Name: magnetic-activated cell sorting strategies to isolate and purify synovial fluid-derived mesenchymal stem cells from a rabbit model
Uploaded: 2018-08-10T14:00:00
Description: Watch this Scientific Journal Video about Magnetic-Activated Cell Sorting Strategies to Isolate and Purify Synovial Fluid-Derived Mesenchymal Stem Cells from a Rabbit Model at JoVE.com

This study was financially supported by the following grants: the Natural Science Foundation of China (No. 81572198; No. 81772394); the Fund for High Level Medical Discipline Construction of Shenzhen University (No. 2016031638); the Medical Research Foundation of Guangdong Province, China (No. A2016314); and Shenzhen Science and Technology Projects (No. JCYJ20170306092215436; No. JCYJ20170412150609690; No. JCYJ20170413161800287; No. SGLH20161209105517753; No. JCYJ20160301111338144).

All animal experiments were conducted in accordance with the regional Ethics Committee guidelines, and all animal procedures were approved by the Institutional Animal Care and Use Committee of Shenzhen Second People&#39;s Hospital, Shenzhen University.
1. Isolate and Culture the rbSF-MSCs
<ol>
	<li>Preparations for the animal procedure
	<ol>
		<li>Prepare skeletally-mature female New Zealand white rabbits for the collection of rbSF-MSCs. Perform a clinical examination of the...

<ol>
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A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+adipose+tissue+is+a+source+of+multipotent+stem+cells.">Human adipose tissue is a source of multipotent stem cells.</a> Molecular Biology of the Cell. 13 (12), 4279-4295 (2002).</li><li>McGonagle, D., Jones, E., English, A., Emery, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enumeration+and+phenotypic+characterization+of+synovial+fluid+multipotential+mesenchymal+progenitor+cells+in+inflammatory+and+degenerative+arthritis.">Enumeration and phenotypic characterization of synovial fluid multipotential mesenchymal progenitor cells in inflammatory and degenerative arthritis.</a> Arthritis &amp; Rheumatism. 50 (3), 817-827 (2004).</li><li>Jia, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+characterisation+of+human+mesenchymal+stem+cells+derived+from+synovial+fluid+by+magnetic+activated+cell+sorting+(MACS).">Isolation and characterisation of human mesenchymal stem cells derived from synovial fluid by magnetic activated cell sorting (MACS).</a> Cell Biology International. , (2017).</li><li>Bashir, 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=Isolation,+culture+and+characterization+of+New+Zealand+white+rabbit+mesenchymal+stem+cells+derived+from+bone+marrow.">Isolation, culture and characterization of New Zealand white rabbit mesenchymal stem cells derived from bone marrow.</a> Asian Journal of Animal &amp; Veterinary Advances. 10 (8), 13-30 (2015).</li><li>Song, 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=Differentiation+potential+of+rabbit+CD90-positive+cells+sorted+from+adipose-derived+stem+cells+in+vitro.">Differentiation potential of rabbit CD90-positive cells sorted from adipose-derived stem cells in vitro.</a> In Vitro Cellular &amp; Developmental Biology - Animal. 53 (1), 1-6 (2016).</li><li>Lee, T. 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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=Isolation+and+characterization+of+human+mesenchymal+stem+cells+derived+from+synovial+fluid+in+patients+with+osteochondral+lesion+of+the+talus.">Isolation and characterization of human mesenchymal stem cells derived from synovial fluid in patients with osteochondral lesion of the talus.</a> American Journal of Sports Medicine. 43 (2), 399-406 (2015).</li><li>Vereb, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunological+properties+of+synovial+fluid-derived+mesenchymal+stem+cell-like+cells+in+rheumatoid+arthritis.">Immunological properties of synovial fluid-derived mesenchymal stem cell-like cells in rheumatoid arthritis.</a> Annals of the Rheumatic Diseases. 74 (Suppl 1), A64-A65 (2015).</li><li>Matsukura, Y., Muneta, T., Tsuji, K., Koga, H., Sekija, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mesenchymal+stem+cells+in+synovial+fluid+increase+after+meniscus+injury.">Mesenchymal stem cells in synovial fluid increase after meniscus injury.</a> Clinical Orthopaedics &amp; Related Research. 472 (5), 1357-1364 (2014).</li><li>Morito, 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=Synovial+fluid-derived+mesenchymal+stem+cells+increase+after+intra-articular+ligament+injury+in+humans.">Synovial fluid-derived mesenchymal stem cells increase after intra-articular ligament injury in humans.</a> Rheumatology. 47 (8), 1137-1143 (2008).</li><li>Hegewald, A. 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=Hyaluronic+acid+and+autologous+synovial+fluid+induce+chondrogenic+differentiation+of+equine+mesenchymal+stem+cells:+a+preliminary+study.">Hyaluronic acid and autologous synovial fluid induce chondrogenic differentiation of equine mesenchymal stem cells: a preliminary study.</a> Tissue &amp; Cell. 36 (6), 431-438 (2004).</li><li>Jones, E. 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=Synovial+fluid+mesenchymal+stem+cells+in+health+and+early+osteoarthritis:+detection+and+functional+evaluation+at+the+single+cell+level.">Synovial fluid mesenchymal stem cells in health and early osteoarthritis: detection and functional evaluation at the single cell level.</a> Arthritis &amp; Rheumatism. 58 (6), 1731-1740 (2008).</li><li>Makker, K., Agarwal, A., Sharma, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+activated+cell+sorting+(MACS):+utility+in+assisted+reproduction.">Magnetic activated cell sorting (MACS): utility in assisted reproduction.</a> Indian Journal of Experimental Biology. 46 (7), 491-497 (2008).</li><li>Schmitz, 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=Magnetic+activated+cell+sorting+(MACS)+&#8212;+a+new+immunomagnetic+method+for+megakaryocytic+cell+isolation:+comparison+of+different+separation+techniques.">Magnetic activated cell sorting (MACS) &#8212; a new immunomagnetic method for megakaryocytic cell isolation: comparison of different separation techniques.</a> European Journal of Haematology. 52 (5), 267-275 (1994).</li><li>Reinhardt, M., Bader, A., Giri, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Devices+for+stem+cell+isolation+and+delivery:+current+need+for+drug+discovery+and+cell+therapy.">Devices for stem cell isolation and delivery: current need for drug discovery and cell therapy.</a> Expert Review of Medical Devices. 12 (3), 353-364 (2015).</li><li>Gronthos, S., Zannettino, A. C. W., Prockop, D. J., Bunnell, B. A., Phinney, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+to+isolate+and+purify+human+bone+marrow+stromal+stem+cells.">A method to isolate and purify human bone marrow stromal stem cells.</a> Mesenchymal Stem Cells. , 45-57 (2008).</li><li>Krawetz, R. 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=Synovial+fluid+progenitors+expressing+CD90++from+normal+but+not+osteoarthritic+joints+undergo+chondrogenic+differentiation+without+micro-mass+culture.">Synovial fluid progenitors expressing CD90+ from normal but not osteoarthritic joints undergo chondrogenic differentiation without micro-mass culture.</a> PLOS One. 7 (8), e43616 (2012).</li><li>Ogata, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purified+human+synovium+mesenchymal+stem+cells+as+a+good+resource+for+cartilage+regeneration.">Purified human synovium mesenchymal stem cells as a good resource for cartilage regeneration.</a> PLOS One. 10 (6), e0129096 (2015).</li><li>Dominici, 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=Minimal+criteria+for+defining+multipotent+mesenchymal+stromal+cells:+the+International+Society+for+Cellular+Therapy+position+statement.">Minimal criteria for defining multipotent mesenchymal stromal cells: the International Society for Cellular Therapy position statement.</a> Cytotherapy. 8 (4), 315-317 (2006).</li><li>Gauci, S. 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The existence of MSCs in synovial fluid provides an alternative for cell-based therapy. Previous studies have shown that injury sites contain higher amounts of mesenchymal stem cells in their synovial fluid, which may be positively correlated with the post-injury period5. The MSCs in synovial fluid may be beneficial to tissue for enhancing the spontaneous healing after an injury18,19. The clinical application of SF-MSCs has rarely been cov...

MSCs have been suggested as a valuable source for regenerative medicine, especially for cartilage lesions. MSCs, including chondrocytes, osteoblasts, adipocytes, skeletal myocytes, and visceral stromal cells, broadly expand the areas for stem cell transplantation due to their high expansion rate and multi-lineage differentiation potential1. MSCs can be isolated from the skeletal muscle, synovium, bone marrow, and adipose tissue2,3,4. Findings have also con&#64257;rmed the presence of MSCs in synovial fluid, and previous research has identified synovial fluid-derived MSCs (SF-MSCs) as promising candidates for articular regeneration5,6.
However, research and preclinical experimentation on human samples are subject to many ethical issues. Instead, rabbits have been and continue to be the most commonly used animal species to demonstrate that transplantation of MSCs can repair cartilage damage. In recent years, an increasing number of researchers have studied rabbit mesenchymal stem cells (rbMSCs) both in vitro and in vivo, as these cells are similar to human MSCs in their cellular biology and tissue physiology. Similarly, the rbMSCs are capable of adhering to plastic surfaces, displaying spindle-fibroblast morphology as in human MSCs. Furthermore, rabbit mesenchymal samples are simple and easy to obtain7. Additionally, the most crucial points are that rbMSCs express surface markers, such as CD44, CD90, and CD105, and that the multi-lineage differentiation potential is preserved, which is in agreement with the criteria for identification of MSC populations as defined by the International Society for Cellular Therapy8,9. In particular, synovial fluid chondroprogenitors are capable of non-hypertrophic chondrogenesis when induced by TGF-&#946;1, thus making them suitable cell sources for phenotypically articular cartilage regeneration10,11,12.
However, the isolation of SF-MSCs is greatly different from other tissues, including the umbilical cord, adipose tissue, peripheral blood, and bone marrow. Currently, the most common approaches for the purification and sorting of SF-MSCs are flow cytometry and immunomagnetic bead-based sorting, although the flow cytometry method requires a specific environment and highly expensive instruments13.
This article presents a procedure for the simple and minimally invasive collection of samples of synovial fluid from New Zealand white rabbits. During the procedure, the rbSF-MSCs are stably expanded in vitro and then isolated with CD90 positive magnetic bead-based procedures. Finally, the protocol shows how to obtain MSCs with a high purity and viability from the harvested cell sources.
In this protocol, the isolated rbSF-MSCs are characterized based on their morphology, expression of specific markers, and pluripotency for stem cells. Flow cytometry-based immunophenotyping reveals a significant positive expression of CD44 and CD105, whereas the expression of CD45 and CD34 is negative. Finally, an in vitro assay for rbSF-MSCs demonstrates the osteogenic, adipogenic, and chondrogenic differentiation of these cells.

<table>
	<tbody>
		<tr>
			<td>Reagents</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>MesenGro</td>
			<td>StemRD</td>
			<td>MGro-500 1703</td>
			<td>Warm in 37 &#176;C water bath before use</td>
		</tr>
		<tr>
			<td>MesenGro Supplement</td>
			<td>StemRD</td>
			<td>MGro-500 M1512</td>
			<td>Component of MSCs culture medium</td>
		</tr>
		<tr>
			<td>DMEM basic</td>
			<td>Gibco Inc.</td>
			<td>C11995500BT</td>
			<td>MSCs differentiation medium</td>
		</tr>
		<tr>
			<td>Isotonic saline solution</td>
			<td>Litai, China</td>
			<td>5217080305</td>
			<td>Cavity arthrocentesis procedure reagent</td>
		</tr>
		<tr>
			<td>Phosphate-Buffered Saline (PBS)</td>
			<td>HyClone Inc.</td>
			<td>SH30256.01B</td>
			<td>PBS, free of Ca2+/Mg2+</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Gibco Inc.</td>
			<td>10099-141</td>
			<td>Component of MSCs culture medium</td>
		</tr>
		<tr>
			<td>Povidone iodine solution</td>
			<td>Guangdong, China</td>
			<td>150605</td>
			<td>Sterilization agent</td>
		</tr>
		<tr>
			<td>75% ethanol</td>
			<td>Lircon, china</td>
			<td>170917</td>
			<td>Sterilization agent</td>
		</tr>
		<tr>
			<td>0.25% Trypsin/EDTA</td>
			<td>Gibco Inc.</td>
			<td>25200-056</td>
			<td>Cell dissociation reagent</td>
		</tr>
		<tr>
			<td>1% Penicillin-Streptomycin</td>
			<td>Gibco Inc.</td>
			<td>15140-122</td>
			<td>Component of MSCs medium</td>
		</tr>
		<tr>
			<td>MACS Running Buffer</td>
			<td>MiltenyiBiotec</td>
			<td>5160112089</td>
			<td>Containing phosphate-buffered saline (PBS), 0.5% bovine serum albumin(BSA), and 2 mMEDTA</td>
		</tr>
		<tr>
			<td>CD90 antibody conjugated MicroBeads</td>
			<td>MiltenyiBiotec</td>
			<td>5160801456</td>
			<td>For magnetic activated cell sorting</td>
		</tr>
		<tr>
			<td>Sodium pyruvate</td>
			<td>Sigma-Aldrich</td>
			<td>P2256</td>
			<td>Component of MSCs chondrogenic differentiation</td>
		</tr>
		<tr>
			<td>Dexamethasone</td>
			<td>Sigma-Aldrich</td>
			<td>D1756</td>
			<td>Component of MSCs osteogenic differentiation</td>
		</tr>
		<tr>
			<td>ITS</td>
			<td>BD</td>
			<td>354352</td>
			<td>1%, Component of MSCs chondrogenic differentiation</td>
		</tr>
		<tr>
			<td>L-proline</td>
			<td>Sigma-Aldrich</td>
			<td>P5607</td>
			<td>0.35 mM, Component of MSCs chondrogenic differentiation</td>
		</tr>
		<tr>
			<td>L-ascorbic acid-2-phosphate</td>
			<td>Sigma-Aldrich</td>
			<td>A8960</td>
			<td>50 mM, Component of MSCs chondrogenic differentiation</td>
		</tr>
		<tr>
			<td>3-isobutyl-1-methylxanthine</td>
			<td>Sigma-Aldrich</td>
			<td>I5879</td>
			<td>0.5 mM, Component of adipogenic differentiation</td>
		</tr>
		<tr>
			<td>Indomethacin</td>
			<td>Sigma-Aldrich</td>
			<td>I7378</td>
			<td>100 mM, Component of adipogenic differentiation</td>
		</tr>
		<tr>
			<td>TGF&#946;1</td>
			<td>Peprotech</td>
			<td>100-21</td>
			<td>10 ng/mL, Component of MSCs chondrogenic differentiation</td>
		</tr>
		<tr>
			<td>&#945;-glycerophsphate</td>
			<td>Sigma-Aldrich</td>
			<td>G6751</td>
			<td>Component of MSCs osteogenic differentiation</td>
		</tr>
		<tr>
			<td>CD34 Polyclonal Antibody, FITC Conjugated</td>
			<td>Bioss</td>
			<td>bs-0646R-FITC</td>
			<td>Hematopoietic stem cells marker</td>
		</tr>
		<tr>
			<td>Mouse antirabbit CD44</td>
			<td>Bio-Rad</td>
			<td>MCA806GA</td>
			<td>Thy-1 membrane glycoprotein (MSCs marker)</td>
		</tr>
		<tr>
			<td>CD45 (Monoclonal Antibody)</td>
			<td>Bio-Rad</td>
			<td>MCA808GA</td>
			<td>Hematopoietic stem cells marker</td>
		</tr>
		<tr>
			<td>CD105 antibody</td>
			<td>Genetex</td>
			<td>GTX11415</td>
			<td>MSCs marker</td>
		</tr>
		<tr>
			<td>Isopropyl alcohol</td>
			<td>Sigma-Aldrich</td>
			<td>I9030</td>
			<td>Precipitates RNA extraction organic phases</td>
		</tr>
		<tr>
			<td>Trichloromethane</td>
			<td>Wenge, China</td>
			<td>61553</td>
			<td>Extract total RNA</td>
		</tr>
		<tr>
			<td>Trizol</td>
			<td>Invitrogen</td>
			<td>15596-018</td>
			<td>Isolate total RNA</td>
		</tr>
		<tr>
			<td>SYBR green master mix</td>
			<td>Takara Bio, Japan</td>
			<td>RR420A</td>
			<td>PCR test</td>
		</tr>
		<tr>
			<td>cDNA synthesis kit</td>
			<td>Takara Bio, Japan</td>
			<td>RR047A</td>
			<td>Reverse-transcribed to complementary DNA</td>
		</tr>
		<tr>
			<td>Alizarin Red</td>
			<td>Sigma-Aldrich</td>
			<td>A5533</td>
			<td>Staining of calcium compounds</td>
		</tr>
		<tr>
			<td>Toluidine Blue</td>
			<td>Sigma-Aldrich</td>
			<td>89640</td>
			<td>Staining of cartilaginous tissue</td>
		</tr>
		<tr>
			<td>Oil Red O solution</td>
			<td>Sigma-Aldrich</td>
			<td>O1391L</td>
			<td>Lipid vacuole staining</td>
		</tr>
		<tr>
			<td>Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>MiniMACS Separator</td>
			<td>MiltenyiBiotec</td>
			<td>130-042-102</td>
			<td>For magnetic activated cell sorting</td>
		</tr>
		<tr>
			<td>MultiStand</td>
			<td>MiltenyiBiotec</td>
			<td>130-042-303</td>
			<td>For magnetic activated cell sorting</td>
		</tr>
		<tr>
			<td>MS Columns</td>
			<td>MiltenyiBiotec</td>
			<td>130-042-201</td>
			<td>For magnetic activated cell sorting</td>
		</tr>
		<tr>
			<td>Cell Strainer</td>
			<td>FALCON Inc.</td>
			<td>352340</td>
			<td>40 &#956;m nylon</td>
		</tr>
		<tr>
			<td>Hemocytometer</td>
			<td>ISOLAB Inc.</td>
			<td>075.03.001</td>
			<td>Cell counting</td>
		</tr>
		<tr>
			<td>Falcon 100 mm&#160; dish</td>
			<td>Corning</td>
			<td>353003</td>
			<td>Cell culture dish</td>
		</tr>
		<tr>
			<td>Microcentrifuge tube</td>
			<td>Axygen</td>
			<td>MCT-150-C</td>
			<td>RNA Extraction and PCR</td>
		</tr>
		<tr>
			<td>Centrifuge Tubes</td>
			<td>Sigma-Aldrich</td>
			<td>91050</td>
			<td>Gamma-sterilized</td>
		</tr>
		<tr>
			<td>High-speed centrifuge</td>
			<td>Eppendorf</td>
			<td>5804R</td>
			<td>Centrifuge cells</td>
		</tr>
		<tr>
			<td>Carbon dioxide cell incubator</td>
			<td>Thermo scientific</td>
			<td>3111</td>
			<td>Cell culture</td>
		</tr>
		<tr>
			<td>Real-Time PCR Instrument</td>
			<td>Life Tech</td>
			<td>QuantStudio</td>
			<td>Real-Time quantitative polymerase chain reaction</td>
		</tr>
		<tr>
			<td>Flow cytometer</td>
			<td>BD Biosciences</td>
			<td>342975</td>
			<td>Cell analyzer</td>
		</tr>
		<tr>
			<td>Pipettor</td>
			<td>Eppendorf</td>
			<td>O25456F</td>
			<td>Transfer the liquid</td>
		</tr>
		<tr>
			<td>Cloning cylinder</td>
			<td>Sigma-Aldrich</td>
			<td>C3983-50EA</td>
			<td>Isolate and pick individual cell colonies</td>
		</tr>
		<tr>
			<td>Sterile hypodermic syringe</td>
			<td>Double-Dove, China</td>
			<td>131010</td>
			<td>Arthrocentesis procedure</td>
		</tr>
		<tr>
			<td>Rabbit cage</td>
			<td>Zhike, China</td>
			<td>ZC-TGD</td>
			<td>Restrain the rabbit</td>
		</tr>
	</tbody>
</table>

magnetic-activated cell sorting strategies to isolate and purify synovial fluid-derived mesenchymal stem cells from a rabbit model

Mesenchymal stem cells (MSCs) are the main cell source for cell-based therapy. MSCs from articular cavity synovial fluid could potentially be used for cartilage tissue engineering. MSCs from synovial fluid (SF-MSCs) have been considered promising candidates for articular regeneration, and their potential therapeutic benefit has made them an important research topic of late. SF-MSCs from the knee cavity of the New Zealand white rabbit can be employed as an optimized translational model to assess human regenerative medicine. By means of CD90-based magnetic activated cell sorting (MACS) technologies, this protocol successfully obtains rabbit SF-MSCs (rbSF-MSCs) from this rabbit model and further fully demonstrates the MSC phenotype of these cells by inducing them to differentiate to osteoblasts, adipocytes, and chondrocytes. Therefore, this approach can be applied in cell biology research and tissue engineering using simple equipment and procedures.

Isolation, Purification, and Culture of the rbSF-MSCs: 
This protocol uses MACS to isolate rbSF-MSCs, based on the expression of the MSC surface marker CD90. A process flow diagram of rbSF-MSCs&#39; isolation, purification, and characterization and the in vitro culture protocol is shown in Figure 1.
Cell Morphology after Magnetic Activated Cell Sorting (MACS) w...

Watch this Scientific Journal Video about Magnetic-Activated Cell Sorting Strategies to Isolate and Purify Synovial Fluid-Derived Mesenchymal Stem Cells from a Rabbit Model at JoVE.com

Magnetic-Activated Cell Sorting Strategies to Isolate and Purify Synovial Fluid-Derived Mesenchymal Stem Cells from a Rabbit Model

This article presents a simple and economic protocol for the straightforward isolation and purification of mesenchymal stem cells from New Zealand white rabbit synovial fluid.

Mesenchymal stem cells (MSCs) are the main cell source for cell-based therapy. MSCs from articular cavity synovial fluid could potentially be used for ...

This method can help answer key questions in the sorting protocol in the stem cell field by providing a procedure for purifying mesenchymal stem cells directly from synovial fluid. The main advantage of this technique is that we have establish a simple and economic protocol for the isolation and the purification of MACS from rabbit synovial fluid. Generally in the research, due to this method, we make great efforts, because plurating of cell population is dependent on producing a single cell suspension.We first had the idea for this method when we noticed that only the magnetic-activated cell sorting method is currently approved by the FDA for clinical applications. Begin this procedure with animal anesthesia as described in the text protocol. To perform collection of articular synovial fluid from the knee of the rabbit, select an area about five by five centimeters in size around the knee.Shave the rabbit hair from around this area using a safety electric shaver. Alternately, disinfect the procedure site with povidone iodine solution and 75%ethanol three times. Then, apply sterile drapes after area has thoroughly dried.Use a sterile hypodermic syringe to inject one to two milliliters of isotonic saline solution into the knee joint cavity from the lateral articular space. Move the knee three to four times, and then aspirate all the synovial fluid at room temperature. Filter the synovial fluid through a 40 micron nylon cell strainer to remove any debris, within four hours.To culture the rabbit SF-MSCs, collect the filtered fluid in 50 milliliter centrifuge tubes, and centrifuge at 1, 500 rpm for ten minutes at room temperature. Discard the supernatant after the centrifugation and wash the pellet with PBS. After resuspending the pellet with the complete culture medium, plate the medium in 100 milliliter dishes.Incubate the dishes at 37 degrees Celsius in a humidified atmosphere containing 5%carbon dioxide. After 48 hours, replenish the dishes with fresh medium to remove any non-adherent cells. Replace the medium twice a week for two weeks as passage zero.After 14 days following the initial plating, many colonies should've formed in the culture dishes. Select the colonies larger than two millimeters in diameter. Mark where the selected colonies are located, by tracing their circumference on the dish bottom.Discard the colonies less than two millimeters wide using cell scrapers. Digest the selected colonies with about five microliters of 0.25%trypsin using a cloning cylinder, and transfer the colonies to a new dish to passage. When the cells reach about 80%confluency, aspirate the medium.Then, add one to two milliliters of 0.25%trypsin EDTA to each dish. Incubate the dishes for two to three minutes to allow cell detachment. Once the cells are detached, add an equal amount of the culture medium to inactive the trypsin.Pass the cell suspension through a 40 micron cell strainer and collect the filtrate in a 15 milliliter tube. Then spin down the cells at 600 times G for ten minutes at room temperature. Resuspend the cell pellet in MACS Running Buffer.To perform magnetic labeling, determine the cell number using a hemocytometer. Centrifuge the cell suspension at 300 times G for ten minutes at four degrees Celsius. After completely aspirating the supernatant, add 80 microliters of resuspension buffer per ten million total cells.For ten million total cells, add 20 microliters of microbeads conjugated with a monoclonal anti-rabbit CD90 antibody. Mix the magnetic beads and cells evenly in the tubes. Then incubate them at four degrees Celsius for 15 minutes in the dark.Add one milliliter of buffer per ten million cells to the tube, and then centrifuge at 300 times G for ten minutes at four degrees Celsius, to wash the cells. Discard the supernatant after centrifugation. Resuspend the pellet in 500 microliters of buffer per ten million cells.Place the column, with the column wings to the front, into the magnetic field of the magnetic separator. Rinse the magnetic separator column with 500 microliters of the buffer per ten million cells. Transfer the single cell suspension into the column.Let the negative cells pass through the magnetic field to discard these unlabeled cells. Wash the column one to two times with 500 microliter of the buffer per ten million cells, and discard the flow through. Transfer the column into a 15 milliliter centrifuge tube.Add one milliliter of the buffer per ten million cells to the column. Then immediately push the plunger into the column, to flush out the magnetically labeled cells. Repeat the aforementioned procedure with a second magnetic separator column, to increase the purity of CD90-positive cells, which can enrich the eluted fraction.After centrifuging the cell suspension at 300 times G for ten minutes, aspirate the supernatant, and resuspend the pellet with the culture medium. Inoculate the cells in 100 milliliter dishes after the magnetic-activated cell sorting. Incubate the dishes at 37 Celsius in a humidified cell incubator with 5%carbon dioxide.When 80 to 90%confluence of the primary culture is achieved, at about seven to ten days, digest the adherent cells with 0.25%trypsin EDTA and passage them at a one to two dilution to make passage two. Use the same method to pass the cells to passage three, which can be used for the in-vitro assays. Shown here, is the morphology of the monolayer cultured rabbit SF-MSCs before and after MACS, under an inverted microscope.Before sorting, the adherent rabbit synovial fluid cell populations display heterogeneity. They contain diverse cell types and sizes such as oval, long-spindle, short-spindle, and stellate morphology. The main morphology of passage two and passage six, is a spindle morphology.Following MACS with CD90, the cell populations exhibit a homogenous morphology. With the sub culture, the cell number increases. Flow cytometry analysis demonstrated that rabbit SF-MSC cells were positive for the MSC markers CD44 and CD105.While negative for the endothelial cell marker CD34, and for the hematopoietic cell marker CD45. The results showed that before MACS, the rabbit SF-MSC population was composed of approximately 40%MSC cells. After MACS, the enriched population contained greater than 99%MSC cells.Shown here, is flow cytometry analysis of the CD90-positive marker before and after MAC sorting. Alizarin Red staining demonstrated that mineralized nodules formed under osteogenic induction for three weeks. After three weeks of adipogenic induction, accumulation of lipid rich vacuoles was detected by intracellular Oil Red O staining.After tree weeks of chondrogenic induction, the cell pellet was histologically assayed with Toluidine Blue staining. The positive acidic proteoglycan characterized the chondrocyte-like cells. After three weeks of induction, the relative mRNA expression of the osteoblast marker, the adipogenic marker and the chondrogenic marker was detected.Once mastered, this technique can be done in two to four hours. After watching this video, you should have a good understanding of the straight forward isolation and the purification of mesenchymal stem cells from New Zealand white rabbit synovial fluid. While attempting this procedure it's important to remember to select those colonies larger than two milliliters in diameter.Also produce a single cell suspension before immunomagnetic sorting, as unwanted cells attached to a labeled cell will remain on the magnetic bead. Following this procedure, other methods like fluorescence activated cell sorting can be performed in order to answer additional questions addressing the safety and efficacy of purification of mesenchymal stem cells. After it's development, this technique paved the way for researchers in the field of articular cartilage regeneration to explore the ideal CD cells in articular cartilage repair.Don't forget that the operations were performed on arch cooling bench, and the precautions such as gloves, should be always be taken while performing this procedure. The implications of this technique extend towards therapy of articular cartilage injury, because synovial fluid derived MASC are promising candidates for articular cartilage regeneration.

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Research

JoVE Journal

Biology

Isolation and Animal Serum Free Expansion of Human Umbilical Cord Derived Mesenchymal Stromal Cells (MSCs) and Endothelial Colony Forming Progenitor Cells (ECFCs)

The umbilical cord is a rich source for progenitor cells with high proliferative potential including mesenchymal stromal cells (also termed mesenchymal stem cells, MSCs) and endothelial colony forming progenitor cells (ECFCs). Both cell types are key players in maintaining the integrity of tissue and are probably also involved in regenerative processes and tumor formation.
To study their biology and function in a comparative manner it is important to have both cells types available from the same donor. It may also be beneficial for regenerative purposes to derive MSCs and ECFCs from the same tissue.
Because cellular therapeutics should eventually find their way from bench to bedside we established a new method to isolate and further expand progenitor cells without the use of animal protein. Pooled human platelet lysate (pHPL) replaced fetal bovine serum in all steps of our protocol to completely avoid contact of the cells to xenogeneic proteins.
This video demonstrates a methodology for the isolation and expansion of progenitor cells from one umbilical cord.
All materials and procedures will be described.

Isolation and Animal Serum Free Expansion of Human Umbilical Cord Derived Mesenchymal Stromal Cells MSCs and Endothelial Colony Forming Progenitor Cells ECFCs

This protocol describes the isolation and subsequent expansion of mesenchymal stromal cells and endothelial colony forming cells without the use of animal serum to generate autologous pairs for experimental transplantation purposes.

The umbilical cord is a rich source for progenitor cells with high proliferative potential including mesenchymal stromal cells (also termed mesenchymal ...

Lipid Vesicle-mediated Affinity Chromatography using Magnetic Activated Cell Sorting (LIMACS): a Novel Method to Analyze Protein-lipid Interaction

The analysis of lipid protein interaction is difficult because lipids are embedded in cell membranes and therefore, inaccessible to most purification procedures. As an alternative, lipids can be coated on flat surfaces as used for lipid ELISA and Plasmon resonance spectroscopy. However, surface coating lipids do not form microdomain structures, which may be important for the lipid binding properties. Further, these methods do not allow for the purification of larger amounts of proteins binding to their target lipids.
 To overcome these limitations of testing lipid protein interaction and to purify lipid binding proteins we developed a novel method termed lipid vesicle-mediated affinity chromatography using magnetic-activated cell sorting (LIMACS). In this method, lipid vesicles are prepared with the target lipid and phosphatidylserine as the anchor lipid for Annexin V MACS. Phosphatidylserine is a ubiquitous cell membrane phospholipid that shows high affinity to the protein Annexin V. Using magnetic beads conjugated to Annexin V the phosphatidylserine-containing lipid vesicles will bind to the magnetic beads. When the lipid vesicles are incubated with a cell lysate the protein binding to the target lipid will also be bound to the beads and can be co-purified using MACS. This method can also be used to test if recombinant proteins reconstitute a protein complex binding to the target lipid. 
 We have used this method to show the interaction of atypical PKC (aPKC) with the sphingolipid ceramide and to co-purify prostate apoptosis response 4 (PAR-4), a protein binding to ceramide-associated aPKC. We have also used this method for the reconstitution of a ceramide-associated complex of recombinant aPKC with the cell polarity-related proteins Par6 and Cdc42. Since lipid vesicles can be prepared with a variety of sphingo- or phospholipids, LIMACS offers a versatile test for lipid-protein interaction in a lipid environment that resembles closely that of the cell membrane. Additional lipid protein complexes can be identified using proteomics analysis of lipid binding protein co-purified with the lipid vesicles.

Lipid Vesicle-mediated Affinity Chromatography using Magnetic Activated Cell Sorting LIMACS: a Novel Method to Analyze Protein-lipid Interaction

To test the interaction of a protein with its target lipid we used MACS and Annexin V-conjugated magnetic beads and lipid vesicles synthesized from the target lipid and Annexin V-binding phosphatidylserine. Proteins bound to the target lipid are co-purified and analyzed after elution from the beads.

The analysis of lipid protein interaction is difficult because lipids are embedded in cell membranes and therefore, inaccessible to most purification ...

Isolation and Culture of Individual Myofibers and their Satellite Cells from Adult Skeletal Muscle

Muscle regeneration in the adult is performed by resident stem cells called satellite cells. Satellite cells are defined by their position between the basal lamina and the sarcolemma of each myofiber. Current knowledge of their behavior heavily relies on the use of the single myofiber isolation protocol. In 1985, Bischoff described a protocol to isolate single live fibers from the Flexor Digitorum Brevis (FDB) of adult rats with the goal to create an in vitro system in which the physical association between the myofiber and its stem cells is preserved 1. In 1995, Rosenblattmodified the Bischoff protocol such that myofibers are singly picked and handled separately after collagenase digestion instead of being isolated by gravity sedimentation 2, 3. The Rosenblatt or Bischoff protocol has since been adapted to different muscles, age or conditions 3-6. The single myofiber isolation technique is an indispensable tool due its unique advantages. First, in the single myofiber protocol, satellite cells are maintained beneath the basal lamina. This is a unique feature of the protocol as other techniques such as Fluorescence Activated Cell Sorting require chemical and mechanical tissue dissociation 7. Although the myofiber culture system cannot substitute for in vivo studies, it does offer an excellent platform to address relevant biological properties of muscle stem cells. Single myofibers can be cultured in standard plating conditions or in floating conditions. Satellite cells on floating myofibers are subjected to virtually no other influence than the myofiber environment. Substrate stiffness and coating have been shown to influence satellite cells' ability to regenerate muscles 8, 9 so being able to control each of these factors independently allows discrimination between niche-dependent and -independent responses. Different concentrations of serum have also been shown to have an effect on the transition from quiescence to activation. To preserve the quiescence state of its associated satellite cells, fibers should be kept in low serum medium 1-3. This is particularly useful when studying genes involved in the quiescence state. In serum rich medium, satellite cells quickly activate, proliferate, migrate and differentiate, thus mimicking the in vivo regenerative process 1-3. The system can be used to perform a variety of assays such as the testing of chemical inhibitors; ectopic expression of genes by virus delivery; oligonucleotide based gene knock-down or live imaging. This video article describes the protocol currently used in our laboratory to isolate single myofibers from the Extensor Digitorum Longus (EDL) muscle of adult mice (6-8 weeks old).

Isolation and culture of myofibers is the gold standard in vitro system to study the transition of satellite cells through quiescence, activation and differentiation. Importantly, the single myofiber culture system preserves the myofiber/stem cell association, which is an essential component of the muscle stem cell niche.

Muscle  regeneration in the adult is performed by resident stem cells called satellite  cells. Satellite cells are defined by  their position between the ...

Induction and Analysis of Epithelial to Mesenchymal Transition

Epithelial to mesenchymal transition (EMT) is essential for proper morphogenesis during development. Misregulation of this process has been implicated as a key event in fibrosis and the progression of carcinomas to a metastatic state. Understanding the processes that underlie EMT is imperative for the early diagnosis and clinical control of these disease states. Reliable induction of EMT in vitro is a useful tool for drug discovery as well as to identify common gene expression signatures for diagnostic purposes. Here we demonstrate a straightforward method for the induction of EMT in a variety of cell types. Methods for the analysis of cells pre- and post-EMT induction by immunocytochemistry are also included. Additionally, we demonstrate the effectiveness of this method through antibody-based array analysis and migration/invasion assays.

A straightforward method is described for the induction of epithelial to mesenchymal transition (EMT) in a variety of cell types. Methods for the analysis of cells in EMT states by immunocytochemistry are included.

Epithelial  to mesenchymal transition (EMT) is essential for proper morphogenesis during  development. Misregulation of this  process has been implicated ...

Nephrotoxin Microinjection in Zebrafish to Model Acute Kidney Injury

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid decline in renal function and development of the clinical syndrome known as acute kidney injury (AKI). Pharmacological agents used to treat medical circumstances ranging from bacterial infection to cancer, when administered individually or in combination with other drugs, can initiate AKI. Zebrafish are a useful animal model to study the chemical effects on renal function in vivo, as they form an embryonic kidney comprised of nephron functional units that are conserved with higher vertebrates, including humans. Further, zebrafish can be utilized to perform genetic and chemical screens, which provide opportunities to elucidate the cellular and molecular facets of AKI and develop therapeutic strategies such as the identification of nephroprotective molecules. Here, we demonstrate how microinjection into the zebrafish embryo can be utilized as a paradigm for nephrotoxin studies.

Renal injuries incurred from nephrotoxins, which include drugs ranging from antibiotics to chemotherapeutics, can result in complex disorders whose pathogenesis remains incompletely understood. This protocol demonstrates how zebrafish can be used for disease modeling of these conditions, which can be applied to the identification of renoprotective measures.

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid ...

Fluorescence-Activated Cell Sorting for the Isolation of Scleractinian Cell Populations

Coral reefs are under threat due to anthropogenic stressors. The biological response of coral to these stressors may occur at a cellular level, but the mechanisms are not well understood. To investigate coral response to stressors, we need tools for analyzing cellular responses. In particular, we need tools that facilitate the application of functional assays to better understand how cell populations are reacting to stress. In the current study, we use fluorescence-activated cell sorting (FACS) to isolate and separate different cell populations in stony corals. This protocol includes: (1) the separation of coral tissues from the skeleton, (2) creation of a single cell suspension, (3) labeling the coral cells using various markers for flow cytometry, and (4) gating and cell sorting strategies. This method will enable researchers to work on corals at the cellular level for analysis, functional assays, and gene expression studies of different cell populations.

Corals create biodiverse ecosystems important for both humans and marine organisms. However, we still do not understand the full potential and function of many coral cells. Here, we present a protocol developed for the isolation, labeling, and separation of stony coral cell populations.

Coral reefs are under threat due to anthropogenic stressors. The biological response of coral to these stressors may occur at a cellular level, but the ...

Large-Scale Preparation of Synovial Fluid Mesenchymal Stem Cell-Derived Exosomes by 3D Bioreactor Culture

Exosomes secreted by mesenchymal stem cells (MSCs) have been suggested as promising candidates for cartilage injuries and osteoarthritis treatment. Exosomes for clinical application require large-scale production. To this aim, human synovial fluid MSCs (hSF-MSCs) were grown on microcarrier beads, and then cultured in a dynamic three-dimension (3D) culture system. Through utilizing 3D dynamic culture, this protocol successfully obtained large-scale exosomes from SF-MSC culture supernatants. Exosomes were harvested by ultracentrifugation and verified by a transmission electron microscope, nanoparticle transmission assay, and western blotting. Also, the microbiological safety of exosomes was detected. Results of exosome detection suggest that this approach can produce a large number of good manufacturing practices (GMP)-grade exosomes. These exosomes could be utilized in exosome biology research and clinical osteoarthritis treatment.

Here, we present a protocol to produce a large number of GMP-grade exosomes from synovial fluid mesenchymal stem cells using a 3D bioreactor.

Exosomes secreted by mesenchymal stem cells (MSCs) have been suggested as promising candidates for cartilage injuries and osteoarthritis treatment. ...

Isolate Cell-Type-Specific RNAs from Snap-Frozen Heterogeneous Tissue Samples without Cell Sorting

Cellular heterogeneity poses challenges to understanding the function of complex tissues at a transcriptome level. Using cell-type-specific RNAs avoids potential pitfalls caused by the heterogeneity of tissues and unleashes the powerful transcriptome analysis. The protocol described here demonstrates how to use the Translating Ribosome Affinity Purification (TRAP) method to isolate ribosome-bound RNAs from a small amount of EGFP-expressing cells in a complex tissue without cell sorting. This protocol is suitable for isolating cell-type-specific RNAs using the recently available NuTRAP mouse model and could also be used to isolate RNAs from any EGFP-expressing cells.

This protocol aims to isolate cell-type-specific translating ribosomal mRNAs using the NuTRAP mouse model.

Cellular heterogeneity poses challenges to understanding the function of complex tissues at a transcriptome level. Using cell-type-specific RNAs avoids ...

A Simple Benchtop Filtration Method to Isolate Small Extracellular Vesicles from Human Mesenchymal Stem Cells

The ultracentrifugation-based process is considered the common method for small extracellular vesicles (sEVs) isolation. However, the yield from this isolation method is relatively lower, and these methods are inefficient in separating sEV subtypes. This study demonstrates a simple benchtop filtration method to isolate human umbilical cord-derived MSC small extracellular vesicles (hUC-MSC-sEVs), successfully separated by ultrafiltration from the conditioned medium of hUC-MSCs. The size distribution, protein concentration, exosomal markers (CD9, CD81, TSG101), and morphology of the isolated hUC-MSC-sEVs were characterized with nanoparticle tracking analysis, BCA protein assay, western blot, and transmission electron microscope, respectively. The isolated hUC-MSC-sEVs&#39; size was 30-200 nm, with a particle concentration of 7.75 &#215; 1010 particles/mL and a protein concentration of 80 &#181;g/mL. Positive bands for exosomal markers CD9, CD81, and TSG101 were observed. This study showed that hUC-MSC-sEVs were successfully isolated from hUC-MSCs conditioned medium, and characterization showed that the isolated product fulfilled the criteria mentioned by Minimal Information for Studies of Extracellular Vesicles 2018 (MISEV 2018).

This protocol demonstrates how to isolate human umbilical cord-derived mesenchymal stem cells&#39; small extracellular vesicles (hUC-MSC-sEVs) with a simple lab-scale benchtop setting. The size distribution, protein concentration, sEVs markers, and morphology of isolated hUC-MSC-sEVs are characterized by nanoparticle tracking analysis, BCA protein assay, western blot, and transmission electron microscope, respectively.

The ultracentrifugation-based process is considered the common method for small extracellular vesicles (sEVs) isolation. However, the yield from this ...

Fluorescence-Activated Single-Cell Sorting of Human Mesenchymal Stem Cells

Single-Cell Sorting of Immunophenotyped Mesenchymal Stem Cells from Human Exfoliated Deciduous Teeth

The mesenchymal stem cells (MSCs) of an organism possess an extraordinary capacity to differentiate into multiple lineages of adult cells in the body and are known for their immunomodulatory and anti-inflammatory properties. The use of these stem cells is a boon to the field of regenerative biology, but at the same time, a bane to regenerative medicine and therapeutics owing to the multiple cellular ambiguities associated with them. These ambiguities may arise from the diversity in the source of these stem cells and from their in vitro growth conditions, both of which reflect upon their functional heterogeneity.
This warrants methodologies to provide purified, homogeneous populations of MSCs&#160;for therapeutic applications. Advances in the field of flow cytometry have enabled the detection of single-cell populations using a multiparametric approach. This protocol outlines a way to identify and purify&#160;stem cells from&#160;human exfoliated deciduous teeth (SHEDs) through fluorescence-assisted single-cell sorting. Simultaneous expression of surface markers, namely, CD90-fluorescein isothiocyanate (FITC), CD73-peridinin-chlorophyll-protein (PerCP-Cy5.5), CD105-allophycocyanin (APC), and CD44-V450, identified the &#34;bright,&#34; positive-expressors of MSCs&#160;using multiparametric&#160;flow cytometry. However, a significant drop was observed in percentages of quadruple expressors of these positive markers from passage 7 onwards to the later passages.
The immunophenotyped subpopulations were sorted using the single-cell sort mode where only two positive and one negative marker constituted the inclusion criteria. This methodology ensured the cell viability of the sorted populations and maintained cell proliferation post sorting. The downstream application for such sorting can be used to evaluate lineage-specific differentiation for the gated subpopulations. This approach can be applied to other single-cell systems to improve isolation conditions and for acquiring multiple cell surface marker information.

Author Spotlight: Importance of Single Cell Sorting in Isolating Purified Populations of Mesenchymal Stem Cells 

This protocol describes the use of fluorescence-activated cell sorting of human mesenchymal stem cells using the single-cell sorting method. Specifically, the use of single-cell sorting can achieve 99% purity of the immunophenotyped cells from a heterogeneous population when combined with a multiparametric flow cytometry-based approach.

The mesenchymal stem cells (MSCs) of an organism possess an extraordinary capacity to differentiate into multiple lineages of adult cells in the body and ...