This work is supported, in parts, by the National Institutes of Health grants HL-113281 and HL116205 to Paras Kumar Mishra.

The housing, anesthesia, and sacrifice of mice were performed following the approved IACUC protocol of the University of Nebraska Medical Center.
1. Materials
<ol>
	<li>Use 10- to 12-week-old C57BL/6J black male mice, kept in-house at the institutional animal facility, for the isolation of CSCs. CSCs can also be isolated from non-pregnant female mice.</li>
	<li>Sterilize all the necessary surgical instruments, including surgical scissors, fine surgical scissors, curved shank forceps, and a surgical blade, by autoclaving them before the euthanasia of the mouse.</li>
	<li>Prepare CSC isolation buffers in a sterilized condition and store them at 4 &#176;C on ice. These buffers include polysucrose and a sodium diatrizoate solution adjusted to a density of 1.077 g/mL, incomplete Dulbecco&#8217;s modified Eagle&#8217;s Medium, 1x Ham&#8217;s balanced salt solution (HBSS), and cell culture-grade 1x phosphate-buffered saline (PBS). Prepare a 1% collagenase II stock solution (filtered and sterilized) and a 0.2% working solution in HBSS.</li>
	<li>Keep the tissue culture materials in the sterilized condition in the biosafety cabinet, including a 10-mm Petri dish, a 6-well plate, a 24-well plate, T-25 and T-75 culture flasks, 15-mL and 50-mL conical tubes, and disposable serological pipettes with 40-&#181;m and 100-&#181;m cell strainers with 0.22-&#181;m filters.</li>
	<li>Sterilize the 10-&#181;L, 200-&#181;L, and 1,000-&#181;L pipette tips by autoclave.</li>
	<li>Use powder-free nitrile gloves and 70% ethanol to maintain a sterile condition throughout the experiment.</li>
	<li>Use 10% bleach as a disinfectant.</li>
	<li>Use commercially available CSC maintenance medium and cardiomyocytes differentiation medium for the culture and differentiation of CSCs, respectively.</li>
</ol>
2. Isolation Method of Cardiac Stem Cells
<ol>
	<li>Euthanize four to five adult male (or non-pregnant female) mice using a CO2 chamber. Fix each mouse&#8217;s arms on a separate dissection cardboard with pins or sticky tapes.</li>
	<li>Spray 70% ethanol on the mouse to get rid of outside germs and maintain the sterilized condition during the harvesting of the heart. Make an incision with scissors in the middle of the abdomen and cut the skin from the abdomen up to the thorax in a straight line. Remove the skin from both sides of the middle cut to clear the abdominal area of skin and hairs. Using scissors and tweezers, cut the diaphragm below the ribcage.</li>
	<li>Open the thoracic cavity of the mouse by cutting the ribcage inside the hood. Expose the heart and remove the blood near the heart. Wash the surrounding area of the heart with ice-cold PBS to get rid of any blood in the vicinity of the heart.</li>
	<li>Dissect the heart using surgical scissors and tweezers. Place the heart in a 100-mm Petri dish containing 10 mL of ice-cold PBS.</li>
	<li>Palpitate the heart using curved shank forceps and remove the residual blood inside the heart.</li>
	<li>Use the whole heart for the isolation of CSCs.</li>
	<li>Transfer all four or five whole hearts to a 50-mL conical tube containing 10 mL of ice-cold HBSS. Keep the tube on ice until further processing.</li>
	<li>Wipe inside and outside of a biosafety cabinet with 70% ethanol to create a sterilized environment. Sterilize the heart-containing tube and other required materials with 70% ethanol. Place the heart-containing tube into the biosafety cabinet for further processing.</li>
	<li>Transfer the hearts to a 100-mm Petri dish containing 10 mL of ice-cold HBSS. Wash the hearts again by palpating to remove any residual blood inside the heart. Change the HBSS solution after each wash to ensure the complete removal of the blood.</li>
	<li>Cut the hearts into small pieces using fine surgical scissors or a surgical blade in a 100-mm Petri dish containing 5 - 7 mL of HBSS solution. Hold each heart with a pair of forceps and use a pair of surgical fine scissors or a surgical blade to cut the heart into 2- to 4-mm pieces. Change the HBSS solution frequently to ensure blood-free HBSS. Mince the hearts in the HBSS solution.</li>
	<li>Centrifuge the minced tissue at 500 x g at 4 &#176;C for 5 min. Discard the supernatant and keep the pellet.</li>
	<li>Resuspend the pellet in 5 - 6 mL of 0.2% collagenase II solution in a 50-mL conical tube. The volume of collagenase solution should be almost 1.5- to 2-fold to the volume of the pellet. 
	Note: For the digestion of tissue, 0.2% collagenase I and 2.5 U/mL dispase solution can replace 0.2% collagenase II. Use an almost equal volume of dispase solution to the collagenase I solution.</li>
	<li>Thoroughly mix the pellet with 0.2% collagenase II solution by agitating the tube or by rocking the tube on a shaker at 75 x g for 45 - 60 min at 37 &#176;C. Shake the tube vigorously by hand after every 20 - 30 min to enhance the lysis.</li>
	<li>Triturate the lysed tissue mix using&#160;a 5 mL serological pipette and a 1-mL pipette tip to dissociate the tissue lump into the single-cell suspension. 
	Note: To get the maximum recovery of the CSCs, triturate the lysis mix for at least 5 min. If the tissue lumps are relatively big, cut the tip of a 1-mL pipette tip with scissors or a surgical blade and use it for trituration.</li>
	<li>Stop the enzymatic lysis of the tissue by adding commercially available CSC maintenance medium. Add almost 2 - 3x as much maintenance medium as the volume of the lysed tissue in step 2.14.</li>
	<li>Pass the digested cell suspension through a 100-&#181;m cell strainer to remove any undigested tissue pieces.</li>
	<li>Repeat step 2.16 using a 40-&#181;m cell strainer.</li>
	<li>Separate the cells through density gradient centrifugation. For the separation of cells, gently overlay an equal volume of the filtrate over polysucrose and sodium diatrizoate solution. For example, first, add 20 mL of polysucrose and sodium diatrizoate solution in a 50-mL conical tube and then, add 20 mL of filtrate from step 2.17 over the polysucrose and sodium diatrizoate solution. 
	NOTE: Prewarm the polysucrose and sodium diatrizoate solution at 37 &#176;C before use with the cells. Add the filtrate from step 2.17 over the polysucrose and sodium diatrizoate solution very carefully and slowly to avoid any mixing of the two solutions. This is considered to be a crucial step.</li>
	<li>Centrifuge the tube containing both solutions at 500 x g for 20 min at room temperature using a swing bucket centrifuge. Set the centrifuge at a lower acceleration and deceleration speed to avoid mixing the two solutions and for proper separation of the CSCs. This is an important step in CSC isolation. Put the tube containing the gradient mixture very slowly without disturbance inside the centrifuge and set it for centrifugation.</li>
	<li>Take out the buffy coat along with extra solution from the upper layer using either a 1-mL pipette or a plastic Pasteur pipette in a 15-mL sterilized tube. This buffy layer will contain the CSCs. 
	Note: Take extra precaution during the pipetting of the buffy coat not to take out the polysucrose and sodium diatrizoate solution layer because it is toxic to CSCs.</li>
	<li>Add an equal volume of CSC maintenance medium to the cell suspension from step 2.20 and mix it properly to neutralize the residual polysucrose and sodium diatrizoate solution, if present.</li>
	<li>Centrifuge the above cell suspension at 500 x g for 5 min at 4 &#176;C. Discard the supernatant.</li>
	<li>Resuspend the pellet in 7 - 10 mL of incomplete DMEM medium and centrifuge it at 500 x g for 5 min at 4 &#176;C to get rid of any residual polysucrose and sodium diatrizoate solution.</li>
	<li>Collect the pellet, which contains the purified CSCs.</li>
	<li>Resuspend the pellet in 1 mL of CSC maintenance medium, count the CSC number, and use the pellet for culture. To count the CSC number, use Trypan blue staining and a hemocytometer. With four male mice hearts, the yield of CSCs is ~1.8 million.</li>
	<li>Seed the CSCs in a 6-well culture plate coated with a 0.02% gelatin solution containing 0.5% fibronectin. Use 2 mL of complete maintenance medium for seeding. Incubate the culture plate in an incubator at 37 &#176;C with 5% CO2.</li>
	<li>Replace the medium of culture CSCs with complete CSC maintenance medium every day until the third day. After that, change the medium on alternate days.</li>
	<li>Determine the growth of the CSCs by observing them under a microscope.</li>
</ol>
3. Culture Maintenance and Passage of Cardiac Stem Cells
<ol>
	<li>Culture the isolated CSCs in a commercially available maintenance medium. Replace the culture medium with fresh maintenance medium on alternate days. When the CSC culture has reached confluency, transfer the CSCs to a new plate coated with gelatin and fibronectin, as mentioned in step 2.26. Detach the cultured CSCs by enzymatic cell dissociation buffer. Follow the standard protocol of cell dissociation from the culture plate. At this stage, CSCs are considered at passage 0 (P0) stage.</li>
	<li>Culture P0 CSCs in a new gelatin and fibronectin-coated plate in complete CSC maintenance medium at 37 &#176;C in a 5% CO2 incubator, allow them to be confluent, and then follow step 3.1 to get passage 1 (P1) CSCs. Store P1 CSCs in liquid nitrogen or use them for experiments.</li>
	<li>Seed 0.5 million cells in a 6-well plate or 1 million cells in T-25 to maintain the CSC culture at its initial stage.</li>
	<li>Passage the CSCs when they become 85% - 90% confluent. CSCs can be cultured in the maintenance medium up to four to six weeks. 
	Note: Keep the initial seeding density of the CSCs relatively high (40% - 50%) because, at a lower seeding density, the CSCs may change their morphology to flat and elongated.</li>
</ol>
4. Characterization of Cardiac Stem Cells
<ol>
	<li>To characterize the cultured CSCs, observe them under a phage-contrast or a bright-field microscope. Place the CSC-containing plate on the objective of a fluorescent microscope. Set the magnification fairly low (10X) to focus the cells. Use phase-contrast aperture to observe the cells. Increase the magnification to 20X by changing the objective lens and image the CSCs. Increase the objective to 40X and image the CSCs. In two days, the CSCs appear almost round in shape, but the size of the cell increases with time, and in seven days, the CSCs appear almost cylindrical in shape (Figure&#160;1A - 1C).</li>
	<li>Perform immunostaining of the CSCs with markers of pluripotency/stemness (OCT4, SOX2, or Nanog), proliferation (Ki-67) (Figure&#160;2A - 2D), and cardiac origin/progenitor cells (Sca-1, NKX2-5, or GATA4) (Figure&#160;3A - 3C).
	<ol>
		<li>For the immunostaining of the CSCs, seed 10,000 CSCs in a 24-well culture plate.</li>
		<li>The next day (after 18 - 24 h), fix the CSCs in 300 &#181;L of 4% paraformaldehyde for 10 min.</li>
		<li>Wash the CSCs with 500 &#181;L of ice-cold PBS, 3x with 5-min intervals.</li>
		<li>Permeabilize the CSCs with 300 &#181;L of 0.2% Triton X-100 diluted in PBS for 10 min.</li>
		<li>Wash the CSCs with 500 &#181;L of ice-cold PBS, 3x with 5-min intervals.</li>
		<li>Perform the blocking of the CSCs with 300 &#181;L of 1% BSA diluted in PBST (PBS + 0.1% Tween 20) or 300 &#181;L of 10% normal chicken serum diluted in PBST for 1 h.</li>
		<li>Incubate the CSCs in 200 &#181;L of primary antibody diluted in blocking solution overnight at 4 &#176;C. Dilute the primary antibody as recommended by the datasheet of antibodies or as per standardization.</li>
		<li>Wash the CSCs with 500 &#181;L of ice-cold PBS, 3x with 5-min intervals.</li>
		<li>Incubate the CSCs in 200 &#181;L of secondary antibody diluted in blocking solution (see step 4.2.6) for 1 h at room temperature. Dilute the secondary antibody as recommended by the datasheet of antibodies or as per standardization.</li>
		<li>Wash the CSCs with 500 &#181;L of ice-cold PBS, 3x with 5-min intervals.</li>
		<li>Counterstain the CSCs with 200 &#181;L of DAPI (1 &#181;g/mL) diluted in PBS for 5 min.</li>
		<li>Wash the CSCs 1x with 500 &#181;L of ice-cold PBS. Then, add 300 &#181;L of ice-cold PBS in each well.</li>
		<li>Perform imaging using a fluorescence microscope. Follow the instructions of fluorescent imaging, such as to avoid direct light on the plate. Keep the culture plate under the microscope. Focus the cells at different magnifications. Observe the cells under phase-contrast and/or different excitation filters and save the images.</li>
		<li>Store the plate in the dark at 4 &#176;C.</li>
	</ol>
	</li>
</ol>
5. Differentiation of Cardiac Stem Cells into Cardiomyocyte
<ol>
	<li>For the differentiation of CSCs, seed 500,000 CSCs in a 6-well plate with 2&#160;mL of prewarm (37 &#176;C) commercially available CSC maintenance medium.</li>
	<li>Incubate the plate containing the CSCs in a CO2 incubator at 37 &#176;C. Allow the CSCs to attach and proliferate until sub-confluent growth. If the medium turns yellow, replace the culture medium with fresh maintenance medium.</li>
	<li>At 85% - 90% confluency, replace the maintenance medium with 2 mL of prewarm (37 &#176;C) cardiomyocytes differentiation medium. Incubate the plate in a CO2 incubator at 37 &#176;C for up to 2 - 3 weeks.</li>
	<li>Change the differentiation medium every 2 - 3 d. Observe the CSCs&#8217; morphology under a microscope every time during the medium change to ensure the good culture conditions.</li>
	<li>After 12 d of CSC culture in differentiation medium, image the CSCs for differentiation markers following a standard immunostaining protocol (see steps 4.2.1 - 4.2.14). Save the fluorescent images for the expression of cardiomyocytes markers (Figure&#160;4A - 4B).</li>
</ol>

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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=Isolation+and+characterization+of+resident+endogenous+c-Kit++cardiac+stem+cells+from+the+adult+mouse+and+rat+heart.">Isolation and characterization of resident endogenous c-Kit+ cardiac stem cells from the adult mouse and rat heart.</a> Nature Protocols. 9, 1662-1681 (2014).</li><li>Rutering, 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=Improved+Method+for+Isolation+of+Neonatal+Rat+Cardiomyocytes+with+Increased+Yield+of+C-Kit++Cardiac+Progenitor+Cells.">Improved Method for Isolation of Neonatal Rat Cardiomyocytes with Increased Yield of C-Kit+ Cardiac Progenitor Cells.</a> Journal of Stem Cell Research and Therapy. 5, 1-8 (2015).</li><li>Saravanakumar, M., Devaraj, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distribution+and+homing+pattern+of+c-kit++Sca-1++CXCR4++resident+cardiac+stem+cells+in+neonatal,+postnatal,+and+adult+mouse+heart.">Distribution and homing pattern of c-kit+ Sca-1+ CXCR4+ resident cardiac stem cells in neonatal, postnatal, and adult mouse heart.</a> Cardiovascular Pathology. 22, 257-263 (2013).</li><li>Monsanto, M. 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=Concurrent+Isolation+of+3+Distinct+Cardiac+Stem+Cell+Populations+From+a+Single+Human+Heart+Biopsy.">Concurrent Isolation of 3 Distinct Cardiac Stem Cell Populations From a Single Human Heart Biopsy.</a> Circulation Research. 121, 113-124 (2017).</li><li>Vidyasekar, P., Shyamsunder, P., Santhakumar, R., Arun, R., Verma, 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=A+simplified+protocol+for+the+isolation+and+culture+of+cardiomyocytes+and+progenitor+cells+from+neonatal+mouse+ventricles.">A simplified protocol for the isolation and culture of cardiomyocytes and progenitor cells from neonatal mouse ventricles.</a> European Journal of Cell Biology. 94, 444-452 (2015).</li><li>Dergilev, K. V., 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=Comparison+of+cardiac+stem+cell+sheets+detached+by+Versene+solution+and+from+thermoresponsive+dishes+reveals+similar+properties+of+constructs.">Comparison of cardiac stem cell sheets detached by Versene solution and from thermoresponsive dishes reveals similar properties of constructs.</a> Tissue Cell. 49, 64-71 (2017).</li><li>Zaruba, M. M., Soonpaa, M., Reuter, S., Field, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiomyogenic+potential+of+C-kit(+)-expressing+cells+derived+from+neonatal+and+adult+mouse+hearts.">Cardiomyogenic potential of C-kit(+)-expressing cells derived from neonatal and adult mouse hearts.</a> Circulation. 121, 1992-2000 (1992).</li><li>Wang, H., 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+a+Sca-1+/CD31-+progenitor+cell+lineage+derived+from+mouse+heart+tissue.">Isolation and characterization of a Sca-1+/CD31- progenitor cell lineage derived from mouse heart tissue.</a> BMC Biotechnology. 14, 75 (2014).</li><li>Smits, A. 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=Human+cardiomyocyte+progenitor+cells+differentiate+into+functional+mature+cardiomyocytes:+an+in+vitro+model+for+studying+human+cardiac+physiology+and+pathophysiology.">Human cardiomyocyte progenitor cells differentiate into functional mature cardiomyocytes: an in vitro model for studying human cardiac physiology and pathophysiology.</a> Nature Protocols. 4, 232-243 (2009).</li></ol>

The authors have nothing to disclose.

The critical steps of this CSC isolation protocol are as follows. 1) A sterilized condition must be maintained for extraction of the hearts from the mice. Any contamination during the heart extraction may compromise the quality of the CSCs. 2) The blood must be completely removed before mincing the heart, which is done by several washes of the whole heart and the heart pieces with HBSS solution. 3) The heart pieces must be completely lysed into a single-cell suspension with collagenase solution. 4) The polysucrose and so...

Ischemic heart disease, including myocardial infarction (MI), is a major cause of death around the world1. Stem cell therapy for regenerating dead myocardium remains a major approach to improve the cardiac function of an MI heart2,3,4,5. Different types of stem cells have been used to replenish dead myocardium and to improve the cardiac function of an MI heart. They can be broadly categorized into embryonic stem cells6 and adult stem cells. In adult stem cells, various types of stem cells have been used, such as bone marrow-derived mononuclear cells7,8, mesenchymal stem cells derived from bone marrow9,10, adipose tissue11,12, and umbilical cord13, and CSCs14,15. Stem cells can promote cardiac regeneration through endocrine and/or paracrine actions16,17,18,19,20. However, a major limitation of stem cell therapy is obtaining an adequate number of stem cells that can proliferate and/or differentiate toward a specific cardiac lineage21,22. Autologous and allogenic transplantation of stem cells is an important challenge in stem cell therapy9. CSCs could be a better approach for cardiac regeneration because they are derived from the heart and they can be more easily differentiated into cardiac lineages than non-cardiac stem cells. Thus, it reduces the risk of teratoma. In addition, the endocrine and paracrine effects of CSCs, such as exosomes and miRNAs derived from the CSCs, could be more effective than other types of stem cells. Thus, CSCs remains a better option for cardiac regeneration23,24.
Although CSCs are a better candidate for cardiac regeneration in an MI heart due to their cardiac origin, a major limitation with CSCs is less yield due to the lack of an efficient isolation method. Another limitation could be the impaired differentiation of CSCs toward cardiomyocytes lineage2,25,26,27. To circumvent these limitations, it is important to develop an efficient protocol for CSC isolation, characterization, and differentiation towards cardiac lineage. There is no single acceptable marker for CSCs and a specific cell-surface marker-based isolation of CSCs yields less CSCs. Here, we standardize a simple gradient centrifugation approach to isolate CSCs from the mouse heart that is cost-effective and results in an increased yield of CSCs. These isolated CSCs can be selected for specific cell-surface markers by fluorescence-activated cell shorting. In addition to CSCs isolation, we provided a protocol for CSC culture, characterization, and differentiation towards cardiomyocyte lineage. Thus, we present an elegant method to isolate, characterize, culture, and differentiate CSCs from adult mouse hearts (Figure 5).

<table>
	<tbody>
		<tr>
			<td>Mice</td>
			<td>The Jackson laboratory, USA</td>
			<td>Stock no. 000664</td>
			<td></td>
		</tr>
		<tr>
			<td>Antibodies:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>OCT4-</td>
			<td>Abcam</td>
			<td>ab18976 (rabbit polyclonal)</td>
			<td>OCT4-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>SOX2</td>
			<td>Abcam</td>
			<td>ab97959 (rabbit polyclonal)</td>
			<td>SOX2-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>Nanog</td>
			<td>Abcam</td>
			<td>ab80892 (rabbit polyclonal)</td>
			<td>Nanog-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>Ki67</td>
			<td>Abcam</td>
			<td>ab16667 (rabbit polyclonal)</td>
			<td>Ki67-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>Sca I</td>
			<td>Millipore</td>
			<td>AB4336 (rabbit polyclonal)</td>
			<td>Sca I Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>NKX2-5</td>
			<td>Santa Cruz</td>
			<td>sc-8697 (goat polyclonal)</td>
			<td>NKX2-5-Primary antibody- 1:50 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>GATA4</td>
			<td>Abcam</td>
			<td>ab84593 (rabbit polyclonal)</td>
			<td>GATA4-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>MEF2C</td>
			<td>Santa Cruz</td>
			<td>sc-13268 (goat polyclonal)</td>
			<td>MEF2C-Primary antibody- 1:50 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>Troponin I</td>
			<td>Millipore</td>
			<td>MAB1691 (mouse monoclonal)</td>
			<td>Troponin I-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>Actinin</td>
			<td>Millipore</td>
			<td>MAB1682 (mouse monoclonal)</td>
			<td>Actinin-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>ANP</td>
			<td>Millipore</td>
			<td>AB5490 (mouse polyclonal)</td>
			<td>ANP-Primary antibody- 1:100 dilution, Secondar antibody- 1:200 dilution, in blocking solution</td>
		</tr>
		<tr>
			<td>Alex Fluor-488 checken anti-rabbit</td>
			<td>Life technology</td>
			<td>Ref no. A21441</td>
			<td></td>
		</tr>
		<tr>
			<td>Alex Fluor-594 goat anti-rabbit</td>
			<td>Life technology</td>
			<td>Ref no. A11012</td>
			<td></td>
		</tr>
		<tr>
			<td>Alex Fluor-594 rabbit anti-goat</td>
			<td>Life technology</td>
			<td>Ref no. A11078</td>
			<td></td>
		</tr>
		<tr>
			<td>Alex Fluor-488 checken anti-mouse</td>
			<td>Life technology</td>
			<td>Ref no. A21200</td>
			<td></td>
		</tr>
		<tr>
			<td>Alex Fluor-594 checken anti-goat</td>
			<td>Life technology</td>
			<td>Ref no. A21468</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Culture medium: </td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>CSC maintenance medium</td>
			<td>Millipore</td>
			<td>SCM101</td>
			<td>Note: For CSC culture, PBS or incomplete DMEM medium was used for washing the cells</td>
		</tr>
		<tr>
			<td>cardiomyocytes differentiation medium</td>
			<td>Millipore</td>
			<td>SCM102</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Sigma-Aldrich</td>
			<td>D5546</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Cell Isolation buffer:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>polysucrose and sodium diatrizoate solution (Histopaque1077)</td>
			<td>Sigma</td>
			<td>10771</td>
			<td></td>
		</tr>
		<tr>
			<td>HBSS</td>
			<td>Gibco</td>
			<td>2018-03</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase I</td>
			<td>Sigma</td>
			<td>C0130</td>
			<td></td>
		</tr>
		<tr>
			<td>Dispase solution</td>
			<td>STEMCELL Technologies</td>
			<td>7913</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>LONZA</td>
			<td>S1226</td>
			<td></td>
		</tr>
		<tr>
			<td>StemPro Accutase Cell Dissociation Reagent</td>
			<td>Thermoscientific</td>
			<td>A1110501</td>
			<td></td>
		</tr>
		<tr>
			<td>Other reagents:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>BSA</td>
			<td>Sigma</td>
			<td>A7030</td>
			<td></td>
		</tr>
		<tr>
			<td>Normal checken serum</td>
			<td>Vector laboratory</td>
			<td>S3000</td>
			<td></td>
		</tr>
		<tr>
			<td>DAPI solution</td>
			<td>Applichem</td>
			<td>A100,0010</td>
			<td>Dapi, working concentration-1 &#181;g/mL</td>
		</tr>
		<tr>
			<td>Trypan blue</td>
			<td>Biorad</td>
			<td>145-0013</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin</td>
			<td>Sigma</td>
			<td>T4049</td>
			<td></td>
		</tr>
		<tr>
			<td>StemPro Accutase Cell Dissociation Reagent</td>
			<td>Thermo Fisher Scientific</td>
			<td>A1110501</td>
			<td></td>
		</tr>
		<tr>
			<td>Formaldehyde</td>
			<td>Sigma</td>
			<td>158127</td>
			<td></td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>ACROS</td>
			<td>Cas No. 900-293-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Tween 20</td>
			<td>Fisher Sceintific</td>
			<td>Lot No. 160170</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Tissue culture materials:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>100 mm petri dish</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>6-well plate</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>24-well plate</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>T-25 flask</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>T-75 flask</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>15 ml conical tube</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>50 mL conical tube</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>40 &#181;m cell stainer</td>
			<td>Fisher Scientific</td>
			<td>22363547</td>
			<td></td>
		</tr>
		<tr>
			<td>100 &#181;m cell stainer</td>
			<td>Fisher Scientific</td>
			<td>22363549</td>
			<td></td>
		</tr>
		<tr>
			<td>0.22 &#181;m filter</td>
			<td>Fisher Scientific</td>
			<td>09-719C</td>
			<td></td>
		</tr>
		<tr>
			<td>10 mL syring</td>
			<td>BD</td>
			<td>Ref no. 309604</td>
			<td></td>
		</tr>
		<tr>
			<td>10 &#181;L, 200 &#181;L, 1000 &#181;L pipette tips</td>
			<td>Fisher Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>5 mL, 10mL, 25 mL disposible plastic pipette</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Instruments</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Centrufuge machine</td>
			<td>Thermo Scientific</td>
			<td>LEGEND X1R centrifuge</td>
			<td></td>
		</tr>
		<tr>
			<td>EVOS microscope</td>
			<td>Life technology</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Automated cell counter</td>
			<td>Biorad</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cell counting slide</td>
			<td>Biorad</td>
			<td>145-0011</td>
			<td></td>
		</tr>
		<tr>
			<td>Pippte aid</td>
			<td>Thermo Scientific</td>
			<td>S1 pipet filler</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Surgical Instruments:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical scissors</td>
			<td>Fine Scientific Tool</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fine surgical scissors</td>
			<td>Fine Scientific Tool</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Curve shank forceps</td>
			<td>Fine Scientific Tool</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical blade</td>
			<td>Fine Scientific Tool</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

isolation, characterization, and differentiation of cardiac stem cells from the adult mouse heart

Myocardial infarction (MI) is a leading cause of morbidity and mortality around the world. A major goal of regenerative medicine is to replenish the dead myocardium after MI. Although several strategies have been used to regenerate myocardium, stem cell therapy remains a major approach to replenish the dead myocardium of an MI heart. Accumulating evidence suggests the presence of resident cardiac stem cells (CSCs) in the adult heart and their endocrine and/or paracrine effects on cardiac regeneration. However, CSC isolation and their characterization and differentiation toward myocardial cells, especially cardiomyocytes, remains a technical challenge. In the present study, we provided a simple method for the isolation, characterization, and differentiation of CSCs from the adult mouse heart. Here, we describe a density gradient method for the isolation of CSCs, where the heart is digested by a 0.2% collagenase II solution. To characterize the isolated CSCs, we evaluated the expression of CSCs/cardiac markers Sca-1, NKX2-5, and GATA4, and pluripotency/stemness markers OCT4, SOX2, and Nanog. We also determined the proliferation potential of isolated CSCs by culturing them in a Petri dish and assessing the expression of the proliferation marker Ki-67. For evaluating the differentiation potential of CSCs, we selected seven- to ten-days cultured CSCs. We transferred them to a new plate with a cardiomyocyte differentiation medium. They are incubated in a cell culture incubator for 12 days, while the differentiation medium is changed every three days. The differentiated CSCs express cardiomyocyte-specific markers: actinin and troponin I. Thus, CSCs isolated with this protocol have stemness and cardiac markers, and they have a potential for proliferation and differentiation toward cardiomyocyte lineage.

In the present study, we isolated CSCs from 10- to 12-week-old C57BL/6J male mice hearts. Here, we have presented a simple method for CSC isolation and characterization using markers of pluripotency. We also presented an elegant method for CSC differentiation and the characterization of CSCs that differentiated toward cardiomyocytes lineage. We observed a spindle shape morphology of 2- to 3-days-cultured CSCs under a phase-contrast microscope (Figure&#160;1A ...

Watch this Scientific Journal Video about Isolation, Characterization, and Differentiation of Cardiac Stem Cells from the Adult Mouse Heart at JoVE.com

Isolation, Characterization, and Differentiation of Cardiac Stem Cells from the Adult Mouse Heart

The overall goal of this article is to standardize the protocol for the isolation, characterization, and differentiation of cardiac stem cells (CSCs) from the adult mouse heart. Here, we describe a density gradient centrifugation method to isolate murine CSCs and elaborated methods for CSC culture, proliferation, and differentiation into cardiomyocytes.

Myocardial infarction (MI) is a leading cause of morbidity and mortality around the world. A major goal of regenerative medicine is to replenish the dead ...

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6.5K Views.  University of Nebraska Medical Center. The overall goal of this article is to standardize the protocol for the isolation, characterization, and differentiation of cardiac stem cells (CSCs) from the adult mouse heart. Here, we describe a density gradient centrifugation method to isolate murine CSCs and elaborated methods for CSC culture, proliferation, and differentiation into cardiomyocytes.

Video: Isolation, Characterization, and Differentiation of Cardiac Stem Cells from the Adult Mouse Heart

Isolation of Retinal Stem Cells from the Mouse Eye

The adult mouse retinal stem cell (RSC) is a rare quiescent cell found within the ciliary epithelium (CE) of the mammalian eye1,2,3. The CE is made up of non-pigmented inner and pigmented outer cell layers, and the clonal RSC colonies that arise from a single pigmented cell from the CE are made up of both pigmented and non-pigmented cells which can be differentiated to form all the cell types of the neural retina and the RPE. There is some controversy about whether all the cells within the spheres all contain at least some pigment4; however the cells are still capable of forming the different cell types found within the neural retina1-3. In some species, such as amphibians and fish, their eyes are capable of regeneration after injury5, however; the mammalian eye shows no such regenerative properties. We seek to identify the stem cell in vivo and to understand the mechanisms that keep the mammalian retinal stem cells quiescent6-8, even after injury as well as using them as a potential source of cells to help repair physical or genetic models of eye injury through transplantation9-12. Here we describe how to isolate the ciliary epithelial cells from the mouse eye and grow them in culture in order to form the clonal retinal stem cell spheres. Since there are no known markers of the stem cell in vivo, these spheres are the only known way to prospectively identify the stem cell population within the ciliary epithelium of the eye.

In this video, we will demonstrate how to isolate retinal stem cells from the ciliary epithelium of the mouse eye and grow them in culture to form clonal retinal spheres. The spheres that are isolated possess the cardinal properties of stem cells: self-renewal and multipotentiality.

The adult mouse retinal stem cell (RSC) is a rare quiescent cell found within the ciliary epithelium (CE) of the mammalian eye1,2,3. The CE is made up of ...

Isolation and Culture of Adult Epithelial Stem Cells from Human Skin

The homeostasis of all self-renewing tissues is dependent on adult stem cells. As undifferentiated stem cells undergo asymmetric divisions, they generate daughter cells that retain the stem cell phenotype and transit-amplifying cells (TA cells) that migrate from the stem cell niche, undergo rapid proliferation and terminally differentiate to repopulate the tissue.
Epithelial stem cells have been identified in the epidermis, hair follicle, and intestine as cells with a high in vitro proliferative potential and as slow-cycling label-retaining cells in vivo 1-3. Adult, tissue-specific stem cells are responsible for the regeneration of the tissues in which they reside during normal physiologic turnover as well as during times of stress 4-5. Moreover, stem cells are generally considered to be multi-potent, possessing the capacity to give rise to multiple cell types within the tissue 6. For example, rodent hair follicle stem cells can generate epidermis, sebaceous glands, and hair follicles 7-9. We have shown that stem cells from the human hair follicle bulge region exhibit multi-potentiality 10.
Stem cells have become a valuable tool in biomedical research, due to their utility as an in vitro system for studying developmental biology, differentiation, tumorigenesis and for their possible therapeutic utility. It is likely that adult epithelial stem cells will be useful in the treatment of diseases such as ectodermal dysplasias, monilethrix, Netherton syndrome, Menkes disease, hereditary epidermolysis bullosa and alopecias 11-13. Additionally, other skin problems such as burn wounds, chronic wounds and ulcers will benefit from stem cell related therapies 14,15. Given the potential for reprogramming of adult cells into a pluripotent state (iPS cells)16,17, the readily accessible and expandable adult stem cells in human skin may provide a valuable source of cells for induction and downstream therapy for a wide range of disease including diabetes and Parkinson's disease.

A rapid, robust way of isolating viable adult epithelial stem cells from human skin is described. The method utilizes enzymatic digestion of skin collagen matrix , followed by plucking of hair follicles and isolation of single cell suspensions or tissue fragments for cell culture.

The homeostasis of all self-renewing tissues is dependent on adult stem cells. As undifferentiated stem cells undergo asymmetric divisions, they generate ...

Isolation &#38; Characterization of Hoechstlow CD45negative Mouse Lung Mesenchymal Stem Cells

Tissue resident mesenchymal stem cells (MSC) are important regulators of tissue repair or regeneration, fibrosis, inflammation, angiogenesis and tumor formation. Taken together these studies suggest that resident lung MSC play a role during pulmonary tissue homeostasis, injury and repair during diseases such as pulmonary fibrosis (PF) and arterial hypertension (PAH). Here we describe a technology to define a population of resident lung MSC. The definition of this population in vivo pulmonary tissue using a define set of markers facilitates the repeated isolation of a well-characterized stem cell population by flow cytometry and the study of a specific cell type and function.

Isolation & Characterization of Hoechstlow CD45negative Mouse Lung Mesenchymal Stem Cells

In this article we demonstrate the isolation of murine resident lung mesenchymal stem cells (lung MSC), their expansion, characterization and analysis of immunomodulatory properties.

Tissue resident mesenchymal stem cells (MSC) are important regulators of tissue repair or regeneration, fibrosis, inflammation, angiogenesis and tumor ...

Generation of Mice Derived from Induced Pluripotent Stem Cells

The production of induced pluripotent stem cells (iPSCs) from somatic cells provides a means to create valuable tools for basic research and may also produce a source of patient-matched cells for regenerative therapies. iPSCs may be generated using multiple protocols and derived from multiple cell sources. Once generated, iPSCs are tested using a variety of assays including immunostaining for pluripotency markers, generation of three germ layers in embryoid bodies and teratomas, comparisons of gene expression with embryonic stem cells (ESCs) and production of chimeric mice with or without germline contribution2. Importantly, iPSC lines that pass these tests still vary in their capacity to produce different differentiated cell types2. This has made it difficult to establish which iPSC derivation protocols, donor cell sources or selection methods are most useful for different applications.
The most stringent test of whether a stem cell line has sufficient developmental potential to generate all tissues required for survival of an organism (termed full pluripotency) is tetraploid embryo complementation (TEC)3-5. Technically, TEC involves electrofusion of two-cell embryos to generate tetraploid (4n) one-cell embryos that can be cultured in vitro to the blastocyst stage6. Diploid (2n) pluripotent stem cells (e.g. ESCs or iPSCs) are then injected into the blastocoel cavity of the tetraploid blastocyst and transferred to a recipient female for gestation (see Figure 1). The tetraploid component of the complemented embryo contributes almost exclusively to the extraembryonic tissues (placenta, yolk sac), whereas the diploid cells constitute the embryo proper, resulting in a fetus derived entirely from the injected stem cell line.
Recently, we reported the derivation of iPSC lines that reproducibly generate adult mice via TEC1. These iPSC lines give rise to viable pups with efficiencies of 5-13%, which is comparable to ESCs3,4,7 and higher than that reported for most other iPSC lines8-12. These reports show that direct reprogramming can produce fully pluripotent iPSCs that match ESCs in their developmental potential and efficiency of generating pups in TEC tests. At present, it is not clear what distinguishes between fully pluripotent iPSCs and less potent lines13-15. Nor is it clear which reprogramming methods will produce these lines with the highest efficiency. Here we describe one method that produces fully pluripotent iPSCs and "all- iPSC" mice, which may be helpful for investigators wishing to compare the pluripotency of iPSC lines or establish the equivalence of different reprogramming methods.

Generating induced pluripotent stem cell (iPSC) lines produces lines of differing developmental potential even when they pass standard tests for pluripotency. Here we describe a protocol to produce mice derived entirely from iPSCs, which defines the iPSC lines as possessing full pluripotency1.

The production of induced pluripotent stem cells (iPSCs) from somatic cells provides a means to create valuable tools for basic research and may also ...

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 ...

Na&iuml;ve Adult Stem Cells Isolation from Primary Human Fibroblast Cultures

Over the last decade, several adult stem cell populations have been identified in human skin 1-4. The isolation of multipotent adult dermal precursors was first reported by Miller F. D laboratory 5, 6. These early studies described a multipotent precursor cell population from adult mammalian dermis 5. These cells--termed SKPs, for skin-derived precursors-- were isolated and expanded from rodent and human skin and differentiated into both neural and mesodermal progeny, including cell types never found in skin, such as neurons 5. Immunocytochemical studies on cultured SKPs revealed that cells expressed vimentin and nestin, an intermediate filament protein expressed in neural and skeletal muscle precursors, in addition to fibronectin and multipotent stem cell markers 6. Until now, the adult stem cells population SKPs have been isolated from freshly collected mammalian skin biopsies.
Recently, we have established and reported that a population of skin derived precursor cells could remain present in primary fibroblast cultures established from skin biopsies 7. The assumption that a few somatic stem cells might reside in primary fibroblast cultures at early population doublings was based upon the following observations: (1) SKPs and primary fibroblast cultures are derived from the dermis, and therefore a small number of SKP cells could remain present in primary dermal fibroblast cultures and (2) primary fibroblast cultures grown from frozen aliquots that have been subjected to unfavorable temperature during storage or transfer contained a small number of cells that remained viable 7. These rare cells were able to expand and could be passaged several times. This observation suggested that a small number of cells with high proliferation potency and resistance to stress were present in human fibroblast cultures 7.
We took advantage of these findings to establish a protocol for rapid isolation of adult stem cells from primary fibroblast cultures that are readily available from tissue banks around the world (Figure 1). This method has important significance as it allows the isolation of precursor cells when skin samples are not accessible while fibroblast cultures may be available from tissue banks, thus, opening new opportunities to dissect the molecular mechanisms underlying rare genetic diseases as well as modeling diseases in a dish.

Na&#239;ve Adult Stem Cells Isolation from Primary Human Fibroblast Cultures

We report a method to isolate na&#239;ve multipotent skin-derived precursor (SKP) cells from primary human fibroblast cultures. We show that these SKPs derived from fibroblast cultures share similar stem cell properties to the ones derived directly from human skin biopsies. These cells express the neural crest marker, nestin, in addition to the multipotent markers such as OCT4 and Nanog.

Over the last decade, several adult stem cell  populations have been identified in human skin 1-4.  The isolation of multipotent adult dermal precursors ...

Isolation, Culture, and Functional Characterization of Adult Mouse Cardiomyoctyes

The use of primary cardiomyocytes (CMs) in culture has provided a powerful complement to murine models of heart disease in advancing our understanding of heart disease. In particular, the ability to study ion homeostasis, ion channel function, cellular excitability and excitation-contraction coupling and their alterations in diseased conditions and by disease-causing mutations have led to significant insights into cardiac diseases. Furthermore, the lack of an adequate immortalized cell line to mimic adult CMs, and the limitations of neonatal CMs (which lack many of the structural and functional biomechanics characteristic of adult CMs) in culture have hampered our understanding of the complex interplay between signaling pathways, ion channels and contractile properties in the adult heart strengthening the importance of studying adult isolated cardiomyocytes. Here, we present methods for the isolation, culture, manipulation of gene expression by adenoviral-expressed proteins, and subsequent functional analysis of cardiomyocytes from the adult mouse. The use of these techniques will help to develop mechanistic insight into signaling pathways that regulate cellular excitability, Ca2+ dynamics and contractility and provide a much more physiologically relevant characterization of cardiovascular disease.

Here we describe the isolation of adult mouse cardiomyoctyes using a Langendorff perfusion system. The resulting cells are Ca2+-tolerant, electrically quiescent and can be cultured and transfected with adeno- or lentiviruses to manipulate gene expression. Their functionality can also be analyzed using the MMSYS system and patch clamp techniques.

The use of primary cardiomyocytes (CMs) in culture has provided a powerful complement to murine models of heart disease in advancing our understanding of ...

Manual Isolation of Adipose-derived Stem Cells from Human Lipoaspirates

In 2001, researchers at the University of California, Los Angeles, described the isolation of a new population of adult stem cells from liposuctioned adipose tissue that they initially termed Processed Lipoaspirate Cells or PLA cells. Since then, these stem cells have been renamed as Adipose-derived Stem Cells or ASCs and have gone on to become one of the most popular adult stem cells populations in the fields of stem cell research and regenerative medicine. Thousands of articles now describe the use of ASCs in a variety of regenerative animal models, including bone regeneration, peripheral nerve repair and cardiovascular engineering. Recent articles have begun to describe the myriad of uses for ASCs in the clinic. The protocol shown in this article outlines the basic procedure for manually and enzymatically isolating ASCs from large amounts of lipoaspirates obtained from cosmetic procedures. This protocol can easily be scaled up or down to accommodate the volume of lipoaspirate and can be adapted to isolate ASCs from fat tissue obtained through abdominoplasties and other similar procedures.

In 2001, researchers at UCLA described the isolation of a population of adult stem cells, termed Adipose-derived Stem Cells or ASCs, from adipose tissue. This article outlines the isolation of ASCs from lipoaspirates using a manual, enzymatic digestion protocol using collagenase.

In 2001, researchers at the University of  California, Los Angeles, described the isolation of a new population of adult  stem cells from liposuctioned ...

Isolation and Culture of Dental Epithelial Stem Cells from the Adult Mouse Incisor

Understanding the cellular and molecular mechanisms that underlie tooth regeneration and renewal has become a topic of great interest1-4, and the mouse incisor provides a model for these processes. This remarkable organ grows continuously throughout the animal&#39;s life and generates all the necessary cell types from active pools of adult stem cells housed in the labial (toward the lip) and lingual (toward the tongue) cervical loop (CL) regions. Only the dental stem cells from the labial CL give rise to ameloblasts that generate enamel, the outer covering of teeth, on the labial surface. This asymmetric enamel formation allows abrasion at the incisor tip, and progenitors and stem cells in the proximal incisor ensure that the dental tissues are constantly replenished. The ability to isolate and grow these progenitor or stem cells in vitro allows their expansion and opens doors to numerous experiments not achievable in vivo, such as high throughput testing of potential stem cell regulatory factors. Here, we describe and demonstrate a reliable and consistent method to culture cells from the labial CL of the mouse incisor.

The continuously growing mouse incisor provides a model for studying renewal of dental tissues from dental epithelial stem cells (DESCs). A robust system for consistently and reliably obtaining these cells from the incisor and expanding them in vitro is reported here.

Understanding the cellular and molecular mechanisms that underlie tooth regeneration and renewal has become a topic of great interest1-4, and the mouse ...

Isolation and Characterization of Adult Cardiac Fibroblasts and Myofibroblasts

Cardiac fibrosis in response to injury is a physiological response to wound healing. Efforts have been made to study and target fibroblast subtypes that mitigate fibrosis. However, fibroblast research has been hindered due to the lack of universally acceptable fibroblast markers to identify quiescent as well as activated fibroblasts. Fibroblasts are a heterogenous cell population, making them difficult to isolate and characterize. The presented protocol describes three different methods to enrich fibroblasts and myofibroblasts from uninjured and injured mouse hearts. Using a standard and reliable protocol to isolate fibroblasts will enable the study of their roles in homeostasis as well as fibrosis modulation.

Obtaining a pure population of fibroblasts is crucial to studying their role in wound repair and fibrosis. Described here is a detailed method to isolate fibroblasts and myofibroblasts from uninjured and injured mouse hearts followed by characterization of their purity and functionality by immunofluorescence, RTPCR, fluorescence-assisted cell sorting, and collagen gel contraction.

Cardiac fibrosis in response to injury is a physiological response to wound healing. Efforts have been made to study and target fibroblast subtypes that ...

Isolation, Characterization, and Differentiation of Cardiac Stem Cells from the Adult Mouse Heart

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