Human embryonic stem cell studies in the Teitell lab are supported by a California Institute for Regenerative Medicine (CIRM) seed grant RS1-00313. We thank members of the Broad Center of Regenerative Medicine and Stem Cell Research at UCLA, especially Dr. Amander Clark, Dr. Jerome Zack, and members of the UCLA Broad Institute Stem Cell Core Facility for their support of our studies.

Splitting hESCs from Matrigel to Matrigel
Usually a confluent 6-well plate of hESCs on Matrigel can be split 1:3 to 1:5 to another Matrigel plate, with the wells becoming confluent again 4-5 days after splitting.
<ol>
<li>CM and Matrigel plates are prepared as described above before splitting. </li>
<li>On the day of splitting, wash each well for splitting with 1&times;PBS, pH7.4, add 1ml of 1mg/ml Dispase (dilute 5mg/ml stock solution with DMEM/F12 media) to each well, and incubate at 37&deg;C for 3 min. </li>
<li>Wash each well three times with 1&times;PBS, pH7.4, add 1ml of ES media without bFGF, use a cell scraper to scrape colonies off the bottom of the well, collect the suspended hESCs in a 50ml falcon tube, and pellet by centrifugation at 200g for 5 min at room temperature. </li>
<li>To re-plate the hESCs on Matrigel plates, first wash the Matrigel plates with DMEM/F12 and add 2.5ml of CM supplemented with 10ng/ml bFGF per well. Resuspend the hESC pellet in an appropriate volume of CM supplemented with 10ng/ml bFGF, pipette the cell suspension up and down three times. (NOTE: When hESCs for splitting come from Matrigel plates, the clumps are very easy to break; therefore three rounds of pipetting is enough and more pipetting may over-disrupt the colonies and make single cells.) Aliquot 0.5 ml of hESC clumps suspension per well of the 6-well Matrigel plate to achive 3ml per well as a final volume. Place the plate in a 37&deg;C incubator. </li>
</ol>
Detection of pluripotency markers by immunofluorescence microscopy
Immunofluorescence microscopy is used to examine the expression of hESC pluripotency markers Oct-4 and SSEA-4 during culturing.
<ol>
<li> Aspirate media from one well and wash with 1&times;PBS, pH 7.4. Add 2ml of 3.7% formaldehyde to the well to fix for 10 min. </li>
<li>Rinse with 1xPBS, pH 7.4, add 2ml methanol to the well and place at -20&deg;C for 2 min. </li>
<li>Rinse with 1xPBS, pH 7.4, and block with 1ml of 0.2% bovine serume albumin (BSA) for 5 min. </li>
<li>Add 1ml of Oct-4 or anti-h/mSSEA-4 antibody (1:200 dilution in 0.2% BSA), and incubate at room temperature for 1 hr or at 4&deg;C overnight. (NOTE: for SSEA-4 staining, go directly to step 6) </li>
<li>Rinse three times with 1xPBS, pH 7.4, add FITC-conjugated rabbit IgG (1:500 dilution in 0.2% BSA), and incubate at room temperature for 1 hr. </li>
<li>Rinse 3 times with 1xPBS, pH 7.4, and put a drop of mounting solution (can contain DAPI if nuclear visualization is desired) at the center of the well. Put coverslip on top of the cells, seal with nail polish, and evaluate by immunofluorescence microscopy.</li>
</ol>
Human embryonic stem cell receipts
ES media (Embryonic Stem cell media):
DMEM/F12 - 400ml Knockout Serum Replacer - 100ml Non-Essential Amino Acids - 5ml 200mM GlutaMax / BME Solution - 5ml Penicillin / Streptomycin - 5ml
Mix well and store final hESC Culture Media in 500ml bottles at 4&deg;C. Good for a maximum of two weeks.
MEF Culture Media:
DMEM - 1000ml FBS - 100ml Non-Essential Amino Acids - 10ml Glutamine - 10ml Penicllin / Streptomycin - 10ml
Mix well and store final MEF Culture Media at 4&deg;C.
200mM Glutamax / BME Solution:
Glutamax - 100ml &beta;-mercaptoethanol (Stock solution at 14.3M) - 140 &micro;1 Mix two solutions well and then aliquot 10ml portions. Keep aliquots at -20&deg;C. bFGF Solution (final concentration of stock: 10 micrograms/ml): bFGF (FGF2) - 50 &micro;g 0.1% BSA in 1xPBS, pH 7.4 - 5ml
Dissolve 50 micrograms bFGF in 5ml 0.1% BSA to make a 10 &micro;g/ml stock. Aliquot into 500 &micro;l portions. Store at -80&deg;C.
Collagenase IV Solution (1mg/ml):
Collagenase IV - 50mg DMEM/F12 Media - 50ml
Add the collagenase IV powder to a 50ml falcon tube. In the hood, mix in 50ml of sterile DMEM/F12 media. Vortex the solution for &lt; 1 min. to make sure the powder is dissolved. In the hood, pass through a 0.22 &micro;m filter into a new sterile 50ml falcon tube. This solution is good for a maximum of 2 weeks stored at 4&deg;C.
Dispase Solution (1mg/ml):
Dispase 5mg/ml - 2ml DMEM/F12 Media - 8ml Aliquot commercial 5mg/ml Dispase solution and store at -20&deg;C. Dilute dispase to 1mg/ml using DMEM/F12. This solution can be kept for 1 week at 4&deg;C.

<ol>
	<li>Thomson, J. a. m. e. s. A., Itskovitz-Eldor, J. o. s. e. p. h., Shapiro, S. a. n. d. e. r. S., Waknitz, M. i. c. h. e. l. l. e. A., Swiergiel, J. e. n. n. i. f. e. r. J., Marshall, V. i. v. i. e. n. n. e. S., Jones, J. e. f. f. r. e. y. M. <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>Xu, C. h. u. n. h. u. i., Inokuma, M. a. r. g. a. r. e. t. S., Denham, J. e. r. r. o. d., Golds, K. a. t. h. a. l. e. e. n., Kundu, P. r. a. t. i. m. a., Gold, J. o. s. e. p. h. D., Carpenter, M. e. l. i. s. s. a. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=+Feeder-free+growth+of+undifferentiated+human+embryonic+stem+cells+Nature+Biotechnology+19."> Feeder-free growth of undifferentiated human embryonic stem cells Nature Biotechnology 19.</a> Nature Biotechnology. 19, 971-974 (2001).</li></ol>

This series of 3 videos demonstrates how to grow human embryonic stem cells (hESCs) on mouse embryonic fibroblast (MEF) feeder cells (video 1), how to passage them to Matrigel feeder cell-free plates (video 2), and how to maintain hESCs by passaging in Matrigel feeder cell-free conditions (video 3). Numerous prior studies showed that maintenance of viable, undifferentiated hESCs requires culture on inactivated MEF feeder cells. However, for many experiments, a pure population of hESCs free of feeder cell contamination is...

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Knockout Serum Replacer (KSR)</td>
<td>Reagent</td>
<td>Gibco</td>
<td>10828-028</td>
<td>&nbsp;</td>
<tr>
<td>DMEM/F12</td>
<td>Reagent</td>
<td>Gibco</td>
<td>11330-057</td>
<td>&nbsp;</td>
<tr>
<td> Non-essential Amino Acids</td>
<td>Reagent</td>
<td>Gibco</td>
<td>11140-050</td>
<td>&nbsp;</td>
<tr>
<td>GlutaMax </td>
<td>Reagent</td>
<td>Gibco</td>
<td>35050-061</td>
<td>&nbsp;</td>
<tr>
<td>DMEM</td>
<td>Reagent</td>
<td>Gibco</td>
<td>11995-065</td>
<td>&nbsp;</td>
<tr>
<td>FBS</td>
<td>Reagent</td>
<td>Clontech</td>
<td>631107</td>
<td>&nbsp;</td>
<tr>
<td>L-glutamine</td>
<td>Reagent</td>
<td>Gibco</td>
<td>25030-081</td>
<td>&nbsp;</td>
<tr>
<td>BME</td>
<td>Reagent</td>
<td>Fisher</td>
<td>BP176-100</td>
<td>&nbsp;</td>
<tr>
<td>bFGF</td>
<td>Reagent</td>
<td>R&D Systems</td>
<td>233-FB-025</td>
<td>&nbsp;</td>
<tr>
<td>Collagenase IV</td>
<td>Reagent</td>
<td>Gibco</td>
<td>17104-019</td>
<td>&nbsp;</td>
<tr>
<td>Dispase</td>
<td>Reagent</td>
<td>Stem Cell Technologies</td>
<td>17105-041</td>
<td>&nbsp;</td>
<tr>
<td>Penicillin / Streptomycin </td>
<td>Reagent</td>
<td>Gibco</td>
<td>15140-122</td>
<td>&nbsp;</td>
<tr>
<td>Gelatin</td>
<td>Reagent</td>
<td>Chemicon</td>
<td>ES-006-B</td>
<td>&nbsp;</td>
<tr>
<td>Matrigel</td>
<td>Reagent</td>
<td>BD Biosciences</td>
<td>354277</td>
<td>&nbsp;</td>
<tr>
<td>Oct-4 antibody</td>
<td>Reagent</td>
<td>Santa Cruz Biotechnology</td>
<td>SC-9081</td>
<td>&nbsp;</td>
<tr>
<td>anti-h/mSSEA-4 Phycoerythrin Conjugated Mouse IgG3</td>
<td>Reagent</td>
<td>R&D Systems</td>
<td>FAB1435P</td>
<td>&nbsp;</td>
<tr>
<td>FITCI-conjugated antirabbit IgG</td>
<td>Reagent</td>
<td>Jackson ImmunoResearch Laboratories. Inc.</td>
<td>715-095-152</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>
			<div>
					</div>

from mefs to matrigel 3: passaging hescs from matrigel onto matrigel

This video demonstrates how to maintain the growth of human embryonic stem cells (hESCs) in feeder cell-free conditions and how to continuously passage hESCs in feeder cell-free conditions. Confirmation of hESC pluripotency grown in feeder cell-free conditions by immunofluorescence microscopy is also demonstrated.

Watch this Scientific Journal Video about From MEFs to Matrigel 3: Passaging hESCs from Matrigel onto Matrigel at JoVE.com

From MEFs to Matrigel 3: Passaging hESCs from Matrigel onto Matrigel

This video demonstrates how to maintain the growth of human embryonic stem cells (hESCs) in feeder cell-free conditions and how to continuously passage hESCs in feeder cell-free conditions. Confirmation of hESC pluripotency grown in feeder cell-free conditions by immunofluorescence microscopy is also demonstrated. Part 3 of 3.

This video demonstrates how to maintain the growth of human embryonic stem cells (hESCs) in feeder cell-free conditions and how to continuously passage ...

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13.7K Views.  University of California, Los Angeles. This video demonstrates how to maintain the growth of human embryonic stem cells (hESCs) in feeder cell-free conditions and how to continuously passage hESCs in feeder cell-free conditions. Confirmation of hESC pluripotency grown in feeder cell-free conditions by immunofluorescence microscopy is also demonstrated. Part 3 of 3.

Video: From MEFs to Matrigel 3: Passaging hESCs from Matrigel onto Matrigel

Passaging HuES Human Embryonic Stem Cell-lines with Trypsin.

In this video we demonstrate how our lab routinely passages HuES human embryonic stem cell lines with trypsin.  Human embryonic stem cells are artifacts of cell culture, and tend to acquire karyotypic abnormalities with high population doublings.  Proper passaging is essential for maintaining a healthy, undifferentiated, karyotypically normal HuES human embryonic stem cell culture.  First, an expanding culture is washed in PBS to remove residual media and cell debris, then cells are overlaid with a minimal volume of warm 0.05% Trypsin-EDTA.  Trypsin is left on the cells for up to five minutes, then cells are gently dislodged with a 2mL serological pipette.  The cell suspension is collected and mixed with a large volume of HuES media, then cells are collected by gentle centrifugation.  The inactivated trypsin media mixture is removed, and cells resuspended in pre-warmed HuES media.  An appropriate split ratio is calculated (generally 1:10 to 1:20), and cells re-plated onto a 1-2 day old plate containing a monolayer of irradiated mouse embryonic fibroblast feeder cells.  The newly seeded HuES culture plate is left undisturbed for 48 hrs, then media is changed every day thereafter.  It is important not to trpsinize down to a single cell suspension, as this increases the risk of introducing karyotypic abnormalities.

In this video we demonstrate how our lab routinely passages HuES human embryonic stem cell lines with trypsin. Brought to you by JoVE.

In this video we demonstrate how our lab routinely passages HuES human embryonic stem cell lines with trypsin.  Human embryonic stem cells are artifacts ...

Passaging Human Neural Stem Cells

The ability to manipulate human neural stem/precursor cells (hNSPCs) in vitro provides a means to investigate their utility as cell transplants for therapeutic purposes as well as to explore many fundamental processes of human neural development and pathology.  This protocol presents a simple method of culturing and passaging hNSPCs in hopes of standardizing this technique and increasing reproducibility of human stem cell research.  The hNSPCs we use were isolated from cadaveric postnatal brain cortices by the National Human Neural Stem Cell Resource and grown as adherent cultures on flasks coated with fibronectin (Palmer et al., 2001; Schwartz et al., 2003).  We culture our hNSPCs in a DMEM:F12 serum-free media supplemented with EGF, FGF, and PDGF and passage them 1:2 approximately every seven days.  Using these conditions, the majority of the cells in the culture maintain a bipolar morphology and express markers of undifferentiated neural stem cells (such as nestin and sox2).

The ability to manipulate human neural stem/precursor cells (hNSPCs) in vitro allows to investigate their utility as cell transplants for therapeutic purposes and to explore human neural development. This protocol presents a method of culturing and passaging hNSPCs in hopes of increasing reproducibility of human stem cell research.

The ability to manipulate human neural stem/precursor cells (hNSPCs) in vitro provides a means to investigate their utility as cell transplants for ...

From MEFs to Matrigel I: Passaging hESCs in the Presence of MEFs

This video demonstrates how to grow human embryonic stem cells (hESCs) on mouse embryonic fibroblast (MEF) feeder cells.


This video demonstrates how to grow human embryonic stem cells (hESCs) on mouse embryonic fibroblast (MEF) feeder cells. Part 1 of 3.

This video demonstrates how to grow human embryonic stem cells (hESCs) on mouse embryonic fibroblast (MEF) feeder cells.
...

Generating iPS Cells from MEFS through Forced Expression of Sox-2, Oct-4, c-Myc, and Klf4

Pluripotency can be induced in differentiated murine by viral transduction of Oct4, Sox2, Klf4, and c-Myc (Takahashi and Yamanaka, 2006; Wernig, et al., 2007; Okita, et al., 2007; Maherali, et al., 2007). We have devised a reprogramming strategy in which these four transcription factors are expressed from doxycycline (dox)-inducible lentiviral vectors (Brambrink et al., 2008). Using these inducible constructs, we can derive induced pluripotent stem (iPS) cells from mouse embryonic fibroblasts (MEFs). In this video, we demonstrate the procedure for the generation of inducible lentiviruses that express the four transcription factors and show how to infect MEFs with these viruses in order to produce iPS cells. By using inducible lentiviruses, the expression of the four factors in controlled by the addition of doxycyline to the culture medium. The advantage of this system over the traditional retroviral infection is the ability to turn the genes on and off so that the kinetics of reprogramming and gene expression requirements can be analyzed in detail.

This video shows the procedure for generating induced pluripotent stem cells using inducible lentivirus that express Oct4, Sox2, c-Myc and Klf4.

Pluripotency can be induced in differentiated murine by viral transduction of Oct4, Sox2, Klf4, and c-Myc (Takahashi and Yamanaka, 2006;  Wernig, et al., ...

From MEFs to Matrigel 2: Splitting hESCs from MEFs onto Matrigel

This video demonstrates how to grow human embryonic stem cells (hESCs) on mouse embryonic fibroblast (MEF) feeder cells, how to passage hESCs from MEF plates to feeder cell-free Matrigel plates.


This video demonstrates how to maintain the growth of human embryonic stem cells (hESCs) in feeder cell-free conditions and how to continuously passage hESCs in feeder cell-free conditions. Confirmation of hESC pluripotency grown in feeder cell-free conditions by immunofluorescence microscopy is also demonstrated. Part 2 of 3.

This video demonstrates how to grow human embryonic stem cells (hESCs) on mouse embryonic fibroblast (MEF) feeder cells, how to passage hESCs from MEF ...

Cargo Loading onto Kinesin Powered Molecular Shuttles

Cells have evolved sophisticated molecular machinery, such as kinesin motor proteins and microtubule filaments, to support active intracellular transport of cargo. While kinesins tail domain binds to a variety of cargoes, kinesins head domains utilize the chemical energy stored in ATP molecules to step along the microtubule lattice. The long, stiff microtubules serve as tracks for long-distance intracellular transport.
These motors and filaments can also be employed in microfabricated synthetic environments as components of molecular shuttles 1. In a frequently used design, kinesin motors are anchored to the track surface through their tails, and functionalized microtubules serve as cargo carrying elements, which are propelled by these motors. These shuttles can be loaded with cargo by utilizing the strong and selective binding between biotin and streptavidin. The key components (biotinylated tubulin, streptavidin, and biotinylated cargo) are commercially available.
Building on the classic inverted motility assay 2, the construction of molecular shuttles is detailed here. Kinesin motor proteins are adsorbed to a surface precoated with casein; microtubules are polymerized from biotinylated tubulin, adhered to the kinesin and subsequently coated with rhodamine-labeled streptavidin. The ATP concentration is maintained at subsaturating concentration to achieve a microtubule gliding velocity optimal for loading cargo 3. Finally, biotinylated fluorescein-labeled nanospheres are added as cargo. Nanospheres attach to microtubules as a result of collisions between gliding microtubules and nanospheres adhering to the surface.
The protocol can be readily modified to load a variety of cargoes such as biotinylated DNA4, quantum dots 5 or a wide variety of antigens via biotinylated antibodies 4-6.

Molecular shuttles consisting of functionalized microtubules gliding on surface-adhered kinesin motor proteins can serve as a nanoscale transport system. Here, the assembly of a typical shuttle system is described.

Cells have evolved sophisticated molecular machinery, such as kinesin motor proteins and microtubule filaments, to support active intracellular transport ...

An Introduction to Worm Lab: from Culturing Worms to Mutagenesis

This protocol describes procedures to maintain nematodes in the laboratory and how to mutagenize them using two alternative methods: ethyl methane sulfonate (EMS) and 4, 5', 8-trimethylpsoralen combined with ultraviolet light (TMP/UV). Nematodes are powerful biological systems for genetics studies because of their simple body plan and mating system, which is composed of self-fertilizing hermaphrodites and males that can generate hundreds of progeny per animal. Nematodes are maintained in agar plates containing a lawn of bacteria and can be easily transferred from one plate to another using a pick. EMS is an alkylating agent commonly used to induce point mutations and small deletions, while TMP/UV mainly induces deletions. Depending on the species of nematode being used, concentrations of EMS and TMP will have to be optimized. To isolate recessive mutations of the nematode Pristionchus pacificus, animals of the F2 generation were visually screened for phenotypes. To illustrate these methods, we mutagenized worms and looked for Uncoordinated (Unc), Dumpy (Dpy) and Transformer (Tra) mutants.

Screening for mutants with phenotypic defects is a straightforward method for identifying genes that function in a given biological process. In this article we describe how to culture free living worms (e.g., Pristionchus pacificus) in the laboratory and show two different mutagenesis methods, EMS and TMP/UV.

This protocol describes procedures to maintain nematodes in the laboratory and how to mutagenize them using two alternative methods: ethyl methane ...

A Matrigel-Based Tube Formation Assay to Assess the Vasculogenic Activity of Tumor Cells

Over the past several decades, a tube formation assay using growth factor-reduced Matrigel has been typically employed to demonstrate the angiogenic activity of vascular endothelial cells in vitro1-5. However, recently growing evidence has shown that this assay is not limited to test vascular behavior for endothelial cells. Instead, it also has been used to test the ability of a number of tumor cells to develop a vascular phenotype6-8. This capability was consistent with their vasculogenic behavior identified in xenotransplanted animals, a process known as vasculogenic mimicry (VM)9. There is a multitude of evidence demonstrating that tumor cell-mediated VM plays a vital role in the tumor development, independent of endothelial cell angiogenesis6, 10-13. For example, tumor cells were found to participate in the blood perfused, vascular channel formation in tissue samples from melanoma and glioblastoma patients8, 10, 11. Here, we described this tubular network assay as a useful tool in evaluation of vasculogenic activity of tumor cells. We found that some tumor cell lines such as melanoma B16F1 cells, glioblastoma U87 cells, and breast cancer MDA-MB-435 cells are able to form vascular tubules; but some do not such as colon cancer HCT116 cells. Furthermore, this vascular phenotype is dependent on cell numbers plated on the Matrigel. Therefore, this assay may serve as powerful utility to screen the vascular potential of a variety of cell types including vascular cells, tumor cells as well as other cells.

A tube formation assay is used to evaluate vascular activity of tumor cells.

Over the past several decades, a tube formation assay using growth factor-reduced Matrigel has been typically employed to demonstrate the angiogenic ...

Efficient Production and Purification of Recombinant Murine Kindlin-3 from Insect Cells for Biophysical Studies

Kindlins are essential coactivators, with talin, of the cell surface receptors&#160;integrins and also participate in integrin outside-in signalling, and the control of gene transcription in the cell nucleus. The kindlins are ~75 kDa multidomain proteins and bind to an NPxY motif and upstream T/S cluster of the integrin &#946;-subunit cytoplasmic tail. The hematopoietically-important kindlin isoform, kindlin-3, is critical for platelet aggregation during thrombus formation, leukocyte rolling in response to infection and inflammation and osteoclast podocyte formation in bone resorption. Kindlin-3&#39;s role in these processes has resulted in extensive cellular and physiological studies. However, there is a need for an efficient method of acquiring high quality milligram quantities of the protein for further studies. We have developed a protocol, here described, for the efficient expression and purification of recombinant murine kindlin-3 by use of a baculovirus-driven expression system in Sf9 cells yielding sufficient amounts of high purity full-length protein to allow its biophysical characterization. The same approach could be taken in the study of the other mammalian kindlin isoforms.

Kindlins are fundamental to cell adhesion through integrins but studies of them have been hampered by the difficulty encountered in expressing them recombinantly in bacterial hosts. We describe here methods for their efficient production in baculovirus-infected insect cells.

Kindlins are essential coactivators, with talin, of the cell surface receptors&#160;integrins and also participate in integrin outside-in signalling, and ...

Generation of Myospheres From hESCs by Epigenetic Reprogramming

Generation of a homogeneous and abundant population of skeletal muscle cells from human embryonic stem cells (hESCs) is a requirement for cell-based therapies and for a "disease in a dish" model of human neuromuscular diseases. Major hurdles, such as low abundance and heterogeneity of the population of interest, as well as a lack of protocols for the formation of three-dimensional contractile structures, have limited the applications of stem cells for neuromuscular disorders. We have designed a protocol that overcomes these limits by ectopic introduction of defined factors in hESCs - the muscle determination factor MyoD and SWI/SNF chromatin remodeling complex component BAF60C - that are able to reprogram hESCs into skeletal muscle cells. Here we describe the protocol established to generate hESC-derived myoblasts and promote their clustering into tridimensional miniaturized structures (myospheres) that functionally mimic miniaturized skeletal muscles7.

Here, we describe a protocol based on epigenetic reprogramming of human embryonic stem cells (hESCs) toward generating a homogeneous population of skeletal muscle progenitors that under permissive culture conditions form three-dimensional clusters of contractile myofibers (myospheres), which recapitulate biological features of human skeletal muscles.

Generation of a homogeneous and abundant population of skeletal muscle cells from human embryonic stem cells (hESCs) is a requirement for cell-based ...