Tang and Weintraub were partially supported by NIH-AR070029, NIH-HL086555, NIH-HL134354.

All animal handling and surgical procedures were performed by a protocol approved by the Augusta University Institutional Animal Care and Use Committee (IACUC). Mice were fed standard diet and water ad libitum.
1. Isolation of primary mouse &#64257;broblasts from adult Dmdmdx mice
<ol>
	<li>Euthanize adult Dmdmdx mice (male, 2 months old) by CO2 asphyxiation and thoracotomy according to IACUC approved by Medical College of Georgia, Augusta University. Cut the...

<ol>
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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sparks,+signals+and+shock+absorbers:+how+dystrophin+loss+causes+muscular+dystrophy.">Sparks, signals and shock absorbers: how dystrophin loss causes muscular dystrophy.</a> Trends Cell Biology. 16 (4), 198-205 (2006).</li><li>Gregorevic, P., 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=Systemic+delivery+of+genes+to+striated+muscles+using+adeno-associated+viral+vectors.">Systemic delivery of genes to striated muscles using adeno-associated viral vectors.</a> Nature Medicine. 10 (8), 828-834 (2004).</li><li>Bengtsson, N. E., Seto, J. T., Hall, J. K., Chamberlain, J. S., Odom, G. 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E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+genome+editing+improves+muscle+function+in+a+mouse+model+of+Duchenne+muscular+dystrophy.">In vivo genome editing improves muscle function in a mouse model of Duchenne muscular dystrophy.</a> Science. 351 (6271), 403-407 (2016).</li><li>Long, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prevention+of+muscular+dystrophy+in+mice+by+CRISPR/Cas9-mediated+editing+of+germline+DNA.">Prevention of muscular dystrophy in mice by CRISPR/Cas9-mediated editing of germline DNA.</a> Science. 345 (6201), 1184-1188 (2014).</li><li>El Refaey, 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=In+Vivo+Genome+Editing+Restores+Dystrophin+Expression+and+Cardiac+Function+in+Dystrophic+Mice.">In Vivo Genome Editing Restores Dystrophin Expression and Cardiac Function in Dystrophic Mice.</a> Circulation Research. 121 (8), 923-929 (2017).</li><li>Amoasii, 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=Gene+editing+restores+dystrophin+expression+in+a+canine+model+of+Duchenne+muscular+dystrophy.">Gene editing restores dystrophin expression in a canine model of Duchenne muscular dystrophy.</a> Science. 362 (6410), 86-91 (2018).</li><li>Eisen, 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=Electrophysiological+abnormalities+in+induced+pluripotent+stem+cell-derived+cardiomyocytes+generated+from+Duchenne+muscular+dystrophy+patients.">Electrophysiological abnormalities in induced pluripotent stem cell-derived cardiomyocytes generated from Duchenne muscular dystrophy patients.</a> Journal of Cellular and Molecular Medicine. 23 (3), 2125-2135 (2019).</li><li>Marion, R. 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=Telomeres+acquire+embryonic+stem+cell+characteristics+in+induced+pluripotent+stem+cells.">Telomeres acquire embryonic stem cell characteristics in induced pluripotent stem cells.</a> Cell Stem Cell. 4 (2), 141-154 (2009).</li><li>Dumont, N. 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=Dystrophin+expression+in+muscle+stem+cells+regulates+their+polarity+and+asymmetric+division.">Dystrophin expression in muscle stem cells regulates their polarity and asymmetric division.</a> Nature Medicine. 21 (12), 1455-1463 (2015).</li><li>Sacco, 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=Short+telomeres+and+stem+cell+exhaustion+model+Duchenne+muscular+dystrophy+in+mdx/mTR+mice.">Short telomeres and stem cell exhaustion model Duchenne muscular dystrophy in mdx/mTR mice.</a> Cell. 143 (7), 1059-1071 (2010).</li><li>Su, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+and+Transplantation+of+Myogenic+Progenitor+Cell+Derived+Exosomes+to+Improve+Cardiac+Function+in+Duchenne+Muscular+Dystrophic+Mice.">Purification and Transplantation of Myogenic Progenitor Cell Derived Exosomes to Improve Cardiac Function in Duchenne Muscular Dystrophic Mice.</a> Journal of Visualized Experiments. (146), (2019).</li><li>Su, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exosome-Derived+Dystrophin+from+Allograft+Myogenic+Progenitors+Improves+Cardiac+Function+in+Duchenne+Muscular+Dystrophic+Mice.">Exosome-Derived Dystrophin from Allograft Myogenic Progenitors Improves Cardiac Function in Duchenne Muscular Dystrophic Mice.</a> Journal of Cardiovascular Translational Research. 11 (5), 412-419 (2018).</li><li>Ousterout, D. G., 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=Multiplex+CRISPR/Cas9-based+genome+editing+for+correction+of+dystrophin+mutations+that+cause+Duchenne+muscular+dystrophy.">Multiplex CRISPR/Cas9-based genome editing for correction of dystrophin mutations that cause Duchenne muscular dystrophy.</a> Nature Communications. 6, 6244 (2015).</li><li>Barde, I., 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+control+of+gene+expression+in+the+hematopoietic+system+using+a+single+Tet-on+inducible+lentiviral+vector.">Efficient control of gene expression in the hematopoietic system using a single Tet-on inducible lentiviral vector.</a> Molecular Therapy. 13 (2), 382-390 (2006).</li><li>Glass, K. 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Duchenne Muscular Dystrophy (DMD) is a destructive and ultimately fatal hereditary disease characterized by a lack of dystrophin, leading to progressive muscle atrophy1,2. Our results demonstrate the restored dystrophin gene expression in Dmdmdx iPSC-derived myogenic progenitor cells by the approach of CRISPR/Cas9-mediated exon23 deletion. This approach has three advantages.
First, we generated iPSCs from Dmdmdx m...

Duchenne muscular dystrophy (DMD) is one of the most common muscular dystrophies and is characterized by the absence of dystrophin, affecting 1 of approximately 5,000 newborn boys worldwide1. Loss of dystrophin gene function results in structural muscle defects leading to progressive myofibers degeneration1,2. Recombinant adeno-associated virus (rAAV)-mediated gene therapy system has been tested to restore the dystrophin expression and improve muscle function, such as gene replacement using micro-dystrophins (&#181;-Dys). However, the rAAV approach requires repeated injections to sustain expression of the functional protein3,4. Therefore, we need a strategy that can provide effectively and permanently recover dystrophin gene expression in patients with DMD. The&#160;Dmdmdx mouse, a mouse model for DMD, has a point mutation in exon 23 of the&#160;dystrophin&#160;gene that introduces a premature termination codon and results in a non-functional truncated protein lacking the C-terminal dystroglycan binding domain. Recent studies demonstrated the use of CRISPR/Cas9 technology to restore dystrophin gene expression by accurate gene correction or mutant exon deletion in small and large animal5,6,7. Long et al.8 reported the method for correcting the dystrophin gene mutation in Dmdmdx mouse germline by homology-directed repair (HDR) based CRISPR/Cas9 genome editing. El Refaey et al.9 reported that rAAV could efficiently excise the mutant exon 23 in dystrophic mice. In these studies, gRNAs were designed in the introns 20 and 23 to cause double-stranded DNA breaks, which partially restored the dystrophin expression after DNA repair via non-homologous end joining (NHEJ). Even more exciting, Amoasii et al.10 recently reported the efficacy and feasibility of rAAV-mediated CRISPR gene editing in restoring dystrophin expression in canine models, an essential step in future clinical application.
DMD also causes stem cell disorders11. For muscle damage, residential muscle stem cells replenish dying muscle cells after muscle differentiation. However, the consecutive cycles of injury and repair lead to shortening of telomeres in muscle stem cells12, and premature depletion of stem cell pools13,14. Therefore, a combination of autologous stem cell therapy with genome editing to restore dystrophin expression can be a practical approach for treating DMD. The CRISPR/Cas9 technology provides the possibility of generating autologous genetically corrected induced pluripotent stem cells (iPSC) for functional muscle regeneration and prevent further complications of DMD without causing immune rejection. However, iPSCs have a risk of tumor formation, which could be alleviated by the differentiation of iPSC into myogenic progenitor cells.
In this protocol, we describe the use of non-integrating Sendai virus to reprogramming dermal fibroblasts of Dmdmdx mice into iPSCs and then recover dystrophin expression by CRISPR/Cas9 genome deletion. After validation of Exon23 deletion in iPSC by genotyping, we differentiated genome-corrected iPSC into myogenic progenitors (MPC) via MyoD-induced myogenic differentiation.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Surgical Instruments</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>31-gauge needle</td>
			<td>Various&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sharp Incision</td>
			<td>Various&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile Scalpels</td>
			<td>Various&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Tweezers</td>
			<td>Various&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fibroblast medium (for 100 mL of complete medium)</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Volume</td>
		</tr>
		<tr>
			<td>2-Mercaptoethanol (55 mM)</td>
			<td>Gibco</td>
			<td>21-985-023</td>
			<td>0.1 mL</td>
		</tr>
		<tr>
			<td>Antibiotic Antimycotic Slution 100x</td>
			<td>CORNING</td>
			<td>MT30004CI</td>
			<td>1 mL</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Modified Eagle&#39;s Medium - high glucose</td>
			<td>SIGMA</td>
			<td>D6429</td>
			<td>87 mL</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum Characterized</td>
			<td>HyClone</td>
			<td>SH30396.03</td>
			<td>10 mL</td>
		</tr>
		<tr>
			<td>L-Glutamine solution</td>
			<td>SIGMA</td>
			<td>G7513</td>
			<td>1 mL</td>
		</tr>
		<tr>
			<td>MEM Non-Essential Amino Acids Solution (100x)&#160;</td>
			<td>Gibco</td>
			<td>11140076</td>
			<td>1 mL</td>
		</tr>
		<tr>
			<td>TVP solution (for 500 mL of complete solution)</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Volume</td>
		</tr>
		<tr>
			<td>Chicken Serum</td>
			<td>Gibco</td>
			<td>16110-082</td>
			<td>5 mL</td>
		</tr>
		<tr>
			<td>EDTA</td>
			<td>Sigma-Aldrich</td>
			<td>E6758</td>
			<td>186 mg</td>
		</tr>
		<tr>
			<td>Phosphat-buffered saline</td>
			<td></td>
			<td></td>
			<td>to 500 mL</td>
		</tr>
		<tr>
			<td>Trypsin (2.5%)</td>
			<td>Thermo</td>
			<td>15090046</td>
			<td>5 mL</td>
		</tr>
		<tr>
			<td>mES growth medium(for 500 mL of complete solution)</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Volume</td>
		</tr>
		<tr>
			<td>2-Mercaptoethanol (55 mM)</td>
			<td>Gibco</td>
			<td>21-985-023</td>
			<td>0.5 mL</td>
		</tr>
		<tr>
			<td>Antibiotic Antimycotic Slution 100x</td>
			<td>CORNING</td>
			<td>MT30004CI</td>
			<td>5 mL</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Modified Eagle&#39;s Medium - high glucose</td>
			<td>SIGMA</td>
			<td>D6429</td>
			<td>408.5 mL</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum Characterized</td>
			<td>HyClone</td>
			<td>SH30396.03</td>
			<td>75 mL</td>
		</tr>
		<tr>
			<td>L-Glutamine solution</td>
			<td>SIGMA</td>
			<td>G7513</td>
			<td>5 mL</td>
		</tr>
		<tr>
			<td>Mouse recombinant Leukemia Inhibitory Factor (LIF), 0.5 x 106 U/mL</td>
			<td>EMD Millipore Corp</td>
			<td>CS210511</td>
			<td>500 &#956;L</td>
		</tr>
		<tr>
			<td>MEK/GS3 Inhibitor Supplement</td>
			<td>EMD Millipore Corp</td>
			<td>CS210510-500UL</td>
			<td>500 &#956;L</td>
		</tr>
		<tr>
			<td>MEM Non-Essential Amino Acids Solution (100x)&#160;</td>
			<td>Gibco</td>
			<td>11140076</td>
			<td>5 mL</td>
		</tr>
		<tr>
			<td colspan="4">The ES cell media should not be stored for more than 4 weeks and with inhibitors not more than 2 weeks.</td>
		</tr>
		<tr>
			<td>mES frozen medium(for 50 mL of complete solution)</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Volume</td>
		</tr>
		<tr>
			<td>Dimethyl sulfoxide (DMSO)</td>
			<td>SIGMA</td>
			<td>D2650</td>
			<td>5 mL</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Modified Eagle&#39;s Medium - high glucose</td>
			<td>SIGMA</td>
			<td>D6429</td>
			<td>24.9 mL</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum Characterized</td>
			<td>HyClone</td>
			<td>SH30396.03</td>
			<td>25 mL</td>
		</tr>
		<tr>
			<td>Mouse recombinant Leukemia Inhibitory Factor (LIF), 0.5 x 106 U/mL</td>
			<td>EMD Millipore Corp</td>
			<td>CS210511</td>
			<td>50 &#956;L</td>
		</tr>
		<tr>
			<td>Name of Material/ Equipment</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>RRID</td>
		</tr>
		<tr>
			<td>0.05% Trypsin/0.53 mM EDTA</td>
			<td>CORNING</td>
			<td>25-052-CI</td>
			<td></td>
		</tr>
		<tr>
			<td>4% Paraformaldehyde</td>
			<td>Thermo scientific</td>
			<td>J19943-k2</td>
			<td></td>
		</tr>
		<tr>
			<td>Accutase solution</td>
			<td>SIGMA</td>
			<td>A6964</td>
			<td>Cell detachment solution</td>
		</tr>
		<tr>
			<td>AgeI-HF</td>
			<td>NEB</td>
			<td>R3552L</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa488-conjugated goat-anti-mouse antibody</td>
			<td>Invitrogen</td>
			<td>A32723</td>
			<td>AB_2633275</td>
		</tr>
		<tr>
			<td>Alexa488-conjugated goat-anti-rabbit antibody</td>
			<td>Invitrogen</td>
			<td>A32731</td>
			<td>AB_2633280</td>
		</tr>
		<tr>
			<td>Alexa555-conjugated goat-anti-rabbit antibody</td>
			<td>Invitrogen</td>
			<td>A32732</td>
			<td>AB_2633281</td>
		</tr>
		<tr>
			<td>anti-AFP</td>
			<td>Thermo scientific</td>
			<td>RB-365-A1</td>
			<td>AB_59574</td>
		</tr>
		<tr>
			<td>anti-&#945;-Smooth Muscle Actin (D4K9N) XP</td>
			<td>CST</td>
			<td>19245S</td>
			<td>AB_2734735</td>
		</tr>
		<tr>
			<td>anti-Dystrophin</td>
			<td>Thermo</td>
			<td>PA5-32388</td>
			<td>AB_2549858</td>
		</tr>
		<tr>
			<td>anti-LIN28A (D1A1A) XP&#160;&#160;&#160;</td>
			<td>CST</td>
			<td>8641S</td>
			<td>AB_10997528</td>
		</tr>
		<tr>
			<td>anti-MYH2</td>
			<td>DSHB</td>
			<td>mAb2F7</td>
			<td>AB_1157865</td>
		</tr>
		<tr>
			<td>anti-Nanog-XP</td>
			<td>CST</td>
			<td>8822S</td>
			<td>AB_11217637</td>
		</tr>
		<tr>
			<td>anti-Oct-4A (D6C8T)</td>
			<td>CST</td>
			<td>83932S</td>
			<td>AB_2721046</td>
		</tr>
		<tr>
			<td>anti-Sox2</td>
			<td>abcam</td>
			<td>ab97959</td>
			<td>AB_2341193</td>
		</tr>
		<tr>
			<td>anti-SSEA1(MC480)&#160;</td>
			<td>CST</td>
			<td>4744s</td>
			<td>AB_1264258</td>
		</tr>
		<tr>
			<td>anti-TH (H-196)</td>
			<td>SANTA CRUZ&#160;</td>
			<td>sc-14007</td>
			<td>AB_671397</td>
		</tr>
		<tr>
			<td>Alkaline Phosphatase Live Stain (500x)</td>
			<td>Thermo</td>
			<td>A14353</td>
			<td></td>
		</tr>
		<tr>
			<td>Blasticidin S</td>
			<td>Sigma-Aldrich</td>
			<td>203350</td>
			<td></td>
		</tr>
		<tr>
			<td>BsmBI/Esp3I</td>
			<td>NEB</td>
			<td>R0580L/R0734L</td>
			<td></td>
		</tr>
		<tr>
			<td>Carbenicillin</td>
			<td>Millipore</td>
			<td>205805-250MG</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase IV&#160;</td>
			<td>Worthington Biochemical Corporation</td>
			<td>LS004189</td>
			<td></td>
		</tr>
		<tr>
			<td>Competent Cells</td>
			<td>TakaRa</td>
			<td>636763</td>
			<td></td>
		</tr>
		<tr>
			<td>CutSmart&#160;</td>
			<td>NEB</td>
			<td>B7204S</td>
			<td></td>
		</tr>
		<tr>
			<td>CytoTune-iPS 2.0 Sendai Reprogramming Kit</td>
			<td>Thermo</td>
			<td>A16517</td>
			<td></td>
		</tr>
		<tr>
			<td>DirectPCR Lysis Reagent (cell)</td>
			<td>VIAGEN BIOTECH</td>
			<td>302-C</td>
			<td></td>
		</tr>
		<tr>
			<td>Dispase (1 U/mL)</td>
			<td>STEMCELL Technologies</td>
			<td>7923</td>
			<td></td>
		</tr>
		<tr>
			<td>Doxycycline Hydrochloride</td>
			<td>Fisher BioReagents</td>
			<td>BP26535</td>
			<td></td>
		</tr>
		<tr>
			<td>EcoRI-HF</td>
			<td>NEB</td>
			<td>R3101L</td>
			<td></td>
		</tr>
		<tr>
			<td>Fibronectin bovine plasma</td>
			<td>SIGMA</td>
			<td>F1141</td>
			<td></td>
		</tr>
		<tr>
			<td>&#160; 
			QIAEX II Gel Extraction Kit (500)</td>
			<td>QIAGEN</td>
			<td>20051</td>
			<td></td>
		</tr>
		<tr>
			<td>Gelatin from porcine skin, type A</td>
			<td>SIGMA</td>
			<td>G1890</td>
			<td></td>
		</tr>
		<tr>
			<td>HardSet Antifade Mounting Medium with DAPI</td>
			<td>Vector</td>
			<td>H-1500</td>
			<td></td>
		</tr>
		<tr>
			<td>Hygromycin B (50 mg/mL)</td>
			<td>Invitrogen</td>
			<td>10687010</td>
			<td></td>
		</tr>
		<tr>
			<td>Ketamine HCL Injection</td>
			<td>HENRY SCHEIN ANIMAL HEALTH</td>
			<td>45822</td>
			<td></td>
		</tr>
		<tr>
			<td>KpnI-HF</td>
			<td>NEB</td>
			<td>R3142L</td>
			<td></td>
		</tr>
		<tr>
			<td>lenti-CRISPRv2-blast</td>
			<td>Addgene</td>
			<td>83480</td>
			<td></td>
		</tr>
		<tr>
			<td>lenti-Guide-Hygro-iRFP670</td>
			<td>Addgene</td>
			<td>99377</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipofectamin 3000 Transfection Kit</td>
			<td>Invitrogen</td>
			<td>L3000015</td>
			<td></td>
		</tr>
		<tr>
			<td>LV-TRE-VP64-mouse MyoD-T2A-dsRedExpress2&#160;&#160;</td>
			<td>Addgene</td>
			<td>60625</td>
			<td></td>
		</tr>
		<tr>
			<td>LV-TRE-VP16 mouse MyoD-T2A-dsRedExpress2</td>
			<td>Addgene</td>
			<td>60626</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse on Mouse (M.O.M.) Basic Kit</td>
			<td>Vector</td>
			<td>BMK-2202</td>
			<td></td>
		</tr>
		<tr>
			<td>NotI-HF</td>
			<td>NEB</td>
			<td>R3189L</td>
			<td></td>
		</tr>
		<tr>
			<td>Opti-MEM I Reduced Serum Media</td>
			<td>ThermoFisher</td>
			<td>31985070</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyethylene glycol 4,000</td>
			<td>Alfa Aesar</td>
			<td>AAA161510B</td>
			<td></td>
		</tr>
		<tr>
			<td>Polybrene</td>
			<td>SIGMA</td>
			<td>TR1003</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning&#160;BioCoat Poly-D-Lysine/Laminin Culture Slide</td>
			<td>CORNING</td>
			<td>CB354688</td>
			<td></td>
		</tr>
		<tr>
			<td>PowerUp SYBR Green Master Mix</td>
			<td>ThermoFisher</td>
			<td>A25742</td>
			<td></td>
		</tr>
		<tr>
			<td>PrimeSTAR Max Premix</td>
			<td>TakaRa</td>
			<td>R045</td>
			<td></td>
		</tr>
		<tr>
			<td>Proteinase K</td>
			<td>VIAGEN BIOTECH</td>
			<td>507-PKP</td>
			<td></td>
		</tr>
		<tr>
			<td>Puromycin Dihydrochloride</td>
			<td>MP Biomedicals</td>
			<td>ICN19453980</td>
			<td></td>
		</tr>
		<tr>
			<td>qPCR Lentivirus Titration Kit</td>
			<td>abm</td>
			<td>LV900</td>
			<td></td>
		</tr>
		<tr>
			<td>Quick ligation kit</td>
			<td>NEB</td>
			<td>M2200S</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAprep Spin Miniprep Kit (250)</td>
			<td>QIAGEN</td>
			<td>27106</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAGEN Plasmid Plus Midi Kit (100)</td>
			<td>QIAGEN</td>
			<td>12945</td>
			<td></td>
		</tr>
		<tr>
			<td>RevertAid RT Reverse Transcription Kit</td>
			<td>Thermo scientific</td>
			<td>K1691</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAzol RT</td>
			<td>Molecular Research Center, INC</td>
			<td>RN 190</td>
			<td></td>
		</tr>
		<tr>
			<td>T4 DNA Ligase Reaction Buffer</td>
			<td>NEB</td>
			<td>B0202S</td>
			<td></td>
		</tr>
		<tr>
			<td>T4 Polynucleotide Kinase</td>
			<td>NEB</td>
			<td>M0201S</td>
			<td></td>
		</tr>
		<tr>
			<td>Terrific Broth Modified</td>
			<td>Fisher BioReagents</td>
			<td>BP9729-600</td>
			<td></td>
		</tr>
		<tr>
			<td>ViralBoost Reagent (500x)</td>
			<td>ALSTEM</td>
			<td>VB100</td>
			<td></td>
		</tr>
	</tbody>
</table>

crispr/cas9 technology in restoring dystrophin expression in ipsc-derived muscle progenitors

Duchenne muscular dystrophy (DMD) is a severe progressive muscle disease caused by mutations in the dystrophin gene, which ultimately leads to the exhaustion of muscle progenitor cells. Clustered regularly interspaced short palindromic repeats/CRISPR-associated 9 (CRISPR/Cas9) gene editing has the potential to restore the expression of the dystrophin gene. Autologous induced pluripotent stem cells (iPSCs)-derived muscle progenitor cells (MPC) can replenish the stem/progenitor cell pool, repair damage, and prevent further complications in DMD without causing an immune response. In this study, we introduce a combination of CRISPR/Cas9 and non-integrated iPSC technologies to obtain muscle progenitors with recovered dystrophin protein expression. Briefly, we use a non-integrating Sendai vector to establish an iPSC line from dermal fibroblasts of Dmdmdx mice. We then use the CRISPR/Cas9 deletion strategy to restore dystrophin expression through a non-homologous end joining of the reframed dystrophin gene. After PCR validation of exon23 depletion in three colonies from 94 picked iPSC colonies, we differentiate iPSC into MPC by doxycycline (Dox)-induced expression of MyoD, a key transcription factor playing a significant role in regulating muscle differentiation. Our results show the feasibility of using CRISPR/Cas9 deletion strategy to restore dystrophin expression in iPSC-derived MPC, which has significant potential for developing future therapies for the treatment of DMD.

Establishment of Dmdmdx skin fibroblasts derived iPSC. We demonstrated the efficiency of generating mouse iPSCs from Dmdmdx mice derived skin fibroblast using the integration-free reprogramming vectors. Figure 1A demonstrated that the appearance of embryonic stem cell (ESC)-like colonies at three weeks after infection. We evaluate the efficiency of iPSC induction by live alkaline phosphatase (AP) stain; Figure 1B s...

Watch this Scientific Journal Video about CRISPR/Cas9 Technology in Restoring Dystrophin Expression in iPSC-Derived Muscle Progenitors at JoVE.com

CRISPR/Cas9 Technology in Restoring Dystrophin Expression in iPSC-Derived Muscle Progenitors

Here, we present a Cas9-based exon23 deletion protocol to restore dystrophin expression in iPSC from Dmdmdx mouse-derived skin fibroblasts and directly differentiate iPSCs into myogenic progenitor cells (MPC) using the Tet-on MyoD activation system.

Duchenne muscular dystrophy (DMD) is a severe progressive muscle disease caused by mutations in the dystrophin gene, which ultimately leads to the ...

Duchenne is a muscular dystrophy causing premature exhausting of muscle progenitor cells. It is one of the most severe Muscular Dystrophies. To promote a functional muscle regeneration, we use CRISPR/Cas9-mediated gene editing to restore dystrophin expression in Induced Pluripotent Stem Cell-derived muscle progenitor cells.The CRISPR-Cas9 gene editing has the potential to restore dystrophin gene expression. Autologous iPSC-derived muscle progenitor cells can replenish the stem cell pore, repair damage, and prevent further complications in DMD without causing an immune response. Different agents of iPS cells into Myogenic Progenitor Cells reduced the risk of tumor re-genesis in iPS cells.Several therapies that combine autologous Induced Pluripotent Stem Cell-derived muscle progenitor cells with CRISPR-Cas9-mediated genetic correction are promising Duchenne Muscular Dystrophy treatment strategies. This technology can be used to treat many congenital diseases by genetically editing autologous stem cells, including heart, brain, and blood disease. We showed demonstration of this approach can provide the readers with experience in handling cell reprogramming and gene editing, which remains a challenge.Under an inverted microscope, examine the colonies of infected mouse embryonic stem cells. Mark the colonies at the bottom of the dish with the self-inking object marker. Apply greased cloning rings to cover the marked cell colonies.Add 100 microliters of 0.05%Trypsin-EDTA to each cloning ring and place the plate in an incubator at 37 degrees Celsius for five minutes. Then, transfer the digested cells with 100-microliter pipette tips to 48-well culture plates containing 250 milliliters of MES growth medium. Incubate the cells in the 37 Degree Celsius incubator with 5%Carbon Dioxide and 85%humidity.When they read 70%confluence, select the wells with well-grown cells and add 250 milliliters of TVP solution to digest for 30 minutes. Then, transfer the cell culture from each well to a six-centimeter dish. Repeat applying cloning rings and incubation for several times until uniform, dorm-shaped clones are obtained.Now, digest the prepared mouse iPSCs by adding one milliliter of TVP solution. Transfer the cell culture into a 24-well plate coated with Fibronectin and Gelatin and incubate at 37 degrees Celsius with 5%Carbon Dioxide. After the cells reach 50%confluence, switch to 500 microliters of fresh culture medium containing eight micrograms per milliliter Polybrene.Then, add 100 microliters of the lentiviral particle solution to the mouse iPSCs. Incubate the cells for three days at 37 degrees Celsius with 5%Carbon Dioxide. Next, determine the minimum concentration of Blasticidin and Hygromycin B which is at half kill rate within 24 hours.Add the media of 2.5 micrograms per milliliter Blasticidin and 100 micrograms per milliliter Hygromycin B into the cells, wait for three days, and select the cells that remain adherent as stabling infected cells. Digest the selected mouse iPSCs with 0.5 milliliters of TVP solution, each well in a new 24-well plate, and incubate cells for 30 minutes at 37 degrees Celsius with 5%Carbon Dioxide. Then, pipette the iPSCs into single cells and count the cells with a cell counting chamber.Select about 150 digested single cells and dilute with MES medium into 10 centimeter dish, culture at 37 degrees Celsius with 5%Carbon Dioxide. After about 10 days, under an inverted microscope, use 10 microliter sterile pipette tips to pick single colonies and transfer each colony into 50 microliters of TVP solution in a 96-well plate. Digest at 37 degrees Celsius for 30 minutes.Reliable manual cloning picking is critical for the success of harvesting CRISPR/Cas9-edited Induced Pluripotent Stem Cells. Then, transfer and divide the digested cells from each well into another two 96-well culture plates. Incubate at 37 degrees Celsius until 70%confluent.With the cell colonies at 70%confluence, remove the medium in the 96-well plate. Add 25 microliters of Lysis reagent containing 1%Proteinase K solution to each well and transfer the lysate to another 96-well PCR plate. Seal the PCR plate with adhesive seals and incubate the plate in a thermal cycler at 55 degrees Celsius for 30 minutes and then at 95 degrees Celsius for 45 minutes to lyse the cells and denature the Proteinase K.Then, in a PCR tube, add two microliters of the lysate, 10 microliters of 2x DNA Polymerase Premix, 7 microliters of DNase-free water, and one microliter of DMD Exon23 primers.Start the PCR reaction according to the manuscript. Then, load the PCR reaction supplied with 2.2 microliters of loading buffer onto a 2%agarose gel. Run the gel at 100 to 150 volts for 30 minutes and inspect the gel under UV light.In this protocol, two guide RNAs that flank the mutant Exon23 were designed. After Cas9-mediated double-stranded breaks and non-homologous end-joining, mutant Exon23 was deleted, allowing for truncated but functional Dystrophin production. To avoid the leakage of Trypsin solution, we need to apply grease evenly to the bottom of the rings.The combination of CRISPR/Cas9 genome editing with a tacked-on MyoD activation system provide a safe, feasible, and effective strategy for autologous transplantation in Duchenne Muscular Dystrophy patients with gene recovery basal progenitor cells.

crisprcas9-technology-restoring-dystrophin-expression-ipsc-derived

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JoVE Journal

Developmental Biology

8.2K visualizações.  Augusta University. Duchenne é uma distrofia muscular que causa exaustão prematura de células progenitoras musculares. É uma das distrofias musculares mais severas. Para promover uma regeneração muscular funcional, usamos a edição de genes mediados pelo CRISPR/Cas9 para restaurar a expressão da distrofina em células progenitoras musculares derivadas de células-tronco pluripotentes induzidas.A edição do gene CRISPR-Cas9 tem o potencial de restaurar a expressão genética da distrofina. Célula...