1. Recommendations Before Starting
<ol>
	<li>Do not use PSCs contaminated with mycoplasma because they will not differentiate properly into sinus node cells. Test for mycoplasma contamination before starting the protocol. Do this using a PCR kit for rapid, highly sensitive detection of mycoplasmas and follow the manufacturer`s protocol.</li>
	<li>For each Petri dish (step 2.3.4), coat one 10 cm2 cell culture dish with sterile 7 ml 0.1 % gelatin from cold water fish skin for 1 hr at 37 &#176;C. Remove the gel...

<ol>
	<li>Wobus, A. M., Wallukat, G., Hescheler, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pluripotent+mouse+embryonic+stem+cells+are+able+to+differentiate+into+cardiomyocytes+expressing+chronotropic+responses+to+adrenergic+and+cholinergic+agents+and+Ca2++channel+blockers.">Pluripotent mouse embryonic stem cells are able to differentiate into cardiomyocytes expressing chronotropic responses to adrenergic and cholinergic agents and Ca2+ channel blockers.</a> Differentiation. 48 (3), 173-182 (1991).</li><li>David, R., 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=MesP1+drives+vertebrate+cardiovascular+differentiation+through+Dkk-1-mediated+blockade+of+Wnt-signalling.">MesP1 drives vertebrate cardiovascular differentiation through Dkk-1-mediated blockade of Wnt-signalling.</a> Nat Cell Biol. 10, 338-345 (2008).</li><li>David, R., 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=Forward+programming+of+pluripotent+stem+cells+towards+distinct+cardiovascular+cell+types.">Forward programming of pluripotent stem cells towards distinct cardiovascular cell types.</a> Cardiovasc Res. 84 (2), 263-272 (2009).</li><li>Hoogaars, W. 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=Tbx3+controls+the+sinoatrial+node+gene+program+and+imposes+pacemaker+function+on+the+atria.">Tbx3 controls the sinoatrial node gene program and imposes pacemaker function on the atria.</a> Genes Dev. 21 (9), 1098-1112 (2007).</li><li>Klug, M. G., Soonpaa, M. H., Koh, G. Y., Field, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetically+selected+cardiomyocytes+from+differentiating+embronic+stem+cells+form+stable+intracardiac+grafts.">Genetically selected cardiomyocytes from differentiating embronic stem cells form stable intracardiac grafts.</a> J Clin Invest. 98 (1), 216-224 (1996).</li><li>Marger, 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=Pacemaker+activity+and+ionic+currents+in+mouse+atrioventricular+node+cells.">Pacemaker activity and ionic currents in mouse atrioventricular node cells.</a> Channels (Austin). 5 (3), 241-250 (2011).</li><li>Jung, J. 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=Programming+and+isolation+of+highly+pure+physiologically+and+pharmacologically+functional+sinus-nodal+bodies+from+pluripotent+stem+cells).">Programming and isolation of highly pure physiologically and pharmacologically functional sinus-nodal bodies from pluripotent stem cells).</a> Stem cell reports. 2 (5), 592-605 (2014).</li><li>Maltsev, V. A., Wobus, A. M., Rohwedel, J., Bader, M., Hescheler, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiomyocytes+differentiated+in+vitro+from+embryonic+stem+cells+developmentally+express+cardiac-specific+genes+and+ionic+currents.">Cardiomyocytes differentiated in vitro from embryonic stem cells developmentally express cardiac-specific genes and ionic currents.</a> Circulation research. 75 (2), 233-244 (1994).</li><li>He, J. Q., Ma, Y., Lee, Y., Thomson, J. A., Kamp, T. J. <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+cells+develop+into+multiple+types+of+cardiac+myocytes:+action+potential+characterization.">Human embryonic stem cells develop into multiple types of cardiac myocytes: action potential characterization.</a> Circ Res. 93 (1), 32-39 (2003).</li><li>Yanagi, 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=Hyperpolarization-activated+cyclic+nucleotide-gated+channels+and+T-type+calcium+channels+confer+automaticity+of+embryonic+stem+cell-derived+cardiomyocytes.">Hyperpolarization-activated cyclic nucleotide-gated channels and T-type calcium channels confer automaticity of embryonic stem cell-derived cardiomyocytes.</a> Stem cells. 25 (11), 2712-2719 (2007).</li><li>Barbuti, 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=Molecular+composition+and+functional+properties+of+f-channels+in+murine+embryonic+stem+cell-derived+pacemaker+cells.">Molecular composition and functional properties of f-channels in murine embryonic stem cell-derived pacemaker cells.</a> J Mol Cell Cardiol. 46 (3), 343-351 (2009).</li><li>Ma, 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+purity+human-induced+pluripotent+stem+cell-derived+cardiomyocytes:+electrophysiological+properties+of+action+potentials+and+ionic+currents.">High purity human-induced pluripotent stem cell-derived cardiomyocytes: electrophysiological properties of action potentials and ionic currents.</a> American journal of physiology. 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The authors have nothing to disclose.

The ability to produce stem cell derived cardiac pacemaker cells may allow reconstitution of the proper cardiac rhythm in the sense of &#8220;biological pacemakers&#8221;. Likewise, drug testing in vitro will benefit from their availability. PSCs can give rise to any cell type of the mammalian body including cardiomyocytes with pacemaker cell properties8,9,10,11,12,13. However, typically the cell populations within &#8220;Embryoid Bodies&#8221; are highly heterogeneous, which inevitably leads to the requiremen...

The term &#8220;sick sinus syndrome&#8221; summarizes multiple diseases leading to the deterioration of the cardiac pacemaker system. It comprises pathological, symptomatic sinus bradycardia, sinoatrial block, sinus arrest as well as the tachycardia-bradycardia syndrome. Thereby, a &#8220;sick sinus syndrome&#8221; is often accompanied by general cardiac diseases such as an ischemic heart disease, cardiomyopathies or myocarditis. At present, therapeutic approaches are based on the implantation of electrical pacemakers. However, this goes along with a number of risks such as infections and battery failure. Overall, the incidence of complications is still very high in patients having implanted an artificial pacemaker. Furthermore, as opposed to the endogenous pacemaker, these devices do not respond to hormone stimulation.
A future alternative may rely on the availability of &#8220;biological pacemakers&#8221; for which PSCs could serve as a suitable cellular source and which would also be highly valuable for in vitro drug testing. Yet, a major problem lies in the very rare appearance of sinus nodal cells within embryoid bodies (EBs) - this typically does not exceed ~0.5%1.
Previously, it was shown that &#8220;forward programming&#8221; towards specific cardiomyocyte subtypes is feasible via overexpression of distinct early cardiovascular transcription factors such as Mesoderm-specific-posterior 1 (MesP1) and NK2 transcription factor related, locus 5 (Nkx2.5)2,3. For normal size and function of the sinoatrial node (SAN), the T-box transcription factor Tbx3 is crucial, which has been shown to initiate the pacemaker gene program and to control differentiation of the SAN4. While this enhanced the appearance of functional pacemaker cells, the content still did not exceed ~40% within the entire cardiomyocytic cell population.
Therefore, an additional Myh6-promoter based antibiotic selection step5 was introduced by us. This ultimately leads to yet unobserved cardiomyocyte aggregates (&#8220;induced sino-atrial bodies; &#8220;iSABs&#8221;) which exhibit highly increased beating frequencies (&#62;400 bpm) in vitro, for the first time approximating those of a murine heart and comparable to in vitro cultivated sinus nodal cells isolated from a murine heart6. Under Isoprenaline administration even beating frequencies of 550 bpm are achieved. Notably, iSABs consist of over 80% functional nodal cells as evident from extensive physiological analyses7. Recently, several approaches to generate sinus nodal cells using direct reprogramming19, surface markers14 or pharmacological treatment with small molecules16,17 were described. Yet, none of these methods led to such a high purity of pacemaker cells and beating frequencies close to the murine heart as observed in iSABs.
Moreover, in an ex vivo model of cultivated adult mouse ventricular slices which have lost their spontaneous beating activity, the iSABs are capable of integrating into the slice tissue, thereby remaining spontaneously active and robustly pacing the heart slices to contractions7. A detailed protocol for the generation of these iSABs is described in this paper.

<table border="0" cellpadding="0" cellspacing="0" width="597">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:335px;">Name of the Material/Equipment</td>
			<td style="width:132px;">Company</td>
			<td style="width:131px;">Catalog Number</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Iscove&#39;s liquid medium with stable glutamine</td>
			<td>Biochrom AG</td>
			<td>FG 0465</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DMEM liquid medium without Na-pyruvate, with stable glutamine</td>
			<td>Biochrom AG</td>
			<td>FG 0435</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CLS type IV, CLS IV</td>
			<td>Biochrom AG</td>
			<td>C4-22</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Non-essential amino acids</td>
			<td>Biochrom AG</td>
			<td>K 0293</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FBS Superior</td>
			<td>Biochrom AG</td>
			<td>S 0615</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sodium pyruvate (100 mM)</td>
			<td>Biochrom AG</td>
			<td>L 0473</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">G 418-BC liquid (ready-to-use solution), sterile</td>
			<td>Biochrom AG</td>
			<td>A 2912</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Reagent reservoir PP f.multichannel pip. 60ml,sterile</td>
			<td>Brand</td>
			<td>703409</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Accutase</td>
			<td>eBioscience,Inc.</td>
			<td>00-4555-56</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Eppendorf Xplorer/Xplorer plus, electronic pipette</td>
			<td>Eppendorf</td>
			<td>4861000155</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Falcon Cell Strainer 40&#181;m</td>
			<td>Falcon</td>
			<td>352340</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Penicillin/Streptomycin&#160;</td>
			<td>GE Healthcare</td>
			<td>P11-010</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Petri Dishes</td>
			<td>Greiner BioOne</td>
			<td>663102</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DPBS without Ca and Mg</td>
			<td>PAN-Biotech</td>
			<td>P04-36500</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fetal bovine serum</td>
			<td>PAN-Biotech</td>
			<td>P30-3302</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Leukemia inhibitory factor</td>
			<td>Phoenix Europe GmbH</td>
			<td>LIF-250</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Quadratic petri dishes</td>
			<td>Roth</td>
			<td>PX67.1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Gelatin from cold water fish skin</td>
			<td>SigmaAldrich</td>
			<td>G7765</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2-Mercaptoethanol</td>
			<td>SigmaAldrich</td>
			<td>M3148&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1-Thioglycerol</td>
			<td>SigmaAldrich</td>
			<td>M6145</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tissue culture dishes</td>
			<td>TPP</td>
			<td>93100</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tissue culture flask</td>
			<td>TPP</td>
			<td>90076</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tissue culture test plates (24 well)</td>
			<td>TPP</td>
			<td>92424</td>
		</tr>
	</tbody>
</table>

generation of murine cardiac pacemaker cell aggregates based on es-cell-programming in combination with myh6-promoter-selection

Treatment of the &#8220;sick sinus syndrome&#8221; is based on artificial pacemakers. These bear hazards such as battery failure and infections. Moreover, they lack hormone responsiveness and the overall procedure is cost-intensive. &#8220;Biological pacemakers&#8221; generated from PSCs may become an alternative, yet the typical content of pacemaker cells in Embryoid Bodies (EBs) is extremely low. The described protocol combines &#8220;forward programming&#8221; of murine PSCs via the sinus node inducer TBX3 with Myh6-promoter based antibiotic selection. This yields cardiomyocyte aggregates consistent of &#62;80% physiologically functional pacemaker cells. These &#8220;induced-sinoatrial-bodies&#8221; (&#8220;iSABs&#8221;) are spontaneously contracting at yet unreached frequencies (400-500 bpm) corresponding to nodal cells isolated from mouse hearts and are able to pace murine myocardium ex vivo. Using the described protocol highly pure sinus nodal single cells can be generated which e.g. can be used for in vitro drug testing. Furthermore, the iSABs generated according to this protocol may become a crucial step towards heart tissue engineering.

The described protocol allows generation of iSABs with a beating frequency of around 450 bpm from PSCs (shown in the movie) which is near to the mouse heart beating frequency. After dissociation of iSABs (step 2.8.8) the observed single cells show the typical shape of cells of the sinus node (spindle and spider cells) as shown in Figure 1. These cells highly express proteins which are known to be essential for the function of the sinus node like hyperpolarization-activated cyclic nucleotide-gated cation ...

Watch this Scientific Journal Video about Generation of Murine Cardiac Pacemaker Cell Aggregates Based on ES-Cell-Programming in Combination with Myh6-Promoter-Selection at JoVE.com

Generation of Murine Cardiac Pacemaker Cell Aggregates Based on ES-Cell-Programming in Combination with Myh6-Promoter-Selection

This protocol describes how to produce functional sinus nodal tissue from murine pluripotent stem cells (PSC). T-Box3 (TBX3) overexpression plus cardiac Myosin-heavy-chain (Myh6) promoter antibiotic selection leads to highly pure pacemaker cell aggregates. These &#8220;Induced-sinoatrial-bodies&#8221; (&#8220;iSABs&#8221;) contain over 80% pacemaker cells, show highly increased beating rates and are able to pace myocardium ex vivo.

Treatment of the &#8220;sick sinus syndrome&#8221; is based on artificial pacemakers. These bear hazards such as battery failure and infections. Moreover, ...

generation-murine-cardiac-pacemaker-cell-aggregates-based-on-es-cell

Research

JoVE Journal

Developmental Biology

9.6K Görüntüleme.  University of Rostock.  Bu protokol, kemirgen pluripotent kök hücreler (PSC) fonksiyonel sinüs düğüm doku üretmek açıklamaktadır. T-Box3 (TBX3) ekspresyonu artı kalp Myosin ağır zincir (Myh6) promotör antibiyotik seçimi son derece saf kalp pili hücre agrega yol açar. Bu "İsteyerek-sinoatrial-organları" ("iSABs"), son derece dayak oranları arttı göstermek% 80'in üzerinde kalp pili hücreleri içeren ve miyokard ex vivo pace edebiliyoruz. 