Name: isolation of human myoblasts, assessment of myogenic differentiation, and store-operated calcium entry measurement
Uploaded: 2017-07-26T12:30:00
Description: Watch this Scientific Journal Video about Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement at JoVE.com

This work was supported by the Swiss National Science Foundation (grant number 310030-166313), The "Fondation Suisse pour la recherche sur les maladies musculaires," the "Foundation Marcel Levaillant," and the "Fondation pour la recherche ost&#233;o-articulaire."

Human muscle samples (tissues obtained from semitendinous muscles) were collected during orthopedic surgery on healthy patients as surgical waste. All methods relating to the human study were performed in accordance with the guidelines and regulations of the Swiss Regulatory Health Authorities and approved by the Commission Cantonale d&#39;Ethique de la Recherche from the Geneva Cantonal Authorities, Switzerland (protocol CER n&#176; 12-259). Informed and written consents were obtained from all adult subjects involved in...

<ol>
	<li>Dumont, N. A., Bentzinger, C. F., Sincennes, M. C., Rudnicki, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Satellite+Cells+and+Skeletal+Muscle+Regeneration.">Satellite Cells and Skeletal Muscle Regeneration.</a> Compr Physiol. 5 (3), 1027-1059 (2015).</li><li>Sambasivan, R., Tajbakhsh, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adult+skeletal+muscle+stem+cells.">Adult skeletal muscle stem cells.</a> Results Probl Cell Differ. 56, 191-213 (2015).</li><li>Chen, W. 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=Isolation+of+blood-vessel-derived+multipotent+precursors+from+human+skeletal+muscle.">Isolation of blood-vessel-derived multipotent precursors from human skeletal muscle.</a> J Vis Exp. (90), e51195 (2014).</li><li>Zheng, 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=Isolation+of+myogenic+stem+cells+from+cultures+of+cryopreserved+human+skeletal+muscle.">Isolation of myogenic stem cells from cultures of cryopreserved human skeletal muscle.</a> Cell Transplant. 21 (6), 1087-1093 (2012).</li><li>Charville, G. W., 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=Ex+Vivo+Expansion+and+In+Vivo+Self-Renewal+of+Human+Muscle+Stem+Cells.">Ex Vivo Expansion and In Vivo Self-Renewal of Human Muscle Stem Cells.</a> Stem Cell Reports. 5 (4), 621-632 (2015).</li><li>Stiber, 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=STIM1+signalling+controls+store-operated+calcium+entry+required+for+development+and+contractile+function+in+skeletal+muscle.">STIM1 signalling controls store-operated calcium entry required for development and contractile function in skeletal muscle.</a> Nat Cell Biol. 10 (6), 688-697 (2008).</li><li>Prakriya, M., Lewis, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Store-Operated+Calcium+Channels.">Store-Operated Calcium Channels.</a> Physiol Rev. 95 (4), 1383-1436 (2015).</li><li>Darbellay, 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=STIM1-+and+Orai1-dependent+store-operated+calcium+entry+regulates+human+myoblast+differentiation.">STIM1- and Orai1-dependent store-operated calcium entry regulates human myoblast differentiation.</a> J Biol Chem. 284 (8), 5370-5380 (2009).</li><li>Darbellay, 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=Human+muscle+economy+myoblast+differentiation+and+excitation-contraction+coupling+use+the+same+molecular+partners,+STIM1+and+STIM2.">Human muscle economy myoblast differentiation and excitation-contraction coupling use the same molecular partners, STIM1 and STIM2.</a> J Biol Chem. 285 (29), 22437-22447 (2010).</li><li>Nilius, B., Owsianik, G., Voets, T., Peters, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transient+receptor+potential+cation+channels+in+disease.">Transient receptor potential cation channels in disease.</a> Physiol Rev. 87 (1), 165-217 (2007).</li><li>Vandebrouck, C., Martin, D., Colson-Van Schoor, M., Debaix, H., Gailly, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Involvement+of+TRPC+in+the+abnormal+calcium+influx+observed+in+dystrophic+(mdx)+mouse+skeletal+muscle+fibers.">Involvement of TRPC in the abnormal calcium influx observed in dystrophic (mdx) mouse skeletal muscle fibers.</a> J Cell Bio. 158 (6), 1089-1096 (2002).</li><li>Antigny, F., Koenig, S., Bernheim, L., Frieden, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=During+post-natal+human+myogenesis,+normal+myotube+size+requires+TRPC1-+and+TRPC4-mediated+Ca(2)(+)+entry.">During post-natal human myogenesis, normal myotube size requires TRPC1- and TRPC4-mediated Ca(2)(+) entry.</a> J Cell Sci. 126 (11), 2525-2533 (2013).</li><li>Brinkmeier, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TRP+channels+in+skeletal+muscle:+gene+expression,+function+and+implications+for+disease.">TRP channels in skeletal muscle: gene expression, function and implications for disease.</a> Adv Exp Med Biol. 704, 749-758 (2011).</li><li>Pan, Z., Brotto, M., Ma, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Store-operated+Ca2++entry+in+muscle+physiology+and+diseases.">Store-operated Ca2+ entry in muscle physiology and diseases.</a> BMB Rep. 47 (2), 69-79 (2014).</li><li>Lacruz, R. S., Feske, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diseases+caused+by+mutations+in+ORAI1+and+STIM1.">Diseases caused by mutations in ORAI1 and STIM1.</a> Ann N Y Acad Sci. 1356, 45-79 (2015).</li><li>Li, 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=STIM1-Ca(2+)+signaling+is+required+for+the+hypertrophic+growth+of+skeletal+muscle+in+mice.">STIM1-Ca(2+) signaling is required for the hypertrophic growth of skeletal muscle in mice.</a> Mol Cell Biol. 32 (15), 3009-3017 (2012).</li><li>Wei-Lapierre, L., Carrell, E. M., Boncompagni, S., Protasi, F., Dirksen, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orai1-dependent+calcium+entry+promotes+skeletal+muscle+growth+and+limits+fatigue.">Orai1-dependent calcium entry promotes skeletal muscle growth and limits fatigue.</a> Nat Commun. 4, 2805 (2013).</li><li>Konig, 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=Membrane+hyperpolarization+triggers+myogenin+and+myocyte+enhancer+factor-2+expression+during+human+myoblast+differentiation.">Membrane hyperpolarization triggers myogenin and myocyte enhancer factor-2 expression during human myoblast differentiation.</a> J Biol Chem. 279 (27), 28187-28196 (2004).</li><li>Crisan, 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=A+perivascular+origin+for+mesenchymal+stem+cells+in+multiple+human+organs.">A perivascular origin for mesenchymal stem cells in multiple human organs.</a> Cell Stem Cell. 3 (3), 301-313 (2008).</li><li>Bigot, 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=Age-Associated+Methylation+Suppresses+SPRY1,+Leading+to+a+Failure+of+Re-quiescence+and+Loss+of+the+Reserve+Stem+Cell+Pool+in+Elderly+Muscle.">Age-Associated Methylation Suppresses SPRY1, Leading to a Failure of Re-quiescence and Loss of the Reserve Stem Cell Pool in Elderly Muscle.</a> Cell Rep. 13 (6), 1172-1182 (2015).</li><li>Bettadapur, 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=Prolonged+Culture+of+Aligned+Skeletal+Myotubes+on+Micromolded+Gelatin+Hydrogels.">Prolonged Culture of Aligned Skeletal Myotubes on Micromolded Gelatin Hydrogels.</a> Sci Rep. 6, 28855 (2016).</li><li>Darbellay, B., Arnaudeau, S., Bader, C. R., Konig, S., Bernheim, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=STIM1L+is+a+new+actin-binding+splice+variant+involved+in+fast+repetitive+Ca2++release.">STIM1L is a new actin-binding splice variant involved in fast repetitive Ca2+ release.</a> J Cell Biol. 194 (2), 335-346 (2011).</li><li>Sauc, 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=STIM1L+traps+and+gates+Orai1+channels+without+remodeling+the+cortical+ER.">STIM1L traps and gates Orai1 channels without remodeling the cortical ER.</a> J Cell Sci. 128 (8), 1568-1579 (2015).</li><li>Demaurex, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium+measurements+in+organelles+with+Ca2+-sensitive+fluorescent+proteins.">Calcium measurements in organelles with Ca2+-sensitive fluorescent proteins.</a> Cell Calcium. 38 (3-4), 213-222 (2005).</li></ol>

The isolation and culture of human myoblasts from adult skeletal muscle offers an in vitro model to study muscle differentiation and muscle regeneration. In this paper, we provide a protocol that allows for the purification of high yields of human myoblasts in a simple and cost-limited way. In addition, this technique provides reliable and reproducible results in terms of percentage of myoblasts isolated and their myogenic differentiation efficiency. Indeed, we obtained around 60...

Human skeletal muscles are composed of groups of contractile, multinucleated muscle fibers resulting from the fusion of myogenic precursor cells. Skeletal muscles have the capacity to regenerate after injury thanks to the presence of SCs, the skeletal muscle stem cells located between the plasma membrane of myofibers (sarcolemma) and the basal lamina. In uninjured muscle, SCs are mostly present in a quiescent state. In response to mechanical stress or injury, SCs become activated (myoblasts), proliferate, and undergo either differentiation to form new myofibers or self-renewal to replenish the SC pool1,2. Over the years, several techniques were developed to isolate SCs and their progeny, the myoblasts, from skeletal muscle biopsies. With the greater understanding of the cell surface markers expressed on these cells and the methodology of fluorescence-activated cell sorting (FACS)3,4,5, it is now possible to isolate pure populations of human myoblasts from muscle samples.
Calcium signaling regulates skeletal muscle development, homeostasis, and regeneration. In particular, the Ca2+ entry that is activated following intracellular store depletion, called SOCE, is of great importance6 for these processes. Upon cell stimulation, the Ca2+ level in the endo/sarcoplasmic reticulum (ER/SR) decreases, which in turn activates plasma membrane Ca2+ channels that permit Ca2+ entry to refill the ER/SR7. The two main proteins involved in SOCE are the ER/SR Ca2+-sensing stromal interaction molecule 1 (STIM1) protein and the plasma membrane Ca2+ channel Orai1. Skeletal muscle abundantly expresses these two proteins, as well as other proteins of the same families (STIM2 and Orai2-Orai3)8,9 and several Ca2+-permeable channels of the transient receptor potential canonical (TRPC) family10,11,12,13. Ca2+ entry through the SOCE pathway is of great importance for muscle formation/regeneration14. Mutations of STIM1 or Orai1 proteins have deleterious effects on muscle function, leading mainly to muscle hypotonia15. Animal models with SOCE impairment also display reduced muscle mass and force, together with enhanced fatigability6,16,17. As mentioned, other STIM and Orai proteins, as well as many TRPC channels, are expressed in skeletal muscle, and their respective roles have not been determined so far. By knocking down their expression level, it is thus possible to investigate their implications in SOCE and their roles during human skeletal muscle differentiation.
SOCE measurement can be performed using two different approaches: electrophysiological current recordings and Ca2+ measurements. Electrophysiology is certainly a more direct method, as it measures the current of interest and its associated electrophysiological signature. However, this technique is very difficult to apply to muscle cells, mainly because of the large size of the muscle cells and the small size of the endogenous SOCE current. Cytosolic Ca2+ imaging is technically very accessible, but the measure is more indirect, as the Ca2+ level measured in the cytosol reflects both the entry of Ca2+ and the re-pumping out of the cell or in the internal stores.
A methodology that includes isolating myoblasts from small pieces of human skeletal muscle after enzymatic digestion, amplification, and FACS is explained in this paper. The process of muscle differentiation and the immunofluorescence protocol to follow the expression of differentiation markers over time are described18. Finally, the measurement of SOCE and the role of different ion channels in Ca2+ signaling and skeletal muscle differentiation are explained.

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			<td height="25" style="height:25px;width:321px;">Ham&#8217;s F10</td>
			<td style="width:235px;">ThermoFisher Scientific</td>
			<td style="width:187px;">31550-023</td>
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			<td height="25" style="height:25px;width:321px;">Gentamycin</td>
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			<td height="25" style="height:25px;width:321px;">Trypsin-EDTA 0.05%</td>
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			<td height="25" style="height:25px;width:321px;">70 &#956;m cell strainer</td>
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			<td style="width:235px;">Falcon</td>
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			<td height="25" style="height:25px;width:321px;">Falcon 5&#160;ml tube (FACS)</td>
			<td style="width:235px;">Falcon</td>
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			<td height="25" style="height:25px;width:321px;">Culture medium: OPTI-MEM</td>
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			<td height="25" style="height:25px;width:321px;">Mouse anti-MyHC *</td>
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			<td style="width:201px;"></td>
		</tr>
		<tr height="49">
			<td height="49" style="height:49px;width:321px;">DAPI</td>
			<td style="width:235px;">Sigma</td>
			<td style="width:187px;">D9542</td>
			<td style="width:201px;">CAUTION:&#160; toxic compound</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:321px;">Paraformaldehyde</td>
			<td style="width:235px;">Fluka</td>
			<td style="width:187px;">762400</td>
			<td style="width:201px;"></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:321px;">Fura-2 AM</td>
			<td style="width:235px;">ThermoFisher Scientific</td>
			<td style="width:187px;">F1201</td>
			<td style="width:201px;"></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:321px;">Pluronic F-127</td>
			<td style="width:235px;">ThermoFisher Scientific</td>
			<td style="width:187px;">P3000MP</td>
			<td style="width:201px;"></td>
		</tr>
		<tr height="49">
			<td height="49" style="height:49px;width:321px;">Thapsigargin</td>
			<td style="width:235px;">Sigma</td>
			<td style="width:187px;">T9033</td>
			<td style="width:201px;">CAUTION&#160;: toxic compound&#160;</td>
		</tr>
		<tr height="49">
			<td height="49" style="height:49px;width:321px;">Ratio imaging acquisition software: Metafluor 6.3</td>
			<td style="width:235px;">Molecular Device</td>
			<td style="width:187px;"></td>
			<td style="width:201px;"></td>
		</tr>
		<tr height="24">
			<td colspan="2" height="24" style="height:24px;">*&#160;: MF 20 was deposited to the DSHB by Fischman, D.A.&#160;</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

isolation of human myoblasts, assessment of myogenic differentiation, and store-operated calcium entry measurement

Satellite cells (SC) are muscle stem cells located between the plasma membrane of muscle fibers and the surrounding basal lamina. They are essential for muscle regeneration. Upon injury, which occurs frequently in skeletal muscles, SCs are activated. They proliferate as myoblasts and differentiate to repair muscle lesions. Among many events that take place during muscle differentiation, cytosolic Ca2+ signals are of great importance. These Ca2+ signals arise from Ca2+ release from internal Ca2+ stores, as well as from Ca2+ entry from the extracellular space, particularly the store-operated Ca2+ entry (SOCE). This paper describes a methodology used to obtain a pure population of human myoblasts from muscle samples collected after orthopedic surgery. The tissue is mechanically and enzymatically digested, and the cells are amplified and then sorted by flow cytometry according to the presence of specific membrane markers. Once obtained, human myoblasts are expanded and committed to differentiate by removing growth factors from the culture medium. The expression levels of specific transcription factors and in vitro immunofluorescence are used to assess the myogenic differentiation process in control conditions and after silencing proteins involved in Ca2+ signaling. Finally, we detail the use of Fura-2 as a ratiometric Ca2+ probe that provides reliable and reproducible measurements of SOCE.

After the enzymatic dissociation of a human muscle sample, cells were amplified in GM. Human myoblasts, defined as CD56+/CD146+/CD45-/CD34-/CD144- cells, were obtained after FACS. Myoblasts represented more than 60% of the analyzed population (Figure 1). Primary human myoblasts were replated, grown to confluence, and cultured in DM for 48 h. After immunostaining for the expression of the transcription factor MEF2 and the muscle-specific protein myosin heavy chain (MyHC), we observed that a m...

Watch this Scientific Journal Video about Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement at JoVE.com

Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement

Here, we describe a methodology to obtain a pure population of human myoblasts from adult muscle tissue. These cells are used to study in vitro skeletal muscle differentiation and, in particular, to study proteins involved in Ca2+ signaling.

Satellite cells (SC) are muscle stem cells located between the plasma membrane of muscle fibers and the surrounding basal lamina. They are essential for ...

The overall goal of this procedure is to obtain a pure population of human myoblasts from adult skeletal muscle. These cells are used for functional studies such as assessment of myogenic differentiation and measurement of store-operated calcium entry. The main advantage of this technique is that it allows a rapid, simple and reproducible isolation of human primary myoblasts.These myoblasts are the new ex-vivo to study the calcium signaling during muscle regeneration. This method can help answer key questions in the muscle field such as, identifying the ionic channels and the transcription factors involved during muscle differentiation. For this method can provide insight into gene functions during human myogenic differentiation.It can also be applied to other studies such as, potential for using myogenic stem cells to treat muscular dystrophies. Transfer the muscle sample into a sterile six centimeter plate, wash the sample with PBS twice. Remove any remaining adipose tissue and weigh the sample.Next, add trypsin and mince the muscle into pieces smaller than two millimeters in size. Once minced, use a 10 milliliter pipette to transfer the tissue into a 200 milliliter dissociation bottle containing a stir bar, then continue collecting minced tissue in trypsin solution until the dissociation bottle is filled to 90 milliliters. Now, incubate the tissue in a water bath at 37 degrees celsius for 60 minutes with gentle stirring.After an hour, add 10 milliliters of FCS to stop the reaction and homogenize the mixture using trituration. Now, load 70 micron strainers onto two 50 milliliter tubes and pass half of the cell suspension through each strainer by pipetting the suspension into the filters. Next, make a suspension of the cells in growth medium and plate 200, 000 cells onto six centimeter plates with four milliliters of medium.Incubate the plates, changing the medium every third day. After five to seven days, the cells should be 70%to 80%confluent, then, stain them. To begin, rinse the plate of confluent cells with PBS.Then, add one milliliter of trypsin solution and let the enzyme work for three minutes. Stop the reaction by adding two milliliters of medium and collect the cells in a 15 milliliter tube. Then, spin the cells down and re-suspend them in one milliliter of medium.Next, take a cell count while storing the cells on ice. For the facts analysis, load seven tubes with 100, 000 cells each. Load the remaining cells into an eighth tube for sorting.Wash the cells with one milliliter of cold fax buffer, then, centrifuge the tubes and aspirate and discard the supernatant. Add back 200 microliters of fax buffer with the appropriate antibodies and let the cells incubate on ice for 30 minutes. After 30 minutes, wash the cells again and re-suspend them in 500 microliters of fax buffer, then sort the cells using a flow cytometer.After excluding the CD45 positive hematopoietic cells, separate the CD45 negative cells based on CD56 expression. Then, gate the CD56 positive population for CD34, CD144 and CD146. Re-analyse a fraction of the sorted population, to check the purity.Now, pull the human myoblasts and wash them with five milliliters of medium. Then re-suspend them in one milliliter of medium. Transfer the suspension to a six centimeter plate with four milliliters of medium and incubate the plate at 37 degrees celsius with 7%carbon dioxide.For this procedure, have cultured myoblasts and make fresh transvection medium. Incubate the medium at room temperature for 15 to 20 minutes. During the medium incubation, prepare the myoblasts.First, rinse them once with PBS. Then, trypsinise the adherent cells. Stop the reaction by adding two milliliters of medium.Then, collection the cells into a 50 milliliter tube. Spin them down and re-suspend them in one milliliter of medium. For each transvection, prepare 500, 000 cells in 200 microliters of medium.To each 500 microliters of transvection medium, add a 200 microliter aliquot of cells and then mix using only two strokes of the pipette gun. Then, let the reactions proceed for five minutes at room temperature. After five minutes, transfer the reactions to 3.5 centimeter culture dishes, each containing one glass cover slip.Next, add 1.3 milliliters of medium for a final volume of two milliliters and incubate the dishes. After 48 hours of differentiation, the cells can be immunostained or analyzed using calcium imaging. For either option, first carefully wash the cells twice using one milliliter of room temperature PBS to wash.Try to avoid detaching the myotubes. For a calcium imaging, cover the washed cells with two micromolar fura-2 AM plus one micromolar threonic acid in calcium containing medium. Then, let them incubate for about 30 minutes before mixing.Next, wash the cells twice with unmodified calcium containing medium and then, incubate them for 10 to 15 minutes for the esterification. Now, remove the cover slip from a culture plate and install it into the experimental chamber. Load the chamber with calcium containing medium, place it under a microscope, then, start the data recording.Fura-2 is excited alternately at 340 and 380 nanometers. The emission light is collected at 510 nanometers. Diving the 340 nanometer nanometer images by the 380 images, provides the image ratios as the fluctuations and calcium concentration are relatively low, acquire one image ratio every two seconds.After two or three minutes, replace the medium with calcium free medium. Then, for one or two minutes, monitor the activity of the store operated calcium in the cells. Next, add one micromolar thapsigargin to the cells to deplete their internal calcium stores.Wait eight to 10 minutes, then, rapidly replace the medium with the calcium containing medium and record for five minutes while calcium enters the cells via the suc e channels. After terminating the experiment, analyze the images. Select an area where there are no cells for region one, which defines the background, then, select an area in the cytoplasm for region two.The two regions can be drawn on any of the images in the series. Next, go to the run experiments tab and select reference images for the 340 and 380 channels, select region one, then click on subtract background. Now, run the entire experiment to remove the background from all the images.Once completed, click log data option to open a spreadsheet in which the time and the ratio data are logged. Muscle cells were grown up, expanded and sorted using fax. Myoblasts represented more than 60%of the analyzed population.The primary human myoblasts were then cultured in differentiation medium and immunostained for the transcription factor of MEF2 and myosin heavy chain proteins. A majority of cells expressed myosin heavy chain and formed myotubes with fusion index values of about 60%the other 40%of the cells remained undifferentiated mononucleated cells, also known as reserve cells. The described store operated calcium entry experiment were successfully performed on the differentiated cells.Performing the same experiment to on cells transvected with small interfering RNA, directed against calcium permeable channels of the TRPC family, shows that the knockdown had a measurable impact on store operated calcium entry. After watching this video, you should have a good understanding of how to isolate human myoblasts from adult skeletal muscle. We use these cells to study the successive steps of muscle differentiation and in particular, deactivation of the transcription factors and calcium channels.Once mastered, this technique can be done in less than three hours if it is performed properly. It is a rapid, simple, reproducible method that obtains the yield of human myoblasts. While attempting this procedure, it is important to prevent the myoblast cultures from reaching full confidence, as there will be unwanted spontaneous differentiation.

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Research

JoVE Journal

Developmental Biology

Isolation and Quantitative Immunocytochemical Characterization of Primary Myogenic Cells and Fibroblasts from Human Skeletal Muscle

The repair and regeneration of skeletal muscle requires the action of satellite cells, which are the resident muscle stem cells. These can be isolated from human muscle biopsy samples using enzymatic digestion and their myogenic properties studied in culture. Quantitatively, the two main adherent cell types obtained from enzymatic digestion are: (i) the satellite cells (termed myogenic cells or muscle precursor cells), identified initially as CD56+ and later as CD56+/desmin+ cells and (ii) muscle-derived fibroblasts, identified as CD56&#8211; and TE-7+. Fibroblasts proliferate very efficiently in culture and in mixed cell populations these cells may overrun myogenic cells to dominate the culture. The isolation and purification of different cell types from human muscle is thus an important methodological consideration when trying to investigate the innate behavior of either cell type in culture. Here we describe a system of sorting based on the gentle enzymatic digestion of cells using collagenase and dispase followed by magnetic activated cell sorting (MACS) which gives both a high purity (&#62;95% myogenic cells) and good yield (~2.8 x 106 &#177; 8.87 x 105 cells/g tissue after 7 days in vitro) for experiments in culture. This approach is based on incubating the mixed muscle-derived cell population with magnetic microbeads beads conjugated to an antibody against CD56 and then passing cells though a magnetic field. CD56+ cells bound to microbeads are retained by the field whereas CD56&#8211; cells pass unimpeded through the column. Cell suspensions from any stage of the sorting process can be plated and cultured. Following a given intervention, cell morphology, and the expression and localization of proteins including nuclear transcription factors can be quantified using immunofluorescent labeling with specific antibodies and an image processing and analysis package.

The main adherent cell types derived from human muscle are myogenic cells and fibroblasts. Here, cell populations are enriched using magnetic-activated cell sorting based on the CD56 antigen. Subsequent immunolabelling with specific antibodies and use of image analysis techniques allows quantification of cytoplasmic and nuclear characteristics in individual cells.

The repair and regeneration of skeletal muscle requires the action of satellite cells, which are the resident muscle stem cells. These can be isolated ...

Analysis of Zebrafish Larvae Skeletal Muscle Integrity with Evans Blue Dye

The zebrafish model is an emerging system for the study of neuromuscular disorders. In the study of neuromuscular diseases, the integrity of the muscle membrane is a critical disease determinant. To date, numerous neuromuscular conditions display degenerating muscle fibers with abnormal membrane integrity; this is most commonly observed in muscular dystrophies. Evans Blue Dye (EBD) is a vital, cell permeable dye that is rapidly taken into degenerating, damaged, or apoptotic cells; in contrast, it is not taken up by cells with an intact membrane. EBD injection is commonly employed to ascertain muscle integrity in mouse models of neuromuscular diseases. However, such EBD experiments require muscle dissection and/or sectioning prior to analysis. In contrast, EBD uptake in zebrafish is visualized in live, intact preparations. Here, we demonstrate a simple and straightforward methodology for performing EBD injections and analysis in live zebrafish. In addition, we demonstrate a co-injection strategy to increase efficacy of EBD analysis. Overall, this video article provides an outline to perform EBD injection and characterization in zebrafish models of neuromuscular disease.

In this study, we describe a straightforward method to perform Evans Blue Dye (EBD) analysis on zebrafish larvae. This technique is a powerful tool for the characterization of skeletal muscle integrity and delineation of zebrafish models of muscular dystrophy, and is a valuable method for the development of novel therapeutics.

The zebrafish model is an emerging system for the study of neuromuscular disorders.  In the study of neuromuscular diseases, the integrity of the muscle ...

Differentiation of the SH-SY5Y Human Neuroblastoma Cell Line

Having appropriate in vivo and in vitro systems that provide translational models for human disease is an integral aspect of research in neurobiology and the neurosciences. Traditional in vitro experimental models used in neurobiology include primary neuronal cultures from rats and mice, neuroblastoma cell lines including rat B35 and mouse Neuro-2A cells, rat PC12 cells, and short-term slice cultures. While many researchers rely on these models, they lack a human component and observed experimental effects could be exclusive to the respective species and may not occur identically in humans. Additionally, although these cells are neurons, they may have unstable karyotypes, making their use problematic for studies of gene expression and reproducible studies of cell signaling. It is therefore important to develop more consistent models of human neurological disease. 
The following procedure describes an easy-to-follow, reproducible method to obtain homogenous and viable human neuronal cultures, by differentiating the chromosomally stable human neuroblastoma cell line, SH-SY5Y. This method integrates several previously described methods1-4 and is based on sequential removal of serum from media. The timeline includes gradual serum-starvation, with introduction of extracellular matrix proteins and neurotrophic factors. This allows neurons to differentiate, while epithelial cells are selected against, resulting in a homogeneous neuronal culture. Representative results demonstrate the successful differentiation of SH-SY5Y neuroblastoma cells from an initial epithelial-like cell phenotype into a more expansive and branched neuronal phenotype. This protocol offers a reliable way to generate homogeneous populations of neuronal cultures that can be used for subsequent biochemical and molecular analyses, which provides researchers with a more accurate translational model of human infection and disease.

It is critical in neurobiology and neurovirology to have a reliable, replicable in vitro system that serves as a translational model for what occurs in vivo in human neurons. This protocol describes how to culture and differentiate SH-SY5Y human neuroblastoma cells into viable neurons for use in in vitro applications.

Having appropriate in vivo and in vitro systems that provide translational models for human disease is an integral aspect of research in neurobiology and ...

Isolation and Differentiation of Adipose-Derived Stem Cells from Porcine Subcutaneous Adipose Tissues

Obesity is an unconstrained worldwide epidemic. Unraveling molecular controls in adipose tissue development holds promise to treat obesity or diabetes. Although numerous immortalized adipogenic cell lines have been established, adipose-derived stem cells from the stromal vascular fraction of subcutaneous white adipose tissues provide a reliable cellular system ex vivo much closer to adipose development in vivo. Pig adipose-derived stem cells (pADSC) are isolated from 7- to 9-day old piglets. The dorsal white fat depot of porcine subcutaneous adipose tissues is sliced, minced and collagenase digested. These pADSC exhibit strong potential to differentiate into adipocytes. Moreover, the pADSC also possess multipotency, assessed by selective stem cell markers, to differentiate into various mesenchymal cell types including adipocytes, osteocytes, and chondrocytes. These pADSC can be used for clarification of molecular switches in regulating classical adipocyte differentiation or in direction to other mesenchymal cell types of mesodermal origin. Furthermore, extended lineages into cells of ectodermal and endodermal origin have recently been achieved. Therefore, pADSC derived in this protocol provide an abundant and assessable source of adult mesenchymal stem cells with full multipotency for studying adipose development and application to tissue engineering of regenerative medicine.

This protocol describes the isolation of pig adipose-derived stem cells (pADSC) from subcutaneous adipose tissues with examination of multipotency. The multipotent pADSC are used to delineate processes of adipocyte differentiation and study transdifferentiation into multiple cell lineages of mesodermal mesenchyme or further lineages of ectoderm and endoderm for regenerative studies.

Obesity is an unconstrained worldwide epidemic. Unraveling molecular controls in adipose tissue development holds promise to treat obesity or diabetes. ...

Preparation and Culture of Myogenic Precursor Cells/Primary Myoblasts from Skeletal Muscle of Adult and Aged Humans

Skeletal muscle homeostasis depends on muscle growth (hypertrophy), atrophy and regeneration. During ageing and in several diseases, muscle wasting occurs. Loss of muscle mass and function is associated with muscle fiber type atrophy, fiber type switching, defective muscle regeneration associated with dysfunction of satellite cells, muscle stem cells, and other pathophysiological processes. These changes are associated with changes in intracellular as well as local and systemic niches. In addition to most commonly used rodent models of muscle ageing, there is a need to study muscle homeostasis and wasting using human models, which due to ethical implications, consist predominantly of in vitro cultures. Despite the wide use of human Myogenic Progenitor Cells (MPCs) and primary myoblasts in myogenesis, there is limited data on using human primary myoblast and myotube cultures to study molecular mechanisms regulating different aspects of age-associated muscle wasting, aiding in the validation of mechanisms of ageing proposed in rodent muscle. The use of human MPCs, primary myoblasts and myotubes isolated from adult and aged people, provides a physiologically relevant model of molecular mechanisms of processes associated with muscle growth, atrophy and regeneration. Here we describe in detail a robust, inexpensive, reproducible and efficient protocol for the isolation and maintenance of human MPCs&#160;and their progeny&#160;&#8212; myoblasts and myotubes from human muscle samples using enzymatic digestion. Furthermore, we have determined the passage number at which primary myoblasts from adult and aged people undergo senescence in an in vitro culture. Finally, we show the ability to transfect these myoblasts and the ability to characterize their proliferative and differentiation capacity and propose their suitability for performing functional studies of molecular mechanisms of myogenesis and muscle wasting in vitro.

This protocol describes a robust, reproducible and simple method of isolation and culture of myoblast progenitor cells from the skeletal muscle of adult and aged people. The muscles used here include foot and leg muscles. This approach enables the isolation of an enriched population of primary myoblasts for functional studies.

Skeletal muscle homeostasis depends on muscle growth (hypertrophy), atrophy and regeneration. During ageing and in several diseases, muscle wasting ...

Directed Differentiation of Primitive and Definitive Hematopoietic Progenitors from Human Pluripotent Stem Cells

One of the major goals for regenerative medicine is the generation and maintenance of hematopoietic stem cells (HSCs) derived from human pluripotent stem cells (hPSCs). Until recently, efforts to differentiate hPSCs into HSCs have predominantly generated hematopoietic progenitors that lack HSC potential, and instead resemble yolk sac hematopoiesis.&#160;These resulting hematopoietic progenitors may have limited utility for in vitro disease modeling of various adult hematopoietic disorders, particularly those of the lymphoid lineages. However, we have recently described methods to generate erythro-myelo-lymphoid multilineage definitive hematopoietic progenitors from hPSCs using a stage-specific directed differentiation protocol, which we outline here. Through enzymatic dissociation of hPSCs on basement membrane matrix-coated plasticware, embryoid bodies (EBs) are formed. EBs are differentiated to mesoderm by recombinant BMP4, which is subsequently specified to the definitive hematopoietic program by the GSK3&#946; inhibitor, CHIR99021. Alternatively, primitive hematopoiesis is specified by the PORCN inhibitor, IWP2. Hematopoiesis is further driven through the addition of recombinant VEGF and supportive hematopoietic cytokines. The resulting hematopoietic progenitors generated using this method have the potential to be used for disease and developmental modeling, in vitro.

Here, we present human pluripotent stem cell (hPSC) culture protocols, used to differentiate hPSCs into CD34+ hematopoietic progenitors. This method uses stage-specific manipulation of canonical WNT signaling to specify cells exclusively to either the definitive or primitive hematopoietic program.

One of the major goals for regenerative medicine is the generation and maintenance of hematopoietic stem cells (HSCs) derived from human pluripotent stem ...

Isolation, Culture, and Differentiation of Bone Marrow Stromal Cells and Osteoclast Progenitors from Mice

Bone marrow stromal cells (BMSCs) constitute a cell population routinely used as a representation of mesenchymal stem cells in vitro. They reside within the bone marrow cavity alongside hematopoietic stem cells (HSCs), which can give rise to red blood cells, immune progenitors, and osteoclasts. Thus, extractions of cell populations from the bone marrow results in a very heterogeneous mix of various cell populations, which can present challenges in experimental design and confound data interpretation. Several isolation and culture techniques have been developed in laboratories in order to obtain more or less homogeneous populations of BMSCs and HSCs invitro. Here, we present two methods for isolation of BMSCs and HSCs from mouse long bones: one method that yields a mixed population of BMSCs and HSCs and one method that attempts to separate the two cell populations based on adherence. Both methods provide cells suitable for osteogenic and adipogenic differentiation experiments as well as functional assays.

In this article, we present methods to isolate and differentiate bone marrow stromal cells and hematopoietic stem cells from mouse long bones. Two different protocols are presented yielding different cell populations suitable for expansion and differentiation into osteoblasts, adipocytes, and osteoclasts.

Bone marrow stromal cells (BMSCs) constitute a cell population routinely used as a representation of mesenchymal stem cells in vitro. They reside within ...

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.

The liver detoxifies harmful substances, secretes vital proteins, and executes key metabolic activities, thus sustaining life. Consequently, liver ...

Isolation, Propagation, and Prion Protein Expression During Neuronal Differentiation of Human Dental Pulp Stem Cells

Bioethical issues related to the manipulation of embryonic stem cells have hindered advances in the field of medical research. For this reason, it is very important to obtain adult stem cells from different tissues such as adipose, umbilical cord, bone marrow and blood. Among the possible sources, dental pulp is particularly interesting because it is easy to obtain in respect of bioethical considerations. Indeed, human Dental Pulp Stem Cells (hDPSCs) are a type of adult stem cells able to differentiate in neuronal-like cells and can be obtained from the third molar of healthy patients (13-19 ages). In particular, the dental pulp was removed with an excavator, cut into small slices, treated with collagenase IV and cultured in a flask. To induce the neuronal differentiation, hDPSCs were stimulated with EGF/bFGF for 2 weeks. Previously, we have demonstrated that during the differentiation process the content of cellular prion Protein (PrPC) in hDPSCs increased. The cytofluorimetric analysis showed an early expression of PrPC that increased after neuronal differentiation process. Ablation of PrPC by siRNA PrP prevented neuronal differentiation induced by EGF/bFGF. In this paper, we illustrate that as we enhanced the isolation, separation and in vitro cultivation methods of hDPSCs with several easy procedures, more efficient cell clones were obtained and large-scale expansion of the mesenchymal stem cells (MSCs) was observed. We also show how the hDPSCs, obtained with methods detailed in the protocol, are an excellent experimental model to study the neuronal differentiation process of MSCs and subsequent cellular and molecular processes.

Here we present a protocol for human Dental Pulp Stem Cells isolation and propagation in order to evaluate the prion protein expression during neuronal differentiation process.

Bioethical issues related to the manipulation of embryonic stem cells have hindered advances in the field of medical research. For this reason, it is very ...

Isolation, Culture, Characterization, and Differentiation of Human Muscle Progenitor Cells from the Skeletal Muscle Biopsy Procedure

The use of primary human tissue and cells is ideal for the investigation of biological and physiological processes such as the skeletal muscle regenerative process. There are recognized challenges to working with human primary adult stem cells, particularly human muscle progenitor cells (hMPCs) derived from skeletal muscle biopsies, including low cell yield from collected tissue and a large degree of donor heterogeneity of growth and death parameters among cultures. While incorporating heterogeneity into experimental design requires a larger sample size to detect significant effects, it also allows us to identify mechanisms that underlie variability in hMPC&#160;expansion capacity, and thus allows us to better understand heterogeneity in skeletal muscle regeneration. Novel mechanisms that distinguish the expansion capacity of cultures have the potential to lead to the development of therapies to improve skeletal muscle regeneration.

We present techniques for isolating, culturing, characterizing, and differentiating human primary muscle progenitor cells (hMPCs) obtained from skeletal muscle biopsy tissue. hMPCs obtained and characterized through these methods can be used to subsequently address research questions related to human myogenesis and skeletal muscle regeneration.