using GLUT2 as a surface marker, an enriched pancreatic progenitor cell population in order to achieve insulin-producing cells. The sorted GLUT2 cells may potentially be used in the future as insulin-producing cells for beta cell therapies.

Comparison of the glycosphingolipids of human-induced pluripotent stem cells and human embryonic stem cells.

PubMed

Säljö, Karin; Barone, Angela; Vizlin-Hodzic, Dzeneta; Johansson, Bengt R; Breimer, Michael E; Funa, Keiko; Teneberg, Susann

2017-04-01

High expectations are held for human-induced pluripotent stem cells (hiPSC) since they are established from autologous tissues thus overcoming the risk of allogeneic immune rejection when used in regenerative medicine. However, little is known regarding the cell-surface carbohydrate antigen profile of hiPSC compared with human embryonic stem cells (hESC). Here, glycosphingolipids were isolated from an adipocyte-derived hiPSC line, and hiPSC and hESC glycosphingolipids were compared by concurrent characterization by binding assays with carbohydrate-recognizing ligands and mass spectrometry. A high similarity between the nonacid glycosphingolipids of hiPSC and hESC was found. The nonacid glycosphingolipids P1 pentaosylceramide, x2 pentaosylceramide and H type 1 heptaosylceramide, not previously described in human pluripotent stem cells (hPSC), were characterized in both hiPSC and hESC. The composition of acid glycosphingolipids differed, with increased levels of GM3 ganglioside, and reduced levels of GD1a/GD1b in hiPSC when compared with hESC. In addition, the hESC glycosphingolipids sulf-globopentaosylceramide and sialyl-globotetraosylceramide were lacking in hiPSC. Neural stem cells differentiating from hiPSC had a reduced expression of sialyl-lactotetra, whereas expression of the GD1a ganglioside was significantly increased. Thus, while sialyl-lactotetra is a marker of undifferentiated hPSC, GD1a is a novel marker of neural differentiation. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Locust bean gum as an alternative polymeric coating for embryonic stem cell culture.

PubMed

Perestrelo, Ana Rubina; Grenha, Ana; Rosa da Costa, Ana M; Belo, José António

2014-07-01

Pluripotent embryonic stem cells (ESCs) have self-renewal capacity and the potential to differentiate into any cellular type depending on specific cues (pluripotency) and, therefore, have become a vibrant research area in the biomedical field. ESCs are usually cultured in gelatin or on top of a monolayer of feeder cells such as mitotically inactivated mouse embryonic fibroblasts (MEFsi). The latter is the gold standard support to maintain the ESCs in the pluripotent state. Examples of versatile, non-animal derived and inexpensive materials that are able to support pluripotent ESCs are limited. Therefore, our aim was to find a biomaterial able to support ESC growth in a pluripotent state avoiding laborious and time consuming parallel culture of MEFsi and as simple to handle as gelatin. Many of the new biomaterials used to develop stem cell microenvironments are using natural polymers adsorbed or covalently attached to the surface to improve the biocompatibility of synthetic polymers. Locust beam gum (LBG) is a natural, edible polymer, which has a wide range of potential applications in different fields, such as food and pharmaceutical industry, due to its biocompatibility, adhesiveness and thickening properties. The present work brings a natural system based on the use of LBG as a coating for ESC culture. Undifferentiated mouse ESCs were cultured on commercially available LBG to evaluate its potential in maintaining pluripotent ESCs. In terms of morphology, ESC colonies in LBG presented the regular dome shape with bright borders, similar to the colonies obtained in co-cultures with MEFsi and characteristic of pluripotent ESC colonies. In short-term cultures, ESC proliferation in LBG coating was similar to ESC cultured in gelatin and the cells maintained their viability. The activity of alkaline phosphatase and Nanog, Sox2 and Oct4 expression of mouse ESCs cultured in LBG were comparable or in some cases higher than in ESCs cultured in gelatin. An in vitro differentiation assay revealed that mouse ESCs cultured in LBG preserve their tri-lineage differentiation capacity. In conclusion, our data indicate that LBG coating promotes mouse ESC growth in an undifferentiated state demonstrating to be a viable, non-animal derived alternative to gelatin to support pluripotent mouse ESCs in culture. Copyright © 2014 Elsevier B.V. All rights reserved.

Aberrant patterns of X chromosome inactivation in a new line of human embryonic stem cells established in physiological oxygen concentrations.

PubMed

de Oliveira Georges, Juliana Andrea; Vergani, Naja; Fonseca, Simone Aparecida Siqueira; Fraga, Ana Maria; de Mello, Joana Carvalho Moreira; Albuquerque, Maria Cecília R Maciel; Fujihara, Litsuko Shimabukuro; Pereira, Lygia Veiga

2014-08-01

One of the differences between murine and human embryonic stem cells (ESCs) is the epigenetic state of the X chromosomes in female lines. Murine ESCs (mESCs) present two transcriptionally active Xs that will undergo the dosage compensation process of XCI upon differentiation, whereas most human ESCs (hESCs) spontaneously inactivate one X while keeping their pluripotency. Whether this reflects differences in embryonic development of mice and humans, or distinct culture requirements for the two kinds of pluripotent cells is not known. Recently it has been shown that hESCs established in physiological oxygen levels are in a stable pre-XCI state equivalent to that of mESCs, suggesting that culture in low oxygen concentration is enough to preserve that epigenetic state of the X chromosomes. Here we describe the establishment of two new lines of hESCs under physiological oxygen level and the characterization of the XCI state in the 46,XX line BR-5. We show that a fraction of undifferentiated cells present XIST RNA accumulation and single H3K27me foci, characteristic of the inactive X. Moreover, analysis of allele specific gene expression suggests that pluripotent BR-5 cells present completely skewed XCI. Our data indicate that physiological levels of oxygen are not sufficient for the stabilization of the pre-XCI state in hESCs.

Recent developments in testicular germ cell tumor research.

PubMed

van de Geijn, Gert-Jan M; Hersmus, Remko; Looijenga, Leendert H J

2009-03-01

Testicular germ cell tumors of adolescents and adults (TGCTs; the so-called type II variant) are the most frequent malignancies found in Caucasian males between 20 and 40 years of age. The incidence has increased over the last decades. TGCTs are divided into seminomas and nonseminomas, the latter consisting of the subgroups embryonal carcinoma, yolk-sac tumor, teratoma, and choriocarcinoma. The pathogenesis starts in utero, involving primordial germ cells/gonocytes that are blocked in their differentiation, and develops via the precursor lesion carcinoma in situ toward invasiveness. TGCTs are totipotent and can be considered as stem cell tumors. The developmental capacity of their cell of origin, the primordial germ cells/gonocyte, is demonstrated by the different tumor histologies of the invasive TGCTs. Seminoma represents the germ cell lineage, and embryonal carcinoma is the undifferentiated component, being the stem cell population of the nonseminomas. Somatic differentiation is seen in the teratomas (all lineages), whereas yolk-sac tumors and choriocarcinoma represent extra-embryonal differentiation. Seminomas are highly sensitive to irradiation and (DNA damaging) chemotherapy, whereas most nonseminomatous elements are less susceptible to radiation, although still sensitive to chemotherapy, with the exception of teratoma. To allow early diagnosis and follow up, appropriate markers are mandatory to discriminate between the different subgroups. In this review, a summary will be given related to several recent developments in TGCT research, especially selected because of their putative clinical impact.

Application of a Novel Population of Multipotent Stem Cells Derived from Skin Fibroblasts as Donor Cells in Bovine SCNT

PubMed Central

Pan, Shaohui; Chen, Wuju; Liu, Xu; Xiao, Jiajia; Wang, Yanqin; Liu, Jun; Du, Yue; Wang, Yongsheng; Zhang, Yong

2015-01-01

Undifferentiated stem cells are better donor cells for somatic cell nuclear transfer (SCNT), resulting in more offspring than more differentiated cells. While various stem cell populations have been confirmed to exist in the skin, progress has been restricted due to the lack of a suitable marker for their prospective isolation. To address this fundamental issue, a marker is required that could unambiguously prove the differentiation state of the donor cells. We therefore utilized magnetic activated cell sorting (MACS) to separate a homogeneous population of small SSEA-4+ cells from a heterogeneous population of bovine embryonic skin fibroblasts (BEF). SSEA-4+ cells were 8-10 μm in diameter and positive for alkaline phosphatase (AP). The percentage of SSEA-4+ cells within the cultured BEF population was low (2-3%). Immunocytochemistry and PCR analyses revealed that SSEA-4+ cells expressed pluripotency-related markers, and could differentiate into cells comprising all three germ layers in vitro. They remained undifferentiated over 20 passages in suspension culture. In addition, cloned embryos derived from SSEA-4 cells showed significant differences in cleavage rate and blastocyst development when compared with those from BEF and SSEA-4− cells. Moreover, blastocysts derived from SSEA-4+ cells showed a higher total cell number and lower apoptotic index as compared to BEF and SSEA-4– derived cells. It is well known that nuclei from pluripotent stem cells yield a higher cloning efficiency than those from adult somatic cells, however, pluripotent stem cells are relatively difficult to obtain from bovine. The SSEA-4+ cells described in the current study provide an attractive candidate for SCNT and a promising platform for the generation of transgenic cattle. PMID:25602959

Application of a novel population of multipotent stem cells derived from skin fibroblasts as donor cells in bovine SCNT.

PubMed

Pan, Shaohui; Chen, Wuju; Liu, Xu; Xiao, Jiajia; Wang, Yanqin; Liu, Jun; Du, Yue; Wang, Yongsheng; Zhang, Yong

2015-01-01

Undifferentiated stem cells are better donor cells for somatic cell nuclear transfer (SCNT), resulting in more offspring than more differentiated cells. While various stem cell populations have been confirmed to exist in the skin, progress has been restricted due to the lack of a suitable marker for their prospective isolation. To address this fundamental issue, a marker is required that could unambiguously prove the differentiation state of the donor cells. We therefore utilized magnetic activated cell sorting (MACS) to separate a homogeneous population of small SSEA-4(+) cells from a heterogeneous population of bovine embryonic skin fibroblasts (BEF). SSEA-4(+) cells were 8-10 μm in diameter and positive for alkaline phosphatase (AP). The percentage of SSEA-4(+) cells within the cultured BEF population was low (2-3%). Immunocytochemistry and PCR analyses revealed that SSEA-4(+) cells expressed pluripotency-related markers, and could differentiate into cells comprising all three germ layers in vitro. They remained undifferentiated over 20 passages in suspension culture. In addition, cloned embryos derived from SSEA-4 cells showed significant differences in cleavage rate and blastocyst development when compared with those from BEF and SSEA-4(-) cells. Moreover, blastocysts derived from SSEA-4(+) cells showed a higher total cell number and lower apoptotic index as compared to BEF and SSEA-4(-) derived cells. It is well known that nuclei from pluripotent stem cells yield a higher cloning efficiency than those from adult somatic cells, however, pluripotent stem cells are relatively difficult to obtain from bovine. The SSEA-4(+) cells described in the current study provide an attractive candidate for SCNT and a promising platform for the generation of transgenic cattle.

The Emerging Cell Biology of Thyroid Stem Cells

PubMed Central

Latif, Rauf; Minsky, Noga C.; Ma, Risheng

2011-01-01

Context: Stem cells are undifferentiated cells with the property of self-renewal and give rise to highly specialized cells under appropriate local conditions. The use of stem cells in regenerative medicine holds great promise for the treatment of many diseases, including those of the thyroid gland. Evidence Acquisition: This review focuses on the progress that has been made in thyroid stem cell research including an overview of cellular and molecular events (most of which were drawn from the period 1990–2011) and discusses the remaining problems encountered in their differentiation. Evidence Synthesis: Protocols for the in vitro differentiation of embryonic stem cells, based on normal developmental processes, have generated thyroid-like cells but without full thyrocyte function. However, agents have been identified, including activin A, insulin, and IGF-I, which are able to stimulate the generation of thyroid-like cells in vitro. In addition, thyroid stem/progenitor cells have been identified within the normal thyroid gland and within thyroid cancers. Conclusions: Advances in thyroid stem cell biology are providing not only insight into thyroid development but may offer therapeutic potential in thyroid cancer and future thyroid cell replacement therapy. PMID:21778219

From “ES-like” cells to induced pluripotent stem cells: A historical perspective in domestic animals

PubMed Central

Koh, Sehwon; Piedrahita, Jorge A.

2013-01-01

Pluripotent stem cells such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) provide great potential as cell sources for gene editing to generate genetically modified animals, as well as in the field of regenerative medicine. Stable, long-term ESCs have been established in laboratory mouse and rat, however, isolation of true pluripotent ESCs in domesticated animals such as pigs and dogs have been less successful. Initially, domesticated animal pluripotent cell lines were referred to as “ES-like” cells due to similar morphological characteristics to mouse ESCs but accompanied by a limited ability to proliferate in vitro in an undifferentiated state. That is, they shared some but not all the characteristics of true ESCs. More recently, advances in reprogramming using exogenous transcription factors, combined with the utilization of small chemical inhibitors of key biochemical pathways, have led to the isolation of induced pluripotent stem cells. In this review, we provide a historical perspective of the isolation of various types of pluripotent stem cells in domesticated animals. In addition, we summarize the latest progress and limitations in the derivation and application of induced pluripotent stem cells. PMID:24274415

Normal embryonic and germ cell development in mice lacking alpha 1,3-fucosyltransferase IX (Fut9) which show disappearance of stage-specific embryonic antigen 1.

PubMed

Kudo, Takashi; Kaneko, Mika; Iwasaki, Hiroko; Togayachi, Akira; Nishihara, Shoko; Abe, Kuniya; Narimatsu, Hisashi

2004-05-01

Stage-specific embryonic antigen 1 (SSEA-1), an antigenic epitope defined as a Lewis x carbohydrate structure, is expressed during the 8-cell to blastocyst stages in mouse embryos and in primordial germ cells, undifferentiated embryonic stem cells, and embryonic carcinoma cells. For many years, SSEA-1 has been implicated in the development of mouse embryos as a functional carbohydrate epitope in cell-to-cell interaction during morula compaction. In a previous study, alpha 1,3-fucosyltransferase IX (Fut9) exhibited very strong activity for the synthesis of Lewis x compared to other alpha 1,3-fucosyltransferases in an in vitro substrate specificity assay. Fut4 and Fut9 transcripts were expressed in mouse embryos. The Fut9 transcript was detected in embryonic-day-13.5 gonads containing primordial germ cells, but the Fut4 transcript was not. In order to identify the role of SSEA-1 and determine the key enzyme for SSEA-1 synthesis in vivo, we have generated Fut9-deficient (Fut9(-/-)) mice. Fut9(-/-) mice develop normally, with no gross phenotypic abnormalities, and are fertile. Immunohistochemical analysis revealed an absence of SSEA-1 expression in early embryos and primordial germ cells of Fut9(-/-) mice. Therefore, we conclude that expression of the SSEA-1 epitope in the developing mouse embryo is not essential for embryogenesis in vivo.

Transplant of Hepatocytes, Undifferentiated Mesenchymal Stem Cells, and In Vitro Hepatocyte-Differentiated Mesenchymal Stem Cells in a Chronic Liver Failure Experimental Model: A Comparative Study.

PubMed

El Baz, Hanan; Demerdash, Zeinab; Kamel, Manal; Atta, Shimaa; Salah, Faten; Hassan, Salwa; Hammam, Olfat; Khalil, Heba; Meshaal, Safa; Raafat, Inas

2018-02-01

Liver transplant is the cornerstone line of treatment for chronic liver diseases; however, the long list of complications and obstacles stand against this operation. Searching for new modalities for treatment of chronic liver illness is a must. In the present research, we aimed to compare the effects of transplant of undifferentiated human mesenchymal stem cells, in vitro differentiated mesenchymal stem cells, and adult hepatocytes in an experimental model of chronic liver failure. Undifferentiated human cord blood mesenchymal stem cells were isolated, pro-pagated, and characterized by morphology, gene expression analysis, and flow cytometry of surface markers and in vitro differentiated into hepatocyte-like cells. Rat hepatocytes were isolated by double perfusion technique. An animal model of chronic liver failure was developed, and undifferentiated human cord blood mesenchymal stem cells, in vitro hepato-genically differentiated mesenchymal stem cells, or freshly isolated rat hepatocytes were transplanted into a CCL4 cirrhotic experimental model. Animals were killed 3 months after transplant, and liver functions and histopathology were assessed. Compared with the cirrhotic control group, the 3 cell-treated groups showed improved alanine aminotransferase, aspartate aminotransferase, albumin, and bilirubin levels, with best results shown in the hepatocyte-treated group. Histopathologic examination of the treated groups showed improved fibrosis, with best results obtained in the undifferentiated mesenchymal stem cell-treated group. Both adult hepatocytes and cord blood mesenchymal stem cells proved to be promising candidates for cell-based therapy in liver regeneration on an experimental level. Improved liver function was evident in the hepatocyte-treated group, and fibrosis control was more evident in the undifferentiated mesenchymal stem cell-treated group.

Yap1 is dispensable for self-renewal but required for proper differentiation of mouse embryonic stem (ES) cells.

PubMed

Chung, HaeWon; Lee, Bum-Kyu; Uprety, Nadima; Shen, Wenwen; Lee, Jiwoon; Kim, Jonghwan

2016-04-01

Yap1 is a transcriptional co-activator of the Hippo pathway. The importance of Yap1 in early cell fate decision during embryogenesis has been well established, though its role in embryonic stem (ES) cells remains elusive. Here, we report that Yap1 plays crucial roles in normal differentiation rather than self-renewal of ES cells. Yap1-depleted ES cells maintain undifferentiated state with a typical colony morphology as well as robust alkaline phosphatase activity. These cells also retain comparable levels of the core pluripotent factors, such as Pou5f1 and Sox2, to the levels in wild-type ES cells without significant alteration of lineage-specific marker genes. Conversely, overexpression of Yap1 in ES cells promotes nuclear translocation of Yap1, resulting in disruption of self-renewal and triggering differentiation by up-regulating lineage-specific genes. Moreover, Yap1-deficient ES cells show impaired induction of lineage markers during differentiation. Collectively, our data demonstrate that Yap1 is a required factor for proper differentiation of mouse ES cells, while remaining dispensable for self-renewal. © 2016 The Authors.

The Sox2 promoter-driven CD63-GFP transgenic rat model allows tracking of neural stem cell-derived extracellular vesicles.

PubMed

Yoshimura, Aya; Adachi, Naoki; Matsuno, Hitomi; Kawamata, Masaki; Yoshioka, Yusuke; Kikuchi, Hisae; Odaka, Haruki; Numakawa, Tadahiro; Kunugi, Hiroshi; Ochiya, Takahiro; Tamai, Yoshitaka

2018-01-30

Extracellular vesicles (EVs) can modulate microenvironments by transferring biomolecules, including RNAs and proteins derived from releasing cells, to target cells. To understand the molecular mechanisms maintaining the neural stem cell (NSC) niche through EVs, a new transgenic (Tg) rat strain that can release human CD63-GFP-expressing EVs from the NSCs was established. Human CD63-GFP expression was controlled under the rat Sox2 promoter (Sox2/human CD63-GFP), and it was expressed in undifferentiated fetal brains. GFP signals were specifically observed in in vitro cultured NSCs obtained from embryonic brains of the Tg rats. We also demonstrated that embryonic NSC (eNSC)-derived EVs were labelled by human CD63-GFP. Furthermore, when we examined the transfer of EVs, eNSC-derived EVs were found to be incorporated into astrocytes and eNSCs, thus implying an EV-mediated communication between different cell types around NSCs. This new Sox2/human CD63-GFP Tg rat strain should provide resources to analyse the cell-to-cell communication via EVs in NSC microenvironments. © 2018. Published by The Company of Biologists Ltd.

Droplet Microarray Based on Patterned Superhydrophobic Surfaces Prevents Stem Cell Differentiation and Enables High-Throughput Stem Cell Screening.

PubMed

Tronser, Tina; Popova, Anna A; Jaggy, Mona; Bastmeyer, Martin; Levkin, Pavel A

2017-12-01

Over the past decades, stem cells have attracted growing interest in fundamental biological and biomedical research as well as in regenerative medicine, due to their unique ability to self-renew and differentiate into various cell types. Long-term maintenance of the self-renewal ability and inhibition of spontaneous differentiation, however, still remain challenging and are not fully understood. Uncontrolled spontaneous differentiation of stem cells makes high-throughput screening of stem cells also difficult. This further hinders investigation of the underlying mechanisms of stem cell differentiation and the factors that might affect it. In this work, a dual functionality of nanoporous superhydrophobic-hydrophilic micropatterns is demonstrated in their ability to inhibit differentiation of mouse embryonic stem cells (mESCs) and at the same time enable formation of arrays of microdroplets (droplet microarray) via the effect of discontinuous dewetting. Such combination makes high-throughput screening of undifferentiated mouse embryonic stem cells possible. The droplet microarray is used to investigate the development, differentiation, and maintenance of stemness of mESC, revealing the dependence of stem cell behavior on droplet volume in nano- and microliter scale. The inhibition of spontaneous differentiation of mESCs cultured on the droplet microarray for up to 72 h is observed. In addition, up to fourfold increased cell growth rate of mESCs cultured on our platform has been observed. The difference in the behavior of mESCs is attributed to the porosity and roughness of the polymer surface. This work demonstrates that the droplet microarray possesses the potential for the screening of mESCs under conditions of prolonged inhibition of stem cells' spontaneous differentiation. Such a platform can be useful for applications in the field of stem cell research, pharmacological testing of drug efficacy and toxicity, biomedical research as well as in the field of regenerative medicine and tissue engineering. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Alleviation of streptozotocin-induced diabetes in nude mice by stem cells derived from human first trimester umbilical cord.

PubMed

Cao, M; Zhang, J B; Dong, D D; Mou, Y; Li, K; Fang, J; Wang, Z Y; Chen, C; Zhao, J; Yie, S M

2015-10-16

Cells isolated from human first trimester umbilical cord perivascular layer (hFTM-PV) tissues display the pluripotent characteristics of stem cells. In this study, we examined whether hFTM-PV cells can differentiate into islet-like clusters (ILCs) in vitro, and whether transplantation of the hFTM-PV cells with and without differentiation in vitro can alleviate diabetes in nude mice. The hFTM-PV cells were differentiated into ILCs in vitro through a simple stepwise culture protocol. To examine the in vivo effects of the cells, the hFTM-PV cells with and without differentiation in vitro were transplanted into the abdominal cavity of nude mice with streptozotocin (STZ)-induced diabetes. Blood glucose levels, body weight, and the survival probability of the diabetic nude mice were then statistically analyzed. The hFTM-PV cells were successfully induced into ILCs that could release insulin in response to elevated concentrations of glucose in vitro. In transplantation experiments, we observed that mice transplanted with the undifferentiated hFTM-PV cells, embryonic body-like cell aggregations, or ILCs all demonstrated normalized hyperglycemia and showed improved survival rate compared with those without cell transplantation. The hFTM-PV cells have the ability to differentiate into ILCs in vitro and transplantations of undifferentiated and differentiated cells can alleviate STZ-induced diabetes in nude mice. This may offer a potential cell source for stem cell-based therapy for treating diabetes in the future.

Stem Cells and Regenerative Medicine: Myth or Reality of the 21th Century

PubMed Central

Stoltz, J.-F.; de Isla, N.; Li, Y. P.; Bensoussan, D.; Zhang, L.; Huselstein, C.; Chen, Y.; Decot, V.; Magdalou, J.; Li, N.; Reppel, L.; He, Y.

2015-01-01

Since the 1960s and the therapeutic use of hematopoietic stem cells of bone marrow origin, there has been an increasing interest in the study of undifferentiated progenitors that have the ability to proliferate and differentiate into various tissues. Stem cells (SC) with different potency can be isolated and characterised. Despite the promise of embryonic stem cells, in many cases, adult or even fetal stem cells provide a more interesting approach for clinical applications. It is undeniable that mesenchymal stem cells (MSC) from bone marrow, adipose tissue, or Wharton's Jelly are of potential interest for clinical applications in regenerative medicine because they are easily available without ethical problems for their uses. During the last 10 years, these multipotent cells have generated considerable interest and have particularly been shown to escape to allogeneic immune response and be capable of immunomodulatory activity. These properties may be of a great interest for regenerative medicine. Different clinical applications are under study (cardiac insufficiency, atherosclerosis, stroke, bone and cartilage deterioration, diabetes, urology, liver, ophthalmology, and organ's reconstruction). This review focuses mainly on tissue and organ regeneration using SC and in particular MSC. PMID:26300923

Differences in lymphocyte developmental potential between human embryonic stem cell and umbilical cord blood–derived hematopoietic progenitor cells

PubMed Central

Martin, Colin H.; Woll, Petter S.; Ni, Zhenya; Zúñiga-Pflücker, Juan Carlos

2008-01-01

Hematopoietic progenitor cells derived from human embryonic stem cells (hESCs) develop into diverse mature hematopoietic lineages, including lymphocytes. Whereas functional natural killer (NK) cells can be efficiently generated in vitro from hESC-derived CD34+ cells, studies of T- and B-cell development from hESCs have been much more limited. Here, we demonstrate that despite expressing functional Notch-1, CD34+ cells from hESCs did not derive T cells when cocultured with OP9 cells expressing Delta-like 1, or in fetal thymus organ culture. hESC-derived CD34+ cells also did not produce B cells in vitro. In contrast, CD34+ cells isolated from UCB routinely generated T and B cells when cultured in the same conditions. Notably, both undifferentiated hESCs, and sorted hESC-derived populations with hematopoietic developmental potential exhibited constitutive expression of ID family genes and of transcriptional targets of stem cell factor–induced signaling. These pathways both inhibit T-cell development and promote NK-cell development. Together, these results demonstrate fundamental differences between hESC-derived hematopoietic progenitors and analogous primary human cells. Therefore, hESCs can be more readily supported to differentiate into certain cell types than others, findings that have important implications for derivation of defined lineage-committed populations from hESCs. PMID:18621931

Differences in lymphocyte developmental potential between human embryonic stem cell and umbilical cord blood-derived hematopoietic progenitor cells.

PubMed

Martin, Colin H; Woll, Petter S; Ni, Zhenya; Zúñiga-Pflücker, Juan Carlos; Kaufman, Dan S

2008-10-01

Hematopoietic progenitor cells derived from human embryonic stem cells (hESCs) develop into diverse mature hematopoietic lineages, including lymphocytes. Whereas functional natural killer (NK) cells can be efficiently generated in vitro from hESC-derived CD34(+) cells, studies of T- and B-cell development from hESCs have been much more limited. Here, we demonstrate that despite expressing functional Notch-1, CD34(+) cells from hESCs did not derive T cells when cocultured with OP9 cells expressing Delta-like 1, or in fetal thymus organ culture. hESC-derived CD34(+) cells also did not produce B cells in vitro. In contrast, CD34(+) cells isolated from UCB routinely generated T and B cells when cultured in the same conditions. Notably, both undifferentiated hESCs, and sorted hESC-derived populations with hematopoietic developmental potential exhibited constitutive expression of ID family genes and of transcriptional targets of stem cell factor-induced signaling. These pathways both inhibit T-cell development and promote NK-cell development. Together, these results demonstrate fundamental differences between hESC-derived hematopoietic progenitors and analogous primary human cells. Therefore, hESCs can be more readily supported to differentiate into certain cell types than others, findings that have important implications for derivation of defined lineage-committed populations from hESCs.

Fetal Membranes-Derived Stem Cells Microenvironment.

PubMed

Favaron, Phelipe Oliveira; Miglino, Maria Angelica

2017-01-01

Recently, the regenerative medicine has been trying to congregate different areas such as tissue engineering and cellular therapy, in order to offer effective treatments to overcome several human and veterinary medical problems. In this regard, fetal membranes have been proposed as a powerful source for obtainment of multipotent stem cells with low immunogenicity, anti-inflammatory properties and nontumorigenicity properties for the treatment of several diseases, including replacing cells lost due to tissue injuries or degenerative diseases. Morpho-physiological data have shown that fetal membranes, especially the yolk sac and amnion play different functions according to the gestational period, which are direct related to the features of the microenvironment that their cells are subject. The characteristics of the microenvironment affect or controls important cellular events involved with proliferation, division and maintenance of the undifferentiated stage or differentiation, especially acting on the extracellular matrix components. Considering the importance of the microenvironment and the diversity of embryonic and fetal membrane-derived stem cells, this chapter will addressed advances in the isolation, phenotyping, characteristics of the microenvironment, and applications of yolk sac and amniotic membrane-derived stem cells for human and veterinary regenerative medicine.

Generation of functional cardiomyocytes from rat embryonic and induced pluripotent stem cells using feeder-free expansion and differentiation in suspension culture.

PubMed

Dahlmann, Julia; Awad, George; Dolny, Carsten; Weinert, Sönke; Richter, Karin; Fischer, Klaus-Dieter; Munsch, Thomas; Leßmann, Volkmar; Volleth, Marianne; Zenker, Martin; Chen, Yaoyao; Merkl, Claudia; Schnieke, Angelika; Baraki, Hassina; Kutschka, Ingo; Kensah, George

2018-01-01

The possibility to generate cardiomyocytes from pluripotent stem cells in vitro has enormous significance for basic research, disease modeling, drug development and heart repair. The concept of heart muscle reconstruction has been studied and optimized in the rat model using rat primary cardiovascular cells or xenogeneic pluripotent stem cell derived-cardiomyocytes for years. However, the lack of rat pluripotent stem cells (rPSCs) and their cardiovascular derivatives prevented the establishment of an authentic clinically relevant syngeneic or allogeneic rat heart regeneration model. In this study, we comparatively explored the potential of recently available rat embryonic stem cells (rESCs) and induced pluripotent stem cells (riPSCs) as a source for cardiomyocytes (CMs). We developed feeder cell-free culture conditions facilitating the expansion of undifferentiated rPSCs and initiated cardiac differentiation by embryoid body (EB)-formation in agarose microwell arrays, which substituted the robust but labor-intensive hanging drop (HD) method. Ascorbic acid was identified as an efficient enhancer of cardiac differentiation in both rPSC types by significantly increasing the number of beating EBs (3.6 ± 1.6-fold for rESCs and 17.6 ± 3.2-fold for riPSCs). These optimizations resulted in a differentiation efficiency of up to 20% cTnTpos rPSC-derived CMs. CMs showed spontaneous contractions, expressed cardiac markers and had typical morphological features. Electrophysiology of riPSC-CMs revealed different cardiac subtypes and physiological responses to cardio-active drugs. In conclusion, we describe rPSCs as a robust source of CMs, which is a prerequisite for detailed preclinical studies of myocardial reconstruction in a physiologically and immunologically relevant small animal model.

Ribociclib and Doxorubicin in Treating Patients With Metastatic or Advanced Soft Tissue Sarcomas That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-05-09

Metastatic Angiosarcoma; Metastatic Epithelioid Sarcoma; Metastatic Fibrosarcoma; Metastatic Leiomyosarcoma; Metastatic Liposarcoma; Metastatic Malignant Peripheral Nerve Sheath Tumor; Metastatic Synovial Sarcoma; Metastatic Undifferentiated Pleomorphic Sarcoma; Myxofibrosarcoma; Pleomorphic Rhabdomyosarcoma; Stage III Soft Tissue Sarcoma; Stage IV Soft Tissue Sarcoma; Undifferentiated (Embryonal) Sarcoma

The involvement of protein kinase C-ε in isoflurane induced preconditioning of human embryonic stem cell--derived Nkx2.5(+) cardiac progenitor cells.

PubMed

Song, In-Ae; Oh, Ah-Young; Kim, Jin-Hee; Choi, Young-Min; Jeon, Young-Tae; Ryu, Jung-Hee; Hwang, Jung-Won

2016-02-20

Anesthetic preconditioning can improve survival of cardiac progenitor cells exposed to oxidative stress. We investigated the role of protein kinase C and isoform protein kinase C-ε in isoflurane-induced preconditioning of cardiac progenitor cells exposed to oxidative stress. Cardiac progenitor cells were obtained from undifferentiated human embryonic stem cells. Immunostaining with anti-Nkx2.5 was used to confirm the differentiated cardiac progenitor cells. Oxidative stress was induced by H2O2 and FeSO4. For anesthetic preconditioning, cardiac progenitor cells were exposed to 0.25, 0.5, and 1.0 mM of isoflurane. PMA and chelerythrine were used for protein kinase C activation and inhibition, while εψRACK and εV1-2 were used for protein kinase C -ε activation and inhibition, respectively. Isoflurane-preconditioning decreased the death rate of Cardiac progenitor cells exposed to oxidative stress (death rates isoflurane 0.5 mM 12.7 ± 9.3%, 1.0 mM 12.0 ± 7.7% vs. control 31.4 ± 10.2%). Inhibitors of both protein kinase C and protein kinase C -ε abolished the preconditioning effect of isoflurane 0.5 mM (death rates 27.6 ± 13.5% and 25.9 ± 8.7% respectively), and activators of both protein kinase C and protein kinase C - ε had protective effects from oxidative stress (death rates 16.0 ± 3.2% and 10.6 ± 3.8% respectively). Both PKC and PKC-ε are involved in isoflurane-induced preconditioning of human embryonic stem cells -derived Nkx2.5(+) Cardiac progenitor cells under oxidative stress.

Glycome Diagnosis of Human Induced Pluripotent Stem Cells Using Lectin Microarray*

PubMed Central

Tateno, Hiroaki; Toyota, Masashi; Saito, Shigeru; Onuma, Yasuko; Ito, Yuzuru; Hiemori, Keiko; Fukumura, Mihoko; Matsushima, Asako; Nakanishi, Mio; Ohnuma, Kiyoshi; Akutsu, Hidenori; Umezawa, Akihiro; Horimoto, Katsuhisa; Hirabayashi, Jun; Asashima, Makoto

2011-01-01

Induced pluripotent stem cells (iPSCs) can now be produced from various somatic cell (SC) lines by ectopic expression of the four transcription factors. Although the procedure has been demonstrated to induce global change in gene and microRNA expressions and even epigenetic modification, it remains largely unknown how this transcription factor-induced reprogramming affects the total glycan repertoire expressed on the cells. Here we performed a comprehensive glycan analysis using 114 types of human iPSCs generated from five different SCs and compared their glycomes with those of human embryonic stem cells (ESCs; nine cell types) using a high density lectin microarray. In unsupervised cluster analysis of the results obtained by lectin microarray, both undifferentiated iPSCs and ESCs were clustered as one large group. However, they were clearly separated from the group of differentiated SCs, whereas all of the four SCs had apparently distinct glycome profiles from one another, demonstrating that SCs with originally distinct glycan profiles have acquired those similar to ESCs upon induction of pluripotency. Thirty-eight lectins discriminating between SCs and iPSCs/ESCs were statistically selected, and characteristic features of the pluripotent state were then obtained at the level of the cellular glycome. The expression profiles of relevant glycosyltransferase genes agreed well with the results obtained by lectin microarray. Among the 38 lectins, rBC2LCN was found to detect only undifferentiated iPSCs/ESCs and not differentiated SCs. Hence, the high density lectin microarray has proved to be valid for not only comprehensive analysis of glycans but also diagnosis of stem cells under the concept of the cellular glycome. PMID:21471226

Pluripotent cells in farm animals: state of the art and future perspectives.

PubMed

Nowak-Imialek, Monika; Niemann, Heiner

2012-01-01

Pluripotent cells, such as embryonic stem (ES) cells, embryonic germ cells and embryonic carcinoma cells are a unique type of cell because they remain undifferentiated indefinitely in in vitro culture, show self-renewal and possess the ability to differentiate into derivatives of the three germ layers. These capabilities make them a unique in vitro model for studying development, differentiation and for targeted modification of the genome. True pluripotent ESCs have only been described in the laboratory mouse and rat. However, rodent physiology and anatomy differ substantially from that of humans, detracting from the value of the rodent model for studies of human diseases and the development of cellular therapies in regenerative medicine. Recently, progress in the isolation of pluripotent cells in farm animals has been made and new technologies for reprogramming of somatic cells into a pluripotent state have been developed. Prior to clinical application of therapeutic cells differentiated from pluripotent stem cells in human patients, their survival and the absence of tumourigenic potential must be assessed in suitable preclinical large animal models. The establishment of pluripotent cell lines in farm animals may provide new opportunities for the production of transgenic animals, would facilitate development and validation of large animal models for evaluating ESC-based therapies and would thus contribute to the improvement of human and animal health. This review summarises the recent progress in the derivation of pluripotent and reprogrammed cells from farm animals. We refer to our recent review on this area, to which this article is complementary.

Periodontal tissue engineering strategies based on nonoral stem cells.

PubMed

Requicha, João Filipe; Viegas, Carlos Alberto; Muñoz, Fernando; Reis, Rui Luís; Gomes, Manuela Estima

2014-01-01

Periodontal disease is an inflammatory disease which constitutes an important health problem in humans due to its enormous prevalence and life threatening implications on systemic health. Routine standard periodontal treatments include gingival flaps, root planning, application of growth/differentiation factors or filler materials and guided tissue regeneration. However, these treatments have come short on achieving regeneration ad integrum of the periodontium, mainly due to the presence of tissues from different embryonic origins and their complex interactions along the regenerative process. Tissue engineering (TE) aims to regenerate damaged tissue by providing the repair site with a suitable scaffold seeded with sufficient undifferentiated cells and, thus, constitutes a valuable alternative to current therapies for the treatment of periodontal defects. Stem cells from oral and dental origin are known to have potential to regenerate these tissues. Nevertheless, harvesting cells from these sites implies a significant local tissue morbidity and low cell yield, as compared to other anatomical sources of adult multipotent stem cells. This manuscript reviews studies describing the use of non-oral stem cells in tissue engineering strategies, highlighting the importance and potential of these alternative stem cells sources in the development of advanced therapies for periodontal regeneration. Copyright © 2013 Wiley Periodicals, Inc.

The Role of Integrin α6 (CD49f) in Stem Cells: More than a Conserved Biomarker.

PubMed

Krebsbach, Paul H; Villa-Diaz, Luis G

2017-08-01

Stem cells have the capacity for self-renewal and differentiation into specialized cells that form and repopulated all tissues and organs, from conception to adult life. Depending on their capacity for differentiation, stem cells are classified as totipotent (ie, zygote), pluripotent (ie, embryonic stem cells), multipotent (ie, neuronal stem cells, hematopoietic stem cells, epithelial stem cells, etc.), and unipotent (ie, spermatogonial stem cells). Adult or tissue-specific stem cells reside in specific niches located in, or nearby, their organ or tissue of origin. There, they have microenvironmental support to remain quiescent, to proliferate as undifferentiated cells (self-renewal), and to differentiate into progenitors or terminally differentiated cells that migrate from the niche to perform specialized functions. The presence of proteins at the cell surface is often used to identify, classify, and isolate stem cells. Among the diverse groups of cell surface proteins used for these purposes, integrin α6, also known as CD49f, may be the only biomarker commonly found in more than 30 different populations of stem cells, including some cancer stem cells. This broad expression among stem cell populations indicates that integrin α6 may play an important and conserved role in stem cell biology, which is reaffirmed by recent demonstrations of its role maintaining self-renewal of pluripotent stem cells and breast and glioblastoma cancer stem cells. Therefore, this review intends to highlight and synthesize new findings on the importance of integrin α6 in stem cell biology.

EGF–FGF{sub 2} stimulates the proliferation and improves the neuronal commitment of mouse epidermal neural crest stem cells (EPI-NCSCs)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bressan, Raul Bardini; Melo, Fernanda Rosene; Almeida, Patricia Alves

Epidermal neural crest stem cells (EPI-NCSCs), which reside in the bulge of hair follicles, are attractive candidates for several applications in cell therapy, drug screening and tissue engineering. As suggested remnants of the embryonic neural crest (NC) in an adult location, EPI-NCSCs are able to generate a wide variety of cell types and are readily accessible by a minimally invasive procedure. Since the combination of epidermal growth factor (EGF) and fibroblast growth factor type 2 (FGF{sub 2}) is mitogenic and promotes the neuronal commitment of various stem cell populations, we examined its effects in the proliferation and neuronal potential ofmore » mouse EPI-NCSCs. By using a recognized culture protocol of bulge whiskers follicles, we were able to isolate a population of EPI-NCSCs, characterized by the migratory potential, cell morphology and expression of phenotypic markers of NC cells. EPI-NCSCs expressed neuronal, glial and smooth muscle markers and exhibited the NC-like fibroblastic morphology. The treatment with the combination EGF and FGF{sub 2}, however, increased their proliferation rate and promoted the acquisition of a neuronal-like morphology accompanied by reorganization of neural cytoskeletal proteins βIII-tubulin and nestin, as well as upregulation of the pan neuronal marker βIII-tubulin and down regulation of the undifferentiated NC, glial and smooth muscle cell markers. Moreover, the treatment enhanced the response of EPI-NCSCs to neurogenic stimulation, as evidenced by induction of GAP43, and increased expression of Mash-1 in neuron-like cell, both neuronal-specific proteins. Together, the results suggest that the combination of EGF–FGF2 stimulates the proliferation and improves the neuronal potential of EPI-NCSCs similarly to embryonic NC cells, ES cells and neural progenitor/stem cells of the central nervous system and highlights the advantage of using EGF–FGF{sub 2} in neuronal differentiation protocols. - Highlights: • EPI-NCSCs express undifferentiated NC and lineage-specific markers. • EGF–FGF{sub 2} supports in vitro expansion of EPI-NCSCs. • EGF–FGF{sub 2} promotes acquisition of neuron-like morphology by EPI-NCSCs. • EGF–FGF{sub 2} up regulates the expression of the pan-neuronal marker βIII-tubulin. • EGF–FGF{sub 2} enhances the response of EPI-NCSCs to neurogenic stimulation in vitro.« less

New gene targets for glucagon-like peptide-1 during embryonic development and in undifferentiated pluripotent cells.

PubMed

Sanz, Carmen; Blázquez, Enrique

2011-09-01

In humans, glucagon-like peptide (GLP-1) functions during adult life as an incretin hormone with anorexigenic and antidiabetogenic properties. Also, the therapeutic potential of GLP-1 in preventing the adipocyte hyperplasia associated with obesity and in bolstering the maintenance of human mesenchymal stem cell (hMSC) stores by promoting the proliferation and cytoprotection of hMSC seems to be relevant. Since these observations suggest a role for GLP-1 during developmental processes, the aim of the present work was to characterize GLP-1 in early development as well as its gene targets in mouse embryonic stem (mES) cells. Mouse embryos E6, E8, and E10.5 and pluripotent mES were used for the inmunodetection of GLP-1 and GLP-1 receptor. Quantitative real-time PCR was used to determine the expression levels of GLP-1R in several tissues from E12.5 mouse embryos. Additionally, GLP-1 gene targets were studied in mES by multiple gene expression analyses. GLP-1 and its receptors were identified in mES and during embryonic development. In pluripotent mES, GLP-1 modified the expression of endodermal, ectodermal, and mesodermal gene markers as well as sonic hedgehog, noggin, members of the fibroblast and hepatic growth factor families, and others involved in pancreatic development. Additionally, GLP-1 promoted the expression of the antiapoptotic gene bcl2 and at the same time reduced proapoptotic caspase genes. Our results indicate that apart from the effects and therapeutic benefits of GLP-1 in adulthood, it may have additional gene targets in mES cells during embryonic life. Furthermore, the pathophysiological implications of GLP-1 imbalance in adulthood may have a counterpart during development.

Huntington disease iPSCs show early molecular changes in intracellular signaling, the expression of oxidative stress proteins and the p53 pathway

PubMed Central

Szlachcic, Wojciech J.; Switonski, Pawel M.; Krzyzosiak, Wlodzimierz J.; Figlerowicz, Marek; Figiel, Maciej

2015-01-01

ABSTRACT Huntington disease (HD) is a brain disorder characterized by the late onset of motor and cognitive symptoms, even though the neurons in the brain begin to suffer dysfunction and degeneration long before symptoms appear. There is currently no cure. Several molecular and developmental effects of HD have been identified using neural stem cells (NSCs) and differentiated cells, such as neurons and astrocytes. Still, little is known regarding the molecular pathogenesis of HD in pluripotent cells, such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). Therefore, we examined putative signaling pathways and processes involved in HD pathogenesis in pluripotent cells. We tested naïve mouse HD YAC128 iPSCs and two types of human HD iPSC that were generated from HD and juvenile-HD patients. Surprisingly, we found that a number of changes affecting cellular processes in HD were also present in undifferentiated pluripotent HD iPSCs, including the dysregulation of the MAPK and Wnt signaling pathways and the dysregulation of the expression of genes related to oxidative stress, such as Sod1. Interestingly, a common protein interactor of the huntingtin protein and the proteins in the above pathways is p53, and the expression of p53 was dysregulated in HD YAC128 iPSCs and human HD iPSCs. In summary, our findings demonstrate that multiple molecular pathways that are characteristically dysregulated in HD are already altered in undifferentiated pluripotent cells and that the pathogenesis of HD might begin during the early stages of life. PMID:26092128

Effects of ß-TCP scaffolds on neurogenic and osteogenic differentiation of human embryonic stem cells.

PubMed

Arpornmaeklong, Premjit; Pressler, Michael J

2018-01-01

Extracellular matrix (ECM) and adhesion molecules play crucial roles in regulating growth and differentiation of stem cells. The current study aimed to investigate the effects of beta-tricalcium phosphate (ß-TCP) scaffolds on differentiation and expression of ECM and adhesion molecules of human embryonic stem cells (hESCs). Undifferentiated hESCs were seeded on ß-TCP scaffolds and cell culture plates and cultured in growth and osteogenic medium for 21 days. Scanning electron microscopy (SEM) displayed adhesion and growth of hESCs on the porous ß-TCP scaffolds. Histological analysis, immunohistochemical staining and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) demonstrated that the scaffolds supported growth and differentiation of hESCs. Expression levels of neural crest related genes (AP2a, FoxD3, HNK1, P75, Sox1, Sox10) and osteoblast-related genes (Runx2, SPP1 and BGLA) on the scaffolds in osteogenic medium were significantly higher than on the scaffolds in growth and cell culture plates in osteogenic medium, respectively (p<0.05). Polymerase chain reaction array experiments demonstrated increased expression of ECM and adhesion molecule-related genes on the scaffolds. In conclusion, osteoconductive scaffolds such as ß-TCP scaffolds promoted differentiation of hESCs, particularly expression of genes related to neural crest stem cell and osteoblastic differentiations. Beta-TCP scaffolds could be an alternative cell culture substrate for neural crest and osteogenic differentiation of hESCs. Optimization of culture medium may be necessary to enhance lineage restriction of hESCs on the ß-TCP scaffolds. Copyright © 2017 Elsevier GmbH. All rights reserved.

Nicotinamide induces differentiation of embryonic stem cells into insulin-secreting cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaca, Pilar; Berna, Genoveva; Araujo, Raquel

2008-03-10

The poly(ADP-ribose) polymerase (PARP) inhibitor, nicotinamide, induces differentiation and maturation of fetal pancreatic cells. In addition, we have previously reported evidence that nicotinamide increases the insulin content of cells differentiated from embryonic stem (ES) cells, but the possibility of nicotinamide acting as a differentiating agent on its own has never been completely explored. Islet cell differentiation was studied by: (i) X-gal staining after neomycin selection; (ii) BrdU studies; (iii) single and double immunohistochemistry for insulin, C-peptide and Glut-2; (iv) insulin and C-peptide content and secretion assays; and (v) transplantation of differentiated cells, under the kidney capsule, into streptozotocin (STZ)-diabetic mice.more » Here we show that undifferentiated mouse ES cells treated with nicotinamide: (i) showed an 80% decrease in cell proliferation; (ii) co-expressed insulin, C-peptide and Glut-2; (iii) had values of insulin and C-peptide corresponding to 10% of normal mouse islets; (iv) released insulin and C-peptide in response to stimulatory glucose concentrations; and (v) after transplantation into diabetic mice, normalized blood glucose levels over 7 weeks. Our data indicate that nicotinamide decreases ES cell proliferation and induces differentiation into insulin-secreting cells. Both aspects are very important when thinking about cell therapy for the treatment of diabetes based on ES cells.« less

Improving Embryonic Stem Cell Expansion through the Combination of Perfusion and Bioprocess Model Design

PubMed Central

Yeo, David; Kiparissides, Alexandros; Cha, Jae Min; Aguilar-Gallardo, Cristobal; Polak, Julia M.; Tsiridis, Elefterios; Pistikopoulos, Efstratios N.; Mantalaris, Athanasios

2013-01-01

Background High proliferative and differentiation capacity renders embryonic stem cells (ESCs) a promising cell source for tissue engineering and cell-based therapies. Harnessing their potential, however, requires well-designed, efficient and reproducible expansion and differentiation protocols as well as avoiding hazardous by-products, such as teratoma formation. Traditional, standard culture methodologies are fragmented and limited in their fed-batch feeding strategies that afford a sub-optimal environment for cellular metabolism. Herein, we investigate the impact of metabolic stress as a result of inefficient feeding utilizing a novel perfusion bioreactor and a mathematical model to achieve bioprocess improvement. Methodology/Principal Findings To characterize nutritional requirements, the expansion of undifferentiated murine ESCs (mESCs) encapsulated in hydrogels was performed in batch and perfusion cultures using bioreactors. Despite sufficient nutrient and growth factor provision, the accumulation of inhibitory metabolites resulted in the unscheduled differentiation of mESCs and a decline in their cell numbers in the batch cultures. In contrast, perfusion cultures maintained metabolite concentration below toxic levels, resulting in the robust expansion (>16-fold) of high quality ‘naïve’ mESCs within 4 days. A multi-scale mathematical model describing population segregated growth kinetics, metabolism and the expression of selected pluripotency (‘stemness’) genes was implemented to maximize information from available experimental data. A global sensitivity analysis (GSA) was employed that identified significant (6/29) model parameters and enabled model validation. Predicting the preferential propagation of undifferentiated ESCs in perfusion culture conditions demonstrates synchrony between theory and experiment. Conclusions/Significance The limitations of batch culture highlight the importance of cellular metabolism in maintaining pluripotency, which necessitates the design of suitable ESC bioprocesses. We propose a novel investigational framework that integrates a novel perfusion culture platform (controlled metabolic conditions) with mathematical modeling (information maximization) to enhance ESC bioprocess productivity and facilitate bioprocess optimization. PMID:24339957

Editorial: Our top 10 developments in stem cell biology over the last 30 years.

PubMed

Armstrong, Lyle; Lako, Majlinda; Buckley, Noel; Lappin, Terry R J; Murphy, Martin J; Nolta, Jan A; Pittenger, Mark; Stojkovic, Miodrag

2012-01-01

To celebrate 30 years of peer-reviewed publication of cutting edge stem cell research in Stem Cells, the first journal devoted to this promising field, we pause to review how far we have come in the three-decade lifetime of the Journal. To do this, we will present our views of the 10 most significant developments that have advanced stem cell biology where it is today. With the increasing rate of new data, it is natural that the bulk of these developments would have occurred in recent years, but we must not think that stem cell biology is a young science. The idea of a stem cell has actually been around for quite a long time having appeared in the scientific literature as early as 1868 with Haeckels' concept of a stamzelle as an uncommitted or undifferentiated cell responsible for producing many types of new cells to repair the body [Naturliche Schopfungsgeschichte, 1868; Berlin: Georg Reimer] but it took many years to obtain hard evidence in support of this theory. Not until the work of James Till and Ernest McCulloch in the 1960s did we have proof of the existence of stem cells and until the derivation of embryonal carcinoma cells in the 1960s-1970s and the first embryonic stem cell in 1981, such adult or tissue-specific stem cells were the only known class. The first issue of Stem Cells was published in 1981; no small wonder that most of its papers were devoted to hematopoietic progenitors. More recently, induced pluripotent stem cells (iPSCs) have been developed, and this is proving to be a fertile area of investigation as shown by the volume of publications appearing not only in Stem Cells but also in other journals over the last 5 years. The reader will note that many of the articles in this special issue are concerned with iPSC; however, this reflects the current surge of interest in the topic rather than any deliberate attempt to ignore other areas of stem cell investigation. Copyright © 2011 AlphaMed Press.

Endogenous production of fibronectin is required for self-renewal of cultured mouse embryonic stem cells

PubMed Central

Hunt, Geoffrey C.; Singh, Purva; Schwarzbauer, Jean E.

2012-01-01

Pluripotent cells are attached to the extracellular matrix (ECM) as they make cell fate decisions within the stem cell niche. Here we show that the ubiquitous ECM protein fibronectin is required for self-renewal decisions by cultured mouse embryonic stem (mES) cells. Undifferentiated mES cells produce fibronectin and assemble a fibrillar matrix. Increasing the level of substrate fibronectin increased cell spreading and integrin receptor signaling through focal adhesion kinase, while concomitantly inducing the loss of Nanog and Oct4 self-renewal markers. Conversely, reducing fibronectin production by mES cells growing on a feeder-free gelatin substrate caused loss of cell adhesion, decreased integrin signaling, and decreased expression of self-renewal markers. These effects were reversed by providing the cells with exogenous fibronectin, thereby restoring adhesion to the gelatin substrate. Interestingly, mES cells do not adhere directly to the gelatin substrate, but rather adhere indirectly through gelatin-bound fibronectin, which facilitates self-renewal via its effects on cell adhesion. These results provide new insights into the mechanism of regulation of self-renewal by growth on a gelatin-coated surface. The effects of increasing or decreasing fibronectin levels show that self-renewal depends on an intermediate level of cell-fibronectin interactions. By providing cell adhesive signals that can act with other self-renewal factors to maintain mES cell pluripotency, fibronectin is therefore a necessary component of the self-renewal signaling pathway in culture. PMID:22710062

Endogenous production of fibronectin is required for self-renewal of cultured mouse embryonic stem cells.

PubMed

Hunt, Geoffrey C; Singh, Purva; Schwarzbauer, Jean E

2012-09-10

Pluripotent cells are attached to the extracellular matrix (ECM) as they make cell fate decisions within the stem cell niche. Here we show that the ubiquitous ECM protein fibronectin is required for self-renewal decisions by cultured mouse embryonic stem (mES) cells. Undifferentiated mES cells produce fibronectin and assemble a fibrillar matrix. Increasing the level of substrate fibronectin increased cell spreading and integrin receptor signaling through focal adhesion kinase, while concomitantly inducing the loss of Nanog and Oct4 self-renewal markers. Conversely, reducing fibronectin production by mES cells growing on a feeder-free gelatin substrate caused loss of cell adhesion, decreased integrin signaling, and decreased expression of self-renewal markers. These effects were reversed by providing the cells with exogenous fibronectin, thereby restoring adhesion to the gelatin substrate. Interestingly, mES cells do not adhere directly to the gelatin substrate, but rather adhere indirectly through gelatin-bound fibronectin, which facilitates self-renewal via its effects on cell adhesion. These results provide new insights into the mechanism of regulation of self-renewal by growth on a gelatin-coated surface. The effects of increasing or decreasing fibronectin levels show that self-renewal depends on an intermediate level of cell-fibronectin interactions. By providing cell adhesive signals that can act with other self-renewal factors to maintain mES cell pluripotency, fibronectin is therefore a necessary component of the self-renewal signaling pathway in culture. Copyright © 2012 Elsevier Inc. All rights reserved.

GSK3 Inhibitor-BIO Regulates Proliferation of Immortalized Pancreatic Mesenchymal Stem Cells (iPMSCs)

PubMed Central

Cao, Hui; Chu, Yuankui; Lv, Xiao; Qiu, Pubin; Liu, Chao; Zhang, Huiru; Li, Dan; Peng, Sha; Dou, Zhongying; Hua, Jinlian

2012-01-01

Background The small molecule 6-bromoindirubin-30-oxime (BIO), a glycogen synthase kinase 3 (GSK3) inhibitor, is a pharmacological agent known to maintain self-renewal in human and mouse embryonic stem cells (ESCs). However, the precise role of GSK3 in immortalized pancreatic mesenchymal stem cells (iPMSCs) growth and survival is not completely understood at present. Results To determine whether this molecule is involved in controlling the proliferation of iPMSCs, we examined the effect of BIO on iPMSCs. We found that the inactivation of GSK3 by BIO can robustly stimulate iPMSCs proliferation and mass formation as shown by QRT-PCR, western blotting, 5-Bromo-2-deoxyuridine (BrdU) immunostaining assay and tunel assay. However, we did not find the related roles of BIO on β cell differentiation by immunostaining, QRT-PCR assay, glucose-stimulated insulin release and C-peptide content analysis. Conclusions These results suggest that BIO plays a key role in the regulation of cell mass proliferation and maintenance of the undifferentiated state of iPMSCs. PMID:22384031

Diploid, but not haploid, human embryonic stem cells can be derived from microsurgically repaired tripronuclear human zygotes

PubMed Central

Fan, Yong; Li, Rong; Huang, Jin; Yu, Yang; Qiao, Jie

2013-01-01

Human embryonic stem cells have shown tremendous potential in regenerative medicine, and the recent progress in haploid embryonic stem cells provides new insights for future applications of embryonic stem cells. Disruption of normal fertilized embryos remains controversial; thus, the development of a new source for human embryonic stem cells is important for their usefulness. Here, we investigated the feasibility of haploid and diploid embryo reconstruction and embryonic stem cell derivation using microsurgically repaired tripronuclear human zygotes. Diploid and haploid zygotes were successfully reconstructed, but a large proportion of them still had a tripolar spindle assembly. The reconstructed embryos developed to the blastocyst stage, although the loss of chromosomes was observed in these zygotes. Finally, triploid and diploid human embryonic stem cells were derived from tripronuclear and reconstructed zygotes (from which only one pronucleus was removed), but haploid human embryonic stem cells were not successfully derived from the reconstructed zygotes when two pronuclei were removed. Both triploid and diploid human embryonic stem cells showed the general characteristics of human embryonic stem cells. These results indicate that the lower embryo quality resulting from abnormal spindle assembly contributed to the failure of the haploid embryonic stem cell derivation. However, the successful derivation of diploid embryonic stem cells demonstrated that microsurgical tripronuclear zygotes are an alternative source of human embryonic stem cells. In the future, improving spindle assembly will facilitate the application of triploid zygotes to the field of haploid embryonic stem cells. PMID:23255130

Induction of intermediate mesoderm by retinoic acid receptor signaling from differentiating mouse embryonic stem cells.

PubMed

Oeda, Shiho; Hayashi, Yohei; Chan, Techuan; Takasato, Minoru; Aihara, Yuko; Okabayashi, Koji; Ohnuma, Kiyoshi; Asashima, Makoto

2013-01-01

Renal lineages including kidney are derived from intermediate mesoderm, which are differentiated from a subset of caudal undifferentiated mesoderm. The inductive mechanisms of mammalian intermediate mesoderm and renal lineages are still poorly understood. Mouse embryonic stem cells (mESCs) can be a good in vitro model to reconstitute the developmental pathway of renal lineages and to analyze the mechanisms of the sequential differentiation. We examined the effects of Activin A and retinoic acid (RA) on the induction of intermediate mesoderm from mESCs under defined, serum-free, adherent, monolayer culture conditions. We measured the expression level of intermediate mesodermal marker genes and examined the developmental potential of the differentiated cells into kidney using an ex vivo transplantation assay. Adding Activin A followed by RA to mESC cultures induced the expression of marker genes and proteins for intermediate mesoderm, odd-skipped related 1 (Osr1) and Wilm’s Tumor 1 (Wt1). These differentiated cells integrated into laminin-positive tubular cells and Pax2-positive renal cells in cultured embryonic kidney explants. We demonstrated that intermediate mesodermal marker expression was also induced by RA receptor (RAR) agonist, but not by retinoid X receptor (RXR) agonists. Furthermore, the expression of these markers was decreased by RAR antagonists. We directed the differentiation of mESCs into intermediate mesoderm using Activin A and RA and revealed the role of RAR signaling in this differentiation. These methods and findings will improve our understanding of renal lineage development and could contribute to the regenerative medicine of kidney.

Establishment of goat embryonic stem cells from in vivo produced blastocyst-stage embryos.

PubMed

Behboodi, E; Bondareva, A; Begin, I; Rao, K; Neveu, N; Pierson, J T; Wylie, C; Piero, F D; Huang, Y J; Zeng, W; Tanco, V; Baldassarre, H; Karatzas, C N; Dobrinski, I

2011-03-01

Embryonic stem (ES) cells with the capacity for germ line transmission have only been verified in mouse and rat. Methods for derivation, propagation, and differentiation of ES cells from domestic animals have not been fully established. Here, we describe derivation of ES cells from goat embryos. In vivo-derived embryos were cultured on goat fetal fibroblast feeders. Embryos either attached to the feeder layer or remained floating and expanded in culture. Embryos that attached showed a prominent inner cell mass (ICM) and those that remained floating formed structures resembling ICM disks surrounded by trophectodermal cells. ICM cells and embryonic disks were isolated mechanically, cultured on feeder cells in the presence of hLIF, and outgrown into ES-like colonies. Two cell lines were cultured for 25 passages and stained positive for alkaline phosphatase, POU5F1, NANOG, SOX2, SSEA-1, and SSEA-4. Embryoid bodies formed in suspension culture without hLIF. One cell line was cultured for 2 years (over 120 passages). This cell line differentiated in vitro into epithelia and neuronal cells, and could be stably transfected and selected for expression of a fluorescent marker. When cells were injected into SCID mice, teratomas were identified 5-6 weeks after transplantation. Expression of known ES cell markers, maintenance in vitro for 2 years in an undifferentiated state, differentiation in vitro, and formation of teratomas in immunodeficient mice provide evidence that the established cell line represents goat ES cells. This also is the first report of teratoma formation from large animal ES cells. Copyright © 2011 Wiley-Liss, Inc.

Growth enhancement by embryonic fibroblasts upon cotransplantation of noncommitted pig embryonic tissues with fully committed organs.

PubMed

Cohen, Sivan; Tchorsh-Yutsis, Dalit; Aronovich, Anna; Tal, Orna; Eventov-Friedman, Smadar; Katchman, Helena; Klionsky, Yael; Shezen, Elias; Reisner, Yair

2010-05-27

We recently defined the optimal gestational time windows for the transplantation of several embryonic tissues. We showed that the liver and kidney obtained from E28 pig embryos can grow and differentiate normally after transplantation, whereas 1 week earlier in gestation, these tissues develop into teratoma-like structures or fibrotic mass. In this study, we investigated whether cotransplantation of E28 with E21 tissue could control its tumorogenic potential, or alternatively whether the stem cells derived from the earlier tissue contribute to the growth of the more committed one. Pig embryonic precursors from E21 and E28 gestational age were transplanted alone or together, into nonobese diabetic/severe combined immunodeficiency mice, and their growth and differentiation was evaluated by immunohistology. In situ analysis, based on sex disparity between the E21 and E28 tissues, was used to identify the tissue source. In some experiments, mouse embryonic fibroblasts (MEF) were cotransplanted with E28 liver, and their effect was evaluated. E28 tissues could not abrogate the propensity of the cells within the undifferentiated tissue to form teratoma-like structures. However, E21 kidney or liver tissue markedly enhanced the growth and function of E28 kidney, liver, and heart grafts. Moreover, similar growth enhancement was observed on coimplantation of E28 liver tissue with MEF or on infusion of MEF culture medium, indicating that this enhancement is likely mediated through soluble factors secreted by the fibroblasts. Our results suggest a novel approach for the enhancement of growth and differentiation of transplanted embryonic tissues by the use of soluble factors secreted by embryonic fibroblasts.

Stem cells: a revolution in therapeutics-recent advances in stem cell biology and their therapeutic applications in regenerative medicine and cancer therapies.

PubMed

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

2007-09-01

Basic and clinical research accomplished during the last few years on embryonic, fetal, amniotic, umbilical cord blood, and adult stem cells has constituted a revolution in regenerative medicine and cancer therapies by providing the possibility of generating multiple therapeutically useful cell types. These new cells could be used for treating numerous genetic and degenerative disorders. Among them, age-related functional defects, hematopoietic and immune system disorders, heart failures, chronic liver injuries, diabetes, Parkinson's and Alzheimer's diseases, arthritis, and muscular, skin, lung, eye, and digestive disorders as well as aggressive and recurrent cancers could be successfully treated by stem cell-based therapies. This review focuses on the recent advancements in adult stem cell biology in normal and pathological conditions. We describe how these results have improved our understanding on critical and unique functions of these rare sub-populations of multipotent and undifferentiated cells with an unlimited self-renewal capacity and high plasticity. Finally, we discuss some major advances to translate the experimental models on ex vivo and in vivo expanded and/or differentiated stem cells into clinical applications for the development of novel cellular therapies aimed at repairing genetically altered or damaged tissues/organs in humans. A particular emphasis is made on the therapeutic potential of different tissue-resident adult stem cell types and their in vivo modulation for treating and curing specific pathological disorders.

Spermatogonial stem cells from domestic animals: progress and prospects.

PubMed

Zheng, Yi; Zhang, Yaqing; Qu, Rongfeng; He, Ying; Tian, Xiue; Zeng, Wenxian

2014-03-01

Spermatogenesis, an elaborate and male-specific process in adult testes by which a number of spermatozoa are produced constantly for male fertility, relies on spermatogonial stem cells (SSCs). As a sub-population of undifferentiated spermatogonia, SSCs are capable of both self-renewal (to maintain sufficient quantities) and differentiation into mature spermatozoa. SSCs are able to convert to pluripotent stem cells during in vitro culture, thus they could function as substitutes for human embryonic stem cells without ethical issues. In addition, this process does not require exogenous transcription factors necessary to produce induced-pluripotent stem cells from somatic cells. Moreover, combining genetic engineering with germ cell transplantation would greatly facilitate the generation of transgenic animals. Since germ cell transplantation into infertile recipient testes was first established in 1994, in vivo and in vitro study and manipulation of SSCs in rodent testes have been progressing at a staggering rate. By contrast, their counterparts in domestic animals, despite the failure to reach a comparable level, still burgeoned and showed striking advances. This review outlines the recent progressions of characterization, isolation, in vitro propagation, and transplantation of spermatogonia/SSCs from domestic animals, thereby shedding light on future exploration of these cells with high value, as well as contributing to the development of reproductive technology for large animals.

The human embryonic stem cell proteome revealed by multidimensional fractionation followed by tandem mass spectrometry

PubMed Central

Zhao, Peng; Schulz, Thomas C.; Sherrer, Eric S.; Weatherly, D. Brent; Robins, Allan J.; Wells, Lance

2015-01-01

Human embryonic stem cells (hESCs) have received considerable attention due to their therapeutic potential and usefulness in understanding early development and cell fate commitment. In order to appreciate the unique properties of these pluripotent, self-renewing cells, we have performed an in-depth multidimensional fractionation followed by LC-MS/MS analysis of the hESCs harvested from defined media to elucidate expressed, phosphorylated, O-linked β-N-acetylglucosamine (O-GlcNAc) modified, and secreted proteins. From the triplicate analysis, we were able to assign more than 3000 proteins with less than 1% false-discovery rate. This analysis also allowed us to identify nearly 500 phosphorylation sites and 68 sites of O-GlcNAc modification with the same high confidence. Investigation of the phosphorylation sites allowed us to deduce the set of kinases that are likely active in these cells. We also identified more than 100 secreted proteins of hESCs that likely play a role in extracellular matrix formation and remodeling, as well as autocrine signaling for self-renewal and maintenance of the undifferentiated state. Finally, by performing in-depth analysis in triplicate, spectral counts were obtained for these proteins and posttranslationally modified peptides, which will allow us to perform relative quantitative analysis between these cells and any derived cell type in the future. PMID:25367160

Stat3 phosphorylation is required for embryonic stem cells ground state maintenance in 2i culture media.

PubMed

Wang, Dan; Sang, Hui; Zhang, Kaiyue; Nie, Yan; Zhao, Shuang; Zhang, Yan; He, Ningning; Wang, Yuebing; Xu, Yang; Xie, Xiaoyan; Li, Zongjin; Liu, Na

2017-05-09

Embryonic stem cells (ES cells) can be maintained its undifferentiated state with feeder cells or LIF, which can activate Jak/Stat3 pathway. Recently, it has been reported a new culture condition comprising serum-free medium with ERK and GSK3β inhibitors (2i) could drive ES cells into a state of pluripotency more like inner cell mass (ICM) in mouse blastocysts called ground state. However, although 2i could sustain ES cells self-renewal, LIF is routinely added. The roles of Stat3 activation are still unclear now. Here we investigated whether Jak/Stat3 might also contribute to the induction of ground state pluripotency. We introduced a lentiviral construct with 7-repeat Stat3-binding sequence to drive Renilla luciferase into ES cells, which can be used as a reporter to detect Stat3 activation by noninvasive bioluminescence imaging. Using this ES cells, we investigated the role of Stat3 activation in ground state maintenance. The results showed that Stat3 could be activated by 2i. Stattic, a chemical inhibitor of Stat3 phosphorylation, could effectively inhibit Stat3 activation in ES cells. When Stat3 activation was suppressed, ground state related genes were down regulated, and ES cells could not be maintained the ground state pluripotency even in 2i medium. All of these results indicate Stat3 activation is required in ground state maintenance.

The differentiation and isolation of mouse embryonic stem cells toward hepatocytes using galactose-carrying substrata.

PubMed

Meng, Qingyuan; Haque, Amranul; Hexig, Bayar; Akaike, Toshihiro

2012-02-01

A simple culture system to achieve the differentiation of embryonic stem (ES) cells toward hepatocytes with high efficiency is crucial in providing a cell source for the medical application. In this study, we report the effect of a matrix-dependent enrichment of ES cell-derived hepatocytes using immobilized poly(N-p-vinylbenzyl-4-O-β-D-galactopyranosyl-D-gluconamide) (PVLA) with E-cadherin-IgG Fc (E-cad-Fc) as a galactose-carrying substratum. PVLA and E-cad-Fc were confirmed to be stably co-adsorbed onto polystyrene surface by quartz crystal microbalance (QCM). We showed that the E-cad-Fc/PVLA hybrid substratum was efficient in culturing primary hepatocytes and maintaining liver functions, on which the undifferentiated ES cells also maintained high proliferative capability. Furthermore, ES cell-derived hepatocytes on this hybrid matrix expressed elevated level of liver specific genes and functions together with early expression of definitive hepatocyte marker, asialoglycoprotein receptor (ASGPR). Finally, we isolated a high percentage of cells (about 60%) with ASGPR expression after re-seeding onto PVLA-coated surface, and observed the elimination of the poorly differentiated cells (Gata6(+) and Sox17(+)) and the ones toward another cell lineage (brachyury(+) and Pdx1(+)). The system uses a glycopolymer as an extracellular substratum for isolation and enrichment of ES cell-derived hepatocytes with adequate homogeneity and functionality. Copyright © 2011 Elsevier Ltd. All rights reserved.

A role for autophagic protein beclin 1 early in lymphocyte development.

PubMed

Arsov, Ivica; Adebayo, Adeola; Kucerova-Levisohn, Martina; Haye, Joanna; MacNeil, Margaret; Papavasiliou, F Nina; Yue, Zhenyu; Ortiz, Benjamin D

2011-02-15

Autophagy is a highly regulated and evolutionarily conserved process of cellular self-digestion. Recent evidence suggests that this process plays an important role in regulating T cell homeostasis. In this study, we used Rag1(-/-) (recombination activating gene 1(-/-)) blastocyst complementation and in vitro embryonic stem cell differentiation to address the role of Beclin 1, one of the key autophagic proteins, in lymphocyte development. Beclin 1-deficient Rag1(-/-) chimeras displayed a dramatic reduction in thymic cellularity compared with control mice. Using embryonic stem cell differentiation in vitro, we found that the inability to maintain normal thymic cellularity is likely caused by impaired maintenance of thymocyte progenitors. Interestingly, despite drastically reduced thymocyte numbers, the peripheral T cell compartment of Beclin 1-deficient Rag1(-/-) chimeras is largely normal. Peripheral T cells displayed normal in vitro proliferation despite significantly reduced numbers of autophagosomes. In addition, these chimeras had greatly reduced numbers of early B cells in the bone marrow compared with controls. However, the peripheral B cell compartment was not dramatically impacted by Beclin 1 deficiency. Collectively, our results suggest that Beclin 1 is required for maintenance of undifferentiated/early lymphocyte progenitor populations. In contrast, Beclin 1 is largely dispensable for the initial generation and function of the peripheral T and B cell compartments. This indicates that normal lymphocyte development involves Beclin 1-dependent, early-stage and distinct, Beclin 1-independent, late-stage processes.

Undifferentiated embryonic stem cells express ionotropic glutamate receptor mRNAs

PubMed Central

Pachernegg, Svenja; Joshi, Illah; Muth-Köhne, Elke; Pahl, Steffen; Münster, Yvonne; Terhag, Jan; Karus, Michael; Werner, Markus; Ma-Högemeier, Zhan-Lu; Körber, Christoph; Grunwald, Thomas; Faissner, Andreas; Wiese, Stefan; Hollmann, Michael

2013-01-01

Ionotropic glutamate receptors (iGluRs) do not only mediate the majority of excitatory neurotransmission in the vertebrate CNS, but also modulate pre- and postnatal neurogenesis. Most of the studies on the developmental role of iGluRs are performed on neural progenitors and neural stem cells (NSCs). We took a step back in our study by examining the role of iGluRs in the earliest possible cell type, embryonic stem cells (ESCs), by looking at the mRNA expression of the major iGluR subfamilies in undifferentiated mouse ESCs. For that, we used two distinct murine ES cell lines, 46C ESCs and J1 ESCs. Regarding 46C ESCs, we found transcripts of kainate receptors (KARs) (GluK2 to GluK5), AMPA receptors (AMPARs) (GluA1, GluA3, and GluA4), and NMDA receptors (NMDARs) (GluN1, and GluN2A to GluN2D). Analysis of 46C-derived cells of later developmental stages, namely neuroepithelial precursor cells (NEPs) and NSCs, revealed that the mRNA expression of KARs is significantly upregulated in NEPs and, subsequently, downregulated in NSCs. However, we could not detect any protein expression of any of the KAR subunits present on the mRNA level either in ESCs, NEPs, or NSCs. Regarding AMPARs and NMDARs, GluN2A is weakly expressed at the protein level only in NSCs. Matching our findings for iGluRs, all three cell types were found to weakly express pre- and postsynaptic markers of glutamatergic synapses only at the mRNA level. Finally, we performed patch-clamp recordings of 46C ESCs and could not detect any current upon iGluR agonist application. Similar to 46C ESCs, J1 ESCs express KARs (GluK2 to GluK5), AMPARs (GluA3), and NMDARs (GluN1, and GluN2A to GluN2D) at the mRNA level, but these transcripts are not translated into receptor proteins either. Thus, we conclude that ESCs do not contain functional iGluRs, although they do express an almost complete set of iGluR subunit mRNAs. PMID:24348335

Comprehensive Identification of Krüppel-Like Factor Family Members Contributing to the Self-Renewal of Mouse Embryonic Stem Cells and Cellular Reprogramming.

PubMed

Jeon, Hyojung; Waku, Tsuyoshi; Azami, Takuya; Khoa, Le Tran Phuc; Yanagisawa, Jun; Takahashi, Satoru; Ema, Masatsugu

2016-01-01

Pluripotency is maintained in mouse embryonic stem (ES) cells and is induced from somatic cells by the activation of appropriate transcriptional regulatory networks. Krüppel-like factor gene family members, such as Klf2, Klf4 and Klf5, have important roles in maintaining the undifferentiated state of mouse ES cells as well as in cellular reprogramming, yet it is not known whether other Klf family members exert self-renewal and reprogramming functions when overexpressed. In this study, we examined whether overexpression of any representative Klf family member, such as Klf1-Klf10, would be sufficient for the self-renewal of mouse ES cells. We found that only Klf2, Klf4, and Klf5 produced leukemia inhibitory factor (LIF)-independent self-renewal, although most KLF proteins, if not all, have the ability to occupy the regulatory regions of Nanog, a critical Klf target gene. We also examined whether overexpression of any of Klf1-Klf10 would be sufficient to convert epiblast stem cells into a naïve pluripotent state and found that Klf5 had such reprogramming ability, in addition to Klf2 and Klf4. We also delineated the functional domains of the Klf2 protein for LIF-independent self-renewal and reprogramming. Interestingly, we found that both the N-terminal transcriptional activation and C-terminal zinc finger domains were indispensable for this activity. Taken together, our comprehensive analysis provides new insight into the contribution of Klf family members to mouse ES self-renewal and cellular reprogramming.

Effect of ROCK inhibitor Y-27632 on normal and variant human embryonic stem cells (hESCs) in vitro: its benefits in hESC expansion.

PubMed

Gauthaman, Kalamegam; Fong, Chui-Yee; Bongso, Ariff

2010-03-01

The Rho associated coiled coil protein kinase (ROCK) dependent signaling pathway plays an important role in numerous physiological functions such as cell proliferation, adhesion, migration and inflammation. Human embryonic stem cells (hESCs) undergo differentiation and poor survival after single cell dissociation in culture thus limiting their expansion for cell based therapies. We evaluated the role of the selective ROCK inhibitor Y-27632 on hESC colonies and disassociated single hESCs from two different hESC lines. Karyotypically normal hESCs (HES3) and variant hESCs (BG01V) were treated with Y-27632 at 5, 10 and 20 muM concentrations for 72 h and its effects on hESC self renewal, colony morphology, cell cycle and pluripotency were evaluated. Increased cell proliferation of both HES3 and BG01V were observed for all three concentrations compared to untreated controls following passaging of cell clusters or dissociated single cells and some of these increases were statistically significant. Cell cycle assay demonstrated normal cell cycle progression with no peaks evident of apoptosis. No morphological differentiation was evident following treatment with the highest concentration of Y-27632 (20 muM) and the stemness related genes continued to be highly expressed in both HES3 and BG01V cells compared to untreated controls. The results confirmed that Y-27632 is a useful agent that aids in the expansion of undifferentiated hESC numbers for downstream applications in regenerative medicine.

Germ cell tumour growth patterns originating from clear cell carcinomas of the ovary and endometrium: a comparative immunohistochemical study favouring their origin from somatic stem cells.

PubMed

Nogales, Francisco F; Prat, Jaime; Schuldt, Maolly; Cruz-Viruel, Nelly; Kaur, Baljeet; D'Angelo, Emanuela; Matias-Guiu, Xavier; Vidal, August; McCluggage, W Glenn; Oosterhuis, J Wolter

2018-03-01

To report a series of 11 ovarian and one endometrial neoplasm in elderly patients with mixed clear cell tumour and germ cell tumour (GCT) components, to compare their immunohistochemical profiles and demonstrate a putative stem cell population. The clear cell tumours included 11 clear cell carcinomas (CCC) and one borderline clear cell tumour, while the GCT always included glandular yolk sac tumour (YST). In four cases, there were also foci of teratoma with immature neuroepithelial and endodermal tissues and undifferentiated areas showing true embryoids. To distinguish between the clear cell and YST components, the following antibodies were used: HNF1-β, napsin-A, cytokeratin 7 (CK7), PAX8, EMA, AFP, SALL4, villin, glypican-3 (GPC-3), GATA3, HepPar-1, OCT4, CDX2, CD30 and SOX2. HNF1-β, CK7, EMA and GPC-3 were often expressed in both components. Other markers had higher specificity for each cellular lineage; napsin-A and PAX8 were expressed only in CCC, while SALL4, villin, AFP and HepPar-1 were positive in the glandular YST component but negative in the clear cell component. OCT4 expression occurred in six of 10 cases and consistently in teratoma (four of four). There is considerable immunophenotypical overlap between the two components in these mixed neoplasms, and a panel of markers should be used to facilitate the distinction. We propose that OCT4-expressing somatic cancer cells differentiate into GCT and represent spontaneously induced pluripotent stem cells, possibly conditioned by age-related epigenetic factors. These neoplasms have features of prepubertal type GCT showing lack of 12p gain, preponderance of YST and coexistence with immature neuroectoderm. However, there may also be undifferentiated stem cell areas with embryoid bodies, of the type seen in postpubertal testicular GCT, but lacking a complete embryonal carcinoma immunophenotype. © 2017 John Wiley & Sons Ltd.

Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro.

PubMed

Cong, Shan; Cao, Guifang; Liu, Dongjun

2014-12-01

To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1-5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic fibroblast feeder layers of mouse and bovine embryonic fibroblast at different ratios and sources including mouse fibroblast cell lines. The bovine embryonic stem cell-like cells generated in our study displayed typical stem cell morphology and expressed specific markers such as OCT4, stage-specific embryonic antigen 1 and 4, alkaline phosphatase, SOX2, and NANOG mRNA levels. When feeder layers and cell growth factors were removed, the bovine embryonic stem cell-like cells formed embryoid bodies in a suspension culture. Furthermore, we compared the expression of the pluripotent markers during bovine embryonic stem cell-like cell in culture on mixed embryonic fibroblast feeder layers, including mouse fibroblast cell lines feeder layers and mouse embryonic fibroblast feeder layers by real-time quantitative polymerase chain reaction. Results suggested that mixed embryonic fibroblast and sources including mouse fibroblast cell lines feeder layers were more suitable for long-term culture and growth of bovine embryonic stem cell-like cells than mouse embryonic fibroblast feeder layers. The findings may provide useful experimental data for the establishment of an appropriate culture system for bovine embryonic stem cell lines.

Protein content and methyl donors in maternal diet interact to influence the proliferation rate and cell fate of neural stem cells in rat hippocampus.

PubMed

Amarger, Valérie; Lecouillard, Angèle; Ancellet, Laure; Grit, Isabelle; Castellano, Blandine; Hulin, Philippe; Parnet, Patricia

2014-10-14

Maternal diet during pregnancy and early postnatal life influences the setting up of normal physiological functions in the offspring. Epigenetic mechanisms regulate cell differentiation during embryonic development and may mediate gene/environment interactions. We showed here that high methyl donors associated with normal protein content in maternal diet increased the in vitro proliferation rate of neural stem/progenitor cells isolated from rat E19 fetuses. Gene expression on whole hippocampi at weaning confirmed this effect as evidenced by the higher expression of the Nestin and Igf2 genes, suggesting a higher amount of undifferentiated precursor cells. Additionally, protein restriction reduced the expression of the insulin receptor gene, which is essential to the action of IGFII. Inhibition of DNA methylation in neural stem/progenitor cells in vitro increased the expression of the astrocyte-specific Gfap gene and decreased the expression of the neuron-specific Dcx gene, suggesting an impact on cell differentiation. Our data suggest a complex interaction between methyl donors and protein content in maternal diet that influence the expression of major growth factors and their receptors and therefore impact the proliferation and differentiation capacities of neural stem cells, either through external hormone signals or internal genomic regulation.

Cellular genetic therapy.

PubMed

Del Vecchio, F; Filareto, A; Spitalieri, P; Sangiuolo, F; Novelli, G

2005-01-01

Cellular genetic therapy is the ultimate frontier for those pathologies that are consequent to a specific nonfunctional cellular type. A viable cure for there kinds of diseases is the replacement of sick cells with healthy ones, which can be obtained from the same patient or a different donor. In fact, structures can be corrected and strengthened with the introduction of undifferentiated cells within specific target tissues, where they will specialize into the desired cellular types. Furthermore, consequent to the recent results obtained with the transdifferentiation experiments, a process that allows the in vitro differentiation of embryonic and adult stem cells, it has also became clear that many advantages may be obtained from the use of stem cells to produce drugs, vaccines, and therapeutic molecules. Since stem cells can sustain lineage potentials, the capacity for differentiation, and better tolerance for the introduction of exogenous genes, they are also considered as feasible therapeutic vehicles for gene therapy. In fact, it is strongly believed that the combination of cellular genetic and gene therapy approaches will definitely allow the development of new therapeutic strategies as well as the production of totipotent cell lines to be used as experimental models for the cure of genetic disorders.

Stem cells in clinical trials for treatment of retinal degeneration.

PubMed

Klassen, Henry

2016-01-01

After decades of basic science research involving the testing of regenerative strategies in animal models of retinal degenerative diseases, a number of clinical trials are now underway, with additional trials set to begin shortly. These efforts will evaluate the safety and preliminary efficacy of cell-based products in the eyes of patients with a number of retinal conditions, notably including age-related macular degeneration, retinitis pigmentosa and Stargardt's disease. This review considers the scientific work and early trials with fetal cells and tissues that set the stage for the current clinical investigatory work, as well the trials themselves, specifically those either now completed, underway or close to initiation. The cells of interest include retinal pigment epithelial cells derived from embryonic stem or induced pluripotent stem cells, undifferentiated neural or retinal progenitors or cells from the vascular/bone marrow compartment or umbilical cord tissue. Degenerative diseases of the retina represent a popular target for emerging cell-based therapeutics and initial data from early stage clinical trials suggest that short-term safety objectives can be met in at least some cases. The question of efficacy will require additional time and testing to be adequately resolved.

Development of experimental tumors formed by mouse and human embryonic stem and teratocarcinoma cells after subcutaneous and intraperitoneal transplantations into immunodeficient and immunocompetent mice.

PubMed

Gordeeva, O F; Nikonova, T M

2013-01-01

Pluripotent stem cells represent an attractive cell source for regenerative medicine. However, the risk of teratoma formation after transplantation restricts their clinical application. Therefore, to adequately evaluate the potential risk of tumorigenicity after cell transplantation into human tissues, effective animal transplantation assays need to be developed. We performed a multiparameter (cell number, transplantation site, cell type, host) comparative analysis of the efficiency of tumor development after transplantation of mouse and human embryonic stem (ES) cells and their malignant counterparts, teratocarcinoma (EC) cells, into animal recipients and revealed several key correlations. We found that the efficiency of tumor growth was higher after intraperitoneal than after subcutaneous transplantations of all cell lines studied. The minimal cell numbers sufficient for tumor growth in immunodeficient nude mice were 100-fold lower for intraperitoneal than for subcutaneous transplantations of mouse and human ES cells (10(3) vs. 10(5) and 10(4) vs. 10(6), respectively). Moreover, mouse ES and EC cells formed tumors in immunodeficient and immunocompetent mice more effectively than human ES and EC cells. After intraperitoneal transplantation of 10(3), 10(4), and 10(5) mouse ES cells, teratomas developed in 83%, 100%, and 100% of nude mice, whereas after human ES cell transplantation, teratomas developed in 0%, 17%, and 60%, respectively. In addition, malignant mouse and human EC cells initiated tumor growth after intraperitoneal transplantation significantly faster and more effectively than ES cells. Mouse and human ES cells formed different types of teratomas containing derivatives of three germ layers but different numbers of undifferentiated cells. ES cell-like sublines with differentiation potential similar to the parental cell line were recloned only from mouse, but not from human, ES cell teratomas. These findings provide new information about the possibility and efficiency of tumor growth after transplantation of pluripotent stem cells. This information allows one to predict and possibly prevent the possible risks of tumorigenicity that could arise from stem cell therapeutics.

A Novel In Vitro Method for Detecting Undifferentiated Human Pluripotent Stem Cells as Impurities in Cell Therapy Products Using a Highly Efficient Culture System

PubMed Central

Tano, Keiko; Yasuda, Satoshi; Kuroda, Takuya; Saito, Hirohisa; Umezawa, Akihiro; Sato, Yoji

2014-01-01

Innovative applications of cell therapy products (CTPs) derived from human pluripotent stem cells (hPSCs) in regenerative medicine are currently being developed. The presence of residual undifferentiated hPSCs in CTPs is a quality concern associated with tumorigencity. However, no simple in vitro method for direct detection of undifferentiated hPSCs that contaminate CTPs has been developed. Here, we show a novel approach for direct and sensitive detection of a trace amount of undifferentiated human induced pluripotent stem cells (hiPSCs) using a highly efficient amplification method in combination with laminin-521 and Essential 8 medium. Essential 8 medium better facilitated the growth of hiPSCs dissociated into single cells on laminin-521 than in mTeSR1 medium. hiPSCs cultured on laminin-521 in Essential 8 medium were maintained in an undifferentiated state and they maintained the ability to differentiate into various cell types. Essential 8 medium allowed robust hiPSC proliferation plated on laminin-521 at low cell density, whereas mTeSR1 did not enhance the cell growth. The highly efficient culture system using laminin-521 and Essential 8 medium detected hiPSCs spiked into primary human mesenchymal stem cells (hMSCs) or human neurons at the ratio of 0.001%–0.01% as formed colonies. Moreover, this assay method was demonstrated to detect residual undifferentiated hiPSCs in cell preparations during the process of hMSC differentiation from hiPSCs. These results indicate that our highly efficient amplification system using a combination of laminin-521 and Essential 8 medium is able to detect a trace amount of undifferentiated hPSCs contained as impurities in CTPs and would contribute to quality assessment of hPSC-derived CTPs during the manufacturing process. PMID:25347300

The business of human embryonic stem cell research and an international analysis of relevant laws.

PubMed

De Trizio, Ella; Brennan, Christopher S

2004-01-01

Few sciences have held out such therapeutic promise and correspondingly stirred so much controversy in countries throughout the world as the developing science surrounding human embryonic stem cells. Since the first reported development of several lines of human embryonic stem cells in 1988, many governments around the world have attempted to address the thorny ethical issues raised by human embryonic stem cell research by the passage of laws. In some cases these laws have directly regulated governmental funding of the science; in other cases they have created a legal environment that has either encouraged or discouraged both governmental and private funding of the science. This article first differentiates human embryonic stem cells from other types of stem cells and frames the ethical controversy surrounding human embryonic stem cell research, then surveys laws governing human embryonic stem cell research in various scientifically advanced countries located throughout the Pacific Rim, Europe and North America and explains the impact these laws have had on governmental and private funding of human embryonic stem cell research.

Stem cells for regenerative medicine: advances in the engineering of tissues and organs

NASA Astrophysics Data System (ADS)

Ringe, Jochen; Kaps, Christian; Burmester, Gerd-Rüdiger; Sittinger, Michael

2002-07-01

The adult bone marrow stroma contains a subset of nonhematopoietic cells referred to as mesenchymal stem or mesenchymal progenitor cells (MSC). These cells have the capacity to undergo extensive replication in an undifferentiated state ex vivo. In addition, MSC have the potential to develop either in vitro or in vivo into distinct mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma, which suggest these cells as an attractive cell source for tissue engineering approaches. The interest in modern biological technologies such as tissue engineering has dramatically increased since it is feasible to isolate living, healthy cells from the body, expand them under cell culture conditions, combine them with biocompatible carrier materials and retransplant them into patients. Therefore, tissue engineering gives the opportunity to generate living substitutes for tissues and organs, which may overcome the drawbacks of classical tissue reconstruction: lacking quality and quantity of autologous grafts, immunogenicity of allogenic grafts and loosening of alloplastic implants. Due to the prerequisite for tissue engineering to ensure a sufficient number of tissue specific cells without donor site morbidity, much attention has been drawn to multipotential progenitor cells such as embryonic stem cells, periosteal cells and mesenchymal stem cells. In this report we review the state of the art in tissue engineering with mesenchymal stem and mesenchymal progenitor cells with emphasis on bone and cartilage reconstruction. Furthermore, several issues of importance, especially with regard to the clinical application of mesenchymal stem cells, are discussed.

p75 neurotrophin receptor is involved in proliferation of undifferentiated mouse embryonic stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moscatelli, Ilana; Pierantozzi, Enrico; Camaioni, Antonella

2009-11-01

Neurotrophins and their receptors are known to play a role in the proliferation and survival of many different cell types of neuronal and non-neuronal lineages. In addition, there is much evidence in the literature showing that the p75 neurotrophin receptor (p75{sup NTR}), alone or in association with members of the family of Trk receptors, is expressed in a wide variety of stem cells, although its role in such cells has not been completely elucidated. In the present work we have investigated the expression of p75{sup NTR} and Trks in totipotent and pluripotent cells, the mouse pre-implantation embryo and embryonic stemmore » and germ cells (ES and EG cells). p75{sup NTR} and TrkA can be first detected in the blastocyst from which ES cell lines are derived. Mouse ES cells retain p75{sup NTR}/TrkA expression. Nerve growth factor is the only neurotrophin able to stimulate ES cell growth in culture, without affecting the expression of stem cell markers, alkaline phosphatase, Oct4 and Nanog. Such proliferation effect was blocked by antagonizing either p75{sup NTR} or TrkA. Interestingly, immunoreactivity to anti-p75{sup NTR} antibodies is lost upon ES cell differentiation. The expression pattern of neurotrophin receptors in murine ES cells differs from human ES cells, that only express TrkB and C, and do not respond to NGF. In this paper we also show that, while primordial germ cells (PGC) do not express p75{sup NTR}, when they are made to revert to an ES-like phenotype, becoming EG cells, expression of p75{sup NTR} is turned on.« less

Altered expression of epithelial mesenchymal transition and pluripotent associated markers by sex steroid hormones in human embryonic stem cells.

PubMed

Jeon, So-Ye; Hwang, Kyung-A; Kim, Cho-Won; Jeung, Eui-Bae; Choi, Kyung-Chul

2017-07-01

Embryonic stem (ES) cells are pluripotent stem cells derived from a developmental stage of pre‑implanted embryos. The present study investigated the effect of female sex steroid hormones on the characteristics of human ES cells by using a feeder‑free culture protocol. In a feeder‑free condition without sex hormones, human ES cells assumed the form of tightly packed cells that grow in a monolayer. The cells had clean and defined edges with no evidence of differentiation and expressed several markers specific for undifferentiated ES cells including POU class 5 homeobox 1 (POU5F1), sex determining region Y‑box 2 (SOX2) and NANOG homeobox (NANOG). It was then investigated if female sex steroid hormones including 17β‑estradiol (E2) and progesterone (P4) altered the protein expression of epithelial-mesenchymal transition (EMT) associated markers in addition to pluripotency markers including POU5F1, SOX2 and NANOG in human ES cells. The protein expression levels of N‑cadherin, Snail and Slug were increased while E‑cadherin expression was decreased by treatment of E2 or P4, and the expression levels of POU5F1, SOX2 and NANOG were decreased by the treatment of E2 or P4. When E2 and P4 were treated in combination with an estrogen receptor inhibitor (ICI 182,780) and progesterone receptor inhibitor (RU486) respectively, their effects on EMT and pluripotency of ES cells were restored to control levels. The results suggested that E2 and P4 may regulate EMT and pluripotency of human ES cells by mediating their receptors. The present study may aid in the understanding of the role of sex steroid hormones in the cellular biology of human ES cells.

Characterization of tumor cells and stem cells by differential nuclear methylation imaging

NASA Astrophysics Data System (ADS)

Tajbakhsh, Jian; Wawrowsky, Kolja A.; Gertych, Arkadiusz; Bar-Nur, Ori; Vishnevsky, Eugene; Lindsley, Erik H.; Farkas, Daniel L.

2008-02-01

DNA methylation plays a key role in cellular differentiation. Aberrant global methylation patterns are associated with several cancer types, as a result of changes in long-term activation status of up to 50% of genes, including oncogenes and tumor-suppressor genes, which are regulated by methylation and demethylation of promoter region CpG dinucleotides (CpG islands). Furthermore, DNA methylation also occurs in nonisland CpG sites (> 95% of the genome), present once per 80 dinucleotides on average. Nuclear DNA methylation increases during the course of cellular differentiation while cancer cells usually show a net loss in methylation. Given the large dynamic range in DNA methylation load, the methylation pattern of a cell can provide a valuable distinction as to its status during differentiation versus the disease state. By applying immunofluorescence, confocal microscopy and 3D image analysis we assessed the potential of differential nuclear distribution of methylated DNA to be utilized as a biomarker to characterize cells during development and when diseased. There are two major fields that may immediately benefit from this development: (1) the search for factors that contribute to pluripotency and cell fate in human embryonic stem cell expansion and differentiation, and (2) the characterization of tumor cells with regard to their heterogeneity in molecular composition and behavior. We performed topological analysis of the distribution of methylated CpG-sites (MeC) versus heterochromatin. This innovative approach revealed significant differences in colocalization patterns of MeC and heterochromatin-derived signals between undifferentiated and differentiated human embryonic stem cells, as well as untreated AtT20 mouse pituitary tumor cells compared to a subpopulation of these cells treated with 5-azacytidine for 48 hours.

Two sides of the same coin? Unraveling subtle differences between human embryonic and induced pluripotent stem cells by Raman spectroscopy.

PubMed

Parrotta, Elvira; De Angelis, Maria Teresa; Scalise, Stefania; Candeloro, Patrizio; Santamaria, Gianluca; Paonessa, Mariagrazia; Coluccio, Maria Laura; Perozziello, Gerardo; De Vitis, Stefania; Sgura, Antonella; Coluzzi, Elisa; Mollace, Vincenzo; Di Fabrizio, Enzo Mario; Cuda, Giovanni

2017-11-28

Human pluripotent stem cells, including embryonic stem cells and induced pluripotent stem cells, hold enormous promise for many biomedical applications, such as regenerative medicine, drug testing, and disease modeling. Although induced pluripotent stem cells resemble embryonic stem cells both morphologically and functionally, the extent to which these cell lines are truly equivalent, from a molecular point of view, remains controversial. Principal component analysis and K-means cluster analysis of collected Raman spectroscopy data were used for a comparative study of the biochemical fingerprint of human induced pluripotent stem cells and human embryonic stem cells. The Raman spectra analysis results were further validated by conventional biological assays. Raman spectra analysis revealed that the major difference between human embryonic stem cells and induced pluripotent stem cells is due to the nucleic acid content, as shown by the strong positive peaks at 785, 1098, 1334, 1371, 1484, and 1575 cm -1 , which is enriched in human induced pluripotent stem cells. Here, we report a nonbiological approach to discriminate human induced pluripotent stem cells from their native embryonic stem cell counterparts.

Optimization of culture conditions to support long-term self-renewal of buffalo (Bubalus bubalis) embryonic stem cell-like cells.

PubMed

Sharma, Ruchi; George, Aman; Kamble, Nitin Manchindra; Singh, Karn Pratap; Chauhan, Manmohan Singh; Singla, Suresh Kumar; Manik, Radhey Sham; Palta, Prabhat

2011-12-01

A culture system capable of sustaining self-renewal of buffalo embryonic stem (ES) cell-like cells in an undifferentiated state over a long period of time was developed. Inner cell masses were seeded on KO-DMEM+15% KO-serum replacer on buffalo fetal fibroblast feeder layer. Supplementation of culture medium with 5 ng/mL FGF-2 and 1000 IU/mL mLIF gave the highest (p<0.05) rate of primary colony formation. The ES cell-like cells' colony survival rate and increase in colony size were highest (p<0.05) following supplementation with FGF-2 and LIF compared to other groups examined. FGF-2 supplementation affected the quantitative expression of NANOG, SOX-2, ACTIVIN A, BMP 4, and TGFβ1, but not OCT4 and GREMLIN. Supplementation with SU5402, an FGFR inhibitor (≥20 μM) increased (p<0.05) the percentage of colonies that differentiated. FGFR1-3 and ERK1, K-RAS, E-RAS, and SHP-2, key signaling intermediates of FGF signaling, were detected in ES cell-like cells. Under culture conditions described, three ES cell lines were derived that, to date, have been maintained for 135, 95, and 85 passages for over 27, 19, and 17 months, respectively, whereas under other conditions examined, ES cell-like cells did not survive beyond passage 10. The ES cell-like cells were regularly monitored for expression of pluripotency markers and their potency to form embryoid bodies.

Evaluation of human embryonic stem cells and their differentiated fibroblastic progenies as cellular models for in vitro genotoxicity screening.

PubMed

Vinoth, Kumar Jayaseelan; Manikandan, Jayapal; Sethu, Swaminathan; Balakrishnan, Lakshmidevi; Heng, Alexis; Lu, Kai; Hande, Manoor Prakash; Cao, Tong

2014-08-20

This study evaluated human embryonic stem cells (hESC) and their differentiated fibroblastic progenies as cellular models for genotoxicity screening. The DNA damage response of hESCs and their differentiated fibroblastic progenies were compared to a fibroblastic cell line (HEPM, CRL1486) and primary cultures of peripheral blood lymphocytes (PBL), upon exposure to Mitomycin C, gamma irradiation and H2O2. It was demonstrated that hESC-derived fibroblastic progenies (H1F) displayed significantly higher chromosomal aberrations, micronuclei formation and double strand break (DSB) formation, as compared to undifferentiated hESC upon exposure to genotoxic stress. Nevertheless, H1F cell types displayed comparable sensitivities to genotoxic challenge as HEPM and PBL, both of which are representative of somatic cell types commonly used for genotoxicity screening. Subsequently, transcriptomic and pathways analysis identified differential expression of critical genes involved in cell death and DNA damage response upon exposure to gamma irradiation. The results thus demonstrate that hESC-derived fibroblastic progenies are as sensitive as commonly-used somatic cell types for genotoxicity screening. Moreover, hESCs have additional advantages, such as their genetic normality compared to immortalized cell lines, as well as their amenability to scale-up for producing large, standardized quantities of cells for genotoxicity screening on an industrial scale, something which can never be achieved with primary cell cultures. Copyright © 2014. Published by Elsevier B.V.

Cripto-1 Ablation Disrupts Alveolar Development in the Mouse Mammary Gland through a Progesterone Receptor–Mediated Pathway

PubMed Central

Klauzinska, Malgorzata; McCurdy, David; Rangel, Maria Cristina; Vaidyanath, Arun; Castro, Nadia P.; Shen, Michael M.; Gonzales, Monica; Bertolette, Daniel; Bianco, Caterina; Callahan, Robert; Salomon, David S.; Raafat, Ahmed

2016-01-01

Cripto-1, a member of the epidermal growth factor–Cripto-1/FRL-1/Cryptic family, is critical for early embryonic development. Together with its ligand Nodal, Cripto-1 has been found to be associated with the undifferentiated status of mouse and human embryonic stem cells. Several studies have clearly shown that Cripto-1 is involved in regulating branching morphogenesis and epithelial-mesenchymal transition of the mammary gland both in vitro and in vivo and together with the cofactor GRP78 is critical for the maintenance of mammary stem cells ex vivo. Our previous studies showed that mammary-specific overexpression of human Cripto-1 exhibited dramatic morphological alterations in nulliparous mice mammary glands. The present study shows a novel mechanism for Cripto-1 regulation of mammary gland development through direct effects on progesterone receptor expression and pathways regulated by progesterone in the mammary gland. We demonstrate a strict temporal regulation of mouse Cripto-1 (mCripto-1) expression that occurs during mammary gland development and a stage-specific function of mCripto-1 signaling during mammary gland development. Our data suggest that Cripto-1, like the progesterone receptor, is not required for the initial ductal growth but is essential for subsequent side branching and alveologenesis during the initial stages of pregnancy. Dissection of the mechanism by which this occurs indicates that mCripto-1 activates receptor activator NF-κB/receptor activator NF-κB ligand, and NF-κB signaling pathways. PMID:26429739

Basic FGF Support of Human Embryonic Stem Cell Self-Renewal

PubMed Central

Levenstein, Mark E.; Ludwig, Tenneille E.; Xu, Ren-He; Llanas, Rachel A.; VanDenHeuvel-Kramer, Kaitlyn; Manning, Daisy; Thomson, James A.

2015-01-01

Human embryonic stem (ES) cells have most commonly been cultured in the presence of basic FGF (FGF2) either on fibroblast feeder layers or in fibroblast-conditioned medium. Recently, it has been reported that elevated concentrations of FGF2 permit the culture of human ES cells in the absence of fibroblasts or fibroblast-conditioned medium. Here we compare the ability of unconditioned medium (UM) supplemented with 4, 24, 40, 80, 100 and 250 ng/ml FGF2 to sustain low-density human ES cell cultures through multiple passages. In these stringent culture conditions, 4, 24, and 40 ng/ml FGF2 failed to sustain human ES cells through three passages, but 100 ng/ml sustained human ES cells with an effectiveness comparable to conditioned medium (CM). Two human ES cell lines (H1 and H9) were maintained for up to 164 population doublings (7 and 4 months) in UM supplemented with 100 ng/ml FGF2. After prolonged culture the cells formed teratomas when injected into SCID-beige mice, and expressed markers characteristic of undifferentiated human ES cells. We also demonstrate that FGF2 is degraded more rapidly in UM than in CM, partly explaining the need for higher concentrations of FGF2 in UM. These results further facilitate the large-scale, routine culture of human ES cells, and suggest that fibroblasts and fibroblast-conditioned medium sustain human ES cells in part by stabilizing FGF signaling above a critical threshold. PMID:16282444

Derivation of novel genetically diverse human embryonic stem cell lines.

PubMed

Stefanova, Valentina T; Grifo, James A; Hansis, Christoph

2012-06-10

Human embryonic stem cells (hESCs) have the potential to revolutionize many biomedical fields ranging from basic research to disease modeling, regenerative medicine, drug discovery, and toxicity testing. A multitude of hESC lines have been derived worldwide since the first 5 lines by Thomson et al. 13 years ago, but many of these are poorly characterized, unavailable, or do not represent desired traits, thus making them unsuitable for application purposes. In order to provide the scientific community with better options, we have derived 12 new hESC lines at New York University from discarded genetically normal and abnormal embryos using the latest techniques. We examined the genetic status of the NYUES lines in detail as well as their molecular and cellular features and DNA fingerprinting profile. Furthermore, we differentiated our hESCs into the tissues most affected by a specific condition or into clinically desired cell types. To our knowledge, a number of characteristics of our hESCs have not been previously reported, for example, mutation for alpha thalassemia X-linked mental retardation syndrome, linkage to conditions with a genetic component such as asthma or poor sperm morphology, and novel combinations of ethnic backgrounds. Importantly, all of our undifferentiated euploid female lines tested to date did not show X chromosome inactivation, believed to result in superior potency. We continue to derive new hESC lines and add them to the NIH registry and other registries. This should facilitate the use of our hESCs and lead to advancements for patient-benefitting applications.

Design and characterization of hybrid peptide sol-gel materials for the solid state induction of neuronal differentiation

NASA Astrophysics Data System (ADS)

Jedlicka, Sabrina S.

2007-12-01

Cell-based therapeutics are a rapidly growing area of research, with considerable promise in the treatment of neurological diseases. One of the primary limitations to neuronal cell-based devices is the necessity to maintain cells in an immature or undifferentiated state in culture prior to transplantation. In many cases, the undifferentiated cell does not express the desired characteristics for implantation. Biologically functional nanomaterials provide the ability to manipulate the direct extracellular environment surrounding cells; influencing their fate and differentiation path. The ability to engineer the interface between the cells and culture materials provides a repeatable, stable means of directing cells down a specific growth path determined by endogenous signaling pathways. This materials approach to cellular engineering can limit the need for added exogenous growth factors, "feeder" layers, or animal sera, in addition to creating a homogenous cell population for transplantation. In this work, hybrid peptide ormosil materials were developed; designed to mimic the developing mammalian brain during corticogenesis. These materials have been developed to enhance the GABAergic phenotype of P19 embryonic carcinoma cells and immature immortalized neurons. The ability to develop a homogenous, directed cell population has implications in stem cell research, regenerative medicine, cell-based devices and biosensing technology.

Effect of Antibiotics against Mycoplasma sp. on Human Embryonic Stem Cells Undifferentiated Status, Pluripotency, Cell Viability and Growth

PubMed Central

Romorini, Leonardo; Riva, Diego Ariel; Blüguermann, Carolina; Videla Richardson, Guillermo Agustin; Scassa, Maria Elida; Sevlever, Gustavo Emilio; Miriuka, Santiago Gabriel

2013-01-01

Human embryonic stem cells (hESCs) are self-renewing pluripotent cells that can differentiate into specialized cells and hold great promise as models for human development and disease studies, cell-replacement therapies, drug discovery and in vitro cytotoxicity tests. The culture and differentiation of these cells are both complex and expensive, so it is essential to extreme aseptic conditions. hESCs are susceptible to Mycoplasma sp. infection, which is hard to detect and alters stem cell-associated properties. The purpose of this work was to evaluate the efficacy and cytotoxic effect of PlasmocinTM and ciprofloxacin (specific antibiotics used for Mycoplasma sp. eradication) on hESCs. Mycoplasma sp. infected HUES-5 884 (H5 884, stable hESCs H5-brachyury promoter-GFP line) cells were effectively cured with a 14 days PlasmocinTM 25 µg/ml treatment (curative treatment) while maintaining stemness characteristic features. Furthermore, cured H5 884 cells exhibit the same karyotype as the parental H5 line and expressed GFP, through up-regulation of brachyury promoter, at day 4 of differentiation onset. Moreover, H5 cells treated with ciprofloxacin 10 µg/ml for 14 days (mimic of curative treatment) and H5 and WA09 (H9) hESCs treated with PlasmocinTM 5 µg/ml (prophylactic treatment) for 5 passages retained hESCs features, as judged by the expression of stemness-related genes (TRA1-60, TRA1-81, SSEA-4, Oct-4, Nanog) at mRNA and protein levels. In addition, the presence of specific markers of the three germ layers (brachyury, Nkx2.5 and cTnT: mesoderm; AFP: endoderm; nestin and Pax-6: ectoderm) was verified in in vitro differentiated antibiotic-treated hESCs. In conclusion, we found that PlasmocinTM and ciprofloxacin do not affect hESCs stemness and pluripotency nor cell viability. However, curative treatments slightly diminished cell growth rate. This cytotoxic effect was reversible as cells regained normal growth rate upon antibiotic withdrawal. PMID:23936178

[Low expression of activin A in mouse and human embryonic teratocarcinoma cells].

PubMed

Gordeeva, O F

2014-01-01

TGFP3 family factors play an important role in regulating the balance of self-renewal and differentiation of mouse and human pluripotent stem and embryonic teratocarcinoma cells. The expression patterns of TGFbeta family signaling ligands and functional roles of these signaling pathways differ significantly in mouse and human embryonic stem cells, but the activity and functional role of these factors in mouse and human embryonic teratocarcinoma cells were not sufficiently investigated. Comparative quantitative real-time PCR analysis of the expression of TGF@[beta] family factors in mouse embryonic stem, embryonic germ, and embryonic teratocarcinoma cells showed that embryonic teratocarcinoma cells express lower ActivinA than pluripotent stem cells but similar levels of factors Nodal, Lefty 1, TGFbeta1, BMP4, and GDF3. In human nullipotent embryonic teratocarcinoma PA-1 cells, most factors of the TGFbeta family (ACTIVINA, NODAL, LEFTY 1, BMP4, and GDF3) are expressed at lower levels than in human embryonic stem cells: Thus, in mouse and human nullipotent teratocarcinoma cells, theexpression of ActivinA is significantly reduced com- pared ivith embryonic stem cells. Presumably, these differences may be associated with changes in the functional activity of the respective signaling pathways and deregulation of proliferative and antiproliferative mechanisms in embryonic teratocarcinoma cells.

A genetic platform to model sarcomagenesis from primary adult mesenchymal stem cells

PubMed Central

Guarnerio, Jlenia; Riccardi, Luisa; Taulli, Riccardo; Maeda, Takahiro; Wang, Guocan; Hobbs, Robin M.; Song, Min Sup; Sportoletti, Paolo; Bernardi, Rosa; Bronson, Roderick T.; Castillo-Martin, Mireia; Cordon-Cardo, Carlos; Lunardi, Andrea; Pandolfi, Pier Paolo

2015-01-01

The regulatory factors governing adult mesenchymal stem cells (MSCs) physiology and their tumorigenic potential are still largely unknown, which substantially delays the identification of effective therapeutic approaches for the treatment of aggressive and lethal form of MSC-derived mesenchymal tumors, such as undifferentiated sarcomas. Here we have developed a novel platform to screen and quickly identify genes and pathways responsible for adult MSCs transformation, modeled undifferentiated sarcoma in vivo, and, ultimately, tested the efficacy of targeting the identified oncopathways. Importantly, by taking advantage of this new platform, we demonstrate the key role of an aberrant LRF-DLK1-SOX9 pathway in the pathogenesis of undifferentiated sarcoma with important therapeutic implications. PMID:25614485

Morphological Analysis of Live Undifferentiated Cells Derived from Induced Pluripotent Stem Cells.

PubMed

Osawa, Yukihiko; Miyamoto, Tomoyuki; Ohno, Setsuyo; Ohno, Eiji

2018-01-01

Induced pluripotent stem (iPS) cells possess pluripotency and self-renewal ability. Therefore, iPS cells are expected to be useful in regenerative medicine. However, iPS cells form malignant immature teratomas after transplantation into animals, even after differentiation induction. It has been suggested that undifferentiated cells expressing Nanog that remain after differentiation induction are responsible for teratoma formation. Various methods of removing these undifferentiated cells have therefore been investigated, but few methods involve morphological approaches, which may induce less cell damage. In addition, for cells derived from iPS cells to be applied in regenerative medicine, they must be alive. However, detailed morphological analysis of live undifferentiated cells has not been performed. For the above reasons, we assessed the morphological features of live undifferentiated cells remaining after differentiation induction as a basic investigation into the clinical application of iPS cells. As a result, live undifferentiated cells remaining after differentiation induction exhibited a round or oval cytoplasm about 12 μm in diameter and a nucleus. They exhibited nucleo-cytoplasmic (N/C) ratio of about 60% and eccentric nuclei, and they possessed partially granule-like structures in the cytoplasm and prominent nucleoli. Although they were similar to iPS cells, they were smaller than live iPS cells. Furthermore, very small cells were present among undifferentiated cells after differentiation induction. These results suggest that the removal of undifferentiated cells may be possible using the morphological features of live iPS cells and undifferentiated cells after differentiation induction. In addition, this study supports safe regenerative medicine using iPS cells.

Cell-free extract from porcine induced pluripotent stem cells can affect porcine somatic cell nuclear reprogramming.

PubMed

No, Jin-Gu; Choi, Mi-Kyung; Kwon, Dae-Jin; Yoo, Jae Gyu; Yang, Byoung-Chul; Park, Jin-Ki; Kim, Dong-Hoon

2015-01-01

Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The Chariot(TM) reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3 lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear skin fibroblasts and cloned embryos.

Derivation of Stromal (Skeletal and Mesenchymal) Stem-Like Cells from Human Embryonic Stem Cells

PubMed Central

Harkness, Linda; Abdallah, Basem M.; Elsafadi, Mona; Al-Nbaheen, May S.; Aldahmash, Abdullah; Kassem, Moustapha

2012-01-01

Derivation of bone forming cells (osteoblasts) from human embryonic stem cells (hESCs) is a prerequisite for their use in clinical applications. However, there is no standard protocol for differentiating hESCs into osteoblastic cells. The aim of this study was to identify the emergence of a human stromal (mesenchymal and skeletal) stem cell (hMSC)-like population, known to be osteoblastic cell precursors and to test their osteoblastic differentiation capacity in ex vivo cultures and in vivo. We cultured hESCs in a feeder-free environment using serum replacement and as suspension aggregates (embryoid bodies; hEBs). Over a 20 day developmental period, the hEBs demonstrated increasing enrichment for cells expressing hMSC markers: CD29, CD44, CD63, CD56, CD71, CD73, CD105, CD106, and CD166 as revealed by immunohistochemical staining and flow cytometry (fluorescence-activated cell sorting) analysis. Ex vivo differentiation of hEBs using bone morphogenic protein 2 (BMP2) combined with standard osteoblast induction medium led to weak osteoblastic induction. Conversely, subcutaneous in vivo implantation of day 20 hEBs in immune deficient mice, mixed with hydroxyapatite/tricalcium phosphate (HA/TCP) as an osteoconductive scaffold, revealed bone and cartilage, and fibrous tissue elements after 8 weeks. These tissues were of human origin and there was no evidence of differentiation to nonmesodermal tissues. hEBs implanted in the absence of HA/TCP formed vacuolated tissue containing glandular, fibrous and muscle-like tissue elements. Conversely, implantation of undifferentiated hESCs resulted in the formation of a teratoma containing a mixture of endodermal, mesodermal, and ectodermal tissues. Our study demonstrates that hMSC-like cells can be obtained from hESCs and they can be induced to form skeletal tissues in vivo when combined with HA/TCP. These findings are relevant for tissue engineering and suggest that differentiated hEBs can provide an unlimited source for functional osteogenic cells. PMID:22612317

Podocalyxin Is a Glycoprotein Ligand of the Human Pluripotent Stem Cell-Specific Probe rBC2LCN

PubMed Central

Tateno, Hiroaki; Matsushima, Asako; Hiemori, Keiko; Onuma, Yasuko; Ito, Yuzuru; Hasehira, Kayo; Nishimura, Ken; Ohtaka, Manami; Takayasu, Satoko; Nakanishi, Mahito; Ikehara, Yuzuru; Nakanishi, Mio; Ohnuma, Kiyoshi; Chan, Techuan; Toyoda, Masashi; Akutsu, Hidenori; Umezawa, Akihiro; Asashima, Makoto

2013-01-01

In comprehensive glycome analysis with a high-density lectin microarray, we have previously shown that the recombinant N-terminal domain of the lectin BC2L-C from Burkholderia cenocepacia (rBC2LCN) binds exclusively to undifferentiated human induced pluripotent stem (iPS) cells and embryonic stem (ES) cells but not to differentiated somatic cells. Here we demonstrate that podocalyxin, a heavily glycosylated type 1 transmembrane protein, is a glycoprotein ligand of rBC2LCN on human iPS cells and ES cells. When analyzed by DNA microarray, podocalyxin was found to be highly expressed in both iPS cells and ES cells. Western and lectin blotting revealed that rBC2LCN binds to podocalyxin with a high molecular weight of more than 240 kDa in undifferentiated iPS cells of six different origins and four ES cell lines, but no binding was observed in either differentiated mouse feeder cells or somatic cells. The specific binding of rBC2LCN to podocalyxin prepared from a large set of iPS cells (138 types) and ES cells (15 types) was also confirmed using a high-throughput antibody-overlay lectin microarray. Alkaline digestion greatly reduced the binding of rBC2LCN to podocalyxin, indicating that the major glycan ligands of rBC2LCN are presented on O-glycans. Furthermore, rBC2LCN was found to exhibit significant affinity to a branched O-glycan comprising an H type 3 structure (Ka, 2.5 × 104 M−1) prepared from human 201B7 iPS cells, indicating that H type 3 is a most probable potential pluripotency marker. We conclude that podocalyxin is a glycoprotein ligand of rBC2LCN on human iPS cells and ES cells. PMID:23526252

78 FR 25091 - Submission for OMB Review; 30-Day Comment Request: Request for Human Embryonic Stem Cell Line To...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-29

...; 30-Day Comment Request: Request for Human Embryonic Stem Cell Line To Be Approved for Use in NIH... Embryonic Stem Cell Line to be Approved for Use in NIH-Funded Research, 0925-0601, Expiration Date 04/30... Information Collection: The form is used by applicants to request that human embryonic stem cell lines be...

The miR-290-295 cluster as multi-faceted players in mouse embryonic stem cells.

PubMed

Yuan, Kai; Ai, Wen-Bing; Wan, Lin-Yan; Tan, Xiao; Wu, Jiang-Feng

2017-01-01

Increasing evidence indicates that embryonic stem cell specific microRNAs (miRNAs) play an essential role in the early development of embryo. Among them, the miR-290-295 cluster is the most highly expressed in the mouse embryonic stem cells and involved in various biological processes. In this paper, we reviewed the research progress of the function of the miR-290-295 cluster in embryonic stem cells. The miR-290-295 cluster is involved in regulating embryonic stem cell pluripotency maintenance, self-renewal, and reprogramming somatic cells to an embryonic stem cell-like state. Moreover, the miR-290-295 cluster has a latent pro-survival function in embryonic stem cells and involved in tumourigenesis and senescence with a great significance. Elucidating the interaction between the miR-290-295 cluster and other modes of gene regulation will provide us new ideas on the biology of pluripotent stem cells. In the near future, the broad prospects of the miRNA cluster will be shown in the stem cell field, such as altering cell identities with high efficiency through the transient introduction of tissue-specific miRNA cluster.

Derivation and characterization of Chinese human embryonic stem cell line with high potential to differentiate into pancreatic and hepatic cells.

PubMed

Shi, Cheng; Shen, Huan; Jiang, Wei; Song, Zhi-Hua; Wang, Cheng-Yan; Wei, Li-Hui

2011-04-01

Human embryonic stem cells have prospective uses in regenerative medicine and drug screening. Every human embryonic stem cell line has its own genetic background, which determines its specific ability for differentiation as well as susceptibility to drugs. It is necessary to compile many human embryonic stem cell lines with various backgrounds for future clinical use, especially in China due to its large population. This study contributes to isolating new Chinese human embryonic stem cell lines with clarified directly differentiation ability. Donated embryos that exceeded clinical use in our in vitro fertilization-embryo transfer (IVF-ET) center were collected to establish human embryonic stem cells lines with informed consent. The classic growth factors of basic fibroblast growth factor (bFGF) and recombinant human leukaemia inhibitory factor (hLIF) for culturing embryonic stem cells were used to capture the stem cells from the plated embryos. Mechanical and enzymetic methods were used to propagate the newly established human embryonic stem cells line. The new cell line was checked for pluripotent characteristics with detecting the expression of stemness genes and observing spontaneous differentiation both in vitro and in vivo. Finally similar step-wise protocols from definitive endoderm to target specific cells were used to check the cell line's ability to directly differentiate into pancreatic and hepatic cells. We generated a new Chinese human embryonic stem cells line, CH1. This cell line showed the same characteristics as other reported Chinese human embryonic stem cells lines: normal morphology, karyotype and pluripotency in vitro and in vivo. The CH1 cells could be directly differentiated towards pancreatic and hepatic cells with equal efficiency compared to the H1 cell line. This newly established Chinese cell line, CH1, which is pluripotent and has high potential to differentiate into pancreatic and hepatic cells, will provide a useful tool for embryo development research, along with clinical treatments for diabetes and some hepatic diseases.

PI3 K/Akt/mTOR-mediated translational control regulates proliferation and differentiation of lineage-restricted RoSH stem cell lines

PubMed Central

Que, Jianwen; Lian, Qizhou; El Oakley, Reida M; Lim, Bing; Lim, Sai-Kiang

2007-01-01

Background We have previously derived highly similar lineage-restricted stem cell lines, RoSH and E-RoSH cell lines from mouse embryos and CD9hi SSEA-1- differentiated mouse embryonic stem cells, respectively. These cell lines are not pluripotent and differentiate readily into endothelial cells in vitro and in vivo. Results We investigated the signaling pathway that maintains proliferation of these cells in an undifferentiated state, and demonstrate that PI3 K/Akt/mTOR, but not Raf/MEK/Erk, signaling in these cells was active during proliferation and was downregulated during endothelial differentiation. Inhibition of PI3 K/Akt/mTOR signaling, but not Raf/MEK/Erk, reduced proliferation and induced expression of endothelial specific proteins. During differentiation or inhibition of PI3 K/Akt/mTOR signaling, cyclinD2 transcript abundance in ribosome-enriched RNA but not in total RNA was reduced with a corresponding reduction in protein level. In contrast, transcript abundance of endothelial-specific genes e.g. Kdr, Tek and Pdgfrα in ribosome-enriched RNA fraction was not reduced and their protein levels were increased. Together these observations suggested that translational control mediated by PI3K/Akt/mTOR signaling was critical in regulating proliferation and endothelial differentiation of lineage-restricted RoSH-like stem cell lines. Conclusion This study highlights translation regulation as a critical regulatory mechanism during proliferation and differentiation in stem cells. PMID:17892597

Increased cardiogenesis in P19-GFP teratocarcinoma cells expressing the propeptide IGF-1Ea

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poudel, Bhawana; Bilbao, Daniel; Sarathchandra, Padmini

2011-12-16

Highlights: Black-Right-Pointing-Pointer In this study, we explored the function of IGF-1Ea propeptide in inducing cardiogenesis of stem cells. Black-Right-Pointing-Pointer IGF-1Ea promoted cardiac mesodermal induction in uncommitted cells. Black-Right-Pointing-Pointer Under differentiation condition, IGF-1Ea increased expression of cardiac differentiation markers. Black-Right-Pointing-Pointer Furthermore, it promoted formation of finely organized sarcomeric structure. Black-Right-Pointing-Pointer IGF-1Ea propeptide may be a good candidate to improve production of cardiomyocytes from pluripotent cells. -- Abstract: The mechanism implicated in differentiation of endogenous cardiac stem cells into cardiomyocytes to regenerate the heart tissue upon an insult remains elusive, limiting the therapeutical goals to exogenous cell injection and/or gene therapy. Wemore » have shown previously that cardiac specific overexpression of the insulin-like growth factor 1 propeptide IGF-1Ea induces beneficial myocardial repair after infarct. Although the mechanism is still under investigation, the possibility that this propeptide may be involved in promoting stem cell differentiation into the cardiac lineage has yet to be explored. To investigate whether IGF-1Ea promote cardiogenesis, we initially modified P19 embryonal carcinoma cells to express IGF-1Ea. Taking advantage of their cardiomyogenic nature, we analyzed whether overexpression of this propeptide affected cardiac differentiation program. The data herein presented showed for the first time that constitutively overexpressed IGF-1Ea increased cardiogenic differentiation program in both undifferentiated and DMSO-differentiated cells. In details, IGF-1Ea overexpression promoted localization of alpha-actinin in finely organized sarcomeric structure compared to control cells and upregulated the cardiac mesodermal marker NKX-2.5 and the ventricular structural protein MLC2v. Furthermore, activated IGF-1 signaling promoted cardiac mesodermal induction in undifferentiated cells independently of cell proliferation. This analysis suggests that IGF-1Ea may be a good candidate to improve both in vitro production of cardiomyocytes from pluripotent stem cells and in vivo activation of the differentiation program of cardiac progenitor cells.« less

RISC-mediated control of selected chromatin regulators stabilizes ground state pluripotency of mouse embryonic stem cells.

PubMed

Pandolfini, Luca; Luzi, Ettore; Bressan, Dario; Ucciferri, Nadia; Bertacchi, Michele; Brandi, Rossella; Rocchiccioli, Silvia; D'Onofrio, Mara; Cremisi, Federico

2016-05-06

Embryonic stem cells are intrinsically unstable and differentiate spontaneously if they are not shielded from external stimuli. Although the nature of such instability is still controversial, growing evidence suggests that protein translation control may play a crucial role. We performed an integrated analysis of RNA and proteins at the transition between naïve embryonic stem cells and cells primed to differentiate. During this transition, mRNAs coding for chromatin regulators are specifically released from translational inhibition mediated by RNA-induced silencing complex (RISC). This suggests that, prior to differentiation, the propensity of embryonic stem cells to change their epigenetic status is hampered by RNA interference. The expression of these chromatin regulators is reinstated following acute inactivation of RISC and it correlates with loss of stemness markers and activation of early cell differentiation markers in treated embryonic stem cells. We propose that RISC-mediated inhibition of specific sets of chromatin regulators is a primary mechanism for preserving embryonic stem cell pluripotency while inhibiting the onset of embryonic developmental programs.

Formation and hematopoietic differentiation of human embryoid bodies by suspension and hanging drop cultures.

PubMed

Cerdan, Chantal; Hong, Seok Ho; Bhatia, Mickie

2007-10-01

The in vitro aggregation of human embryonic stem cells (hESCs) into clusters termed embryoid bodies (EBs) allows for the spontaneous differentiation of cells representing endoderm, mesoderm, and ectoderm lineages. This stochastic process results however, in the generation of low numbers of differentiated cells, and can be enhanced to some extent by the addition of exogenous growth factors or overexpression of regulatory genes. In the authors' laboratory, the use of hematopoietic cytokines in combination with the mesoderm inducer bone morphogenetic protein-4 (BMP-4) was able to generate up to 90% of CD45(+) hematopoietic cells with colony-forming unit (CFU) activity. This unit describes two protocols that have been successfully applied in the authors' laboratory for the generation of EBs in (1) suspension and (2) hanging drop (HD) cultures from enzymatically digested clumps of undifferentiated hESC colonies.

APLP2 regulates neuronal stem cell differentiation during cortical development.

PubMed

Shariati, S Ali M; Lau, Pierre; Hassan, Bassem A; Müller, Ulrike; Dotti, Carlos G; De Strooper, Bart; Gärtner, Annette

2013-03-01

Expression of amyloid precursor protein (APP) and its two paralogues, APLP1 and APLP2 during brain development coincides with key cellular events such as neuronal differentiation and migration. However, genetic knockout and shRNA studies have led to contradictory conclusions about their role during embryonic brain development. To address this issue, we analysed in depth the role of APLP2 during neurogenesis by silencing APLP2 in vivo in an APP/APLP1 double knockout mouse background. We find that under these conditions cortical progenitors remain in their undifferentiated state much longer, displaying a higher number of mitotic cells. In addition, we show that neuron-specific APLP2 downregulation does not impact the speed or position of migrating excitatory cortical neurons. In summary, our data reveal that APLP2 is specifically required for proper cell cycle exit of neuronal progenitors, and thus has a distinct role in priming cortical progenitors for neuronal differentiation.

Integrating human stem cell expansion and neuronal differentiation in bioreactors

PubMed Central

Serra, Margarida; Brito, Catarina; Costa, Eunice M; Sousa, Marcos FQ; Alves, Paula M

2009-01-01

Background Human stem cells are cellular resources with outstanding potential for cell therapy. However, for the fulfillment of this application, major challenges remain to be met. Of paramount importance is the development of robust systems for in vitro stem cell expansion and differentiation. In this work, we successfully developed an efficient scalable bioprocess for the fast production of human neurons. Results The expansion of undifferentiated human embryonal carcinoma stem cells (NTera2/cl.D1 cell line) as 3D-aggregates was firstly optimized in spinner vessel. The media exchange operation mode with an inoculum concentration of 4 × 105 cell/mL was the most efficient strategy tested, with a 4.6-fold increase in cell concentration achieved in 5 days. These results were validated in a bioreactor where similar profile and metabolic performance were obtained. Furthermore, characterization of the expanded population by immunofluorescence microscopy and flow cytometry showed that NT2 cells maintained their stem cell characteristics along the bioreactor culture time. Finally, the neuronal differentiation step was integrated in the bioreactor process, by addition of retinoic acid when cells were in the middle of the exponential phase. Neurosphere composition was monitored and neuronal differentiation efficiency evaluated along the culture time. The results show that, for bioreactor cultures, we were able to increase significantly the neuronal differentiation efficiency by 10-fold while reducing drastically, by 30%, the time required for the differentiation process. Conclusion The culture systems developed herein are robust and represent one-step-forward towards the development of integrated bioprocesses, bridging stem cell expansion and differentiation in fully controlled bioreactors. PMID:19772662

[Embryonic stem cells and therapeutic cloning].

PubMed

Sunde, A; Eftedal, I

2001-08-30

Increased interest in the therapeutic use of human stem cells has emerged following significant progress in ongoing research. The cloning of a sheep, the isolation of human embryonic stem cells, and the discovery that adult stem cells may be reprogrammed taken together give substance to hopes that novel principles of treatment may be developed for a variety of serious conditions. Embryonic stem cells are derived from pre-embryos at the blastocyst stage and may give rise to all bodily tissues and cells. Animal models have demonstrated that embryonic stem cells when transplanted into adult hosts may differentiate and develop into cells and tissues applicable for treatment of a variety of conditions, including Parkinson's disease, multiple sclerosis, spinal injuries, cardiac stroke and cancer. Transplanted embryonic stem cells are exposed to immune reactions similar to those acting on organ transplants, hence immunosuppression of the recipient is generally required. It is, however, possible to obtain embryonic stem cells that are genetically identical to the patient's own cells by means of therapeutic cloning techniques. The nucleus from a somatic cell is transferred into an egg after removal of the egg's own genetic material. Under specific condition the egg will use genetic information from the somatic cell in organising the formation of a blastocyst which in turn generates embryonic stem cells. These cells have a genetic composition identical to that of the patient and are suitable for stem cell therapy.

Hmga2 is required for canonical WNT signaling during lung development

PubMed Central

2014-01-01

Background The high-mobility-group (HMG) proteins are the most abundant non-histone chromatin-associated proteins. HMG proteins are present at high levels in various undifferentiated tissues during embryonic development and their levels are strongly reduced in the corresponding adult tissues, where they have been implicated in maintaining and activating stem/progenitor cells. Here we deciphered the role of the high-mobility-group AT-hook protein 2 (HMGA2) during lung development by analyzing the lung of Hmga2-deficient mice (Hmga2 −/− ). Results We found that Hmga2 is expressed in the mouse embryonic lung at the distal airways. Analysis of Hmga2 −/− mice showed that Hmga2 is required for proper cell proliferation and distal epithelium differentiation during embryonic lung development. Hmga2 knockout led to enhanced canonical WNT signaling due to an increased expression of secreted WNT glycoproteins Wnt2b, Wnt7b and Wnt11 as well as a reduction of the WNT signaling antagonizing proteins GATA-binding protein 6 and frizzled homolog 2. Analysis of siRNA-mediated loss-of-function experiments in embryonic lung explant culture confirmed the role of Hmga2 as a key regulator of distal lung epithelium differentiation and supported the causal involvement of enhanced canonical WNT signaling in mediating the effect of Hmga2-loss-of-fuction. Finally, we found that HMGA2 directly regulates Gata6 and thereby modulates Fzd2 expression. Conclusions Our results support that Hmga2 regulates canonical WNT signaling at different points of the pathway. Increased expression of the secreted WNT glycoproteins might explain a paracrine effect by which Hmga2-knockout enhanced cell proliferation in the mesenchyme of the developing lung. In addition, HMGA2-mediated direct regulation of Gata6 is crucial for fine-tuning the activity of WNT signaling in the airway epithelium. Our results are the starting point for future studies investigating the relevance of Hmga2-mediated regulation of WNT signaling in the adult lung within the context of proper balance between differentiation and self-renewal of lung stem/progenitor cells during lung regeneration in both homeostatic turnover and repair after injury. PMID:24661562

Derivation of Multipotent Mesenchymal Precursors from Human Embryonic Stem Cells

PubMed Central

Barberi, Tiziano; Willis, Lucy M; Socci, Nicholas D; Studer, Lorenz

2005-01-01

Background Human embryonic stem cells provide access to the earliest stages of human development and may serve as a source of specialized cells for regenerative medicine. Thus, it becomes crucial to develop protocols for the directed differentiation of embryonic stem cells into tissue-restricted precursors. Methods and Findings Here, we present culture conditions for the derivation of unlimited numbers of pure mesenchymal precursors from human embryonic stem cells and demonstrate multilineage differentiation into fat, cartilage, bone, and skeletal muscle cells. Conclusion Our findings will help to elucidate the mechanism of mesoderm specification during embryonic stem cell differentiation and provide a platform to efficiently generate specialized human mesenchymal cell types for future clinical applications. PMID:15971941

Epigenetic Mechanisms Regulate MHC and Antigen Processing Molecules in Human Embryonic and Induced Pluripotent Stem Cells

PubMed Central

Suárez-Álvarez, Beatriz; Rodriguez, Ramón M.; Calvanese, Vincenzo; Blanco-Gelaz, Miguel A.; Suhr, Steve T.; Ortega, Francisco; Otero, Jesus; Cibelli, Jose B.; Moore, Harry; Fraga, Mario F.; López-Larrea, Carlos

2010-01-01

Background Human embryonic stem cells (hESCs) are an attractive resource for new therapeutic approaches that involve tissue regeneration. hESCs have exhibited low immunogenicity due to low levels of Mayor Histocompatibility Complex (MHC) class-I and absence of MHC class-II expression. Nevertheless, the mechanisms regulating MHC expression in hESCs had not been explored. Methodology/Principal Findings We analyzed the expression levels of classical and non-classical MHC class-I, MHC class-II molecules, antigen-processing machinery (APM) components and NKG2D ligands (NKG2D-L) in hESCs, induced pluripotent stem cells (iPSCs) and NTera2 (NT2) teratocarcinoma cell line. Epigenetic mechanisms involved in the regulation of these genes were investigated by bisulfite sequencing and chromatin immunoprecipitation (ChIP) assays. We showed that low levels of MHC class-I molecules were associated with absent or reduced expression of the transporter associated with antigen processing 1 (TAP-1) and tapasin (TPN) components in hESCs and iPSCs, which are involved in the transport and load of peptides. Furthermore, lack of β2-microglobulin (β2m) light chain in these cells limited the expression of MHC class I trimeric molecule on the cell surface. NKG2D ligands (MICA, MICB) were observed in all pluripotent stem cells lines. Epigenetic analysis showed that H3K9me3 repressed the TPN gene in undifferentiated cells whilst HLA-B and β2m acquired the H3K4me3 modification during the differentiation to embryoid bodies (EBs). Absence of HLA-DR and HLA-G expression was regulated by DNA methylation. Conclusions/Significance Our data provide fundamental evidence for the epigenetic control of MHC in hESCs and iPSCs. Reduced MHC class I and class II expression in hESCs and iPSCs can limit their recognition by the immune response against these cells. The knowledge of these mechanisms will further allow the development of strategies to induce tolerance and improve stem cell allograft acceptance. PMID:20419139

Embryonic stem cells: testing the germ-cell theory.

PubMed

Hochedlinger, Konrad

2011-10-25

The exact cellular origin of embryonic stem cells remains elusive. Now a new study provides compelling evidence that embryonic stem cells, established under conventional culture conditions, originate from a transient germ-cell state. Copyright © 2011 Elsevier Ltd. All rights reserved.

Biocompatibility of Synthetic Poly(ester urethane)/Polyhedral Oligomeric Silsesquioxane Matrices with Embryonic Stem Cell Proliferation and Differentiation

PubMed Central

Guo, Yan-Lin; Wang, Wenshou; Otaigbe, Joshua U.

2010-01-01

Incorporation of polyhedral oligomeric silsesquioxanes (POSS) into poly (ester urethane)s (PEU) as a building block results in a PEU/POSS hybrid polymer with increased mechanical strength and thermostability. An attractive feature of the new polymer is that it forms a porous matrix when cast in the form of a thin film, making it potentially useful in tissue engineering. In this study, we present detailed microscopic analysis of the PEU/POSS matrix and demonstrate its biocompatibility with cell culture. The PEU/POSS polymer forms a continuous porous matrix with open pores and interconnected grooves. From SEM image analysis, it is calculated that there are about 950 pores per mm2 of the matrix area with pore size ranging from 1 to 15 μm in diameter. The area occupied by the pores represents approximately 7.6 % of matrix area. Using mouse embryonic stem cells (ESCs), we demonstrate that the PEU/POSS matrix provides excellent support for cell proliferation and differentiation. Under the cell culture condition optimized to maintain self-renewal, ESCs grown on a PEU/POSS matrix exhibit undifferentiated morphology, express pluripotency markers, and have similar growth rate to cells grown on gelatin. When induced for differentiation, ESCs underwent dramatic morphological change, characterized by the loss of clonogenecity and increased cell size with well-expanded cytoskeleton networks. Differentiated cells are able to form a continuous monolayer that is closely embedded on the matrix. The excellent compatibility between the PEU/POSS matrix and ESC proliferation/differentiation demonstrates the potential of using PEU/POSS polymers in future ESC-based tissue engineering. PMID:20213627

Electrophysiological properties of prion-positive cardiac progenitors derived from murine embryonic stem cells.

PubMed

Fujii, Hiroshi; Ikeuchi, Yu; Kurata, Yasutaka; Ikeda, Nobuhito; Bahrudin, Udin; Li, Peili; Nakayama, Yuji; Endo, Ryo; Hasegawa, Akira; Morikawa, Kumi; Miake, Junichiro; Yoshida, Akio; Hidaka, Kyoko; Morisaki, Takayuki; Ninomiya, Haruaki; Shirayoshi, Yasuaki; Yamamoto, Kazuhiro; Hisatome, Ichiro

2012-01-01

The prion protein (PrP) has been reported to serve as a surface maker for isolation of cardiomyogenic progenitors from murine embryonic stem (ES) cells. Although PrP-positive cells exhibited automaticity, their electrophysiological characteristics remain unresolved. The aim of the present study was therefore to investigate the electrophysiological properties of PrP-positive cells in comparison with those of HCN4p-or Nkx2.5-positive cells. Differentiation of AB1, HCN5p-EGFP and hcgp7 ES cells into cardiac progenitors was induced by embryoid body (EB) formation. EBs were dissociated and cells expressing PrP, HCN4-EGFP and/or Nkx2.5-GFP were collected via flow cytometry. Sorted cells were subjected to reverse transcriptase-polymerase chain reaction, immunostaining and patch-clamp experiments. PrP-positive cells expressed mRNA of undifferentiation markers, first and second heart field markers, and cardiac-specific genes and ion channels, indicating their commitment to cardiomyogenic progenitors. PrP-positive cells with automaticity showed positive and negative chronotropic responses to isoproterenol and carbamylcholine, respectively. Hyperpolarization-activated cation current (I(f)) was barely detectable, whereas Na(+) and L-type Ca(2+) channel currents were frequently observed. Their spontaneous activity was slowed by inhibition of sarcoplasmic reticulum Ca(2+) uptake and release but not by blocking I(f). The maximum diastolic potential of their spontaneous firings was more depolarized than that of Nkx2.5-GFP-positive cells. PrP-positive cells contained cardiac progenitors that separated from the lineage of sinoatrial node cells. PrP can be used as a marker to enrich nascent cardiac progenitors.

The differentiation of hepatocyte-like cells from monkey embryonic stem cells.

PubMed

Ma, Xiaocui; Duan, Yuyou; Jung, Christine J; Wu, Jian; VandeVoort, Catherine A; Zern, Mark A

2008-12-01

Embryonic stem cells (ESC) hold great potential for the treatment of liver diseases. Here, we report the differentiation of rhesus macaque ESC along a hepatocyte lineage. The undifferentiated monkey ESC line, ORMES-6, was cultured in an optimal culture condition in an effort to differentiate them into hepatocyte-like cells in vitro. The functional efficacy of the differentiated hepatic cells was evaluated using RT-PCR for the expression of hepatocyte specific genes, and Western blot analysis and immunocytochemistry for hepatic proteins such as alpha-fetoprotein (AFP), albumin and alpha1-antitrypsin (alpha1-AT). Functional assays were performed using the periodic acid schiff (PAS) reaction and ELISA. The final yield of ESC-derived hepatocyte-like cells was measured by flow cytometry for cells that were transduced with a liver-specific lentivirus vector containing the alpha1-AT promoter driving the expression of green fluorescence protein (GFP). The treatment of monkey ESC with an optimal culture condition yielded hepatocyte-like cells that expressed albumin, alpha1-AT, AFP, hepatocyte nuclear factor 3beta, glucose-6-phophatase, and cytochrome P450 genes and proteins as determined by RT-PCR and Western blot analysis. Immunofluorescent staining showed the cells positive for albumin, AFP, and alpha1-AT. PAS staining demonstrated that the differentiated cells showed hepatocyte functional activity. Albumin could be detected in the medium after 20 days of differentiation. Flow cytometry data showed that 6.5 +/- 1.0% of the total differentiated cells were positive for GFP. These results suggest that by using a specific, empirically determined, culture condition, we were able to direct monkey ESC toward a hepatocyte lineage.

Sall4 is essential for stabilization, but not for pluripotency, of embryonic stem cells by repressing aberrant trophectoderm gene expression.

PubMed

Yuri, Shunsuke; Fujimura, Sayoko; Nimura, Keisuke; Takeda, Naoki; Toyooka, Yayoi; Fujimura, Yu-Ichi; Aburatani, Hiroyuki; Ura, Kiyoe; Koseki, Haruhiko; Niwa, Hitoshi; Nishinakamura, Ryuichi

2009-04-01

Sall4 is a mouse homolog of a causative gene of the autosomal dominant disorder Okihiro syndrome. We previously showed that the absence of Sall4 leads to lethality during peri-implantation and that Sall4-null embryonic stem (ES) cells proliferate poorly with intact pluripotency when cultured on feeder cells. Here, we report that, in the absence of feeder cells, Sall4-null ES cells express the trophectoderm marker Cdx2, but are maintained for a long period in an undifferentiated state with minimally affected Oct3/4 expression. Feeder-free Sall4-null ES cells contribute solely to the inner cell mass and epiblast in vivo, indicating that these cells still retain pluripotency and do not fully commit to the trophectoderm. These phenotypes could arise from derepression of the Cdx2 promoter, which is normally suppressed by Sall4 and the Mi2/NuRD HDAC complex. However, proliferation was impaired and G1 phase prolonged in the absence of Sall4, suggesting another role for Sall4 in cell cycle control. Although Sall1, also a Sall family gene, is known to genetically interact with Sall4 in vivo, Sall1-null ES cells have no apparent defects and no exacerbation is observed in ES cells lacking both Sall1 and Sall4, compared with Sall4-null cells. This suggests a unique role for Sall4 in ES cells. Thus, though Sall4 does not contribute to the central machinery of the pluripotency, it stabilizes ES cells by repressing aberrant trophectoderm gene expression.

Cripto-1 ablation disrupts alveolar development in the mouse mammary gland through a progesterone receptor-mediated pathway.

PubMed

Klauzinska, Malgorzata; McCurdy, David; Rangel, Maria Cristina; Vaidyanath, Arun; Castro, Nadia P; Shen, Michael M; Gonzales, Monica; Bertolette, Daniel; Bianco, Caterina; Callahan, Robert; Salomon, David S; Raafat, Ahmed

2015-11-01

Cripto-1, a member of the epidermal growth factor-Cripto-1/FRL-1/Cryptic family, is critical for early embryonic development. Together with its ligand Nodal, Cripto-1 has been found to be associated with the undifferentiated status of mouse and human embryonic stem cells. Several studies have clearly shown that Cripto-1 is involved in regulating branching morphogenesis and epithelial-mesenchymal transition of the mammary gland both in vitro and in vivo and together with the cofactor GRP78 is critical for the maintenance of mammary stem cells ex vivo. Our previous studies showed that mammary-specific overexpression of human Cripto-1 exhibited dramatic morphological alterations in nulliparous mice mammary glands. The present study shows a novel mechanism for Cripto-1 regulation of mammary gland development through direct effects on progesterone receptor expression and pathways regulated by progesterone in the mammary gland. We demonstrate a strict temporal regulation of mouse Cripto-1 (mCripto-1) expression that occurs during mammary gland development and a stage-specific function of mCripto-1 signaling during mammary gland development. Our data suggest that Cripto-1, like the progesterone receptor, is not required for the initial ductal growth but is essential for subsequent side branching and alveologenesis during the initial stages of pregnancy. Dissection of the mechanism by which this occurs indicates that mCripto-1 activates receptor activator NF-κB/receptor activator NF-κB ligand, and NF-κB signaling pathways. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

In situ label-free quantification of human pluripotent stem cells with electrochemical potential.

PubMed

Yea, Cheol-Heon; Jeong, Ho-Chang; Moon, Sung-Hwan; Lee, Mi-Ok; Kim, Kyeong-Jun; Choi, Jeong-Woo; Cha, Hyuk-Jin

2016-01-01

Conventional methods for quantification of undifferentiated pluripotent stem cells such as fluorescence-activated cell sorting and real-time PCR analysis have technical limitations in terms of their sensitivity and recyclability. Herein, we designed a real-time in situ label-free monitoring system on the basis of a specific electrochemical signature of human pluripotent stem cells in vitro. The intensity of the signal of hPSCs highly corresponded to the cell number and remained consistent in a mixed population with differentiated cells. The electrical charge used for monitoring did not markedly affect the proliferation rate or molecular characteristics of differentiated human aortic smooth muscle cells. After YM155 treatment to ablate undifferentiated hPSCs, their specific signal was significantly reduced. This suggests that detection of the specific electrochemical signature of hPSCs would be a valid approach to monitor potential contamination of undifferentiated hPSCs, which can assess the risk of teratoma formation efficiently and economically. Copyright © 2015 Elsevier Ltd. All rights reserved.

Relationship between ketamine-induced developmental neurotoxicity and NMDA receptor-mediated calcium influx in neural stem cell-derived neurons.

PubMed

Wang, Cheng; Liu, Fang; Patterson, Tucker A; Paule, Merle G; Slikker, William

2017-05-01

Ketamine, a noncompetitive NMDA receptor antagonist, is used as a general anesthetic and recent data suggest that general anesthetics can cause neuronal damage when exposure occurs during early brain development. To elucidate the underlying mechanisms associated with ketamine-induced neurotoxicity, stem cell-derived models, such as rodent neural stem cells harvested from rat fetuses and/or neural stem cells derived from human induced pluripotent stem cells (iPSC) can be utilized. Prolonged exposure of rodent neural stem cells to clinically-relevant concentrations of ketamine resulted in elevated NMDA receptor levels as indicated by NR1subunit over-expression in neurons. This was associated with enhanced damage in neurons. In contrast, the viability and proliferation rate of undifferentiated neural stem cells were not significantly affected after ketamine exposure. Calcium imaging data indicated that 50μM NMDA did not cause a significant influx of calcium in typical undifferentiated neural stem cells; however, it did produce an immediate elevation of intracellular free Ca 2+ [Ca 2+ ] i in differentiated neurons derived from the same neural stem cells. This paper reviews the literature on this subject and previous findings suggest that prolonged exposure of developing neurons to ketamine produces an increase in NMDA receptor expression (compensatory up-regulation) which allows for a higher/toxic influx of calcium into neurons once ketamine is removed from the system, leading to neuronal cell death likely due to elevated reactive oxygen species generation. The absence of functional NMDA receptors in cultured neural stem cells likely explains why clinically-relevant concentrations of ketamine did not affect undifferentiated neural stem cell viability. Published by Elsevier B.V.

Undifferentiated (embryonal) liver sarcoma: synchronous and metachronous occurrence with neoplasms other than mesenchymal liver hamartoma.

PubMed

Gasljevic, Gorana; Lamovec, Janez; Jancar, Janez

2011-08-01

Undifferentiated (embryonal) liver sarcoma (UELS) is a rare tumor that typically occurs in children. The association of UELS with neoplasm other than mesenchymal liver hamartoma is exceedingly rare. The aim of the study was to report 3 cases of UELS, 2 of them being interesting because of their association with another neoplasm, vaginal embryonal rhabdomyosarcoma in a teenage girl and B-acute lymphoblastic leukemia in a middle-aged woman. Besides, one of our cases of UELS, in a 58-year-old woman, is an extremely rare presentation of such a tumor in a middle-aged adult. The patient's clinical features, therapy, and pathologic results were reviewed; immunohistochemical analysis and, in 2 cases, electron microscopy were performed. In this study, all 3 patients were females aged 13, 13, and 58 years. Histopathologic evaluation of resected liver tumors confirmed the diagnosis of UELS in all of them. In 2 of the cases, metachronous occurrence of UELS with vaginal embryonal rhabdomyosarcoma in a teenage girl and B-acute lymphoblastic leukemia in a middle-aged woman is described. Careful clinical analysis, histologic studies, and immunohistochemistry are mandatory to distinguish UELS from other hepatic malignancies with similar or overlapping features and to exclude the possibility of other tumors that may be considered in the differential diagnosis. The association of UELS with another neoplasm is exceedingly rare. Copyright © 2011 Elsevier Inc. All rights reserved.

Normal development of the female reproductive system

EPA Science Inventory

The embryonic development of the female reproductive system involves a progression of events that is conserved across vertebrate species. The early gonad progresses from a form that is undifferentiated in both genotypic males and females. Rudimentary male (Wolffian) and female (M...

Different effects of enhanced and reduced expression of pub gene on the formation of embryoid bodies by cultured embryonic mouse stem cell.

PubMed

Novosadova, E V; Manuilova, E S; Arsen'eva, E L; Khaidarova, N V; Dolotov, O V; Inozemtseva, L S; Kozachenkov, K Yu; Tarantul, V Z; Grivennikov, I A

2005-07-01

The effects of pub gene on proliferation and initial stages of differentiation of embryonic mouse stem cells were studied in vitro. To this end we used enhanced expression of human pub gene (hpub) and suppression of expression of mouse endogenous pub gene with RNA-interference in embryonic stem cells. Proliferative activity of genetically modified polyclonal lines of the embryonic stem cells transfected with plasmids carrying expressing hpub gene or plasmids generating small interference RNA to this gene did not differ from that of the control cells. Inhibition of expression of endogenous pub gene in embryonic stem cells using small interference RNA 2-fold decreased the formation of embryoid bodies, at the same time additional expression of exogenous hpub gene almost 2-fold increased their number in comparison with the control. It was hypothesized that pub gene participates in early stages of differentiation of embryonic stem cells leading to the formation of embryoid bodies.

Isolation and characterization of the trophectoderm from the Arabian camel (Camelus dromedarius).

PubMed

Saadeldin, Islam M; Swelum, Ayman Abdel-Aziz; Elsafadi, Mona; Moumen, Abdullah F; Alzahrani, Faisal A; Mahmood, Amer; Alfayez, Musaad; Alowaimer, Abdullah N

2017-09-01

We isolated and characterized trophoblast from in vivo-derived camel embryos and compared with embryonic stem-like cells. Camel embryos were flushed on day 8 post-insemination and used to derive trophectoderm and embryonic stem-like cells under feeder-free culture conditions using a basement membrane matrix. Embryos were evaluated for the expression of POU5F1, MYC, KLF4, SOX2, CDX2, and KRT8 mRNA transcripts by relative quantitative polymerase chain reaction. Camel embryos grew and expanded to ∼4.5 mm and maintained their vesicular shape in vitro for 21 days post-insemination. Trophoblast and embryonic stem-like cell lines grew under feeder-free culture conditions and showed distinct morphological criteria and normal chromosomal counts. Embryonic stem-like cells showed positive staining in the alkaline phosphatase reaction. Trophoblast cells showed a significant increase in CDX2, KRT8, KLF4, and SOX2 expression compared with embryonic stem-like cells and whole embryos. Embryonic stem-like cells showed a significant decrease in CDX2 expression and increase in SOX2 and KRT8 expression compared to embryonic expression. POU5F1 and MYC expression showed no difference between embryos and both cell lines. We characterized embryo survival in vitro, particularly the derivation of trophectoderm and embryonic stem-like cells, providing a foundation for further analysis of early embryonic development and placentation in camels. Copyright © 2017 Elsevier Ltd. All rights reserved.

Establishment of mouse embryonic stem cells from isolated blastomeres and whole embryos using three derivation methods

PubMed Central

González, Sheyla; Ibáñez, Elena

2010-01-01

Purpose The aim of the present study is to compare three previously described mouse embryonic stem cell derivation methods to evaluate the influence of culture conditions, number of isolated blastomeres and embryonic stage in the derivation process. Methods Three embryonic stem cell derivation methods: standard, pre-adhesion and defined culture medium method, were compared in the derivation from isolated blastomeres and whole embryos at 4- and 8-cell stages. Results A total of 200 embryonic stem cell lines were obtained with an efficiency ranging from 1.9% to 72%. Conclusions Using either isolated blastomeres or whole embryos, the highest rates of mouse embryonic stem cell establishment were achieved with the defined culture medium method and efficiencies increased as development progressed. Using isolated blastomeres, efficiencies increased in parallel to the proportion of the embryo volume used to start the derivation process. PMID:20862536

DSG2 Is a Functional Cell Surface Marker for Identification and Isolation of Human Pluripotent Stem Cells.

PubMed

Park, Jongjin; Son, Yeonsung; Lee, Na Geum; Lee, Kyungmin; Lee, Dong Gwang; Song, Jinhoi; Lee, Jaemin; Kim, Seokho; Cho, Min Ji; Jang, Ju-Hong; Lee, Jangwook; Park, Jong-Gil; Kim, Yeon-Gu; Kim, Jang-Seong; Lee, Jungwoon; Cho, Yee Sook; Park, Young-Jun; Han, Baek Soo; Bae, Kwang-Hee; Han, Seungmin; Kang, Byunghoon; Haam, Seungjoo; Lee, Sang-Hyun; Lee, Sang Chul; Min, Jeong-Ki

2018-06-08

Pluripotent stem cells (PSCs) represent the most promising clinical source for regenerative medicine. However, given the cellular heterogeneity within cultivation and safety concerns, the development of specific and efficient tools to isolate a pure population and eliminate all residual undifferentiated PSCs from differentiated derivatives is a prerequisite for clinical applications. In this study, we raised a monoclonal antibody and identified its target antigen as desmoglein-2 (DSG2). DSG2 co-localized with human PSC (hPSC)-specific cell surface markers, and its expression was rapidly downregulated upon differentiation. The depletion of DSG2 markedly decreased hPSC proliferation and pluripotency marker expression. In addition, DSG2-negative population in hPSCs exhibited a notable suppression in embryonic body and teratoma formation. The actions of DSG2 in regulating the self-renewal and pluripotency of hPSCs were predominantly exerted through the regulation of β-catenin/Slug-mediated epithelial-to-mesenchymal transition. Our results demonstrate that DSG2 is a valuable PSC surface marker that is essential for the maintenance of PSC self-renewal. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Parthenogenesis-derived Multipotent Stem Cells Adapted for Tissue Engineering Applications

PubMed Central

Koh, Chester J.; Delo, Dawn M.; Lee, Jang Won; Siddiqui, M. Minhaj; Lanza, Robert P.; Soker, Shay; Yoo, James J.; Atala, Anthony

2009-01-01

Embryonic stem cells are envisioned as a viable source of pluripotent cells for use in regenerative medicine applications when donor tissue is not available. However, most current harvest techniques for embryonic stem cells require the destruction of embryos, which has led to significant political and ethical limitations on their usage. Parthenogenesis, the process by which an egg can develop into an embryo in the absence of sperm, may be a potential source of embryonic stem cells that may avoid some of the political and ethical concerns surrounding embryonic stem cells. Here we provide the technical aspects of embryonic stem cell isolation and expansion from the parthenogenetic activation of oocytes. These cells were characterized for their stem-cell properties. In addition, these cells were induced to differentiate to the myogenic, osteogenic, adipogenic, and endothelial lineages, and were able to form muscle-like and bony-like tissue in vivo. Furthermore, parthenogenetic stem cells were able to integrate into injured muscle tissue. Together, these results demonstrate that parthenogenetic stem cells can be successfully isolated and utilized for various tissue engineering applications. PMID:18799133

Establishment of mouse expanded potential stem cells

PubMed Central

Gao, Xuefei; Antunes, Liliana; Yu, Yong; Zhu, Zhexin; Wang, Juexuan; Kolodziejczyk, Aleksandra A.; Campos, Lia S.; Wang, Cui; Yang, Fengtang; Zhong, Zhen; Fu, Beiyuan; Eckersley-Maslin, Melanie A.; Woods, Michael; Tanaka, Yosuke; Chen, Xi; Wilkinson, Adam C.; Bussell, James; White, Jacqui; Ramirez-Solis, Ramiro; Reik, Wolf; Göttgens, Berthold; Teichmann, Sarah A.; Tam, Patrick P. L.; Nakauchi, Hiromitsu; Zou, Xiangang; Lu, Liming; Liu, Pentao

2018-01-01

Mouse embryonic stem cells derived from the epiblast1 contribute to the somatic lineages and the germline but are excluded from the extra-embryonic tissues that are derived from the trophectoderm and the primitive endoderm2 upon reintroduction to the blastocyst. Here we report that cultures of expanded potential stem cells can be established from individual eight-cell blastomeres, and by direct conversion of mouse embryonic stem cells and induced pluripotent stem cells. Remarkably, a single expanded potential stem cell can contribute both to the embryo proper and to the trophectoderm lineages in a chimaera assay. Bona fide trophoblast stem cell lines and extra-embryonic endoderm stem cells can be directly derived from expanded potential stem cells in vitro. Molecular analyses of the epigenome and single-cell transcriptome reveal enrichment for blastomere-specific signature and a dynamic DNA methylome in expanded potential stem cells. The generation of mouse expanded potential stem cells highlights the feasibility of establishing expanded potential stem cells for other mammalian species. PMID:29019987

Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay

EPA Science Inventory

The Embryonic Stem Cell Test (EST) is an assay which evaluates xenobiotic-induced effects using three endpoints: mouse embryonic stem cell (mESC) differentiation, mESC viability, and 3T3-cell viability. Our research goal was to develop an improved high-throughput assay by establi...

Blastema cells derived from New Zealand white rabbit's pinna carry stemness properties as shown by differentiation into insulin producing, neural, and osteogenic lineages representing three embryonic germ layers.

PubMed

Saeinasab, Morvarid; Matin, Maryam M; Rassouli, Fatemeh B; Bahrami, Ahmad Reza

2016-05-01

Stem cells (SCs) are known as undifferentiated cells with self-renewal and differentiation capacities. Regeneration is a phenomenon that occurs in a limited number of animals after injury, during which blastema tissue is formed. It has been hypothesized that upon injury, the dedifferentiation of surrounding tissues leads into the appearance of cells with SC characteristics. In present study, stem-like cells (SLCs) were obtained from regenerating tissue of New Zealand white rabbit's pinna and their stemness properties were examined by their capacity to differentiate toward insulin producing cells (IPCs), as well as neural and osteogenic lineages. Differentiation was induced by culture of SLCs in defined medium, and cell fates were monitored by specific staining, RT-PCR and flow cytometry assays. Our results revealed that dithizone positive cells, which represent IPCs, and islet-like structures appeared 1 week after induction of SLCs, and this observation was confirmed by the elevated expression of Ins, Pax6 and Glut4 at mRNA level. Furthermore, SLCs were able to express neural markers as early as 1 week after retinoic acid treatment. Finally, SLCs were able to differentiate into osteogenic lineage, as confirmed by Alizarin Red S staining and RT-PCR studies. In conclusion, SLCs, which could successfully differentiate into cells derived from all three germ layers, can be considered as a valuable model to study developmental biology and regenerative medicine.

[Cell therapy for Parkinson's disease: III. Neonatal, fetal and embryonic stem cell-based applications].

PubMed

Anisimov, S V

2009-01-01

Motor dysfunctions in Parkinson's disease are believed to be primarily due to the degeneration of dopaminergic neurons located in the substantia nigra pars compacta. Numerous cell replacement therapy approaches have been developed and tested, including these based on donor cell transplantation (embryonic and adult tissue-derived), adult mesenchymal stem cells (hMSCs)-, neural stem cells (hNSCs)- and finally human embryonic stem cells (hESCs)-based. Despite the progress achieved, numerous difficulties prevent wider practical application of stem cell-based therapy approaches for the treatment of Parkinson's disease. Among the latter, ethical, safety and technical issues stand out. Current series of reviews (Cell therapy for Parkinson's disease: I. Embryonic and adult donor tissue-based applications; II. Adult stem cell-based applications; III. Neonatal, fetal and embryonic stem cell-based applications; IV. Risks and future trends) aims providing a balanced and updated view on various issues associated with cell types (including stem cells) in regards to their potential in the treatment of Parkinson's disease. Essential features of the individual cell subtypes, principles of available cell handling protocols, transplantation, and safety issues are discussed extensively.

Cryopreservation of pluripotent stem cell aggregates in defined protein-free formulation.

PubMed

Sart, Sébastien; Ma, Teng; Li, Yan

2013-01-01

Cultivation of undifferentiated pluripotent stem cells (PSCs) as aggregates has emerged as an efficient culture configuration, enabling rapid and controlled large scale expansion. Aggregate-based PSC cryopreservation facilitates the integrated process of cell expansion and cryopreservation, but its feasibility has not been demonstrated. The goals of current study are to assess the suitability of cryopreserving intact mouse embryonic stem cell (mESC) aggregates and investigate the effects of aggregate size and the formulation of cryopreservation solution on mESC survival and recovery. The results demonstrated the size-dependent cell survival and recovery of intact aggregates. In particular, the generation of reactive oxygen species (ROS) and caspase activation were reduced for small aggregates (109 ± 55 μm) compared to medium (245 ± 77 μm) and large (365 ± 141 μm) ones, leading to the improved cell recovery. In addition, a defined protein-free formulation was tested and found to promote the aggregate survival, eliminating the cell exposure to animal serum. The cryopreserved aggregates also maintained the pluripotent markers and the differentiation capacity into three-germ layers after thawing. In summary, the cryopreservation of small PSC aggregates in a defined protein-free formulation was shown to be a suitable approach toward a fully integrated expansion and cryopreservation process at large scale. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

Morphological Analysis of Human Induced Pluripotent Stem Cells During Induced Differentiation and Reverse Programming

PubMed Central

Magniez, Aurélie; Oudrhiri, Noufissa; Féraud, Olivier; Bacci, Josette; Gobbo, Emilie; Proust, Stéphanie; Turhan, Ali G.

2014-01-01

Abstract The fine analysis of cell components during the generation of pluripotent cells and their comparison to bone fide human embryonic stem cells (hESCs) are valuable tools to understand their biological behavior. In this report, human mesenchymal cells (hMSCs) generated from the human ES cell line H9, were reprogrammed back to induced pluripotent state using Oct-4, Sox2, Nanog, and Lin28 transgenes. Human induced pluripotent stem cells (hIPSCs) were analyzed using electron microscopy and compared with regard to the original hESCs and the hMSCs from which they were derived. This analysis shows that hIPSCs and the original hESCs are morphologically undistinguishable but differ from the hMSCs with respect to the presence of several morphological features of undifferentiated cells at both the cytoplasmic (ribosomes, lipid droplets, glycogen, scarce reticulum) and nuclear levels (features of nuclear plasticity, presence of euchromatin, reticulated nucleoli). We show that hIPSC colonies generated this way presented epithelial aspects with specialized junctions highlighting morphological criteria of the mesenchymal–epithelial transition in cells engaged in a successful reprogramming process. Electron microscopic analysis revealed also specific morphological aspects of partially reprogrammed cells. These results highlight the valuable use of electron microscopy for a better knowledge of the morphological aspects of IPSC and cellular reprogramming. PMID:25371857

'Shovel-Ready' applications of stem cell advances for pediatric heart disease.

PubMed

Files, Matthew D; Boucek, Robert J

2012-10-01

The past decade has seen remarkable advances in the field of stem cell biology. Many new technologies and applications are passing the translational phase and likely will soon be relevant for the clinical pediatric cardiologist. This review will focus on two advances in basic science that are now translating into clinical trials. The first advance is the recognition, characterization, and recent therapeutic application of resident cardiac progenitor cells (CPCs). Early results of adult trials and scattered case reports in pediatric patients support expanding CPC-based trials for end-stage heart failure in pediatric patients. The relative abundance of CPCs in the neonate and young child offers greater potential benefits in heart failure treatment than has been realized to date. The second advance is the technology of induced pluripotent stem cells (iPSCs), which reprograms differentiated somatic cells to an undifferentiated embryonic-like state. When iPSCs are differentiated into cardiomyocytes, they model a patient's specific disease, test pharmaceuticals, and potentially provide an autologous source for cell-based therapy. The therapeutic recruitment and/or replacement of CPCs has potential for enhancing cardiac repair and regeneration in children with heart failure. Use of iPSCs to model heart disease holds great potential to gain new insights into diagnosis, pathophysiology, and disease-specific management for genetic-based cardiovascular diseases that are prevalent in pediatric patients.

Osteopontin is a Novel Marker of Pancreatic Ductal Tissues and of Undifferentiated Pancreatic Precursors in Mice

PubMed Central

Kilic, Gamze; Wang, Junfeng; Sosa-Pineda, Beatriz

2008-01-01

Matricellular proteins mediate both tissue morphogenesis and tissue homeostasis in important ways because they modulate cell-matrix and cell-cell interactions. In this study, we found that the matricellular protein osteopontin (Opn) is a novel marker of undifferentiated pancreatic precursors and pancreatic ductal tissues in mice. Our analysis also underscored a specific, dynamic profile of Opn expression in embryonic pancreatic tissues that suggests the participation of this protein’s function in processes involving cell migration, cell-cell interactions, or both. Surprisingly, our analysis of Opn-deficient pancreata did not reveal obvious alterations in the morphology or differentiation of these tissues. Therefore, in embryonic pancreatic tissues, it is possible that other proteins act redundantly to Opn or that this protein’s function is dispensable for pancreas development. Finally, the maintenance of Opn expression in pancreatic tissues of adults argues for a possible function of this protein in injury and pathologic responses. PMID:16518820

The reprogramming factor nuclear receptor subfamily 5, group A, member 2 cannot replace octamer-binding transcription factor 4 function in the self-renewal of embryonic stem cells.

PubMed

Choi, Kyeng-Won; Oh, Hye-Rim; Lee, Jaeyoung; Lim, Bobae; Han, Yong-Mahn; Oh, Junseo; Kim, Jungho

2014-02-01

Although octamer-binding transcription factor 4 (Oct-4) is one of the most intensively studied factors in mammalian development, no cellular genes capable of replacing Oct-4 function in embryonic stem (ES) cells have been found. Recent data show that nuclear receptor subfamily 5, group A, member 2 (Nr5a2) is able to replace Oct-4 function in the reprogramming process; however, it is unclear whether Nr5a2 can replace Oct-4 function in ES cells. In this study, the ability of Nr5a2 to maintain self-renewal and pluripotency in ES cells was investigated. Nr5a2 localized to the nucleus in ES cells, similarly to Oct-4. However, expression of Nr5a2 failed to rescue the stem cell phenotype or to maintain the self-renewal ability of ES cells. Furthermore, as compared with Oct-4-expressing ES cells, Nr5a2-expressing ES cells showed a reduced number of cells in S-phase, did not expand normally, and did not remain in an undifferentiated state. Ectopic expression of Nr5a2 in ES cells was not able to activate transcription of ES cell-specific genes, and gene expression profiling demonstrated differences between Nr5a2-expressing and Oct-4-expressing ES cells. In addition, Nr5a2-expressing ES cells were not able to form teratomas in nude mice. Taken together, these results strongly suggest that the gene regulation properties of Nr5a2 and Oct-4 and their abilities to confer self-renewal and pluripotency of ES cells differ. The present study provides strong evidence that Nr5a2 cannot replace Oct-4 function in ES cells. © 2013 FEBS.

Impact of stirred suspension bioreactor culture on the differentiation of murine embryonic stem cells into cardiomyocytes.

PubMed

Shafa, Mehdi; Krawetz, Roman; Zhang, Yuan; Rattner, Jerome B; Godollei, Anna; Duff, Henry J; Rancourt, Derrick E

2011-12-14

Embryonic stem cells (ESCs) can proliferate endlessly and are able to differentiate into all cell lineages that make up the adult organism. Under particular in vitro culture conditions, ESCs can be expanded and induced to differentiate into cardiomyocytes in stirred suspension bioreactors (SSBs). However, in using these systems we must be cognizant of the mechanical forces acting upon the cells. The effect of mechanical forces and shear stress on ESC pluripotency and differentiation has yet to be clarified. The purpose of this study was to investigate the impact of the suspension culture environment on ESC pluripotency during cardiomyocyte differentiation. Murine D3-MHC-neo(r) ESCs formed embyroid bodies (EBs) and differentiated into cardiomyocytes over 25 days in static culture and suspension bioreactors. G418 (Geneticin) was used in both systems from day 10 to enrich for cardiomyocytes by eliminating non-resistant, undifferentiated cells. Treatment of EBs with 1 mM ascorbic acid and 0.5% dimethyl sulfoxide from day 3 markedly increased the number of beating EBs, which displayed spontaneous and cadenced contractile beating on day 11 in the bioreactor. Our results showed that the bioreactor differentiated cells displayed the characteristics of fully functional cardiomyocytes. Remarkably, however, our results demonstrated that the bioreactor differentiated ESCs retained their ability to express pluripotency markers, to form ESC-like colonies, and to generate teratomas upon transplantation, whereas the cells differentiated in adherent culture lost these characteristics. This study demonstrates that although cardiomyocyte differentiation can be achieved in stirred suspension bioreactors, the addition of medium enhancers is not adequate to force complete differentiation as fluid shear forces appear to maintain a subpopulation of cells in a transient pluripotent state. The development of successful ESC differentiation protocols within suspension bioreactors demands a more complete understanding of the impacts of shear forces on the regulation of pluripotency and differentiation in pluripotent stem cells.

Impact of stirred suspension bioreactor culture on the differentiation of murine embryonic stem cells into cardiomyocytes

PubMed Central

2011-01-01

Background Embryonic stem cells (ESCs) can proliferate endlessly and are able to differentiate into all cell lineages that make up the adult organism. Under particular in vitro culture conditions, ESCs can be expanded and induced to differentiate into cardiomyocytes in stirred suspension bioreactors (SSBs). However, in using these systems we must be cognizant of the mechanical forces acting upon the cells. The effect of mechanical forces and shear stress on ESC pluripotency and differentiation has yet to be clarified. The purpose of this study was to investigate the impact of the suspension culture environment on ESC pluripotency during cardiomyocyte differentiation. Results Murine D3-MHC-neor ESCs formed embyroid bodies (EBs) and differentiated into cardiomyocytes over 25 days in static culture and suspension bioreactors. G418 (Geneticin) was used in both systems from day 10 to enrich for cardiomyocytes by eliminating non-resistant, undifferentiated cells. Treatment of EBs with 1 mM ascorbic acid and 0.5% dimethyl sulfoxide from day 3 markedly increased the number of beating EBs, which displayed spontaneous and cadenced contractile beating on day 11 in the bioreactor. Our results showed that the bioreactor differentiated cells displayed the characteristics of fully functional cardiomyocytes. Remarkably, however, our results demonstrated that the bioreactor differentiated ESCs retained their ability to express pluripotency markers, to form ESC-like colonies, and to generate teratomas upon transplantation, whereas the cells differentiated in adherent culture lost these characteristics. Conclusions This study demonstrates that although cardiomyocyte differentiation can be achieved in stirred suspension bioreactors, the addition of medium enhancers is not adequate to force complete differentiation as fluid shear forces appear to maintain a subpopulation of cells in a transient pluripotent state. The development of successful ESC differentiation protocols within suspension bioreactors demands a more complete understanding of the impacts of shear forces on the regulation of pluripotency and differentiation in pluripotent stem cells. PMID:22168552

HLA Class I Depleted hESC as a Source of Hypoimmunogenic Cells for Tissue Engineering Applications.

PubMed

Karabekian, Zaruhi; Ding, Hao; Stybayeva, Gulnaz; Ivanova, Irina; Muselimyan, Narine; Haque, Amranul; Toma, Ian; Posnack, Nikki G; Revzin, Alexander; Leitenberg, David; Laflamme, Michael A; Sarvazyan, Narine

2015-10-01

Rapidly improving protocols for the derivation of autologous cells from stem cell sources is a welcome development. However, there are many circumstances when off-the-shelf universally immunocompatible cells may be needed. Embryonic stem cells (ESCs) provide a unique opportunity to modify the original source of differentiated cells to minimize their rejection by nonautologous hosts. Immune rejection of nonautologous human embryonic stem cell (hESC) derivatives can be reduced by downregulating human leukocyte antigen (HLA) class I molecules, without affecting the ability of these cells to differentiate into specific lineages. Beta-2-microglobulin (B2M) expression was decreased by lentiviral transduction using human anti-HLA class I light-chain B2M short hairpin RNA. mRNA levels of B2M were decreased by 90% in a RUES2-modified hESC line, as determined by quantitative real time-polymerase chain reaction analysis. The transduced cells were selected under puromycin pressure and maintained in an undifferentiated state. The latter was confirmed by Oct4 and Nanog expression, and by the formation of characteristic round-shaped colonies. B2M downregulation led to diminished HLA-I expression on the cell surface, as determined by flow cytometry. When used as target cells in a mixed lymphocyte reaction assay, transduced hESCs and their differentiated derivatives did not stimulate allogeneic T-cell proliferation. Using a cardiac differentiation protocol, transduced hESCs formed a confluent layer of cardiac myocytes and maintained a low level of B2M expression. Transduced hESCs were also successfully differentiated into a hepatic lineage, validating their capacity to differentiate into multiple lineages. HLA-I depletion does not preclude hESC differentiation into cardiac or hepatic lineages. This methodology can be used to engineer tissue from nonautologous hESC sources with improved immunocompatibility.

HLA Class I Depleted hESC as a Source of Hypoimmunogenic Cells for Tissue Engineering Applications

PubMed Central

Karabekian, Zaruhi; Ding, Hao; Stybayeva, Gulnaz; Ivanova, Irina; Muselimyan, Narine; Haque, Amranul; Toma, Ian; Posnack, Nikki G.; Revzin, Alexander; Leitenberg, David; Laflamme, Michael A.

2015-01-01

Background: Rapidly improving protocols for the derivation of autologous cells from stem cell sources is a welcome development. However, there are many circumstances when off-the-shelf universally immunocompatible cells may be needed. Embryonic stem cells (ESCs) provide a unique opportunity to modify the original source of differentiated cells to minimize their rejection by nonautologous hosts. Hypothesis: Immune rejection of nonautologous human embryonic stem cell (hESC) derivatives can be reduced by downregulating human leukocyte antigen (HLA) class I molecules, without affecting the ability of these cells to differentiate into specific lineages. Methods and Results: Beta-2-microglobulin (B2M) expression was decreased by lentiviral transduction using human anti-HLA class I light-chain B2M short hairpin RNA. mRNA levels of B2M were decreased by 90% in a RUES2-modified hESC line, as determined by quantitative real time-polymerase chain reaction analysis. The transduced cells were selected under puromycin pressure and maintained in an undifferentiated state. The latter was confirmed by Oct4 and Nanog expression, and by the formation of characteristic round-shaped colonies. B2M downregulation led to diminished HLA-I expression on the cell surface, as determined by flow cytometry. When used as target cells in a mixed lymphocyte reaction assay, transduced hESCs and their differentiated derivatives did not stimulate allogeneic T-cell proliferation. Using a cardiac differentiation protocol, transduced hESCs formed a confluent layer of cardiac myocytes and maintained a low level of B2M expression. Transduced hESCs were also successfully differentiated into a hepatic lineage, validating their capacity to differentiate into multiple lineages. Conclusions: HLA-I depletion does not preclude hESC differentiation into cardiac or hepatic lineages. This methodology can be used to engineer tissue from nonautologous hESC sources with improved immunocompatibility. PMID:26218149

Regulatory mechanism of protein metabolic pathway during the differentiation process of chicken male germ cell.

PubMed

Li, Dong; Zuo, Qisheng; Lian, Chao; Zhang, Lei; Shi, Qingqing; Zhang, Zhentao; Wang, Yingjie; Ahmed, Mahmoud F; Tang, Beibei; Xiao, Tianrong; Zhang, Yani; Li, Bichun

2015-08-01

We explored the regulatory mechanism of protein metabolism during the differentiation process of chicken male germ cells and provide a basis for improving the induction system of embryonic stem cell differentiation to male germ cells in vitro. We sequenced the transcriptome of embryonic stem cells, primordial germ cells, and spermatogonial stem cells with RNA sequencing (RNA-Seq), bioinformatics analysis methods, and detection of the key genes by quantitative reverse transcription PCR (qRT-PCR). Finally, we found 16 amino acid metabolic pathways enriched in the biological metabolism during the differentiation process of embryonic stem cells to primordial germ cells and 15 amino acid metabolic pathways enriched in the differentiation stage of primordial germ cells to spermatogonial stem cells. We found three pathways, arginine-proline metabolic pathway, tyrosine metabolic pathway, and tryptophan metabolic pathway, significantly enriched in the whole differentiation process of embryonic stem cells to spermatogonial stem cells. Moreover, for these three pathways, we screened key genes such as NOS2, ADC, FAH, and IDO. qRT-PCR results showed that the expression trend of these genes were the same to RNA-Seq. Our findings showed that the three pathways and these key genes play an important role in the differentiation process of embryonic stem cells to male germ cells. These results provide basic information for improving the induction system of embryonic stem cell differentiation to male germ cells in vitro.

The king is dead, long live the king: entering a new era of stem cell research and clinical development.

PubMed

Ichim, Thomas; Riordan, Neil H; Stroncek, David F

2011-12-20

In mid November the biopharma industry was shocked by the announcement from Geron that they were ending work on embryonic stem cell research and therapy. For more than 10 years the public image of all stem cell research has been equated with embryonic stem cells. Unfortunately, a fundamentally important medical and financial fact was being ignored: embryonic stem cell therapy is extremely immature. In parallel to efforts in embryonic stem cell research and development, scientists and physicians in the field of adult stem cells realized that the natural role of adult stem cells in the body is to promote healing and to act like endogenous "repair cells" and, as a result, numerous companies have entered the field of adult stem cell therapy with the goal of expanding numbers of adult stem cells for administration to patients with various conditions. In contrast to embryonic stem cells, which are extremely expensive and potentially dangerous, adult cell cells are inexpensive and have an excellent safety record when used in humans. Many studies are now showing that adult stem cells are practical, patient-applicable, therapeutics that are very close to being available for incorporation into the practice of medicine. These events signal the entrance of the field of stem cells into a new era: an era where hype and misinformation no longer triumph over economic and medical realities.

Human Embryonic Stem Cell Therapy in Crohn’s Disease: A Case Report

PubMed Central

Shroff, Geeta

2016-01-01

Patient: Male, 21 Final Diagnosis: Crohn’s disease Symptoms: Intolerance to specific foods • abdominal pain and diarrhea Medication: Human embryonic stem cell therapy Clinical Procedure: Human embryonic stem cell transplantation Specialty: Gastroenterology Objective: Unusual or unexpected effect of treatment Background: Crohn’s disease is a chronic inflammatory disease of the intestines, mainly the colon and ileum, related with ulcers and fistulae. It is estimated to affect 565 000 people in the United States. Currently available therapies, such as antibiotics, thiopurines, and anti-tumor necrosis factor-alpha agents, are only observed to reduce the complications associated with Crohn’s disease and to improve quality of life, but cannot cure the disease. Stem cell therapy appears to have certain advantages over conventional therapies. Our study aimed to evaluate the efficacy of human embryonic stem cell therapy in a patient with Crohn’s disease. Case Report: A 21-year-old male with chief complaints of intolerance to specific foods, abdominal pain, and diarrhea underwent human embryonic stem cell therapy for two months. After undergoing human embryonic stem cell therapy, the patient showed symptomatic relief. He had no complaints of back pain, abdominal pain, or diarrhea and had improved digestion. The patient had no signs and symptoms of skin infection, and had improved limb stamina, strength, and endurance. The condition of patient was stable after the therapy. Conclusions: Human embryonic stem cell therapy might serve as a new optimistic treatment approach for Crohn’s disease. PMID:26923312

GENOMIC ADAPTATION OF THE EMBRYONIC STEM CELL TEST (EST) FOR A TOXICOLOGICAL STUDY OF DRINKING WATER DISINFECTION BY-PRODUCTS

EPA Science Inventory

Among the many promised and potential applications of embryonic stem cells, in vitro toxicology is one area in which ES cells have already proven their utility. In 2003, the Embryonic Stem Cell Test (EST) protocol was validated in Europe as an in vitro alternative to live animal...

Development of an invitro technique to use mouse embryonic stem cell in evaluating effects of xenobiotics

EPA Science Inventory

Our goal has been to develop a high-throughput, in vitro technique for evaluating the effects of xenobiotics using mouse embryonic stem cells (mESCs). We began with the Embryonic Stem Cell Test (EST), which is used to predict the embryotoxic potential of a test compound by combin...

A monoclonal antibody recognizes undifferentiation-specific carbohydrate moieties expressed on cell surface of the human dental pulp cells.

PubMed

Kang, Kyung-Jung; Ko, Seon-Yle; Ryu, Chun-Jeih; Jang, Young-Joo

2017-05-01

Human dental pulp cells are obtained from dental pulp tissue, and have the ability to form dentin and a pulp-like complex. Although adult stem cells have been identified from the primary culture by using specific cell surface markers, the identity of surface markers for the purification of stem cells within the dental pulp population are still unclear. Previously, we had constructed monoclonal antibodies against the undifferentiated cell-specific surface markers of human dental pulp cells (hDPCs) by performing decoy immunization. Among them, a monoclonal antibody against the cell surface antigen of the undifferentiated hDPCs (named UPSA-1) was purified and its heavy and light chain consensus regions were analyzed. The cell surface binding affinity of UPSA-1 mAb on the undifferentiated hDPCs was stronger than that on the differentiated cells. When tunicamycin was applied to hDPSCs during culture, the cell surface binding affinity of the antibody was dramatically decreased, and dentinogenic differentiation was reduced. The purified UPSA-1 antigen band resulting from immunoprecipitation disappeared or shifted down on the SDS-PAGE by deglycosylation. These data suggested that glycosylation on the cell surface might be a marker of an undifferentiated state, and that UPSA-1 mAb might be useful for identifying the carbohydrate moiety on the cell surface of undifferentiated pulp cells. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Pathological modifications of plant stem cell destiny

USDA-ARS?s Scientific Manuscript database

In higher plants, the shoot apex contains undifferentiated stem cells that give rise to various tissues and organs. The fate of these stem cells determines the pattern of plant growth as well as reproduction; and such fate is genetically preprogrammed. We found that a bacterial infection can derai...

Embryonic Stem Cell Patents and Human Dignity

PubMed Central

Resnik, David B.

2009-01-01

This article examines the assertion that human embryonic stem cells patents are immoral because they violate human dignity. After analyzing the concept of human dignity and its role in bioethics debates, this article argues that patents on human embryos or totipotent embryonic stem cells violate human dignity, but that patents on pluripotent or multipotent stem cells do not. Since patents on pluripotent or multipotent stem cells may still threaten human dignity by encouraging people to treat embryos as property, patent agencies should carefully monitor and control these patents to ensure that patents are not inadvertently awarded on embryos or totipotent stem cells. PMID:17922198

Embryonic death and the creation of human embryonic stem cells.

PubMed

Landry, Donald W; Zucker, Howard A

2004-11-01

The creation of human embryonic stem cells through the destruction of a human embryo pits the value of a potential therapeutic tool against that of an early human life. This contest of values has resulted in a polarized debate that neglects areas of common interest and perspective. We suggest that a common ground for pursuing research on human embryonic stem cells can be found by reconsidering the death of the human embryo and by applying to this research the ethical norms of essential organ donation.

Embryonic stem cells improve skeletal muscle recovery after extreme atrophy in mice.

PubMed

Artioli, Guilherme Giannini; De Oliveira Silvestre, João Guilherme; Guilherme, João Paulo Limongi França; Baptista, Igor Luchini; Ramos, Gracielle Vieira; Da Silva, Willian José; Miyabara, Elen Haruka; Moriscot, Anselmo Sigari

2015-03-01

We injected embryonic stem cells into mouse tibialis anterior muscles subjected to botulinum toxin injections as a model for reversible neurogenic atrophy. Muscles were exposed to botulinum toxin for 4 weeks and allowed to recover for up to 6 weeks. At the onset of recovery, a single muscle injection of embryonic stem cells was administered. The myofiber cross-sectional area, single twitch force, peak tetanic force, time-to-peak force, and half-relaxation time were determined. Although the stem cell injection did not affect the myofiber cross-sectional area gain in recovering muscles, most functional parameters improved significantly compared with those of recovering muscles that did not receive the stem cell injection. Muscle function recovery was accelerated by embryonic stem cell delivery in this durable neurogenic atrophy model. We conclude that stem cells should be considered a potential therapeutic tool for recovery after extreme skeletal muscle atrophy. © 2014 Wiley Periodicals, Inc.

A Scalable System for Production of Functional Pancreatic Progenitors from Human Embryonic Stem Cells

PubMed Central

Schulz, Thomas C.; Young, Holly Y.; Agulnick, Alan D.; Babin, M. Josephine; Baetge, Emmanuel E.; Bang, Anne G.; Bhoumik, Anindita; Cepa, Igor; Cesario, Rosemary M.; Haakmeester, Carl; Kadoya, Kuniko; Kelly, Jonathan R.; Kerr, Justin; Martinson, Laura A.; McLean, Amanda B.; Moorman, Mark A.; Payne, Janice K.; Richardson, Mike; Ross, Kelly G.; Sherrer, Eric S.; Song, Xuehong; Wilson, Alistair Z.; Brandon, Eugene P.; Green, Chad E.; Kroon, Evert J.; Kelly, Olivia G.; D’Amour, Kevin A.; Robins, Allan J.

2012-01-01

Development of a human embryonic stem cell (hESC)-based therapy for type 1 diabetes will require the translation of proof-of-principle concepts into a scalable, controlled, and regulated cell manufacturing process. We have previously demonstrated that hESC can be directed to differentiate into pancreatic progenitors that mature into functional glucose-responsive, insulin-secreting cells in vivo. In this study we describe hESC expansion and banking methods and a suspension-based differentiation system, which together underpin an integrated scalable manufacturing process for producing pancreatic progenitors. This system has been optimized for the CyT49 cell line. Accordingly, qualified large-scale single-cell master and working cGMP cell banks of CyT49 have been generated to provide a virtually unlimited starting resource for manufacturing. Upon thaw from these banks, we expanded CyT49 for two weeks in an adherent culture format that achieves 50–100 fold expansion per week. Undifferentiated CyT49 were then aggregated into clusters in dynamic rotational suspension culture, followed by differentiation en masse for two weeks with a four-stage protocol. Numerous scaled differentiation runs generated reproducible and defined population compositions highly enriched for pancreatic cell lineages, as shown by examining mRNA expression at each stage of differentiation and flow cytometry of the final population. Islet-like tissue containing glucose-responsive, insulin-secreting cells was generated upon implantation into mice. By four- to five-months post-engraftment, mature neo-pancreatic tissue was sufficient to protect against streptozotocin (STZ)-induced hyperglycemia. In summary, we have developed a tractable manufacturing process for the generation of functional pancreatic progenitors from hESC on a scale amenable to clinical entry. PMID:22623968

Determination of Protein Interactome of Transcription Factor Sox2 in Embryonic Stem Cells Engineered for Inducible Expression of Four Reprogramming Factors*

PubMed Central

Gao, Zhiguang; Cox, Jesse L.; Gilmore, Joshua M.; Ormsbee, Briana D.; Mallanna, Sunil K.; Washburn, Michael P.; Rizzino, Angie

2012-01-01

Unbiased proteomic screens provide a powerful tool for defining protein-protein interaction networks. Previous studies employed multidimensional protein identification technology to identify the Sox2-interactome in embryonic stem cells (ESC) undergoing differentiation in response to a small increase in the expression of epitope-tagged Sox2. Thus far the Sox2-interactome in ESC has not been determined. To identify the Sox2-interactome in ESC, we engineered ESC for inducible expression of different combinations of epitope-tagged Sox2 along with Oct4, Klf4, and c-Myc. Epitope-tagged Sox2 was used to circumvent the lack of suitable Sox2 antibodies needed to perform an unbiased proteomic screen of Sox2-associated proteins. Although i-OS-ESC differentiate when both Oct4 and Sox2 are elevated, i-OSKM-ESC do not differentiate even when the levels of the four transcription factors are coordinately elevated ∼2–3-fold. Our findings with i-OS-ESC and i-OSKM-ESC provide new insights into the reasons why ESC undergo differentiation when Sox2 and Oct4 are elevated in ESC. Importantly, the use of i-OSKM-ESC enabled us to identify the Sox2-interactome in undifferentiated ESC. Using multidimensional protein identification technology, we identified >70 proteins that associate with Sox2 in ESC. We extended these findings by testing the function of the Sox2-assoicated protein Smarcd1 and demonstrate that knockdown of Smarcd1 disrupts the self-renewal of ESC and induces their differentiation. Together, our work provides the first description of the Sox2-interactome in ESC and indicates that Sox2 along with other master regulators is part of a highly integrated protein-protein interaction landscape in ESC. PMID:22334693

SC1 Promotes MiR124-3p Expression to Maintain the Self-Renewal of Mouse Embryonic Stem Cells by Inhibiting the MEK/ERK Pathway.

PubMed

Wei, Qing; Liu, Hongliang; Ai, Zhiying; Wu, Yongyan; Liu, Yingxiang; Shi, Zhaopeng; Ren, Xuexue; Guo, Zekun

2017-01-01

Self-renewal is one of the most important features of embryonic stem (ES) cells. SC1 is a small molecule modulator that effectively maintains the self-renewal of mouse ES cells in the absence of leukemia inhibitory factor (LIF), serum and feeder cells. However, the mechanism by which SC1 maintains the undifferentiated state of mouse ES cells remains unclear. In this study, microarray and small RNA deep-sequencing experiments were performed on mouse ES cells treated with or without SC1 to identify the key genes and microRNAs that contributed to self-renewal. SC1 regulates the expressions of pluripotency and differentiation factors, and antagonizes the retinoic acid (RA)-induced differentiation in the presence or absence of LIF. SC1 inhibits the MEK/ERK pathway through Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and pathway reporting experiments. Small RNA deep-sequencing revealed that SC1 significantly modulates the expression of multiple microRNAs with crucial functions in ES cells. The expression of miR124-3p is upregulated in SC1-treated ES cells, which significantly inhibits the MEK/ERK pathway by targeting Grb2, Sos2 and Egr1. SC1 enhances the self-renewal capacity of mouse ES cells by modulating the expression of key regulatory genes and pluripotency-associated microRNAs. SC1 significantly upregulates miR124-3p expression to further inhibit the MEK/ ERK pathway by targeting Grb2, Sos2 and Egr1. © 2017 The Author(s). Published by S. Karger AG, Basel.

Differentiation of monkey embryonic stem cells to hepatocytes by feeder-free dispersion culture and expression analyses of cytochrome p450 enzymes responsible for drug metabolism.

PubMed

Maruyama, Junya; Matsunaga, Tamihide; Yamaori, Satoshi; Sakamoto, Sakae; Kamada, Noboru; Nakamura, Katsunori; Kikuchi, Shinji; Ohmori, Shigeru

2013-01-01

We reported previously that monkey embryonic stem cells (ESCs) were differentiated into hepatocytes by formation of embryoid bodies (EBs). However, this EB formation method is not always efficient for assays using a large number of samples simultaneously. A dispersion culture system, one of the differentiation methods without EB formation, is able to more efficiently provide a large number of feeder-free undifferentiated cells. A previous study demonstrated the effectiveness of the Rho-associated kinase inhibitor Y-27632 for feeder-free dispersion culture and induction of differentiation of monkey ESCs into neural cells. In the present study, the induction of differentiation of cynomolgus monkey ESCs (cmESCs) into hepatocytes was performed by the dispersion culture method, and the expression and drug inducibility of cytochrome P450 (CYP) enzymes in these hepatocytes were examined. The cmESCs were successfully differentiated into hepatocytes under feeder-free dispersion culture conditions supplemented with Y-27632. The hepatocytes differentiated from cmESCs expressed the mRNAs for three hepatocyte marker genes (α-fetoprotein, albumin, CYP7A1) and several CYP enzymes, as measured by real-time polymerase chain reaction. In particular, the basal expression of cmCYP3A4 (3A8) in these hepatocytes was detected at mRNA and enzyme activity (testosterone 6β-hydroxylation) levels. Furthermore, the expression and activity of cmCYP3A4 (3A8) were significantly upregulated by rifampicin. These results indicated the effectiveness of Y-27632 supplementation for feeder-free dispersed culture and induction of differentiation into hepatocytes, and the expression of functional CYP enzyme(s) in cmESC-derived hepatic cells.

Transplantation of reprogrammed embryonic stem cells improves visual function in a mouse model for retinitis pigmentosa.

PubMed

Wang, Nan-Kai; Tosi, Joaquin; Kasanuki, Jennifer Mie; Chou, Chai Lin; Kong, Jian; Parmalee, Nancy; Wert, Katherine J; Allikmets, Rando; Lai, Chi-Chun; Chien, Chung-Liang; Nagasaki, Takayuki; Lin, Chyuan-Sheng; Tsang, Stephen H

2010-04-27

To study whether C57BL/6J-Tyr/J (C2J) mouse embryonic stem (ES) cells can differentiate into retinal pigment epithelial (RPE) cells in vitro and then restore retinal function in a model for retinitis pigmentosa: Rpe65/Rpe65 C57BL6 mice. Yellow fluorescent protein (YFP)-labeled C2J ES cells were induced to differentiate into RPE-like structures on PA6 feeders. RPE-specific markers are expressed from differentiated cells in vitro. After differentiation, ES cell-derived RPE-like cells were transplanted into the subretinal space of postnatal day 5 Rpe65/Rpe65 mice. Live imaging of YFP-labeled C2J ES cells demonstrated survival of the graft. Electroretinograms (ERGs) were performed on transplanted mice to evaluate the functional outcome of transplantation. RPE-like cells derived from ES cells sequentially express multiple RPE-specific markers. After transplantation, YFP-labeled cells can be tracked with live imaging for as long as 7 months. Although more than half of the mice were complicated with retinal detachments or tumor development, one fourth of the mice showed increased electroretinogram responses in the transplanted eyes. Rpe65/Rpe65 mice transplanted with RPE-like cells showed significant visual recovery during a 7-month period, whereas those injected with saline, PA6 feeders, or undifferentiated ES cells showed no rescue. ES cells can differentiate, morphologically, and functionally, into RPE-like cells. Based on these findings, differentiated ES cells have the potential for the development of new therapeutic approaches for RPE-specific diseases such as certain forms of retinitis pigmentosa and macular degeneration. Nevertheless, stringent control of retinal detachment and teratoma development will be necessary before initiation of treatment trials.

Importance of a diffusion-dominant small volume to activate cell-secreted soluble factor signaling in embryonic stem cell culture in microbioreactors: a mathematical model based study.

PubMed

Chowdhury, Mohammad Mahfuz; Fujii, Teruo; Sakai, Yasuyuki

2013-07-01

In our previous studies, we observed that cell-secreted BMP4 had a prominent influence on mouse embryonic stem cell (mESC) behaviors in a membrane-based two-chambered microbioreactor (MB), but not in a macro-scale culture (6-well plate/6WP). In this study, we investigated how the physical aspects of these cultures regulated BMP4 signaling by developing mathematical models of the cultures. The models estimated signaling activity in the cultures by considering size of the undifferentiated mESC colonies and their growth, diffusion of BMP4, and BMP4 trafficking process in the colonies. The models successfully depicted measured profile of BMP4 concentration in the culture medium which was two times higher in the MB than that in the 6WP during 5-day culture. The models estimated that, owing to the small volume and the membrane, cells were exposed to a higher BMP4 concentration in the top chamber of the MB than that in the 6WP culture. The higher concentration of BMP4 induced a higher concentration of BMP4-bound receptor in the colony in the MB than in the 6WP, thereby leading to the higher activation of BMP4 signaling in the MB. The models also predicted that the size of the MB, but not that of the 6WP, was suitable for maximizing BMP4 accumulation and upregulating its signaling. This study will be helpful in analyzing culture systems, designing microfluidic devices for controlling ESC or other cell behavior. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Role of Nitric Oxide Signaling in Endothelial Differentiation of Embryonic Stem Cells

PubMed Central

Huang, Ngan F.; Fleissner, Felix; Sun, John

2010-01-01

Signaling pathways that govern embryonic stem cell (ESCs) differentiation are not well characterized. Nitric oxide (NO) is a potent vasodilator that modulates other signaling pathways in part by activating soluble guanylyl cyclase (sGC) to produce cyclic guanosine monophosphate (cGMP). Because of its importance in endothelial cell (EC) growth in the adult, we hypothesized that NO may play a critical role in EC development. Accordingly, we assessed the role of NO in ESC differentiation into ECs. Murine ESCs differentiated in the presence of NO synthase (NOS) inhibitor NG-nitroarginine methyl ester (l-NAME) for up to 11 days were not significantly different from vehicle-treated cells in EC markers. However, by 14 days, l-NAME-treated cells manifested modest reduction in EC markers CD144, FLK1, and endothelial NOS. ESC-derived ECs generated in the presence of l-NAME exhibited reduced tube-like formation in Matrigel. To understand the discrepancy between early and late effects of l-NAME, we assessed the NOS machinery and observed low mRNA expression of NOS and sGC subunits in ESCs, compared to differentiating cells after 14 days. In response to NO donors or activation of NOS or sGC, cellular cGMP levels were undetectable in undifferentiated ESCs, at low levels on day 7, and robustly increased in day 14 cells. Production of cGMP upon NOS activation at day 14 was inhibited by l-NAME, confirming endogenous NO dependence. Our data suggest that NOS elements are present in ESCs but inactive until later stages of differentiation, during which period NOS inhibition reduces expression of EC markers and impairs angiogenic function. PMID:20064011

[The use of embryonic stem cells for medical-therapeutical purposes: a study of attitudes among Icelandic physicians, lawyers and clergymen.].

PubMed

Oskarsson, Trausti; Guðmundsson, Flóki; Sigurðsson, Jóhann Agúst; Getz, Linn; Arnason, Vilhjálmur

2003-06-01

To study the bioethical standpoints among three groups of Icelandic professionals in relation to the use of embryonic stem cells for medical-therapeutical purposes. In June 2002, a questionnaire was sent by mail to a random sample of 284 doctors and 293 lawyers, as well as all 168 practicing clergymen in Iceland. The participants' position in relation to the use of embryonic stem cells for therapeutical purposes was elicited through general questions as well as case examples. 290 questionnaires (39%) were returned. 62% of participants believed the embryo to have an ethical status superior to that of biologically comparable life forms. 20% of respondents considered its status as equal to that of a grown human being, whilst 18% considered it equal to biologically comparable primitive life forms. There was a difference between the respondent groups (p<0,05). A vast majority believed the use of embryonic stem cells for therapeutical purposes to be justifiable, although the origin of the stem cells appeared to make a difference to many respondents. 8% of participants took an unconditional position against the use of embryonic stem cells. Among those who considered the use of embryonic stem cells with a therapeutic aim to be justifiable, 71% believed that embryonic stem cells should only be utilized to treat diseases of a severe nature. 64% of participants defended the idea of therapeutic cloning with the intention to treat a patient with Parkinson's disease, but the case history elicited considerable difference between professional groups. Clergymen and lawyers tended to hold firmer attitudes, clergymen against and lawyers for the use of stem cells, whilst medical doctors as a group positioned themselves more towards the middle. Female respondents generally took a more modest stand whilst males were more likely to take a firmer stand in both directions. A vast majority (87%) of the participants believed there to be a need for public debate in relation to the use of embryonic stem cells for therapeutical purposes. Overall, participants views in relation to the use of embryonic stem cells for medical purposes were rather liberal. There were however significant differences between professional groups. The relatively high tolerance in regard to therapeutic cloning is interesting in view of the considerable controversy over this topic in many countries. There appears to be fertile ground for a public debate about the use of embryonic stem cells for medical purposes in Iceland.

β2-Microglobulin as a potential factor for the expansion of mesenchymal stem cells

PubMed Central

Zhu, Ying; Su, Yongping; Cheng, Tianmin; Chung, Leland W. K.

2010-01-01

Multipotent mesenchymal stem cells (MSCs) hold great promise in regenerative medicine, but one of the biggest challenges facing for their application is the ex vivo expansion to obtain enough undifferentiated cells. Fetal bovine serum (FBS), which can elicit possible contaminations of prion, virus, zoonosis or immunological reaction against xenogenic serum antigens, still remains essential to the culture formulations. There is an urgent need to identify potential factors for the undifferentiated expansion of MSCs to reduce the use of FBS or eventually replace it. A previously recognized housekeeping gene, β2-microglobulin (β2M), is demonstrated to act as a novel growth factor to stimulate the undifferentiated ex vivo expansion and preserve the pluripotency of adult MSCs from various sources. The use of β2M might have promising implications for future clinical application of MSCs. PMID:19466557

Placenta-an alternative source of stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matikainen, Tiina; Laine, Jarmo

2005-09-01

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 ismore » 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.« less

78 FR 13688 - Proposed Collection; 60-Day Comment Request: Request for Human Embryonic Stem Cell Line To Be...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-28

... Comment Request: Request for Human Embryonic Stem Cell Line To Be Approved for Use in NIH Funded Research... Embryonic Stem Cell Line to be Approved for Use in NIH Funded Research. OMB No. 0925-0601-- Expiration Date... cell lines be approved for use in NIH funded research. Applicants may submit applications at any time...

Patently controversial: markets, morals, and the President's proposal for embryonic stem cell research.

PubMed

Fins, Joseph J; Schachter, Madeleine

2002-09-01

This essay considers the implications of President George W. Bush's proposal for human embryonic stem cell research. Through the perspective of patent law, privacy, and informed consent, we elucidate the ongoing controversy about the moral standing of human embryonic stem cells and their derivatives and consider how the inconsistencies in the president's proposal will affect clinical practice and research.

Paradoxical Role of DNA Methylation in Activation of FoxA2 Gene Expression during Endoderm Development*

PubMed Central

Bahar Halpern, Keren; Vana, Tal; Walker, Michael D.

2014-01-01

The transcription factor FoxA2 is a master regulator of endoderm development and pancreatic beta cell gene expression. To elucidate the mechanisms underlying the activation of the FoxA2 gene during differentiation, we have compared the epigenetic status of undifferentiated human embryonic stem cells (hESCs), hESC-derived early endoderm stage cells (CXCR4+ cells), and pancreatic islet cells. Unexpectedly, a CpG island in the promoter region of the FoxA2 gene displayed paradoxically high levels of DNA methylation in expressing tissues (CXCR4+, islets) and low levels in nonexpressing tissues. This CpG island region was found to repress reporter gene expression and bind the Polycomb group protein SUZ12 and the DNA methyltransferase (DNMT)3b preferentially in undifferentiated hESCs as compared with CXCR4+ or islets cells. Consistent with this, activation of FoxA2 gene expression, but not CXCR4 or SOX17, was strongly inhibited by 5-aza-2′-deoxycytidine and by knockdown of DNMT3b. We hypothesize that in nonexpressing tissues, the lack of DNA methylation allows the binding of DNA methyltransferases and repressing proteins, such as Polycomb group proteins; upon differentiation, DNMT activation leads to CpG island methylation, causing loss of repressor protein binding. These results suggest a novel and unexpected role for DNA methylation in the activation of FoxA2 gene expression during differentiation. PMID:25016019

A Simple and Robust Method for Culturing Human-Induced Pluripotent Stem Cells in an Undifferentiated State Using Botulinum Hemagglutinin.

PubMed

Kim, Mee-Hae; Matsubara, Yoshifumi; Fujinaga, Yukako; Kino-Oka, Masahiro

2018-02-01

Clinical and industrial applications of human-induced pluripotent stem cells (hiPSCs) is hindered by the lack of robust culture strategies capable of sustaining a culture in an undifferentiated state. Here, a simple and robust hiPSC-culture-propagation strategy incorporating botulinum hemagglutinin (HA)-mediated selective removal of cells deviating from an undifferentiated state is developed. After HA treatment, cell-cell adhesion is disrupted, and deviated cells detached from the central region of the colony to subsequently form tight monolayer colonies following prolonged incubation. The authors find that the temporal and dose-dependent activity of HA regulated deviated-cell removal and recoverability after disruption of cell-cell adhesion in hiPSC colonies. The effects of HA are confirmed under all culture conditions examined, regardless of hiPSC line and feeder-dependent or -free culture conditions. After routine application of our HA-treatment paradigm for serial passages, hiPSCs maintains expression of pluripotent markers and readily forms embryoid bodies expressing markers for all three germ-cell layers. This method enables highly efficient culturing of hiPSCs and use of entire undifferentiated portions without having to pick deviated cells manually. This simple and readily reproducible culture strategy is a potentially useful tool for improving the robust and scalable maintenance of undifferentiated hiPSC cultures. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Integration of immunological aspects in the European Human Embryonic Stem Cell Registry.

PubMed

Borstlap, Joeri; Kurtz, Andreas

2008-05-01

The immunological properties of stem cells are of increasing importance in regenerative medicine. Immunomodulatory mechanisms seem to play an important role not only with respect to the understanding of underlying mechanisms of autologous versus allogenic therapeutic approaches, but also for endogeneous tissue regeneration. The newly established European human embryonic stem cell registry (hESCreg) offers an international database for the registration, documentation and characterisation of human embryonic stem cells (hESC) and their use. By doing so, hESCreg aims to develop a model procedure for further standardisation efforts in the field of stem cell research and regenerative medicine, and eventually the registry may lead to a repository of therapy-related information. Currently the stem cell characterisation data acquired by the registry are divided into several categories such as cell derivation, culture conditions, genetic constitution, stem cell marker expression and degree of modification. This article describes immunological aspects of stem cell characterisation and explores the layout and relevance of a possible additional section to the hESCreg repository to include immunological characteristics of human embryonic stem cells.

The proliferative and chronotropic effects of Brillantaisia nitens Lindau (Acanthaceae) extracts on pluripotent stem cells and their cardiomyocytes derivatives.

PubMed

Nembo, Erastus Nembu; Dimo, Theophile; Bopda, Orelien Sylvain Mtopi; Hescheler, Jürgen; Nguemo, Filomain

2014-10-28

Brillantaisia nitens Lindau (Acanthaceae) leaves are commonly used in traditional medicine in Africa for the treatment of many disorders including heart diseases and malaria. In this study, we therefore evaluated the effect of the methylene chloride/methanol leaf extract of Brillantaisia nitens on the proliferation of mouse pluripotent stem cells and their cardiomyocyte derivatives. In this study, we combined two emerging technologies, pluripotent stem cell-derived cardiomyocytes and modern electrophysiology systems (impedance-based real-time) to assess the cytotoxicity of Brillantaisia nitens extract (BNE). Undifferentiated pluripotent cells and cardiomyocytes were exposed to different concentrations of BNE. Cell viability and contraction were monitored by impedance using the xCELLigence system for short- and long-term treatment whereas the excitability of single cardiomyocytes was captured by patch clamp technique after BNE acute exposure. Brillantaisia nitens extract inhibited the proliferation and increased cytotoxicity of embryonic stem cells in a concentration-dependent manner. With the increase in concentration of BNE, beating rate and the contractile amplitude of cardiomyocytes changed significantly. Spontaneous rhythmic activity of cardiomyocytes was completely suppressed after 48 and 24h exposures to relatively low (4.16 mg/ml) and high (8.32 mg/ml) concentrations of BNE, respectively. Moreover, acute application of 4.16 mg/ml of BNE led to a significant alteration of action potential (AP) parameters such as beating frequency, amplitude and AP duration at 90% of repolarization. Brillantaisia nitens extract inhibits the proliferative capacity of pluripotent stem cells and reduces electrical activity of cardiomyocytes, confirming its depressant action on the heart. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Drosophila E-Cadherin Functions in Hematopoietic Progenitors to Maintain Multipotency and Block Differentiation

PubMed Central

Gao, Hongjuan; Wu, Xiaorong; Fossett, Nancy

2013-01-01

A fundamental question in stem cell biology concerns the regulatory strategies that control the choice between multipotency and differentiation. Drosophila blood progenitors or prohemocytes exhibit key stem cell characteristics, including multipotency, quiescence, and niche dependence. As a result, studies of Drosophila hematopoiesis have provided important insights into the molecular mechanisms that control these processes. Here, we show that E-cadherin is an important regulator of prohemocyte fate choice, maintaining prohemocyte multipotency and blocking differentiation. These functions are reminiscent of the role of E-cadherin in mammalian embryonic stem cells. We also show that mis-expression of E-cadherin in differentiating hemocytes disrupts the boundary between these cells and undifferentiated prohemocytes. Additionally, upregulation of E-cadherin in differentiating hemocytes increases the number of intermediate cell types expressing the prohemocyte marker, Patched. Furthermore, our studies indicate that the Drosophila GATA transcriptional co-factor, U-shaped, is required for E-cadherin expression. Consequently, E-cadherin is a downstream target of U-shaped in the maintenance of prohemocyte multipotency. In contrast, we showed that forced expression of the U-shaped GATA-binding partner, Serpent, repressed E-cadherin expression and promoted lamellocyte differentiation. Thus, U-shaped may maintain E-cadherin expression by blocking the inhibitory activity of Serpent. Collectively, these observations suggest that GATA:FOG complex formation regulates E-cadherin levels and, thereby, the choice between multipotency and differentiation. The work presented in this report further defines the molecular basis of prohemocyte cell fate choice, which will provide important insights into the mechanisms that govern stem cell biology. PMID:24040319

Human Decidua-Derived Mesenchymal Cells Are a Promising Source for the Generation and Cell Banking of Human Induced Pluripotent Stem Cells

PubMed Central

Shofuda, Tomoko; Kanematsu, Daisuke; Fukusumi, Hayato; Yamamoto, Atsuyo; Bamba, Yohei; Yoshitatsu, Sumiko; Suemizu, Hiroshi; Nakamura, Masato; Sugimoto, Yoshikazu; Furue, Miho Kusuda; Kohara, Arihiro; Akamatsu, Wado; Okada, Yohei; Okano, Hideyuki; Yamasaki, Mami; Kanemura, Yonehiro

2013-01-01

Placental tissue is a biomaterial with remarkable potential for use in regenerative medicine. It has a three-layer structure derived from the fetus (amnion and chorion) and the mother (decidua), and it contains huge numbers of cells. Moreover, placental tissue can be collected without any physical danger to the donor and can be matched with a variety of HLA types. The decidua-derived mesenchymal cells (DMCs) are highly proliferative fibroblast-like cells that express a similar pattern of CD antigens as bone marrow-derived mesenchymal cells (BM-MSCs). Here we demonstrated that induced pluripotent stem (iPS) cells could be efficiently generated from DMCs by retroviral transfer of reprogramming factor genes. DMC-hiPS cells showed equivalent characteristics to human embryonic stem cells (hESCs) in colony morphology, global gene expression profile (including human pluripotent stem cell markers), DNA methylation status of the OCT3/4 and NANOG promoters, and ability to differentiate into components of the three germ layers in vitro and in vivo. The RNA expression of XIST and the methylation status of its promoter region suggested that DMC-iPSCs, when maintained undifferentiated and pluripotent, had three distinct states: (1) complete X-chromosome reactivation, (2) one inactive X-chromosome, or (3) an epigenetic aberration. Because DMCs are derived from the maternal portion of the placenta, they can be collected with the full consent of the adult donor and have considerable ethical advantages for cell banking and the subsequent generation of human iPS cells for regenerative applications. PMID:26858858

Response to: Dittrich et al.: Non-Embryo-Destructive Extraction of Pluripotent Embryonic Stem Cells – Overlooked Legal Prohibitions, Professional Legal Consequences and Inconsistencies in Patent Law

PubMed Central

Faltus, T.; Storz, U.

2016-01-01

The publication of “Non-embryo-destructive Extraction of Pluripotent Embryonic Stem Cells: Implications for Regenerative Medicine and Reproductive Medicine” by Dittrich et al. in Geburtshilfe und Frauenheilkunde 2015; 75: 1239–1242 1 describes various possibilities which could result from the non-embryo-destructive extraction of embryonic stem cells from human blastocysts. But implementing this method is more problematic, both legally and ethically, than the authors have represented it to be and is illegal in Germany. German patent DE 10 2004 062 184 on the non-embryo-destructive extraction of embryonic stem cells referred to by Dittrich et al. contravenes the higher-ranking case-law of the European Court of Justice. Ultimately, the non-embryo-destructive harvesting of embryonic stem cells with the aim of storing these cells for use in potential therapies as proposed by Dittrich et al. is prohibited in Germany and could lead to criminal prosecution. PMID:28094826

Transcriptional Profiling of Ectoderm Specification to Keratinocyte Fate in Human Embryonic Stem Cells

PubMed Central

Tadeu, Ana Mafalda Baptista; Lin, Samantha; Hou, Lin; Chung, Lisa; Zhong, Mei; Zhao, Hongyu; Horsley, Valerie

2015-01-01

In recent years, several studies have shed light into the processes that regulate epidermal specification and homeostasis. We previously showed that a broad-spectrum γ–secretase inhibitor DAPT promoted early keratinocyte specification in human embryonic stem cells triggered to undergo ectoderm specification. Here, we show that DAPT accelerates human embryonic stem cell differentiation and induces expression of the ectoderm protein AP2. Furthermore, we utilize RNA sequencing to identify several candidate regulators of ectoderm specification including those involved in epithelial and epidermal development in human embryonic stem cells. Genes associated with transcriptional regulation and growth factor activity are significantly enriched upon DAPT treatment during specification of human embryonic stem cells to the ectoderm lineage. The human ectoderm cell signature identified in this study contains several genes expressed in ectodermal and epithelial tissues. Importantly, these genes are also associated with skin disorders and ectodermal defects, providing a platform for understanding the biology of human epidermal keratinocyte development under diseased and homeostatic conditions. PMID:25849374

Human embryonic stem cell-derived pancreatic endoderm alleviates diabetic pathology and improves reproductive outcome in C57BL/KsJ-Lep(db/+) gestational diabetes mellitus mice.

PubMed

Xing, Baoheng; Wang, Lili; Li, Qin; Cao, Yalei; Dong, Xiujuan; Liang, Jun; Wu, Xiaohua

2015-07-01

Gestational diabetes mellitus is a condition commonly encountered during mid to late pregnancy with pathologic manifestations including hyperglycemia, hyperinsulinemia, insulin resistance, and fetal maldevelopment. The cause of gestational diabetes mellitus can be attributed to both genetic and environmental factors, hence complicating its diagnosis and treatment. Pancreatic progenitors derived from human embryonic stem cells were shown to be able to effectively treat diabetes in mice. In this study, we have developed a system of treating diabetes using human embryonic stem cell-derived pancreatic endoderm in a mouse model of gestational diabetes mellitus. Human embryonic stem cells were differentiated in vitro into pancreatic endoderm, which were then transplanted into db/+ mice suffering from gestational diabetes mellitus. The transplant greatly improved glucose metabolism and reproductive outcome of the females compared with the control groups. Our findings support the feasibility of using differentiated human embryonic stem cells for treating gestational diabetes mellitus patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Human embryonic stem cells and good manufacturing practice: Report of a 1- day workshop held at Stem Cell Biology Research Center, Yazd, 27th April 2017.

PubMed

Akyash, Fatemeh; Sadeghian-Nodoushan, Fatemeh; Tahajjodi, Somayyeh Sadat; Nikukar, Habib; Farashahi Yazd, Ehsan; Azimzadeh, Mostafa; D Moore, Harry; Aflatoonian, Behrouz

2017-05-01

This report explains briefly the minutes of a 1-day workshop entitled; "human embryonic stem cells (hESCs) and good manufacturing practice (GMP)" held by Stem Cell Biology Research Center based in Yazd Reproductive Sciences Institute at Shahid Sadoughi University of Medical Sciences, Yazd, Iran on 27 th April 2017. In this workshop, in addition to the practical sessions, Prof. Harry D. Moore from Centre for Stem Cell Biology, University of Sheffield, UK presented the challenges and the importance of the biotechnology of clinical-grade human embryonic stem cells from first derivation to robust defined culture for therapeutic applications.

Strand displacement amplification for ultrasensitive detection of human pluripotent stem cells.

PubMed

Wu, Wei; Mao, Yiping; Zhao, Shiming; Lu, Xuewen; Liang, Xingguo; Zeng, Lingwen

2015-06-30

Human pluripotent stem cells (hPSCs), such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), provide a powerful model system for studies of cellular identity and early mammalian development, which hold great promise for regenerative medicine. It is necessary to develop a convenient method to discriminate hPSCs from other cells in clinics and basic research. Herein, a simple and reliable biosensor for stem cell detection was established. In this biosensor system, stage-specific embryonic antigen-3 (SSEA-3) and stage-specific embryonic antigen-4 (SSEA-4) were used to mark human pluripotent stem cells (hPSCs). Antibody specific for SSEA-3 was coated onto magnetic beads for hPSCs enrichment, and antibody specific for SSEA-4 was conjugated with carboxyl-modified tDNA sequence which was used as template for strand displacement amplification (SDA). The amplified single strand DNA (ssDNA) was detected with a lateral flow biosensor (LFB). This biosensor is capable of detecting a minimum of 19 human embryonic stem cells by a strip reader and 100 human embryonic stem cells by the naked eye within 80min. This approach has also shown excellent specificity to distinguish hPSCs from other types of cells, showing that it is promising for specific and handy detection of human pluripotent stem cells. Copyright © 2015 Elsevier B.V. All rights reserved.

3 CFR 13505 - Executive Order 13505 of March 9, 2009. Removing Barriers to Responsible Scientific Research...

Code of Federal Regulations, 2010 CFR

2010-01-01

... Barriers to Responsible Scientific Research Involving Human Stem Cells 13505 Order 13505 Presidential... Scientific Research Involving Human Stem Cells By the authority vested in me as President by the Constitution.... Research involving human embryonic stem cells and human non-embryonic stem cells has the potential to lead...

Evaluation of a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay (SOT)

EPA Science Inventory

The Embryonic Stem Cell Test (EST) has been used to evaluate the effects of xenobiotics using three endpoints, stem cell differentiation, stem cell viability and 3T3-cell viability. Our research goal is to establish amodel system that would evaluate chemical effects using a singl...

Childhood Liver Cancer Treatment (PDQ®)—Health Professional Version

Cancer.gov

Childhood liver cancer has two major histologic subgroups: hepatoblastoma and hepatocellular carcinoma. Less common histologies are undifferentiated embryonal sarcoma of the liver, infantile choriocarcinoma, and vascular liver tumors. Get detailed information about newly diagnosed and recurrent childhood liver cancers including tumor biology, presentation, prognosis, staging, and treatment in this summary for clinicians.

Chemical Activation of the Hypoxia-Inducible Factor Reversibly Reduces Tendon Stem Cell Proliferation, Inhibits Their Differentiation, and Maintains Cell Undifferentiation.

PubMed

Menon, Alessandra; Creo, Pasquale; Piccoli, Marco; Bergante, Sonia; Conforti, Erika; Banfi, Giuseppe; Randelli, Pietro; Anastasia, Luigi

2018-01-01

Adult stem cell-based therapeutic approaches for tissue regeneration have been proposed for several years. However, adult stem cells are usually limited in number and difficult to be expanded in vitro, and they usually tend to quickly lose their potency with passages, as they differentiate and become senescent. Culturing stem cells under reduced oxygen tensions (below 21%) has been proposed as a tool to increase cell proliferation, but many studies reported opposite effects. In particular, cell response to hypoxia seems to be very stem cell type specific. Nonetheless, it is clear that a major role in this process is played by the hypoxia inducible factor (HIF), the master regulator of cell response to oxygen deprivation, which affects cell metabolism and differentiation. Herein, we report that a chemical activation of HIF in human tendon stem cells reduces their proliferation and inhibits their differentiation in a reversible and dose-dependent manner. These results support the notion that hypoxia, by activating HIF, plays a crucial role in preserving stem cells in an undifferentiated state in the "hypoxic niches" present in the tissue in which they reside before migrating in more oxygenated areas to heal a damaged tissue.

Evaluation of 309 environmental chemicals using a mouse embryonic stem cell adherent cell differentiation and cytotoxicity assay

EPA Science Inventory

The vast landscape of environmental chemicals has motivated the need for alternative methods to traditional whole-animal bioassays in toxicity testing. Embryonic stem (ES) cells provide an in vitro model of embryonic development and an alternative method for assessing development...

Functional characterization of cell hybrids generated by induced fusion of primary porcine mesenchymal stem cells with an immortal murine cell line.

PubMed

Islam, M Q; Ringe, J; Reichmann, E; Migotti, R; Sittinger, M; da S Meirelles, L; Nardi, N B; Magnusson, P; Islam, K

2006-10-01

Bone marrow mesenchymal stem cells (MSC) integrate into various organs and contribute to the regeneration of diverse tissues. However, the mechanistic basis of the plasticity of MSC is not fully understood. The change of cell fate has been suggested to occur through cell fusion. We have generated hybrid cell lines by polyethylene-glycol-mediated cell fusion of primary porcine MSC with the immortal murine fibroblast cell line F7, a derivative of the GM05267 cell line. The hybrid cell lines display fibroblastic morphology and proliferate like immortal cells. They contain tetraploid to hexaploid porcine chromosomes accompanied by hypo-diploid murine chromosomes. Interestingly, many hybrid cell lines also express high levels of tissue-nonspecific alkaline phosphatase, which is considered to be a marker of undifferentiated embryonic stem cells. All tested hybrid cell lines retain osteogenic differentiation, a few of them also retain adipogenic potential, but none retain chondrogenic differentiation. Conditioned media from hybrid cells enhance the proliferation of both early-passage and late-passage porcine MSC, indicating that the hybrid cells secrete diffusible growth stimulatory factors. Murine F7 cells thus have the unique property of generating immortal cell hybrids containing unusually high numbers of chromosomes derived from normal cells. These hybrid cells can be employed in various studies to improve our understanding of regenerative biology. This is the first report, to our knowledge, describing the generation of experimentally induced cell hybrids by using normal primary MSC.

Nuclear accumulation and activation of p53 in embryonic stem cells after DNA damage.

PubMed

Solozobova, Valeriya; Rolletschek, Alexandra; Blattner, Christine

2009-06-17

P53 is a key tumor suppressor protein. In response to DNA damage, p53 accumulates to high levels in differentiated cells and activates target genes that initiate cell cycle arrest and apoptosis. Since stem cells provide the proliferative cell pool within organisms, an efficient DNA damage response is crucial. In proliferating embryonic stem cells, p53 is localized predominantly in the cytoplasm. DNA damage-induced nuclear accumulation of p53 in embryonic stem cells activates transcription of the target genes mdm2, p21, puma and noxa. We observed bi-phasic kinetics for nuclear accumulation of p53 after ionizing radiation. During the first wave of nuclear accumulation, p53 levels were increased and the p53 target genes mdm2, p21 and puma were transcribed. Transcription of noxa correlated with the second wave of nuclear accumulation. Transcriptional activation of p53 target genes resulted in an increased amount of proteins with the exception of p21. While p21 transcripts were efficiently translated in 3T3 cells, we failed to see an increase in p21 protein levels after IR in embryonal stem cells. In embryonic stem cells where (anti-proliferative) p53 activity is not necessary, or even unfavorable, p53 is retained in the cytoplasm and prevented from activating its target genes. However, if its activity is beneficial or required, p53 is allowed to accumulate in the nucleus and activates its target genes, even in embryonic stem cells.

YAP/TAZ enhance mammalian embryonic neural stem cell characteristics in a Tead-dependent manner

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Dasol; Byun, Sung-Hyun; Park, Soojeong

Mammalian brain development is regulated by multiple signaling pathways controlling cell proliferation, migration and differentiation. Here we show that YAP/TAZ enhance embryonic neural stem cell characteristics in a cell autonomous fashion using diverse experimental approaches. Introduction of retroviral vectors expressing YAP or TAZ into the mouse embryonic brain induced cell localization in the ventricular zone (VZ), which is the embryonic neural stem cell niche. This change in cell distribution in the cortical layer is due to the increased stemness of infected cells; YAP-expressing cells were colabeled with Sox2, a neural stem cell marker, and YAP/TAZ increased the frequency and sizemore » of neurospheres, indicating enhanced self-renewal- and proliferative ability of neural stem cells. These effects appear to be TEA domain family transcription factor (Tead)–dependent; a Tead binding-defective YAP mutant lost the ability to promote neural stem cell characteristics. Consistently, in utero gene transfer of a constitutively active form of Tead2 (Tead2-VP16) recapitulated all the features of YAP/TAZ overexpression, and dominant negative Tead2-EnR resulted in marked cell exit from the VZ toward outer cortical layers. Taken together, these results indicate that the Tead-dependent YAP/TAZ signaling pathway plays important roles in neural stem cell maintenance by enhancing stemness of neural stem cells during mammalian brain development. - Highlights: • Roles of YAP and Tead in vivo during mammalian brain development are clarified. • Expression of YAP promotes embryonic neural stem cell characteristics in vivo in a cell autonomous fashion. • Enhancement of neural stem cell characteristics by YAP depends on Tead. • Transcriptionally active form of Tead alone can recapitulate the effects of YAP. • Transcriptionally repressive form of Tead severely reduces stem cell characteristics.« less

Human Embryonic Stem Cell Therapy in Crohn's Disease: A Case Report.

PubMed

Shroff, Geeta

2016-02-29

Crohn's disease is a chronic inflammatory disease of the intestines, mainly the colon and ileum, related with ulcers and fistulae. It is estimated to affect 565,000 people in the United States. Currently available therapies, such as antibiotics, thiopurines, and anti-tumor necrosis factor-alpha agents, are only observed to reduce the complications associated with Crohn's disease and to improve quality of life, but cannot cure the disease. Stem cell therapy appears to have certain advantages over conventional therapies. Our study aimed to evaluate the efficacy of human embryonic stem cell therapy in a patient with Crohn's disease. A 21-year-old male with chief complaints of intolerance to specific foods, abdominal pain, and diarrhea underwent human embryonic stem cell therapy for two months. After undergoing human embryonic stem cell therapy, the patient showed symptomatic relief. He had no complaints of back pain, abdominal pain, or diarrhea and had improved digestion. The patient had no signs and symptoms of skin infection, and had improved limb stamina, strength, and endurance. The condition of patient was stable after the therapy. Human embryonic stem cell therapy might serve as a new optimistic treatment approach for Crohn's disease.

Bio-engineering inslulin-secreting cells from embryonic stem cells: a review of progress.

PubMed

Roche, E; Sepulcre, M P; Enseñat-Waser, R; Maestre, I; Reig, J A; Soria, B

2003-07-01

According to the Edmonton protocol, human islet transplantation can result in insulin independency for periods longer than 3 years. However, this therapy for type 1 diabetes is limited by the scarcity of cadaveric donors. Owing to the ability of embryonic stem cells to expand in vitro and differentiate into a variety of cell types, research has focused on ways to manipulate these cells to overcome this problem. It has been demonstrated that mouse embryonic stem cells can differentiate into insulin-containing cells, restoring normoglycaemia in diabetic mice. To this end, mouse embryonic stem cells were transfected with a DNA construct that provides resistance to neomycin under the control of the regulatory regions of the human insulin gene. However, this protocol has a very low efficiency, needing improvements for this technology to be transferred to human stem cells. Optimum protocols will be instrumental in the production of an unlimited source of cells that synthesise, store and release insulin in a physiological manner. The review focuses on the alternative source of tissue offered by embryonic stem cells for regenerative medicine in diabetes and some key points that should be considered in order for a definitive protocol for in vitro differentiation to be established.

Defining an optimal surface chemistry for pluripotent stem cell culture in 2D and 3D

NASA Astrophysics Data System (ADS)

Zonca, Michael R., Jr.

Surface chemistry is critical for growing pluripotent stem cells in an undifferentiated state. There is great potential to engineer the surface chemistry at the nanoscale level to regulate stem cell adhesion. However, the challenge is to identify the optimal surface chemistry of the substrata for ES cell attachment and maintenance. Using a high-throughput polymerization and screening platform, a chemically defined, synthetic polymer grafted coating that supports strong attachment and high expansion capacity of pluripotent stem cells has been discovered using mouse embryonic stem (ES) cells as a model system. This optimal substrate, N-[3-(Dimethylamino)propyl] methacrylamide (DMAPMA) that is grafted on 2D synthetic poly(ether sulfone) (PES) membrane, sustains the self-renewal of ES cells (up to 7 passages). DMAPMA supports cell attachment of ES cells through integrin beta1 in a RGD-independent manner and is similar to another recently reported polymer surface. Next, DMAPMA has been able to be transferred to 3D by grafting to synthetic, polymeric, PES fibrous matrices through both photo-induced and plasma-induced polymerization. These 3D modified fibers exhibited higher cell proliferation and greater expression of pluripotency markers of mouse ES cells than 2D PES membranes. Our results indicated that desirable surfaces in 2D can be scaled to 3D and that both surface chemistry and structural dimension strongly influence the growth and differentiation of pluripotent stem cells. Lastly, the feasibility of incorporating DMAPMA into a widely used natural polymer, alginate, has been tested. Novel adhesive alginate hydrogels have been successfully synthesized by either direct polymerization of DMAPMA and methacrylic acid blended with alginate, or photo-induced DMAPMA polymerization on alginate nanofibrous hydrogels. In particular, DMAPMA-coated alginate hydrogels support strong ES cell attachment, exhibiting a concentration dependency of DMAPMA. This research provides a new avenue for stem cell culture and maintenance using an optimal organic-based chemistry.

A Model of Cancer Stem Cells Derived from Mouse Induced Pluripotent Stem Cells

PubMed Central

Chen, Ling; Kasai, Tomonari; Li, Yueguang; Sugii, Yuh; Jin, Guoliang; Okada, Masashi; Vaidyanath, Arun; Mizutani, Akifumi; Satoh, Ayano; Kudoh, Takayuki; Hendrix, Mary J. C.; Salomon, David S.; Fu, Li; Seno, Masaharu

2012-01-01

Cancer stem cells (CSCs) are capable of continuous proliferation and self-renewal and are proposed to play significant roles in oncogenesis, tumor growth, metastasis and cancer recurrence. CSCs are considered derived from normal stem cells affected by the tumor microenvironment although the mechanism of development is not clear yet. In 2007, Yamanaka's group succeeded in generating Nanog mouse induced pluripotent stem (miPS) cells, in which green fluorescent protein (GFP) has been inserted into the 5′-untranslated region of the Nanog gene. Usually, iPS cells, just like embryonic stem cells, are considered to be induced into progenitor cells, which differentiate into various normal phenotypes depending on the normal niche. We hypothesized that CSCs could be derived from Nanog miPS cells in the conditioned culture medium of cancer cell lines, which is a mimic of carcinoma microenvironment. As a result, the Nanog miPS cells treated with the conditioned medium of mouse Lewis lung carcinoma acquired characteristics of CSCs, in that they formed spheroids expressing GFP in suspension culture, and had a high tumorigenicity in Balb/c nude mice exhibiting angiogenesis in vivo. In addition, these iPS-derived CSCs had a capacity of self-renewal and expressed the marker genes, Nanog, Rex1, Eras, Esg1 and Cripto, associated with stem cell properties and an undifferentiated state. Thus we concluded that a model of CSCs was originally developed from miPS cells and proposed the conditioned culture medium of cancer cell lines might perform as niche for producing CSCs. The model of CSCs and the procedure of their establishment will help study the genetic alterations and the secreted factors in the tumor microenvironment which convert miPS cells to CSCs. Furthermore, the identification of potentially bona fide markers of CSCs, which will help the development of novel anti-cancer therapies, might be possible though the CSC model. PMID:22511923

Stem cell maintenance by manipulating signaling pathways: past, current and future

PubMed Central

Chen, Xi; Ye, Shoudong; Ying, Qi-Long

2015-01-01

Pluripotent stem cells only exist in a narrow window during early embryonic development, whereas multipotent stem cells are abundant throughout embryonic development and are retainedin various adult tissues and organs. While pluripotent stem cell lines have been established from several species, including mouse, rat, and human, it is still challenging to establish stable multipotent stem cell lines from embryonic or adult tissues. Based on current knowledge, we anticipate that by manipulating extrinsic and intrinsic signaling pathways, most if not all types of stem cells can be maintained in a long-term culture. In this article, we summarize current culture conditions established for the long-term maintenance of authentic pluripotent and multipotent stem cells and the signaling pathways involved. We also discuss the general principles of stem cell maintenance and propose several strategies on the establishment of novel stem cell lines through manipulation of signaling pathways. [BMB Reports 2015; 48(12): 668-676] PMID:26497581

Investigation for the differentiation process of mouse ES cells by Raman spectroscopy

NASA Astrophysics Data System (ADS)

Yamaguchi, Yoshinori; El-Hagrasy, Maha A.; Shimizu, Eiichi; Saito, Masato; Tamiya, Eiichi

2012-03-01

The arrangement of differentiated pluripotent embryonic stem cells into three-dimensional aggregates, which are known as embryonic bodies, is a main step for progressing the embryonic stem cells differentiation. In this work, embryonic stem cells that were directly produced from the hanging drop step as a three-dimensional structure with no further twodimensional differentiation were diagnosed with Raman spectroscopy as a non-invasive and label-free technique. Raman spectroscopy was employed to discriminate between mouse embryonic bodies of different degrees of maturation. EBs were prepared applying the hanging drop method. The Raman scattering measurements were obtained in vitro with a Nanophoton RAMAN-11 micro-spectrometer (Japan: URL: www.nanophoton.jp equipped with an Olympus XLUM Plan FLN 20X/NA= 1.0 objective lens. Spectral data were smoothed, baseline corrected and normalized to the a welldefined intense 1003 cm-1 band (phenylalanine) which is insensitive to changes in conformation or environment. The differentiation process of embryonic stem cells is initiated by the removal of LIF from culture medium. 1, 7 and 17-dayold embryonic stem cells were collected and investigated by Raman spectroscopy. The main differences involve bands which decreased with maturation such as: 784 cm-1 (U, T, C ring br DNA/RNA, O-P-O str); 1177 cm-1 (cytosine, guanine) and 1578 cm-1 (G, A). It was found that with the progress of differentiation the protein content was amplified. The increase of protein to nucleic acid ratio was also previously observed with the progress of the differentiation process. Raman spectroscopy has the potential to distinguish between the Raman signatures of live embryonic stem cells with different degrees of maturation.

Spermatogonial Stem Cell Niche and Spermatogonial Stem Cell Transplantation in Zebrafish

PubMed Central

Nóbrega, Rafael Henrique; Greebe, Caaj Douwe; van de Kant, Henk; Bogerd, Jan; de França, Luiz Renato; Schulz, Rüdiger W.

2010-01-01

Background Spermatogonial stem cells (SSCs) are the foundation of spermatogenesis, and reside within a specific microenvironment in the testes called “niche” which regulates stem cell properties, such as, self-renewal, pluripotency, quiescence and their ability to differentiate. Methodology/Principal Findings Here, we introduce zebrafish as a new model for the study of SSCs in vertebrates. Using 5′-bromo-2′-deoxyuridine (BrdU), we identified long term BrdU-retaining germ cells, type A undifferentiated spermatogonia as putative stem cells in zebrafish testes. Similar to rodents, these cells were preferentially located near the interstitium, suggesting that the SSC niche is related to interstitial elements and might be conserved across vertebrates. This localization was also confirmed by analyzing the topographical distribution of type A undifferentiated spermatogonia in normal, vasa::egfp and fli::egfp zebrafish testes. In the latter one, the topographical arrangement suggested that the vasculature is important for the SSC niche, perhaps as a supplier of nutrients, oxygen and/or signaling molecules. We also developed an SSC transplantation technique for both male and female recipients as an assay to evaluate the presence, biological activity, and plasticity of the SSC candidates in zebrafish. Conclusions/Significance We demonstrated donor-derived spermato- and oogenesis in male and female recipients, respectively, indicating the stemness of type A undifferentiated spermatogonia and their plasticity when placed into an environment different from their original niche. Similar to other vertebrates, the transplantation efficiency was low. This might be attributed to the testicular microenvironment created after busulfan depletion in the recipients, which may have caused an imbalance between factors regulating self-renewal or differentiation of the transplanted SSCs. PMID:20862221

Assembly of embryonic and extraembryonic stem cells to mimic embryogenesis in vitro.

PubMed

Harrison, Sarah Ellys; Sozen, Berna; Christodoulou, Neophytos; Kyprianou, Christos; Zernicka-Goetz, Magdalena

2017-04-14

Mammalian embryogenesis requires intricate interactions between embryonic and extraembryonic tissues to orchestrate and coordinate morphogenesis with changes in developmental potential. Here, we combined mouse embryonic stem cells (ESCs) and extraembryonic trophoblast stem cells (TSCs) in a three-dimensional scaffold to generate structures whose morphogenesis is markedly similar to that of natural embryos. By using genetically modified stem cells and specific inhibitors, we show that embryogenesis of ESC- and TSC-derived embryos-ETS-embryos-depends on cross-talk involving Nodal signaling. When ETS-embryos develop, they spontaneously initiate expression of mesoderm and primordial germ cell markers asymmetrically on the embryonic and extraembryonic border, in response to Wnt and BMP signaling. Our study demonstrates the ability of distinct stem cell types to self-assemble in vitro to generate embryos whose morphogenesis, architecture, and constituent cell types resemble those of natural embryos. Copyright © 2017, American Association for the Advancement of Science.

Blastocyst-like structures generated solely from stem cells.

PubMed

Rivron, Nicolas C; Frias-Aldeguer, Javier; Vrij, Erik J; Boisset, Jean-Charles; Korving, Jeroen; Vivié, Judith; Truckenmüller, Roman K; van Oudenaarden, Alexander; van Blitterswijk, Clemens A; Geijsen, Niels

2018-05-01

The blastocyst (the early mammalian embryo) forms all embryonic and extra-embryonic tissues, including the placenta. It consists of a spherical thin-walled layer, known as the trophectoderm, that surrounds a fluid-filled cavity sheltering the embryonic cells 1 . From mouse blastocysts, it is possible to derive both trophoblast 2 and embryonic stem-cell lines 3 , which are in vitro analogues of the trophectoderm and embryonic compartments, respectively. Here we report that trophoblast and embryonic stem cells cooperate in vitro to form structures that morphologically and transcriptionally resemble embryonic day 3.5 blastocysts, termed blastoids. Like blastocysts, blastoids form from inductive signals that originate from the inner embryonic cells and drive the development of the outer trophectoderm. The nature and function of these signals have been largely unexplored. Genetically and physically uncoupling the embryonic and trophectoderm compartments, along with single-cell transcriptomics, reveals the extensive inventory of embryonic inductions. We specifically show that the embryonic cells maintain trophoblast proliferation and self-renewal, while fine-tuning trophoblast epithelial morphogenesis in part via a BMP4/Nodal-KLF6 axis. Although blastoids do not support the development of bona fide embryos, we demonstrate that embryonic inductions are crucial to form a trophectoderm state that robustly implants and triggers decidualization in utero. Thus, at this stage, the nascent embryo fuels trophectoderm development and implantation.

Structural Complexity of Non-acid Glycosphingolipids in Human Embryonic Stem Cells Grown under Feeder-free Conditions*

PubMed Central

Barone, Angela; Benktander, John; Ångström, Jonas; Aspegren, Anders; Björquist, Petter; Teneberg, Susann; Breimer, Michael. E.

2013-01-01

Due to their pluripotency and growth capability, there are great expectations for human embryonic stem cells, both as a resource for functional studies of early human development and as a renewable source of cells for use in regenerative medicine and transplantation. However, to bring human embryonic stem cells into clinical applications, their cell surface antigen expression and its chemical structural complexity have to be defined. In the present study, total non-acid glycosphingolipid fractions were isolated from two human embryonic stem cell lines (SA121 and SA181) originating from leftover in vitro fertilized human embryos, using large amounts of starting material (1 × 109 cells/cell line). The total non-acid glycosphingolipid fractions were characterized by antibody and lectin binding, mass spectrometry, and proton NMR. In addition to the globo-series and type 1 core chain glycosphingolipids previously described in human embryonic stem cells, a number of type 2 core chain glycosphingolipids (neo-lactotetraosylceramide, the H type 2 pentaosylceramide, the Lex pentaosylceramide, and the Ley hexaosylceramide) were identified as well as the blood group A type 1 hexaosylceramide. Finally, the mono-, di-, and triglycosylceramides were characterized as galactosylceramide, glucosylceramide, lactosylceramide, galabiaosylceramide, globotriaosylceramide, and lactotriaosylceramide. Thus, the glycan diversity of human embryonic stem cells, including cell surface immune determinants, is more complex than previously appreciated. PMID:23404501

Differentiation and Transplantation of Human Embryonic Stem Cell-Derived Hepatocytes

PubMed Central

Basma, Hesham; Soto-Gutiérrez, Alejandro; Yannam, Govardhana Rao; Liu, Liping; Ito, Ryotaro; Yamamoto, Toshiyuki; Ellis, Ewa; Carson, Steven D.; Sato, Shintaro; Chen, Yong; Muirhead, David; Navarro-Álvarez, Nalu; Wong, Ron; Roy-Chowdhury, Jayanta; Platt, Jeffrey L.; Mercer, David F.; Miller, John D.; Strom, Stephen C.; Kobayashi, Noaya; Fox, Ira J.

2009-01-01

Background & Aims The ability to obtain unlimited numbers of human hepatocytes would improve development of cell-based therapies for liver diseases, facilitate the study of liver biology and improve the early stages of drug discovery. Embryonic stem cells are pluripotent, can potentially differentiate into any cell type and could therefore be developed as a source of human hepatocytes. Methods To generate human hepatocytes, human embryonic stem cells were differentiated by sequential culture in fibroblast growth factor 2 and human Activin-A, hepatocyte growth factor, and dexamethasone. Functional hepatocytes were isolated by sorting for surface asialoglycoprotein receptor expression. Characterization was performed by real-time PCR, imunohistochemistry, immunoblot, functional assays and transplantation. Results Embryonic stem cell-derived hepatocytes expressed liver-specific genes but not genes representing other lineages, secreted functional human liver-specific proteins similar to those of primary human hepatocytes and demonstrated human hepatocyte cytochrome P450 metabolic activity. Serum from rodents given injections of embryonic stem cell-derived hepatocytes contained significant amounts of human albumin and alpha-1-antitrypsin. Colonies of cytokeratin-18 and human albumin-expressing cells were present in the livers of recipient animals. Conclusion Human embryonic stem cells can be differentiated into cells with many characteristics of primary human hepatocytes. Hepatocyte-like cells can be enriched and recovered based on asialoglycoprotein receptor expression and could potentially be used in drug discovery research and developed as therapeutics. PMID:19026649

Application of Stem Cells in Oral Disease Therapy: Progresses and Perspectives

PubMed Central

Yang, Bo; Qiu, Yi; Zhou, Niu; Ouyang, Hong; Ding, Junjun; Cheng, Bin; Sun, Jianbo

2017-01-01

Stem cells are undifferentiated and pluripotent cells that can differentiate into specialized cells with a more specific function. Stem cell therapies become preferred methods for the treatment of multiple diseases. Oral and maxillofacial defect is one kind of the diseases that could be most possibly cured by stem cell therapies. Here we discussed oral diseases, oral adult stem cells, iPS cells, and the progresses/challenges/perspectives of application of stem cells for oral disease treatment. PMID:28421002

Embryonic attenuated Wnt/β-catenin signaling defines niche location and long-term stem cell fate in hair follicle

PubMed Central

Xu, Zijian; Wang, Wenjie; Jiang, Kaiju; Yu, Zhou; Huang, Huanwei; Wang, Fengchao; Zhou, Bin; Chen, Ting

2015-01-01

Long-term adult stem cells sustain tissue regeneration throughout the lifetime of an organism. They were hypothesized to originate from embryonic progenitor cells that acquire long-term self-renewal ability and multipotency at the end of organogenesis. The process through which this is achieved often remains unclear. Here, we discovered that long-term hair follicle stem cells arise from embryonic progenitor cells occupying a niche location that is defined by attenuated Wnt/β-catenin signaling. Hair follicle initiation is marked by placode formation, which depends on the activation of Wnt/β-catenin signaling. Soon afterwards, a region with attenuated Wnt/β-catenin signaling emerges in the upper follicle. Embryonic progenitor cells residing in this region gain expression of adult stem cell markers and become definitive long-term hair follicle stem cells at the end of organogenesis. Attenuation of Wnt/β-catenin signaling is a prerequisite for hair follicle stem cell specification because it suppresses Sox9, which is required for stem cell formation. DOI: http://dx.doi.org/10.7554/eLife.10567.001 PMID:26653852

[Cell therapy for Parkinson's disease: IV. Risks and future trends].

PubMed

Anisimov, S V

2009-01-01

Motor dysfunctions in Parkinson's disease are believed to be primarily due to the degeneration of dopaminergic neurons located in the substantia nigra pars compacta. Numerous cell replacement therapy approaches have been developed and tested, including these based on donor cell transplantation (embryonic and adult tissue-derived), adult mesenchymal stem cells (hMSCs)-, neural stem cells (hNSCs)- and finally human embryonic stem cells (hESCs)-based. Despite the progress achieved, numerous difficulties prevent wider practical application of stem cell-based therapy approaches for the treatment of Parkinson's disease. Among the latter, ethical, safety and technical issues stand out. Current series of reviews (Cell therapy for Parkinson's disease: I. Embryonic and adult donor tissue-based applications; II. Adult stem cell-based applications; III. Neonatal, fetal and embryonic stem cell-based applications; IV. Risks and future trends) aims providing a balanced and updated view on various issues associated with cell types (including stem cells) in regards to their potential in the treatment of Parkinson's disease. Essential features of the individual cell subtypes, principles of available cell handling protocols, transplantation, and safety issues are discussed extensively.

The ethics of patenting human embryonic stem cells.

PubMed

Chapman, Audrey R

2009-09-01

Just as human embryonic stem cell research has generated controversy about the uses of human embryos for research and therapeutic applications, human embryonic stem cell patents raise fundamental ethical issues. The United States Patent and Trademark Office has granted foundational patents, including a composition of matter (or product) patent to the Wisconsin Alumni Research Foundation (WARF), the University of Wisconsin-Madison's intellectual property office. In contrast, the European Patent Office rejected the same WARF patent application for ethical reasons. This article assesses the appropriateness of these patents placing the discussion in the context of the deontological and consequentialist ethical issues related to human embryonic stem cell patenting. It advocates for a patent system that explicitly takes ethical factors into account and explores options for new types of intellectual property arrangements consistent with ethical concerns.

Cryopreservation of Human Stem Cells for Clinical Application: A Review

PubMed Central

Hunt, Charles J.

2011-01-01

Summary Stem cells have been used in a clinical setting for many years. Haematopoietic stem cells have been used for the treatment of both haematological and non-haematological disease; while more recently mesenchymal stem cells derived from bone marrow have been the subject of both laboratory and early clinical studies. Whilst these cells show both multipotency and expansion potential, they nonetheless do not form stable cell lines in culture which is likely to limit the breadth of their application in the field of regenerative medicine. Human embryonic stem cells are pluripotent cells, capable of forming stable cell lines which retain the capacity to differentiate into cells from all three germ layers. This makes them of special significance in both regenerative medicine and toxicology. Induced pluripotent stem (iPS) cells may also provide a similar breadth of utility without some of the confounding ethical issues surrounding embryonic stem cells. An essential pre-requisite to the commercial and clinical application of stem cells are suitable cryopreservation protocols for long-term storage. Whilst effective methods for cryopreservation and storage have been developed for haematopoietic and mesenchymal stem cells, embryonic cells and iPS cells have proved more refractory. This paper reviews the current state of cryopreservation as it pertains to stem cells and in particular the embryonic and iPS cell. PMID:21566712

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

PubMed

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

2016-01-01

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

Cryopreservation of Human Stem Cells for Clinical Application: A Review.

PubMed

Hunt, Charles J

2011-01-01

SUMMARY: Stem cells have been used in a clinical setting for many years. Haematopoietic stem cells have been used for the treatment of both haematological and non-haematological disease; while more recently mesenchymal stem cells derived from bone marrow have been the subject of both laboratory and early clinical studies. Whilst these cells show both multipotency and expansion potential, they nonetheless do not form stable cell lines in culture which is likely to limit the breadth of their application in the field of regenerative medicine. Human embryonic stem cells are pluripotent cells, capable of forming stable cell lines which retain the capacity to differentiate into cells from all three germ layers. This makes them of special significance in both regenerative medicine and toxicology. Induced pluripotent stem (iPS) cells may also provide a similar breadth of utility without some of the confounding ethical issues surrounding embryonic stem cells. An essential pre-requisite to the commercial and clinical application of stem cells are suitable cryopreservation protocols for long-term storage. Whilst effective methods for cryopreservation and storage have been developed for haematopoietic and mesenchymal stem cells, embryonic cells and iPS cells have proved more refractory. This paper reviews the current state of cryopreservation as it pertains to stem cells and in particular the embryonic and iPS cell.

Modeling TSC and LAM Using Patient Derived Induced Pluripotent Stem Cells

DTIC Science & Technology

2016-10-01

lentiviral knockdown, and CRISPR /Cas9 genome editing in embryonic stem cells (ESCs). We have characterized the iPSCs extensively and found that they display...induced pluripotent stem cells (iPSCs) embryonic stem cells (ESCs) reprogramming CRISPR /Cas9 genome editing neural stem cells (NSCs) neural crest... CRISPR /cas9 in two additional human pluripotent stem cell lines (WA07 (H7) – female cell line registry #0061; and a control male iPSC lines generated

gone early, a Novel Germline Factor, Ensures the Proper Size of the Stem Cell Precursor Pool in the Drosophila Ovary

PubMed Central

Matsuoka, Shinya; Gupta, Swati; Suzuki, Emiko; Hiromi, Yasushi; Asaoka, Miho

2014-01-01

In order to sustain lifelong production of gametes, many animals have evolved a stem cell–based gametogenic program. In the Drosophila ovary, germline stem cells (GSCs) arise from a pool of primordial germ cells (PGCs) that remain undifferentiated even after gametogenesis has initiated. The decision of PGCs to differentiate or remain undifferentiated is regulated by somatic stromal cells: specifically, epidermal growth factor receptor (EGFR) signaling activated in the stromal cells determines the fraction of germ cells that remain undifferentiated by shaping a Decapentaplegic (Dpp) gradient that represses PGC differentiation. However, little is known about the contribution of germ cells to this process. Here we show that a novel germline factor, Gone early (Goe), limits the fraction of PGCs that initiate gametogenesis. goe encodes a non-peptidase homologue of the Neprilysin family metalloendopeptidases. At the onset of gametogenesis, Goe was localized on the germ cell membrane in the ovary, suggesting that it functions in a peptidase-independent manner in cell–cell communication at the cell surface. Overexpression of Goe in the germline decreased the number of PGCs that enter the gametogenic pathway, thereby increasing the proportion of undifferentiated PGCs. Inversely, depletion of Goe increased the number of PGCs initiating differentiation. Excess PGC differentiation in the goe mutant was augmented by halving the dose of argos, a somatically expressed inhibitor of EGFR signaling. This increase in PGC differentiation resulted in a massive decrease in the number of undifferentiated PGCs, and ultimately led to insufficient formation of GSCs. Thus, acting cooperatively with a somatic regulator of EGFR signaling, the germline factor goe plays a critical role in securing the proper size of the GSC precursor pool. Because goe can suppress EGFR signaling activity and is expressed in EGF-producing cells in various tissues, goe may function by attenuating EGFR signaling, and thereby affecting the stromal environment. PMID:25420147

[Ethical aspects of human embryonic stem cell use and commercial umbilical cord blood stem cell banking. Ethical reflections on the occasion of the regulation of the European Council and Parliament on advanced therapy medicinal products].

PubMed

Virt, G

2010-01-01

The regulation of the European Council and Parliament on advanced therapy medicinal products also includes therapies with human embryonic stem cells. The use of these stem cells is controversially and heavily discussed. Contrary to the use of adult stem cells, medical and ethical problems concerning the use of human embryonic stem cells persists, because this use is based on the destruction of human life at the very beginning. The regulation foresees, therefore, subsidiarity within the European Member States. Although there are no ethical problems in principle with the use of stem cells from the umbilical cord blood, there are social ethical doubts with the banking of these stem cells for autologous use without any currently foreseeable medical advantage by commercial blood banks. Also in this case subsidiarity is valid.

Novel Method To Differentiate Human Embryonic Stem Cells Into Dopaminergic Nerve Cells | NCI Technology Transfer Center | TTC

Cancer.gov

The National Institute on Drug Abuse's Development and Plasticity Section is seeking statements of capability or interest from parties interested in licensing opportunities to further develop, evaluate, or commercialize novel methods to differentiate human embryonic stem cells into dopaminergic nerve cells. The invention described here is a novel method of differentiating human embryonic stem cells (hESCs) into dopaminergic nerve cells, which is preferable to the currently available dopaminergic differentiation techniques.

mTORC1 is essential for leukemia propagation but not stem cell self-renewal

PubMed Central

Hoshii, Takayuki; Tadokoro, Yuko; Naka, Kazuhito; Ooshio, Takako; Muraguchi, Teruyuki; Sugiyama, Naoyuki; Soga, Tomoyoshi; Araki, Kimi; Yamamura, Ken-ichi; Hirao, Atsushi

2012-01-01

Although dysregulation of mTOR complex 1 (mTORC1) promotes leukemogenesis, how mTORC1 affects established leukemia is unclear. We investigated the role of mTORC1 in mouse hematopoiesis using a mouse model of conditional deletion of Raptor, an essential component of mTORC1. Raptor deficiency impaired granulocyte and B cell development but did not alter survival or proliferation of hematopoietic progenitor cells. In a mouse model of acute myeloid leukemia (AML), Raptor deficiency significantly suppressed leukemia progression by causing apoptosis of differentiated, but not undifferentiated, leukemia cells. mTORC1 did not control cell cycle or cell growth in undifferentiated AML cells in vivo. Transplantation of Raptor-deficient undifferentiated AML cells in a limiting dilution revealed that mTORC1 is essential for leukemia initiation. Strikingly, a subset of AML cells with undifferentiated phenotypes survived long-term in the absence of mTORC1 activity. We further demonstrated that the reactivation of mTORC1 in those cells restored their leukemia-initiating capacity. Thus, AML cells lacking mTORC1 activity can self-renew as AML stem cells. Our findings provide mechanistic insight into how residual tumor cells circumvent anticancer therapies and drive tumor recurrence. PMID:22622041

Are You Teaching Your Students about Stem Cells?

ERIC Educational Resources Information Center

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…

Mitochondrial functionality in reproduction: from gonads and gametes to embryos and embryonic stem cells.

PubMed

Ramalho-Santos, João; Varum, Sandra; Amaral, Sandra; Mota, Paula C; Sousa, Ana Paula; Amaral, Alexandra

2009-01-01

Mitochondria are multitasking organelles involved in ATP synthesis, reactive oxygen species (ROS) production, calcium signalling and apoptosis; and mitochondrial defects are known to cause physiological dysfunction, including infertility. The goal of this review was to identify and discuss common themes in mitochondrial function related to mammalian reproduction. The scientific literature was searched for studies reporting on the several aspects of mitochondrial activity in mammalian testis, sperm, oocytes, early embryos and embryonic stem cells. ATP synthesis and ROS production are the most discussed aspects of mitochondrial function. Metabolic shifts from mitochondria-produced ATP to glycolysis occur at several stages, notably during gametogenesis and early embryo development, either reflecting developmental switches or substrate availability. The exact role of sperm mitochondria is especially controversial. Mitochondria-generated ROS function in signalling but are mostly described when produced under pathological conditions. Mitochondria-based calcium signalling is primarily important in embryo activation and embryonic stem cell differentiation. Besides pathologically triggered apoptosis, mitochondria participate in apoptotic events related to the regulation of spermatogonial cell number, as well as gamete, embryo and embryonic stem cell quality. Interestingly, data from knock-out (KO) mice is not always straightforward in terms of expected phenotypes. Finally, recent data suggests that mitochondrial activity can modulate embryonic stem cell pluripotency as well as differentiation into distinct cellular fates. Mitochondria-based events regulate different aspects of reproductive function, but these are not uniform throughout the several systems reviewed. Low mitochondrial activity seems a feature of 'stemness', being described in spermatogonia, early embryo, inner cell mass cells and embryonic stem cells.

Method for evaluation of human induced pluripotent stem cell quality using image analysis based on the biological morphology of cells.

PubMed

Wakui, Takashi; Matsumoto, Tsuyoshi; Matsubara, Kenta; Kawasaki, Tomoyuki; Yamaguchi, Hiroshi; Akutsu, Hidenori

2017-10-01

We propose an image analysis method for quality evaluation of human pluripotent stem cells based on biologically interpretable features. It is important to maintain the undifferentiated state of induced pluripotent stem cells (iPSCs) while culturing the cells during propagation. Cell culture experts visually select good quality cells exhibiting the morphological features characteristic of undifferentiated cells. Experts have empirically determined that these features comprise prominent and abundant nucleoli, less intercellular spacing, and fewer differentiating cellular nuclei. We quantified these features based on experts' visual inspection of phase contrast images of iPSCs and found that these features are effective for evaluating iPSC quality. We then developed an iPSC quality evaluation method using an image analysis technique. The method allowed accurate classification, equivalent to visual inspection by experts, of three iPSC cell lines.

Embryonic stem cells and prospects for their use in regenerative medicine approaches to motor neurone disease.

PubMed

Christou, Y A; Moore, H D; Shaw, P J; Monk, P N

2007-10-01

Human embryonic stem cells are pluripotent cells with the potential to differentiate into any cell type in the presence of appropriate stimulatory factors and environmental cues. Their broad developmental potential has led to valuable insights into the principles of developmental and cell biology and to the proposed use of human embryonic stem cells or their differentiated progeny in regenerative medicine. This review focuses on the prospects for the use of embryonic stem cells in cell-based therapy for motor neurone disease or amyotrophic lateral sclerosis, a progressive neurodegenerative disease that specifically affects upper and lower motor neurones and leads ultimately to death from respiratory failure. Stem cell-derived motor neurones could conceivably be used to replace the degenerated cells, to provide authentic substrates for drug development and screening and for furthering our understanding of disease mechanisms. However, to reliably and accurately culture motor neurones, the complex pathways by which differentiation occurs in vivo must be understood and reiterated in vitro by embryonic stem cells. Here we discuss the need for new therapeutic strategies in the treatment of motor neurone disease, the developmental processes that result in motor neurone formation in vivo, a number of experimental approaches to motor neurone production in vitro and recent progress in the application of stem cells to the treatment and understanding of motor neurone disease.

Comparative Chondrogenesis of Human Cell Sources in 3D Scaffolds

PubMed Central

Tıg̑lı, R. Seda; Ghosh, Sourabh; Laha, Michael M.; Shevde, Nirupama K.; Daheron, Laurence; Gimble, Jeffrey; Gümüşdereliog̑lu, Menemşe; Kaplan, David L.

2009-01-01

Cartilage tissue can be engineered by starting from a diversity of cell sources, including stem-cell based and primary cell-based platforms. Selecting an appropriate cell source for the process of cartilage tissue engineering or repair is critical and challenging due to the variety of cell options available. In this study, cellular responses of isolated human chondrocytes, human embryonic stem cells and mesenchymal stem cells (MSCs) derived from three sources, human embryonic stem cells, bone marrow and adipose tissue, were assessed for chondrogenic potential in 3D culture. All cell sources were characterized by FACS analysis to compare expression of some surface markers. The cells were differentiated in two different biomaterial matrices, silk and chitosan scaffolds, in the presence and absence of bone morphogenetic protein 6 (BMP-6) along with the standard chondrogenic differentiating factors. Embryonic stem cells derived MSCs showed unique characteristics with preserved chondrogenic phenotype in both scaffolds with regard to chondrogenesis, as determined by real time RT-PCR, histological and microscopic analyses. After 4 weeks of cultivation, embryonic stem cells derived MSCs were promising for chondrogenesis, particularly in the silk scaffolds with BMP-6. The results suggest that cell source differences are important to consider with regard to chondrogenic outcomes and with the variables addressed here, the human embryonic stem cells derived MSCs were the preferred cell source. PMID:19382119

Undifferentiated embryonic cell transcription factor 1 (UTF1) and deleted in azoospermia-like (DAZL) expression in the testes of donkeys.

PubMed

Lee, Y S; Jung, H J; Yoon, M J

2017-04-01

Putative markers for each specific germ cell stage can be a useful tool to study the fate and functions of these cells. Undifferentiated embryonic cell transcription factor 1 (UTF1) is a putative marker for undifferentiated spermatogonia in humans, rats and horses. The deleted in azoospermia-like (DAZL) protein is also expressed by differentiated spermatogonia and primary spermatocytes in several species. However, whether the expression patterns of these molecular markers are identical and applicable to donkeys remains to be elucidated. The objective of this study was to investigate the expression patterns of UTF1 and DAZL in donkey testicular tissue, using immunohistochemistry (IHC). Testicular samples were collected from routine field castration of donkeys in Korea. The reproductive stages (pre- or post-puberty) of the testes were determined from the morphological characteristics of cross-sections of the seminiferous tubules. For IHC, the UTF1 and DAZL primary antibodies were diluted at 1:100 and 1:200, respectively. The immunolabelling revealed that UTF1 was expressed in approximately 50% of spermatogonia in the pre-pubertal stage, whereas its expression was limited to an early subset of spermatogonia in the post-pubertal stage. DAZL was expressed in some, but not all, spermatogonia in the pre-pubertal spermatogonia, and interestingly, its expression was also observed in spermatogonia and primary spermatocytes in the post-pubertal stage. Co-immunolabelling of the germ cells with both UTF1 and DAZL revealed three types of protein expression patterns at both reproductive stages, namely UTF1 only, DAZL only and both UTF1 and DAZL. These protein molecules were not expressed in Sertoli and Leydig cells. In conclusion, a co-immunolabelling system with UTF1 and DAZL antibodies may be used to identify undifferentiated (UTF1 only), differentiating (UTF1 and DAZL), and differentiated spermatogonia (DAZL only) in donkey testes. © 2017 Blackwell Verlag GmbH.

Ethics and policy in embryonic stem cell research.

PubMed

Robertson, John A

1999-06-01

Embryonic stem cells, which have the potential to save many lives, must be recovered from aborted fetuses or live embyros. Although tissue from aborted fetuses can be used without moral complicity in the underlying abortion, obtaining stem cells from embryos necessarily kills them, thus raising difficult questions about the use of embryonic human material to save others. This article draws on previous controversies over embryo research and distinctions between intrinsic and symbolic moral status to analyze these issues. It argues that stem cell research with spare embryos produced during infertility treatment, or even embryos created specifically for research or therapeutic purposes, is ethically acceptable and should receive federal funding.

Stem cell research as innovation: expanding the ethical and policy conversation.

PubMed

Dresser, Rebecca

2010-01-01

Research using human embryonic stem cells raises an array of complex ethical issues, including, but by no means limited to, the moral status of developing human life. Unfortunately much of the public discussion fails to take into account this complexity. Advocacy for liberal and conservative positions on human embryonic stem cell research can be simplistic and misleading. Ethical concepts such as truth-telling, scientific integrity, and social justice should be part of the debate over federal support for human embryonic stem cell research. Moreover, the debate should be conducted in accord with principles of deliberative democracy, including respect for people holding competing views.

The potential use of stem cells derived from human amniotic fluid in renal diseases.

PubMed

Noronha, Irene L; Cavaglieri, Rita C; Janz, Felipe L; Duarte, Sergio A; Lopes, Marco A B; Zugaib, Marcelo; Bydlowski, Sergio P

2011-09-01

Amniotic fluid (AF) contains a variety of cell types derived from fetal tissues that can easily grow in culture. These cells can be obtained during amniocentesis for prenatal screening of fetal genetic diseases, usually performed during the second trimester of pregnancy. Of particular interest, some expanded sub-populations derived from AF cells are capable of extensive self-renewal and maintain prolonged undifferentiated proliferation, which are defining properties of stem cells. These human AF stem cells (hAFSCs) exhibit multilineage potential and can differentiate into the three germ layers. They have high proliferation rates and express mesenchymal and embryonic markers, but do not induce tumor formation. In this study, hAFSCs derived from amniocentesis performed at 16-20 weeks of pregnancy were isolated, grown in culture, and characterized by flow cytometry and by their potential ability to differentiate into osteogenic, adipogenic, and chondrogenic lineages. After 4-7 passages, 5 × 10 5 hAFSCs were inoculated under the kidney capsule of Wistar rats that were subjected to an experimental model of chronic renal disease, the 5/6 nephrectomy model (Nx). After 30 days, Nx rats treated with hAFSCs displayed significant reductions in blood pressure, proteinuria, macrophages, and α-smooth muscle actin expression compared with Nx animals. These preliminary results suggest that hAFSCs isolated and expanded from AF obtained by routine amniocentesis can promote renoprotection in the Nx model. Considering that the AF cells not used for fetal karyotyping are usually discarded, and that their use does not raise ethical issues, they may represent an alternative source of stem cells for cell therapy and regenerative medicine.

Directing adult human periodontal ligament-derived stem cells to retinal fate.

PubMed

Huang, Li; Liang, Jiajian; Geng, Yiqun; Tsang, Wai-Ming; Yao, Xiaowu; Jhanji, Vishal; Zhang, Mingzhi; Cheung, Herman S; Pang, Chi Pui; Yam, Gary Hin-Fai

2013-06-06

To investigate the retinal fate competence of human postnatal periodontal ligament (PDL)-derived stem cells (PDLSC) through a directed differentiation mimicking mammalian retinogenesis. Human teeth were collected from healthy subjects younger than 35 years old. Primary PDLSC were isolated by collagenase digestion and cultivated. PDLSC at passage 3 were cultured in the induction media containing Noggin (antagonist of bone morphogenic protein) and Dkk-1 (antagonist of Wnt/β-catenin signaling). Gene expression of neural crest cells, retinal progenitors, and retinal neurons, including photoreceptors, was revealed by RNA analyses, immunofluorescence, and flow cytometry. The neuronal-like property of differentiated cells in response to excitatory glutamate was examined by fluo-4-acetoxymethyl calcium imaging assay. Primary human PDLSC stably expressed marker genes for neural crest (Notch1, BMP2, Slug, Snail, nestin, and Tuj1), mesenchymal stem cell (CD44, CD90, and vimentin), and embryonic stem cell (c-Myc, Klf4, Nanog, and SSEA4). Under low attachment culture, PDLSC generated neurospheres expressing nestin, p75/NGFR, Pax6, and Tuj1 (markers of neural progenitors). When neurospheres were plated on Matrigel-coated surface, they exhibited rosette-like outgrowth. They expressed eye field transcription factors (Pax6, Rx, Lhx, Otx2). By flow cytometry, 94% of cells were Pax6(nuclear)Rx(+), indicative of retinal progenitors. At prolonged induction, they expressed photoreceptor markers (Nrl, rhodopsin and its kinase) and showed significant responsiveness to excitatory glutamate. Primary human PDLSC could be directed to retinal progenitors with competence for photoreceptor differentiation. Human neural crest-derived PDL is readily accessible and can be an ample autologous source of undifferentiated cells for retinal cell regeneration.

Variations in Glycogen Synthesis in Human Pluripotent Stem Cells with Altered Pluripotent States

PubMed Central

Chen, Richard J.; Zhang, Guofeng; Garfield, Susan H.; Shi, Yi-Jun; Chen, Kevin G.; Robey, Pamela G.; Leapman, Richard D.

2015-01-01

Human pluripotent stem cells (hPSCs) represent very promising resources for cell-based regenerative medicine. It is essential to determine the biological implications of some fundamental physiological processes (such as glycogen metabolism) in these stem cells. In this report, we employ electron, immunofluorescence microscopy, and biochemical methods to study glycogen synthesis in hPSCs. Our results indicate that there is a high level of glycogen synthesis (0.28 to 0.62 μg/μg proteins) in undifferentiated human embryonic stem cells (hESCs) compared with the glycogen levels (0 to 0.25 μg/μg proteins) reported in human cancer cell lines. Moreover, we found that glycogen synthesis was regulated by bone morphogenetic protein 4 (BMP-4) and the glycogen synthase kinase 3 (GSK-3) pathway. Our observation of glycogen bodies and sustained expression of the pluripotent factor Oct-4 mediated by the potent GSK-3 inhibitor CHIR-99021 reveals an altered pluripotent state in hPSC culture. We further confirmed glycogen variations under different naïve pluripotent cell growth conditions based on the addition of the GSK-3 inhibitor BIO. Our data suggest that primed hPSCs treated with naïve growth conditions acquire altered pluripotent states, similar to those naïve-like hPSCs, with increased glycogen synthesis. Furthermore, we found that suppression of phosphorylated glycogen synthase was an underlying mechanism responsible for altered glycogen synthesis. Thus, our novel findings regarding the dynamic changes in glycogen metabolism provide new markers to assess the energetic and various pluripotent states in hPSCs. The components of glycogen metabolic pathways offer new assays to delineate previously unrecognized properties of hPSCs under different growth conditions. PMID:26565809

Chemical Activation of the Hypoxia-Inducible Factor Reversibly Reduces Tendon Stem Cell Proliferation, Inhibits Their Differentiation, and Maintains Cell Undifferentiation

PubMed Central

Creo, Pasquale; Bergante, Sonia; Conforti, Erika; Banfi, Giuseppe

2018-01-01

Adult stem cell-based therapeutic approaches for tissue regeneration have been proposed for several years. However, adult stem cells are usually limited in number and difficult to be expanded in vitro, and they usually tend to quickly lose their potency with passages, as they differentiate and become senescent. Culturing stem cells under reduced oxygen tensions (below 21%) has been proposed as a tool to increase cell proliferation, but many studies reported opposite effects. In particular, cell response to hypoxia seems to be very stem cell type specific. Nonetheless, it is clear that a major role in this process is played by the hypoxia inducible factor (HIF), the master regulator of cell response to oxygen deprivation, which affects cell metabolism and differentiation. Herein, we report that a chemical activation of HIF in human tendon stem cells reduces their proliferation and inhibits their differentiation in a reversible and dose-dependent manner. These results support the notion that hypoxia, by activating HIF, plays a crucial role in preserving stem cells in an undifferentiated state in the “hypoxic niches” present in the tissue in which they reside before migrating in more oxygenated areas to heal a damaged tissue. PMID:29713352

Concentration dependent survival and neural differentiation of murine embryonic stem cells cultured on polyethylene glycol dimethacrylate hydrogels possessing a continuous concentration gradient of n-cadherin derived peptide His-Ala-Val-Asp-Lle.

PubMed

Lim, Hyun Ju; Mosley, Matthew C; Kurosu, Yuki; Smith Callahan, Laura A

2017-07-01

N-cadherin cell-cell signaling plays a key role in the structure and function of the nervous system. However, few studies have incorporated bioactive signaling from n-cadherin into tissue engineering matrices. The present study uses a continuous gradient approach in polyethylene glycol dimethacrylate hydrogels to identify concentration dependent effects of n-cadherin peptide, His-Ala-Val-Asp-Lle (HAVDI), on murine embryonic stem cell survival and neural differentiation. The n-cadherin peptide was found to affect the expression of pluripotency marker, alkaline phosphatase, in murine embryonic stem cells cultured on n-cadherin peptide containing hydrogels in a concentration dependent manner. Increasing n-cadherin peptide concentrations in the hydrogels elicited a biphasic response in neurite extension length and mRNA expression of neural differentiation marker, neuron-specific class III β-tubulin, in murine embryonic stem cells cultured on the hydrogels. High concentrations of n-cadherin peptide in the hydrogels were found to increase the expression of apoptotic marker, caspase 3/7, in murine embryonic stem cells compared to that of murine embryonic stem cell cultures on hydrogels containing lower concentrations of n-cadherin peptide. Increasing the n-cadherin peptide concentration in the hydrogels facilitated greater survival of murine embryonic stem cells exposed to increasing oxidative stress caused by hydrogen peroxide exposure. The combinatorial approach presented in this work demonstrates concentration dependent effects of n-cadherin signaling on mouse embryonic stem cell behavior, underscoring the need for the greater use of systematic approaches in tissue engineering matrix design in order to understand and optimize bioactive signaling in the matrix for tissue formation. Single cell encapsulation is common in tissue engineering matrices. This eliminates cellular access to cell-cell signaling. N-cadherin, a cell-cell signaling molecule, plays a vital role in the development of neural tissues, but has not been well studied as a bioactive signaling element in neural tissue engineering matrices. The present study uses a systematic continuous gradient approach to identify concentration dependent effects of n-cadherin derived peptide, HAVDI, on the survival and neural differentiation of murine embryonic stem cells. This work underscores the need for greater use to combinatorial strategies to understand the effect complex bioactive signaling, such as n-cadherin, and the need to optimize the concentration of such bioactive signaling within tissue engineering matrices for maximal cellular response. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

I-SceI-mediated double-strand break does not increase the frequency of homologous recombination at the Dct locus in mouse embryonic stem cells.

PubMed

Fenina, Myriam; Simon-Chazottes, Dominique; Vandormael-Pournin, Sandrine; Soueid, Jihane; Langa, Francina; Cohen-Tannoudji, Michel; Bernard, Bruno A; Panthier, Jean-Jacques

2012-01-01

Targeted induction of double-strand breaks (DSBs) at natural endogenous loci was shown to increase the rate of gene replacement by homologous recombination in mouse embryonic stem cells. The gene encoding dopachrome tautomerase (Dct) is specifically expressed in melanocytes and their precursors. To construct a genetic tool allowing the replacement of Dct gene by any gene of interest, we generated an embryonic stem cell line carrying the recognition site for the yeast I-SceI meganuclease embedded in the Dct genomic segment. The embryonic stem cell line was electroporated with an I-SceI expression plasmid, and a template for the DSB-repair process that carried sequence homologies to the Dct target. The I-SceI meganuclease was indeed able to introduce a DSB at the Dct locus in live embryonic stem cells. However, the level of gene targeting was not improved by the DSB induction, indicating a limited capacity of I-SceI to mediate homologous recombination at the Dct locus. These data suggest that homologous recombination by meganuclease-induced DSB may be locus dependent in mammalian cells.

Molecular Imaging of Human Embryonic Stem Cells Stably Expressing Human PET Reporter Genes After Zinc Finger Nuclease-Mediated Genome Editing.

PubMed

Wolfs, Esther; Holvoet, Bryan; Ordovas, Laura; Breuls, Natacha; Helsen, Nicky; Schönberger, Matthias; Raitano, Susanna; Struys, Tom; Vanbilloen, Bert; Casteels, Cindy; Sampaolesi, Maurilio; Van Laere, Koen; Lambrichts, Ivo; Verfaillie, Catherine M; Deroose, Christophe M

2017-10-01

Molecular imaging is indispensable for determining the fate and persistence of engrafted stem cells. Standard strategies for transgene induction involve the use of viral vectors prone to silencing and insertional mutagenesis or the use of nonhuman genes. Methods: We used zinc finger nucleases to induce stable expression of human imaging reporter genes into the safe-harbor locus adeno-associated virus integration site 1 in human embryonic stem cells. Plasmids were generated carrying reporter genes for fluorescence, bioluminescence imaging, and human PET reporter genes. Results: In vitro assays confirmed their functionality, and embryonic stem cells retained differentiation capacity. Teratoma formation assays were performed, and tumors were imaged over time with PET and bioluminescence imaging. Conclusion: This study demonstrates the application of genome editing for targeted integration of human imaging reporter genes in human embryonic stem cells for long-term molecular imaging. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

Ambivalent journeys of hope: embryonic stem cell therapy in a clinic in India.

PubMed

Prasad, Amit

2015-03-01

Stem cell therapy in non-Western countries such as India has received a lot of attention. Apart from media reports, there are a number of social science analyses of stem cell policy, therapy, and research, their ethical implications, and impact of advertising on patients. Nevertheless, in the media reports as well as in academic studies, experiences of patients, who undertake overseas journeys for stem cell therapy, have largely been either ignored or presented reductively, often as a "false hope." In this article, I analyze the experiences of patients and their "journeys of hope" to NuTech Mediworld, an embryonic stem cell therapy clinic in New Delhi, India. My analysis, which draws on my observations in the clinic and patients' experiences, instead of seeking to adjudicate whether embryonic stem cell therapy in clinics such as NuTech is right or wrong, true or false, focuses on how patients navigate and contest these concerns. I utilize Gilles Deleuze and Felix Guattari's "concepts," lines of flight and deterritorialization, to highlight how embryonic stem cell therapy's "political economy of hope" embodies deterritorialization of several "regimes of truth" and how these deterritorializations impact patients' experiences. © The Author(s) 2014.

Derivation of cat embryonic stem-like cells from in vitro-produced blastocysts on homologous and heterologous feeder cells.

PubMed

Gómez, M C; Serrano, M A; Pope, C Earle; Jenkins, J A; Biancardi, M N; López, M; Dumas, C; Galiguis, J; Dresser, B L

2010-09-01

The domestic cat is a focal mammalian species that is used as a model for developing assisted reproductive technologies for preserving endangered cats and for studying human diseases. The generation of stable characterized cat embryonic stem cells (ESC) lines to use as donor nuclei may help to improve the efficiency of interspecies somatic cell nuclear transfer for preserving endangered cats and allow the creation of knockout cell lines to generate knockout cats for studying function of specific genes related to human diseases. It will also enable the possibility of producing gametes in vitro from ESC of endangered cats. In the present study, we report the generation of cat embryonic stem-like (cESL) cells from blastocysts derived entirely in vitro. We generated 32 cESL cell lines from 331 in vitro derived blastocysts from which inner cell masses were isolated by immunosurgery or by a mechanical method. Inhibition of cat dermal fibroblast (CDF) proliferation after exposure to mitomycin-C was both dose and time dependent, where doses of 30 to 40 microg/mL for 5 h were most efficient. These dosages were higher than that required to inhibit cell proliferation of mouse fetal fibroblasts (MFF; 10 microg/mL for 2.5 h). Mitomycin-C did not significantly increase necrosis of cells from either species, and had an anti-proliferative effect at concentrations below cytotoxicity. A clear species-specific relationship between feeder layers and derivation of cESL cell lines was observed, where higher numbers of cESL cell lines were generated on homologous cat feeder layers (n = 26) than from those derived on heterologous mouse feeder layers (n = 6). Three cESL cell lines generated from immunosurgery and cultured on CDF maintained self-renewal and were morphologically undifferentiated for nine and twelve passages (69-102 days). These lines showed a tightly packed dome shaped morphology, exhibited alkaline phosphatase activity and immuno-expression of the pluripotent marker OCT-4 and surface marker SSEA-1. Primary colonies at P0 to P3 and cat blastocysts expressed transcription factors OCT-4, NANOG and SOX-2 and the proto-oncogene C-MYC. However, expression was at levels significantly lower than in vitro produced blastocysts. During culture, cESL colonies spontaneously differentiated into fibroblasts, cardiomyocytes, and embryoid bodies. Development of techniques to prevent differentiation of cESL cells will be essential for maintaining defined cell lines. Copyright 2010 Elsevier Inc. All rights reserved.

Present state and future perspectives of using pluripotent stem cells in toxicology research

PubMed Central

Löser, Peter

2011-01-01

The use of novel drugs and chemicals requires reliable data on their potential toxic effects on humans. Current test systems are mainly based on animals or in vitro–cultured animal-derived cells and do not or not sufficiently mirror the situation in humans. Therefore, in vitro models based on human pluripotent stem cells (hPSCs) have become an attractive alternative. The article summarizes the characteristics of pluripotent stem cells, including embryonic carcinoma and embryonic germ cells, and discusses the potential of pluripotent stem cells for safety pharmacology and toxicology. Special attention is directed to the potential application of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) for the assessment of developmental toxicology as well as cardio- and hepatotoxicology. With respect to embryotoxicology, recent achievements of the embryonic stem cell test (EST) are described and current limitations as well as prospects of embryotoxicity studies using pluripotent stem cells are discussed. Furthermore, recent efforts to establish hPSC-based cell models for testing cardio- and hepatotoxicity are presented. In this context, methods for differentiation and selection of cardiac and hepatic cells from hPSCs are summarized, requirements and implications with respect to the use of these cells in safety pharmacology and toxicology are presented, and future challenges and perspectives of using hPSCs are discussed. PMID:21225242

5-Azacitidine Monotherapy Followed by Related Haploidentical Hematopoietic Stem Cell Transplantation Achieves Durable Remission in a Pediatric Patient With Acute Undifferentiated Leukemia Refractory to High-Dose Chemotherapy.

PubMed

Polishchuk, Veronika; Khazal, Sajad; Berulava, Giorgi; Roth, Michael; Mahadeo, Kris M

2016-06-01

Patients with acute leukemias of undifferentiated lineage (AUL) generally have guarded prognosis. Here, we describe the first reported pediatric patient with AUL refractory to high-dose chemotherapy who achieved clinical remission with ALL maintenance therapy and 5-azacitidine. His induction remission was followed by consolidation with reduced toxicity haploidentical hematopoietic stem cell transplant (HSCT). At 9 months post-HSCT, the patient is alive and in remission. This combination therapy of remission induction with ALL maintenance therapy and 5-azacitidine and consolidation with reduced toxicity haploidentical HSCT is novel and promising for patients who lack conventional donors and are not candidates for myeloablative therapy. © 2016 Wiley Periodicals, Inc.

The roles of ERAS during cell lineage specification of mouse early embryonic development.

PubMed

Zhao, Zhen-Ao; Yu, Yang; Ma, Huai-Xiao; Wang, Xiao-Xiao; Lu, Xukun; Zhai, Yanhua; Zhang, Xiaoxin; Wang, Haibin; Li, Lei

2015-08-01

Eras encodes a Ras-like GTPase protein that was originally identified as an embryonic stem cell-specific Ras. ERAS has been known to be required for the growth of embryonic stem cells and stimulates somatic cell reprogramming, suggesting its roles on mouse early embryonic development. We now report a dynamic expression pattern of Eras during mouse peri-implantation development: its expression increases at the blastocyst stage, and specifically decreases in E7.5 mesoderm. In accordance with its expression pattern, the increased expression of Eras promotes cell proliferation through controlling AKT activation and the commitment from ground to primed state through ERK activation in mouse embryonic stem cells; and the reduced expression of Eras facilitates primitive streak and mesoderm formation through AKT inhibition during gastrulation. The expression of Eras is finely regulated to match its roles in mouse early embryonic development during which Eras expression is negatively regulated by the β-catenin pathway. Thus, beyond its well-known role on cell proliferation, ERAS may also play important roles in cell lineage specification during mouse early embryonic development. © 2015 The Authors.

Which bank? A guardian model for regulation of embryonic stem cell research in Australia.

PubMed

McLennan, A

2007-08-01

In late 2005 the Legislation Review: Prohibition of Human Cloning Act 2002 (Cth) and the Research Involving Human Embryos Act 2002 (Cth) recommended the establishment of an Australian stem cell bank. This article aims to address a lack of discussion of issues surrounding stem cell banking by suggesting possible answers to the questions of whether Australia should establish a stem cell bank and what its underlying philosophy and functions should be. Answers are developed through an analysis of regulatory, scientific and intellectual property issues relating to embryonic stem cell research in the United Kingdom, United States and Australia. This includes a detailed analysis of the United Kingdom Stem Cell Bank. It is argued that a "guardian" model stem cell bank should be established in Australia. This bank would aim to promote the maximum public benefit from human embryonic stem cell research by providing careful regulatory oversight and addressing ethical issues, while also facilitating research by addressing practical scientific concerns and intellectual property issues.

In vitro culture of bovine embryos in murine ES cell conditioned media negatively affects expression of pluripotency-related markers OCT4, SOX2 and SSEA1.

PubMed

Oliveira, C S; de Souza, M M; Saraiva, N Z; Tetzner, T A D; Lima, M R; Lopes, F L; Garcia, J M

2012-06-01

Despite extensive efforts, establishment of bovine embryonic stem (ES) cell lines has not been successful. We hypothesized that culture conditions for in vitro-produced (IVP) embryos, the most used source of inner cell mass (ICM) to obtain ES cells, might affect their undifferentiated state. Therefore, the aim of this work was to improve pluripotency of IVP blastocysts to produce suitable ICM for further culturing. We tested KSR and foetal calf serum (FCS) supplements in SOF medium and ES cell conditioned medium (CM) on IVC (groups: KSR, KSR CM, FCS and FCS CM). Cleavage and blastocyst rates were similar between all groups. Also, embryonic quality, assessed by apoptosis rates (TUNEL assay), total cell number and ICM percentage did not differ between experimental groups. However, expression of pluripotency-related markers was affected. We detected down-regulation of OCT3/4, SOX2 and SSEA1 in ICM of FCS CM blastocysts (p < 0.05). SOX2 gene expression revealed lower levels (p < 0.05) on KSR CM blastocysts and a remarkable variation in SOX2 mRNA levels on FCS-supplemented blastocysts. In conclusion, pluripotency-related markers tend to decrease after supplementation with ES cell CM, suggesting different mechanisms regulating mouse and bovine pluripotency. KSR supplementation did not differ from FCS, but FCS replacement by KSR may produce blastocysts with stable SOX2 gene expression levels. © 2011 Blackwell Verlag GmbH.

The role of nanotechnology in induced pluripotent and embryonic stem cells research.

PubMed

Chen, Lukui; Qiu, Rong; Li, Lushen

2014-12-01

This paper reviews the recent studies on development of nanotechnology in the field of induced pluripotent and embryonic stem cells. Stem cell therapy is a promising therapy that can improve the quality of life for patients with refractory diseases. However, this option is limited by the scarcity of tissues, ethical problem, and tumorigenicity. Nanotechnology is another promising therapy that can be used to mimic the extracellular matrix, label the implanted cells, and also can be applied in the tissue engineering. In this review, we briefly introduce implementation of nanotechnology in induced pluripotent and embryonic stem cells research. Finally, the potential application of nanotechnology in tissue engineering and regenerative medicine is also discussed.

High-Density ZnO Nanowires as a Reversible Myogenic-Differentiation Switch.

PubMed

Errico, Vito; Arrabito, Giuseppe; Fornetti, Ersilia; Fuoco, Claudia; Testa, Stefano; Saggio, Giovanni; Rufini, Stefano; Cannata, Stefano; Desideri, Alessandro; Falconi, Christian; Gargioli, Cesare

2018-04-25

Mesoangioblasts are outstanding candidates for stem-cell therapy and are already being explored in clinical trials. However, a crucial challenge in regenerative medicine is the limited availability of undifferentiated myogenic progenitor cells because growth is typically accompanied by differentiation. Here reversible myogenic-differentiation switching during proliferation is achieved by functionalizing the glass substrate with high-density ZnO nanowires (NWs). Specifically, mesoangioblasts grown on ZnO NWs present a spherical viable undifferentiated cell state without lamellopodia formation during the entire observation time (8 days). Consistently, the myosin heavy chain, typically expressed in skeletal muscle tissue and differentiated myogenic progenitors, is completely absent. Remarkably, NWs do not induce any damage while they reversibly block differentiation, so that the differentiation capabilities are completely recovered upon cell removal from the NW-functionalized substrate and replating on standard culture glass. This is the first evidence of a reversible myogenic-differentiation switch that does not affect the viability. These results can be the first step toward for the in vitro growth of a large number of undifferentiated stem/progenitor cells and therefore can represent a breakthrough for cell-based therapy and tissue engineering.

Pioneer factors, genetic competence, and inductive signaling: programming liver and pancreas progenitors from the endoderm.

PubMed

Zaret, K S; Watts, J; Xu, J; Wandzioch, E; Smale, S T; Sekiya, T

2008-01-01

The endoderm is a multipotent progenitor cell population in the embryo that gives rise to the liver, pancreas, and other cell types and provides paradigms for understanding cell-type specification. Studies of isolated embryo tissue cells and genetic approaches in vivo have defined fibroblast growth factor/mitogen-activated protein kinase (FGF/MAPK) and bone morphogenetic protein (BMP) signaling pathways that induce liver and pancreatic fates in the endoderm. In undifferentiated endoderm cells, the FoxA and GATA transcription factors are among the first to engage silent genes, helping to endow competence for cell-type specification. FoxA proteins can bind their target sites in highly compacted chromatin and open up the local region for other factors to bind; hence, they have been termed "pioneer factors." We recently found that FoxA proteins remain bound to chromatin in mitosis, as an epigenetic mark. In embryonic stem cells, which lack FoxA, FoxA target sites can be occupied by FoxD3, which in turn helps to maintain a local demethylation of chromatin. By these means, a cascade of Fox factors helps to endow progenitor cells with the competence to activate genes in response to tissue-inductive signals. Understanding such epigenetic mechanisms for transcriptional competence coupled with knowledge of the relevant signals for cell-type specification should greatly facilitate efforts to predictably differentiate stem cells to liver and pancreatic fates.

Doxycycline supplementation allows for the culture of human ESCs/iPSCs with media changes at 3-day intervals.

PubMed

Chang, Mi-Yoon; Oh, Boram; Rhee, Yong-Hee; Lee, Sang-Hun

2015-11-01

Culturing human embryonic stem and induced pluripotent stem cells (hESCs/iPSCs) is one of the most costly and labor-intensive tissue cultures, as media containing expensive factors/cytokines should be changed every day to maintain and propagate undifferentiated hESCs/iPSCs in vitro. We recently reported that doxycycline, an anti-bacterial agent, had dramatic effects on hESC/iPSC survival and promoted self-renewal. In this study, we extended the effects of doxycycline to a more practical issue to save cost and labor in hESC/iPSC cultures. Regardless of cultured cell conditions, hESCs/iPSCs in doxycycline-supplemented media were viable and proliferating for at least 3 days without media change, while none or few viable cells were detected in the absence of doxycycline in the same conditions. Thus, hESCs/iPSCs supplemented with doxycycline can be cultured for a long period of time with media changes at 3-day intervals without altering their self-renewal and pluripotent properties, indicating that doxycycline supplementation can reduce the frequency of media changes and the amount of media required by 1/3. These findings strongly encourage the use of doxycycline to save cost and labor in culturing hESCs/iPSCs. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Nuclear receptor TLX regulates cell cycle progression in neural stem cells of the developing brain.

PubMed

Li, Wenwu; Sun, Guoqiang; Yang, Su; Qu, Qiuhao; Nakashima, Kinichi; Shi, Yanhong

2008-01-01

TLX is an orphan nuclear receptor that is expressed exclusively in vertebrate forebrains. Although TLX is known to be expressed in embryonic brains, the mechanism by which it influences neural development remains largely unknown. We show here that TLX is expressed specifically in periventricular neural stem cells in embryonic brains. Significant thinning of neocortex was observed in embryonic d 14.5 TLX-null brains with reduced nestin labeling and decreased cell proliferation in the germinal zone. Cell cycle analysis revealed both prolonged cell cycles and increased cell cycle exit in TLX-null embryonic brains. Increased expression of a cyclin-dependent kinase inhibitor p21 and decreased expression of cyclin D1 provide a molecular basis for the deficiency of cell cycle progression in embryonic brains of TLX-null mice. Furthermore, transient knockdown of TLX by in utero electroporation led to precocious cell cycle exit and differentiation of neural stem cells followed by outward migration. Together these results indicate that TLX plays an important role in neural development by regulating cell cycle progression and exit of neural stem cells in the developing brain.

Nuclear Receptor TLX Regulates Cell Cycle Progression in Neural Stem Cells of the Developing Brain

PubMed Central

Li, Wenwu; Sun, Guoqiang; Yang, Su; Qu, Qiuhao; Nakashima, Kinichi; Shi, Yanhong

2008-01-01

TLX is an orphan nuclear receptor that is expressed exclusively in vertebrate forebrains. Although TLX is known to be expressed in embryonic brains, the mechanism by which it influences neural development remains largely unknown. We show here that TLX is expressed specifically in periventricular neural stem cells in embryonic brains. Significant thinning of neocortex was observed in embryonic d 14.5 TLX-null brains with reduced nestin labeling and decreased cell proliferation in the germinal zone. Cell cycle analysis revealed both prolonged cell cycles and increased cell cycle exit in TLX-null embryonic brains. Increased expression of a cyclin-dependent kinase inhibitor p21 and decreased expression of cyclin D1 provide a molecular basis for the deficiency of cell cycle progression in embryonic brains of TLX-null mice. Furthermore, transient knockdown of TLX by in utero electroporation led to precocious cell cycle exit and differentiation of neural stem cells followed by outward migration. Together these results indicate that TLX plays an important role in neural development by regulating cell cycle progression and exit of neural stem cells in the developing brain. PMID:17901127

FOXM1 in sarcoma: role in cell cycle, pluripotency genes and stem cell pathways.

PubMed

Kelleher, Fergal C; O'Sullivan, Hazel

2016-07-05

FOXM1 is a pro-proliferative transcription factor that promotes cell cycle progression at the G1-S, and G2-M transitions. It is activated by phosphorylation usually mediated by successive cyclin - cyclin dependent kinase complexes, and is highly expressed in sarcoma. p53 down regulates FOXM1 and FOXM1 inhibition is also partly dependent on Rb and p21. Abnormalities of p53 or Rb are frequent in sporadic sarcomas with bone or soft tissue sarcoma, accounting for 36% of index cancers in the high penetrance TP53 germline disorder, Li-Fraumeni syndrome.FOXM1 stimulates transcription of pluripotency related genes including SOX2, KLF4, OCT4, and NANOG many of which are important in sarcoma, a disorder of mesenchymal stem cell/ partially committed progenitor cells. In a selected specific, SOX2 is uniformly expressed in synovial sarcoma. Embryonic pathways preferentially used in stem cell such as Hippo, Hedgehog, and Wnt dominate in FOXM1 stoichiometry to alter rates of FOXM1 production or degradation. In undifferentiated pleomorphic sarcoma, liposarcoma, and fibrosarcoma, dysregulation of the Hippo pathway increases expression of the effector co-transcriptional activator Yes-Associated Protein (YAP). A complex involving YAP and the transcription factor TEAD elevates FOXM1 in these sarcoma subtypes. In another scenario 80% of desmoid tumors have nuclear localization of β-catenin, the Wnt pathway effector molecule. Thiazole antibiotics inhibit FOXM1 and because they have an auto-regulator loop FOXM1 expression is also inhibited. Current systemic treatment of sarcoma is of limited efficacy and inhibiting FOXM1 represents a potential new strategy.

Abrogation of E-cadherin-mediated cellular aggregation allows proliferation of pluripotent mouse embryonic stem cells in shake flask bioreactors.

PubMed

Mohamet, Lisa; Lea, Michelle L; Ward, Christopher M

2010-09-23

A fundamental requirement for the exploitation of embryonic stem (ES) cells in regenerative medicine is the ability to reproducibly derive sufficient numbers of cells of a consistent quality in a cost-effective manner. However, undifferentiated ES cells are not ideally suited to suspension culture due to the formation of cellular aggregates, ultimately limiting scalability. Significant advances have been made in recent years in the culture of ES cells, including automated adherent culture and suspension microcarrier or embryoid body bioreactor culture. However, each of these methods exhibits specific disadvantages, such as high cost, additional downstream processes or reduced cell doubling times. Here we show that abrogation of the cell surface protein E-cadherin, using either gene knockout (Ecad-/-) or the neutralising antibody DECMA-1 (EcadAb), allows culture of mouse ES cells as a near-single cell suspension in scalable shake flask culture over prolonged periods without additional media supplements. Both Ecad-/- and EcadAb ES cells exhibited adaptation phases in suspension culture, with optimal doubling times of 7.3 h±0.9 and 15.6 h±4.7 respectively and mean-fold increase in viable cell number of 95.1±2.0 and 16±0.9-fold over 48 h. EcadAb ES cells propagated as a dispersed cell suspension for 15 d maintained expression of pluripotent markers, exhibited a normal karyotype and high viability. Subsequent differentiation of EcadAb ES cells resulted in expression of transcripts and proteins associated with the three primary germ layers. This is the first demonstration of the culture of pluripotent ES cells as a near-single cell suspension in a manual fed-batch shake flask bioreactor and represents a significant improvement on current ES cell culture techniques. Whilst this proof-of-principle method would be useful for the culture of human ES and iPS cells, further steps are necessary to increase cell viability of hES cells in suspension.

Collagen-IV supported embryoid bodies formation and differentiation from buffalo (Bubalus bubalis) embryonic stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taru Sharma, G., E-mail: gts553@gmail.com; Dubey, Pawan K.; Verma, Om Prakash

Graphical abstract: EBs formation, characterization and expression of germinal layers marker genes of in vivo developed teratoma using four different types of extracellular matrices. Highlights: Black-Right-Pointing-Pointer Collagen-IV matrix is found cytocompatible for EBs formation and differentiation. Black-Right-Pointing-Pointer Established 3D microenvironment for ES cells development and differentiation into three germ layers. Black-Right-Pointing-Pointer Collagen-IV may be useful as promising candidate for ES cells based therapeutic applications. -- Abstract: Embryoid bodies (EBs) are used as in vitro model to study early extraembryonic tissue formation and differentiation. In this study, a novel method using three dimensional extracellular matrices for in vitro generation of EBsmore » from buffalo embryonic stem (ES) cells and its differentiation potential by teratoma formation was successfully established. In vitro derived inner cell masses (ICMs) of hatched buffalo blastocyst were cultured on buffalo fetal fibroblast feeder layer for primary cell colony formation. For generation of EBs, pluripotent ES cells were seeded onto four different types of extracellular matrices viz; collagen-IV, laminin, fibronectin and matrigel using undifferentiating ES cell culture medium. After 5 days of culture, ESCs gradually grew into aggregates and formed simple EBs having circular structures. Twenty-six days later, they formed cystic EBs over collagen matrix with higher EBs formation and greater proliferation rate as compared to other extracellular matrices. Studies involving histological observations, fluorescence microscopy and RT-PCR analysis of the in vivo developed teratoma revealed that presence of all the three germ layer derivatives viz. ectoderm (NCAM), mesoderm (Flk-1) and endoderm (AFP). In conclusion, the method described here demonstrates a simple and cost-effective way of generating EBs from buffalo ES cells. Collagen-IV matrix was found cytocompatible as it supported buffalo EBs formation, their subsequent differentiation could prove to be useful as promising candidate for ES cells based therapeutic applications.« less

Alcohol-Induced Molecular Dysregulation in Human Embryonic Stem Cell-Derived Neural Precursor Cells

PubMed Central

Kim, Yi Young; Roubal, Ivan; Lee, Youn Soo; Kim, Jin Seok; Hoang, Michael; Mathiyakom, Nathan; Kim, Yong

2016-01-01

Adverse effect of alcohol on neural function has been well documented. Especially, the teratogenic effect of alcohol on neurodevelopment during embryogenesis has been demonstrated in various models, which could be a pathologic basis for fetal alcohol spectrum disorders (FASDs). While the developmental defects from alcohol abuse during gestation have been described, the specific mechanisms by which alcohol mediates these injuries have yet to be determined. Recent studies have shown that alcohol has significant effect on molecular and cellular regulatory mechanisms in embryonic stem cell (ESC) differentiation including genes involved in neural development. To test our hypothesis that alcohol induces molecular alterations during neural differentiation we have derived neural precursor cells from pluripotent human ESCs in the presence or absence of ethanol treatment. Genome-wide transcriptomic profiling identified molecular alterations induced by ethanol exposure during neural differentiation of hESCs into neural rosettes and neural precursor cell populations. The Database for Annotation, Visualization and Integrated Discovery (DAVID) functional analysis on significantly altered genes showed potential ethanol’s effect on JAK-STAT signaling pathway, neuroactive ligand-receptor interaction, Toll-like receptor (TLR) signaling pathway, cytokine-cytokine receptor interaction and regulation of autophagy. We have further quantitatively verified ethanol-induced alterations of selected candidate genes. Among verified genes we further examined the expression of P2RX3, which is associated with nociception, a peripheral pain response. We found ethanol significantly reduced the level of P2RX3 in undifferentiated hESCs, but induced the level of P2RX3 mRNA and protein in hESC-derived NPCs. Our result suggests ethanol-induced dysregulation of P2RX3 along with alterations in molecules involved in neural activity such as neuroactive ligand-receptor interaction may be a molecular event associated with alcohol-related peripheral neuropathy of an enhanced nociceptive response. PMID:27682028

Down regulation of ITGA4 and ITGA5 genes after formation of 3D spherules by human Wharton's jelly stem cells (hWJSCs).

PubMed

Mostafavi-Pour, Zohreh; Ashrafi, Mohammad Reza; Talaei-Khozani, Tahereh

2018-06-01

Human Wharton's jelly mesenchymal stem cells (hWJSCs) are multipotent stem cells that could be aggregated into 3D spherules. ITGA4 and ITGA5 genes encode α4 and α5 subunits of integrins, respectively. In this study, we analyzed expression levels of ITGA4 and ITGA5 gene mRNAs in undifferentiated and 3D spherules forming hWJSCs in order to determine their expression pattern for possible future treatment of cancer cells in a co-culture fashion. For the purpose of obtaining hWJSCs, umbilical cords were collected from patients with caesarian section at full term delivery. The cells were then characterized according to cell surface markers using flow cytometry. Furthermore pluripotency of the obtained cells was verified. Subsequently the cells were aggregated in 3D spherules using hanging drop cultures. Expression levels of ITGA4 and ITGA5 gene mRNAs were determined by RT-PCR and Real time PCR, both in the initial undifferentiated cells and those aggregated in the spherules. The obtained hWJSCs demonstrated pluripotency, differentiating to adipogenic and osteogenic cells. They also expressed mesenchymal stem cell surface markers. Following the aggregation of these cells and formation of 3D spherules, mRNA expression levels of both genes were significantly reduced (P < 0.05) compared with the initial undifferentiated state. The results of this study demonstrated that aggregation of hWJSCs into spherules alters their expression of ITGA4 and ITGA5. The implications of such an alteration would require further research.

LASP-01: Distribution of Mouse Embryonic Stem Cells Expressing MicroRNAs | Frederick National Laboratory for Cancer Research

Cancer.gov

The Laboratory Animal Sciences Program manages the expansion, processing, and distribution of1,501 genetically engineered mouse embryonic stem cell (mESC) linesharboring conditional microRNA transgenes. The Laboratory Animal Sciences Prog

Chromatin in embryonic stem cell neuronal differentiation.

PubMed

Meshorer, E

2007-03-01

Chromatin, the basic regulatory unit of the eukaryotic genetic material, is controlled by epigenetic mechanisms including histone modifications, histone variants, DNA methylation and chromatin remodeling. Cellular differentiation involves large changes in gene expression concomitant with alterations in genome organization and chromatin structure. Such changes are particularly evident in self-renewing pluripotent embryonic stem cells, which begin, in terms of cell fate, as a tabula rasa, and through the process of differentiation, acquire distinct identities. Here I describe the changes in chromatin that accompany neuronal differentiation, particularly of embryonic stem cells, and discuss how chromatin serves as the master regulator of cellular destiny.

Human embryonic stem cell research: an intercultural perspective.

PubMed

Walters, LeRoy

2004-03-01

In 1998, researchers discovered that embryonic stem cells could be derived from early human embryos. This discovery has raised a series of ethical and public-policy questions that are now being confronted by multiple international organizations, nations, cultures, and religious traditions. This essay surveys policies for human embryonic stem cell research in four regions of the world, reports on the recent debate at the United Nations about one type of such research, and reviews the positions that various religious traditions have adopted regarding this novel type of research. In several instances the religious traditions seem to have influenced the public-policy debates.

Epigenetic modulation by TFII-I during embryonic stem cell differentiation.

PubMed

Bayarsaihan, Dashzeveg; Makeyev, Aleksandr V; Enkhmandakh, Badam

2012-10-01

TFII-I transcription factors play an essential role during early vertebrate embryogenesis. Genome-wide mapping studies by ChIP-seq and ChIP-chip revealed that TFII-I primes multiple genomic loci in mouse embryonic stem cells and embryonic tissues. Moreover, many TFII-I-bound regions co-localize with H3K4me3/K27me3 bivalent chromatin within the promoters of lineage-specific genes. This minireview provides a summary of current knowledge regarding the function of TFII-I in epigenetic control of stem cell differentiation. Copyright © 2012 Wiley Periodicals, Inc.

Efficient femtosecond driven SOX 17 delivery into mouse embryonic stem cells: differentiation studies

NASA Astrophysics Data System (ADS)

Thobakgale, Lebogang; Manoto, Sello Lebohang; Lemboumba, Satuurnin Ombinda; Maaza, Malik; Mthunzi-Kufa, Patience

2017-02-01

Embryonic stem cells have great promise in regenerative medicine because of their ability to self-renew and differentiate into various cell types. Delivery of therapeutic genes into cells has already been achieved using of chemical agents and viral vectors with high transfection efficiencies. However, these methods have also been documented as toxic and in the latter case they can cause latent cell infections. In this study we use femtosecond laser pulses to optically deliver genetic material in mouse embryonic stem cells. Femtosecond laser pulses in contrast to the conventional approach, minimises the risk of unwanted side effects because photons are used to create transient pores on the membrane which allow free entry of molecules with no need for delivery agents. Using an Olympus microscope, fluorescence imaging of the samples post irradiation was performed and decreased expression of stage specific embryonic antigen one (SSEA-1) consistent with on-going cellular differentiation was observed. Our results also show that femtosecond laser pulses were effective in delivering SOX 17 plasmid DNA (pSOX17) which resulted in the differentiation of mouse embryonic stem cells into endoderm cells. We thus concluded that laser transfection of stem cells for the purpose of differentiation, holds potential for applications in tissue engineering as a method of generating new cell lines.

Establishment of autologous embryonic stem cells derived from preantral follicle culture and oocyte parthenogenesis.

PubMed

Lee, Seung Tae; Choi, Mun Hwan; Lee, Eun Ju; Gong, Seung Pyo; Jang, Mi; Park, Sang Hyun; Jee, Hyang; Kim, Dae Yong; Han, Jae Yong; Lim, Jeong Mook

2008-11-01

To evaluate whether autologous embryonic stem cells can be established without generating clone embryos. Prospective model study. Gamete and stem cell biotechnology laboratory in Seoul National University, Seoul, Korea. F1 hybrid B6D2F1 mice. Preantral follicles were cultured, and oocytes matured in the follicles were parthenogenetically activated. Preimplantation development and stem cell characterization. More intrafollicular oocytes that were retrieved from secondary follicles matured and developed into blastocysts after parthenogenesis than those that were retrieved from primary follicles. Of those 35 blastocysts derived from 193 parthenotes, one line of colony-forming cells was established from the culturing of early secondary follicles. The established cells were positive for embryonic stem cell-specific markers and had normal diploid karyotype and telomerase activity. They differentiated into embryoid bodies in vitro and teratomas in vivo. Inducible differentiation of the established cells into neuronal lineage cells also was possible. Autologous embryonic stem cells can be established by preantral follicle culture and oocyte parthenogenesis. A combined technique of follicle culture and oocyte parthenogenesis that does not use developmentally competent oocytes has the potential to replace somatic cell nuclear transfer for autologous cell therapy.

Glycosyltransferase ST6GAL1 contributes to the regulation of pluripotency in human pluripotent stem cells

PubMed Central

Wang, Yu-Chieh; Stein, Jason W.; Lynch, Candace L.; Tran, Ha T.; Lee, Chia-Yao; Coleman, Ronald; Hatch, Adam; Antontsev, Victor G.; Chy, Hun S.; O’Brien, Carmel M.; Murthy, Shashi K.; Laslett, Andrew L.; Peterson, Suzanne E.; Loring, Jeanne F.

2015-01-01

Many studies have suggested the significance of glycosyltransferase-mediated macromolecule glycosylation in the regulation of pluripotent states in human pluripotent stem cells (hPSCs). Here, we observed that the sialyltransferase ST6GAL1 was preferentially expressed in undifferentiated hPSCs compared to non-pluripotent cells. A lectin which preferentially recognizes α-2,6 sialylated galactosides showed strong binding reactivity with undifferentiated hPSCs and their glycoproteins, and did so to a much lesser extent with differentiated cells. In addition, downregulation of ST6GAL1 in undifferentiated hPSCs led to a decrease in POU5F1 (also known as OCT4) protein and significantly altered the expression of many genes that orchestrate cell morphogenesis during differentiation. The induction of cellular pluripotency in somatic cells was substantially impeded by the shRNA-mediated suppression of ST6GAL1, partially through interference with the expression of endogenous POU5F1 and SOX2. Targeting ST6GAL1 activity with a sialyltransferase inhibitor during cell reprogramming resulted in a dose-dependent reduction in the generation of human induced pluripotent stem cells (hiPSCs). Collectively, our data indicate that ST6GAL1 plays an important role in the regulation of pluripotency and differentiation in hPSCs, and the pluripotent state in human cells can be modulated using pharmacological tools to target sialyltransferase activity. PMID:26304831

Optimization of a serum-free culture medium for mouse embryonic stem cells using design of experiments (DoE) methodology.

PubMed

Knöspel, Fanny; Schindler, Rudolf K; Lübberstedt, Marc; Petzolt, Stephanie; Gerlach, Jörg C; Zeilinger, Katrin

2010-12-01

The in vitro culture behaviour of embryonic stem cells (ESC) is strongly influenced by the culture conditions. Current culture media for expansion of ESC contain some undefined substances. Considering potential clinical translation work with such cells, the use of defined media is desirable. We have used Design of Experiments (DoE) methods to investigate the composition of a serum-free chemically defined culture medium for expansion of mouse embryonic stem cells (mESC). Factor screening analysis according to Plackett-Burman revealed that insulin and leukaemia inhibitory factor (LIF) had a significant positive influence on the proliferation activity of the cells, while zinc and L: -cysteine reduced the cell growth. Further analysis using minimum run resolution IV (MinRes IV) design indicates that following factor adjustment LIF becomes the main factor for the survival and proliferation of mESC. In conclusion, DoE screening assays are applicable to develop and to refine culture media for stem cells and could also be employed to optimize culture media for human embryonic stem cells (hESC).

Stem cells: sources and applications.

PubMed

Vats, A; Tolley, N S; Polak, J M; Buttery, L D K

2002-08-01

Tissue engineering is a multidisciplinary area of research aimed at regeneration of tissues and restoration of function of organs through implantation of cells/tissues grown outside the body, or stimulating cells to grow into implanted matrix. In this short review, some of the most recent developments in the use of stem cells for tissue repair and regeneration will be discussed. There is no doubt that stem cells derived from adult and embryonic sources hold great therapeutic potential but it is clear that there is still much research required before their use is commonplace. There is much debate over adult versus embryonic stem cells and whether both are required. It is probably too early to disregard one or other of these cell sources. With regard to embryonic stem cells, the major concern relates to the ethics of their creation and the proposed practice of therapeutic cloning.

Functional characterization of human pluripotent stem cell-derived arterial endothelial cells.

PubMed

Zhang, Jue; Chu, Li-Fang; Hou, Zhonggang; Schwartz, Michael P; Hacker, Timothy; Vickerman, Vernella; Swanson, Scott; Leng, Ning; Nguyen, Bao Kim; Elwell, Angela; Bolin, Jennifer; Brown, Matthew E; Stewart, Ron; Burlingham, William J; Murphy, William L; Thomson, James A

2017-07-25

Here, we report the derivation of arterial endothelial cells from human pluripotent stem cells that exhibit arterial-specific functions in vitro and in vivo. We combine single-cell RNA sequencing of embryonic mouse endothelial cells with an EFNB2-tdTomato/EPHB4-EGFP dual reporter human embryonic stem cell line to identify factors that regulate arterial endothelial cell specification. The resulting xeno-free protocol produces cells with gene expression profiles, oxygen consumption rates, nitric oxide production levels, shear stress responses, and TNFα-induced leukocyte adhesion rates characteristic of arterial endothelial cells. Arterial endothelial cells were robustly generated from multiple human embryonic and induced pluripotent stem cell lines and have potential applications for both disease modeling and regenerative medicine.

Gene targeting in embryonic stem cells, II: conditional technologies

USDA-ARS?s Scientific Manuscript database

Genome modification via transgenesis has allowed researchers to link genotype and phenotype as an alternative approach to the characterization of random mutations through evolution. The synergy of technologies from the fields of embryonic stem (ES) cells, gene knockouts, and protein-mediated recombi...

Stem cells: science, policy, and ethics

PubMed Central

Fischbach, Gerald D.; Fischbach, Ruth L.

2004-01-01

Human embryonic stem cells offer the promise of a new regenerative medicine in which damaged adult cells can be replaced with new cells. Research is needed to determine the most viable stem cell lines and reliable ways to promote the differentiation of pluripotent stem cells into specific cell types (neurons, muscle cells, etc.). To create new cell lines, it is necessary to destroy preimplantation blastocysts. This has led to an intense debate that threatens to limit embryonic stem cell research. The profound ethical issues raised call for informed, dispassionate debate. PMID:15545983

Cell differentiation: therapeutical challenges in diabetes.

PubMed

Roche, Enrique; Vicente-Salar, Nestor; Arribas, Maribel; Paredes, Beatriz

2012-01-01

Stem cells, derived from either embryonic or adult tissues, are considered to be potential sources of insulin-secreting cells to be transplanted into type 1 and advanced stages of type 2 diabetic patients. Many laboratories have considered this possibility, resulting in a large amount of published protocols, with a wide degree of complexity among them. Our group was the first to report that it was possible to obtain insulin-secreting cells from mouse embryonic stem cells, proving the feasibility of this new challenge. The same observation was immediately reported using human embryonic stem cells. However, the resulting cell product was not properly characterised, affecting the reproducibility of the protocol by other groups. A more elaborated protocol was developed by Lumelsky and co-workers, demonstrating that neuroectodermal cells could be an alternative source for insulin-producing cells. However, the resulting cells of this protocol produced low amounts of the hormone. This aimed other groups to perform key changes in order to improve the insulin content of the resulting cells. Recently, Baetge's group has published a new protocol based on the knowledge accumulated in pancreatic development. In this protocol, human embryonic stem cells were differentiated into islet-like structures through a five step protocol, emulating the key steps during embryonic development of the endocrine pancreas. The final cell product, however, seemed to be in an immature state, thus further improvement is required. Despite this drawback, the protocol represents the culmination of work performed by different groups and offers new research challenges for the investigators in this exciting field. Concerning adult stem cells, the possibility of identifying pancreatic precursors or of reprogramming extrapancreatic derived cells are key possibilities that may circumvent the problems that appear when using embryonic stem cells, such as immune rejection and tumour formation.

Niche players

PubMed Central

Seandel, Marco; Falciatori, Ilaria; Shmelkov, Sergey V.; Kim, Jiyeon; James, Daylon; Rafii, Shahin

2010-01-01

The undifferentiated spermatogonia of adult mouse testes are composed of both true stem cells and committed progenitors. It is unclear what normally prevents these adult germ cells from manifesting multipotency. The critical elements of the spermatogonial stem cell niche, while poorly understood, are thought to be composed of Sertoli cells with several other somatic cell types in close proximity. We recently discovered a novel orphan G-protein coupled receptor (GPR125) that is restricted to undifferentiated spermatogonia within the testis. GPR125 expression was maintained when the progenitor cells were extracted from the in vivo niche and propagated under growth conditions that recapitulate key elements of the niche. Such conditions preserved the ability of the cells to generate multipotent derivatives, known as multipotent adult spermatogonial derived progenitor cells (MASCs). Upon differentiation, the latter produced a variety tissues including functional endothelium, illustrating the potential applications of such cells. Thus, GPR125 represents a novel target for purifying adult stem and progenitors from tissues, with the goal of developing autologous multipotent cell lines. PMID:18256534

Craniopharyngiomas express embryonic stem cell markers (SOX2, OCT4, KLF4, and SOX9) as pituitary stem cells but do not coexpress RET/GFRA3 receptors.

PubMed

Garcia-Lavandeira, Montserrat; Saez, Carmen; Diaz-Rodriguez, Esther; Perez-Romero, Sihara; Senra, Ana; Dieguez, Carlos; Japon, Miguel A; Alvarez, Clara V

2012-01-01

Adult stem cells maintain some markers expressed by embryonic stem cells and express other specific markers depending on the organ where they reside. Recently, stem/progenitor cells in the rodent and human pituitary have been characterized as expressing GFRA2/RET, PROP1, and stem cell markers such as SOX2 and OCT4 (GPS cells). Our objective was to detect other specific markers of the pituitary stem cells and to investigate whether craniopharyngiomas (CRF), a tumor potentially derived from Rathke's pouch remnants, express similar markers as normal pituitary stem cells. We conducted mRNA and Western blot studies in pituitary extracts, and immunohistochemistry and immunofluorescence on sections from normal rat and human pituitaries and 20 CRF (18 adamantinomatous and two papillary). Normal pituitary GPS stem cells localized in the marginal zone (MZ) express three key embryonic stem cell markers, SOX2, OCT4, and KLF4, in addition to SOX9 and PROP1 and β-catenin overexpression. They express the RET receptor and its GFRA2 coreceptor but also express the coreceptor GFRA3 that could be detected in the MZ of paraffin pituitary sections. CRF maintain the expression of SOX2, OCT4, KLF4, SOX9, and β-catenin. However, RET and GFRA3 expression was altered in CRF. In 25% (five of 20), both RET and GFRA3 were detected but not colocalized in the same cells. The other 75% (15 of 20) lose the expression of RET, GFRA3, or both proteins simultaneously. Human pituitary adult stem/progenitor cells (GPS) located in the MZ are characterized by expression of embryonic stem cell markers SOX2, OCT4, and KLF4 plus the specific pituitary embryonic factor PROP1 and the RET system. Redundancy in RET coreceptor expression (GFRA2 and GFRA3) suggest an important systematic function in their physiological behavior. CRF share the stem cell markers suggesting a common origin with GPS. However, the lack of expression of the RET/GFRA system could be related to the cell mislocation and deregulated growth of CRF.

Selection of stable reference genes for quantitative rt-PCR comparisons of mouse embryonic and extra-embryonic stem cells.

PubMed

Veazey, Kylee J; Golding, Michael C

2011-01-01

Isolation and culture of both embryonic and tissue specific stem cells provide an enormous opportunity to study the molecular processes driving development. To gain insight into the initial events underpinning mammalian embryogenesis, pluripotent stem cells from each of the three distinct lineages present within the preimplantation blastocyst have been derived. Embryonic (ES), trophectoderm (TS) and extraembryonic endoderm (XEN) stem cells possess the developmental potential of their founding lineages and seemingly utilize distinct epigenetic modalities to program gene expression. However, the basis for these differing cellular identities and epigenetic properties remain poorly defined.Quantitative reverse transcription-polymerase chain reaction (qPCR) is a powerful and efficient means of rapidly comparing patterns of gene expression between different developmental stages and experimental conditions. However, careful, empirical selection of appropriate reference genes is essential to accurately measuring transcriptional differences. Here we report the quantitation and evaluation of fourteen commonly used references genes between ES, TS and XEN stem cells. These included: Actb, B2m, Hsp70, Gapdh, Gusb, H2afz, Hk2, Hprt, Pgk1, Ppia, Rn7sk, Sdha, Tbp and Ywhaz. Utilizing three independent statistical analysis, we identify Pgk1, Sdha and Tbp as the most stable reference genes between each of these stem cell types. Furthermore, we identify Sdha, Tbp and Ywhaz as well as Ywhaz, Pgk1 and Hk2 as the three most stable reference genes through the in vitro differentiation of embryonic and trophectoderm stem cells respectively.Understanding the transcriptional and epigenetic regulatory mechanisms controlling cellular identity within these distinct stem cell types provides essential insight into cellular processes controlling both embryogenesis and stem cell biology. Normalizing quantitative RT-PCR measurements using the geometric mean CT values obtained for the identified mRNAs, offers a reliable method to assess differing patterns of gene expression between the three founding stem cell lineages present within the mammalian preimplantation embryo.

A Tense Situation: Forcing Tumour Progression

DTIC Science & Technology

2009-02-01

Orthopaedic Surgery, University of California at San Francisco, San Francisco, California 94143-0512, USA § Institute for Regenerative Medicine ...growth factor signalling and force from the ECM8,9 (BOX 2). Force and embryogenesis Force has a fundamental role in directing stem cell fate and in...dictating embryonic development10–12. For instance, embryonic stem cells progressively stiffen as cells differentiate13, whereas stem cell shape and

Patent eligibility of stem cells in Europe: where do we stand after 8 years of case law?

PubMed

Storz, Ulrich; Faltus, Timo

2017-01-01

Since 2006, some of the highest ranking European Courts have issued decisions related to the patent eligibility of human embryonic stem cells. The question of patent eligibility of human embryonic stem cells remains, however, still erratic, at least in some aspects. This article will give a short comprehensive overview of the case history, and discuss questions still unsolved.

Identifying Tumor Progenitor Cells | Center for Cancer Research

Cancer.gov

All cells within a tumor are not identical. In fact, only a small subset appears to be capable of actually generating the tumor. These tumor-initiating cells tend to resemble normal stem cells, which have the unique ability to give rise to differentiated cells while simultaneously producing additional undifferentiated stem cells. Most chemotherapeutics affect the bulk of a

Growth and differentiation of embryonic stem cells that lack an intact c-fos gene.

PubMed Central

Field, S J; Johnson, R S; Mortensen, R M; Papaioannou, V E; Spiegelman, B M; Greenberg, M E

1992-01-01

The c-fos protooncogene encodes a transcription factor that is thought to play a critical role in proliferation and differentiation as well as in the physiological response of mature cells to their environment. To test directly the role of c-fos in growth and differentiation, we generated mouse embryonic stem cell lines in which both copies of the c-fos gene were specifically disrupted by homologous recombination. Remarkably, the disruption of both copies of c-fos in these cells has no detectable effect on embryonic stem cell viability, growth rate, or differentiation potential. Embryonic stem cells lacking c-fos can differentiate into a wide range of cell types in tissue culture and also in chimeric mice. We conclude that despite a large body of literature suggesting an important role for c-fos in cell growth and differentiation, in at least some cell types this gene is not essential for these processes. Images PMID:1329091

Rationally optimized cryopreservation of multiple mouse embryonic stem cell lines: I--Comparative fundamental cryobiology of multiple mouse embryonic stem cell lines and the implications for embryonic stem cell cryopreservation protocols.

PubMed

Kashuba, Corinna M; Benson, James D; Critser, John K

2014-04-01

The post-thaw recovery of mouse embryonic stem cells (mESCs) is often assumed to be adequate with current methods. However as this publication will show, this recovery of viable cells actually varies significantly by genetic background. Therefore there is a need to improve the efficiency and reduce the variability of current mESC cryopreservation methods. To address this need, we employed the principles of fundamental cryobiology to improve the cryopreservation protocol of four mESC lines from different genetic backgrounds (BALB/c, CBA, FVB, and 129R1 mESCs) through a comparative study characterizing the membrane permeability characteristics and membrane integrity osmotic tolerance limits of each cell line. In the companion paper, these values were used to predict optimal cryoprotectants, cooling rates, warming rates, and plunge temperatures, and then these predicted optimal protocols were validated against standard freezing protocols. Copyright © 2014 Elsevier Inc. All rights reserved.

[Proliferative capacity of mesenchymal stem cells from human fetal bone marrow and their ability to differentiate into the derivative cell types of three embryonic germ layers].

PubMed

Wang, Yue-Chun; Zhang, Yuan

2008-06-25

Strong proliferative capacity and the ability to differentiate into the derivative cell types of three embryonic germ layers are the two important characteristics of embryonic stem cells. To study whether the mesenchymal stem cells from human fetal bone marrow (hfBM-MSCs) possess these embryonic stem cell-like biological characteristics, hfBM-MSCs were isolated from bone barrows and further purified according to the different adherence of different kinds of cells to the wall of culture flask. The cell cycle of hfBM-MSCs and MSC-specific surface markers such as CD29, CD44, etc were identified using flow cytometry. The expressions of human telomerase reverse transcriptase (hTERT), the embryonic stem cell-specific antigens, such as Oct4 and SSEA-4 were detected with immunocytochemistry at the protein level and were also tested by RT-PCR at the mRNA level. Then, hfBM-MSCs were induced to differentiate toward neuron cells, adipose cells, and islet B cells under certain conditions. It was found that 92.3% passage-4 hfBM-MSCs and 96.1% passage-5 hfBM-MSCs were at G(0)/G(1) phase respectively. hfBM-MSCs expressed CD44, CD106 and adhesion molecule CD29, but not antigens of hematopoietic cells CD34 and CD45, and almost not antigens related to graft-versus-host disease (GVHD), such as HLA-DR, CD40 and CD80. hfBM-MSCs expressed the embryonic stem cell-specific antigens such as Oct4, SSEA-4, and also hTERT. Exposure of these cells to various inductive agents resulted in morphological changes towards neuron-like cells, adipose-like cells, and islet B-like cells and they were tested to be positive for related characteristic markers. These results suggest that there are plenty of MSCs in human fetal bone marrow, and hfBM-MSCs possess the embryonic stem cell-like biological characteristics, moreover, they have a lower immunogenic nature. Thus, hfBM-MSCs provide an ideal source for tissue engineering and cellular therapeutics.

[Regulation of in vitro and in vivo differentiation of mouse embryonic stem cells, embryonic germ cells, and teratocarcinoma cells by TGFb family signaling factors].

PubMed

Gordeeva, O F; Nikonova, T M; Lifantseva, N V

2009-01-01

The activity of specific signaling and transcription factors determines the cell fate in normal development and in tumor transformation. The transcriptional profiles of gene-components of different branches of TGFbeta family signaling pathways were studied in experimental models of initial stages of three-dimensional in vitro differentiation of embryonic stem cells, embryonic germ cells and teratocarcinoma cells and in teratomas and teratocarcinomas developed after their transplantation into immunodeficient Nude mice. Gene profile analysis of studied cell systems have revealed that expression patterns of ActivinA, Nodal, Lefty1, Lefty2, TGF TGFbeta1, BMP4, and GDF were identical in pluripotent stem cells whereas the mRNAs of all examined genes with the exception of Inhibin betaA/ActivinA were detected in the teratocarcinoma cells. These results indicate that differential activity of signaling pathways of the TGFbeta family factors regulates pluripotent state maintenance and pluripotent stem cell differentiation into the progenitors of three germ layers and extraembryonic structures and that normal expression pattern of TGFbeta family factors is rearranged in embryonic teratocarcinoma cells during tumor growth in vitro and in vivo.

Non-Neuronal Release of Gamma-Aminobutyric Acid by Embryonic Pluripotent Stem Cells

PubMed Central

Teng, Lin; Tang, Ya-Bin; Sun, Fan; An, Shi-Min; Zhang, Chun; Yang, Xin-Jie; Lv, Hao-Yu; Lu, Qin; Cui, Yong-Yao; Hu, Jin-Jia

2013-01-01

γ-Aminobutyric acid (GABA), the principle inhibitory transmitter in the mature central nervous system, is also involved in activities outside the nervous system. Recent studies have shown that functional GABA receptors are expressed in embryonic stem (ES) cells and these receptors control ES cell proliferation. However, it is not clear whether ES cells have their own GABAergic transmission output machinery that can fulfill GABA release or whether the cells merely process the GABA receptors by receiving and responding to the diffused GABA released elsewhere. To get further insight into this unresolved problem, we detected the repertoire of components for GABA synthesis, storage, reaction, and termination in ES and embryonal carcinoma stem cells by biological assays, and then directly quantified released GABA in the intercellular milieu from these pluripotent stem (PS) cells by an analytical chemical assay based on high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). We found that embryonic PS cells processed a GABAergic circuit machinery and spontaneously released GABA, which suggests the potential that embryonic PS cells could autonomously establish a GABA niche via release of the transmitter. PMID:23799822

Human embryonic stem cell research: implications from an ethical and legal standpoint.

PubMed

Trepagnier, D M

2000-12-01

The purpose of this paper is to discuss the ethical and legal implications of one of the newest and most controversial medical breakthroughs. Stem cell research has been performed on mice for many years, but human embryonic stem cells are believed by scientists to be the basis for possible treatments and/or cures to many diseases affecting millions of people around the world. In order to perform research on human embryonic stem cells, numerous ethical issues must be addressed. Guidelines and protocols can be established in order to allow scientists to pursue new medical advances while maintaining the highest ethical standards in the use of human embryos. An alternative to using embryos is adult stem cells which have recently proven to be more versatile than previously believed. Opposing views will always be encountered when facing new science technologies. Where should the ethical line be drawn?

Towards a global human embryonic stem cell bank.

PubMed

Lott, Jason P; Savulescu, Julian

2007-08-01

An increasingly unbridgeable gap exists between the supply and demand of transplantable organs. Human embryonic stem cell technology could solve the organ shortage problem by restoring diseased or damaged tissue across a range of common conditions. However, such technology faces several largely ignored immunological challenges in delivering cell lines to large populations. We address some of these challenges and argue in favor of encouraging contribution or intentional creation of embryos from which widely immunocompatible stem cell lines could be derived. Further, we argue that current immunological constraints in tissue transplantation demand the creation of a global stem cell bank, which may hold particular promise for minority populations and other sub-groups currently marginalized from organ procurement and allocation systems. Finally, we conclude by offering a number of practical and ethically oriented recommendations for constructing a human embryonic stem cell bank that we hope will help solve the ongoing organ shortage problem.

The Architectural Organization of Human Stem Cell Cycle Regulatory Machinery

PubMed Central

Stein, Gary S.; Stein, Janet L.; Wijnen, Andre van J; Lian, Jane B.; Montecino, Martin; Medina, Ricardo; Kapinas, Kristie; Ghule, Prachi; Grandy, Rodrigo; Zaidi, Sayyed K.; Becker, Klaus A.

2013-01-01

Two striking features of human embryonic stem cells that support biological activity are an abbreviated cell cycle and reduced complexity to nuclear organization. The potential implications for rapid proliferation of human embryonic stem cells within the context of sustaining pluripotency, suppressing phenotypic gene expression and linkage to simplicity in the architectural compartmentalization of regulatory machinery in nuclear microenvironments is explored. Characterization of the molecular and architectural commitment steps that license human embryonic stem cells to initiate histone gene expression is providing understanding of the principal regulatory mechanisms that control the G1/S phase transition in primitive pluripotent cells. From both fundamental regulatory and clinical perspectives, further understanding of the pluripotent cell cycle in relation to compartmentalization of regulatory machinery in nuclear microenvironments is relevant to applications of stem cells for regenerative medicine and new dimensions to therapy where traditional drug discovery strategies have been minimally effective. PMID:22394165

Priming 3D cultures of human mesenchymal stromal cells toward cartilage formation via developmental pathways.

PubMed

Centola, Matteo; Tonnarelli, Beatrice; Schären, Stefan; Glaser, Nicolas; Barbero, Andrea; Martin, Ivan

2013-11-01

The field of regenerative medicine has increasingly recognized the importance to be inspired by developmental processes to identify signaling pathways crucial for 3D organogenesis and tissue regeneration. Here, we aimed at recapitulating the first events occurring during limb development (ie, cell condensation and expansion of an undifferentiated mesenchymal cell population) to prime 3D cultures of human bone marrow-derived mesenchymal stromal/stem cells (hBM-MSC) toward the chondrogenic route. Based on embryonic development studies, we hypothesized that Wnt3a and fibroblast growth factor 2 (FGF2) induce hBM-MSC to proliferate in 3D culture as an undifferentiated pool of progenitors (defined by clonogenic capacity and expression of typical markers), retaining chondrogenic potential upon induction by suitable morphogens. hBM-MSC were responsive to Wnt signaling in 3D pellet culture, as assessed by significant upregulation of main target genes and increase of unphosphorylated β-catenin levels. Wnt3a was able to induce a five-fold increase in the number of proliferating hBM-MSC (6.4% vs. 1.3% in the vehicle condition), although total DNA content of the 3D construct was decreasing over time. Preconditioning with Wnt3a improved transforming growth factor-β1 mediated chondrogenesis (30% more glycosaminoglycans/cell in average). In contrast to developmental and 2D MSC culture models, FGF2 antagonized the Wnt-mediated effects. Interestingly, the CD146⁺ subpopulation was found to be more responsive to Wnt3a. The presented data indicate a possible strategy to prime 3D cultures of hBM-MSC by invoking a "developmental engineering" approach. The study also identifies some opportunities and challenges to cross-fertilize skeletal development models and 3D hBM-MSC culture systems.

Myosin Heavy Chain Gene Expression in Developing Neonatal Skeletal Muscle: Involvement of the Nerve, Gravity, and Thyroid State

NASA Technical Reports Server (NTRS)

Baldwin, K. M.; Adams, G.; Haddad, F.; Zeng, M.; Qin, A.; Qin, L.; McCue, S.; Bodell, P.

1999-01-01

The myosin heavy chain (MHC) gene family encodes at least six MHC proteins (herein designated as neonatal, embryonic, slow type I (beta), and fast IIa, IIx, and IIb) that are expressed in skeletal muscle in a muscle-specific and developmentally-regulated fashion. At birth, both antigravity (e.g. soleus) and locomotor (e.g., plantaris) skeletal muscles are undifferentiated relative to the adult MHC phenotype such that the neonatal and embryonic MHC isoforms account for 80 - 90% of the MHC pool in a fast locomotor muscle; whereas, the embryonic and slow, type I isoforms account for approx. 90% of the pool in a typical antigravity muscle. The goal of this study was to investigate the role of an intact nerve, gravity and thyroid hormone (T3), as well as certain interactions of these interventions, on MHC gene expression in developing neonatal skeletal muscles of rodents.

Ethanol Inactivated Mouse Embryonic Fibroblasts Maintain the Self-Renew and Proliferation of Human Embryonic Stem Cells.

PubMed

Huang, Boxian; Ning, Song; Zhuang, Lili; Jiang, Chunyan; Cui, Yugui; Fan, Guoping; Qin, Lianju; Liu, Jiayin

2015-01-01

Conventionally, mouse embryonic fibroblasts (MEFs) inactivated by mitomycin C or irradiation were applied to support the self-renew and proliferation of human embryonic stem cells (hESCs). To avoid the disadvangtages of mitomycin C and irradiation, here MEFs were treated by ethanol (ET). Our data showed that 10% ET-inactivated MEFs (eiMEFs) could well maintain the self-renew and proliferation of hESCs. hESCs grown on eiMEFs expressed stem cell markers of NANOG, octamer-binding protein 4 (OCT4), stage-specific embryonic antigen-4 (SSEA4) and tumour related antigen-1-81 (TRA-1-81), meanwhile maintained normal karyotype after long time culture. Also, hESCs cocultured with eiMEFs were able to form embryoid body (EB) in vitro and develop teratoma in vivo. Moreover, eiMEFs could keep their nutrient functions after long time cryopreservation. Our results indicate that the application of eiMEF in hESCs culture is safe, economical and convenient, thus is a better choice.

Lineage-specific enhancers activate self-renewal genes in macrophages and embryonic stem cells

PubMed Central

Soucie, Erinn L.; Weng, Ziming; Geirsdóttir, Laufey; Molawi, Kaaweh; Maurizio, Julien; Fenouil, Romain; Mossadegh-Keller, Noushine; Gimenez, Gregory; VanHille, Laurent; Beniazza, Meryam; Favret, Jeremy; Berruyer, Carole; Perrin, Pierre; Hacohen, Nir; Andrau, J.-C.; Ferrier, Pierre; Dubreuil, Patrice; Sidow, Arend; Sieweke, Michael H.

2016-01-01

Differentiated macrophages can self-renew in tissues and expand long-term in culture, but the gene regulatory mechanisms that accomplish self-renewal in the differentiated state have remained unknown. Here we show that in mice, the transcription factors MafB and c-Maf repress a macrophage-specific enhancer repertoire associated with a gene network controlling self-renewal. Single cell analysis revealed that, in vivo, proliferating resident macrophages can access this network by transient down-regulation of Maf transcription factors. The network also controls embryonic stem cell self-renewal but is associated with distinct embryonic stem cell-specific enhancers. This indicates that distinct lineage-specific enhancer platforms regulate a shared network of genes that control self-renewal potential in both stem and mature cells. PMID:26797145

Ethical questions to ponder in the European stem cell patent debate.

PubMed

Curley, Duncan; Sharples, Andrew

2006-01-01

Patents may be refused in Europe on ethical grounds. Whereas in the past this issue has arisen only infrequently, recent developments in human embryonic stem cell research have given rise to conflicting opinions in Europe as to the approach that should be adopted in relation to patents. The United Kingdom Patent Office has adopted a positive policy towards inventions involving human embryonic stem cells, but the European Patent Office has to date refused to grant patent applications involving similar subject-matter. A series of legal questions on the role of ethics in granting European patents is now to be considered for clarification by the European Patent Office. The answers to these questions should eventually resolve the debate on the patenting of human embryonic stem cells throughout Europe.

[Embryonic stem cells - a scientific by-product of the assisted reproduction technology?].

PubMed

Sterthaus, Oliver; Zhang, Hong; De Geyter, Christian

2009-12-01

The differentiation potential of embryonic stem (ES) cells seems to be higher when compared to adult stem cells, which mainly differentiate into certain tissue types only. ES cells have the potential to play an important role in regenerative medicine as demonstrated with murine ES cells. However, with human embryonic stem cells (hESC) several obstacles still have to be overcome, when these are to be used in clinical applications. The expansion of hESC, safety issues as well as the immune-tolerance after transplantation are all problems that still have to be solved. Since 2005 the derivation of hESC lines from super-numerous embryos has become permitted in Switzerland, albeit under strictly restrictive guidelines. In 2008 the Basler hESC laboratory was successful in derivating the first hESC line with a normal chromosome complement in Switzerland (CHES2). Now, new applications allow the personalized establishment of immune-tolerant stem cells, which lead to the replacement of therapeutic cloning by induced pluripotent stem cells (iPS).

Generation of stomach tissue from mouse embryonic stem cells.

PubMed

Noguchi, Taka-aki K; Ninomiya, Naoto; Sekine, Mari; Komazaki, Shinji; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

2015-08-01

Successful pluripotent stem cell differentiation methods have been developed for several endoderm-derived cells, including hepatocytes, β-cells and intestinal cells. However, stomach lineage commitment from pluripotent stem cells has remained a challenge, and only antrum specification has been demonstrated. We established a method for stomach differentiation from embryonic stem cells by inducing mesenchymal Barx1, an essential gene for in vivo stomach specification from gut endoderm. Barx1-inducing culture conditions generated stomach primordium-like spheroids, which differentiated into mature stomach tissue cells in both the corpus and antrum by three-dimensional culture. This embryonic stem cell-derived stomach tissue (e-ST) shared a similar gene expression profile with adult stomach, and secreted pepsinogen as well as gastric acid. Furthermore, TGFA overexpression in e-ST caused hypertrophic mucus and gastric anacidity, which mimicked Ménétrier disease in vitro. Thus, in vitro stomach tissue derived from pluripotent stem cells mimics in vivo development and can be used for stomach disease models.

An Overview of Direct Somatic Reprogramming: The Ins and Outs of iPSCs

PubMed Central

Menon, Siddharth; Shailendra, Siny; Renda, Andrea; Longaker, Michael; Quarto, Natalina

2016-01-01

Stem cells are classified into embryonic stem cells and adult stem cells. An evolving alternative to conventional stem cell therapies is induced pluripotent stem cells (iPSCs), which have a multi-lineage potential comparable to conventionally acquired embryonic stem cells with the additional benefits of being less immunoreactive and avoiding many of the ethical concerns raised with the use of embryonic material. The ability to generate iPSCs from somatic cells provides tremendous promise for regenerative medicine. The breakthrough of iPSCs has raised the possibility that patient-specific iPSCs can provide autologous cells for cell therapy without the concern for immune rejection. iPSCs are also relevant tools for modeling human diseases and drugs screening. However, there are still several hurdles to overcome before iPSCs can be used for translational purposes. Here, we review the recent advances in somatic reprogramming and the challenges that must be overcome to move this strategy closer to clinical application. PMID:26805822

Cardiac Progenitor Cells and Bone Marrow-Derived Very Small Embryonic-Like Stem Cells for Cardiac Repair After Myocardial Infarction

PubMed Central

Tang, Xian-Liang; Rokosh, D. Gregg; Guo, Yiru; Bolli, Roberto

2010-01-01

Heart failure after myocardial infarction (MI) continues to be the most prevalent cause of morbidity and mortality worldwide. Although pharmaceutical agents and interventional strategies have contributed greatly to therapy, new and superior treatment modalities are urgently needed given the overall disease burden. Stem cell-based therapy is potentially a promising strategy to lead to cardiac repair after MI. An array of cell types has been explored in this respect, including skeletal myoblasts, bone marrow (BM)-derived stem cells, embryonic stem cells, and more recently, cardiac progenitor cells (CPCs). Recently studies have obtained evidence that transplantation of CPCs or BM-derived very small embryonic-like stem cells can improve cardiac function and alleviate cardiac remodeling, supporting the potential therapeutic utility of these cells for cardiac repair. This report summarizes the current data from those studies and discusses the potential implication of these cells in developing clinically-relevant stem cell-based therapeutic strategies for cardiac regeneration. PMID:20081317

Derivation of Pluripotent Stem Cells with In Vivo Embryonic and Extraembryonic Potency.

PubMed

Yang, Yang; Liu, Bei; Xu, Jun; Wang, Jinlin; Wu, Jun; Shi, Cheng; Xu, Yaxing; Dong, Jiebin; Wang, Chengyan; Lai, Weifeng; Zhu, Jialiang; Xiong, Liang; Zhu, Dicong; Li, Xiang; Yang, Weifeng; Yamauchi, Takayoshi; Sugawara, Atsushi; Li, Zhongwei; Sun, Fangyuan; Li, Xiangyun; Li, Chen; He, Aibin; Du, Yaqin; Wang, Ting; Zhao, Chaoran; Li, Haibo; Chi, Xiaochun; Zhang, Hongquan; Liu, Yifang; Li, Cheng; Duo, Shuguang; Yin, Ming; Shen, Huan; Belmonte, Juan Carlos Izpisua; Deng, Hongkui

2017-04-06

Of all known cultured stem cell types, pluripotent stem cells (PSCs) sit atop the landscape of developmental potency and are characterized by their ability to generate all cell types of an adult organism. However, PSCs show limited contribution to the extraembryonic placental tissues in vivo. Here, we show that a chemical cocktail enables the derivation of stem cells with unique functional and molecular features from mice and humans, designated as extended pluripotent stem (EPS) cells, which are capable of chimerizing both embryonic and extraembryonic tissues. Notably, a single mouse EPS cell shows widespread chimeric contribution to both embryonic and extraembryonic lineages in vivo and permits generating single-EPS-cell-derived mice by tetraploid complementation. Furthermore, human EPS cells exhibit interspecies chimeric competency in mouse conceptuses. Our findings constitute a first step toward capturing pluripotent stem cells with extraembryonic developmental potentials in culture and open new avenues for basic and translational research. VIDEO ABSTRACT. Copyright © 2017 Elsevier Inc. All rights reserved.

[Research with human embryo stem cells. Foundations and judicial limits].

PubMed

Eser, Albin; Koch, Hans-Georg

2004-01-01

Research with human embryos, and particularly, the use for scientific purposes of human embryonic stem cells has given raise to different sort of problems at the international level. One of the most strict regulation in this field, is this lecture Professors Albin Eser and Hans-Georg Koch analyse the german legal framework in relation with the use of embryos and human embryonic stem cells for scientific purposes.

Inhibition of Embryonic Genes to Control Colorectal Cancer Metastasis

DTIC Science & Technology

2014-09-01

14. ABSTRACT Embryonic core transcription factors (TFs), primarily the retrogene NanogP8, are the master regulators of cancer stem cells (CSC) in...core transcription factors (TFs), primarily the retrogene NanogP8, are the master regulators of cancer stem cells (CSC) in human colorectal carcinoma...maintaining the stemness of colorectal carcinoma (CRC) as well as the identification of two different pathways by which NANOG and NANOGP8 control pluripotency

Developments in stem cell research and therapeutic cloning: Islamic ethical positions, a review.

PubMed

Fadel, Hossam E

2012-03-01

Stem cell research is very promising. The use of human embryos has been confronted with objections based on ethical and religious positions. The recent production of reprogrammed adult (induced pluripotent) cells does not - in the opinion of scientists - reduce the need to continue human embryonic stem cell research. So the debate continues. Islam always encouraged scientific research, particularly research directed toward finding cures for human disease. Based on the expectation of potential benefits, Islamic teachings permit and support human embryonic stem cell research. The majority of Muslim scholars also support therapeutic cloning. This permissibility is conditional on the use of supernumerary early pre-embryos which are obtained during infertility treatment in vitro fertilization (IVF) clinics. The early pre-embryos are considered in Islamic jurisprudence as worthy of respect but do not have the full sanctity offered to the embryo after implantation in the uterus and especially after ensoulment. In this paper the Islamic positions regarding human embryonic stem cell research and therapeutic cloning are reviewed in some detail, whereas positions in other religious traditions are mentioned only briefly. The status of human embryonic stem cell research and therapeutic cloning in different countries, including the USA and especially in Muslim countries, is discussed. © 2010 Blackwell Publishing Ltd.

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

PubMed Central

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

Pipette-based Method to Study Embryoid Body Formation Derived from Mouse and Human Pluripotent Stem Cells Partially Recapitulating Early Embryonic Development Under Simulated Microgravity Conditions

NASA Astrophysics Data System (ADS)

Shinde, Vaibhav; Brungs, Sonja; Hescheler, Jürgen; Hemmersbach, Ruth; Sachinidis, Agapios

2016-06-01

The in vitro differentiation of pluripotent stem cells partially recapitulates early in vivo embryonic development. More recently, embryonic development under the influence of microgravity has become a primary focus of space life sciences. In order to integrate the technique of pluripotent stem cell differentiation with simulated microgravity approaches, the 2-D clinostat compatible pipette-based method was experimentally investigated and adapted for investigating stem cell differentiation processes under simulated microgravity conditions. In order to keep residual accelerations as low as possible during clinorotation, while also guaranteeing enough material for further analysis, stem cells were exposed in 1-mL pipettes with a diameter of 3.5 mm. The differentiation of mouse and human pluripotent stem cells inside the pipettes resulted in the formation of embryoid bodies at normal gravity (1 g) after 24 h and 3 days. Differentiation of the mouse pluripotent stem cells on a 2-D pipette-clinostat for 3 days also resulted in the formation of embryoid bodies. Interestingly, the expression of myosin heavy chain was downregulated when cultivation was continued for an additional 7 days at normal gravity. This paper describes the techniques for culturing and differentiation of pluripotent stem cells and exposure to simulated microgravity during culturing or differentiation on a 2-D pipette clinostat. The implementation of these methodologies along with -omics technologies will contribute to understand the mechanisms regulating how microgravity influences early embryonic development.

Neural Stem Cells Derived Directly from Adipose Tissue.

PubMed

Petersen, Eric D; Zenchak, Jessica R; Lossia, Olivia V; Hochgeschwender, Ute

2018-05-01

Neural stem cells (NSCs) are characterized as self-renewing cell populations with the ability to differentiate into the multiple tissue types of the central nervous system. These cells can differentiate into mature neurons, astrocytes, and oligodendrocytes. This category of stem cells has been shown to be a promisingly effective treatment for neurodegenerative diseases and neuronal injury. Most treatment studies with NSCs in animal models use embryonic brain-derived NSCs. This approach presents both ethical and feasibility issues for translation to human patients. Adult tissue is a more practical source of stem cells for transplantation therapies in humans. Some adult tissues such as adipose tissue and bone marrow contain a wide variety of stem cell populations, some of which have been shown to be similar to embryonic stem cells, possessing many pluripotent properties. Of these stem cell populations, some are able to respond to neuronal growth factors and can be expanded in vitro, forming neurospheres analogous to cells harvested from embryonic brain tissue. In this study, we describe a method for the collection and culture of cells from adipose tissue that directly, without going through intermediates such as mesenchymal stem cells, results in a population of NSCs that are able to be expanded in vitro and be differentiated into functional neuronal cells. These adipose-derived NSCs display a similar phenotype to those directly derived from embryonic brain. When differentiated into neurons, cells derived from adipose tissue have spontaneous spiking activity with network characteristics similar to that of neuronal cultures.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whittaker, Peter A.

A brief outline of stem cells, stem cell therapy and therapeutic cloning is given. The position of therapeutic cloning with regard to other embryonic manipulations - IVF-based reproduction, embryonic stem formation from IVF embryos and reproductive cloning - is indicated. The main ethically challenging stages in therapeutic cloning are considered to be the nuclear transfer process including the source of eggs for this and the destruction of an embryo to provide stem cells for therapeutic use. The extremely polarised nature of the debate regarding the status of an early human embryo is noted, and some potential alternative strategies for preparingmore » immunocompatible pluripotent stem cells are indicated.« less

Markers of murine embryonic and neural stem cells, neurons and astrocytes: reference points for developmental neurotoxicity testing

EPA Science Inventory

Developmental neurotoxicity (DNT) is a significant concern for environmental chemicals, as well as for food and drug constituents. The sensitivity of animal-based DNT models is unclear, and they are expensive and time consuming. Murine embryonic stem cells (mESC) recapitulate sev...

REDOX DISRUPTING POTENTIAL OF TOXCAST CHEMICALS RANKED BY ACTIVITY IN MOUSE EMBRYONIC STEM CELLS

EPA Science Inventory

To gain insight regarding the adverse outcome pathways leading to developmental toxicity following exposure to chemicals, we evaluated ToxCast™ Phase I chemicals in an adherent mouse embryonic stem cell (mESC) assay and identified a redox sensitive pathway that correlated with al...

Redox Disrupting Potential of ToxCast™Chemicals Ranked by Activity in Mouse Embryonic Stem Cells

EPA Science Inventory

Little is known regarding the adverse outcome pathways responsible for developmental toxicity following exposure to chemicals. An evaluation of Toxoast™ Phase I chemicals in an adherent mouse embryonic stem cell (mESC) assay revealed a redox sensitive pathway that correlated with...

Assessment of a 42 metal salts chemical library in mouse embryonic stem cells

EPA Science Inventory

The developmental effects of xenobiotics on differentiation can be profiled using mouse embryonic stem cells (mESCs). The adherent cell differentiation and cytotoxicity (ACDC) technique was used to evaluate a library of 42 metal and metaloid salts. Jl mESCs were allowed to prolif...

Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells.

EPA Science Inventory

Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells S. Hunter, M. Rosen, M. Hoopes, H. Nichols, S. Jeffay, K. Chandler1, Integrated Systems Toxicology Division, National Health and Environmental Effects Research Labor...

Transplantation of neurons derived from human iPS cells cultured on collagen matrix into guinea-pig cochleae.

PubMed

Ishikawa, Masaaki; Ohnishi, Hiroe; Skerleva, Desislava; Sakamoto, Tatsunori; Yamamoto, Norio; Hotta, Akitsu; Ito, Juichi; Nakagawa, Takayuki

2017-06-01

The present study examined the efficacy of a neural induction method for human induced pluripotent stem (iPS) cells to eliminate undifferentiated cells and to determine the feasibility of transplanting neurally induced cells into guinea-pig cochleae for replacement of spiral ganglion neurons (SGNs). A stepwise method for differentiation of human iPS cells into neurons was used. First, a neural induction method was established on Matrigel-coated plates; characteristics of cell populations at each differentiation step were assessed. Second, neural stem cells were differentiated into neurons on a three-dimensional (3D) collagen matrix, using the same protocol of culture on Matrigel-coated plates; neuron subtypes in differentiated cells on a 3D collagen matrix were examined. Then, human iPS cell-derived neurons cultured on a 3D collagen matrix were transplanted into intact guinea-pig cochleae, followed by histological analysis. In vitro analyses revealed successful induction of neural stem cells from human iPS cells, with no retention of undifferentiated cells expressing OCT3/4. After the neural differentiation of neural stem cells, approximately 70% of cells expressed a neuronal marker, 90% of which were positive for vesicular glutamate transporter 1 (VGLUT1). The expression pattern of neuron subtypes in differentiated cells on a 3D collagen matrix was identical to that of the differentiated cells on Matrigel-coated plates. In addition, the survival of transplant-derived neurons was achieved when inflammatory responses were appropriately controlled. Our preparation method for human iPS cell-derived neurons efficiently eliminated undifferentiated cells and contributed to the settlement of transplant-derived neurons expressing VGLUT1 in guinea-pig cochleae. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

ESCAPE: database for integrating high-content published data collected from human and mouse embryonic stem cells.

PubMed

Xu, Huilei; Baroukh, Caroline; Dannenfelser, Ruth; Chen, Edward Y; Tan, Christopher M; Kou, Yan; Kim, Yujin E; Lemischka, Ihor R; Ma'ayan, Avi

2013-01-01

High content studies that profile mouse and human embryonic stem cells (m/hESCs) using various genome-wide technologies such as transcriptomics and proteomics are constantly being published. However, efforts to integrate such data to obtain a global view of the molecular circuitry in m/hESCs are lagging behind. Here, we present an m/hESC-centered database called Embryonic Stem Cell Atlas from Pluripotency Evidence integrating data from many recent diverse high-throughput studies including chromatin immunoprecipitation followed by deep sequencing, genome-wide inhibitory RNA screens, gene expression microarrays or RNA-seq after knockdown (KD) or overexpression of critical factors, immunoprecipitation followed by mass spectrometry proteomics and phosphoproteomics. The database provides web-based interactive search and visualization tools that can be used to build subnetworks and to identify known and novel regulatory interactions across various regulatory layers. The web-interface also includes tools to predict the effects of combinatorial KDs by additive effects controlled by sliders, or through simulation software implemented in MATLAB. Overall, the Embryonic Stem Cell Atlas from Pluripotency Evidence database is a comprehensive resource for the stem cell systems biology community. Database URL: http://www.maayanlab.net/ESCAPE

Loss of EGFR-ASAP1 signaling in metastatic and unresectable hepatoblastoma.

PubMed

Ranganathan, Sarangarajan; Ningappa, Mylarappa; Ashokkumar, Chethan; Higgs, Brandon W; Min, Jun; Sun, Qing; Schmitt, Lori; Subramaniam, Shankar; Hakonarson, Hakon; Sindhi, Rakesh

2016-12-02

Hepatoblastoma (HBL), the most common childhood liver cancer is cured with surgical resection after chemotherapy or with liver transplantation if local invasion and multifocality preclude resection. However, variable survival rates of 60-80% and debilitating chemotherapy sequelae argue for more informed treatment selection, which is not possible by grading the Wnt-β-catenin over activity present in most HBL tumors. A hypothesis-generating whole transcriptome analysis shows that HBL tumors removed at transplantation are enriched most for cancer signaling pathways which depend predominantly on epidermal growth factor (EGF) signaling, and to a lesser extent, on aberrant Wnt-β-catenin signaling. We therefore evaluated whether EGFR, ASAP1, ERBB2 and ERBB4, which signal downstream after ligation of EGF, and which show aberrant expression in several other invasive cancers, would also predict HBL tumor invasiveness. Immunohistochemistry of HBL tumors (n = 60), which are histologically heterogeneous, shows that compared with well-differentiated fetal cells, less differentiated embryonal and undifferentiated small cells (SCU) progressively lose EGFR and ASAP1 expression. This trend is exaggerated in unresectable, locally invasive or metastatic tumors, in which embryonal tumor cells are EGFR-negative, while SCU cells are EGFR-negative and ASAP1-negative. Loss of EGFR-ASAP1 signaling characterizes undifferentiated and invasive HBL. EGFR-expressing HBL tumors present novel therapeutic targeting opportunities.

Characteristics and outcomes in children with undifferentiated embryonal sarcoma of the liver: A report from the National Cancer Database.

PubMed

Shi, Yan; Rojas, Yesenia; Zhang, Wei; Beierle, Elizabeth A; Doski, John J; Goldfarb, Melanie; Goldin, Adam B; Gow, Kenneth W; Langer, Monica; Meyers, Rebecka L; Nuchtern, Jed G; Vasudevan, Sanjeev A

2017-04-01

To examine patient characteristics and outcomes in children with undifferentiated embryonal sarcoma of the liver (UESL) using a multi-institutional database. UESL is a rare disease (incidence is one per million). Therefore, the current literature is mostly limited to small case series. The National Cancer Database was queried for primary UESL diagnosed between 1998 and 2012. A total of 103 patients (<18 years) were identified. The 5-year overall survival of the entire group was 86%. The best outcomes were seen in children who had tumors smaller than 15 cm and were able to undergo surgical resection with or without chemotherapy. Margin status did not appear to significantly affect survival. The most common type of resection was hemihepatectomy (37%), followed by sectionectomy (10%) and trisectionectomy (10%). Orthotopic liver transplant was performed in 10 children, all of whom survived to 5 years. Surgical resection with or without chemotherapy should be the mainstay of treatment in children with UESL, and is associated with very favorable outcomes. Negative surgical margins were not associated with improved survival. Orthotopic liver transplantation may be a viable method of attaining local control in tumors, which would otherwise be unresectable. © 2016 The Authors. Pediatric Blood & Cancer Published by Wiley Periodicals, Inc.

Characteristics and outcomes in children with undifferentiated embryonal sarcoma of the liver: A report from the National Cancer Database

PubMed Central

Shi, Yan; Rojas, Yesenia; Zhang, Wei; Beierle, Elizabeth A.; Doski, John J.; Goldfarb, Melanie; Goldin, Adam B.; Gow, Kenneth W.; Langer, Monica; Meyers, Rebecka L.; Nuchtern, Jed G.

2016-01-01

Abstract Objective To examine patient characteristics and outcomes in children with undifferentiated embryonal sarcoma of the liver (UESL) using a multi‐institutional database. Summary Background Data UESL is a rare disease (incidence is one per million). Therefore, the current literature is mostly limited to small case series. Methods The National Cancer Database was queried for primary UESL diagnosed between 1998 and 2012. Results A total of 103 patients (<18 years) were identified. The 5‐year overall survival of the entire group was 86%. The best outcomes were seen in children who had tumors smaller than 15 cm and were able to undergo surgical resection with or without chemotherapy. Margin status did not appear to significantly affect survival. The most common type of resection was hemihepatectomy (37%), followed by sectionectomy (10%) and trisectionectomy (10%). Orthotopic liver transplant was performed in 10 children, all of whom survived to 5 years. Conclusion Surgical resection with or without chemotherapy should be the mainstay of treatment in children with UESL, and is associated with very favorable outcomes. Negative surgical margins were not associated with improved survival. Orthotopic liver transplantation may be a viable method of attaining local control in tumors, which would otherwise be unresectable. PMID:27781381

Isolation and gene expression analysis of single potential human spermatogonial stem cells.

PubMed

von Kopylow, K; Schulze, W; Salzbrunn, A; Spiess, A-N

2016-04-01

It is possible to isolate pure populations of single potential human spermatogonial stem cells without somatic contamination for down-stream applications, for example cell culture and gene expression analysis. We isolated pure populations of single potential human spermatogonial stem cells (hSSC) without contaminating somatic cells and analyzed gene expression of these cells via single-cell real-time RT-PCR. The isolation of a pure hSSC fraction could enable clinical applications such as fertility preservation for prepubertal boys and in vitro-spermatogenesis. By utilizing largely nonspecific markers for the isolation of spermatogonia (SPG) and hSSC, previously published cell selection methods are not able to deliver pure target cell populations without contamination by testicular somatic cells. However, uniform cell populations free of somatic cells are necessary to guarantee defined growth conditions in cell culture experiments and to prevent unintended stem cell differentiation. Fibroblast growth factor receptor 3 (FGFR3) is a cell surface protein of human undifferentiated A-type SPG and a promising candidate marker for hSSC. It is exclusively expressed in small, non-proliferating subgroups of this spermatogonial cell type together with the pluripotency-associated protein and spermatogonial nuclear marker undifferentiated embryonic cell transcription factor 1 (UTF1). We specifically selected the FGFR3-positive spermatogonial subpopulation from two 30 mg biopsies per patient from a total of 37 patients with full spermatogenesis and three patients with meiotic arrest. We then employed cell selection with magnetic beads in combination with a fluorescence-activated cell sorter antibody directed against human FGFR3 to tag and visually identify human FGFR3-positive spermatogonia. Positively selected and bead-labeled cells were subsequently picked with a micromanipulator. Analysis of the isolated cells was carried out by single-cell real-time RT-PCR, real-time RT-PCR, immunocytochemistry and live/dead staining. Single-cell real-time RT-PCR and real-time RT-PCR of pooled cells indicate that bead-labeled single cells express FGFR3 with high heterogeneity at the mRNA level, while bead-unlabeled cells lack FGFR3 mRNA. Furthermore, isolated cells exhibit strong immunocytochemical staining for the stem cell factor UTF1 and are viable. The cell population isolated in this study has to be tested for their potential stem cell characteristics via xenotransplantation. Due to the small amount of the isolated cells, propagation by cell culture will be essential. Other potential hSSC without FGFR3 surface expression will not be captured with the provided experimental design. The technical approach as developed in this work could encourage the scientific community to test other established or novel hSSC markers on single SPG that present with potential stem cell-like features. The project was funded by the DFG Research Unit FOR1041 Germ cell potential (SCH 587/3-2) and DFG grants to K.v.K. (KO 4769/2-1) and A.-N.S. (SP 721/4-1). The authors declare no competing interests. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

High-throughput identification of small molecules that affect human embryonic vascular development

PubMed Central

Vazão, Helena; Rosa, Susana; Barata, Tânia; Costa, Ricardo; Pitrez, Patrícia R.; Honório, Inês; de Vries, Margreet R.; Papatsenko, Dimitri; Benedito, Rui; Saris, Daniel; Khademhosseini, Ali; Quax, Paul H. A.; Pereira, Carlos F.; Mercader, Nadia; Ferreira, Lino

2017-01-01

Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach yields low-throughput and limited mechanistic information regarding the biological pathways and potential adverse consequences in humans. To develop a screening platform for molecules that affect human embryonic development based on endothelial cells (ECs) derived from human pluripotent stem cells, we differentiated human pluripotent stem cells into embryonic ECs and induced their maturation under arterial flow conditions. These cells were then used to screen compounds that specifically affect embryonic vasculature. Using this platform, we have identified two compounds that have higher inhibitory effect in embryonic than postnatal ECs. One of them was fluphenazine (an antipsychotic), which inhibits calmodulin kinase II. The other compound was pyrrolopyrimidine (an antiinflammatory agent), which inhibits vascular endothelial growth factor receptor 2 (VEGFR2), decreases EC viability, induces an inflammatory response, and disrupts preformed vascular networks. The vascular effect of the pyrrolopyrimidine was further validated in prenatal vs. adult mouse ECs and in embryonic and adult zebrafish. We developed a platform based on human pluripotent stem cell-derived ECs for drug screening, which may open new avenues of research for the study and modulation of embryonic vasculature. PMID:28348206

High-throughput identification of small molecules that affect human embryonic vascular development.

PubMed

Vazão, Helena; Rosa, Susana; Barata, Tânia; Costa, Ricardo; Pitrez, Patrícia R; Honório, Inês; de Vries, Margreet R; Papatsenko, Dimitri; Benedito, Rui; Saris, Daniel; Khademhosseini, Ali; Quax, Paul H A; Pereira, Carlos F; Mercader, Nadia; Fernandes, Hugo; Ferreira, Lino

2017-04-11

Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach yields low-throughput and limited mechanistic information regarding the biological pathways and potential adverse consequences in humans. To develop a screening platform for molecules that affect human embryonic development based on endothelial cells (ECs) derived from human pluripotent stem cells, we differentiated human pluripotent stem cells into embryonic ECs and induced their maturation under arterial flow conditions. These cells were then used to screen compounds that specifically affect embryonic vasculature. Using this platform, we have identified two compounds that have higher inhibitory effect in embryonic than postnatal ECs. One of them was fluphenazine (an antipsychotic), which inhibits calmodulin kinase II. The other compound was pyrrolopyrimidine (an antiinflammatory agent), which inhibits vascular endothelial growth factor receptor 2 (VEGFR2), decreases EC viability, induces an inflammatory response, and disrupts preformed vascular networks. The vascular effect of the pyrrolopyrimidine was further validated in prenatal vs. adult mouse ECs and in embryonic and adult zebrafish. We developed a platform based on human pluripotent stem cell-derived ECs for drug screening, which may open new avenues of research for the study and modulation of embryonic vasculature.

Stem Cells

MedlinePlus

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

Repression of mammosphere formation of human breast cancer cells by soy isoflavone genistein and blueberry polyphenolic acids suggests diet-mediated targeting of cancer stem-like/progenitor cells

USDA-ARS?s Scientific Manuscript database

Mammary stem cells are undifferentiated epithelial cells which initiate mammary tumors and render them resistant to anticancer therapies, when deregulated. Diets rich in fruits and vegetables are implicated in breast cancer risk reduction, yet underlying mechanisms are poorly understood. Here, we ad...

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

PubMed

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.

Informing Stem Cell-Based Tendon Tissue Engineering Approaches with Embryonic Tendon Development.

PubMed

Okech, William; Kuo, Catherine K

Adult tendons fail to regenerate normal tissue after injury, and instead form dysfunctional scar tissue with abnormal mechanical properties. Surgical repair with grafts is the current standard to treat injuries, but faces significant limitations including pain and high rates of re-injury. To address this, we aim to regenerate new, normal tendons to replace dysfunctional tendons. A common approach to tendon tissue engineering is to design scaffolds and bioreactors based on adult tendon properties that can direct adult stem cell tenogenesis. Despite significant progress, advances have been limited due, in part, to a need for markers and potent induction cues. Our goal is to develop novel tendon tissue engineering approaches informed by embryonic tendon development. We are characterizing structure-property relationships of embryonic tendon to identify design parameters for three-dimensional scaffolds and bioreactor mechanical loading systems to direct adult stem cell tenogenesis. We will review studies in which we quantified changes in the mechanical and biochemical properties of tendon during embryonic development and elucidated specific mechanisms of functional property elaboration. We then examined the effects of these mechanical and biochemical factors on embryonic tendon cell behavior. Using custom-designed bioreactors, we also examined the effects of dynamic mechanical loading and growth factor treatment on embryonic tendon cells. Our findings have established cues to induce tenogenesis as well as metrics to evaluate differentiation. We finish by discussing how we have evaluated the tenogenic differentiation potential of adult stem cells by comparing their responses to that of embryonic tendon cells in these culture systems.

Effect of allo- and xenotransplantation of embryonic nervous tissue and umbilical cord blood-derived stem cells on structural and functional state of cerebral cortex of albino rats in posttraumatic period.

PubMed

Ereniev, S I; Semchenko, V V; Sysheva, E V; Bogdashin, I V; Shapovalova, V V; Khizhnyak, A S; Gasanenko, L N

2005-11-01

Comparative study of the structural and functional state of cerebral cortex of adult albino rats after intracerebral allo- and xenotransplantation of embryonic nervous tissue and intravenous injection of umbilical cord blood-derived stem cells at different terms after diffuse-focal cerebral trauma revealed the best cerebroprotective effect on day 7 of posttraumatic period in animals receiving embryonic nervous tissue.

Fluorescence lifetime imaging of induced pluripotent stem cells

NASA Astrophysics Data System (ADS)

Uchugonova, Aisada; Batista, Ana; König, Karsten

2014-02-01

The multiphoton FLIM tomograph MPTflex with its flexible scan head, articulated arm, and the tunable femtosecond laser source was employed to study cell monolayers and 3D cell clusters. FLIM was performed with 250 ps temporal resolution and submicron special resolution using time-correlated single photon counting. The autofluorescence based on NAD(P)H and flavins/flavoproteins has been measured in mouse embryonic fibroblasts, induced pluripotent stem cells (iPS cells) originated from mouse embryonic fibroblasts and non-proliferative mouse embryonic fibroblasts.

3D Graphene Oxide-encapsulated Gold Nanoparticles to Detect Neural Stem Cell Differentiation

PubMed Central

Kim, Tae-Hyung; Lee, Ki-Bum; Choi, Jeong-Woo

2013-01-01

Monitoring of stem cell differentiation and pluripotency is an important step for the practical use of stem cells in the field of regenerative medicine. Hence, a new non-destructive detection tool capable of in situ monitoring of stem cell differentiation is highly needed. In this study, we report a 3D graphene oxide-encapsulated gold nanoparticle that is very effective for the detection of the differentiation potential of neural stem cells (NSCs) based on surface-enhanced Raman spectroscopy (SERS). A new material, 3D GO-encapsulated gold nanoparticle, is developed to induce the double enhancement effect of graphene oxide and gold nanoparticle on SERS signals which is only effective for undifferentiated NSCs. The Raman peaks achieved from undifferentiated NSCs on the graphene oxide (GO)-encapsulated gold nanoparticles were 3.5 times higher than peaks obtained from normal metal structures and were clearly distinguishable from those of differentiated cells. The number of C=C bonds and the raman instensity at 1656cm−1 was found to show a positive correlation, which matches the differentiation state of the NSCs. Moreover, the substrate composed of 3D GO-encapsulated gold nanoparticles was also effective at distinguishing the differentiation state of single NSC by using electrochemical and electrical techniques. Hence, the proposed technique can be used as a powerful non-destructive in situ monitoring tool for the identification of the differentiation potential of various kinds of stem cells (mesenchymal, hematopoietic, and neural stem cells). PMID:23937915

Isolation and characterization of EG-like cells from Chinese swamp buffalo (Bubalus bubalis).

PubMed

Huang, Ben; Xie, Ti-San; Shi, De-Shun; Li, Tong; Wang, Xiao-Li; Mo, Yi; Wang, Zhi-Qiang; Li, Meng-Mei

2007-10-01

There have been few studies done on the isolation and characterization of Chinese swamp buffalo embryonic germ cells (EG cells). Here, we first report on EG-like cells isolated from Chinese swamp buffalo fetuses. The results showed the cells grew in large, multilayered colonies, which were densely packed with an obvious border resembling mouse embryonic stem cells (ES cells) and EG cells. The buffalo EG-like cells expressed AP, SSEA-1, SSEA-3, SSEA-4 and OCT-4. By RT-PCR, we found that undifferentiated swamp buffalo EG-like cells expressed the OCT-4, NANOG, SOX2, FOXD3, GP130, STAT3, and HEB gene mRNA, but not Fgf4. When these cells were cultured for more than 2weeks without passage, they could differentiate into several types of cells including fibroblast-like, neuron-like, smooth muscle-like, and epithelial-like cells. Some cells formed simple embryoid bodies (EBs) and cystic EBs by suspension culture. By RT-PCR, we found cystic EBs expressed FOXD3, GP130, STAT3 and HEB gene mRNA, but not OCT-4, NANOG, and SOX2 gene mRNA, which could be detected in undifferentiated buffalo EG-like cells. At the same time, the expression of KERATIN-14 (Endoderm), GATA4, ACTA2 (Mesoderm) and TUBB3 (Ectoderm) gene mRNA were also detected in cystic EBs. The results suggested that these cells were capable of forming three germ layers in in vitro differentiation. The expression of OCT-4, NANOG and SOX2 might be essential for Chinese swamp buffalo EG-like cells in a pluripotent state. During the isolation and culture of Chinese swamp buffalo EG-like cells, we found the fetuses that were at 30-80days post-coitus were more efficient than others; and the mechanical method was better than trypsin digestion. The maximal passage of the mechanical method was eight, but the trypsin digestion was just three passages. So it seemed like that the buffalo EG-like cells were sensitive to trypsin. In summary, we were the first to isolate and characterize Chinese swamp buffalo EG-like cells that had morphology and characterization similar to those of established EG/EG-like cells in mouse and human.

Isolation, characterization, and differentiation of stem cells for cartilage regeneration.

PubMed

Beane, Olivia S; Darling, Eric M

2012-10-01

The goal of tissue engineering is to create a functional replacement for tissues damaged by injury or disease. In many cases, impaired tissues cannot provide viable cells, leading to the investigation of stem cells as a possible alternative. Cartilage, in particular, may benefit from the use of stem cells since the tissue has low cellularity and cannot effectively repair itself. To address this need, researchers are investigating the chondrogenic capabilities of several multipotent stem cell sources, including adult and extra-embryonic mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), and induced pluripotent stem cells (iPSCs). Comparative studies indicate that each cell type has advantages and disadvantages, and while direct comparisons are difficult to make, published data suggest some sources may be more promising for cartilage regeneration than others. In this review, we identify current approaches for isolating and chondrogenically differentiating MSCs from bone marrow, fat, synovium, muscle, and peripheral blood, as well as cells from extra-embryonic tissues, ESCs, and iPSCs. Additionally, we assess chondrogenic induction with growth factors, identifying standard cocktails used for each stem cell type. Cell-only (pellet) and scaffold-based studies are also included, as is a discussion of in vivo results.

Commentary: "re-programming or selecting adult stem cells?".

PubMed

Trosko, James E

2008-01-01

The recent observations that embryonic stemness-associated genes could assist in the "de-differentiation" of adult skin fibroblast cells to "embryonic-like stem cells", using the "somatic cell nuclear transfer" techniques, have been interpreted as indicating a "re-programming" of genes. These reports have demonstrated a "proof of principle" approach to by-pass many, but not all, of the ethical, scientific and medical limitations of the "therapeutic cloning" of embryonic stem cells from embryos. However, while the interpretation that real "re-programming" of all those somatic fibroblastic differentiation genes might be correct, there does exists an alternative hypothesis of these exciting results. Based on the fact that multipotent adult stem cells exist in most, if not all, adult organs, the possibility exists that all these recent "re-programming" results, using the somatic nuclear transfer techniques, actually were the results of transferred rare nuclear material from the adult stem cells residing in the skin of the mouse, monkey and human samples. An examination of the rationale for this challenging hypothesis has been drawn from the hypothesis of the "stem cell theory of cancer", as well as from the field of human adult stem cells research.

Enrichment of undifferentiated type a spermatogonia from goat testis using discontinuous percoll density gradient and differential plating.

PubMed

Heidari, Banafsheh; Gifani, Minoo; Shirazi, Abolfazl; Zarnani, Amir-Hassan; Baradaran, Behzad; Naderi, Mohammad Mehdi; Behzadi, Bahareh; Borjian-Boroujeni, Sara; Sarvari, Ali; Lakpour, Niknam; Akhondi, Mohammad Mehdi

2014-04-01

The well documented source for adult multipotent stem cells is Spermatogonial Stem Cells (SSCs). They are the foundation of spermatogenesis in the testis throughout adult life by balancing self-renewal and differentiation. The aim of this study was to assess the effect of percoll density gradient and differential plating on enrichment of undifferentiated type A spermatogonia in dissociated cellular suspension of goat testes. Additionally, we evaluated the separated fractions of the gradients in percoll and samples in differential plating at different times for cell number, viability and purification rate of goat SSCs in culture. Testicular cells were successfully isolated from one month old goat testis using two-step enzymatic digestion and followed by two purification protocols, differential plating with different times of culture (3, 4, 5, and 6 hr) and discontinuous percoll density with different gradients (20, 28, 30, and 32%). The difference of percentage of undifferentiated SSCs (PGP9.5 positive) in each method was compared using ANOVA and comparison between the highest percentage of corresponding value between two methods was carried out by t-test using Sigma Stat (ver. 3.5). The highest PGP9.5 (94.6±0.4) and the lowest c-Kit positive (25.1±0.7) in Percoll method was significantly (p ≤ 0.001) achieved in 32% percoll gradient. While the corresponding rates in differential plating method for the highest PGP9.5 positive cells (81.3±1.1) and lowest c-Kit (17.1±1.4) was achieved after 5 hr culturing (p < 0.001). The enrichment of undifferentiated type A spermatogonia using Percoll was more efficient than differential plating method (p < 0.001). Percoll density gradient and differential plating were efficient and fast methods for enrichment of type A spermatogonial stem cells from goat testes.

Enrichment of Undifferentiated Type A Spermatogonia from Goat Testis Using Discontinuous Percoll Density Gradient and Differential Plating

PubMed Central

Heidari, Banafsheh; Gifani, Minoo; Shirazi, Abolfazl; Zarnani, Amir-Hassan; Baradaran, Behzad; Naderi, Mohammad Mehdi; Behzadi, Bahareh; Borjian-Boroujeni, Sara; Sarvari, Ali; Lakpour, Niknam; Akhondi, Mohammad Mehdi

2014-01-01

Background The well documented source for adult multipotent stem cells is Spermatogonial Stem Cells (SSCs). They are the foundation of spermatogenesis in the testis throughout adult life by balancing self-renewal and differentiation. The aim of this study was to assess the effect of percoll density gradient and differential plating on enrichment of undifferentiated type A spermatogonia in dissociated cellular suspension of goat testes. Additionally, we evaluated the separated fractions of the gradients in percoll and samples in differential plating at different times for cell number, viability and purification rate of goat SSCs in culture. Methods Testicular cells were successfully isolated from one month old goat testis using two-step enzymatic digestion and followed by two purification protocols, differential plating with different times of culture (3, 4, 5, and 6 hr) and discontinuous percoll density with different gradients (20, 28, 30, and 32%). The difference of percentage of undifferentiated SSCs (PGP9.5 positive) in each method was compared using ANOVA and comparison between the highest percentage of corresponding value between two methods was carried out by t-test using Sigma Stat (ver. 3.5). Results The highest PGP9.5 (94.6±0.4) and the lowest c-Kit positive (25.1±0.7) in Percoll method was significantly (p ≤ 0.001) achieved in 32% percoll gradient. While the corresponding rates in differential plating method for the highest PGP9.5 positive cells (81.3±1.1) and lowest c-Kit (17.1±1.4) was achieved after 5 hr culturing (p < 0.001). The enrichment of undifferentiated type A spermatogonia using Percoll was more efficient than differential plating method (p < 0.001). Conclusion Percoll density gradient and differential plating were efficient and fast methods for enrichment of type A spermatogonial stem cells from goat testes. PMID:24834311

Genetic Tools for Self-Organizing Culture of Mouse Embryonic Stem Cells via Small Regulatory RNA-Mediated Technologies, CRISPR/Cas9, and Inducible RNAi.

PubMed

Takata, Nozomu; Sakakura, Eriko; Sakuma, Tetsushi; Yamamoto, Takashi

2017-01-01

Approaches to investigate gene functions in experimental biology are becoming more diverse and reliable. Furthermore, several kinds of tissues and organs that possess their original identities can be generated in petri dishes from stem cells including embryonic, adult and induced pluripotent stem cells. Researchers now have several choices of experimental methods and their combinations to analyze gene functions in various biological systems. Here, as an example we describe one of the better protocols, which combines three-dimensional embryonic stem cell culture with small regulatory RNA-mediated technologies, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), and inducible RNA interference (RNAi). This protocol allows investigation of genes of interest to better understand gene functions in target tissues (or organs) during in vitro development.

Lineage-specific enhancers activate self-renewal genes in macrophages and embryonic stem cells.

PubMed

Soucie, Erinn L; Weng, Ziming; Geirsdóttir, Laufey; Molawi, Kaaweh; Maurizio, Julien; Fenouil, Romain; Mossadegh-Keller, Noushine; Gimenez, Gregory; VanHille, Laurent; Beniazza, Meryam; Favret, Jeremy; Berruyer, Carole; Perrin, Pierre; Hacohen, Nir; Andrau, J-C; Ferrier, Pierre; Dubreuil, Patrice; Sidow, Arend; Sieweke, Michael H

2016-02-12

Differentiated macrophages can self-renew in tissues and expand long term in culture, but the gene regulatory mechanisms that accomplish self-renewal in the differentiated state have remained unknown. Here we show that in mice, the transcription factors MafB and c-Maf repress a macrophage-specific enhancer repertoire associated with a gene network that controls self-renewal. Single-cell analysis revealed that, in vivo, proliferating resident macrophages can access this network by transient down-regulation of Maf transcription factors. The network also controls embryonic stem cell self-renewal but is associated with distinct embryonic stem cell-specific enhancers. This indicates that distinct lineage-specific enhancer platforms regulate a shared network of genes that control self-renewal potential in both stem and mature cells. Copyright © 2016, American Association for the Advancement of Science.

Effect of long-term culture of mouse embryonic stem cells under low oxygen concentration as well as on glycosaminoglycan hyaluronan on cell proliferation and differentiation.

PubMed

Ramírez, M Á; Pericuesta, E; Yáñez-Mó, M; Palasz, A; Gutiérrez-Adán, A

2011-02-01

Maintaining undifferentiated stem cells in defined conditions is of critical importance to improve their in vitro culture. We have evaluated the effects of culturing mouse stem (mES) cells under physiological oxygen concentration as well as by replacing fibroblast feeder layer (mEF) with gelatin or glycosaminoglycan hyaluronan (HA), on cell proliferation and differentiation. After 3 days culture or after long-term cell culture under different conditions, levels of apoptotic cell death were determined by cell cycle and TUNEL (TdT-mediated dUTP nick end labelling) assays and levels of cell proliferation by CFSE (5-(and-6)-carboxyfluorescein diacetate succinimidyl ester) labelling. We assessed spontaneous differentiation into cardiomyocytes and mRNA expression of pluripotency and differentiation biomarkers. After 3 days culture under hypoxic conditions, levels of proliferation and apoptosis of mES cells were higher, in correlation with increase in intracellular reactive oxygen species. However, when cells were continuously grown for 1 month under those conditions, the level of apoptosis was, in all cases, under 4%. Hypoxia reduced spontaneous differentiation of mES into cardiomyocytes. Long-term culture on HA was more effective in maintaining the pluripotent state of the mES cells when compared to that on gelatin. Level of terminal differentiation was highest on mEF, intermediate on HA and lowest on gelatin. Our data suggest that hypoxia is not necessary for maintaining pluripotency of mES cells and appeared to be detrimental during ES differentiation. Moreover, HA may offer a valuable alternative for long-term culture of mES cells in vitro. © 2010 Blackwell Publishing Ltd.

Human therapeutic cloning (NTSC): applying research from mammalian reproductive cloning.

PubMed

French, Andrew J; Wood, Samuel H; Trounson, Alan O

2006-01-01

Human therapeutic cloning or nuclear transfer stem cells (NTSC) to produce patient-specific stem cells, holds considerable promise in the field of regenerative medicine. The recent withdrawal of the only scientific publications claiming the successful generation of NTSC lines afford an opportunity to review the available research in mammalian reproductive somatic cell nuclear transfer (SCNT) with the goal of progressing human NTSC. The process of SCNT is prone to epigenetic abnormalities that contribute to very low success rates. Although there are high mortality rates in some species of cloned animals, most surviving clones have been shown to have normal phenotypic and physiological characteristics and to produce healthy offspring. This technology has been applied to an increasing number of mammals for utility in research, agriculture, conservation, and biomedicine. In contrast, attempts at SCNT to produce human embryonic stem cells (hESCs) have been disappointing. Only one group has published reliable evidence of success in deriving a cloned human blastocyst, using an undifferentiated hESC donor cell, and it failed to develop into a hESC line. When optimal conditions are present, it appears that in vitro development of cloned and parthenogenetic embryos, both of which may be utilized to produce hESCs, may be similar to in vitro fertilized embryos. The derivation of ESC lines from cloned embryos is substantially more efficient than the production of viable offspring. This review summarizes developments in mammalian reproductive cloning, cell-to-cell fusion alternatives, and strategies for oocyte procurement that may provide important clues facilitating progress in human therapeutic cloning leading to the successful application of cell-based therapies utilizing autologous hESC lines.

FOXM1 in sarcoma: role in cell cycle, pluripotency genes and stem cell pathways

PubMed Central

Kelleher, Fergal C.; O'sullivan, Hazel

2016-01-01

FOXM1 is a pro-proliferative transcription factor that promotes cell cycle progression at the G1-S, and G2-M transitions. It is activated by phosphorylation usually mediated by successive cyclin – cyclin dependent kinase complexes, and is highly expressed in sarcoma. p53 down regulates FOXM1 and FOXM1 inhibition is also partly dependent on Rb and p21. Abnormalities of p53 or Rb are frequent in sporadic sarcomas with bone or soft tissue sarcoma, accounting for 36% of index cancers in the high penetrance TP53 germline disorder, Li-Fraumeni syndrome. FOXM1 stimulates transcription of pluripotency related genes including SOX2, KLF4, OCT4, and NANOG many of which are important in sarcoma, a disorder of mesenchymal stem cell/ partially committed progenitor cells. In a selected specific, SOX2 is uniformly expressed in synovial sarcoma. Embryonic pathways preferentially used in stem cell such as Hippo, Hedgehog, and Wnt dominate in FOXM1 stoichiometry to alter rates of FOXM1 production or degradation. In undifferentiated pleomorphic sarcoma, liposarcoma, and fibrosarcoma, dysregulation of the Hippo pathway increases expression of the effector co-transcriptional activator Yes-Associated Protein (YAP). A complex involving YAP and the transcription factor TEAD elevates FOXM1 in these sarcoma subtypes. In another scenario 80% of desmoid tumors have nuclear localization of β-catenin, the Wnt pathway effector molecule. Thiazole antibiotics inhibit FOXM1 and because they have an auto-regulator loop FOXM1 expression is also inhibited. Current systemic treatment of sarcoma is of limited efficacy and inhibiting FOXM1 represents a potential new strategy. PMID:27074562

Induction of pluripotent stem cells from a cynomolgus monkey using a polycistronic simian immunodeficiency virus-based vector, differentiation toward functional cardiomyocytes, and generation of stably expressing reporter lines.

PubMed

Wunderlich, Stephanie; Haase, Alexandra; Merkert, Sylvia; Beier, Jennifer; Schwanke, Kristin; Schambach, Axel; Glage, Silke; Göhring, Gudrun; Curnow, Eliza C; Martin, Ulrich

2012-12-01

Induced pluripotent stem cells (iPSCs) represent a novel cell source for regenerative therapies. Many emerging iPSC-based therapeutic concepts will require preclinical evaluation in suitable large animal models. Among the large animal species frequently used in preclinical efficacy and safety studies, macaques show the highest similarities to humans at physiological, cellular, and molecular levels. We have generated iPSCs from cynomolgus monkeys (Macaca fascicularis) as a segue to regenerative therapy model development in this species. Because typical human immunodeficiency virus type 1 (HIV-1)-based lentiviral vectors show poor transduction of simian cells, a simian immunodeficiency virus (SIV)-based vector was chosen for efficient transduction of cynomolgus skin fibroblasts. A corresponding polycistronic vector with codon-optimized reprogramming factors was constructed for reprogramming. Growth characteristics as well as cell and colony morphology of the resulting cynomolgus iPSCs (cyiPSCs) were demonstrated to be almost identical to cynomolgus embryonic stem cells (cyESCs), and cyiPSCs expressed typical pluripotency markers including OCT4, SOX2, and NANOG. Furthermore, differentiation in vivo and in vitro into derivatives of all three germ layers, as well as generation of functional cardiomyocytes, could be demonstrated. Finally, a highly efficient technique for generation of transgenic cyiPSC clones with stable reporter expression in undifferentiated cells as well as differentiated transgenic cyiPSC progeny was developed to enable cell tracking in recipient animals. In conclusion, our data indicate that cyiPSCs represent a valuable cell source for establishment of macaque-based allogeneic and autologous preclinical cell transplantation models for various fields of regenerative medicine.

Reprogrammed mouse astrocytes retain a "memory" of tissue origin and possess more tendencies for neuronal differentiation than reprogrammed mouse embryonic fibroblasts.

PubMed

Tian, Changhai; Wang, Yongxiang; Sun, Lijun; Ma, Kangmu; Zheng, Jialin C

2011-02-01

Direct reprogramming of a variety of somatic cells with the transcription factors Oct4 (also called Pou5f1), Sox2 with either Klf4 and Myc or Lin28 and Nanog generates the induced pluripotent stem cells (iPSCs) with marker similarity to embryonic stem cells. However, the difference between iPSCs derived from different origins is unclear. In this study, we hypothesized that reprogrammed cells retain a "memory" of their origins and possess additional potential of related tissue differentiation. We reprogrammed primary mouse astrocytes via ectopic retroviral expression of OCT3/4, Sox2, Klf4 and Myc and found the iPSCs from mouse astrocytes expressed stem cell markers and formed teratomas in SCID mice containing derivatives of all three germ layers similar to mouse embryonic stem cells besides semblable morphologies. To test our hypothesis, we compared embryonic bodies (EBs) formation and neuronal differentiation between iPSCs from mouse embryonic fibroblasts (MEFsiPSCs) and iPSCs from mouse astrocytes (mAsiPSCs). We found that mAsiPSCs grew slower and possessed more potential for neuronal differentiation compared to MEFsiPSCs. Our results suggest that mAsiPSCs retain a "memory" of the central nervous system, which confers additional potential upon neuronal differentiation.

Subretinally transplanted embryonic stem cells rescue photoreceptor cells from degeneration in the RCS rats.

PubMed

Schraermeyer, U; Thumann, G; Luther, T; Kociok, N; Armhold, S; Kruttwig, K; Andressen, C; Addicks, K; Bartz-Schmidt, K U

2001-01-01

The Royal College of Surgeons (RCS) rat is an animal model for retinal degeneration such as the age-related macular degeneration. The RCS rat undergoes a progressive retinal degeneration during the early postnatal period. A potential treatment to prevent this retinal degeneration is the transplantation into the subretinal space of cells that would replace functions of the degenerating retinal pigment epithelium (RPE) cells or may form neurotrophic factors. In this study we have investigated the potential of subretinally transplanted embryonic stem cells to prevent the genetically determined photoreceptor cell degeneration in the RCS rat. Embryonic stem cells from the inner cell mass of the mouse blastocyst were allowed to differentiate to neural precursor cells in vitro and were then transplanted into the subretinal space of 20-day-old RCS rats. Transplanted and sham-operated rats were sacrificed 2 months following cell transplantation. The eyes were enucleated and photoreceptor degeneration was quantified by analyzing and determining the thickness of the outer nuclear layer by light and electron microscopy. In the eyes transplanted with embryonic cells up to 8 rows of photoreceptor cell nuclei were observed, whereas in nontreated control eyes the outer nuclear layer had degenerated completely. Transplantation of embryonic stem cells appears to delay photoreceptor cell degeneration in RCS rats.

Investigation of a redox-sensitive predictive model of mouse embryonic stem cells differentiation using quantitative nuclease protection assays and glutathione redox status

EPA Science Inventory

Investigation of a redox-sensitive predictive model of mouse embryonic stem cell differentiation via quantitative nuclease protection assays and glutathione redox status Chandler KJ,Hansen JM, Knudsen T,and Hunter ES 1. U.S. Environmental Protection Agency, Research Triangl...

Identifying developmental toxicity pathways for a subset of ToxCast chemicals using human embryonic stem cells and metabolomics

EPA Science Inventory

Metabolomics analysis was performed on the supernatant of human embryonic stem (hES) cell cultures exposed to a blinded subset of 11 chemicals selected from the chemical library of EPA's ToxCast™ chemical screening and prioritization research project. Metabolites from hES cultur...

Screening ToxCast™ Phase I Chemicals in a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) Assay

EPA Science Inventory

An Adherent Cell Differentiation and Cytotoxicity (ACDC) in vitro assay with mouse embryonic stem cells was used to screen the ToxCast Phase I chemical library for effects on cellular differentiation and cell number. The U.S. Environmental Protection Agency (EPA) established the ...

Neuronal Subtype Generation During Postnatal Olfactory Bulb Neurogenesis.

PubMed

Angelova, Alexandra; Tiveron, Marie-Catherine; Cremer, Harold; Beclin, Christophe

2018-01-01

In the perinatal and adult forebrain, regionalized neural stem cells lining the ventricular walls produce different types of olfactory bulb interneurons. Although these postnatal stem cells are lineage related to their embryonic counterparts that produce, for example, cortical, septal, and striatal neurons, their output at the level of neuronal phenotype changes dramatically. Tiveron et al. investigated the molecular determinants underlying stem cell regionalization and the gene expression changes inducing the shift from embryonic to adult neuron production. High-resolution gene expression analyses of different lineages revealed that the zinc finger proteins, Zic1 and Zic2, are postnatally induced in the dorsal olfactory bulb neuron lineage. Functional studies demonstrated that these factors confer a GABAergic and calretinin-positive phenotype to neural stem cells while repressing dopaminergic fate. Based on these findings, we discuss the molecular mechanisms that allow acquisition of new traits during the transition from embryonic to adult neurogenesis. We focus on the involvement of epigenetic marks and emphasize why the identification of master transcription factors, that instruct the fate of postnatally generated neurons, can help in deciphering the mechanisms driving fate transition from embryonic to adult neuron production.

LSD1 demethylase and the methyl-binding protein PHF20L1 prevent SET7 methyltransferase-dependent proteolysis of the stem-cell protein SOX2.

PubMed

Zhang, Chunxiao; Hoang, Nam; Leng, Feng; Saxena, Lovely; Lee, Logan; Alejo, Salvador; Qi, Dandan; Khal, Anthony; Sun, Hong; Lu, Fei; Zhang, Hui

2018-03-09

The pluripotency-controlling stem-cell protein SRY-box 2 (SOX2) plays a pivotal role in maintaining the self-renewal and pluripotency of embryonic stem cells and also of teratocarcinoma or embryonic carcinoma cells. SOX2 is monomethylated at lysine 119 (Lys-119) in mouse embryonic stem cells by the SET7 methyltransferase, and this methylation triggers ubiquitin-dependent SOX2 proteolysis. However, the molecular regulators and mechanisms controlling SET7-induced SOX2 proteolysis are unknown. Here, we report that in human ovarian teratocarcinoma PA-1 cells, methylation-dependent SOX2 proteolysis is dynamically regulated by the LSD1 lysine demethylase and a methyl-binding protein, PHD finger protein 20-like 1 (PHF20L1). We found that LSD1 not only removes the methyl group from monomethylated Lys-117 (equivalent to Lys-119 in mouse SOX2), but it also demethylates monomethylated Lys-42 in SOX2, a reaction that SET7 also regulated and that also triggered SOX2 proteolysis. Our studies further revealed that PHF20L1 binds both monomethylated Lys-42 and Lys-117 in SOX2 and thereby prevents SOX2 proteolysis. Down-regulation of either LSD1 or PHF20L1 promoted SOX2 proteolysis, which was prevented by SET7 inactivation in both PA-1 and mouse embryonic stem cells. Our studies also disclosed that LSD1 and PHF20L1 normally regulate the growth of pluripotent mouse embryonic stem cells and PA-1 cells by preventing methylation-dependent SOX2 proteolysis. In conclusion, our findings reveal an important mechanism by which the stability of the pluripotency-controlling stem-cell protein SOX2 is dynamically regulated by the activities of SET7, LSD1, and PHF20L1 in pluripotent stem cells. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Combination Chemotherapy and Peripheral Stem Cell Transplantation in Treating Patients With Stage III Ovarian Cancer

ClinicalTrials.gov

2017-08-08

Malignant Ovarian Mixed Epithelial Tumor; Ovarian Clear Cell Cystadenocarcinoma; Ovarian Endometrioid Adenocarcinoma; Ovarian Mucinous Cystadenocarcinoma; Ovarian Serous Cystadenocarcinoma; Primary Peritoneal Carcinoma; Stage III Ovarian Cancer; Undifferentiated Ovarian Carcinoma

[Undifferentiated (embryonal) sarcoma of the liver. Report of a case].

PubMed

Orozco, H; Mercado, M A; Takahashi, T; Chan, C; Quintanilla, L; Jiménez, M; Sosa, R; Esquivel, E

1991-01-01

A 15-year-old woman who was studied because an abdominal mass at the Instituto Nacional de la Nutricion Salvador Zubiran (INNSZ) is reported. The history revealed only malaise and mild abdominal pain. At physical exploration, an abdominal mass in the upper right quadrant was found. Liver function tests were normal. Abdominal ultrasound and computerized tomography revealed a large cystic mass of the right hepatic lobe. She underwent exploratory laparotomy. Intraoperative frozen sections of the biopsies demonstrated undifferentiated sarcoma of the liver, and an extended right trisegmentectomy was performed. Postoperative outcome was uneventful. Adjuvant treatment with doxorubicin and dacarbazine was given, and at six months of follow-up, the patient is alive without any evidence of recurrence. Clinical and histopathologic features of this rare malignant tumor are discussed, as well as the therapeutic choices.

Autonomous assembly of epithelial structures by subrenal implantation of dissociated embryonic inner-ear cells.

PubMed

Wang, Li; Zhang, Kaiqing; Zhu, Helen He; Gao, Wei-Qiang

2015-05-27

Microenvironment and cell-cell interactions play an important role during embryogenesis and are required for the stemness and differentiation of stem cells. The inner-ear sensory epithelium, containing hair cells and supporting cells, is derived from the stem cells within the otic vesicle at early embryonic stages. However, whether or not such microenvironment or cell-cell interactions within the embryonic otic tissue have the capacity to regulate the proliferation and differentiation of stem cells and to autonomously reassemble the cells into epithelial structures is unknown. Here, we report that on enzymatic digestion and dissociation to harvest all the single cells from 13.5-day-old rat embryonic (E13.5) inner-ear tissue as well as on implantation of these cells under renal capsules; the dissociated cells are able to reassemble themselves to form epithelial structures as early as 7 days after implantation. By 25 days after implantation, more mature epithelial structures are formed. Immunostaining with cell-type-specific markers reveals that hair cells and supporting cells are not only formed, but are also well aligned with the hair cells located in the apical layer surrounded by the supporting cells. These findings suggest that microenvironment and cell-cell interactions within the embryonic inner-ear tissue have the autonomous signals to induce the formation of sensory epithelial structures. This method may also provide a useful system to study the potential of stem cells to differentiate into hair cells in vivo.

miR-203 modulates epithelial differentiation of human embryonic stem cells towards epidermal stratification.

PubMed

Nissan, Xavier; Denis, Jérôme Alexandre; Saidani, Manoubia; Lemaitre, Gilles; Peschanski, Marc; Baldeschi, Christine

2011-08-15

The molecular mechanisms controlling the differentiation of human basal keratinocyte stem cells towards the epidermis are well characterized, whereas the earliest process leading to the specification of embryonic stem cells into keratinocytes is still not well understood. MicroRNAs are regulators of many cellular events, but evidence for microRNA acting on the differentiation of human embryonic stem cells into a specific lineage has been elusive. By using our recent protocol for obtaining functional keratinocytes from hESC, we attempted to analyze the role of microRNAs in the early stages of epidermal differentiation. Thus, we identified a set of 5 microRNAs, namely miR-200a, miR-200b, miR-203, miR-205 and miR-429, that are specifically overexpressed during the early stages of the differentiation process. Interestingly, our functional analyses revealed an instrumental role of miR-203, which had been previously shown to play a key role during the formation of the pluristratified epidermis by basal keratinocyte stem cells, in the early keratinocyte commitment. These results highlight the determinant and unique role of miR-203 during the entire process of epidermal development by extending its spectrum of action from the early commitment of embryonic stem cells to ultimate differentiation of the organ. Copyright © 2011 Elsevier Inc. All rights reserved.

Production of embryonic and fetal-like red blood cells from human induced pluripotent stem cells.

PubMed

Chang, Chan-Jung; Mitra, Koyel; Koya, Mariko; Velho, Michelle; Desprat, Romain; Lenz, Jack; Bouhassira, Eric E

2011-01-01

We have previously shown that human embryonic stem cells can be differentiated into embryonic and fetal type of red blood cells that sequentially express three types of hemoglobins recapitulating early human erythropoiesis. We report here that we have produced iPS from three somatic cell types: adult skin fibroblasts as well as embryonic and fetal mesenchymal stem cells. We show that regardless of the age of the donor cells, the iPS produced are fully reprogrammed into a pluripotent state that is undistinguishable from that of hESCs by low and high-throughput expression and detailed analysis of globin expression patterns by HPLC. This suggests that reprogramming with the four original Yamanaka pluripotency factors leads to complete erasure of all functionally important epigenetic marks associated with erythroid differentiation regardless of the age or the tissue type of the donor cells, at least as detected in these assays. The ability to produce large number of erythroid cells with embryonic and fetal-like characteristics is likely to have many translational applications.

Publishing SNP genotypes of human embryonic stem cell lines: policy statement of the International Stem Cell Forum Ethics Working Party.

PubMed

Knoppers, Bartha M; Isasi, Rosario; Benvenisty, Nissim; Kim, Ock-Joo; Lomax, Geoffrey; Morris, Clive; Murray, Thomas H; Lee, Eng Hin; Perry, Margery; Richardson, Genevra; Sipp, Douglas; Tanner, Klaus; Wahlström, Jan; de Wert, Guido; Zeng, Fanyi

2011-09-01

Novel methods and associated tools permitting individual identification in publicly accessible SNP databases have become a debatable issue. There is growing concern that current technical and ethical safeguards to protect the identities of donors could be insufficient. In the context of human embryonic stem cell research, there are no studies focusing on the probability that an hESC line donor could be identified by analyzing published SNP profiles and associated genotypic and phenotypic information. We present the International Stem Cell Forum (ISCF) Ethics Working Party's Policy Statement on "Publishing SNP Genotypes of Human Embryonic Stem Cell Lines (hESC)". The Statement prospectively addresses issues surrounding the publication of genotypic data and associated annotations of hESC lines in open access databases. It proposes a balanced approach between the goals of open science and data sharing with the respect for fundamental bioethical principles (autonomy, privacy, beneficence, justice and research merit and integrity).

Murine mesenchymal and embryonic stem cells express a similar Hox gene profile.

PubMed

Phinney, Donald G; Gray, Andrew J; Hill, Katy; Pandey, Amitabh

2005-12-30

Using degenerate oligonucleotide primers targeting the homeobox domain, we amplified by PCR and sequenced 723 clones from five murine cell populations and lines derived from embryonic mesoderm and adult bone marrow. Transcripts from all four vertebrate Hox clusters were expressed by the different populations. Hierarchical clustering of the data revealed that mesenchymal stem cells (MSCs) and the embryonic stem (ES) cell line D3 shared a similar Hox expression profile. These populations exclusively expressed Hoxb2, Hoxb5, Hoxb7, and Hoxc4, transcripts regulating self-renewal and differentiation of other stem cells. Additionally, Hoxa7 transcript quantified by real-time PCR strongly correlated (r2=0.89) with the number of Hoxa7 clones identified by sequencing, validating that data from the PCR screen reflects differences in Hox mRNA abundance between populations. This is the first study to catalogue Hox transcripts in murine MSCs and by comparative analyses identify specific Hox genes that may contribute to their stem cell character.

Fine structures of embryonic discs of in vivo post-hatching porcine blastocysts at the pre-primitive streak stage.

PubMed

Xia, P; Liu, Z; Qin, P

2011-04-01

To date, reports about the ultrastructure of porcine embryonic discs have not shown details of the primitive streak. The main objective of this study was to examine the ultrastructure of interior and exterior embryonic discs in porcine in vivo blastocysts with diameters of 1, 3 and 9 mm using scanning electron microscopy and transmission electron microscopy. For the first time, we revealed the ultrastructure of the unusual group of cells in the pre-primitive streak area of embryonic discs. The cells were 1-2 μm in diameter, had high electron density and contained abundant, free ribosomes and endoplasmic reticulum. These primitive streak cells could represent original embryonic stem cells or represent a stem cell niche. The results also showed three types of cells on the exterior surface of the embryonic discs. Moreover, our results provided morphological evidence of condensed nuclei in the smooth cells on the surface of the embryonic disc. © 2010 Blackwell Verlag GmbH.

Use of Stirred Suspension Bioreactors for Male Germ Cell Enrichment.

PubMed

Sakib, Sadman; Dores, Camila; Rancourt, Derrick; Dobrinski, Ina

2016-01-01

Spermatogenesis is a stem cell based system. Both therapeutic and biomedical research applications of spermatogonial stem cells require a large number of cells. However, there are only few germ line stem cells in the testis, contained in the fraction of undifferentiated spermatogonia. The lack of specific markers makes it difficult to isolate these cells. The long term maintenance and proliferation of nonrodent germ cells in culture has so far been met with limited success, partially due to the lack of highly enriched starting populations. Differential plating, which depends on the differential adhesion properties of testicular somatic and germ cells to tissue culture dishes, has been the method of choice for germ cell enrichment, especially for nonrodent germ cells. However, for large animals, this process becomes labor intensive and increases variability due to the need for extensive handling. Here, we describe the use of stirred suspension bioreactors, as a novel system for enriching undifferentiated germ cells from 1-week-old pigs. This method capitalizes on the adherent properties of somatic cells within a controlled environment, thus promoting the enrichment of progenitor cells with minimal handling and variability.

Defining the Genomic Signature of Totipotency and Pluripotency during Early Human Development

PubMed Central

Galan, Amparo; Diaz-Gimeno, Patricia; Poo, Maria Eugenia; Valbuena, Diana; Sanchez, Eva; Ruiz, Veronica; Dopazo, Joaquin; Montaner, David; Conesa, Ana; Simon, Carlos

2013-01-01

The genetic mechanisms governing human pre-implantation embryo development and the in vitro counterparts, human embryonic stem cells (hESCs), still remain incomplete. Previous global genome studies demonstrated that totipotent blastomeres from day-3 human embryos and pluripotent inner cell masses (ICMs) from blastocysts, display unique and differing transcriptomes. Nevertheless, comparative gene expression analysis has revealed that no significant differences exist between hESCs derived from blastomeres versus those obtained from ICMs, suggesting that pluripotent hESCs involve a new developmental progression. To understand early human stages evolution, we developed an undifferentiation network signature (UNS) and applied it to a differential gene expression profile between single blastomeres from day-3 embryos, ICMs and hESCs. This allowed us to establish a unique signature composed of highly interconnected genes characteristic of totipotency (61 genes), in vivo pluripotency (20 genes), and in vitro pluripotency (107 genes), and which are also proprietary according to functional analysis. This systems biology approach has led to an improved understanding of the molecular and signaling processes governing human pre-implantation embryo development, as well as enabling us to comprehend how hESCs might adapt to in vitro culture conditions. PMID:23614026

GSK3 as a Sensor Determining Cell Fate in the Brain.

PubMed

Cole, Adam R

2012-01-01

Glycogen synthase kinase 3 (GSK3) is an unusual serine/threonine kinase that controls many neuronal functions, including neurite outgrowth, synapse formation, neurotransmission, and neurogenesis. It mediates these functions by phosphorylating a wide range of substrates involved in gene transcription, metabolism, apoptosis, cytoskeletal dynamics, signal transduction, lipid membrane dynamics, and trafficking, amongst others. This complicated list of diverse substrates generally follow a more simple pattern: substrates negatively regulated by GSK3-mediated phosphorylation favor a proliferative/survival state, while substrates positively regulated by GSK3 favor a more differentiated/functional state. Accordingly, GSK3 activity is higher in differentiated cells than undifferentiated cells and physiological (Wnt, growth factors) and pharmacological inhibitors of GSK3 promote the proliferative capacity of embryonic stem cells. In the brain, the level of GSK3 activity influences neural progenitor cell proliferation/differentiation in neuroplasticity and repair, as well as efficient neurotransmission in differentiated adult neurons. While defects in GSK3 activity are unlikely to be the primary cause of neurodegenerative diseases, therapeutic regulation of its activity to promote a proliferative/survival versus differentiated/mature functional environment in the brain could be a powerful strategy for treatment of neurodegenerative and other mental disorders.

GSK3 as a Sensor Determining Cell Fate in the Brain

PubMed Central

Cole, Adam R.

2012-01-01

Glycogen synthase kinase 3 (GSK3) is an unusual serine/threonine kinase that controls many neuronal functions, including neurite outgrowth, synapse formation, neurotransmission, and neurogenesis. It mediates these functions by phosphorylating a wide range of substrates involved in gene transcription, metabolism, apoptosis, cytoskeletal dynamics, signal transduction, lipid membrane dynamics, and trafficking, amongst others. This complicated list of diverse substrates generally follow a more simple pattern: substrates negatively regulated by GSK3-mediated phosphorylation favor a proliferative/survival state, while substrates positively regulated by GSK3 favor a more differentiated/functional state. Accordingly, GSK3 activity is higher in differentiated cells than undifferentiated cells and physiological (Wnt, growth factors) and pharmacological inhibitors of GSK3 promote the proliferative capacity of embryonic stem cells. In the brain, the level of GSK3 activity influences neural progenitor cell proliferation/differentiation in neuroplasticity and repair, as well as efficient neurotransmission in differentiated adult neurons. While defects in GSK3 activity are unlikely to be the primary cause of neurodegenerative diseases, therapeutic regulation of its activity to promote a proliferative/survival versus differentiated/mature functional environment in the brain could be a powerful strategy for treatment of neurodegenerative and other mental disorders. PMID:22363258

Totipotency, Pluripotency and Nuclear Reprogramming

NASA Astrophysics Data System (ADS)

Mitalipov, Shoukhrat; Wolf, Don

Mammalian development commences with the totipotent zygote which is capable of developing into all the specialized cells that make up the adult animal. As development unfolds, cells of the early embryo proliferate and differentiate into the first two lineages, the pluripotent inner cell mass and the trophectoderm. Pluripotent cells can be isolated, adapted and propagated indefinitely in vitro in an undifferentiated state as embryonic stem cells (ESCs). ESCs retain their ability to differentiate into cells representing the three major germ layers: endoderm, mesoderm or ectoderm or any of the 200+ cell types present in the adult body. Since many human diseases result from defects in a single cell type, pluripotent human ESCs represent an unlimited source of any cell or tissue type for replacement therapy thus providing a possible cure for many devastating conditions. Pluripotent cells resembling ESCs can also be derived experimentally by the nuclear reprogramming of somatic cells. Reprogrammed somatic cells may have an even more important role in cell replacement therapies since the patient's own somatic cells can be used for reprogramming thereby eliminating immune based rejection of transplanted cells. In this review, we summarize two major approaches to reprogramming: (1) somatic cell nuclear transfer and (2) direct reprogramming using genetic manipulations.

Eliminating Cancer Stem Cells by Targeting Embryonic Signaling Pathways.

PubMed

Oren, Ohad; Smith, B Douglas

2017-02-01

Dramatic advances have been made in the understanding of cancer over the past decade. Prime among those are better appreciation of the biology of cancer and the development of targeted therapies. Despite these improvements, however, most tumors remain refractory to anti-cancer medications and frequently recur. Cancer Stem Cells (CSCs), which in some cases express markers of pluripotency (e.g., Oct-4), share many of the molecular features of normal stem cells. These cells have been hypothesised to play a role in tumor resistance and relapse. They exhibit dependence on many primitive regulatory pathways and may be best viewed in the context of embryonic signaling pathways. In this article, we review important embryonic signaling cascades and their differential expression in CSCs. We also discuss these pathways as actionable targets for novel therapies in hopes that eliminating cancer stem cells will lead to an improvement in overall survival for patients.

Stem cell potency and the ability to contribute to chimeric organisms.

PubMed

Polejaeva, Irina; Mitalipov, Shoukhrat

2013-03-01

Mouse embryonic chimeras are a well-established tool for studying cell lineage commitment and pluripotency. Experimental chimeras were successfully produced by combining two or more preimplantation embryos or by introducing into host embryo cultured pluripotent embryonic stem cells (ESCs). Chimera production using genetically modified ESCs became the method of choice for the generation of knockout or knockin mice. Although the derivation of ESCs or ESC-like cells has been reported for other species, only mouse and rat pluripotent stem cells have been shown to contribute to germline-competent chimeras, which is the defining feature of ESCs. Herein, we describe different approaches employed for the generation of embryonic chimeras, define chimera-competent cell types, and describe cases of spontaneous chimerism in humans. We also review the current state of derivation of pluripotent stem cells in several species and discuss outcomes of various chimera studies when such cells are used.

Feeder-cell-independent culture of the pig-embryonic-stem-cell-derived exocrine pancreatic cell line, PICM-31

USDA-ARS?s Scientific Manuscript database

The adaptation to feeder-independent growth of a pig embryonic stem cell-derived pancreatic cell line is described. The parental PICM-31 cell line, previously characterized as an exocrine pancreas cell line, was colony-cloned two times in succession resulting in the subclonal cell line, PICM-31A1. P...

3 CFR 8446 - Proclamation 8446 of October 30, 2009. National Alzheimer's Disease Awareness Month, 2009

Code of Federal Regulations, 2010 CFR

2010-01-01

..., we must leave no avenue unexplored. Embryonic stem cells may hold the key for us to better understand... Executive Order lifting the ban on Federal funding for embryonic stem cell research, with proper guidelines... are now able to start treatments earlier, slowing the loss of brain cells and the progression of...

Effects of the EVCAM chemical validation library on differentiation using marker gene expression in lmouse embryonic stem cells

EPA Science Inventory

The adherent cell differentiation and cytotoxicity (ACDC) assay was used to profile the effects of the ECVAM EST validation chemical library (19 compounds) on J1 mouse embryonic stem cells (mESC). PCR-based TaqMan Low Density Arrays (TLDA) provided a high-content assessment of al...

Shrink-film configurable multiscale wrinkles for functional alignment of human embryonic stem cells and their cardiac derivatives.

PubMed

Chen, Aaron; Lieu, Deborah K; Freschauf, Lauren; Lew, Valerie; Sharma, Himanshu; Wang, Jiaxian; Nguyen, Diep; Karakikes, Ioannis; Hajjar, Roger J; Gopinathan, Ajay; Botvinick, Elliot; Fowlkes, Charless C; Li, Ronald A; Khine, Michelle

2011-12-22

A biomimetic substrate for cell-culture is fabricated by plasma treatment of a prestressed thermoplastic shrink film to create tunable multiscaled alignment "wrinkles". Using this substrate, the functional alignment of human embryonic stem cell derived cardiomyocytes is demonstrated. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evaluation of an adherent mouse embryonic stem cell in vitro assay to predict developmental toxicity of ToxCast chemicals.

EPA Science Inventory

The potential for most environmental chemicals to produce developmental toxicity is unknown. Mouse embryonic stem cell (mESC) assays are an alternative in vitro model to assess chemicals. The chemical space evaluated using mESC and compared to in vivo is limited. We used an adher...

Peripheral Motor and Sensory Nerve Conduction following Transplantation of Undifferentiated Autologous Adipose Tissue-Derived Stem Cells in a Biodegradable U.S. Food and Drug Administration-Approved Nerve Conduit.

PubMed

Klein, Silvan M; Vykoukal, Jody; Li, De-Pei; Pan, Hui-Lin; Zeitler, Katharina; Alt, Eckhard; Geis, Sebastian; Felthaus, Oliver; Prantl, Lukas

2016-07-01

Conduits preseeded with either Schwann cells or stem cells differentiated into Schwann cells demonstrated promising results for the outcome of nerve regeneration in nerve defects. The concept of this trial combines nerve repair by means of a commercially available nerve guidance conduit and preseeding with autologous, undifferentiated, adipose tissue-derived stem cells. Adipose tissue-derived stem cells were harvested from rats and subsequently seeded onto a U.S. Food and Drug Administration-approved type I collagen conduit. Sciatic nerve gaps 10 mm in length were created, and nerve repair was performed by the transplantation of either conduits preseeded with autologous adipose tissue-derived stem cells or acellular (control group) conduits. After 6 months, the motor and sensory nerve conduction velocity were assessed. Nerves were removed and examined by hematoxylin and eosin, van Gieson, and immunohistochemistry (S100 protein) staining for the quality of axonal regeneration. Nerve gaps treated with adipose tissue-derived stem cells showed superior nerve regeneration, reflected by higher motor and sensory nerve conduction velocity values. The motor and sensory nerve conduction velocity were significantly greater in nerves treated with conduits preseeded with adipose tissue-derived stem cells than in nerves treated with conduits alone (p < 0.05). Increased S100 immunoreactivity was detected for the adipose tissue-derived stem cell group. In this group, axon arrangement inside the conduits was more organized. Transplantation of adipose tissue-derived stem cells significantly improves motor and sensory nerve conduction velocity in peripheral nerve gaps. Preseeded conduits showed a more organized axon arrangement inside the conduit in comparison with nerve conduits alone. The approach used here could readily be translated into a clinical therapy. Therapeutic, V.

Differentiation of Human Dental Stem Cells Reveal a Role for microRNA-218

PubMed Central

Gay, Isabel; Cavender, Adriana; Peto, David; Sun, Zhao; Speer, Aline; Cao, Huojun; Amendt, Brad A.

2013-01-01

Background Regeneration of the lost periodontium is the ultimate goal of periodontal therapy. Advances in tissue engineering have demonstrated the multilineage potential and plasticity of adult stem cells located in the periodontal apparatus. However, it remains unclear how epigenetic mechanisms controlling signals determine tissue specification and cell lineage decisions. To date, no data is available on micro-RNAs (miRNAs) activity behind human-derived dental stem cells. Methods In this study, we isolated periodontal ligament stem cells (PDLSCs), dental pulp stem cells (DPSCs), and gingival stem cells (GSCs) from extracted third molars; human bone marrow stem cells (BMSCs) were used as a positive control. The expression of OCT4A and NANOG was confirmed in these undifferentiated cells. All cells were cultured under osteogenic inductive conditions and RUNX2 expression was analyzed as a marker of mineralized tissue differentiation. A miRNA expression profile was obtained at baseline and after osteogenic induction in all cell types. Results RUNX2 expression demonstrated the successful osteogenic induction of all cell types, which was confirmed by alizarin red stain. The analysis of 765 miRNAs demonstrated a shift in miRNA expression occurred in all four stem cell types, including a decrease in hsa-mir-218 across all differentiated cell populations. Hsa-mir-218 targets RUNX2 and decreases RUNX2 expression in undifferentiated human dental stem cells (DSCs). DSC mineralized tissue type differentiation is associated with a decrease in hsa-mir-218 expression. Conclusions These data reveal a miRNA regulated pathway for the differentiation of human DSCs and a select network of human microRNAs that control DSC osteogenic differentiation. PMID:23662917

Therapeutic cloning and cellular reprogramming.

PubMed

Rodriguez, Ramon M; Ross, Pablo J; Cibelli, Jose B

2012-01-01

Embryonic stem cells are capable of differentiating into any cell-type present in an adult organism, and constitute a renewable source of tissue for regenerative therapies. The transplant of allogenic stem cells is challenging due to the risk of immune rejection. Nevertheless, somatic cell reprogramming techniques allow the generation of isogenic embryonic stem cells, genetically identical to the patient. In this chapter we will discuss the cellular reprogramming techniques in the context of regenerative therapy and the biological and technical barriers that they will need to overcome before clinical use.

Multipotent adult germ-line stem cells, like other pluripotent stem cells, can be killed by cytotoxic T lymphocytes despite low expression of major histocompatibility complex class I molecules

PubMed Central

Dressel, Ralf; Guan, Kaomei; Nolte, Jessica; Elsner, Leslie; Monecke, Sebastian; Nayernia, Karim; Hasenfuss, Gerd; Engel, Wolfgang

2009-01-01

Background Multipotent adult germ-line stem cells (maGSCs) represent a new pluripotent cell type that can be derived without genetic manipulation from spermatogonial stem cells (SSCs) present in adult testis. Similarly to induced pluripotent stem cells (iPSCs), they could provide a source of cellular grafts for new transplantation therapies of a broad variety of diseases. To test whether these stem cells can be rejected by the recipients, we have analyzed whether maGSCs and iPSCs can become targets for cytotoxic T lymphocytes (CTL) or whether they are protected, as previously proposed for embryonic stem cells (ESCs). Results We have observed that maGSCs can be maintained in prolonged culture with or without leukemia inhibitory factor and/or feeder cells and still retain the capacity to form teratomas in immunodeficient recipients. They were, however, rejected in immunocompetent allogeneic recipients, and the immune response controlled teratoma growth. We analyzed the susceptibility of three maGSC lines to CTL in comparison to ESCs, iPSCs, and F9 teratocarcinoma cells. Major histocompatibility complex (MHC) class I molecules were not detectable by flow cytometry on these stem cell lines, apart from low levels on one maGSC line (maGSC Stra8 SSC5). However, using a quantitative real time PCR analysis H2K and B2m transcripts were detected in all pluripotent stem cell lines. All pluripotent stem cell lines were killed in a peptide-dependent manner by activated CTLs derived from T cell receptor transgenic OT-I mice after pulsing of the targets with the SIINFEKL peptide. Conclusion Pluripotent stem cells, including maGSCs, ESCs, and iPSCs can become targets for CTLs, even if the expression level of MHC class I molecules is below the detection limit of flow cytometry. Thus they are not protected against CTL-mediated cytotoxicity. Therefore, pluripotent cells might be rejected after transplantation by this mechanism if specific antigens are presented and if specific activated CTLs are present. Our results show that the adaptive immune system has in principle the capacity to kill pluripotent and teratoma forming stem cells. This finding might help to develop new strategies to increase the safety of future transplantations of in vitro differentiated cells by exploiting a selective immune response against contaminating undifferentiated cells. Reviewers This article was reviewed by Bhagirath Singh, Etienne Joly and Lutz Walter. PMID:19715575

[Stem cells--cloning, plasticity, bioethic].

PubMed

Pflegerl, Pamina; Keller, Thomas; Hantusch, Brigitte; Hoffmann, Thomas Sören; Kenner, Lukas

2008-01-01

Stem cells with certain characteristics have become promising tools for molecular medicine. They have the potential to self-regenerate and to differentiate into specific tissues. Besides their great potential, embryonic stem cells (ESC) run the risk of enhanced tumorigenesis. The use of human embryonic stem cells (hESC) is ethically problematic because their isolation involves the destruction of human embryos. Recently developed methods generate are able to pluripotent stem cells from fibroblasts. Alternatives for ESC are adult stem cells (ASC) derived from bone marrow, cord blood, amniotic fluid and other tissues. The following article is on the basis of testimony of Lukas Kenner for the German Bundestag about the use of ESC for research, therapy and drug development. Ethical aspects are taken into consideration.

Current status of stem cells in cardiac repair.

PubMed

Henning, Robert J

2018-03-01

One out of every two men and one out of every three women greater than the age of 40 will experience an acute myocardial infarction (AMI) at some time during their lifetime. As more patients survive their AMIs, the incidence of congestive heart failure (CHF) is increasing. 6 million people in the USA have ischemic cardiomyopathies and CHF. The search for new and innovative treatments for patients with AMI and CHF has led to investigations and use of human embryonic stem cells, cardiac stem/progenitor cells, bone marrow-derived mononuclear cells and mesenchymal stem cells for treatment of these heart conditions. This paper reviews current investigations with human embryonic, cardiac, bone marrow and mesenchymal stem cells, and also stem cell paracrine factors and exosomes.

Expansion on Stromal Cells Preserves the Undifferentiated State of Human Hematopoietic Stem Cells Despite Compromised Reconstitution Ability

PubMed Central

Magnusson, Mattias; Sierra, Maria I.; Sasidharan, Rajkumar; Prashad, Sacha L.; Romero, Melissa; Saarikoski, Pamela; Van Handel, Ben; Huang, Andy; Li, Xinmin; Mikkola, Hanna K. A.

2013-01-01

Lack of HLA-matched hematopoietic stem cells (HSC) limits the number of patients with life-threatening blood disorders that can be treated by HSC transplantation. So far, insufficient understanding of the regulatory mechanisms governing human HSC has precluded the development of effective protocols for culturing HSC for therapeutic use and molecular studies. We defined a culture system using OP9M2 mesenchymal stem cell (MSC) stroma that protects human hematopoietic stem/progenitor cells (HSPC) from differentiation and apoptosis. In addition, it facilitates a dramatic expansion of multipotent progenitors that retain the immunophenotype (CD34+CD38−CD90+) characteristic of human HSPC and proliferative potential over several weeks in culture. In contrast, transplantable HSC could be maintained, but not significantly expanded, during 2-week culture. Temporal analysis of the transcriptome of the ex vivo expanded CD34+CD38−CD90+ cells documented remarkable stability of most transcriptional regulators known to govern the undifferentiated HSC state. Nevertheless, it revealed dynamic fluctuations in transcriptional programs that associate with HSC behavior and may compromise HSC function, such as dysregulation of PBX1 regulated genetic networks. This culture system serves now as a platform for modeling human multilineage hematopoietic stem/progenitor cell hierarchy and studying the complex regulation of HSC identity and function required for successful ex vivo expansion of transplantable HSC. PMID:23342037

The role of undifferentiated adipose-derived stem cells in peripheral nerve repair.

PubMed

Zhang, Rui; Rosen, Joseph M

2018-05-01

Peripheral nerve injuries impose significant health and economic consequences, yet no surgical repair can deliver a complete recovery of sensory or motor function. Traditional methods of repair are less than ideal: direct coaptation can only be performed when tension-free repair is possible, and transplantation of nerve autograft can cause donor-site morbidity and neuroma formation. Cell-based therapy delivered via nerve conduits has thus been explored as an alternative method of nerve repair in recent years. Stem cells are promising sources of the regenerative core material in a nerve conduit because stem cells are multipotent in function, abundant in supply, and more accessible than the myelinating Schwann cells. Among different types of stem cells, undifferentiated adipose-derived stem cell (uASC), which can be processed from adipose tissue in less than two hours, is a promising yet underexplored cell type. Studies of uASC have emerged in the past decade and have shown that autologous uASCs are non-immunogenic, easy to access, abundant in supply, and efficacious at promoting nerve regeneration. Two theories have been proposed as the primary regenerative mechanisms of uASC: in situ trans-differentiation towards Schwann cells, and secretion of trophic and anti-inflammatory factors. Future studies need to fully elucidate the mechanisms, side effects, and efficacy of uASC-based nerve regeneration so that uASCs can be utilized in clinical settings.

Recent Advances towards the Clinical Application of Stem Cells for Retinal Regeneration

PubMed Central

Becker, Silke; Jayaram, Hari; Limb, G. Astrid

2012-01-01

Retinal degenerative diseases constitute a major cause of irreversible blindness in the world. Stem cell-based therapies offer hope for these patients at risk of or suffering from blindness due to the deterioration of the neural retina. Various sources of stem cells are currently being investigated, ranging from human embryonic stem cells to adult-derived induced pluripotent stem cells as well as human Müller stem cells, with the first clinical trials to investigate the safety and tolerability of human embryonic stem cell-derived retinal pigment epithelium cells having recently commenced. This review aims to summarize the latest advances in the development of stem cell strategies for the replacement of retinal neurons and their supportive cells, the retinal pigment epithelium (RPE) affected by retinal degenerative conditions. Particular emphasis will be given to the advances in stem cell transplantation and the challenges associated with their translation into clinical practice. PMID:24710533

Stem cells to gametes: how far should we go?

PubMed

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.

[Embryos and embryo-like entities: problem of definition in the draft of the Swiss embryonic research law].

PubMed

Bürgin, M T; Bürkli, P

2002-11-01

At the end of May 2002, the draft of the Swiss "Federal Act on Research on Surplus Embryos and Embryonic Stem Cells" (EFG, Embryonic Research Act) reached the pre-legislative consultation stage. Under certain conditions, it would allow research on "surplus" embryos from in-vitro fertilization, and the derivation of embryonic stem cells from surplus embryos for research purposes. The EFG draft defines an embryo as "the developing organism from the point of nuclear fusion until the completion of organ development". New technological developments show that embryo-like entities can also be created without nuclear fusion having taken place. It remains unclear how to treat embryonic entities that don't fall under the draft's narrow definition of an embryo. Expanding this definition would be a welcome improvement.

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.

PubMed

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.

Comparison of defined culture systems for feeder cell free propagation of human embryonic stem cells

PubMed Central

Akopian, Veronika; Beil, Stephen; Benvenisty, Nissim; Brehm, Jennifer; Christie, Megan; Ford, Angela; Fox, Victoria; Gokhale, Paul J.; Healy, Lyn; Holm, Frida; Hovatta, Outi; Knowles, Barbara B.; Ludwig, Tenneille E.; McKay, Ronald D. G.; Miyazaki, Takamichi; Nakatsuji, Norio; Oh, Steve K. W.; Pera, Martin F.; Rossant, Janet; Stacey, Glyn N.; Suemori, Hirofumi

2010-01-01

There are many reports of defined culture systems for the propagation of human embryonic stem cells in the absence of feeder cell support, but no previous study has undertaken a multi-laboratory comparison of these diverse methodologies. In this study, five separate laboratories, each with experience in human embryonic stem cell culture, used a panel of ten embryonic stem cell lines (including WA09 as an index cell line common to all laboratories) to assess eight cell culture methods, with propagation in the presence of Knockout Serum Replacer, FGF-2, and mouse embryonic fibroblast feeder cell layers serving as a positive control. The cultures were assessed for up to ten passages for attachment, death, and differentiated morphology by phase contrast microscopy, for growth by serial cell counts, and for maintenance of stem cell surface marker expression by flow cytometry. Of the eight culture systems, only the control and those based on two commercial media, mTeSR1 and STEMPRO, supported maintenance of most cell lines for ten passages. Cultures grown in the remaining media failed before this point due to lack of attachment, cell death, or overt cell differentiation. Possible explanations for relative success of the commercial formulations in this study, and the lack of success with other formulations from academic groups compared to previously published results, include: the complex combination of growth factors present in the commercial preparations; improved development, manufacture, and quality control in the commercial products; differences in epigenetic adaptation to culture in vitro between different ES cell lines grown in different laboratories. PMID:20186512

MV-NIS Infected Mesenchymal Stem Cells in Treating Patients With Recurrent Ovarian Cancer

ClinicalTrials.gov

2018-01-31

Malignant Ovarian Brenner Tumor; Ovarian Clear Cell Adenocarcinoma; Ovarian Endometrioid Adenocarcinoma; Ovarian Mucinous Adenocarcinoma; Ovarian Seromucinous Carcinoma; Ovarian Serous Adenocarcinoma; Ovarian Transitional Cell Carcinoma; Recurrent Ovarian Carcinoma; Recurrent Primary Peritoneal Carcinoma; Undifferentiated Ovarian Carcinoma

Zika Virus Selectively Kills Aggressive Human Embryonal CNS Tumor Cells In Vitro and In Vivo.

PubMed

Kaid, Carolini; Goulart, Ernesto; Caires-Júnior, Luiz C; Araujo, Bruno H S; Soares-Schanoski, Alessandra; Bueno, Heloisa M S; Telles-Silva, Kayque A; Astray, Renato M; Assoni, Amanda F; Júnior, Antônio F R; Ventini, Daniella C; Puglia, Ana L P; Gomes, Roselane P; Zatz, Mayana; Okamoto, Oswaldo K

2018-06-15

Zika virus (ZIKV) is largely known for causing brain abnormalities due to its ability to infect neural progenitor stem cells during early development. Here, we show that ZIKV is also capable of infecting and destroying stem-like cancer cells from aggressive human embryonal tumors of the central nervous system (CNS). When evaluating the oncolytic properties of Brazilian Zika virus strain (ZIKV BR ) against human breast, prostate, colorectal, and embryonal CNS tumor cell lines, we verified a selective infection of CNS tumor cells followed by massive tumor cell death. ZIKV BR was more efficient in destroying embryonal CNS tumorspheres than normal stem cell neurospheres. A single intracerebroventricular injection of ZIKV BR in BALB/c nude mice bearing orthotopic human embryonal CNS tumor xenografts resulted in a significantly longer survival, decreased tumor burden, fewer metastasis, and complete remission in some animals. Tumor cells closely resembling neural stem cells at the molecular level with activated Wnt signaling were more susceptible to the oncolytic effects of ZIKV BR Furthermore, modulation of Wnt signaling pathway significantly affected ZIKV BR -induced tumor cell death and viral shedding. Altogether, these preclinical findings indicate that ZIKV BR could be an efficient agent to treat aggressive forms of embryonal CNS tumors and could provide mechanistic insights regarding its oncolytic effects. Significance: Brazilian Zika virus strain kills aggressive metastatic forms of human CNS tumors and could be a potential oncolytic agent for cancer therapy. Cancer Res; 78(12); 3363-74. ©2018 AACR . ©2018 American Association for Cancer Research.

A new avenue to the synthesis of GAG-mimicking polymers highly promoting neural differentiation of embryonic stem cells.

PubMed

Wang, Mengmeng; Lyu, Zhonglin; Chen, Gaojian; Wang, Hongwei; Yuan, Yuqi; Ding, Kaiguo; Yu, Qian; Yuan, Lin; Chen, Hong

2015-10-28

A new strategy for the fabrication of glycosaminoglycan (GAG) analogs was proposed by copolymerizing the sulfonated unit and the glyco unit, 'splitted' from the sulfated saccharide building blocks of GAGs. The synthetic polymers can promote cell proliferation and neural differentiation of embryonic stem cells with the effects even better than those of heparin.

75 FR 11185 - Submission for OMB Review; Comment Request; Reinstatement of OMB No. 0925-0601/exp. 02/28/2010...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-10

...; Comment Request; Reinstatement of OMB No. 0925-0601/exp. 02/28/2010, Request for Human Embryonic Stem Cell... period seeking public comment for an information collection entitled ``Request for Human Embryonic Stem Cell Line to be Approved for Use in NIH Funded Research''. In the second paragraph of the notice...

Derivation and characterization of a pig embryonic stem cell-derived exocrine pancreatic cell line

USDA-ARS?s Scientific Manuscript database

The establishment and initial characterization of a pig embryonic stem cell-derived pancreatic cell line, PICM-31, and a colony-cloned derivative cell line, PICM-31A, is described. The cell lines were propagated for several months at split ratios of 1:3 or 1:5 at each passage on STO feeder cells af...

The procurement of cells for the derivation of human embryonic stem cell lines for therapeutic use: recommendations for good practice.

PubMed

Murdoch, Alison; Braude, Peter; Courtney, Aidan; Brison, Daniel; Hunt, Charles; Lawford-Davies, James; Moore, Harry; Stacey, Glyn; Sethe, Sebastian

2012-03-01

The donation of human embryos for the derivation of embryonic stem cell lines that may be used in the development of therapeutic products raises more complex ethical, practical and regulatory problems than the donation of embryos for non-clinical research. This review considers these issues and offers recommendations for good practice.

Neuronal Subtype Generation During Postnatal Olfactory Bulb Neurogenesis

PubMed Central

Angelova, Alexandra; Tiveron, Marie-Catherine; Cremer, Harold; Beclin, Christophe

2018-01-01

In the perinatal and adult forebrain, regionalized neural stem cells lining the ventricular walls produce different types of olfactory bulb interneurons. Although these postnatal stem cells are lineage related to their embryonic counterparts that produce, for example, cortical, septal, and striatal neurons, their output at the level of neuronal phenotype changes dramatically. Tiveron et al. investigated the molecular determinants underlying stem cell regionalization and the gene expression changes inducing the shift from embryonic to adult neuron production. High-resolution gene expression analyses of different lineages revealed that the zinc finger proteins, Zic1 and Zic2, are postnatally induced in the dorsal olfactory bulb neuron lineage. Functional studies demonstrated that these factors confer a GABAergic and calretinin-positive phenotype to neural stem cells while repressing dopaminergic fate. Based on these findings, we discuss the molecular mechanisms that allow acquisition of new traits during the transition from embryonic to adult neurogenesis. We focus on the involvement of epigenetic marks and emphasize why the identification of master transcription factors, that instruct the fate of postnatally generated neurons, can help in deciphering the mechanisms driving fate transition from embryonic to adult neuron production. PMID:29511358

Beyond the permissibility of embryonic and stem cell research: substantive requirements and procedural safeguards.

PubMed

Isasi, Rosario M; Knoppers, Bartha M

2006-10-01

This report provides a comparative analysis of the regulation of embryonic stem cells and cloning research in 50 countries. The development of international stem cell consortia involving the exchange of materials, data and knowledge presumes 'policy know-how' on the varying positions and governing regulations of the various partners; knowledge is essential for the feasibility of such international collaborative projects. Across the spectrum of restrictive-to-liberal policies, requirements regarding the justification for or the setting of substantive limits on (i) embryo use and/or (ii) destruction in research are often present. These goals justify the regulation, the control and even the prohibition of embryonic stem cell and cloning research. Moreover, irrespective of whether a country adopts a restrictive or a liberal approach, there is significant symmetry in both the substantive and the procedural requirements. Procedural safeguards provide another layer of protection and control over the research. In reality, such safeguards may have a greater systemic impact than the substantive requirements. They can be subdivided into three broad categories: (i) safeguards relating to the stage of embryonic development, (ii) safeguards relating to the donors of blastocysts, gametes, embryos and somatic cells and (iii) requirements for research governance.

Redox environment in stem and differentiated cells: A quantitative approach.

PubMed

Lyublinskaya, O G; Ivanova, Ju S; Pugovkina, N A; Kozhukharova, I V; Kovaleva, Z V; Shatrova, A N; Aksenov, N D; Zenin, V V; Kaulin, Yu A; Gamaley, I A; Nikolsky, N N

2017-08-01

Stem cells are believed to maintain a specific intracellular redox status through a combination of enhanced removal capacity and limited production of ROS. In the present study, we challenge this assumption by developing a quantitative approach for the analysis of the pro- and antioxidant ability of human embryonic stem cells in comparison with their differentiated descendants, as well as adult stem and non-stem cells. Our measurements showed that embryonic stem cells are characterized by low ROS level, low rate of extracellular hydrogen peroxide removal and low threshold for peroxide-induced cytotoxicity. However, biochemical normalization of these parameters to cell volume/protein leads to matching of normalized values in stem and differentiated cells and shows that tested in the present study cells (human embryonic stem cells and their fibroblast-like progenies, adult mesenchymal stem cells, lymphocytes, HeLa) maintain similar intracellular redox status. Based on these observations, we propose to use ROS concentration averaged over the cell volume instead of ROS level as a measure of intracellular redox balance. We show that attempts to use ROS level for comparative analysis of redox status of morphologically different cells could lead to false conclusions. Methods for the assessment of ROS concentration based on flow cytometry analysis with the use of H 2 DCFDA dye and HyPer, genetically encoded probe for hydrogen peroxide, are discussed. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Radiation Therapy With or Without Combination Chemotherapy or Pazopanib Hydrochloride Before Surgery in Treating Patients With Newly Diagnosed Non-rhabdomyosarcoma Soft Tissue Sarcomas That Can Be Removed by Surgery

ClinicalTrials.gov

2018-06-20

Adult Fibrosarcoma; Alveolar Soft Part Sarcoma; Angiomatoid Fibrous Histiocytoma; Atypical Fibroxanthoma; Clear Cell Sarcoma of Soft Tissue; Epithelioid Malignant Peripheral Nerve Sheath Tumor; Epithelioid Sarcoma; Extraskeletal Myxoid Chondrosarcoma; Extraskeletal Osteosarcoma; Fibrohistiocytic Neoplasm; Glomus Tumor of the Skin; Inflammatory Myofibroblastic Tumor; Intimal Sarcoma; Leiomyosarcoma; Liposarcoma; Low Grade Fibromyxoid Sarcoma; Low Grade Myofibroblastic Sarcoma; Malignant Cutaneous Granular Cell Tumor; Malignant Peripheral Nerve Sheath Tumor; Malignant Triton Tumor; Mesenchymal Chondrosarcoma; Myxofibrosarcoma; Myxoid Chondrosarcoma; Myxoinflammatory Fibroblastic Sarcoma; Nerve Sheath Neoplasm; PEComa; Pericytic Neoplasm; Plexiform Fibrohistiocytic Tumor; Sclerosing Epithelioid Fibrosarcoma; Stage IB Soft Tissue Sarcoma AJCC v7; Stage IIB Soft Tissue Sarcoma AJCC v7; Stage III Soft Tissue Sarcoma AJCC v7; Stage IV Soft Tissue Sarcoma AJCC v7; Synovial Sarcoma; Undifferentiated (Embryonal) Sarcoma; Undifferentiated High Grade Pleomorphic Sarcoma of Bone

Gelatin-based microcarriers as embryonic stem cell delivery system in bone tissue engineering: an in-vitro study.

PubMed

Tielens, S; Declercq, H; Gorski, T; Lippens, E; Schacht, E; Cornelissen, M

2007-03-01

Mouse embryonic stem cells were cultured on commercially available biodegradable macroporous microcarriers. A culture period of 1-2 weeks was needed to colonize the microcarriers. Embryonic stem cells retained their pluripotency for up to 14 days when cultured in medium supplemented with leukemia inhibitory factor. Replacing this medium by differentiation medium for 2 weeks initiated osteogenic differentiation. Encapsulation of the cell-loaded microcarriers in photopolymerizable polymers (methacrylate-endcapped poly-D,L-lactide-co-caprolactone), triacetin/hydroxyethylmethacrylate (HEMA) as solvent and with/without gelatin as porogen, resulted in a homogeneous distribution of the microcarriers in the polymer. As observed by transmission electron microscopy, viability of the cells was optimal when gelatin was omitted and when using triacetin instead of HEMA.

Organogenesis of heart-vascular system derived from mouse 2 cell stage embryos and from early embryonic stem cells in vitro.

PubMed

Ishiwata, Isamu; Tamagawa, Tomoharu; Tokieda, Yuko; Iguchi, Megumi; Sato, Kahei; Ishikawa, Hiroshi

2003-03-01

Regenerative medical treatment with embryonic stem cells (an ES cell) is a goal for organ transplantation. Structures that are tubular in nature (i.e. blood capillaries) were induced from early embryonic stem (EES) cells in vitro using embryotrophic factor (ETFs). In addition, cardiac muscle cells could be identified as well. However, differentiation of EES cells into a complete cardiovascular system was difficult because 3 germ layer primordial organs are directed embryologically in various ways and it is not possible to guide only cardiovascular organs. Thus, we introduced ETFs after the formation of an embryoid body and were successful in cloning cell clusters that beat, thus deriving only cardiovascular organs. The application of this to the treatment of various cardiovascular diseases is promising.

Generation of a Knockout Mouse Embryonic Stem Cell Line Using a Paired CRISPR/Cas9 Genome Engineering Tool.

PubMed

Wettstein, Rahel; Bodak, Maxime; Ciaudo, Constance

2016-01-01

CRISPR/Cas9, originally discovered as a bacterial immune system, has recently been engineered into the latest tool to successfully introduce site-specific mutations in a variety of different organisms. Composed only of the Cas9 protein as well as one engineered guide RNA for its functionality, this system is much less complex in its setup and easier to handle than other guided nucleases such as Zinc-finger nucleases or TALENs.Here, we describe the simultaneous transfection of two paired CRISPR sgRNAs-Cas9 plasmids, in mouse embryonic stem cells (mESCs), resulting in the knockout of the selected target gene. Together with a four primer-evaluation system, it poses an efficient way to generate new independent knockout mouse embryonic stem cell lines.

Adult bone marrow-derived stem cells for organ regeneration and repair.

PubMed

Tögel, Florian; Westenfelder, Christof

2007-12-01

Stem cells have been recognized as a potential tool for the development of innovative therapeutic strategies. There are in general two types of stem cells, embryonic and adult stem cells. While embryonic stem cell therapy has been riddled with problems of allogeneic rejection and ethical concerns, adult stem cells have long been used in the treatment of hematological malignancies. With the recognition of additional, potentially therapeutic characteristics, bone marrow-derived stem cells have become a tool in regenerative medicine. The bone marrow is an ideal source of stem cells because it is easily accessible and harbors two types of stem cells. Hematopoietic stem cells give rise to all blood cell types and have been shown to exhibit plasticity, while multipotent marrow stromal cells are the source of osteocytes, chondrocytes, and fat cells and have been shown to support and generate a large number of different cell types. This review describes the general characteristics of these stem cell populations and their current and potential future applications in regenerative medicine. 2007 Wiley-Liss, Inc

Scaffolding for Three-Dimensional Embryonic Vasculogenesis

NASA Astrophysics Data System (ADS)

Kraehenbuehl, Thomas P.; Aday, Sezin; Ferreira, Lino S.

Biomaterial scaffolds have great potential to support efficient vascular differentiation of embryonic stem cells. Vascular cell fate-specific biochemical and biophysical cues have been identified and incorporated into three-dimensional (3D) biomaterials to efficiently direct embryonic vasculogenesis. The resulting vascular-like tissue can be used for regenerative medicine applications, further elucidation of biophysical and biochemical cues governing vasculogenesis, and drug discovery. In this chapter, we give an overview on the following: (1) developmental cues for directed differentiation of human embryonic stem cells (hESCs) into vascular cells, (2) 3D vascular differentiation in embryoid bodies (EBs), (3) preparation of 3D scaffolds for the vascular differentiation of hESCs, and (4) the most significant studies combining scaffolding and hESCs for development of vascular-like tissue.

'New embryos' - new challenges for the ethics of stem cell research.

PubMed

Holm, Søren

2008-01-01

Among the many ethical issues raised by human embryonic stem cell research (in the following all references to 'stem cells' should be read as references to human embryonic stem cells), two have gained specific prominence: (1) whether stem cell research is ethically problematic because it entails the destruction of human embryos and (2) what kind of control embryo donors should have over the stem cell lines derived from their embryos. In the present paper, I will analyse how these two issues are engaged by various attempts to derive stem cells from anomalous embryos (e.g. embryos in cleavage arrest, embryos not implanted following pre-implantation genetic diagnosis or embryos created by altered nuclear transfer) or in ways that are claimed to be non-destructive for the embryo (e.g. blastocyst or blastomere biopsy). Copyright 2008 S. Karger AG, Basel.

Identifying Tumor Progenitor Cells | Center for Cancer Research

Cancer.gov

All cells within a tumor are not identical. In fact, only a small subset appears to be capable of actually generating the tumor. These tumor-initiating cells tend to resemble normal stem cells, which have the unique ability to give rise to differentiated cells while simultaneously producing additional undifferentiated stem cells. Most chemotherapeutics affect the bulk of a tumor but spare the stem-like cells, allowing the tumor to re-grow once chemotherapy is stopped. If, however, the cancer-initiating cells could be successfully targeted, cancer recurrence could be prevented.

Human embryonic stem cell lines: socio-legal concerns and therapeutic promise.

PubMed

McLaren, Anne

2002-10-01

Stem cell lines would be very valuable for the repair of diseased or damaged organs. Stem cells derived from adult tissues raise few ethical problems, and would not be rejected if derived from the patient. They show considerable plasticity and might be appropriate for some clinical conditions, but they tend not to grow well in culture. Stem cells derived from the early human embryo proliferate indefinitely in culture and can give rise to many different tissues, but their derivation requires destruction of the embryo, which is not ethically acceptable in some countries. Other countries allow strictly regulated destructive research on human embryos, usually those that have been produced for infertile couples in infertility clinics. Embryos that are no longer required for the couple's own reproductive project could be donated for research rather than just discarded. Different approaches are being developed to avoid immunological rejection of embryonic stem cells used for therapy. Derivation of embryonic stem cell lines by somatic cell nuclear transfer ('cloning') from the patients themselves might be one possible approach, but is unlikely to be used in routine clinical practice if more cost-effective methods are available.

miR-137 forms a regulatory loop with nuclear receptor TLX and LSD1 in neural stem cells

PubMed Central

Sun, GuoQiang; Ye, Peng; Murai, Kiyohito; Lang, Ming-Fei; Li, Shengxiu; Zhang, Heying; Li, Wendong; Fu, Chelsea; Yin, Jason; Wang, Allen; Ma, Xiaoxiao; Shi, Yanhong

2012-01-01

miR-137 is a brain-enriched microRNA. Its role in neural development remains unknown. Here we show that miR-137 plays an essential role in controlling embryonic neural stem cell fate determination. miR-137 negatively regulates cell proliferation and accelerates neural differentiation of embryonic neural stem cells. In addition, we show that histone demethylase LSD1, a transcriptional co-repressor of nuclear receptor TLX, is a downstream target of miR-137. In utero electroporation of miR-137 in embryonic mouse brains led to premature differentiation and outward migration of the transfected cells. Introducing a LSD1 expression vector lacking the miR-137 recognition site rescued miR-137-induced precocious differentiation. Furthermore, we demonstrate that TLX, an essential regulator of neural stem cell self-renewal, represses the expression of miR-137 by recruiting LSD1 to the genomic regions of miR-137. Thus, miR-137 forms a feedback regulatory loop with TLX and LSD1 to control the dynamics between neural stem cell proliferation and differentiation during neural development. PMID:22068596

An Alternative Method for Long-Term Culture of Chicken Embryonic Stem Cell In Vitro.

PubMed

Zhang, Li; Wu, Yenan; Li, Xiang; Wei, Shao; Xing, Yiming; Lian, Zhengxing; Han, Hongbing

2018-01-01

Chicken embryonic stem cells (cESCs) obtained from stage X embryos provide a novel model for the study of avian embryonic development. A new way to maintain cESCs for a long period in vitro still remains unexplored. We found that the cESCs showed stem cell-like properties in vitro for a long term with the support of DF-1 feeder and basic culture medium supplemented with human basic fibroblast growth factor (hbFGF), mouse stem cell factor (mSCF), and human leukemia inhibitory factor (hLIF). During the long culture period, the cESCs showed typical ES cell morphology and expressed primitive stem cell markers with a relatively stable proliferation rate and high telomerase activity. These cells also exhibited the capability to differentiate into cardiac myocytes, smooth muscle cells, neural cells, osteoblast, and adipocyte in vitro . Chimera chickens were produced by cESCs cultured for 25 passages with this new culture system. The experiments showed that DF-1 was the optimal feeder and hbFGF was an important factor for maintaining the pluripotency of cESCs in vitro .

Identification of stem cells from human umbilical cord blood with embryonic and hematopoietic characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao Yong; Wang Honglan; Mazzone, Theodore

2006-08-01

We identified stem cells from the umbilical cord blood, designated cord blood-stem cells (CB-SC). CB-SC displayed important embryonic stem (ES) cell characteristics including expression of ES-cell-specific molecular markers including transcription factors OCT-4 and Nanog, along with stage-specific embryonic antigen (SSEA)-3 and SSEA-4. CB-SC also expressed hematopoietic cell antigens including CD9, CD45 and CD117, but were negative for CD34. CB-SC displayed very low immunogenicity as indicated by expression of a very low level of major histocompatibility complex (MHC) antigens and failure to stimulate the proliferation of allogeneic lymphocytes. CB-SC could give rise to cells with endothelial-like and neuronal-like characteristics in vitro,more » as demonstrated by expression of lineage-associated markers. Notably, CB-SC could be stimulated to differentiate into functional insulin-producing cells in vivo and eliminated hyperglycemia after transplantation into a streptozotocin-induced diabetic mouse model. These findings may have significant potential to advance stem-cell-based therapeutics.« less

Induction of pluripotent stem cells transplantation therapy for ischemic stroke.

PubMed

Jiang, Mei; Lv, Lei; Ji, Haifeng; Yang, Xuelian; Zhu, Wei; Cai, Liying; Gu, Xiaju; Chai, Changfeng; Huang, Shu; Sun, Jian; Dong, Qiang

2011-08-01

Stroke can cause permanent neurological damage, complications, and even death. However, there is no treatment exists to restore its lost function. Human embryonic stems transplantation therapy was a novel and potential therapeutic approach for stroke. However, as we have seen, the ethical controversy pertains to embryonic stem cell research. Human induced pluripotent stem cells (iPSCs) are the latest generation of stem cells that may be a solution to the controversy of using embryonic cells. In our study, we generated iPSCs from adult human fibroblasts by introduction of four defined transcription factors (Oct4, Sox2, Nanog, and Lin-28). And then, we investigated the efficacy of iPSCs transplantation therapy for stroke on the animal models of middle cerebral artery occlusion. Surprisingly, we found that transplanted iPSCs migrated to injured brain areas, and differentiated into neuron-like cells successfully. After 4-16 days iPSCs grafting, sensorimotor function of rats has been improved significantly. In one word, we may prove that iPSCs therapy in stroke to be an effective form of treatment.

Inhibition of IKK/NF-κB Signaling Enhances Differentiation of Mesenchymal Stromal Cells from Human Embryonic Stem Cells.

PubMed

Deng, Peng; Zhou, Chenchen; Alvarez, Ruth; Hong, Christine; Wang, Cun-Yu

2016-04-12

Embryonic stem cell-derived mesenchymal stromal cells (MSCs; also known as mesenchymal stem cells) represent a promising source for bone regenerative medicine. Despite remarkable advances in stem cell biology, the molecular mechanism regulating differentiation of human embryonic stem cells (hESCs) into MSCs remains poorly understood. Here, we report that inhibition of IκB kinase (IKK)/nuclear factor kappa B (NF-κB) signaling enhances differentiation of hESCs into MSCs by expediting the loss of pluripotent markers and increasing the expression of MSC surface markers. In addition, a significantly higher quantity of MSCs was produced from hESCs with IKK/NF-κB suppression. These isolated MSCs displayed evident multipotency with capacity to terminally differentiate into osteoblasts, chondrocytes, and adipocytes in vitro and to form bone in vivo. Collectively, our data provide important insights into the role of NF-κB in mesenchymal lineage specification during hESC differentiation, suggesting that IKK inhibitors could be utilized as an adjuvant in generating MSCs for cell-mediated therapies. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Deciphering the Epigenetic Code in Embryonic and Dental Pulp Stem Cells

PubMed Central

Bayarsaihan, Dashzeveg

2016-01-01

A close cooperation between chromatin states, transcriptional modulation, and epigenetic modifications is required for establishing appropriate regulatory circuits underlying self-renewal and differentiation of adult and embryonic stem cells. A growing body of research has established that the epigenome topology provides a structural framework for engaging genes in the non-random chromosomal interactions to orchestrate complex processes such as cell-matrix interactions, cell adhesion and cell migration during lineage commitment. Over the past few years, the functional dissection of the epigenetic landscape has become increasingly important for understanding gene expression dynamics in stem cells naturally found in most tissues. Adult stem cells of the human dental pulp hold great promise for tissue engineering, particularly in the skeletal and tooth regenerative medicine. It is therefore likely that progress towards pulp regeneration will have a substantial impact on the clinical research. This review summarizes the current state of knowledge regarding epigenetic cues that have evolved to regulate the pluripotent differentiation potential of embryonic stem cells and the lineage determination of developing dental pulp progenitors. PMID:28018144

Embryonic stem cells in scaffold-free three-dimensional cell culture: osteogenic differentiation and bone generation.

PubMed

Handschel, Jörg; Naujoks, Christian; Depprich, Rita; Lammers, Lydia; Kübler, Norbert; Meyer, Ulrich; Wiesmann, Hans-Peter

2011-07-14

Extracorporeal formation of mineralized bone-like tissue is still an unsolved challenge in tissue engineering. Embryonic stem cells may open up new therapeutic options for the future and should be an interesting model for the analysis of fetal organogenesis. Here we describe a technique for culturing embryonic stem cells (ESCs) in the absence of artificial scaffolds which generated mineralized miromasses. Embryonic stem cells were harvested and osteogenic differentiation was stimulated by the addition of dexamethasone, ascorbic acid, and ß-glycerolphosphate (DAG). After three days of cultivation microspheres were formed. These spherical three-dimensional cell units showed a peripheral zone consisting of densely packed cell layers surrounded by minerals that were embedded in the extracellular matrix. Alizarine red staining confirmed evidence of mineralization after 10 days of DAG stimulation in the stimulated but not in the control group. Transmission electron microscopy demonstrated scorching crystallites and collagenous fibrils as early indication of bone formation. These extracellular structures resembled hydroxyl apatite-like crystals as demonstrated by distinct diffraction patterns using electron diffraction analysis. The micromass culture technique is an appropriate model to form three-dimensional bone-like micro-units without the need for an underlying scaffold. Further studies will have to show whether the technique is applicable also to pluripotent stem cells of different origin. © 2011 Handschel et al; licensee BioMed Central Ltd.

Survival of priceless cells: active and passive protection of embryonic stem cells against immune destruction.

PubMed

Utermöhlen, Olaf; Krönke, Martin

2007-06-15

This review focuses on our current knowledge of the mechanisms employed by embryonic stem (ES) cells to avoid destruction by cell-mediated immune responses. Recently, ES cells have been found to shield themselves against cytotoxic effector cells by expressing CD95L and serine protease inhibitor SPI-6 mediating apoptosis of the cytotoxic cells and inactivation of granzyme B, respectively. These findings are discussed in view of their implications for using ES cell-derived transplants in regenerative medicine as well as for our understanding of early embryonic stages during invasion and implantation.

Maintaining embryonic stem cell pluripotency with Wnt signaling.

PubMed

Sokol, Sergei Y

2011-10-01

Wnt signaling pathways control lineage specification in vertebrate embryos and regulate pluripotency in embryonic stem (ES) cells, but how the balance between progenitor self-renewal and differentiation is achieved during axis specification and tissue patterning remains highly controversial. The context- and stage-specific effects of the different Wnt pathways produce complex and sometimes opposite outcomes that help to generate embryonic cell diversity. Although the results of recent studies of the Wnt/β-catenin pathway in ES cells appear to be surprising and controversial, they converge on the same conserved mechanism that leads to the inactivation of TCF3-mediated repression.

Behavior of stem cells under outer-space microgravity and ground-based microgravity simulation.

PubMed

Zhang, Cui; Li, Liang; Chen, Jianling; Wang, Jinfu

2015-06-01

With rapid development of space engineering, research on life sciences in space is being conducted extensively, especially cellular and molecular studies on space medicine. Stem cells, undifferentiated cells that can differentiate into specialized cells, are considered a key resource for regenerative medicine. Research on stem cells under conditions of microgravity during a space flight or a ground-based simulation has generated several excellent findings. To help readers understand the effects of outer space and ground-based simulation conditions on stem cells, we reviewed recent studies on the effects of microgravity (as an obvious environmental factor in space) on morphology, proliferation, migration, and differentiation of stem cells. © 2015 International Federation for Cell Biology.

In vivo imaging: shining a light on stem cells in the living animal.

PubMed

Nguyen, Phong Dang; Currie, Peter David

2018-03-28

Stem cells are undifferentiated cells that play crucial roles during development, growth and regeneration. Traditionally, these cells have been primarily characterised by histology, cell sorting, cell culture and ex vivo methods. However, as stem cells interact in a complex environment within specific tissue niches, there has been increasing interest in examining their in vivo behaviours, particularly in response to injury. Advances in imaging technologies and genetic tools have converged to enable unprecedented access to the endogenous stem cell niche. In this Spotlight article, we highlight how in vivo imaging can probe a range of biological processes that relate to stem cell activity, behaviour and control. © 2018. Published by The Company of Biologists Ltd.

In vitro fertilization, the Nobel Prize, and human embryonic stem cells.

PubMed

Gearhart, John; Coutifaris, Christos

2011-01-07

Robert Edwards was awarded the 2010 Nobel Prize in Physiology or Medicine for the development of human in vitro fertilization. His work not only provided the means to overcome many forms of infertility, but it also enabled research on early stages of human embryos and the derivation of human embryonic stem cells. Copyright © 2011 Elsevier Inc. All rights reserved.

High School Students Debate the Use of Embryonic Stem Cells: The Influence of Context on Decision-Making

ERIC Educational Resources Information Center

Molinatti, Gregoire; Girault, Yves; Hammond, Constance

2010-01-01

The present study analyzes decision-making and argumentation by high school students in a debate situation on a socioscientific issue, the use of embryonic stem cells in research and therapy. We tested the influence on the debates of two different contexts. Adolescent students at the high school level in the same grade (mean age 16.4 years) from…

Leukemia inhibitory factor (LIF) enhances MAP2 + and HUC/D + neurons and influences neurite extension during differentiation of neural progenitors derived from human embryonic stem cells.

EPA Science Inventory

Leukemia Inhibitory Factor (L1F), a member of the Interleukin 6 cytokine family, has a role in differentiation of Human Neural Progenitor (hNP) cells in vitro. hNP cells, derived from Human Embryonic Stem (hES) cells, have an unlimited capacity for self-renewal in monolayer cultu...

Stem cells: Balancing resistance and sensitivity to DNA damage

PubMed Central

Liu, Julia C.; Lerou, Paul H.; Lahav, Galit

2015-01-01

Embryonic stem cells are known to be very sensitive to DNA damage and undergo rapid apoptosis even after low damage doses. In contrast, adult stem cells show variable sensitivity to damage. Here we describe the multiple pathways that have been proposed to affect the sensitivity of stem cells to damage, including proximity to the apoptotic threshold (mitochondrial priming) and the p53 signaling pathway, through activation of transcription or direct interaction with pro apoptotic proteins in the cytoplasm. We also discuss which cellular factors might connect mitochondrial priming with pluripotency and the potential therapeutic advances that can be achieved by better understanding the molecular mechanisms leading to sensitivity or resistance of embryonic or adult stem cells from different tissues. PMID:24721782

"Nutrient-sensing" and self-renewal: O-GlcNAc in a new role.

PubMed

Sharma, Nikita S; Saluja, Ashok K; Banerjee, Sulagna

2018-06-01

Whether embryonic, hematopoietic or cancer stem cells, this metabolic reprogramming is dependent on the nutrient-status and bioenergetic pathways that is influenced by the micro-environmental niches like hypoxia. Thus, the microenvironment plays a vital role in determining the stem cell fate by inducing metabolic reprogramming. Under the influence of the microenvironment, like hypoxia, the stem cells have increased glucose and glutamine uptake which result in activation of hexosamine biosynthesis pathway (HBP) and increased O-GlcNAc Transferase (OGT). The current review is focused on understanding how HBP, a nutrient-sensing pathway (that leads to increased OGT activity) is instrumental in regulating self-renewal not only in embryonic and hematopoietic stem cells (ESC/HSC) but also in cancer stem cells.

Will embryonic stem cells change health policy?

PubMed

Sage, William M

2010-01-01

Embryonic stem cells are actively debated in political and public policy arenas. However, the connections between stem cell innovation and overall health care policy are seldom elucidated. As with many controversial aspects of medical care, the stem cell debate bridges to a variety of social conversations beyond abortion. Some issues, such as translational medicine, commercialization, patient and public safety, health care spending, physician practice, and access to insurance and health care services, are core health policy concerns. Other issues, such as economic development, technologic progress, fiscal politics, and tort reform, are only indirectly related to the health care system but are frequently seen through a health care lens. These connections will help determine whether the stem cell debate reaches a resolution, and what that resolution might be.

Repair of Torn Avascular Meniscal Cartilage Using Undifferentiated Autologous Mesenchymal Stem Cells: From In Vitro Optimization to a First-in-Human Study.

PubMed

Whitehouse, Michael R; Howells, Nicholas R; Parry, Michael C; Austin, Eric; Kafienah, Wael; Brady, Kyla; Goodship, Allen E; Eldridge, Jonathan D; Blom, Ashley W; Hollander, Anthony P

2017-04-01

Meniscal cartilage tears are common and predispose to osteoarthritis (OA). Most occur in the avascular portion of the meniscus where current repair techniques usually fail. We described previously the use of undifferentiated autologous mesenchymal stem cells (MSCs) seeded onto a collagen scaffold (MSC/collagen-scaffold) to integrate meniscal tissues in vitro. Our objective was to translate this method into a cell therapy for patients with torn meniscus, with the long-term goal of delaying or preventing the onset of OA. After in vitro optimization, we tested an ovine-MSC/collagen-scaffold in a sheep meniscal cartilage tear model with promising results after 13 weeks, although repair was not sustained over 6 months. We then conducted a single center, prospective, open-label first-in-human safety study of patients with an avascular meniscal tear. Autologous MSCs were isolated from an iliac crest bone marrow biopsy, expanded and seeded into the collagen scaffold. The resulting human-MSC/collagen-scaffold implant was placed into the meniscal tear prior to repair with vertical mattress sutures and the patients were followed for 2 years. Five patients were treated and there was significant clinical improvement on repeated measures analysis. Three were asymptomatic at 24 months with no magnetic resonance imaging evidence of recurrent tear and clinical improvement in knee function scores. Two required subsequent meniscectomy due to retear or nonhealing of the meniscal tear at approximately 15 months after implantation. No other adverse events occurred. We conclude that undifferentiated MSCs could provide a safe way to augment avascular meniscal repair in some patients. Registration: EU Clinical Trials Register, 2010-024162-22. Stem Cells Translational Medicine 2017;6:1237-1248. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

New perspectives in human stem cell therapeutic research.

PubMed

Trounson, Alan

2009-06-11

Human stem cells are in evaluation in clinical stem cell trials, primarily as autologous bone marrow studies, autologous and allogenic mesenchymal stem cell trials, and some allogenic neural stem cell transplantation projects. Safety and efficacy are being addressed for a number of disease state applications. There is considerable data supporting safety of bone marrow and mesenchymal stem cell transplants but the efficacy data are variable and of mixed benefit. Mechanisms of action of many of these cells are unknown and this raises the concern of unpredictable results in the future. Nevertheless there is considerable optimism that immune suppression and anti-inflammatory properties of mesenchymal stem cells will be of benefit for many conditions such as graft versus host disease, solid organ transplants and pulmonary fibrosis. Where bone marrow and mesenchymal stem cells are being studied for heart disease, stroke and other neurodegenerative disorders, again progress is mixed and mostly without significant benefit. However, correction of multiple sclerosis, at least in the short term is encouraging. Clinical trials on the use of embryonic stem cell derivatives for spinal injury and macular degeneration are beginning and a raft of other clinical trials can be expected soon, for example, the use of neural stem cells for killing inoperable glioma and embryonic stem cells for regenerating beta islet cells for diabetes. The change in attitude to embryonic stem cell research with the incoming Obama administration heralds a new co-operative environment for study and evaluation of stem cell therapies. The Californian stem cell initiative (California Institute for Regenerative Medicine) has engendered global collaboration for this new medicine that will now also be supported by the US Federal Government. The active participation of governments, academia, biotechnology, pharmaceutical companies, and private investment is a powerful consortium for advances in health.

The Warburg effect: persistence of stem-cell metabolism in cancers as a failure of differentiation.

PubMed

Riester, M; Xu, Q; Moreira, A; Zheng, J; Michor, F; Downey, R J

2018-01-01

Two recent observations regarding the Warburg effect are that (i) the metabolism of stem cells is constitutive (aerobic) glycolysis while normal cellular differentiation involves a transition to oxidative phosphorylation and (ii) the degree of glucose uptake of a malignancy as imaged by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is associated with histologic measures of tumor differentiation. Combining these observations, we hypothesized that the high levels of glucose uptake observed in poorly differentiated cancers may reflect persistence of the glycolytic metabolism of stem cells in malignant cells that fail to fully differentiate. Tumor glucose uptake was measured by FDG-PET in 552 patients with histologically diverse cancers. We used normal mixture modeling to explore FDG-PET standardized uptake value (SUV) distributions and tested for associations between glucose uptake and histological differentiation, risk of lymph node metastasis, and survival. Using RNA-seq data, we carried out pathway and transcription factor analyses to compare tumors with high and low levels of glucose uptake. We found that well-differentiated tumors had low FDG uptake, while moderately and poorly differentiated tumors had higher uptake. The distribution of SUV for each histology was bimodal, with a low peak around SUV 2-5 and a high peak at SUV 8-14. The cancers in the two modes were clinically distinct in terms of the risk of nodal metastases and death. Carbohydrate metabolism and the pentose-related pathway were elevated in the poorly differentiated/high SUV clusters. Embryonic stem cell-related signatures were activated in poorly differentiated/high SUV clusters. Our findings support the hypothesis that the biological basis for the Warburg effect is a persistence of stem cell metabolism (i.e. aerobic glycolysis) in cancers as a failure to transition from glycolysis-utilizing undifferentiated cells to oxidative phosphorylation-utilizing differentiated cells. We found that cancers cluster along the differentiation pathway into two groups, utilizing either glycolysis or oxidative phosphorylation. Our results have implications for multiple areas of clinical oncology. © The Author 2017. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Generation of Functional Thyroid Tissue Using 3D-Based Culture of Embryonic Stem Cells.

PubMed

Antonica, Francesco; Kasprzyk, Dominika Figini; Schiavo, Andrea Alex; Romitti, Mírian; Costagliola, Sabine

2017-01-01

During the last decade three-dimensional (3D) cultures of pluripotent stem cells have been intensively used to understand morphogenesis and molecular signaling important for the embryonic development of many tissues. In addition, pluripotent stem cells have been shown to be a valid tool for the in vitro modeling of several congenital or chronic human diseases, opening new possibilities to study their physiopathology without using animal models. Even more interestingly, 3D culture has proved to be a powerful and versatile tool to successfully generate functional tissues ex vivo. Using similar approaches, we here describe a protocol for the generation of functional thyroid tissue using mouse embryonic stem cells and give all the details and references for its characterization and analysis both in vitro and in vivo. This model is a valid approach to study the expression and the function of genes involved in the correct morphogenesis of thyroid gland, to elucidate the mechanisms of production and secretion of thyroid hormones and to test anti-thyroid drugs.

An immunohistochemical study of neuropeptides and neuronal cytoskeletal proteins in the neuroepithelial component of a spontaneous murine ovarian teratoma. Primitive neuroepithelium displays immunoreactivity for neuropeptides and neuron-associated beta-tubulin isotype.

PubMed Central

Caccamo, D. V.; Herman, M. M.; Frankfurter, A.; Katsetos, C. D.; Collins, V. P.; Rubinstein, L. J.

1989-01-01

Approximately one third of the female mice of the LTXBO strain develop spontaneous ovarian teratomas. These tumors contain a large neuroepithelial component, which includes primitive neural structures resembling embryonic neural tubes (medulloepithelial rosettes), ependymoblastic and ependymal rosettes, neuroblasts, mature ganglionic neurons, myelinated neurites, and astrocytes. The purpose of this study was to characterize these tumors according to the immunohistochemical location of some well-characterized trophic and regulatory neuropeptides and neurotransmitters, several neuronal-associated cytoskeletal proteins, and other proteins indicative of neuronal and glial differentiation. Medulloepithelial rosettes showed focal serotonin-like, opioid peptide-like and gamma-amino butyric acid-like immunoreactivity, and displayed immunostaining for the neuron-associated class III beta-tubulin isotype. The mature ganglion cells were also immunoreactive for these markers, and, in addition, for somatostatin, cholecystokinin, bombesin, glucagon, vasoactive intestinal peptide, and neuropeptide Y. Mature ganglion cells were also immunoreactive for proteins associated with the neuronal cytoskeleton (including microtubule-associated proteins, MAP2 and tau, and higher molecular weight phosphorylated and non-phosphorylated neurofilament subunits), neuron-specific enolase, and synaptophysin. Undifferentiated stem cells, ependymoblastic and ependymal rosettes, and astroglia all stained with a monoclonal antibody that recognizes all mammalian beta-tubulin isotypes, but did not react with antibodies to neuronal-associated cytoskeletal proteins or neuropeptides. Neuropeptide-like immunoreactivity and demonstration of the class III beta-tubulin isotype indicate early neuronal commitment in neoplastic primitive neuroepithelium. These patterns of immunoreactivity closely follow those encountered in the normal neurocytogenesis of the mammalian and avian forebrain, and increase the precision with which the early stages of progressive neuroepithelial differentiation can be analyzed in human embryonal tumors of the CNS. Images Figure 1 Figure 2 Figure 3 PMID:2817080

Use of deep neural network ensembles to identify embryonic-fetal transition markers: repression of COX7A1 in embryonic and cancer cells

PubMed Central

West, Michael D.; Labat, Ivan; Sternberg, Hal; Larocca, Dana; Nasonkin, Igor; Chapman, Karen B.; Singh, Ratnesh; Makarev, Eugene; Aliper, Alex; Kazennov, Andrey; Alekseenko, Andrey; Shuvalov, Nikolai; Cheskidova, Evgenia; Alekseev, Aleksandr; Artemov, Artem; Putin, Evgeny; Mamoshina, Polina; Pryanichnikov, Nikita; Larocca, Jacob; Copeland, Karen; Izumchenko, Evgeny; Korzinkin, Mikhail; Zhavoronkov, Alex

2018-01-01

Here we present the application of deep neural network (DNN) ensembles trained on transcriptomic data to identify the novel markers associated with the mammalian embryonic-fetal transition (EFT). Molecular markers of this process could provide important insights into regulatory mechanisms of normal development, epimorphic tissue regeneration and cancer. Subsequent analysis of the most significant genes behind the DNNs classifier on an independent dataset of adult-derived and human embryonic stem cell (hESC)-derived progenitor cell lines led to the identification of COX7A1 gene as a potential EFT marker. COX7A1, encoding a cytochrome C oxidase subunit, was up-regulated in post-EFT murine and human cells including adult stem cells, but was not expressed in pre-EFT pluripotent embryonic stem cells or their in vitro-derived progeny. COX7A1 expression level was observed to be undetectable or low in multiple sarcoma and carcinoma cell lines as compared to normal controls. The knockout of the gene in mice led to a marked glycolytic shift reminiscent of the Warburg effect that occurs in cancer cells. The DNN approach facilitated the elucidation of a potentially new biomarker of cancer and pre-EFT cells, the embryo-onco phenotype, which may potentially be used as a target for controlling the embryonic-fetal transition. PMID:29487692

Use of deep neural network ensembles to identify embryonic-fetal transition markers: repression of COX7A1 in embryonic and cancer cells.

PubMed

West, Michael D; Labat, Ivan; Sternberg, Hal; Larocca, Dana; Nasonkin, Igor; Chapman, Karen B; Singh, Ratnesh; Makarev, Eugene; Aliper, Alex; Kazennov, Andrey; Alekseenko, Andrey; Shuvalov, Nikolai; Cheskidova, Evgenia; Alekseev, Aleksandr; Artemov, Artem; Putin, Evgeny; Mamoshina, Polina; Pryanichnikov, Nikita; Larocca, Jacob; Copeland, Karen; Izumchenko, Evgeny; Korzinkin, Mikhail; Zhavoronkov, Alex

2018-01-30

Here we present the application of deep neural network (DNN) ensembles trained on transcriptomic data to identify the novel markers associated with the mammalian embryonic-fetal transition (EFT). Molecular markers of this process could provide important insights into regulatory mechanisms of normal development, epimorphic tissue regeneration and cancer. Subsequent analysis of the most significant genes behind the DNNs classifier on an independent dataset of adult-derived and human embryonic stem cell (hESC)-derived progenitor cell lines led to the identification of COX7A1 gene as a potential EFT marker. COX7A1 , encoding a cytochrome C oxidase subunit, was up-regulated in post-EFT murine and human cells including adult stem cells, but was not expressed in pre-EFT pluripotent embryonic stem cells or their in vitro -derived progeny. COX7A1 expression level was observed to be undetectable or low in multiple sarcoma and carcinoma cell lines as compared to normal controls. The knockout of the gene in mice led to a marked glycolytic shift reminiscent of the Warburg effect that occurs in cancer cells. The DNN approach facilitated the elucidation of a potentially new biomarker of cancer and pre-EFT cells, the embryo-onco phenotype, which may potentially be used as a target for controlling the embryonic-fetal transition.

Molecular cloning and functional analysis of ESGP, an embryonic stem cell and germ cell specific protein.

PubMed

Chen, Yan-Mei; Du, Zhong-Wei; Yao, Zhen

2005-12-01

Several putative Oct-4 downstream genes from mouse embryonic stem (ES) cells have been identified using the suppression-subtractive hybridization method. In this study, one of the novel genes encoding an ES cell and germ cell specific protein (ESGP) was cloned by rapid amplification of cDNA ends. ESGP contains 801 bp encoding an 84 amino acid small protein and has no significant homology to any known genes. There is a signal peptide at the N-terminal of ESGP protein as predicted by SeqWeb (GCG) (SeqWeb version 2.0.2, http://gcg.biosino.org:8080/). The result of immunofluorescence assay suggested that ESGP might encode a secretory protein. The expression pattern of ESGP is consistent with the expression of Oct-4 during embryonic development. ESGP protein was detected in fertilized oocyte, from 3.5 day postcoital (dpc) blastocyst to 17.5 dpc embryo, and was only detected in testis and ovary tissues in adult. In vitro, ESGP was only expressed in pluripotent cell lines, such as embryonic stem cells, embryonic caoma cells and embryonic germ cells, but not in their differentiated progenies. Despite its specific expression, forced expression of ESGP is not indispensable for the effect of Oct-4 on ES cell self-renewal, and does not affect the differentiation to three germ layers.

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

PubMed

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.