This work was in part supported by grants to W.D. from National Institutes of Health (RO1 NS059043 and RO1 ES015988), National Multiple Sclerosis Society, Roche Foundation for Anemia Research, Feldstein Medical Foundation, and the Shriners Hospitals for Children.
We would like to thank Dr. David Pleasure and Jennifer Plane for suggestions. We declare no competing interests related to this article.

Detailed procedures of generating oligodendrocyte precursor cells (OPCs) from GFP-Olig2 mouse embryonic stem cells (mESCs):
<ol>
 <li>Mouse ES cell line GFP-Olig2 (G-Olig2), is purchased from the American Type Culture Collection (ATCC). The mESCs are routinely passaged every 3 days onto an irradiated mouse embryonic fibroblast (MEF) feeder layer. The MEF cells are plated into 0.1% gelatin-coated six-well tissue culture plate at least one day before passaging the ESCs. The mESC culture medium is Dulbecco's modified Eagle's medium (DMEM) (GIBCO) supplemented with 20% fetal bovine serum (GIBCO), 2 mM L-glutamine, 1 mM sodium pyruvate, 0.1 mM &beta;-mercaptoethanol/, 1% nonessential amino acids (NEAA), and 1,000 U/ml leukemia inhibitory factor.</li>
 <li>mES colonies are trypsinized (TrypLE, 5 min, 37&deg;C) into single cells and suspended in knockout serum replacement (KSR) medium, then the cells are transferred to a Costar ultra-low attachment six-well plate (Corning) at a cell density of 50,000 cells/cm2. In these conditions, mESCs form embryoid bodies (EBs). KSR medium consists of -minimal essential medium (-MEM) supplemented with 20% KSR, 1 mM sodium pyruvate, 1% NEAA, and 0.1 mM &beta;-mercaptoethanol/.</li>
 <li>From day 4 to day 7, retinoic acid (RA, 0.2 M) and purmorphamine (Pur, 1 M) are included as shown in Fig. 1A in KSR or N2 medium. The N2 medium is -MEM containing 1X N2 supplement, 1 mM sodium pyruvate, 1% NEAA, and 0.1 mM &beta;-mercaptoethanol/. The medium is changed everyday.</li>
 <li>At day 8, EBs are disaggregated using TrypLE (5min, 37&deg;C) and plated on 0.01% polyornithine-coated dishes in OPC medium that consists of N2 medium and fibroblast growth factor-2 (FGF-2, 20 ng/ml). The medium is changed every two days.</li>
 <li>The cells are trypsinized (TrypLE, 3 min, 37&deg;C) and replated approximately every week when they become confluent. At day 30, over 80% of the cells show GFP/Olig2 expression and are NG2-positive, characteristic of OPCs.</li>
 <li>To generate spiking OPCs, the BacMam Na+ channel kit is used to introduce Nav1.2 subunit into these mESC-derived OPCs. The BacMam reagent (1 ml, component A) is mixed with PBS to a final volume of 5 ml. Then, the mixed BacMam reagent is added into mESC-derived OPCs culture in a 60 mm culture dish (at 50-70% confluence) prior to rinsing with PBS. After 2 hr incubation, the mixed BacMam reagent is removed and replaced with OPC medium supplemented with 1X enhancer. The enhancer is the component B reconstituted in DMSO (component C). Next, after additional 2-hr incubation the medium with enhancer is removed and replaced with complete OPC medium. The cells are assayed 24 hrs later.</li>
</ol>
Representative Results:
Following the differentiation protocol shown in Fig. 1A, G-Olig2 mESCs were initially suspended in KSR medium and for 4 days to form embryoid bodies (EBs) (Fig. 1B). Then, we sequentially treated the EBs with RA and Pur. The EBs did not show any GFP fluorescence at Day 4 and expressed strong GFP fluorescence at D8 (Fig. 1B). At this time point, the EBs were trypsinized and plated in N2 medium supplemented with growth factors FGF-2. After further culture for 22 days (D30), the percentage of GFP+ cell reached 80.3 &plusmn; 0.6 % according to our flow cytometry results. As shown in Fig. 1C, GFP+ cells overlapped with NG2 staining consistently (96.4 &plusmn; 1.3% of GFP positive cells were NG2 positive, and 94.8 &plusmn; 1.5% of NG2 positive cells were GFP positive). Thus, these cells express GFP/Olig2 and NG2, defining them as OPCs.
The mESC-derived OPCs (76 cells) failed to fire action potentials upon depolarization (Fig. 2A). After transducing with a baculovirus carrying the Nav1.2 subunit, these mESC-derived OPCs (94.1%, 16 of 17 cells) could be classified as spiking (Fig. 2B).
<img alt="Figure 1" src="/files/ftp_upload/1960/1960fig1.jpg" /> 
 Figure 1. Differentiation of GOlig-mESC into OPCs. (A) Scheme showing the protocol of the embryoid body (EB)-based and small molecule-driven differentiation. At D8, the EBs were disaggregated and plated. The cells were passaged once per week when they became confluent. (B) D8, but not D4 EBs, showed GFP expression. (C) Immunostaining of NG2 (red) was consistent with GFP (green) expression at D30. DAPI (blue) was used to identify the nuclei. Scale bar: 20 mm.
<img alt="Figure 2" src="/files/ftp_upload/1960/1960fig2.jpg" /> 
 Figure 2. Generation of spiking OPCs from nonspiking mESC-derived OPCs by virus-mediated Nav channel expression.&nbsp; (A) The membrane potential was held at -60 mV and mESC-derived OPCs failed to fire action potentials, even when the cell was depolarized to 0 mV. (B) An example of mESC-derived OPC firing action potential (highlighted in red) after the viral transduction.

<ol>
	<li>Xian, H., Gottlieb, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dividing+Olig2-expressing+progenitor+cells+derived+from+ES+cells.">Dividing Olig2-expressing progenitor cells derived from ES cells.</a> Glia. 47 (1), 88-101 (2004).</li><li>Clair, A., Gottlieb, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+subset+of+ES-cell-derived+neural+cells+marked+by+gene+targeting.">A subset of ES-cell-derived neural cells marked by gene targeting.</a> Stem Cells. 21 (1), 41-49 (2003).</li><li>Evans, M. J., Kaufman, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishment+in+culture+of+pluripotential+cells+from+mouse+embryos.">Establishment in culture of pluripotential cells from mouse embryos.</a> Nature. 292, 154-156 (1981).</li><li>Thomson, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Embryonic+stem+cell+lines+derived+from+human+blastocysts.">Embryonic stem cell lines derived from human blastocysts.</a> Science. 282, 1145-1147 (1998).</li><li>Shin, S., Xue, H., Mattson, M. P., Rao, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stage-dependent+Olig2+expression+in+motor+neurons+and+oligodendrocytes+differentiated+from+embryonic+stem+cells.">Stage-dependent Olig2 expression in motor neurons and oligodendrocytes differentiated from embryonic stem cells.</a> Stem Cells Dev. 16, 131-141 (2007).</li><li>Billon, N., Jolicoeur, C., Ying, Q. L., Smith, A., Raff, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Normal+timing+of+oligodendrocyte+development+from+genetically+engineered,+lineage-selectable+mouse+ES+cells.">Normal timing of oligodendrocyte development from genetically engineered, lineage-selectable mouse ES cells.</a> J Cell Sci. 115, 3657-3665 (2002).</li><li>Nishiyama, A., Lin, X. H., Giese, N., Heldin, C. H., Stallcup, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Co-localization+of+NG2+proteoglycan+and+PDGF+alpha-receptor+on+O2A+progenitor+cells+in+the+developing+rat+brain.">Co-localization of NG2 proteoglycan and PDGF alpha-receptor on O2A progenitor cells in the developing rat brain.</a> J Neurosci Res. 43, 299-314 (1996).</li><li>Ligon, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+NG2+neural+progenitor+cells+requires+Olig+gene+function.">Development of NG2 neural progenitor cells requires Olig gene function.</a> Proc Natl Acad Sci U S A. 103, 7853-7858 (2006).</li><li>Dawson, M. R., Polito, A., Levine, J. M., Reynolds, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NG2-expressing+glial+progenitor+cells:+an+abundant+and+widespread+population+of+cycling+cells+in+the+adult+rat+CNS.">NG2-expressing glial progenitor cells: an abundant and widespread population of cycling cells in the adult rat CNS.</a> Mol Cell Neurosci. 24, 476-488 (2003).</li><li>Chittajallu, R., Aguirre, A., Gallo, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NG2-positive+cells+in+the+mouse+white+and+grey+matter+display+distinct+physiological+properties.">NG2-positive cells in the mouse white and grey matter display distinct physiological properties.</a> J Physiol. 561, 109-122 (2004).</li><li>Karadottir, R., Hamilton, N. B., Bakiri, Y., Attwell, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spiking+and+nonspiking+classes+of+oligodendrocyte+precursor+glia+in+CNS+white+matter.">Spiking and nonspiking classes of oligodendrocyte precursor glia in CNS white matter.</a> Nat Neurosci. 11, 450-456 (2008).</li></ol>

No conflicts of interest declared.

Embryonic stem cells (ESCs), isolated from a blastocyst embryo, can differentiate into all cell lineages of the organism 3, 4, providing an in vitro model system for studying early mammalian development, including oligodendrocyte specification. mESCs have been shown to differentiate into oligodendrocyte precursor cells (OPCs) with the treatment of sonic hedgehog (Shh) 5. Moreover, the Shh-induced OPC differentiation from mESCs retains the correct timing observed in embryonic development 6. Hence, the nature of in vitro OPC differentiation from mESCs is considered to be consistent with what has been learned from in vivo development. Here, using the small molecules RA and the Shh agonist Pur, we successfully differentiated the G-Olig2 mESCs into GFP+Olig2+NG2+ OPCs with high efficiency. OPCs, characterized by the expression of the proteoglycan NG2 7 and the helix-loop-helix transcription factor Olig2 8, generate oligodendrocytes in the developing and mature CNS, where they comprise a significant percentage (~ 5%) of the total cells and are the main proliferating cell type 9. For nearly two decades researchers have demonstrated NaV channels are expressed in a subpopulation of OPCs and can be activated upon depolarization 10, 11. Moreover, a recent striking observation9 was that in in situ rat CNS white matter, OPCs (~ 50%) generated action potentials when depolarized depending upon the expression of voltage-gated sodium (NaV) channels, and thus could be subdivided into spiking and nonspiking subpopulations. However, the functions of these spiking properties are still largely unknown. We found that, electrophysiologically, the mESC-derived OPCs differentiated with the Shh-dependent protocol, were not the same as the in situ brain OPCs. After introducing subunit NaV1.2, these silent mESC-derived OPCs were capable of spiking. Thus, the spiking/nonspiking mESC-derived OPCs and differentiation protocol described here may facilitate (1) studying the functional differences between spiking and nonspiking OPCs, (2) screening new factors that could promote sodium channel expression in the mESC-derived OPCs, (3) developing and optimizing the differentiation protocol of OPCs from human ESC or induced pluripotent stem cells (iPSCs).

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<td>MEFs</td>
<td>&nbsp;</td>
<td>GlobalStem </td>
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<td>TrypLE Express</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>12604</td>
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<td>Retinoic acid</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>R-2625</td>
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<td>Purmorphamine</td>
<td>&nbsp;</td>
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differentiation of embryonic stem cells into oligodendrocyte precursors

Oligodendrocytes are the myelinating cells of the central nervous system. For regenerative cell therapy in demyelinating diseases, there is significant interest in deriving a pure population of lineage-committed oligodendrocyte precursor cells (OPCs) for transplantation. OPCs are characterized by the activity of the transcription factor Olig2 and surface expression of a proteoglycan NG2. Using the GFP-Olig2 (G-Olig2) mouse embryonic stem cell (mESC) reporter line, we optimized conditions for the differentiation of mESCs into GFP+Olig2+NG2+ OPCs. In our protocol, we first describe the generation of embryoid bodies (EBs) from mESCs. Second, we describe treatment of mESC-derived EBs with small molecules: (1) retinoic acid (RA) and (2) a sonic hedgehog (Shh) agonist purmorphamine (Pur) under defined culture conditions to direct EB differentiation into the oligodendroglial lineage. By this approach, OPCs can be obtained with high efficiency (&gt;80%) in a time period of 30 days. Cells derived from mESCs in this protocol are phenotypically similar to OPCs derived from primary tissue culture. The mESC-derived OPCs do not show the spiking property described for a subpopulation of brain OPCs in situ. To study this electrophysiological property, we describe the generation of spiking mESC-derived OPCs by ectopically expressing NaV1.2 subunit. The spiking and nonspiking cells obtained from this protocol will help advance functional studies on the two subpopulations of OPCs.

Watch this Scientific Journal Video about Differentiation of Embryonic Stem Cells into Oligodendrocyte Precursors at JoVE.com

Differentiation of Embryonic Stem Cells into Oligodendrocyte Precursors

We describe a small molecule-based protocol for differentiation of mouse embryonic stem cells into oligodendrocyte precursor cells (OPCs). This protocol generates Olig2+NG2+ OPCs with high efficiency by 30 days of differentiation. We also describe a method to generate "spiking" OPCs that can fire action potentials.

Oligodendrocytes are the myelinating cells of the central nervous system. For regenerative cell therapy in demyelinating diseases, there is significant ...

differentiation-embryonic-stem-cells-into-oligodendrocyte

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15.3K Views.  School of Medicine, University of California, Davis. We describe a small molecule-based protocol for differentiation of mouse embryonic stem cells into oligodendrocyte precursor cells (OPCs). This protocol generates Olig2+NG2+ OPCs with high efficiency by 30 days of differentiation. We also describe a method to generate "spiking" OPCs that can fire action potentials.

Video: Differentiation of Embryonic Stem Cells into Oligodendrocyte Precursors

Propagation of Human Embryonic Stem (ES) Cells

Propagation of Human Embryonic Stem ES Cells

Yeah, so I'm Lauren Deon. I'm in charge of the Human Amgen stem cell co facility at MGH. Yeah, so I'm Lauren, I'm in charge of the Human AM stem cell co facility at MGH.So I've been working with human Amgen stem cells for years now since I was a postdoc in George De Lab before, from four, four years. And so right now we have two cell lines, H one and H nine, which are both from Y cell. And so the way we are expanding or maintaining these cells in culture is by, at least the way we are splitting these cells is by using collagenous.So what I usually do is for the first few passage after throwing the cells, I use a technical, the picking colonies. So in this case, I can check under the microscope which colonies are good and differentiate and nice shape, and I will collect only these colonies and I will cut them in few pieces and put them back in, in a fresh flat. And the, the colonies that look kind of differentiate it are just left them alone.The other way to pass the cells is by using trypsin. So I don't use this technique here. I think collagenase is a little bit safer because human being stem cells don't like to be individualized or they don't like to be alone.So if you do trypsin, if you use trypsin for a little bit too long, if you use it for like three to four minutes, which is the way we use strips in for other type of cells, human stem cells will be individualized and most of them will die or just differentiate or will not attach to the myth. So the idea is you have to keep the cells as clumps. You don't want them to be alone in the in, in the flask.So using collagenase, the advantage is to keep cells as plants. Using chipsy, you just select for cells that will survive this very, very harsh process of g opsonization. So these cells are usually very highly proliferative.So you get, you can adapt your cells to this tripsin process. The problem is that you have cells that they behave differently, they go much faster. And one risk is that you can get some commercial abnormality to, to this, to this very high division process.So you say that ization can cause selection of cells in culture for most proliferative cells.Right. More ative and probably also higher survival rates than other cells. So after proliferation, basically culture after proliferation in tripsin, after several passages become a different culture, these different properties.So it's, it's hard to figure out if they are exactly identical. If you do the test, the usual test, let's say you check markers, regular markers of end differentiated cells like OC four, nano one 60 SC four C, C3, all this molecule might still be expressed. If you do TER formation, this cells might still differentiate and be formed like al like normal cells.If you look at the karyotype, you might have some abnormality, but you might still have a normal karyotype. The, the, the selective advantage might be due to just a mutation that you cannot see by doing a karyotype. So the fact that they grow much faster is by itself I think a little bit worser.And if we want to use these cells for transplantation at some point, I would definitely not use this type of cells.Okay. So would you like to tell me what are the main technical problems with using this technique for, for passages of cells? So using S, yes.It's just a little bit longer and also it's, since the cells are not going as fast, it's just much longer to get a high number of cells to do some experiment. So it's just less convenient I would say. Would you like to tell me about few words about the goals of your experiment?How do you use CS cells? Okay, so my main project here is to get endothelial cells from human AB stem cells. And the idea is to be able to make blood.And we are working a lot with tissue bioengineering labs and one of their goal is to make tissue in vitro. But one of the limitation to this is the lack of blood vessels going through this tissues. So if we can bring endothelial cells or put endothelial cells in this tissue, we would have better growth of this tissue.So the idea few sources of cells are known for endothelial cells like cold blood or pressure blood, but it would be interesting to have another source of cells like human years. And the advantage is since human years can be expanded and most infinitely, you could modify these cells, make some inducible system and be able to use it. Then in your final product, your material cells, in this case.

Rozprzestrzenianie się człowieka zarodkowych komórek macierzystych (ES) Cells

Culture of Mouse Neural Stem Cell Precursors

Primary neural stem cell cultures are useful for studying the mechanisms underlying central nervous system development. Stem cell research will increase our understanding of the nervous system and may allow us to develop treatments for currently incurable brain diseases and injuries. In addition, stem cells should be used for stem cell research aimed at the detailed study of mechanisms of neural differentiation and transdifferentiation and the genetic and environmental signals that direct the specialization of the cells into particular cell types.  This video demonstrates a technique used to disaggregate cells from the embryonic day 12.5 mouse dorsal forebrain. The dissection procedure includes harvesting E12.5 mouse embryos from the uterus, removing the "skin" with fine dissecting forceps and finally isolating pieces of cerebral cortex. Following the dissection, the tissue is digested and mechanically dissociated. The resuspended dissociated cells are then cultured in "stem cell" media that favors growth of neural stem cells.

This video describes the method used for isolation of neuroprecursors from the developing cortex of embryonic mice. The procedure for removing embryos from the uterus, dissecting the cortical tissue, and digesting the isolated cerebral cortex is shown.

Primary neural stem cell cultures are useful for studying the mechanisms underlying central nervous system development. Stem cell research will increase ...

Derivation of Hematopoietic Stem Cells from Murine Embryonic Stem Cells

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are derived from the blastocyst of the early embryo and are pluripotent in differentiative ability.  Their vast differentiative potential has made them the focus of much research centered on deducing how to coax them to generate clinically useful cell types.  The successful derivation of hematopoietic stem cells (HSC) from mouse ESC has recently been accomplished and can be visualized in this video protocol.  HSC, arguably the most clinically exploited cell population, are used to treat a myriad of hematopoietic malignancies and disorders.  However, many patients that might benefit from HSC therapy lack access to suitable donors.  ESC could provide an alternative source of HSC for these patients.  The following protocol establishes a baseline from which ESC-HSC can be studied and inform efforts to isolate HSC from human ESC.  In this protocol, ESC are differentiated as embryoid bodies (EBs) for 6 days in commercially available serum pre-screened for optimal hematopoietic differentiation.  EBs are then dissociated and infected with retroviral HoxB4.  Infected EB-derived cells are plated on OP9 stroma, a bone marrow stromal cell line derived from the calvaria of  M-CSF-/- mice, and co-cultured in the presence of hematopoiesis promoting cytokines for ten days.  During this co-culture, the infected cells expand greatly, resulting in the generation a heterogeneous pool of 100s of millions of cells.  These cells can then be used to rescue and reconstitute lethally irradiated mice.

This protocol details the derivation of transplantable hematopoietic stem cells from mouse embryonic stem cells (ESC) and their subsequent injection into lethally irradiated recipient mice. Briefly, ESC are differentiated as embryoid bodies, which are then infected with retroviral HoxB4 and co-cultured with OP9 stromal cells and hematopoietic cytokines.

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are ...

Derivation of Human Embryonic Stem Cells by Immunosurgery

The ability of human embryonic stem cells to self-renew and differentiate into all cell types of 
the body suggests that they hold great promise for both medical applications and as a research 
tool for addressing fundamental questions in development and disease. Here, we provide a 
concise, step-by-step protocol for the derivation of human embryonic stem cells from embryos 
by immunosurgical isolation of the inner cell mass. 


The ability of human embryonic stem cells to self-renew and differentiate into all cell types of 
the body suggests that they hold great promise for both medical applications and as a research 
tool for addressing fundamental questions in development and disease. Here, we provide a 
concise, step-by-step protocol for the derivation of human embryonic stem cells from embryos 
by immunosurgical isolation of the inner cell mass.

The ability of human embryonic stem cells to self-renew and differentiate into all cell types of 
the body suggests that they hold great promise for both ...

Chromatin Immunoprecipitation from Human Embryonic Stem Cells

The functional and structural complexity of the myriad of cells in metazoan organisms arises from a small number of stem cells. Stem cells are characterized by two fundamental properties: self-renewal and multipotency that allows a stem cell to differentiate into virtually any cell type 1. The progression stem cell to differentiated cell is characterized by loss of multipotency, structural and morphological changes and the hierarchic activity of transcription factors and signaling molecules, whose activities establish and maintain cell-type specific gene expression patterns. At the molecular level, cell differentiation involves dynamic changes of the structure and composition of chromatin and the detection of those dynamic changes can provide valuable insights into the functional features of stem cells and the cell differentiation process 2,3. Chromatin is a highly compacted DNA-protein complex that forms when cells package chromosomal DNA with proteins, mainly histones 4. Stemcellness and cell differentiation has been correlated with the presence of specific arrays of regulatory proteins such as epigenetic factors, histone variants, and transcription factors 2,3,5.
 Chromatin immunoprecipitation (ChIP) provides a valuable method to monitor the presence of RNA, proteins, and protein modifications in chromatin 6,7. The comparison of chromatin from different cell types can elucidate dynamic changes in protein-chromatin associations that occur during cell differentiation.
Chromatin immunoprecipitation involves the purification of in vivo cross-linked chromatin. The isolated chromatin is reduced to smaller fragments by enzymatic digestion or mechanical force. Chromatin fragments are precipitated using specific antibodies to target proteins or protein and DNA modifications. The precipitated DNA or RNA is purified and used as a template for PCR or DNA microarray based assays. Prerequisites for a successful ChIP are high quality antibodies to the desired antigen and the availability of chromatin from control cells that do not express the target molecule. ChIP can correlate the presence of proteins, protein and RNA modifications, and RNA with specific target DNA, and depending on the choice of outread tool, detects the association of target molecules at specific target genes or in the context of an entire genome. The comparison of the distribution of proteins in the chromatin of differentiating cells can elucidate the dynamic changes of chromatin composition that coincide with the progression of cells along a cell lineage.

The differentiation of ESC coincides with cell-type specific changes in the structure and composition of chromatin. The detection of those changes provides valuable insights into the mechanisms that define stemcellness and cell differentiation. Chromatin immunoprecipitation (ChIP) represents a valuable method to dissect the molecular mechanisms underlying stem cell differentiation.

The functional and structural complexity of the myriad of cells in metazoan organisms arises from a small number of stem cells. Stem cells are ...

In vitro Differentiation of Mouse Embryonic Stem (mES) Cells Using the Hanging Drop Method

Stem cells have the remarkable potential to develop into many different cell types. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, This promising of science is leading scientists to investigate the possibility of cell-based therapies to treat disease.

When culture in suspension without antidifferentiation factors, embryonic stem cells spontaneously differentiate and form three-dimensional multicellular aggregates. These cell aggregates are called embryoid bodies(EB). Hanging drop culture is a widely used EB formation induction method. The rounded bottom of hanging drop allows the aggregation of ES cells which can provide mES cells a good environment for forming EBs. The number of ES cells aggregatied in a hanging drop can be controlled by varying the number of cells in the initial cell suspension to be hung as a drop from the lid of Petri dish. Using this method we can reproducibly form homogeneous EBs from a predetermined number of ES cells. 

In vitro Differentiation of Mouse Embryonic Stem mES Cells Using the Hanging Drop Method

This video demonstrates how to conduct in vitro differentiation of mouse embryonic stem cells to embryoid bodies using the hanging drop method.

Stem cells have the remarkable potential to develop into many different cell types. When a stem cell divides, each new cell has the potential to either ...

Freezing and Thawing Human Embryonic Stem Cells

Since James Thomson et al developed a technique in 1998 to isolate and grow hES in culture, freezing cells for later use and thawing and expanding cells from a frozen stock have become important procedures performed in routine hES cell culture. Since hES cells are very sensitive to the stresses of freezing and thawing, special care must taken. Here we demonstrate the proper technique for rapidly thawing hES cells from liquid nitrogen stocks, plating them on mouse embryonic feeder cells, and slowly freezing them for long-term storage.

Since James Thomson et al developed a technique in 1998 to isolate and grow hES in culture, freezing cells for later use and thawing and expanding cells from a frozen stock have become important procedures performed in routine hES cell culture. Since hES cells are very sensitive to the stresses of freezing and thawing, special care must taken. Here we demonstrate the proper technique for rapidly thawing hES cells from liquid nitrogen stocks, plating them on mouse embryonic feeder cells, and slowly freezing them for long-term storage.

Since James Thomson et al developed a technique in 1998 to isolate and grow hES in culture, freezing cells for later use and thawing and expanding cells ...

Efficient Derivation of Human Cardiac Precursors and Cardiomyocytes from Pluripotent Human Embryonic Stem Cells with Small Molecule Induction

To date, the lack of a suitable human cardiac cell source has been the major setback in regenerating the human myocardium, either by cell-based transplantation or by cardiac tissue engineering1-3. Cardiomyocytes become terminally-differentiated soon after birth and lose their ability to proliferate. There is no evidence that stem/progenitor cells derived from other sources, such as the bone marrow or the cord blood, are able to give rise to the contractile heart muscle cells following transplantation into the heart1-3. The need to regenerate or repair the damaged heart muscle has not been met by adult stem cell therapy, either endogenous or via cell delivery1-3. The genetically stable human embryonic stem cells (hESCs) have unlimited expansion ability and unrestricted plasticity, proffering a pluripotent reservoir for in vitro derivation of large supplies of human somatic cells that are restricted to the lineage in need of repair and regeneration4,5. Due to the prevalence of cardiovascular disease worldwide and acute shortage of donor organs, there is intense interest in developing hESC-based therapies as an alternative approach. However, how to channel the wide differentiation potential of pluripotent hESCs efficiently and predictably to a desired phenotype has been a major challenge for both developmental study and clinical translation. Conventional approaches rely on multi-lineage inclination of pluripotent cells through spontaneous germ layer differentiation, resulting in inefficient and uncontrollable lineage-commitment that is often followed by phenotypic heterogeneity and instability, hence, a high risk of tumorigenicity6-8 (see a schematic in Fig. 1A). In addition, undefined foreign/animal biological supplements and/or feeders that have typically been used for the isolation, expansion, and differentiation of hESCs may make direct use of such cell-specialized grafts in patients problematic9-11. To overcome these obstacles, we have resolved the elements of a defined culture system necessary and sufficient for sustaining the epiblast pluripotence of hESCs, serving as a platform for de novo derivation of clinically-suitable hESCs and effectively directing such hESCs uniformly towards clinically-relevant lineages by small molecules12 (see a schematic in Fig. 1B). After screening a variety of small molecules and growth factors, we found that such defined conditions rendered nicotinamide (NAM) sufficient to induce the specification of cardiomesoderm direct from pluripotent hESCs that further progressed to cardioblasts that generated human beating cardiomyocytes with high efficiency (Fig. 2). We defined conditions for induction of cardioblasts direct from pluripotent hESCs without an intervening multi-lineage embryoid body stage, enabling well-controlled efficient derivation of a large supply of human cardiac cells across the spectrum of developmental stages for cell-based therapeutics.

We have established a protocol for induction of cardioblasts direct from pluripotent human embryonic stem cells maintained under defined conditions with small molecules, which enables derivation of a large supply of human cardiac progenitors and functional cardiomyocytes for cardiovascular repair.

To date, the lack of a suitable human cardiac cell source has been the major setback in regenerating the human myocardium, either by cell-based ...

Efficient Differentiation of Mouse Embryonic Stem Cells into Motor Neurons

Direct differentiation of embryonic stem (ES) cells into functional motor neurons represents a promising resource to study disease mechanisms, to screen new drug compounds, and to develop new therapies for motor neuron diseases such as spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS). Many current protocols use a combination of retinoic acid (RA) and sonic hedgehog (Shh) to differentiate mouse embryonic stem (mES) cells into motor neurons1-4. However, the differentiation efficiency of mES cells into motor neurons has only met with moderate success. We have developed a two-step differentiation protocol5 that significantly improves the differentiation efficiency compared with currently established protocols. The first step is to enhance the neuralization process by adding Noggin and fibroblast growth factors (FGFs). Noggin is a bone morphogenetic protein (BMP) antagonist and is implicated in neural induction according to the default model of neurogenesis and results in the formation of anterior neural patterning6. FGF signaling acts synergistically with Noggin in inducing neural tissue formation by promoting a posterior neural identity7-9. In this step, mES cells were primed with Noggin, bFGF, and FGF-8 for two days to promote differentiation towards neural lineages. The second step is to induce motor neuron specification. Noggin/FGFs exposed mES cells were incubated with RA and a Shh agonist, Smoothened agonist (SAG), for another 5 days to facilitate motor neuron generation. To monitor the differentiation of mESs into motor neurons, we used an ES cell line derived from a transgenic mouse expressing eGFP under the control of the motor neuron specific promoter Hb91. Using this robust protocol, we achieved 51&plusmn;0.8% of differentiation efficiency (n = 3; p &lt; 0.01, Student's t-test)5. Results from immunofluorescent staining showed that GFP+ cells express the motor neuron specific markers, Islet-1 and choline acetyltransferase (ChAT). Our two-step differentiation protocol provides an efficient way to differentiate mES cells into spinal motor neurons.

We developed a new protocol to improve efficiency of in vitro differentiation of mouse embryonic stem cells into motor neurons. The differentiated ES cells acquired motor neurons features as evidenced by expression of neuronal and motor neuron markers using immunohistochemical techniques.

Direct differentiation of embryonic stem (ES) cells into functional  motor neurons represents a promising resource to study disease mechanisms, to  screen ...

Differentiation of Newborn Mouse Skin Derived Stem Cells into Germ-like Cells In vitro

Studying germ cell formation and differentiation has traditionally been very difficult due to low cell numbers and their location deep within developing embryos. The availability of a "closed" in vitro based system could prove invaluable for our understanding of gametogenesis. The formation of oocyte-like cells (OLCs) from somatic stem cells, isolated from newborn mouse skin, has been demonstrated and can be visualized in this video protocol. The resulting OLCs express various markers consistent with oocytes such as Oct4 , Vasa , Bmp15, and Scp3. However, they remain unable to undergo maturation or fertilization due to a failure to complete meiosis. This protocol will provide a system that is useful for studying the early stage formation and differentiation of germ cells into more mature gametes. During early differentiation the number of cells expressing Oct4 (potential germ-like cells) reaches ~5%, however currently the formation of OLCs remains relatively inefficient. The protocol is relatively straight forward though special care should be taken to ensure the starting cell population is healthy and at an early passage.

Differentiation of Newborn Mouse Skin Derived Stem Cells into Germ-like Cells In vitro

In recent years the formation of germ cells using in vitro culture methods has been demonstrated using several different types of somatic stem cells. This article will visually present the differentiation of newborn mouse derived stem cells to early oocyte-like cells.

Studying  germ cell formation and differentiation has traditionally been very difficult  due to low cell numbers and their location deep within developing ...