We would like to thank members of the Lee lab for valuable discussions on the manuscript. Work in the Lee lab was supported by grants from Robertson Investigator Award of New York Stem Cell Foundation and from Maryland Stem Cell Research Fund (TEDCO).

1. Preparation of a 96-well Plate
<ol>
	<li>Mix 1 &#956;l of Single Cell DNase1 to 9 &#956;l Single Cell Lysis Solution.</li>
	<li>Put the 10 &#956;l mixed solution in each well of 96-well PCR plate.</li>
</ol>
2. Detaching hESCs for FACS Purification
<ol>
	<li>Detach OCT4::EGFP ES cell line from the 60 mm dish with 1 ml Accutase for 20 min, at 37 &#176;C, which were neutralized with human ES media.</li>
	<li>Prepare cell population in 1 ml FACS buffer and adjust the cell to 1 x 106 cells/ml.</li>
	<li>Pass the cell sample through a 35 &#956;m cell strainer cap tube.</li>
	<li>Store the tube in ice before cell sorting.</li>
</ol>
3. Lysis of FACS-purified Single Cell in Each Well of the 96-well Plate
<ol>
	<li>Sort the sample for EGFP positive cells on a cell sorter with a trained operator. Put the single cell into Single Cell Lysis/DNase1 solution in 96-well PCR plate. If necessary, the 96-well plate with sample can be stored in a -80 &#176;C deep freezer less than one month.</li>
	<li>Incubate samples 5 min at RT for cell lysis.</li>
	<li>Add 1 &#956;l of Stop Solution to stop lysis reaction.</li>
	<li>Incubate 2 min at RT.</li>
</ol>
4. Reverse Transcription
<ol>
	<li>Add to each a 0.5 &#956;l aliquot of 20 &#956;M SMA-T15, SMA-A.</li>
	<li>Add 4 &#956;l 5X buffer, 2 &#956;l DTT, 1 &#956;l Reverse Transcriptase, and 1 &#956;l dNTP to each well.</li>
	<li>Perform reverse transcription in a thermal cycler.
	<ol>
		<li>Set the thermal program at 42 &#176;C &#215; 90 min and inactivate Reverse Transcriptase at 85 &#176;C &#215; 5 min.</li>
	</ol>
	</li>
</ol>
5. Amplification
<ol>
	<li>Add 4 &#956;l of ExoSAP-IT reagent to each reverse transcribed sample.
	<ol>
		<li>Incubate samples at 37 &#176;C for 15 min and 80 &#176;C for 15 min to inactivate the ExoSAP-IT reagent.</li>
	</ol>
	</li>
	<li>Prepare PCR reaction mix with SMA-p2 (2 nM)</li>
	<li>Add 10 &#956;l of PCR reaction mix to each reverse transcribed sample.</li>
	<li>Perform the amplification, consisting of 20 cycles of denaturation (94 &#176;C for 30 sec), annealing (57 &#176;C for 30 sec), and extension (68 &#176;C for 10 min).</li>
</ol>
6. qRT-PCR Performance
<ol>
	<li>Add 10 &#956;l of 2X SYBR Green PCR Master Mix, 1 &#956;l amplified cDNA, 2 nM primers, and 7 &#956;l water to each well.
	<ol>
		<li>Set the program followed by 95 &#176;C for 3 sec, 60 &#176;C for 30 sec x 40 cycles.</li>
	</ol>
	</li>
	<li>Perform in duplicate for technical errors.</li>
</ol>

<ol>
	<li>Miyanari, Y., Torres-Padilla, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+ground-state+pluripotency+by+allelic+regulation+of+Nanog.">Control of ground-state pluripotency by allelic regulation of Nanog.</a> Nature. 483, 470-473 (2012).</li><li>Leitch, H. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Embryonic+germ+cells+from+mice+and+rats+exhibit+properties+consistent+with+a+generic+pluripotent+ground+state.">Embryonic germ cells from mice and rats exhibit properties consistent with a generic pluripotent ground state.</a> Development. 137, 2279-2287 (2010).</li><li>Ramskold, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Full-length+mRNA-Seq+from+single-cell+levels+of+RNA+and+individual+circulating+tumor+cells.">Full-length mRNA-Seq from single-cell levels of RNA and individual circulating tumor cells.</a> Nat Biotechnol. 30, 777-782 (2012).</li><li>Stewart, M. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clonal+isolation+of+hESCs+reveals+heterogeneity+within+the+pluripotent+stem+cell+compartment.">Clonal isolation of hESCs reveals heterogeneity within the pluripotent stem cell compartment.</a> Nat Methods. 3, 807-815 (2006).</li><li>O'Malley, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-resolution+analysis+with+novel+cell-surface+markers+identifies+routes+to+iPS+cells.">High-resolution analysis with novel cell-surface markers identifies routes to iPS cells.</a> Nature. 499, 88-91 (2013).</li><li>Nichols, J., Smith, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Naive+and+primed+pluripotent+states.">Naive and primed pluripotent states.</a> Cell Stem Cell. 4, 487-492 (2009).</li><li>Kim, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=miR-371-3+expression+predicts+neural+differentiation+propensity+in+human+pluripotent+stem+cells.">miR-371-3 expression predicts neural differentiation propensity in human pluripotent stem cells.</a> Cell Stem Cell. 8, 695-706 (2011).</li><li>Mortazavi, A., Williams, B. A., Mccue, K., Schaeffer, L., Wold, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mapping+and+quantifying+mammalian+transcriptomes+by+RNA-Seq.">Mapping and quantifying mammalian transcriptomes by RNA-Seq.</a> Nat Methods. 5, 621-628 (2008).</li><li>Pan, Q., Shai, O., Lee, L. J., Frey, J., Blencowe, B. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deep+surveying+of+alternative+splicing+complexity+in+the+human+transcriptome+by+high-throughput+sequencing.">Deep surveying of alternative splicing complexity in the human transcriptome by high-throughput sequencing.</a> Nat Genet. 40, 1413-1415 (2008).</li><li>Wang, E. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alternative+isoform+regulation+in+human+tissue+transcriptomes.">Alternative isoform regulation in human tissue transcriptomes.</a> Nature. 456, 470-476 (2008).</li><li>Hockemeyer, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+engineering+of+human+pluripotent+cells+using+TALE+nucleases.">Genetic engineering of human pluripotent cells using TALE nucleases.</a> Nat Biotechnol. 29, 731-734 (2011).</li><li>Lee, G., Chambers, S. M., Tomishima, M. J., Studer, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Derivation+of+neural+crest+cells+from+human+pluripotent+stem+cells.">Derivation of neural crest cells from human pluripotent stem cells.</a> Nat Protoc. 5, 688-701 (2010).</li><li>Zhu, Y. Y., Machleder, E. M., Chenchik, A., Li, R., Siebert, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reverse+transcriptase+template+switching:+A+SMART+(TM)+approach+for+full-length+cDNA+library+construction.">Reverse transcriptase template switching: A SMART (TM) approach for full-length cDNA library construction.</a> Biotechniques. 30, 892-897 (2001).</li><li>Pan, X. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+methods+for+full-length+RNA+sequencing+for+low+quantities+of+cells+and+single+cells.">Two methods for full-length RNA sequencing for low quantities of cells and single cells.</a> P Natl Acad Sci USA. 110, 594-599 (2013).</li><li>Tang, F. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA-Seq+analysis+to+capture+the+transcriptome+landscape+of+a+single+cell.">RNA-Seq analysis to capture the transcriptome landscape of a single cell.</a> Nat Protoc. 5, 516-535 (2010).</li></ol>

The authors have nothing to disclose.

Single cell gene profiling could be a major tool to predict functionality of a single cell or an entire population. Due to technical limitation, whole gene profiling analysis has been restricted to population averages. Variations in gene expression patterns and levels between individual cells and the subpopulations have been proposed to cause erroneous interpretation. Such diverse cellular aspects can be found in hESCs and their heterogeneity causes subtly different ability for maintaining pluripotency and fate specifica...

Most higher eukaryote populations are heterogeneous thus with analysis of pooled population, it is often difficult to interpret their cellular features. Individual cells within a population may be subtly different, and these differences can have important consequences for the property and function of the entire population1,2. Especially, human embryonic stem cells (hESCs) are known to be heterogeneous, which causes different levels of pluripotency and diverse potentials to lineage specification in delicately distinctive ways3,4. For example, different cell surface antigens can be used to categorize undifferentiated pluripotent stem cells,5 and the Austin Smith group proposed different levels of pluripotency in mouse embryonic stem cells, based on their morphology, differentiation propensity and dependency of signaling pathway6. This phenomenon was hypothesized in human embryonic stem cells7. Whereas the overall studies were performed among different stem cell lines, not individual single stem cells, it could be very intriguing to analyze different levels of pluripotency at the single cell level, which potentially affects their differentiation capacities toward all somatic cell lineages.
Cellular and molecular heterogeneity could be dictated by transcription profiling, which is called the &#8216;single cell transcriptome&#8217; and emphasizes new approaches for quantifying gene expression levels8-10. For analysis of gene expression levels in individual cells, we developed a simple, but robust protocol of single cell quantitative RT-PCR. We confirmed the efficacy and feasibility of our protocol by comparing each half of single cell lysates as well as serially diluted total RNAs of hESCs, resulting in minimal technical variations and differences. Further, we used a genetic reporter line to isolate homogenous population of hESCs using gene targeting system. &#160;The donor vector for targeting OCT4 locus (OCT4-2A-EGFP-PGK-Puro construct) and a pair of TALEN plasmids were used11. The donor vector and a pair of TALEN plasmids were introduced into hESCs (H9, WA09) using our nucleofection and clonal selection protocol and maintenance of hESCs was performed based on our routine protocol12. We confirmed this genetic reporter line express EGFP for OCT4 expression in OCT4::EGFP hESCs.
Our result demonstrates that individual hESCs (sorted by OCT4::EGFP strongly positive cells) hold high levels of OCT4 expression, but different levels of NANOG expression. So, our single cell gene expression assay should be useful to study population heterogeneities of pluripotent stem cells.

<table border="0" cellpadding="0" cellspacing="0" width="807">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">96 wll PCR Plate</td>
			<td style="width:123px;">USA scientific</td>
			<td style="width:119px;">1402-8900</td>
			<td style="width:311px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:255px;">Ambion Cell Lysis Kit</td>
			<td style="width:123px;">Life Technologies</td>
			<td align="right" style="width:119px;">4458235</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">SMARTScribe Reverse Transcriptase</td>
			<td style="width:123px;">Clonetech</td>
			<td align="right" style="width:119px;">639536</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">ExoSAP-IT</td>
			<td style="width:123px;">USB</td>
			<td align="right" style="width:119px;">78200</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:255px;">Platinum Taq DNA polymerase High Fidelity</td>
			<td style="width:123px;">Invitrogen</td>
			<td align="right" style="width:119px;">11304</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">10mM dNTP Mix, PCR Grade</td>
			<td style="width:123px;">Invitrogen</td>
			<td align="right" style="width:119px;">18427</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">SYBR Universal 2X Master Mix</td>
			<td style="width:123px;">Kapa biosystem</td>
			<td style="width:119px;">KR0389</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Accutase</td>
			<td>Innovative Cell Tech</td>
			<td>S-1100-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">FACS buffer</td>
			<td style="width:123px;"></td>
			<td style="width:119px;"></td>
			<td>45 ml PBS, 5 ml a-MEM, 100 ul DNase, filter sterilized</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">35 &#956;m cell strainer cap tubes</td>
			<td style="width:123px;">BD Biosciences</td>
			<td align="right" style="width:119px;">352235</td>
			<td></td>
		</tr>
	</tbody>
</table>

profiling individual human embryonic stem cells by quantitative rt-pcr

Heterogeneity of stem cell population hampers detailed understanding of stem cell biology, such as their differentiation propensity toward different lineages. A single cell transcriptome assay can be a new approach for dissecting individual variation. We have developed the single cell qRT-PCR method, and confirmed that this method works well in several gene expression profiles. In single cell level, each human embryonic stem cell, sorted by OCT4::EGFP positive cells, has high expression in OCT4, but a different level of NANOG expression. Our single cell gene expression assay should be useful to interrogate population heterogeneities.

Efficient and robust single cell RNA amplification
To minimize the transcriptional variation among hESCs, we used OCT4::EGFP hESC clone for FACS purification. After sorting OCT4::EGFP positive cells into a 96-well plate, each cell is lysed in lysis buffer and converted poly(A)+ RNA to full length cDNA using SMA-T15 (GACATGTATCCGGATGTTTTTTTTTTTTTTTT) primer and anchoring with SMA-A (ACATGTATCCGGATGTGGG) by using SMART template switching technology. The excess oligonuc...

Watch this Scientific Journal Video about Profiling Individual Human Embryonic Stem Cells by Quantitative RT-PCR at JoVE.com

Profiling Individual Human Embryonic Stem Cells by Quantitative RT-PCR

Single cell gene expression assay is needed for understanding stem cell heterogeneities.

Heterogeneity of stem cell population hampers detailed understanding of stem cell biology, such as their differentiation propensity toward different ...

profiling-individual-human-embryonic-stem-cells-by-quantitative-rt-pcr

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11.4K Views.  Johns Hopkins University School of Medicine. Single cell gene expression assay is needed for understanding stem cell heterogeneities.

Video: Profiling Individual Human Embryonic Stem Cells by Quantitative RT-PCR

Propagation of Human Embryonic Stem (ES) Cells

Propagation of Human Embryonic Stem ES Cells

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 ...

Probing for Mitochondrial Complex Activity in Human Embryonic Stem Cells

Mitochondria are cytoplasmic organelles that have a primary role in cellular metabolism and homeostasis, regulation of the cell signaling network, and programmed cell death. Mitochondria produce ATP, regulate the cytoplasmic redox state and Ca2+ balance, catabolize fatty acids, synthesize heme, nucleotides, steroid hormones, amino acids, and help assemble iron-sulfur clusters in proteins. Mitochondria also have an essential role in heat production. Mutations of the mitochondrial genome cause several types of human disorder. The accumulation of mtDNA mutations correlates with aging and is suspected to have an important role in the development of cancer. Due to their vitally important role in all cell types, the function of mitochondria must also be critical for stem cells. Key advances have been made in our understanding of stem cell viability, proliferation, and differentiation capacity. But the functional activity of stem cells, in particular their energy status, was not yet been studied in detail. Almost nothing is known about the mitochondrial properties of human embryonic stem cells (hESCs) and their differentiated precursor progeny. One way to understand and evaluate the role of mitochondria in hESC function and developmental potential is to directly measure the activity of mitochondrial respiratory complexes. Here, we describe high resolution clear native gel electrophoresis and subsequent in gel activity visualization as a method for analyzing the five respiratory chain complexes of hESCs.

In this video, we will show you how the mitochondrial respiratory chain complexes of human embryonic stem cells can be analyzed using in gel activity assays.

Mitochondria are cytoplasmic organelles that have a primary role in cellular metabolism and homeostasis, regulation of the cell signaling network, and ...

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 Labeling of Human Embryonic Stem Cells for Magnetic Resonance Imaging

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of the predominant imaging modalities to assess the restoration of the injured myocardium. Furthermore, ex-vivo labeling agents, such as iron-oxide nanoparticles, have been employed to track and localize the transplanted stem cells. However, this method does not monitor a fundamental cellular biology property regarding the viability of transplanted cells. It has been known that manganese chloride (MnCl2) enters the cells via voltage-gated calcium (Ca2+) channels when the cells are biologically active, and accumulates intracellularly to generate T1 shortening effect. Therefore, we suggest that manganese-guided MRI can be useful to monitor cell viability after the transplantation of hESC into the myocardium.
In this video, we will show how to label hESC with MnCl2 and how those cells can be clearly seen by using MRI in vitro. At the same time, biological activity of Ca2+-channels will be modulated utilizing both Ca2+-channel agonist and antagonist to evaluate concomitant signal changes.

In this video, we are showing how to label human embryonic stem cells (hESC) with manganese chloride (MnCl2) which can enter cells via voltage-gated calcium channels when the cells are biologically active. Additionally, we show the use of MnCl2 as cellular MRI contrast agent to determine the in vitro viability of hESC.

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of ...

Culture and Maintenance of Human Embryonic Stem Cells  

Human embryonic stem (hES) cells must be monitored and cared for in order to maintain healthy, undifferentiated cultures. At minimum, the cultures must be  fed  every day by performing a complete medium change to replenish lost nutrients and to keep the cultures free of unwanted differentiation factors. Although a small amount of differentiation is normal and expected in stem cell cultures, the culture should be routinely cleaned up by manually removing, or "picking" differentiated areas. Identifying and removing excess differentiation from hES cell cultures are essential techniques in the maintenance of a healthy population of cells.

Culture and Maintenance of Human Embryonic Stem Cells

This protocol demonstrates how to maintain healthy, undifferentiated human embryonic stem (ES) cells.

Human embryonic stem (hES) cells must be monitored and cared for in order to maintain healthy, undifferentiated cultures. At minimum, the cultures must be ...

Chromosomal Spread Preparation of Human Embryonic Stem Cells for Karyotyping

Although human embryonic stem cells (hESC) have been shown to present a stable diploid karyotype 1, many studies have reported that depending on culture conditions they become prone to acquire chromosomal anomalies such as addition of whole or parts of chromosomes. Indeed, during long-term culture, karyotypic alterations are observed when enzymatic or chemical dissociation are used 2,3,4, while manual dissection of colonies for passaging retains a stable karyotype 5. Besides, changes in the environment such as the removal of feeder cells also seem to compromise the genetic integrity of hESC 3,6. Once chromosomal alterations could affect cellular physiology, the characterization of the genetic integrity of hESC in vitro is crucial considering hESC as an essential tool in embryogenesis studies and drug testing. Furthermore, for future therapeutic purposes chromosomal changes are a real concern as it is frequently associated to carcinogenesis.
Here we show a simple and useful method to obtain high quality chromosome spreads for subsequent analysis of chromosome set by G-banding, FISH, SKY or CGH techniques 7,8. We recommend checking the chromosomal status routinely with intervals of 5 passages in order to monitor the appearance of translocations and aneuploidies
Priscila Britto and Rafaela Sartore contributed equally to the paper.

Karyotyping is a simple and useful technique widely used for detecting genetic alterations. Here we describe a step by step protocol for chromosome spread preparation of human embryonic stem cells for monitoring the chromosomal status of these cells maintained in culture.

Although human embryonic stem cells (hESC) have been shown to present a stable diploid karyotype 1, many studies have reported that depending on culture ...

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 ...

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.

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 ...