Name: using human induced pluripotent stem cell-derived hepatocyte-like cells for drug discovery
Uploaded: 2018-05-19T12:30:00
Description: Watch this Scientific Journal Video about Using Human Induced Pluripotent Stem Cell-derived Hepatocyte-like Cells for Drug Discovery at JoVE.com

This work was supported by the National Institutes of Health (DK55743, DK087377, DK102716 and HG006398 to S.A.D). We would like to thank Dr. Behshad Pournasr, Dr. James Heslop and Ran Jing for their contributions.

1. Culture of Human Induced Pluripotent Stem Cells
<ol>
	<li>Coating recombinant Human E-Cadherin Fc Fusion Protein (E-cad-Fc) or other matrices suitable for hPSC culture6
	<ol>
		<li>Dilute E-cad-Fc to 15 &#956;g/mL with Dulbecco&#39;s Phosphate-Buffered Saline containing calcium and magnesium (DPBS (+)).</li>
		<li>Coat 100-mm suspension tissue culture dishes with 5 mL of diluted E-cad-Fc and incubate at 37 &#730;C for at least 1 h. Remove substrate and replace with 5 mL of me...

<ol>
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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=A+Drug+Screen+using+Human+iPSC-Derived+Hepatocyte-like+Cells+Reveals+Cardiac+Glycosides+as+a+Potential+Treatment+for+Hypercholesterolemia.">A Drug Screen using Human iPSC-Derived Hepatocyte-like Cells Reveals Cardiac Glycosides as a Potential Treatment for Hypercholesterolemia.</a> Cell Stem Cell. 20 (4), 478-489 (2017).</li><li>Nagaoka, 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=E-cadherin-coated+plates+maintain+pluripotent+ES+cells+without+colony+formation.">E-cadherin-coated plates maintain pluripotent ES cells without colony formation.</a> PLoS One. 1, e15 (2006).</li><li>Ludwig, T. 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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=Modeling+inherited+metabolic+disorders+of+the+liver+using+human+induced+pluripotent+stem+cells.">Modeling inherited metabolic disorders of the liver using human induced pluripotent stem cells.</a> J Clin Invest. 120 (9), 3127-3136 (2010).</li><li>Lu, W. Y., 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=Hepatic+progenitor+cells+of+biliary+origin+with+liver+repopulation+capacity.">Hepatic progenitor cells of biliary origin with liver repopulation capacity.</a> Nat Cell Biol. 17 (8), 971-983 (2015).</li><li>Ogawa, 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=Directed+differentiation+of+cholangiocytes+from+human+pluripotent+stem+cells.">Directed differentiation of cholangiocytes from human pluripotent stem cells.</a> Nat Biotechnol. 33 (8), 853-861 (2015).</li><li>Sampaziotis, F., 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=Cholangiocytes+derived+from+human+induced+pluripotent+stem+cells+for+disease+modeling+and+drug+validation.">Cholangiocytes derived from human induced pluripotent stem cells for disease modeling and drug validation.</a> Nat Biotechnol. 33 (8), 845-852 (2015).</li><li>Mallanna, S. 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A. <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+hepatocytes+from+pluripotent+stem+cells.">Differentiation of hepatocytes from pluripotent stem cells.</a> Curr Protoc Stem Cell Biol. 26 (Unit 1G 4), (2013).</li><li>Song, Z., 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=Efficient+generation+of+hepatocyte-like+cells+from+human+induced+pluripotent+stem+cells.">Efficient generation of hepatocyte-like cells from human induced pluripotent stem cells.</a> Cell Res. 19 (11), 1233-1242 (2009).</li><li>Cai, 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=Directed+differentiation+of+human+embryonic+stem+cells+into+functional+hepatic+cells.">Directed differentiation of human embryonic stem cells into functional hepatic cells.</a> Hepatology. 45 (5), 1229-1239 (2007).</li><li>Si-Tayeb, 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=Highly+efficient+generation+of+human+hepatocyte-like+cells+from+induced+pluripotent+stem+cells.">Highly efficient generation of human hepatocyte-like cells from induced pluripotent stem cells.</a> Hepatology. 51 (1), 297-305 (2010).</li><li>Pashos, E. 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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=Efficient+drug+screening+and+gene+correction+for+treating+liver+disease+using+patient-specific+stem+cells.">Efficient drug screening and gene correction for treating liver disease using patient-specific stem cells.</a> Hepatology. 57 (6), 2458-2468 (2013).</li><li>Tafaleng, E. N., 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=Induced+pluripotent+stem+cells+model+personalized+variations+in+liver+disease+resulting+from+alpha1-antitrypsin+deficiency.">Induced pluripotent stem cells model personalized variations in liver disease resulting from alpha1-antitrypsin deficiency.</a> Hepatology. 62 (1), 147-157 (2015).</li><li>Jing, R., Duncan, C. B., Duncan, S. 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Target based drug discovery, where small molecules are identified that influence the activity of a specific protein, has been the focus of many existing screening efforts. Although this approach has provided numerous pharmaceuticals, screens based on reversing a phenotype, classical pharmacology, have been more successful in identifying first-in-class compounds that have been clinically efficacious1. A disadvantage to phenotypic drug discovery is that it relies on the availability of appropriate d...

Success in identifying drugs that can be used to target a rare disease relies on the development of assays that can be used for screening. Hypothesis or target-based screens (reverse pharmacology) are useful, but require a detailed understanding of the molecular basis of the disease. Phenotypic screens (classical pharmacology) avoid the need for a detailed understanding of biochemical pathways, but instead rely on the development of models that accurately mirror the pathophysiology of the disease. Despite enthusiasm for target-based approaches, analyses of FDA approved first-in-class drugs reveal that phenotypic screens have been far more successful1. The overall goal of this method is to establish a platform for high throughput screening that can be used to identify small molecules for the treatment of metabolic liver disease. Several in vitro models have been described including primary hepatocytes, hepatoma cells, and liver progenitor cells2. However, most of these models have limitations, and there is a need for new models that can accurately recapitulate the pathophysiology of metabolic liver deficiencies in culture. Recently, human pluripotent stem cells combined with gene editing have offered an opportunity to model even the rarest of rare diseases in culture without the need to access patients directly3. While the use of patient-specific iPSCs as a tool to discover small molecules for the treatment of rare liver diseases is conceptually reasonable, there are only a few reports demonstrating the feasibility of this approach4. However, we have recently established a platform that used iPSC-derived hepatocytes to successfully identify drugs that can be repurposed for the treatment of deficiencies in liver metabolism5.
This protocol explains the process of differentiating human iPSCs to hepatocyte-like cells in 96-well plates and using them to screen a library of small molecules. It also describes the endpoint analysis using hypercholesterolemia as an example of metabolic liver disease. This approach should be useful to study the role and application of small molecules in the context of infectious liver disease, metabolic liver disease, drug toxicity, and other liver disorders.

<table border="0" cellpadding="0" cellspacing="0" width="959">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:588px;">100 mm x 20 mm sterile tissue culture dishes&#160;</td>
			<td style="width:164px;">Corning</td>
			<td style="width:119px;">430167</td>
			<td style="width:88px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">100 mm x 20 mm sterile suspension culture dishes</td>
			<td>Corning</td>
			<td>430591</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">96-wells tissue culture plate&#160;</td>
			<td>Corning</td>
			<td>3595</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-human Albumin</td>
			<td>Dako</td>
			<td>A 0001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-human FOXA2(6C12)</td>
			<td>Novus Biological</td>
			<td>H00003170-M12</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-human HNF4 alpha</td>
			<td>Santa Cruz</td>
			<td>SC-6556</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-human Oct-3/4 antibody</td>
			<td>Santa Cruz</td>
			<td>SC-9081</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-human SOX17</td>
			<td>R&#38;D</td>
			<td>AF1924</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-human TRA-1-60 FITC conjugated</td>
			<td>Millipore</td>
			<td>FCMAB115F</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Activin A Recombinant Human Protein&#160;</td>
			<td>Invitrogen</td>
			<td>PHC9563</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">B-27 Supplement, minus insulin&#160;</td>
			<td>Invitrogen</td>
			<td>0050129SA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">B-27 Supplement, serum free&#160;</td>
			<td>Invitrogen</td>
			<td>17504044</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">BMP4 Recombinant Human Protein&#160;</td>
			<td>Invitrogen</td>
			<td>PHC9533</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cell Dissociation Reagent StemPro&#160; Accutase&#160;</td>
			<td>Invitrogen</td>
			<td>A1110501</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">CellTiter-Glo Luminescent Cell Viability Assay&#160;</td>
			<td>Promega</td>
			<td>7572</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DPBS+(calcium, magnesium)</td>
			<td>Invitrogen</td>
			<td>14040-133</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DPBS-(no calcium, no magnesium)</td>
			<td>Invitrogen</td>
			<td>14190-144</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DMEM/F-12, HEPES&#160;</td>
			<td>Invitrogen</td>
			<td>11330057</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ELISA human APOB ELISA development kit</td>
			<td>Mabtech</td>
			<td>3715-1H-20</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fibroblast Growth Factor 2 (FGF2)</td>
			<td>Invitrogen</td>
			<td>PHG0023</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hepatocyte Culture Medium (HCM Bullet Kit)&#160;</td>
			<td>Lonza</td>
			<td>CC-3198</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hepatocyte Growth Factor&#160; (HGF)</td>
			<td>Invitrogen</td>
			<td>PHC0321</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">L-Glutamine&#160;</td>
			<td>Invitrogen</td>
			<td>25030081</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">MEM Non-Essential Amino Acids Solution</td>
			<td>Invitrogen</td>
			<td>11140076</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Oncostatin M (OSM) Recombinant Human Protein&#160;</td>
			<td>Invitrogen</td>
			<td>PHC5015</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Penicillin-Streptomycin&#160;</td>
			<td>Invitrogen</td>
			<td>15140163</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Feeder free pluripotent stem cell medium: mTesR1&#160;</td>
			<td>STEMCELL technologies</td>
			<td>5850</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Reduced Growth Factor Basement Membrane Matrix&#160;</td>
			<td>Invitrogen</td>
			<td>A1413301</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RPMI 1640 Medium, HEPES&#160;</td>
			<td>Invitrogen</td>
			<td>22400105</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">StemAdhere Defined Matrix for hPSC (E-cad-Fc)</td>
			<td>Primorigen Biosciences</td>
			<td>S2071</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">TMB-ELISA Substrate Solution</td>
			<td>Thermo Scientific&#160;</td>
			<td>34022</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-TRA-1-60 FITC conjugated</td>
			<td>Millipore</td>
			<td>FCMAB115F</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Versene (EDTA) 0.02%&#160;</td>
			<td>Lonza</td>
			<td>17-711E</td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Y-27632 ROCK inhibitor</td>
			<td>STEMCELL Technologies</td>
			<td>72302</td>
			<td></td>
		</tr>
	</tbody>
</table>

using human induced pluripotent stem cell-derived hepatocyte-like cells for drug discovery

The ability to differentiate human induced pluripotent stem cells (iPSCs) into hepatocyte-like cells (HLCs) provides new opportunities to study inborn errors in hepatic metabolism. However, to provide a platform that supports the identification of small molecules that can potentially be used to treat liver disease, the procedure requires a culture format that is compatible with screening thousands of compounds. Here, we describe a protocol using completely defined culture conditions, which allow the reproducible differentiation of human iPSCs to hepatocyte-like cells in 96-well tissue culture plates. We also provide an example of using the platform to screen compounds for their ability to lower Apolipoprotein B (APOB) produced from iPSC-derived hepatocytes generated from a familial hypercholesterolemia patient. The availability of a platform that is compatible with drug discovery should allow researchers to identify novel therapeutics for diseases that affect the liver.

Generation of hepatocyte-like cells: Figure 1 describes the timeframe of the changes that occur during the differentiation of human iPSCs to hepatocyte-like cells. The culture of iPSCs on E-Cad-Fc provides approximately 2 mm diameter colonies that express the pluripotent marker OCT4 (Figure 1A-B). The morphology of the cells grown on an E-cadherin matrix will be ...

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Using Human Induced Pluripotent Stem Cell-derived Hepatocyte-like Cells for Drug Discovery

The protocol presented here describes a platform for identifying small molecules for the treatment of liver disease. A step-by-step description is presented detailing how to differentiate iPSCs into cells with hepatocyte characteristics in 96-well plates, and to use the cells to screen for small molecules with potential therapeutic activity.

The ability to differentiate human induced pluripotent stem cells (iPSCs) into hepatocyte-like cells (HLCs) provides new opportunities to study inborn ...

The overall goal of this experiment is to differentiate human induced pluripotent stem cells into hepatocytes-like cells in a manner that is suitable for high-throughput screening. Liver cells are difficult to grow in the laboratory, however they can be generated from induced pluripotent stem cells which provides a screening platform to identify treatments for liver disease. The main advantage of this technique is that unlimited numbers of hepatocytes can be generated from any patient with liver disease that recapitulate the disease in the laboratory.The procedure is relatively easy to establish, even without extensive knowledge of stem cell biology. Its reproducibility allows researchers to screen thousands of compounds without a need for complex robotics. Ray Liu, a postdoctoral fellow, and Paige Lamprecht, a graduate student, will be demonstrating the procedure today.First, dilute the fusion protein Ecad to 15 micrograms per milliliter with Dulbecco's phosphate-buffered saline, or DPBS, that contains calcium and magnesium. Coat 100 millimeter suspension tissue culture dishes with five milliliters of diluted matrix and incubate at 37 degrees Celsius for at least one hour. Following incubation, remove the substrate, and replace with five milliliters of iPSC culture medium.Retrieve a vial of cryopreserved human induced pluripotent stem cells from liquid nitrogen. Thaw at 37 degrees Celsius until a small ice crystal remains. Then, gently pipette the cells into a sterile 15 milliliter conical tube containing four milliliters of the culture medium.Centrifuge the cells at 300 G for five minutes. Remove the supernatant and gently re-suspend the cells with five milliliters of medium supplemented with ten micromolar of Y-27632, a selective inhibitor of a Rho-associated, coiled-coil-containing protein kinase. Now, remove the culture medium from the Ecad-coated ten millimeter suspension tissue culture dishes and add five milliliters of the cells.Once the iPSCs reach around 80%confluency, remove the culture medium and wash once with calcium and magnesium-free DPBS. Aspirate the DPBS and add a sufficient amount of 0.02%EDTA solution to cover the dishes. Then, incubate the cells for up to three minutes at room temperature.As soon as the cells begin to release, remove the 0.02%EDTA solution and flood the dish with ten milliliters of M medium to release the cells. Aid the detachment of iPSCs by gentle pipetting. Transfer 1/10th of the suspended cells per fresh Ecad-coated tissue culture dish containing five milliliters of M medium.Incubate the cultures at 37 degrees Celsius under 4%oxygen and 5%carbon dioxide, changing the medium daily. Retrieve one vial of 250 microliters of ice-cold matrix stock with concentration of two milligrams per milliliter and thaw it on ice. Next, combine the thawed matrix with ten milliliters of cold DMEM/F12 by mixing gently using a pre-chilled pipette to make a final concentration of 0.05 milligrams per milliliter.Transfer 100 microliters of the diluted matrix to each well of a 96-well tissue culture plate. Incubate the plate at 37 degrees Celsius under 4%oxygen and 5%carbon dioxide for at least one hour. Following incubation, discard the matrix and replace with 50 microliters of M medium per well, repeating the same coating procedure with the rest of the plates.Now, culture the iPSCs on 100 millimeter dishes until the cells approach 80%confluency. To harvest the iPSCs from each 100 millimeter plate, aspirate the culture medium and rinse with five milliliters of DPBS. Replace the rinse with three milliliters of cell detachment solution, such as Accutase.Then, incubate for around two minutes at 37 degrees Celsius under 4%oxygen and 5%carbon dioxide. As soon as the cells begin to detach, harvest by adding seven milliliters of M medium. Pipette several times to dissociate the cell colonies into small clusters of around three to six cells.Next, collect the iPSCs into a 15 milliliter sterile centrifuge tube and centrifuge at 300 G for five minutes. When finished, remove the supernatant and re-suspend the cell pellet in five milliliters of M medium. Evenly distribute the cells onto 96-well matrix-coated plates by pipetting 50 microliters of suspension cells into each well using a multi-channel pipette.Then, culture the cells overnight at 37 degrees Celsius under 4%oxygen and 5%carbon dioxide and repeat the cell seeding procedures with the rest of the plates. Examine the 96-well plates by microscopy to insure that cells cover at least 70%of the surface of each individual well. For day one to day two of differentiation, replace the culture medium with 100 microliters of RPMI-based differentiation medium per well.Then, incubate the cells at 37 degrees Celsius in ambient oxygen and 5%carbon dioxide for two days with a daily medium change. For day three to day five of differentiation, replace the culture medium with 100 microliters of RPMI-based differentiation medium supplemented with 2%B27 and 100 nanograms per milliliter of active NA.Culture the cells at 37 degrees Celsius in ambient oxygen and 5%carbon dioxide for three days with a daily medium change. At differentiation day five, treat each well with 100 microliters of 0.02%EDTA solution for 30 seconds and remove the solution immediately.Add 100 microliters of fresh RPMI-based differentiation medium and repeat the same procedure for the rest of the plates. For differentiation between days six to ten, replace the culture medium with 100 microliters of RPMI-based differentiation medium. Incubate the cells at 37 degrees Celsius under 4%oxygen and 5%carbon dioxide for five days with a daily medium change.For differentiation between days 11 to 15, replace the culture medium with 100 microliters of RPMI-based differentiation medium, supplemented with 2%B27 and 20 nanograms per milliliter of HGF. Incubate the cells at 37 degrees Celsius under 4%oxygen and 5%carbon dioxide for five days with a daily medium change. For differentiation between days 16 to 20, replace the culture medium with a hepatocyte cell culture medium supplemented with 20 nanograms per milliliter of oncostatin-M.Incubate the cells at 37 degrees Celsius in ambient oxygen and 5%carbon dioxide for five days with a daily medium change. At the completion of differentiation on day 20, replace the culture medium with 100 microliters of fresh hepatocyte cell culture medium supplemented with 20 nanograms per milliliter of oncostatin-M. After incubating for 24 hours, retrieve the culture medium into a fresh 96-well plate and store at 20 degrees Celsius.Repeat the same collection procedure for the rest of the plates. Add 90 microliters of fresh hepatocyte cell culture medium supplemented with oncostatin-M into each well of the 96-well plate. Add ten microliters of each chosen compound from a previously prepared working stock solution.Add DMSO to 0.2%to the control wells to match the final concentration in the treated samples. After incubating for 24 hours, collect the culture medium into a fresh 96-well plate and store at 20 degrees Celsius. Repeat the same collection procedure for the rest of the plates.After five days of treatment, the cells express proteins that are characteristically expressed in the Definitive Endoderm. After five more days of differentiation, the Endoderm converts to a hepatic fate, and the cells express FOXA2 and HNF 4a. After HGF addition, the cells express proteins found in fetal hepatocytes, and at completion of differentiation, the cells adopt a cuboidal morphology with a nucleus containing prominent nucleoli and a large cytoplasm with multiple lipid droplets.Immunostaining to detect HNF 4a and albumin at day 20 of differentiation shows that the distribution of these hepatocyte proteins is similar across all wells. iPSCs were used to screen for APOB-lowering compounds to provide an example of using iPSC-derived hepatocytes for small molecule screening. The z-factor of the APOB assay is 0.73, which confirms the suitability of using the platform for drug discovery.The post-drug, pre-drug ratio of APOB was determined for each compound. An identification of hits was achieved by z-score analysis. 24 potential hits with an APOB ratio from 0.86 to 0.44 were identified.After excluding compounds that had a negative impact on cell viability, two compounds were found to be reproducible for lowering APOB. Once mastered, this technique can be done in 25 days if it is performed properly. While attempting this procedure, it is important to remember to prepare fresh medium daily.Incorrect concentration of components due to degradation will change the ability to cells to differentiate. After its development, this technique paved the way for researchers in the field of drug discovery to explore therapeutic treatment for liver disease using human induced pluripotent stem cells. After watching this video, you should have a good understanding of how to culture and maintain human induced pluripotent stem cells and to perform hepatic differentiation in a small surface pressed form for high-throughput screening.Don't forget that working with human induced pluripotent stem cells can be extremely hazardous and the personal protective equipment, such as gloves and a lab coat, should always be worn while performing this procedure.

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Research

JoVE Journal

Developmental Biology

Generation of Integration-free Human Induced Pluripotent Stem Cells Using Hair-derived Keratinocytes

Recent advances in reprogramming allow us to turn somatic cells into human induced pluripotent stem cells (hiPSCs). Disease modeling using patient-specific hiPSCs allows the study of the underlying mechanism for pathogenesis, also providing a platform for the development of in vitro drug screening and gene therapy to improve treatment options. The promising potential of hiPSCs for regenerative medicine is also evident from the increasing number of publications (>7000) on iPSCs in recent years. Various cell types from distinct lineages have been successfully used for hiPSC generation, including skin fibroblasts, hematopoietic cells and epidermal keratinocytes. While skin biopsies and blood collection are routinely performed in many labs as a source of somatic cells for the generation of hiPSCs, the collection and subsequent derivation of hair keratinocytes are less commonly used. Hair-derived keratinocytes represent a non-invasive approach to obtain cell samples from patients. Here we outline a simple non-invasive method for the derivation of keratinocytes from plucked hair. We also provide instructions for maintenance of keratinocytes and subsequent reprogramming to generate integration-free hiPSC using episomal vectors.

This manuscript provides a step-by-step procedure for the derivation and maintenance of human keratinocytes from plucked hair and subsequent generation of integration-free human induced pluripotent stem cells (hiPSCs) by episomal vectors.

Recent advances in reprogramming allow us to turn somatic cells into human induced pluripotent stem cells (hiPSCs). Disease modeling using ...

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.

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

Pluripotent Stem Cell Derived Cardiac Cells for Myocardial Repair

Human induced pluripotent stem cells (hiPSCs) must be fully differentiated into specific cell types before administration, but conventional protocols for differentiating hiPSCs into cardiomyocytes (hiPSC-CMs), endothelial cells (hiPSC-ECs), and smooth muscle cells (SMCs) are often limited by low yield, purity, and/or poor phenotypic stability. Here, we present novel protocols for generating hiPSC-CMs, -ECs, and -SMCs that are substantially more efficient than conventional methods, as well as a method for combining cell injection with a cytokine-containing patch created over the site of administration. The patch improves both the retention of the injected cells, by sealing the needle track to prevent the cells from being squeezed out of the myocardium, and cell survival, by releasing insulin-like growth factor (IGF) over an extended period. In a swine model of myocardial ischemia-reperfusion injury, the rate of engraftment was more than two-fold greater when the cells were administered with the cytokine-containing patch comparing to the cells without patch, and treatment with both the cells and the patch, but not with the cells alone, was associated with significant improvements in cardiac function and infarct size.

We present three novel and more efficient protocols for differentiating human induced pluripotent stem cells into cardiomyocytes, endothelial cells, and smooth muscle cells and a delivery method that improves the engraftment of transplanted cells by combining cell injection with patch-mediated cytokine delivery.

Human induced pluripotent stem cells (hiPSCs) must be fully differentiated into specific cell types before administration, but conventional protocols for ...

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.

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

Integration Free Derivation of Human Induced Pluripotent Stem Cells Using Laminin 521 Matrix

Xeno-free and fully defined conditions are key parameters for robust and reproducible generation of homogenous human induced pluripotent stem (hiPS) cells. Maintenance of hiPS cells on feeder cells or undefined matrices are susceptible to batch variances, pathogenic contamination and risk of immunogenicity. Utilizing the defined recombinant human laminin 521 (LN-521) matrix in combination with xeno-free and defined media formulations reduces variability and allows for the consistent generation of hiPS cells. The Sendai virus (SeV) vector is a non-integrating RNA-based system, thus circumventing concerns associated with the potential disruptive effect on genome integrity integrating vectors can have. Furthermore, these vectors have demonstrated relatively high efficiency in the reprogramming of dermal fibroblasts. In addition, enzymatic single cell passaging of cells facilitates homogeneous maintenance of hiPS cells without substantial prior experience of stem cell culture. Here we describe a protocol that has been extensively tested and developed with a focus on reproducibility and ease of use, providing a robust and practical way to generate defined and xeno-free human hiPS cells from fibroblasts.

Robust derivation of human induced pluripotent stem (hiPS) cells was achieved by using non-integrating Sendai virus (SeV) vector mediated reprogramming of dermal fibroblasts. hiPS cell maintenance and clonal expansion was performed using xeno-free and chemically defined culture conditions with recombinant human laminin 521 (LN-521) matrix and Essential E8 (E8) Medium.

Xeno-free and fully defined conditions are key parameters for robust and reproducible generation of homogenous human induced pluripotent stem (hiPS) ...

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.

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

A Familial Hypercholesterolemia Human Liver Chimeric Mouse Model Using Induced Pluripotent Stem Cell-derived Hepatocytes

Familial hypercholesterolemia (FH) is mostly caused by low-density lipoprotein receptor (LDLR) mutations and results in an increased risk of early-onset cardiovascular disease due to marked elevation of LDL cholesterol (LDL-C) in blood. Statins are the first line of lipid-lowering drugs for treating FH and other types of hypercholesterolemia, but new approaches are emerging, in particular PCSK9 antibodies, which are now being tested in clinical trials. To explore novel therapeutic approaches for FH, either new drugs or new formulations, we need appropriate in vivo models. However, differences in the lipid metabolic profiles compared to humans are a key problem of the available animal models of FH. To address this issue, we have generated a human liver chimeric mouse model using FH induced pluripotent stem cell (iPSC)-derived hepatocytes (iHeps). We used Ldlr-/-/Rag2-/-/Il2rg-/- (LRG) mice to avoid immune rejection of transplanted human cells and to assess the effect of LDLR-deficient iHeps in an LDLR null background. Transplanted FH iHeps could repopulate 5-10% of the LRG mouse liver based on human albumin staining. Moreover, the engrafted iHeps responded to lipid-lowering drugs and recapitulated clinical observations of increased efficacy of PCSK9 antibodies compared to statins. Our human liver chimeric model could thus be useful for preclinical testing of new therapies to FH. Using the same protocol, similar human liver chimeric mice for other FH genetic variants, or mutations corresponding to other inherited liver diseases, may also be generated.

Here, we present a protocol to generate a human liver chimeric mouse model of familial hypercholesterolemia using human induced pluripotent stem cell-derived hepatocytes. This is a valuable model for testing new therapies for hypercholesterolemia.

Familial hypercholesterolemia (FH) is mostly caused by low-density lipoprotein receptor (LDLR) mutations and results in an increased risk of early-onset ...

Semi-automated Production of Hepatocyte Like Cells from Pluripotent Stem Cells

Human pluripotent stem cells represent a renewable source of human tissue. Our research is focused on generating human liver tissue from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs). Current differentiation procedures generate human hepatocyte-like cells (HLCs) displaying a mixture of fetal and adult traits. To improve cell phenotype, we have fully defined our differentiation procedure and the cell niche, resulting in the generation of cell populations which display improved gene expression and&#160;function. While these studies mark progress, the ability to generate large quantities of multi well plates for screening has been limited by labour intensive procedures and batch to batch variation. To tackle this issue, we have developed a semi-automated platform to differentiate pluripotent stem cells into HLCs. Stem cell seeding and differentiation were performed using liquid handling and automatic pipetting systems in&#160;96-well plate format. Following the differentiation, cell phenotype was analyzed using automated microscopy and a multi well luminometer.

This protocol describes a semi-automated approach to produce hepatocyte-like cells from human pluripotent stem cells in a 96 well plate format. This process is rapid and cost-effective, allowing the production of quality assured batches of hepatocyte-like cells for basic and applied human research.

Human pluripotent stem cells represent a renewable source of human tissue. Our research is focused on generating human liver tissue from human embryonic ...

Microfluidic Assay for the Assessment of Leukocyte Adhesion to Human Induced Pluripotent Stem Cell-derived Endothelial Cells (hiPSC-ECs)

Endothelial cells (ECs) are essential for the regulation of inflammatory responses by either limiting or facilitating leukocyte recruitment into affected tissues via a well-characterized cascade of pro-adhesive receptors which are upregulated on the leukocyte cell surface upon the inflammatory trigger. Inflammatory responses differ between individuals in the population and the genetic background can contribute to these differences. Human induced pluripotent stem cells (hiPSCs) have been shown to be a reliable source of ECs (hiPSC-ECs), thus representing an unlimited source of cells that capture the genetic identity and any genetic variants or mutations of the donor. hiPSC-ECs can therefore be used for modeling inflammatory responses in donor-specific cells. Inflammatory responses can be modeled by determining leukocyte adhesion to the hiPSC-ECs under physiological flow. This step-by-step protocol provides a detailed description of the experimental setup and data analysis for the assessment of inflammatory responses in hiPSC-ECs and the analysis of leukocyte adhesion under physiological flow.

Microfluidic Assay for the Assessment of Leukocyte Adhesion to Human Induced Pluripotent Stem Cell-derived Endothelial Cells hiPSC-ECs

This step-by-step protocol provides a detailed description of the experimental setup and data analysis for the assessment of inflammatory responses in hiPSC-ECs and the analysis of leukocyte adhesion under physiological flow.

Endothelial cells (ECs) are essential for the regulation of inflammatory responses by either limiting or facilitating leukocyte recruitment into affected ...

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.

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