We thank members of the Colas lab for helpful discussions and critical reviews of the manuscript. This study was supported by NIH/NIEHS R44ES023521-02 and CIRM DISC2-10110 grants to Dr. Colas.

1. Id1 Virus Preparation and Infection
<ol>
	<li>Generate Id1 overexpressing lentivirus by co-transfecting pCMVDR8.74, pMD2.G, and pCDH-EF1-Id1-PGK-PuroR (Addgene: plasmid #107735) into HEK293T cells. Collect viral particles, filtrate, purify from the supernatant, and store at -80 &#176;C as in Kitamura et al. (2003)19. Alternatively, produce Id1 lentivirus commercially by sending pCDH-EF1-Id1-PGK-PuroR to a lentivirus-producing vendor. 
	Caution: Please follow lentiviral safety re...

<ol>
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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=Human+embryonic-stem-cell-derived+cardiomyocytes+regenerate+non-human+primate+hearts.">Human embryonic-stem-cell-derived cardiomyocytes regenerate non-human primate hearts.</a> Nature. 510, 273-277 (2014).</li><li>Kodo, K., 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=iPSC-derived+cardiomyocytes+reveal+abnormal+TGF-beta+signalling+in+left+ventricular+non-compaction+cardiomyopathy.">iPSC-derived cardiomyocytes reveal abnormal TGF-beta signalling in left ventricular non-compaction cardiomyopathy.</a> Nature cell biology. 18, 1031-1042 (2016).</li><li>Kim, 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=Studying+arrhythmogenic+right+ventricular+dysplasia+with+patient-specific+iPSCs.">Studying arrhythmogenic right ventricular dysplasia with patient-specific iPSCs.</a> Nature. 494, 105-110 (2013).</li><li>Colas, A. 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A., 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=Cardiomyocytes+derived+from+human+embryonic+stem+cells+in+pro-survival+factors+enhance+function+of+infarcted+rat+hearts.">Cardiomyocytes derived from human embryonic stem cells in pro-survival factors enhance function of infarcted rat hearts.</a> Nature biotechnology. 25, 1015-1024 (2007).</li><li>Lian, X., 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=Robust+cardiomyocyte+differentiation+from+human+pluripotent+stem+cells+via+temporal+modulation+of+canonical+Wnt+signaling.">Robust cardiomyocyte differentiation from human pluripotent stem cells via temporal modulation of canonical Wnt signaling.</a> Proceedings of the National Academy of Sciences of the United States of America. 109, 1848-1857 (2012).</li><li>Willems, E., 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=Small+molecule-mediated+TGF-beta+type+II+receptor+degradation+promotes+cardiomyogenesis+in+embryonic+stem+cells.">Small molecule-mediated TGF-beta type II receptor degradation promotes cardiomyogenesis in embryonic stem cells.</a> Cell stem cell. 11, 242-252 (2012).</li><li>Yang, L., 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=Human+cardiovascular+progenitor+cells+develop+from+a+KDR++embryonic-stem-cell-derived+population.">Human cardiovascular progenitor cells develop from a KDR+ embryonic-stem-cell-derived population.</a> Nature. 453, 524-528 (2008).</li><li>Palpant, N. 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=Generating+high-purity+cardiac+and+endothelial+derivatives+from+patterned+mesoderm+using+human+pluripotent+stem+cells.">Generating high-purity cardiac and endothelial derivatives from patterned mesoderm using human pluripotent stem cells.</a> Nature protocols. 12, 15-31 (2017).</li><li>DeLaughter, D. M., 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=Single-cell+resolution+of+temporal+gene+expression+during+heart+development.">Single-cell resolution of temporal gene expression during heart development.</a> Developmental cell. 39, 480-490 (2016).</li><li>Liu, X., 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=The+complex+genetics+of+hypoplastic+left+heart+syndrome.">The complex genetics of hypoplastic left heart syndrome.</a> Nature genetics. 49, 1152-1159 (2017).</li><li>Corrado, D., Link, M. S., Calkins, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Arrhythmogenic+right+ventricular+cardiomyopathy.">Arrhythmogenic right ventricular cardiomyopathy.</a> New England journal of medicine. 376, 1489-1490 (2017).</li><li>Kitamura, 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=Retrovirus-mediated+gene+transfer+and+expression+cloning:+powerful+tools+in+functional+genomics.">Retrovirus-mediated gene transfer and expression cloning: powerful tools in functional genomics.</a> Experimental hematology. 31, 1007-1014 (2003).</li></ol>

The authors have nothing to disclose.

For successful differentiations, make sure to closely follow instructions listed above. In addition, here we highlight key parameters that strongly influence differentiation outcomes. Before starting a differentiation, the following three morphological parameters should be observed: a stem morphology of hPSCsId1, a high cellular compaction and a high confluence (&#62;90%) of the culture at day 0. In that regard, optimal differentiation conditions are best created by plating dissociated hPSCsId1 as s...

Large scale production of human pluripotent stem cells (hPSCs)-derived cardiac progenitors and cardiomyocytes is a pre-requisite for stem cell-based therapies1, disease modeling2,3 and the rapid characterization of novel pathways regulating cardiac differentiation4,5,6 and physiology7,8. Although a number of studies9,10,11,12,13,14,15 have previously described highly efficient cardiac differentiation protocols from hPSCs, none has addressed the heart field origin of resulting cardiomyocytes, in spite of the identification of significant molecular differences between left (first heart field) and right (second heart field) ventricular cardiomyocytes16 and the existence of heart field-specific congenital heart diseases; i.e., hypoplastic left heart syndrome17 or arrhythmogenic right ventricular dysplasia18. Thus, the generation of cardiac progenitors and cardiomyocytes of defined heart field origin from hPSCs is becoming a necessity in order to increase their relevance as therapeutic and disease modeling tools.
This protocol relies on the constitutive overexpression of Id1, a recently identified5 first heart field-specifying cue that in combination with Activin A, is both necessary and sufficient to initiate cardiogenesis in hPSCs. Notably, Cunningham et al. (2017)5 show that Id1-induced progenitors specifically express first heart field (HCN4, TBX5) but not second heart field markers (SIX2, ISL1) as they undergo cardiac differentiation. In addition, the authors also show that transgenic mouse embryos lacking the entire Id family of genes (Id1-4), develop without forming first heart field cardiac progenitors, while more medial and posterior cardiac progenitors (second heart field) can still form, thereby suggesting that Id proteins are essential to initiate first heart field cardiogenesis in vivo. Conveniently, Id1-induced progenitors can be cryopreserved and spontaneously differentiate into cardiomyocytes displaying ventricular-like characteristics, including ventricular-specific markers (IRX4, MYL2) expression and ventricular-like action potentials.
Here we describe a simple and scalable method to generate first heart field-like (FHF-L) cardiac progenitors and ventricular-like cardiomyocytes from Id1 overexpressing hPSCs. An important feature of this protocol is the possibility to uncouple cardiac progenitor generation from subsequent cardiomyocyte production using a convenient cryopreservation step. In summary, this protocol details the necessary steps to (1) generate Id1-overexpressing hPSCs, (2) generate FHF-L cardiac progenitors from hPSCs, (3) cryopreserve resulting progenitors, and (4) resume FHF-L cardiac progenitor differentiation and generate highly enriched (&#62;70&#8211;90%) beating ventricular-like cardiomyocytes.

<table border="0" cellpadding="0" cellspacing="0" style="width:911px;" width="910">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:204px;">ACTC1 antibody</td>
			<td style="width:144px;">Sigma</td>
			<td style="width:119px;">A7811</td>
			<td style="width:444px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Activin A</td>
			<td>Stem Cell Technologies</td>
			<td>Hu Recom Activin A</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Antibiotic Antimycotic (Anti-Anti)</td>
			<td>Thermo Fisher Scientific</td>
			<td>15240062</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">B27 supplement</td>
			<td>Thermo Fisher Scientific</td>
			<td>17504044</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">B27 supplement w/o - insulin</td>
			<td>Thermo Fisher Scientific</td>
			<td>A1895601</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">B27 supplement w/o - vitamin A</td>
			<td>Thermo Fisher Scientific</td>
			<td>12587001</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CDH5 antibody</td>
			<td style="width:144px;">R&#38;D Systems</td>
			<td>AF938</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CryoStor CS10</td>
			<td>Stem Cell Technologies</td>
			<td>7930</td>
			<td style="width:444px;">Cryopreservation reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DMEM high Glucose</td>
			<td>Mediatech</td>
			<td>10-013-CV&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DPBS w/ Ca &#38; Mg</td>
			<td>Corning</td>
			<td>21-030-CV</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">EDTA</td>
			<td>Thermo Fisher Scientific</td>
			<td>15575-038</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FBS</td>
			<td>VWR</td>
			<td>89510-186</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FluoVolt membrane potential kit&#160;&#160;</td>
			<td>Thermo Fisher Scientific</td>
			<td>F10488</td>
			<td>For optical action potential acquisition, please refer to McKeithan et al. 2017</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">KnockOut Serum Replacement</td>
			<td>Gibco</td>
			<td>10828010</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Matrigel, Growth Factor Reduced</td>
			<td>Corning</td>
			<td>356231</td>
			<td style="width:444px;">Coating reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">mTeSR1 media kit</td>
			<td>Stem Cell Technologies</td>
			<td>5850</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PBS w/o Ca &#38; Mg</td>
			<td>Corning</td>
			<td>21-040-CV</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Penicillin-Streptomycin</td>
			<td>Gibco</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Puromycin&#160;</td>
			<td>Acros</td>
			<td>227422500</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">ReLeSR</td>
			<td>Stem Cell Technologies</td>
			<td>5872</td>
			<td style="width:444px;">Enzyme-free dissociation reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">RPMI 1640</td>
			<td>Thermo Fisher Scientific</td>
			<td>11875-093</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TAGLN antibody</td>
			<td style="width:144px;">Abcam</td>
			<td>ab14106</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Thiazovivin</td>
			<td>Stem Cell Technologies</td>
			<td>72254</td>
			<td style="width:444px;">RHO/ROCK pathway inhibitor</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TrypLE Express</td>
			<td>Thermo Fisher Scientific</td>
			<td>12605 -010</td>
			<td style="width:444px;">1X enzyme-containing dissociation reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tyrodes solution mix packets&#160;&#160;</td>
			<td>Sigma</td>
			<td>T2145-10X1L</td>
			<td>(For optical action potential acquisition, please refer to McKeithan et al. 2017)</td>
		</tr>
	</tbody>
</table>

generation of first heart field-like cardiac progenitors and ventricular-like cardiomyocytes from human pluripotent stem cells

The generation of large amounts of functional human pluripotent stem cells-derived cardiac progenitors and cardiomyocytes of defined heart field origin is a pre-requisite for cell-based cardiac therapies and disease modeling. We have recently shown that Id genes are both necessary and sufficient to specify first heart field progenitors during vertebrate development. This differentiation protocol leverages these findings and uses Id1 overexpression in combination with Activin A as potent specifying cues to produce first heart field-like (FHF-L) progenitors. Importantly, resulting progenitors efficiently differentiate (~70&#8211;90%) into ventricular-like cardiomyocytes. Here we describe a detailed method to 1) generate Id1-overexpressing hPSCs and 2) differentiate scalable quantities of cryopreservable FHF-L progenitors and ventricular-like cardiomyocytes.

Generation of hPSCsId1lines 
hPSCs are infected with a lentivirus mediating Id1 overexpression (Figure 1A). Once hPSCId1 are generated, transgene expression is quantified by qRT-PCR (Figure 1B). Only hPSCId1 lines expressing Id1 mRNA at levels greater than 0.005 fold of that of GAPDH should ...

Watch this Scientific Journal Video about Generation of First Heart Field-like Cardiac Progenitors and Ventricular-like Cardiomyocytes from Human Pluripotent Stem Cells at JoVE.com

Generation of First Heart Field-like Cardiac Progenitors and Ventricular-like Cardiomyocytes from Human Pluripotent Stem Cells

Here we describe a scalable method, using a simple combination of Activin A and lentivirus-mediated Id1-overexpression, to generate first heart field-like cardiac progenitors and ventricular-like cardiomyocytes from human pluripotent stem cells.

The generation of large amounts of functional human pluripotent stem cells-derived cardiac progenitors and cardiomyocytes of defined heart field origin is ...

The main advantage of this simple technique is to generate cardiac progenitors and cardiomyocytes of defined heart field origin and subtypes. In turn, resulting cells can be used for a wide range of research application, including basic developmental biology, proof-of-concept cell-based therapy, and cardiac disease modeling studies. Demonstrating the procedure will be Sean Spiering and Michael Yu from my laboratory.To begin, coat enough wells of a 96-well plate with 50 microliters of coating reagent to accommodate subsequent cell seeding and viral infection steps, then add one milliliter of dissociation reagent to a well in the six-well plate to detach the pluripotent stem cells seeded. Then, use a sterile pipette to transfer the cell suspension in a 15-milliliter plastic centrifuge tube. In the tube, add five milliliters of PBS containing calcium and magnesium to neutralize the dissociation reagent.Then centrifuge the cells at 200 times g for three minutes. Post-centrifugation, discard the supernatant and then gently flick the tube for the pellet to be dislodged. Then dissolve the cell pellet in one milliliter of stem cell medium.Next, use an automated cell counter to count the number of cells. Once the counting is done, seed 20, 000 viable cells in each well of a 96-well plate containing 50 microliters of stem cell medium supplemented with two-micromolar RHO/ROCK pathway inhibitor. After 24 hours, monitor the cell attachment, then replace the medium with 100 microliters of stem cell medium one hour prior to the lentiviral infection.Next, thaw the Id1 lentivirus on ice, then add three microliters of purified lentivirus per well. After adding the lentivirus, transfer the plate back to cell culture incubator at 37 degrees Celsius with 5%carbon dioxide. 24 hours post-viral infection, add 100 microliters of fresh stem cell medium to the infected cells.After 48 hours, replace the virus-containing medium with 200 microliters of fresh stem cell medium supplemented with one microgram per milliliter of puromycin. Every day, keep changing the medium with fresh 200 microliters of stem cell medium supplemented with one microgram per milliliter of puromycin. Start the process of differentiation on Day 0 by replacing the stem cell medium with 1.5 milliliters of induction medium with Activin A in a 12-well plate.24 hours after differentiation has started, replace the medium with two milliliters of induction medium without Activin A.On the third day, replace with two milliliters of induction medium without Activin A.On the fifth day, aspirate the entire medium from the well containing the FHF-L CPs, then immediately add one milliliter of warm enzyme-containing dissociation reagent in the well, then incubate the culture plate at 37 degrees Celsius. After a minute, shake the plate inside the incubator and remove it from the incubator after two minutes, then add one milliliter of 10%fetal bovine serum-containing medium in the well. Detach the cells from the plate by gently pipetting the cells up and down.Next, transfer the cell suspension to a centrifuge tube and subject to centrifugation. After the centrifugation, dissolve the cell pellet in two milliliters of cryopreservation reagent, then count the cell number. Then transfer the cells in the cryopreservation vials and leave the vials in the cooling device.Then transfer the device at minus 80 degrees Celsius overnight. After 24 hours, transfer the vials in liquid nitrogen for long-term storage. Just before thawing the FHF-L CPs, coat the wells of the 12-well plate with two milliliters of coating reagent.Next transfer the five-days old FHF-L CPs from the liquid nitrogen in a dry ice container. From the dry ice, transfer the vial in a water bath at 37 degrees Celsius for two minutes to ensure complete thawing. After the cells are completely thawed, transfer the cells to a centrifuge tube, then pipette 10 drops of pre-warmed cardiogenic medium every 30 seconds to the cell solution.Keep adding the cardiogenic medium til the cryopreservation and cardiogenic medium ratio reaches one to three. Next subject the cells to centrifugation. Post-centrifugation remove the supernatant and carefully flick the tube, then dissolve the cell pellet in cardiogenic medium supplemented with two-micromolar RHO/ROCk pathway inhibitor.Further dilute the cell suspension with cardiogenic medium to achieve the desired cell concentration. Then seed the cells on the culture plate containing two milliliters of cardiogenic medium. Leave the plate in the tissue culture hood for 20 minutes before transferring to the incubator.Monitor the cell attachment on the sixth day of differentiation. On the seventh day, aspirate half of the cardiogenic medium and replace it with fresh medium. From here on out, replace 50%of the cardiogenic medium every other day, then, on the 15th day, quantify the cardiac differentiation.Here the expression level of Id1 mRNA is quantified in the hESC and hPSC cell lines. Only hPSC lines expressing Id1 mRNA at levels greater than 0.005-fold GAPDH are used for differentiation. Shown here are brightfield images post-differentiation of optimal, sub-confluent, and over-confluent hPSCs at Day 0.Upon further differentiation, the cell confluency reaches 75%after 24 hours. At Day 3, the differentiating cells form a cluster, and, by Day 5, the cells remain in tightly-connected clusters with homogenous morphology. At Day 6, the FHF-L CPs cover more than 90%of the surface area of the wells.In fact, by Day 12, the cardiomyocytes start to beat and display cardiac contractions. Further into the differentiation process, there are increased mRNA expression levels of MYL2 and IRX4 after Day 15. Both proteins represent ventricular-specific markers within the cardiomyocytes.Here the action potential trace represents the rapid upstroke and downstroke velocities as well as the ventricular plateau. These rates were characteristic of ventricular-like cardiomyocytes at Day 25 of differentiation. In summary, it takes about two weeks to generate Id1 over-expressing human pluripotent stem cells, then it takes about five days to generate first heart field-like progenitors and about 10 days to generate beating ventricular-like cardiomyocytes.

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6.9K visualizações.  Sanford Burnham Prebys Medical Discovery Institute. The main advantage of this simple technique is to generate cardiac progenitors and cardiomyocytes of defined heart field origin and subtypes. In turn, resulting cells can be used for a wide range of research application, including basic developmental biology, proof-of-concept cell-based therapy, and cardiac disease modeling studies. Demonstrating the procedure will be Sean Spiering and Michael Yu from my laboratory.To begin, coat enough wells of a 96-well plate with 50 microliters of c...