We thank M. Kapitza, Margit Henry, Tamara Rotshteyn, Susan Rohani and Cornelia B&#246;ttinger for excellent technical support. This work was supported by grants from the German Research Foundation (RTG 1331) and the German Ministry for Research (BMBF).

<ol>
	<li>Liu, W. W., Deng, Y. G., Liu, Y., Gong, W. R., Deng, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stem+Cell+Models+for+Drug+Discovery+and+Toxicology+Studies.">Stem Cell Models for Drug Discovery and Toxicology Studies.</a> Journal of Biochemical and Molecular Toxicology. 27 (1), 17-27 (2013).</li><li>Zuba-Surma, E. K., Jozkowicz, A., Dulak, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stem+Cells+in+Pharmaceutical+Biotechnology.">Stem Cells in Pharmaceutical Biotechnology.</a> Current Pharmaceutical Biotechnology. 12 (11), 1760-1773 (2011).</li><li>Leist, M., Hartung, T., Nicotera, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+dawning+of+a+new+age+of+toxicology.">The dawning of a new age of toxicology.</a> ALTEX. 25 (2), 103-114 (2008).</li><li>Kuegler, P. B., 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=Markers+of+murine+embryonic+and+neural+stem+cells,+neurons+and+astrocytes:+reference+points+for+developmental+neurotoxicity+testing.">Markers of murine embryonic and neural stem cells, neurons and astrocytes: reference points for developmental neurotoxicity testing.</a> ALTEX. 27 (1), 17-42 (2010).</li><li>Yamada, 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=Human+oocytes+reprogram+adult+somatic+nuclei+of+a+type+1+diabetic+to+diploid+pluripotent+stem+cells.">Human oocytes reprogram adult somatic nuclei of a type 1 diabetic to diploid pluripotent stem cells.</a> Nature. , (2014).</li><li>Chambers, S. 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=Highly+efficient+neural+conversion+of+human+ES+and+iPS+cells+by+dual+inhibition+of+SMAD+signaling.">Highly efficient neural conversion of human ES and iPS cells by dual inhibition of SMAD signaling.</a> Nature Biotechnology. 27 (3), 275-280 (2009).</li><li>Takasato, 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=Directing+human+embryonic+stem+cell+differentiation+towards+a+renal+lineage+generates+a+self-organizing+kidney.">Directing human embryonic stem cell differentiation towards a renal lineage generates a self-organizing kidney.</a> Nature cell biology. 16 (1), 118-126 (2014).</li><li>Zimmer, B., 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=Evaluation+of+Developmental+Toxicants+and+Signaling+Pathways+in+a+Functional+Test+Based+on+the+Migration+of+Human+Neural+Crest+Cells.">Evaluation of Developmental Toxicants and Signaling Pathways in a Functional Test Based on the Migration of Human Neural Crest Cells.</a> Environmental Health Perspectives. 120 (8), 1116-1122 (2012).</li><li>Bosman, 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+and+Functional+Evidence+of+HCN4+and+Caveolin-3+Interaction+During+Cardiomyocyte+Differentiation+from+Human+Embryonic+Stem+Cells.">Molecular and Functional Evidence of HCN4 and Caveolin-3 Interaction During Cardiomyocyte Differentiation from Human Embryonic Stem Cells.</a> Stem Cells and Development. 22 (11), 1717-1727 (2013).</li><li>Sartiani, 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=Developmental+changes+in+cardiomyocytes+differentiated+from+human+embryonic+stem+cells:+A+molecular+and+electrophysiological+approach.">Developmental changes in cardiomyocytes differentiated from human embryonic stem cells: A molecular and electrophysiological approach.</a> Stem Cells. 25 (5), 1136-1144 (2007).</li><li>Xu, X. Q., 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=Chemically+defined+medium+supporting+cardiomyocyte+differentiation+of+human+embryonic+stem+cells.">Chemically defined medium supporting cardiomyocyte differentiation of human embryonic stem cells.</a> Differentiation. 76 (9), 958-970 (2008).</li><li>Pal, R., Mamidi, M. K., Das, A. K., Bhonde, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+analysis+of+cardiomyocyte+differentiation+from+human+embryonic+stem+cells+under+3-D+and+2-D+culture+conditions.">Comparative analysis of cardiomyocyte differentiation from human embryonic stem cells under 3-D and 2-D culture conditions.</a> Journal of Bioscience and Bioengineering. 115 (2), 200-206 (2013).</li><li>Subramanian, 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=Spheroid+Culture+for+Enhanced+Differentiation+of+Human+Embryonic+Stem+Cells+to+Hepatocyte-Like+Cells.">Spheroid Culture for Enhanced Differentiation of Human Embryonic Stem Cells to Hepatocyte-Like Cells.</a> Stem Cells and Development. 23 (2), 124-131 (2014).</li><li>Sivertsson, L., Synnergren, J., Jensen, J., Bjorquist, P., Ingelman-Sundberg, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hepatic+Differentiation+and+Maturation+of+Human+Embryonic+Stem+Cells+Cultured+in+a+Perfused+Three-Dimensional+Bioreactor.">Hepatic Differentiation and Maturation of Human Embryonic Stem Cells Cultured in a Perfused Three-Dimensional Bioreactor.</a> Stem Cells and Development. 22 (4), 581-594 (2013).</li><li>Jagtap, S., 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=Cytosine+arabinoside+induces+ectoderm+and+inhibits+mesoderm+expression+in+human+embryonic+stem+cells+during+multilineage+differentiation.">Cytosine arabinoside induces ectoderm and inhibits mesoderm expression in human embryonic stem cells during multilineage differentiation.</a> British Journal of Pharmacology. 162 (8), 1743-1756 (2011).</li><li>Krug, A. 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=Human+embryonic+stem+cell-derived+test+systems+for+developmental+neurotoxicity:+a+transcriptomics+approach.">Human embryonic stem cell-derived test systems for developmental neurotoxicity: a transcriptomics approach.</a> Archives of Toxicology. 87 (1), 123-143 (2013).</li><li>Leist, 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=Test+systems+of+developmental+toxicity:+state-of-the+art+and+future+perspectives.">Test systems of developmental toxicity: state-of-the art and future perspectives.</a> Archives of Toxicology. 87 (12), 2037-2042 (2013).</li><li>Itskovitz-Eldor, 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=Differentiation+of+human+embryonic+stem+cells+into+embryoid+bodies+compromising+the+three+embryonic+germ+layers.">Differentiation of human embryonic stem cells into embryoid bodies compromising the three embryonic germ layers.</a> Molecular medicine. 6 (2), 88-95 (2000).</li><li>Khoo, M. L. 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=Growth+and+differentiation+of+embryoid+bodies+derived+from+human+embryonic+stem+cells:+Effect+of+glucose+and+basic+fibroblast+growth+factor.">Growth and differentiation of embryoid bodies derived from human embryonic stem cells: Effect of glucose and basic fibroblast growth factor.</a> Biology of Reproduction. 73 (6), 1147-1156 (2005).</li><li>Son, M. Y., Kim, H. J., Kim, M. J., Cho, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical+Passaging+of+Embryoid+Bodies+Generated+from+Human+Pluripotent+Stem+Cells.">Physical Passaging of Embryoid Bodies Generated from Human Pluripotent Stem Cells.</a> Plos One. 6 (5), (2011).</li><li>Winkler, J., Sotiriadou, I., Chen, S., Hescheler, J., Sachinidis, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+potential+of+embryonic+stem+cells+combined+with+-omics+technologies+as+model+systems+for+toxicology.">The potential of embryonic stem cells combined with -omics technologies as model systems for toxicology.</a> Current medicinal chemistry. 16 (36), 4814-4827 (2009).</li><li>Gunaseeli, I., Doss, M. X., Antzelevitch, C., Hescheler, J., Sachinidis, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induced+pluripotent+stem+cells+as+a+model+for+accelerated+patient-+and+disease-specific+drug+discovery.">Induced pluripotent stem cells as a model for accelerated patient- and disease-specific drug discovery.</a> Current medicinal chemistry. 17 (8), 759-766 (2010).</li><li>Miller, M. T., Stromland, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Teratogen+update:+Thalidomide:+A+review,+with+a+focus+on+ocular+findings+and+new+potential+uses.">Teratogen update: Thalidomide: A review, with a focus on ocular findings and new potential uses.</a> Teratology. 60 (5), 306-321 (1999).</li><li>Newman, C. G. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Teratogen+Update+-+Clinical+Aspects+of+Thalidomide+Embryopathy+-+A+Continuing+Preoccupation.">Teratogen Update - Clinical Aspects of Thalidomide Embryopathy - A Continuing Preoccupation.</a> Teratology. 32 (1), 133-144 (1985).</li><li>Stern, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+assessment+of+the+teratogenic+potential+of+drugs+in+humans.">In vivo assessment of the teratogenic potential of drugs in humans.</a> Obstetrics and gynecology. 58 (5 Suppl), 3S-8S (1981).</li><li>Lynch, H. T., Reich, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diethylstilbestrol,+Genetics,+Teratogenesis,+and+Tumor+Spectrum+in+Humans.">Diethylstilbestrol, Genetics, Teratogenesis, and Tumor Spectrum in Humans.</a> Medical Hypotheses. 16 (3), 315-332 (1985).</li><li>Satoh, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+teratology+of+mercury+and+its+compounds.">Behavioral teratology of mercury and its compounds.</a> Tohoku Journal of Experimental Medicine. 201 (1), 1-9 (2003).</li><li>Meganathan, 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=Identification+of+Thalidomide-Specific+Transcriptomics+and+Proteomics+Signatures+during+Differentiation+of+Human+Embryonic+Stem+Cells.">Identification of Thalidomide-Specific Transcriptomics and Proteomics Signatures during Differentiation of Human Embryonic Stem Cells.</a> Plos One. 7 (8), (2012).</li><li>Balmer, N. V., 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=Epigenetic+changes+and+disturbed+neural+development+in+a+human+embryonic+stem+cell-based+model+relating+to+the+fetal+valproate+syndrome.">Epigenetic changes and disturbed neural development in a human embryonic stem cell-based model relating to the fetal valproate syndrome.</a> Human Molecular Genetics. 21 (18), 4104-4114 (2012).</li><li>Smirnova, L., Hogberg, H. T., Leist, M., Hartung, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developmental+neurotoxicity+-+Challenges+in+the+21st+Century+and+In+Vitro+Opportunities.">Developmental neurotoxicity - Challenges in the 21st Century and In Vitro Opportunities.</a> ALTEX. 31 (2), 129-156 (2014).</li><li>Leist, M., Efremova, L., Karreman, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Food+for+thought+...+considerations+and+guidelines+for+basic+test+method+descriptions+in+toxicology.">Food for thought ... considerations and guidelines for basic test method descriptions in toxicology.</a> ALTEX. 27 (4), 309-317 (2010).</li><li>Zimmer, B., 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=Coordinated+waves+of+gene+expression+during+neuronal+differentiation+of+embryonic+stem+cells+as+basis+for+novel+approaches+to+developmental+neurotoxicity+testing.">Coordinated waves of gene expression during neuronal differentiation of embryonic stem cells as basis for novel approaches to developmental neurotoxicity testing.</a> Cell Death and Differentiation. 18 (3), 383-395 (2011).</li><li>Kraljevic, S., Stambrook, P. J., Pavelic, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accelerating+drug+discovery.">Accelerating drug discovery.</a> EMBO Reports. 5 (9), 837-842 (2004).</li></ol>

The authors have nothing to disclose.

传统方法毒理试验涉及广泛的动物研究中从而使测试昂贵和费时。此外，由于种间差异的临床前动物安全性研究并不总是有效的预测与人类有关的潜在药物毒性作用。虽然非人类灵长类动物是最可预测的，还是强烈的伦理和socioeconomical需求正在迅速被现代社会提高发展中国家在体外试验敏感和强大 有关人类的安全系统。 人类胚胎干细胞的独特能力分化成所有的?...

人类胚胎干细胞（hESC细胞）的分化成各种细胞的能力打开了体外毒性试验1中 ，疾病建模和再生医学2的新时代。干细胞被赋予的能力，自我复制，以保持其多能状态，并分化成特定细胞3,4。的人类胚胎干细胞的特性（容量来区分所有主要的细胞类型），也发现在其它人多能干细胞，如人类诱导多能干细胞（hiPSC）或通过核移植5产生的细胞。例如，许多不同的hESC细胞系已分化为神经元6，肾细胞7，神经嵴细胞8，心肌9-12，或肝细胞样细胞13,14。此外，人类胚胎干细胞可自发地分化成胚状体（EB）19,20所有三种胚层15-18的细胞。 Ë阿尔利胚胎发育是通过与已捕获在mRNA水平通过使用微阵列技术15转录的不同胚层的多种基因的差异表达调控。这些努力使建立基于人类胚胎干细胞/ hiPSC和转录组分析（综述见21,22）器官特异性毒性模型。这些车型有优势的传统使用实验动物的毒理学研究，如使用实验动物并不总是预测人类安全的临床前研究。在患者中遇到的药物诱导的毒性往往与人类和实验动物之间是不同的代谢或信号传导过程。的物种差异防止了可靠的早期检测发育毒性在人类，例如药物如沙利度胺23,24和己烯雌酚25,26从市场上撤回由于致畸。塔利domide并没有表现出在大鼠或小鼠任何发育毒性。环境化学品如甲基汞27导致相对于神经系统中的各种物种产前发育毒性，但人的表现已经很难在动物模型。为了解决种属特异性问题的问题，科学家们根据不同的项目工作的基础上的干细胞一样重新保护，ESNATS，侦探等所从事的不同型号的发展胚胎毒性，神经毒性，心脏毒性，肝毒性和肾毒性涉嫌使用对人体有毒物质影响人类。根据欧洲联盟项目的胚胎干细胞为基础的新型替代测试策略（ESNATS）“五个测试系统已经建立。一个测试系统的所谓UKK（UniversitätsķlinikumķOLN）测试系统部分捕捉人类早期胚胎发育。在这个System人类胚胎H9细胞分化中15和胚层特定的签名已被抓获转录使用Affymetrix芯片平台简介三个胚层（外胚层，内胚层和中胚层）。像沙利度胺28，丙戊酸，甲基汞16,17，或阿糖胞苷15各个发育毒物在该系统已经过测试，并且具体毒物基因签名已被获得。在第二测试系统，即所谓的UKN1（U。高校ķonsta N个Z的）测试系统1中，H9细胞分化到神经外胚层祖细胞（NEP）6天。这是通过高表达的神经基因标记如PAX6和OTX2证实。在分化6天，NEP细胞已经暴露于发育神经毒物如丙戊酸钠，甲基汞。毒物特异性解除管制的转录概况已obtai通过使用Affymetrix芯片平台定义16,29以及。 对于21 世纪的毒理学的新远景设想，测试系统不仅产生的表型的描述，如组织病理学体内 ，或转录变化在长期毒物孵化结束。它，而表明试验提供机械信息3，而该信息可以被映射到所谓的不利后果的途径（AOP），提供了一个科学原理为危险影响30。为了提供这种信息，应用的测试系统必须高度控制质量31，作为例如通过稳健标准操作程序记载。此外，依赖于时间的变化需要被映射为高的分辨率。这就要求测试系统同步变化32。这里所描述的UKN1和UKK测试系统进行了优化这些需求。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>DMEM/F-12</td>
			<td>Life Technologies</td>
			<td>11320082</td>
			<td>Dulbecco&#39;s Modified Eagle Medium:Nutrient Mixture F-12</td>
		</tr>
		<tr>
			<td>KOSR</td>
			<td>Life Technologies</td>
			<td>10828028</td>
			<td>Knockout Serum Replacement</td>
		</tr>
		<tr>
			<td>GlutaMAX</td>
			<td>Life Technologies</td>
			<td>35050061</td>
			<td>GlutaMAX supplement</td>
		</tr>
		<tr>
			<td>NEAA</td>
			<td>Life Technologies</td>
			<td>11140050</td>
			<td>MEM Nonessential Amino Acids Solution</td>
		</tr>
		<tr>
			<td>DPBS</td>
			<td>Life Technologies</td>
			<td>14190-0144</td>
			<td>Dulbecco&#39;s Phosphate-Buffered Saline, without calcium, without magnesium</td>
		</tr>
		<tr>
			<td>mTeSR medium</td>
			<td>Stemcell Technologies</td>
			<td>5850</td>
			<td></td>
		</tr>
		<tr>
			<td>Pluronic F-127</td>
			<td>Sigma</td>
			<td>P2443-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>V bottom plate</td>
			<td>VWR</td>
			<td>734-0483</td>
			<td>Plate,Microwell,V BTTM,96 Well,Sterile 1 * 50 ST</td>
		</tr>
		<tr>
			<td>Vbottom plate lid</td>
			<td>VWR</td>
			<td>634-0011</td>
			<td>Lid, Microtitre plates, Cond. Ring 1 * 50 ST</td>
		</tr>
		<tr>
			<td>Pen/Strep</td>
			<td>Life Technologies</td>
			<td>15140-122</td>
			<td>Penicillin- Streptomycin, Liquid</td>
		</tr>
		<tr>
			<td>Distilled Water</td>
			<td>Life Technologies</td>
			<td>15230-089.</td>
			<td>Sterile Distilled Water</td>
		</tr>
		<tr>
			<td>Human FGF-2 (bFGF)</td>
			<td>Millipore</td>
			<td>GF003AF-100UG</td>
			<td>Fibroblast Growth Factor basic, human recombinant, animal-free</td>
		</tr>
		<tr>
			<td>Filter 0.22 &#956;m</td>
			<td>Millipore</td>
			<td>SCGPU02RE</td>
			<td>Stericup-GP, 0.22 &#956;m, polyethersulfone, 250 ml, radio- sterilized</td>
		</tr>
		<tr>
			<td>StemPro EZPassageTM Disposablte</td>
			<td>Invitrogen</td>
			<td>23181010</td>
			<td></td>
		</tr>
		<tr>
			<td>BD MatrigelTM, hESC qualified Matrix</td>
			<td>Stemcell Technologies</td>
			<td>354277</td>
			<td>5 ml vial</td>
		</tr>
		<tr>
			<td>DMSO</td>
			<td>Sigma</td>
			<td>D-2650</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAlater Stabilization Solution</td>
			<td>Life Technologies</td>
			<td>AM7020</td>
			<td>It stabilizes and protect the RNA integrity in unfrozen samples.</td>
		</tr>
		<tr>
			<td>70 &#956;m Cell Strainer</td>
			<td>Becton Dickinson</td>
			<td>352350</td>
			<td>Cell strainer with 70 &#956;m Nylon mesh</td>
		</tr>
		<tr>
			<td>35 &#956;m Lid cell strainer, 5 ml tube</td>
			<td>Becton Dickinson</td>
			<td>352235</td>
			<td>5 ml polystyrene round bottom test tube, with a cell strainer cap (35 &#956;m)</td>
		</tr>
		<tr>
			<td>50 ml sterile Polypropylene tube</td>
			<td>Greiner Bio-One</td>
			<td>227261</td>
			<td>50 ml Polypropylene tube with conical bottom, Sterile</td>
		</tr>
		<tr>
			<td>T75 flask</td>
			<td>Greiner Bio-One</td>
			<td>658175</td>
			<td>CELLSTAR Filter Cap Cell Culture 75 cm2 Flasks</td>
		</tr>
		<tr>
			<td>TRIzol</td>
			<td>Life Technologies</td>
			<td>10296010</td>
			<td></td>
		</tr>
		<tr>
			<td>96 well optical bottom plates</td>
			<td>Thermo Scientific</td>
			<td>165305</td>
			<td></td>
		</tr>
		<tr>
			<td>CellTiter-Blue</td>
			<td>Promega</td>
			<td>G8081</td>
			<td></td>
		</tr>
		<tr>
			<td>Accutase</td>
			<td>PAA</td>
			<td>L11-007</td>
			<td></td>
		</tr>
		<tr>
			<td>Apotransferin</td>
			<td>Sigma-Aldrich</td>
			<td>T-2036</td>
			<td></td>
		</tr>
		<tr>
			<td>Dispase</td>
			<td>Worthington Biochemicals</td>
			<td>LS002104</td>
			<td></td>
		</tr>
		<tr>
			<td>Dorsomorphin</td>
			<td>Tocris Bioscience</td>
			<td>3093</td>
			<td></td>
		</tr>
		<tr>
			<td>EDTA</td>
			<td>Roth</td>
			<td>8043.2</td>
			<td></td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>PAA</td>
			<td>A15-101</td>
			<td></td>
		</tr>
		<tr>
			<td>FGF-2</td>
			<td>R&#38;D Systems</td>
			<td>233-FB</td>
			<td></td>
		</tr>
		<tr>
			<td>Gelatine</td>
			<td>Sigma-Aldrich</td>
			<td>G1890-100G</td>
			<td></td>
		</tr>
		<tr>
			<td>Glucose</td>
			<td>Sigma-Aldrich</td>
			<td>G7021-100G</td>
			<td></td>
		</tr>
		<tr>
			<td>GlutaMAX</td>
			<td>Gibco Invitrogen</td>
			<td>35050-038</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Gibco Invitrogen</td>
			<td>15630-056</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulin</td>
			<td>Sigma-Aldrich</td>
			<td>I-6634</td>
			<td></td>
		</tr>
		<tr>
			<td>Knockout DMEM</td>
			<td>Gibco Invitrogen</td>
			<td>10829-018</td>
			<td></td>
		</tr>
		<tr>
			<td>Matrigel</td>
			<td>BD Biosciences</td>
			<td>354234</td>
			<td></td>
		</tr>
		<tr>
			<td>Noggin</td>
			<td>R&#38;D Systems</td>
			<td>719-NG</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Biochrom AG</td>
			<td>L1825</td>
			<td></td>
		</tr>
		<tr>
			<td>Progesteron</td>
			<td>Sigma-Aldrich</td>
			<td>P7556</td>
			<td></td>
		</tr>
		<tr>
			<td>Putrescine</td>
			<td>Sigma-Aldrich</td>
			<td>P-5780</td>
			<td></td>
		</tr>
		<tr>
			<td>ROCK inhibitor Y-27632</td>
			<td>Tocris Biosciences</td>
			<td>1254</td>
			<td></td>
		</tr>
		<tr>
			<td>SB431542</td>
			<td>Tocris Biosciences</td>
			<td>1614</td>
			<td></td>
		</tr>
		<tr>
			<td>SDS</td>
			<td>Bio-Rad</td>
			<td>161-0416</td>
			<td></td>
		</tr>
		<tr>
			<td>Selenium</td>
			<td>Sigma-Aldrich</td>
			<td>S-5261</td>
			<td></td>
		</tr>
		<tr>
			<td>&#946;-Mercaptoethanol</td>
			<td>Gibco Invitrogen</td>
			<td>31350-010</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>List of Kits</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>RNeasy Mini Kit (250)</td>
			<td>QIAGEN</td>
			<td>74106</td>
			<td></td>
		</tr>
		<tr>
			<td>GeneChip Hybridization, Wash, and Stain Kit</td>
			<td>Affymetrix</td>
			<td>900721, 22, 23</td>
			<td>This kit provides all reagents required for hybridization wash and staining of microarrays.</td>
		</tr>
		<tr>
			<td>Rnase-Free DNase Set</td>
			<td>QIAGEN</td>
			<td>79254</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td colspan="4">List of equipment.</td>
		</tr>
		<tr>
			<td>Inverted microscope</td>
			<td>Olympus</td>
			<td></td>
			<td>IX71</td>
		</tr>
		<tr>
			<td>Genechip Hybridisation Oven - 645</td>
			<td>Affymetrix</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Genechip Fluidics Station-450</td>
			<td>Affymetrix</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Affymetrix Gene-Chip Scanner-3000-7 G</td>
			<td>Affymetrix</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Spectramax M5</td>
			<td>Molecular Devices</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>List of softwares</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Prism 4</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Affymetrix GCOS</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Partek Genomic Suite 6.25</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Online tools for Functional annotation 
			DAVID 
			Onto-tools Intelligent Systems and Bioinformatics Laboratory</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

human pluripotent stem cell based developmental toxicity assays for chemical safety screening and systems biology data generation

高效的协议来区分人多能干细胞，以组合各种组织与组学技术开辟了新的视野为潜在药物的体外毒性测试。为了提供这种试验坚实的科学基础，这将是非常重要的获得发展的时间进程和底层的监管机制，系统生物学方法的定量信息。两个实验都因此被调整为在这里这些要求。在UKK测试系统中，人胚胎干细胞（hESC细胞）（或其它多能细胞）都留给自发分化为胚状体14天，以允许产生所有三个胚层的细胞。该系统概括的人类早期胚胎发育的关键步骤，并且它可以预测人特异性早期胚胎毒性/致畸性，如果细胞分化过程中暴露于化学品。所述UKN1测试系统是基于人类胚胎干细胞分化为一个populat神经外胚层祖离子（NEP）细胞6天。该系统概括早期神经发育，并预测早期发育神经毒性和化学品引发的表观遗传变化。两个系统，在与转录微阵列研究结合，适合于识别的毒性的生物标志物。此外，它们也可以组合使用以产生用于系统生物学分析的输入数据。这些测试系统具有比传统的毒理学研究需要大量的动物的优点。该测试系统可能有助于减少药物开发和化学安全性评价的费用。他们的组合揭示尤其是对可能影响具体化合物的神​​经发育光。

在UKK测试系统甲基汞暴露与H9的EB进行的细胞毒性测定，得到的IC 10值（10％减少活力的）甲基汞的细胞毒性（ 图1）。我们还进行了微阵列基础（Affymetrix公司的平台）的生物标志物研究。的H9的EB已暴露于甲基汞（0.25和1μM）14天。在第14天，将样品已收集使用Trizol和分离RNA。使用人类基因组U133加2.0阵列芯片进行转录谱。的数据进行了分析以将Partek基因组套?...

Watch this Scientific Journal Video about Human Pluripotent Stem Cell Based Developmental Toxicity Assays for Chemical Safety Screening and Systems Biology Data Generation at JoVE.com

Human Pluripotent Stem Cell Based Developmental Toxicity Assays for Chemical Safety Screening and Systems Biology Data Generation

该协议描述了基于人胚胎干细胞和转录研究2 在体外发育毒性试验系统（UKK和UKN1）。测试系统预测人类发育毒性危险，并可能有助于减少动物研究中，成本和所需的化学安全测试的时间。

基于发育毒性测定化学品安全筛选和系统生物学数据生成人类多能干细胞

Efficient protocols to differentiate human pluripotent stem cells to various tissues in combination with -omics technologies opened up new horizons for in ...

human-pluripotent-stem-cell-based-developmental-toxicity-assays-for

Research

JoVE Journal

Developmental Biology

12.4K 次观看.  University of Cologne. 该协议描述了基于人胚胎干细胞和转录研究2 在体外发育毒性试验系统（UKK和UKN1）。测试系统预测人类发育毒性危险，并可能有助于减少动物研究中，成本和所需的化学安全测试的时间。 

视频: Human Pluripotent Stem Cell Based Developmental Toxicity Assays for Chemical Safety Screening and Systems Biology Data Generation

Generation of Genetically Modified Organotypic Skin Cultures Using Devitalized Human Dermis

Organotypic cultures allow the reconstitution of a 3D environment critical for cell-cell contact and cell-matrix interactions which mimics the function and physiology of their in vivo tissue counterparts. This is exemplified by organotypic skin cultures which faithfully recapitulates the epidermal differentiation and stratification program. Primary human epidermal keratinocytes are genetically manipulable through retroviruses where genes can be easily overexpressed or knocked down. These genetically modified keratinocytes can then be used to regenerate human epidermis in organotypic skin cultures providing a powerful model to study genetic pathways impacting epidermal growth, differentiation, and disease progression. The protocols presented here describe methods to prepare devitalized human dermis as well as to genetically manipulate primary human keratinocytes in order to generate organotypic skin cultures. Regenerated human skin can be used in downstream applications such as gene expression profiling, immunostaining, and chromatin immunoprecipitations followed by high throughput sequencing. Thus, generation of these genetically modified organotypic skin cultures will allow the determination of genes that are critical for maintaining skin homeostasis.

The goal of this paper is to provide a comprehensive and detailed protocol on how to generate genetically modified human organotypic skin from epidermal keratinocytes and devitalized human dermis.

转基因器官皮肤培养使用灭活人真皮代

Organotypic cultures allow the reconstitution of a 3D environment critical for cell-cell contact and cell-matrix interactions which mimics the function ...

科研

发育生物学

Culturing Human Pluripotent and Neural Stem Cells in an Enclosed Cell Culture System for Basic and Preclinical Research

This paper describes how to use a custom manufactured, commercially available enclosed cell culture system for basic and preclinical research. Biosafety cabinets (BSCs) and incubators have long been the standard for culturing and expanding cell lines for basic and preclinical research. However, as the focus of many stem cell laboratories shifts from basic research to clinical translation, additional requirements are needed of the cell culturing system. All processes must be well documented and have exceptional requirements for sterility and reproducibility. In traditional incubators, gas concentrations and temperatures widely fluctuate anytime the cells are removed for feeding, passaging, or other manipulations. Such interruptions contribute to an environment that is not the standard for cGMP and GLP guidelines. These interruptions must be minimized especially when cells are utilized for therapeutic purposes. The motivation to move from the standard BSC and incubator system to a closed system is that such interruptions can be made negligible. Closed systems provide a work space to feed and manipulate cell cultures and maintain them in a controlled environment where temperature and gas concentrations are consistent. This way, pluripotent and multipotent stem cells can be maintained at optimum health from the moment of their derivation all the way to their eventual use in therapy.

Here is a protocol to grow pluripotent stem cells (PSC) and neural stem cells (NSC) in an enclosed cell culture system that permits maximum sterility and reproducibility, replacing the traditional biosafety cabinet and incubator. This equipment meets clinical good manufacturing practice (cGMP) and clinical good lab practice (cGLP) guidelines.

培养人多能性和神经干细胞的基本和临床前研究一个封闭的细胞培养系统

This paper describes how to use a custom manufactured, commercially available enclosed cell culture system for basic and preclinical research. Biosafety ...

Feeder-free Derivation of Melanocytes from Human Pluripotent Stem Cells

Human pluripotent stem cells (hPSCs) represent a platform to study human development in vitro under both normal and disease conditions. Researchers can direct the differentiation of hPSCs into the cell type of interest by manipulating the culture conditions to recapitulate signals seen during development. One such cell type is the melanocyte, a pigment-producing cell of neural crest (NC) origin responsible for protecting the skin against UV irradiation. This protocol presents an extension of a currently available in vitro Neural Crest differentiation protocol from hPSCs to further differentiate NC into fully pigmented melanocytes. Melanocyte precursors can be enriched from the Neural Crest protocol via a timed exposure to activators of WNT, BMP, and EDN3 signaling under dual-SMAD-inhibition conditions. The resultant melanocyte precursors are then purified and matured into fully pigmented melanocytes by culture in a selective medium. The resultant melanocytes are fully pigmented and stain appropriately for proteins characteristic of mature melanocytes.

This work describes an in vitro differentiation protocol to produce pigmented, mature melanocytes from human pluripotent stem cells via a neural crest and melanoblast intermediate stage using a feeder-free, 25 day protocol.

从人多能干细胞的黑素细胞的无饲养推导

Human pluripotent stem cells (hPSCs) represent a platform to study human development in vitro under both normal and disease conditions. Researchers can ...

Large-Scale Production of Cardiomyocytes from Human Pluripotent Stem Cells Using a Highly Reproducible Small Molecule-Based Differentiation Protocol

Maximizing the benefit of human pluripotent stem cells (hPSCs) for research, disease modeling, pharmaceutical and clinical applications requires robust methods for the large-scale production of functional cell types, including cardiomyocytes. Here we demonstrate that the temporal manipulation of WNT, TGF-&#946;, and SHH signaling pathways leads to highly efficient cardiomyocyte differentiation of single-cell passaged hPSC lines in both static suspension and stirred suspension bioreactor systems. Employing this strategy resulted in ~ 100% beating spheroids, consistently containing &#62; 80% cardiac troponin T-positive cells after 15 days of culture, validated in multiple hPSC lines. We also report on a variation of this protocol for use with cell lines not currently adapted to single-cell passaging, the success of which has been verified in 42 hPSC lines. Cardiomyocytes generated using these protocols express lineage-specific markers and show expected electrophysiological functionalities. Our protocol presents a simple, efficient and robust platform for the large-scale production of human cardiomyocytes.

Here, we present a robust, fast and scalable cardiomyocyte differentiation protocol for human pluripotent stem cells (hPSCs). Cardiomyocytes derived using this large-scale method can provide sufficient cell numbers for their effective use in human cardiovascular disease modeling, high-throughput drug screening, and potentially clinical applications.

从人多能干细胞使用高度可重复的小分子为基础的分化协议心肌细胞规模化生产

Maximizing the benefit of human pluripotent stem cells (hPSCs) for research, disease modeling, pharmaceutical and clinical applications requires robust ...

Generation of Integration-free Induced Pluripotent Stem Cells from Human Peripheral Blood Mononuclear Cells Using Episomal Vectors

Induced Pluripotent Stem Cells (iPSCs) hold great promise for disease modeling and regenerative therapies. We previously reported the use of Episomal Vectors (EV) to generate integration-free iPSCs from peripheral blood mononuclear cells (PB MNCs). The episomal vectors used are DNA plasmids incorporated with oriP and EBNA1 elements from the Epstein-Barr (EB) virus, which&#160;allow for replication and long-term retainment of plasmids in mammalian cells, respectively. With further optimization, thousands of iPSC colonies can be obtained from 1 mL of peripheral blood. Two critical factors for achieving high reprogramming efficiencies&#160;are: 1) the use of a 2A &#34;self-cleavage&#34; peptide to link OCT4 and SOX2, thus achieving equimolar expression of the two factors; 2) the use of two vectors to express MYC and KLF4 individually. Here we describe a step-by-step protocol for generating integration-free iPSCs from adult peripheral blood samples. The generated iPSCs are integration-free as residual episomal plasmids are undetectable after five passages. Although the reprogramming efficiency is comparable to that of Sendai Virus (SV) vectors, EV plasmids are considerably more economical than the commercially available SV vectors. This affordable EV reprogramming system holds potential for clinical applications in regenerative medicine and provides an approach for the direct reprogramming of PB MNCs to integration-free mesenchymal stem cells, neural stem cells, etc.

This protocol describes a detailed method for efficient generation of integration-free iPSCs from human adult peripheral blood cells. With the use of four oriP/EBNA-based episomal vectors to express the reprogramming factors, KLF4, MYC, BCL-XL, or OCT4 and SOX2, thousands of iPSC colonies can be obtained from 1 mL of peripheral blood.

从人体外周血单个核细胞融合，无诱导多能干细胞的生成方法游离型载体

Induced Pluripotent Stem Cells (iPSCs) hold great promise for disease modeling and regenerative therapies. We previously reported the use of Episomal ...

Defined and Scalable Generation of Hepatocyte-like Cells from Human Pluripotent Stem Cells

Human pluripotent stem cells (hPSCs) possess great value for biomedical research. hPSCs can be scaled and differentiated to all cell types found in the human body. The differentiation of hPSCs to human hepatocyte-like cells (HLCs) has been extensively studied, and efficient differentiation protocols have been established. The combination of extracellular matrix and biological stimuli, including growth factors, cytokines, and small molecules, have made it possible to generate HLCs that resemble primary human hepatocytes. However, the majority of procedures still employ undefined components, giving rise to batch-to-batch variation. This serves as a significant barrier to the application of the technology. To tackle this issue, we developed a defined system for hepatocyte differentiation using human recombinant laminins as extracellular matrices in combination with a serum-free differentiation process. Highly efficient hepatocyte specification was achieved, with demonstrated improvements in both HLC function and phenotype. Importantly, this system is easy to scale up using research and GMP-grade hPSC lines&#160;promising advances in cell-based modelling and therapies.

The method presented here describes a scalable and good manufacturing practice (GMP)-ready differentiation system to generate human hepatocyte-like cells from pluripotent stem cells. It serves as a cost-effective and standardized system to generate human hepatocyte-like cells for basic and applied human liver research.

界定和由人多能干细胞的肝细胞样细胞的可扩展代

Human pluripotent stem cells (hPSCs) possess great value for biomedical research. hPSCs can be scaled and differentiated to all cell types found in the ...

Rapid, Directed Differentiation of Retinal Pigment Epithelial Cells from Human Embryonic or Induced Pluripotent Stem Cells

We describe a robust method to direct the differentiation of pluripotent stem cells into retinal pigment epithelial cells (RPE). The purpose of providing a detailed and thorough protocol is to clearly demonstrate each step and to make this readily available to researchers in the field. This protocol results in a homogenous layer of RPE with minimal or no manual dissection needed. The method presented here has been shown to be effective for induced pluripotent stem cells (iPSC) and human embryonic stem cells. Additionally, we describe methods for cryopreservation of intermediate cell banks that allow long-term storage. RPE generated using this protocol might be useful for iPSC disease-in-a-dish modeling or clinical application.

This protocol describes how to produce retinal pigment epithelial cells (RPE) from pluripotent stem cells. The method uses a combination of growth factors and small molecules to direct the differentiation of stem cells into immature RPE in fourteen days and mature, functional RPE after three months.

人胚胎或诱导多能干细胞对视网膜色素上皮细胞的快速定向分化

We describe a robust method to direct the differentiation of pluripotent stem cells into retinal pigment epithelial cells (RPE). The purpose of providing ...

Chemical Reversion of Conventional Human Pluripotent Stem Cells to a Na&#239;ve-like State with Improved Multilineage Differentiation Potency

Na&#239;ve human pluripotent stem cells (N-hPSC) with improved functionality may have a wide impact in regenerative medicine. The goal of this protocol is to efficiently revert lineage-primed, conventional human pluripotent stem cells (hPSC) maintained on either feeder-free or feeder-dependent conditions to a na&#239;ve-like pluripotency with improved functionality. This chemical na&#239;ve reversion method employs the classical leukemia inhibitory factor (LIF), GSK3&#946;, and MEK/ERK inhibition cocktail (LIF-2i), supplemented with only a tankyrase inhibitor XAV939 (LIF-3i). LIF-3i reverts conventional hPSC to a stable pluripotent state adopting biochemical, transcriptional, and epigenetic features of the human pre-implantation epiblast. This LIF-3i method requires minimal cell culture manipulation and is highly reproducible in a broad repertoire of human embryonic stem cell (hESC) and transgene-free human induced pluripotent stem cell (hiPSC) lines. The LIF-3i method does not require a re-priming step prior to the differentiation; N-hPSC can be differentiated directly with extremely high efficiencies and maintain karyotypic and epigenomic stabilities (including at imprinted loci). To increase the universality of the method, conventional hPSC are first cultured in the LIF-3i cocktail supplemented with two additional small molecules that potentiate protein kinase A (forskolin) and sonic hedgehog (sHH) (purmorphamine) signaling (LIF-5i). This brief LIF-5i adaptation step significantly enhances the initial clonal expansion of conventional hPSC and permits them to be subsequently na&#239;ve-reverted with LIF-3i alone in bulk quantities, thus obviating the need for picking/subcloning rare N-hPSC colonies later. LIF-5i-stabilized hPSCs are subsequently maintained in LIF-3i alone without the need of anti-apoptotic molecules. Most importantly, LIF-3i reversion markedly improves the functional pluripotency of a broad repertoire of conventional hPSC by decreasing their lineage-primed gene expression and erasing the interline variability of directed differentiation commonly observed amongst independent hPSC lines. Representative characterizations of LIF-3i-reverted N-hPSC are provided, and experimental strategies for functional comparisons of isogenic hPSC in lineage-primed vs. na&#239;ve-like states are outlined.

Chemical Reversion of Conventional Human Pluripotent Stem Cells to a Na&amp;#239;ve-like State with Improved Multilineage Differentiation Potency

We present a protocol for efficient, bulk, and rapid chemical reversion of conventional lineage-primed human pluripotent stem cells (hPSC) into an epigenomically-stable na&#239;ve preimplantation epiblast-like pluripotent state. This method results in decreased lineage-primed gene expression and marked improvement in directed multilineage differentiation across a broad repertoire of conventional hPSC lines.

改良多向分化效力的常规人多能干细胞的化学逆转与幼稚样态

Na&#239;ve human pluripotent stem cells (N-hPSC) with improved functionality may have a wide impact in regenerative medicine. The goal of this protocol is ...

RNA-based Reprogramming of Human Primary Fibroblasts into Induced Pluripotent Stem Cells

Induced pluripotent stem cells (iPSCs) have proven to be a valuable tool to study human development and disease. Further advancing iPSCs as a regenerative therapeutic requires a safe, robust, and expedient reprogramming protocol. Here, we present a clinically relevant, step-by-step protocol for the extremely high-efficiency reprogramming of human dermal fibroblasts into iPSCs using a non-integrating approach. The core of the protocol consists of expressing pluripotency factors (SOX2, KLF4, cMYC, LIN28A, NANOG, OCT4-MyoD fusion) from in vitro transcribed messenger RNAs synthesized with modified nucleotides (modified mRNAs). The reprogramming modified mRNAs are transfected into primary fibroblasts every 48 h together with mature embryonic stem cell-specific microRNA-367/302 mimics for two weeks. The resulting iPSC colonies can then be isolated and directly expanded in feeder-free conditions. To maximize efficiency and consistency of our reprogramming protocol across fibroblast samples, we have optimized various parameters including the RNA transfection regimen, timing of transfections, culture conditions, and seeding densities. Importantly, our method generates high-quality iPSCs from most fibroblast sources, including difficult-to-reprogram diseased, aged, and/or senescent samples.

Here we describe a clinically relevant, high-efficiency, feeder-free method to reprogram human primary fibroblasts into induced pluripotent stem cells using modified mRNAs encoding reprogramming factors and mature microRNA-367/302 mimics. Also included are methods to assess reprogramming efficiency, expand clonal iPSC colonies, and confirm expression of the pluripotency marker TRA-1-60.

基于 rna 的人原代成纤维细胞重组成诱导多能干细胞

Induced pluripotent stem cells (iPSCs) have proven to be a valuable tool to study human development and disease. Further advancing iPSCs as a regenerative ...

Efficient Differentiation of Human Pluripotent Stem Cells into Liver Cells

The liver detoxifies harmful substances, secretes vital proteins, and executes key metabolic activities, thus sustaining life. Consequently, liver failure&#8212;which can be caused by chronic alcohol intake, hepatitis, acute poisoning, or other insults&#8212;is a severe condition that can culminate in bleeding, jaundice, coma, and eventually death. However, approaches to treat liver failure, as well as studies of liver function and disease, have been stymied in part by the lack of a plentiful supply of human liver cells. To this end, this protocol details the efficient differentiation of human pluripotent stem cells (hPSCs) into hepatocyte-like cells, guided by a developmental roadmap that describes how liver fate is specified across six consecutive differentiation steps. By manipulating developmental signaling pathways to promote liver differentiation and to explicitly suppress the formation of unwanted cell fates, this method efficiently generates populations of human liver bud progenitors and hepatocyte-like cells by days 6 and 18 of PSC differentiation, respectively. This is achieved through the temporally-precise control of developmental signaling pathways, exerted by small molecules and growth factors in a serum-free culture medium. Differentiation in this system occurs in monolayers and yields hepatocyte-like cells that express characteristic hepatocyte enzymes and have the ability to engraft a mouse model of chronic liver failure. The ability to efficiently generate large numbers of human liver cells in vitro has ramifications for treatment of liver failure, for drug screening, and for mechanistic studies of liver disease.

This protocol details a monolayer, serum-free method to efficiently generate hepatocyte-like cells from human pluripotent stem cells (hPSCs) in 18 days. This entails six steps as hPSCs sequentially differentiate into intermediate cell-types such as the primitive streak, definitive endoderm, posterior foregut and liver bud progenitors before forming hepatocyte-like cells.