The authors would like to extend many thanks to Drs. Josep Planas and Juan Castillo for their professional expertise in the development and application of this culture protocol to small fishes and amphibians. Thanks are also due to the countless individuals who have tirelessly assisted with the dissection and dissociation of muscle tissue from many fish (both in species and number), including Matthew Charging, Delci Christensen, Zachary Fowler, Brooke Franzen, Nathan Froehlich, Kira Marshall, Ben Meyer, Ethan Remily, and Sinibaldo Romero. This work was supported by University of Alabama at Birmingham Department of Biology start-up funds, Center for Protease Research NIH Grant # 2P20 RR015566, NIH NIAMS Grant # R03AR055350, and NDSU Advance FORWARD NSF Grant #HRD-0811239 to PRB. Support was also provided by the UAB Nutrition Obesity Research Center award # P30DK056336, NIH NIDDK. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH.

Ethics Statement: All experimentation involving vertebrate animals described herein was approved in advance by the Institutional Animal Care and Use Committee of the University of Alabama at Birmingham and is consistent with guidelines established by the Office of Laboratory Animal Welfare, National Institutes of Health of the U.S. Department of Health and Human Services.
1. Preparation for Culture
<ol>
	<li>Prepare the base medium as follows: 9 mM NaHCO3 (1.51 g per 2 L)...

The myogenic program, in whichever species examined, can be most easily studied through an in vitro system. Indeed, upon isolation, myogenic precursor cells (MPCs) in fish or myosatellite cells (MSCs) in mammals readily enter this highly regulated process involving the proliferation, cell cycle withdrawal, and terminal differentiation of myoblasts and the fusion of those myoblasts into nascent myotubes. The general lack of transgenic gene reporter strains of piscine species (with the possible exception of the ze...

Considerable understanding of mammalian myogenesis has been obtained through the recapitulation of this process in both primary mouse (Mus musculus) myoblast cultures and the well-described mouse-derived cell line, C2C125. Beginning in the 1950s6, these cultures have led to much advancement in the understanding of the murinemyogenic program and, by extension, myogenesis in other vertebrates. Additionally, single cell myofiber explant techniques have increased out understanding of interactions between satellite cells and surrounding myofibers7-9.Cell cultures are particularly attractive for investigations of myogenesis due to the short time from precursor to differentiated cell10, relative ease of transfection for RNAi11-14, transgenic15,16 and overexpression studies14,17,18 , in vitro expansion followed by in vivo transplantation18-20, and even comparison of myogenic precursor cells and their regulating agents across taxa21,22. While differences due to the artificial environment of the culture system have been described5,23 , these in vitro systems have proven to be indispensible to our dissection of the intricate program governing the formation of multinucleated, terminally differentiated myofibersfrom mononucleated proliferative progenitor cells known as myosatellite cells (MSCs) among the mammals.
Outside of the class Mammalia, however, the conservation and/or divergence of mechanisms controlling myogenesis are poorly understood, largely due to the difficulty in culturing myogenic precursor cells (MPCs) and myoblasts from various taxa. Indeed, primary myoblast cultures have only been described in three birds24-26, one reptile27, a few amphibians28-30, and some fishes1,3,4,31-33. Continuous myogenic cell lines from vertebrates other than rodents34-36are even more rare, with the only non-mammalian myogenic cell line being derived from Japanese quail (Cortunix japonica), QM737. Despite many attempts at immortalization, a teleost myogenic cell line remains elusive and a protocol for efficient transfection of these cells was only published this year15. Thus, clear and well-optimized protocols for culturing primary MPCs and myoblasts from a variety of vertebrates are very much needed to not only further expand our knowledge of the evolution of the myogenic program, but to employ the power of comparative physiology to make breakthroughs in the treatment of human skeletal muscle diseases and disorders.
While the literature contains many reports of MPC/myoblast isolation38-49, it is common for authors to describe the protocols for such isolations in brief, often incomplete, formats. Further, the most instructive protocols reported have been developed for mice50-53, and some of these rely on antibody selection54,55 or fluorescence transgenes56,57, making these protocols unusable or impractical inmost non-rodent species utilized by muscle biologists. With little known about piscine, amphibian, and reptile myogenesis, a detailed and thorough protocol, described with audiovisual guidance and with demonstrated efficiency in distantly related species, would be most helpful to the field.
First described by Powell and colleagues in 198958, the following protocol was initially developed to isolate MPCs and myoblasts from salmonid fishes (namely, rainbow trout, Oncorhynchus mykiss, and Atlantic salmon, Salmo salar) and some larger cyprinids (i.e.&#160;goldfish, Carassiusauratusauratus). In 2000, Fauconneau and Paboeuf optimized a primary myoblast culture for rainbow trout59, and minoroptimizations made that protocol utilizable in several smaller minnows of the Danioninae clade (zebrafish, Danio rerio, and giant danio, Devario aequipinnatus)32 due to the many genetic tools available for zebrafish work and thus its close relatives. Teleost fish are attractive organisms for study due to their divergent growth strategy (at least in most species). Large salmonids, like most fishes, grow indeterminately, with growth potential unfettered by an asymptote at maturity, even in old age60-62. Unlike zebrafish, large danionins such as the giant danio63 and moustached danio display growth potentials typical of teleost fish, making their direct juxtaposition an ideal platform for understanding whether MPC cell fate choice plays a role in skeletal muscle hyperplasia versus hypertrophy.
Likewise, we have demonstrated that this protocol can be used with mice and axolotls, with relatively high cell yield and viability indices. Urodele salamanders, such as the Mexican axolotl (Ambystomamexicanum),possess the remarkable ability to regenerate tissues, including entire limbs and tails64-66. This characteristic makes these amphibians interesting models of skeletal muscle wasting and aging. Using the protocol described below, a similar approach can be undertaken as has been done in many fish species, providing an even wider comparative context for such studies. As many truly comparative biologists appreciate, the most meaningful advances in basic biology and translational biomedicine can be made when data are analyzed within the widest spectrum (here, the entire vertebrate lineage).

<table border="0" cellpadding="0" cellspacing="0" width="743">
	<tbody>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 1. Detailed Reagent Information</td>
		</tr>
		<tr>
			<td height="42" style="height:43px;width:205px;">Reagent</td>
			<td style="width:217px;">Company (Preferred v. Alternate)</td>
			<td style="width:160px;">Catalog Number (Preferred v. Alternate)</td>
			<td style="width:161px;">Quantity per Culture</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;">&#947;-irradiated poly-L-lysine</td>
			<td>Sigma-Aldrich (MP Biomedicals)</td>
			<td>P5899 (ICN19454405)</td>
			<td>5 mg</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">DMEM (high glucose)</td>
			<td>Sigma-Aldrich (cellgro)</td>
			<td>MT-50-003-PB (D7777)</td>
			<td>2 L</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">Laminin</td>
			<td>BD Biosciences (Sigma-Aldrich)</td>
			<td>CB-40232 (L2020)</td>
			<td>1 mg</td>
		</tr>
		<tr>
			<td height="41" style="height:41px;width:205px;">Sodium Bicarbonate (NaHCO3)</td>
			<td>Fisher Scientific (Sigma-Aldrich)</td>
			<td>BP328-500 (S5761)</td>
			<td>1.51 g</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">HEPES (C8H18N2O4S)</td>
			<td>Fisher Scientific (Sigma-Aldrich)</td>
			<td>BP310-1 (H6147)</td>
			<td>9.53 g</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">Antibiotic/Antimycotic</td>
			<td>Thermo Scientific (Sigma-Aldrich)</td>
			<td>SV3007901 (A5955)</td>
			<td>17-20 mL</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">Gentamicin Sulfate</td>
			<td>Lonza (Sigma-Aldrich)</td>
			<td>BW17-519Z (G1397)</td>
			<td>2-3 mL</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">Donor Equine Sera</td>
			<td>Thermo Scientific (Sigma-Aldrich)</td>
			<td>SH3007403 (H1270)</td>
			<td>75 mL</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">Fetal Bovine Sera</td>
			<td>Thermo Scientific (Sigma-Aldrich)</td>
			<td>SH3007103 (F2442)</td>
			<td>25 mL</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">Collagenase (Type IV)</td>
			<td>Worthington (Sigma-Aldrich)</td>
			<td>LS004189 (C9891)</td>
			<td>0.44 g</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:205px;">Trypsin (from Pancreas)</td>
			<td>MP Biomedicals (Sigma-Aldrich)</td>
			<td>ICN15357125 (T5266)</td>
			<td>1 g</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 2. Consumables, Tools and Equipment</td>
		</tr>
		<tr>
			<td height="42" style="height:43px;width:239px;">Consumable</td>
			<td style="width:204px;">Tools</td>
			<td style="width:199px;">Equipment</td>
			<td></td>
		</tr>
		<tr>
			<td height="28" style="height:28px;">Cell Culture Plates</td>
			<td>Forceps (Coarse)</td>
			<td>Serological Pipettor</td>
			<td></td>
		</tr>
		<tr>
			<td height="28" style="height:28px;width:239px;">Sterile 50 mL Conical Tubes</td>
			<td style="width:204px;">Forceps (Fine)</td>
			<td>pH Meter</td>
			<td></td>
		</tr>
		<tr>
			<td height="28" style="height:28px;width:239px;">Laboratory Tape</td>
			<td style="width:204px;">Scalpel Handles</td>
			<td>Chilling Incubator (Echotherm)</td>
			<td></td>
		</tr>
		<tr>
			<td height="28" style="height:28px;width:239px;">0.2 &#956;m Vacuum Sterilization Systems</td>
			<td style="width:204px;">Scalpel Blades (#10, #11)</td>
			<td>Laminar Flow Hood</td>
			<td></td>
		</tr>
		<tr>
			<td height="28" style="height:28px;width:239px;">Water-repellant Autoclave Paper</td>
			<td style="width:204px;">Surgical Scissors</td>
			<td>Vacuum Manifold</td>
			<td></td>
		</tr>
		<tr>
			<td height="28" style="height:28px;width:239px;">Serological Pipettes</td>
			<td>Glass Petri Dishes</td>
			<td>Microosmolality Meter</td>
			<td></td>
		</tr>
		<tr>
			<td height="28" style="height:28px;width:239px;"></td>
			<td>12-16 G Cannulas with Luer Locks</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 3. Optimized Volumes for Coating Cell Culture Plates</td>
		</tr>
		<tr>
			<td height="24" style="height:24px;width:167px;">Plate Size</td>
			<td style="width:192px;">cm^2 per Well</td>
			<td style="width:132px;">Poly-L-lysine*</td>
			<td style="width:145px;">Laminin**</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;">6 well</td>
			<td>9.5</td>
			<td>1.6 mL</td>
			<td>1</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:167px;">24 well</td>
			<td>1.9</td>
			<td>0.32</td>
			<td>0.2</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:167px;">48 well</td>
			<td>0.95</td>
			<td>0.16</td>
			<td>0.1</td>
		</tr>
		<tr>
			<td height="21" style="height:21px;width:167px;">96 well</td>
			<td>0.32</td>
			<td>0.06</td>
			<td>0.03</td>
		</tr>
		<tr>
			<td height="40" style="height:40px;width:167px;">*0.1 mg/mL concentration</td>
			<td colspan="2">** 0.020 mg/mL concentration</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 4. Media for Isolation, Dissociation, and Culture</td>
		</tr>
		<tr>
			<td height="24" style="height:24px;width:163px;">Reagent</td>
			<td style="width:155px;">Isolation</td>
			<td style="width:127px;">Wash</td>
			<td style="width:127px;">Dissociation</td>
			<td>Complete</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;">Base Medium</td>
			<td>419.25 mL</td>
			<td>395.40 mL</td>
			<td>297.00 mL</td>
			<td>178.00 mL</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;width:163px;">PSF*</td>
			<td>5.00 mL</td>
			<td>4.00 mL</td>
			<td>3.00 mL</td>
			<td>2.00 mL</td>
		</tr>
		<tr>
			<td height="40" style="height:40px;width:163px;">Gentamicin Sulfate**</td>
			<td>0.75 mL</td>
			<td>0.60 mL</td>
			<td>-</td>
			<td>-</td>
		</tr>
		<tr>
			<td height="40" style="height:40px;width:163px;">Donor Equine Serum</td>
			<td>75.00 mL</td>
			<td>-</td>
			<td>-</td>
			<td>-</td>
		</tr>
		<tr>
			<td height="40" style="height:40px;width:163px;">Fetal Bovine Serum***</td>
			<td style="width:155px;">-</td>
			<td>-</td>
			<td>-</td>
			<td>20.00 mL</td>
		</tr>
		<tr>
			<td colspan="4" height="19" style="height:19px;width:660px;">* PSF: penicillin/streptomycin/fungizone cocktail (100x); ** 50 mg/mL concentration; *** Characterized</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 5. Recommended Dilutions and Plating Volumes</td>
		</tr>
		<tr>
			<td height="24" style="height:24px;width:75px;">Plate Size</td>
			<td style="width:103px;">cm^2 per Well</td>
			<td style="width:145px;">Dilution</td>
			<td style="width:111px;">Plating Volume</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;">6 well</td>
			<td>9.5</td>
			<td>1.5-2.0x10^6 cells/mL</td>
			<td>1 mL</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;width:75px;">24 well</td>
			<td>1.9</td>
			<td>1.5-2.0x10^6 cells/mL</td>
			<td>250 &#956;L</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;width:75px;">48 well</td>
			<td>0.95</td>
			<td>1.5-2.0x10^6 cells/mL</td>
			<td>150 &#956;L</td>
		</tr>
		<tr>
			<td height="20" style="height:20px;width:75px;">96 well</td>
			<td>0.32</td>
			<td>1.5-2.0x10^6 cells/mL</td>
			<td>50-100 &#956;L</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 6. Average number of cells per g tissue</td>
		</tr>
		<tr>
			<td colspan="2" height="24" style="height:24px;width:201px;">Species</td>
			<td colspan="2" style="width:273px;">Average # cells/g tissue</td>
		</tr>
		<tr>
			<td colspan="2" height="20" style="height:20px;">Danio rerio</td>
			<td colspan="2">6,400,000</td>
		</tr>
		<tr>
			<td colspan="2" height="20" style="height:20px;width:201px;">Danio dangila</td>
			<td colspan="2">1,783,000</td>
		</tr>
		<tr>
			<td colspan="2" height="20" style="height:20px;width:201px;">Devario aequipinnatus</td>
			<td colspan="2">1,797,000</td>
		</tr>
		<tr>
			<td colspan="2" height="20" style="height:20px;">Oncorhynchus mykiss</td>
			<td colspan="2">66,800</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Table 7. Recommended Incubation Temperatures</td>
		</tr>
		<tr>
			<td colspan="2" height="24" style="height:24px;width:201px;">Species</td>
			<td colspan="2" style="width:273px;">Temperature</td>
		</tr>
		<tr>
			<td colspan="2" height="20" style="height:20px;">Danio/ Devario spp.</td>
			<td colspan="2">26 - 28 &#176;C</td>
		</tr>
		<tr>
			<td colspan="2" height="20" style="height:20px;width:201px;">Oncorhynchus/Salmo spp.</td>
			<td colspan="2">10* - 18 &#176;C</td>
		</tr>
		<tr>
			<td colspan="2" height="20" style="height:20px;width:201px;">Ambystoma mexicanum</td>
			<td colspan="2">18&#176;C</td>
		</tr>
		<tr>
			<td colspan="3" height="20" style="height:20px;">* Lower temperatures support lower proliferation rates.</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of primary myogenic precursor cell/myoblast cultures from basal vertebrate lineages

Due to the inherent difficulty and time involved with studying the myogenic program in vivo, primary culture systems derived from the resident adult stem cells of skeletal muscle, the myogenic precursor cells (MPCs), have proven indispensible to our understanding of mammalian skeletal muscle development and growth. Particularly among the basal taxa of Vertebrata, however, data are limited describing the molecular mechanisms controlling the self-renewal, proliferation, and differentiation of MPCs. Of particular interest are potential mechanisms that underlie the ability of basal vertebrates to undergo considerable postlarval skeletal myofiber hyperplasia (i.e.&#160;teleost fish) and full regeneration following appendage loss (i.e.&#160;urodele amphibians). Additionally, the use of cultured myoblasts could aid in the understanding of regeneration and the recapitulation of the myogenic program and the differences between them. To this end, we describe in detail a robust and efficient protocol (and variations therein) for isolating and maintaining MPCs and their progeny, myoblasts and immature myotubes, in cell culture as a platform for understanding the evolution of the myogenic program, beginning with the more basal vertebrates. Capitalizing on the model organism status of the zebrafish (Danio rerio), we report on the application of this protocol to small fishes of the cyprinid clade Danioninae. In tandem, this protocol can be utilized to realize a broader comparative approach by isolating MPCs from the Mexican axolotl (Ambystomamexicanum) and even laboratory rodents. This protocol is now widely used in studying myogenesis in several fish species, including rainbow trout, salmon, and sea bream1-4.

Twenty-four hours post-seeding, myogenic precursor cells (MPCs) should be visible attached to the laminin substratum (see Figures 1a and 1d). Following seeding, cells (MPCs) adopt a spindle-like shape, indicative of this cell type (Figure 1) and are MyoD1+ (Figure 2). In Danio species, MPCs appear to be more compact with smaller bipolar processes than do MPCs from Oncorhynchus and Salmo species. However, over four days of cultu...

Watch this Scientific Journal Video about Preparation of Primary Myogenic Precursor Cell/Myoblast Cultures from Basal Vertebrate Lineages at JoVE.com

Preparation of Primary Myogenic Precursor Cell/Myoblast Cultures from Basal Vertebrate Lineages

In vitro culture systems have proven indispensible to our understanding of vertebrate myogenesis. However, much remains to be learned about nonmammalian skeletal muscle development and growth, particularly in basal taxa. An efficient and robust protocol for isolating the adult stem cells of this tissue, the myogenic precursor cells (MPCs), and maintaining their self-renewal, proliferation, and differentiation in a primary culture setting allows for the identification of conserved and divergent regulatory mechanisms throughout the vertebrate lineages.

Due to the inherent difficulty and time involved with studying the myogenic program in vivo, primary culture systems derived from the resident adult stem ...

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20.1K vistas.  University of Alabama at Birmingham.  El cultivo in vitro sistemas han demostrado ser indispensables para nuestra comprensión de la miogénesis de vertebrados. Sin embargo, queda mucho por aprender sobre el desarrollo del músculo esquelético no mamífero y el crecimiento, en particular en los taxones basal. Un protocolo eficiente y robusto para el aislamiento de las células madre adultas de este tejido, las células precursoras miogénicas (PSM), y el mantenimiento de su auto-renovación, la pro...