The authors want to thank Dr. Ivo Kalajzic for the &#945;SMA-GFP mice. Research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institutes of Health (NIH) under Award Number R01GM118300 (S.S.), National Institute of Biomedical Imaging and Bioengineering of the NIH under Award Number R21EB019509 (P.P.Y.), and Scientist Development Grant of the American Heart Association under Award Number 17SDG33630187 (S.S.). Flow cytometry analyses were performed at the VUMC Flow Cytometry Shared Resource which is supported by the Vanderbilt Ingram Cancer Center (P30 CA68485) and the Vanderbilt Digestive Disease Research Center (DK058404).

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	<li>Ivey, M. J., Tallquist, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Defining+the+Cardiac+Fibroblast.">Defining the Cardiac Fibroblast.</a> Circulation Journal. 80 (11), 2269-2276 (2016).</li><li>Prabhu, S. D., Frangogiannis, N. 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G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fibroblasts+in+myocardial+infarction:+a+role+in+inflammation+and+repair.">Fibroblasts in myocardial infarction: a role in inflammation and repair.</a> Journal of Molecular and Cellular Cardiology. 70, 74-82 (2014).</li><li>Saraswati, S., Marrow, S. M. W., Watch, L. A., Young, P. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+a+pro-angiogenic+functional+role+for+FSP1-positive+fibroblast+subtype+in+wound+healing.">Identification of a pro-angiogenic functional role for FSP1-positive fibroblast subtype in wound healing.</a> Nature Communications. 10 (1), 3027 (2019).</li><li>Kong, P., Christia, P., Saxena, A., Su, Y., Frangogiannis, N. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lack+of+specificity+of+fibroblast-specific+protein+1+in+cardiac+remodeling+and+fibrosis.">Lack of specificity of fibroblast-specific protein 1 in cardiac remodeling and fibrosis.</a> American Journal of Physiology -Heart and Circulatory Physiology. 305 (9), 1363-1372 (2013).</li><li>Furtado, M. B., Nim, H. T., Boyd, S. E., Rosenthal, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=View+from+the+heart:+cardiac+fibroblasts+in+development,+scarring+and+regeneration.">View from the heart: cardiac fibroblasts in development, scarring and regeneration.</a> Development. 143 (3), 387-397 (2016).</li><li>Stellato, M., Czepiel, M., Distler, O., Blyszczuk, P., Kania, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+and+Isolation+of+Cardiac+Fibroblasts+From+the+Adult+Mouse+Heart+Using+Two-Color+Flow+Cytometry.">Identification and Isolation of Cardiac Fibroblasts From the Adult Mouse Heart Using Two-Color Flow Cytometry.</a> Frontiers in Cardiovascular Medicine. 6, 105 (2019).</li><li>Ackers-Johnson, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Simplified,+Langendorff-Free+Method+for+Concomitant+Isolation+of+Viable+Cardiac+Myocytes+and+Nonmyocytes+From+the+Adult+Mouse+Heart.">A Simplified, Langendorff-Free Method for Concomitant Isolation of Viable Cardiac Myocytes and Nonmyocytes From the Adult Mouse Heart.</a> Circulatory Research. 119 (8), 909-920 (2016).</li><li>Saraswati, S., Marrow, S. 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T., Eghbali, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+fibrillar+collagen+types+I+and+III+and+basement+membrane+type+IV+collagen+gene+expression+in+pressure+overloaded+rat+myocardium.">Regulation of fibrillar collagen types I and III and basement membrane type IV collagen gene expression in pressure overloaded rat myocardium.</a> Circulatory Research. 67 (4), 787-794 (1990).</li><li>Vasquez, C., Benamer, N., Morley, G. 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The authors have nothing to disclose.

Fibroblasts are a heterogenous group of cells, identified by diverse set of markers. The protein markers that have been used to identify fibroblasts are discoidin domain receptor 2 (DDR2), fibronectin, vimentin, collagen I and III, and Thy115,16,17,18,19,20. Whereas vimentin has been used to identify uninjured quiescent cardi...

Cardiac fibroblasts, cells of mesenchymal origin, play a significant role in maintaining the electrical conduction and mechanical forces in the heart in addition to the maintenance of cardiac architecture during homeostasis1. Following injury, these cells are activated, expand, and produce extracellular matrix (ECM) proteins2. Many preclinical studies have revealed fibroblasts as critical cellular regulators that maintain the structural integrity of an injured heart3 as well as main effector cells responsible for unchecked production and deposition of ECM proteins, resulting in stiff scar formation and heart failure4. Fibroblasts are a heterogenous group of cells, making it challenging to dissect their reparative function from pro-fibrotic maladaptive properties. Recently, the functional heterogeneity of two distinct fibroblast subtypes following myocardial injury have been defined, indicating the possibility of isolating different fibroblast subtypes and studying their role in wound healing5.
Obtaining a pure fibroblast population is crucial in delineating their functional role in repair and fibrosis. However, the presence of multiple fibroblast markers that recognize other cell types make it challenging to isolate a substantially pure fibroblast population6. Several elegant studies have devised clever ways to isolate cardiac fibroblasts from uninjured and injured myocardium. The most popular and well-established method of enriching fibroblasts is through selective adhesion following enzymatic tissue digestion7.
Additionally, fluorescence-activated cell sorting (FACS) of fibroblasts based on cell surface antigens has been successfully described8. In the study, following enzymatic digestion, the mesenchymal cells were sorted as lineage-negative (Lin: Ter119&#8722;CD45&#8722;CD31&#8722;) and gp38-positive (gp38+) from mouse hearts. Gp38+ve cells were confirmed to be fibroblasts based on their co-expression of col1&#945;1 and other mesenchymal markers. Although most tissue digestion is completed after dissecting out the ventricle in a Petri dish, a recent study has investigated the use of a direct needle enzyme perfusion of the left ventricle to isolate myocytes and non-myocytes which include fibroblasts9. Fibroblasts were then isolated by selective adhesion in this case.
This protocol describes the isolation and enrichment of fibroblasts using three methods. The first is an already established method involving selective adhesion of fibroblasts following enzymatic digestion. The second method is used to primarily isolate injury-induced alpha smooth muscle expressing myofibroblasts. The third method involves sequential, magnetic depletion of an enzyme-digested cardiac cell suspension of hematopoietic and endothelial cells. Following depletion, fibroblasts/myofibroblasts are isolated based on the presence of the antigen MEFSK4 using magnetic beads. Recently, MEFSK4 has been described as an antigen present on quiescent as well as activated fibroblasts, making it a suitable marker for fibroblast identification and isolation. Naturally, all the methods described here have unique limitations. It is therefore highly recommended to check the purity of the isolated cell population by flow analysis, immunostaining, and semi-quantitative real-time PCR. However, these methodologies can be expanded upon, and additional markers can be added in order to exclude other contaminating populations prior to utilizing the fibroblast and myofibroblast populations for crucial experiments.

<table><tbody><tr><td>&lt;strong&gt;Reagents&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Acetone</td><td></td><td></td><td></td></tr><tr><td>Anti-fungal (Amphotericin B-solubilized; Fungizone)</td><td>Sigma Aldrich</td><td>A9528</td><td></td></tr><tr><td>Bovine Serium Albumin (BSA)</td><td>Sigma</td><td>9048-46-8</td><td></td></tr><tr><td>Calcium chloride</td><td></td><td></td><td></td></tr><tr><td>Citrate Buffer</td><td></td><td></td><td></td></tr><tr><td>Collagenase blend (Liberase Blendzyme 3 TH)</td><td>Roche Applied Science</td><td></td><td></td></tr><tr><td>DAPI</td><td></td><td></td><td></td></tr><tr><td>DDI water</td><td></td><td></td><td></td></tr><tr><td>DI water</td><td></td><td></td><td></td></tr><tr><td>DMEM-F12 with L-Glutamine and HEPES</td><td>Life technologies</td><td>11330057</td><td></td></tr><tr><td>Dnase I(20U/mL)</td><td>BioRad</td><td>7326828</td><td></td></tr><tr><td>Dulbecco&#039;s Phosphate-Buffered Saline (dPBS) without Ca2+ and Mg2+</td><td>Gibco</td><td>13190-144</td><td></td></tr><tr><td>70% Ethanol</td><td></td><td></td><td></td></tr><tr><td>FC Blocker (Purified anti-mouse CD16/CD32)</td><td>Tonbo Biosciences</td><td>70-0161</td><td></td></tr><tr><td>Fetal Bovine Serum (FBS)</td><td>Life technologies</td><td>16000044</td><td></td></tr><tr><td>10% goat serum</td><td></td><td></td><td></td></tr><tr><td>Hank&#039;s Balanced Salt Solution (HBSS) with Ca2+ and Mg2+</td><td>Corning</td><td>21-023-CV</td><td></td></tr><tr><td>1M HEPES</td><td>Corning</td><td>25-060-Ci</td><td></td></tr><tr><td>Krebs-Henseleit Buffer powder</td><td>Sigma</td><td>K3753</td><td></td></tr><tr><td>Mycoplasma prophylactic (Plasmocin)</td><td>Invivogen</td><td>ant-mpp</td><td></td></tr><tr><td>Penicillin/Streptomycin</td><td>Thermo Fisher Scientific</td><td>15140122</td><td></td></tr><tr><td>1x Phosphate-Buffered Saline (PBS)</td><td></td><td></td><td></td></tr><tr><td>10x Red Blood Cell Lysis Buffer</td><td>Miltenyi</td><td>130-094-183</td><td></td></tr><tr><td>Slow-fade Mounting Media</td><td></td><td></td><td></td></tr><tr><td>Sodium azide</td><td></td><td></td><td></td></tr><tr><td>Sodium bicarbonate</td><td></td><td></td><td></td></tr><tr><td>TGF&amp;beta;</td><td></td><td></td><td></td></tr><tr><td>Trypan Blue Stain (0.4%)</td><td>Gibco</td><td>15250-061</td><td></td></tr><tr><td>Type 1 Rat Collagen</td><td></td><td></td><td></td></tr><tr><td>&lt;strong&gt;Antibodies&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>7AAD (stock: 1 mg/mL solution in DMSO)</td><td>Molecular Probes</td><td>A1310</td><td>dilution = 1:1000; RRID =</td></tr><tr><td>CD45-APC</td><td>BD Bioscience</td><td>559864</td><td>dilution = 1:200; RRID = AB_398672</td></tr><tr><td>CD31-PE</td><td>BD Bioscience</td><td>553373</td><td>dilution = 1:200; RRID = AB_394819</td></tr><tr><td>CD31</td><td>BD Biosciences</td><td>553370</td><td>dilution = 1:250; RRID = AB_394816</td></tr><tr><td>CD45</td><td>BD Biosciences</td><td>553076</td><td>dilution = 1:250; RRID = AB_394606</td></tr><tr><td>COL 1&amp;alpha;1</td><td>MD Bioproducts</td><td>203002</td><td>dilution = 1:1000; RRID =</td></tr><tr><td>Ghost dye violet 510 (Formulation: 1 uL/test in DMSO)</td><td>Tonbo Biosciences</td><td>13-0870</td><td>dilution = 1:1000; RRID =</td></tr><tr><td>Goat anti-mouse Alexa Fluor 488</td><td>Molecular Probes</td><td>A11029</td><td>dilution = 1:200; RRID = AB_138404</td></tr><tr><td>Goat anti-rabbit-Cy3</td><td>Southern Biotech</td><td>4050-02</td><td>dilution = 1:200; RRID = AB_2795952</td></tr><tr><td>Goat anti-rabbit-FITC</td><td>Jackson Immunoresearch Laboratories</td><td>711-165-152</td><td>dilution = 1:200; RRID = AB_2307443</td></tr><tr><td>Goat anti-rat Alexa Fluor 488</td><td>Molecular Probes</td><td>A11006</td><td>dilution = 1:200; RRID = AB_2534074</td></tr><tr><td>Goat anti-rat Alexa Fluor 647</td><td>Thermo-Fisher</td><td>A21247</td><td>dilution = 1:200; RRID = AB_141778</td></tr><tr><td>Periostin</td><td>Santa Cruz</td><td>SC67233</td><td>dilution = 1:100; RRID = AB_2166650</td></tr><tr><td>Vimentin</td><td>Sigma Aldrich</td><td>V2258</td><td>dilution = 1:200; RRID = AB_261856</td></tr><tr><td>&amp;alpha;-smooth muscle actin (&amp;alpha;SMA)</td><td>Sigma Aldrich</td><td>A2547</td><td>dilution = 1:1000; RRID = AB_476701</td></tr><tr><td>Fibroblast specific protein 1 (FSP1)</td><td>Millipore 07-2274</td><td>07-2274</td><td>dilution = 1:100; RRID = AB_10807552</td></tr><tr><td>CD45 Magnetic Beads</td><td>Miltenyi Biotec</td><td>130-052-301</td><td></td></tr><tr><td>CD31 Magnetic Beads</td><td>Miltenyi Biotec</td><td>130-087-418</td><td></td></tr><tr><td>Anti-feeder cells-APC (MEFSK4)</td><td>Miltenyi Biotec</td><td>130-102-900</td><td>dilution = 1:100; RRID = AB_2660619</td></tr><tr><td>anti-APC Beads</td><td>Miltenyi Biotec</td><td>130-090-855</td><td></td></tr><tr><td>Rat IgG-APC</td><td>Miltenyi Biotec</td><td>130-103-034</td><td>dilution = 1:100; RRID = AB_2661598</td></tr><tr><td>Donkey anti-rat Alexa Fluor405</td><td>Abcam</td><td>ab175670</td><td>dilution = 1:100</td></tr><tr><td>anti-AN2/NG2</td><td>Miltenyi Biotec</td><td>130-097-455</td><td>dilution = 1:11; RRID = AB_2651235</td></tr><tr><td>&lt;strong&gt;Other Materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>0.22 &amp;micro;m Filter</td><td>Thermo Scientific</td><td>723-2520</td><td></td></tr><tr><td>10 cm2 Cell Culture Dish</td><td>Corning</td><td>430167</td><td></td></tr><tr><td>10 mL Pipet</td><td>Fisherbrand</td><td>13-678-11E</td><td></td></tr><tr><td>40 &amp;micro;m Cell Strainer</td><td>Fisherbrand</td><td>22363547</td><td></td></tr><tr><td>5 mL Pipet</td><td>Fisherbrand</td><td>13-678-11D</td><td></td></tr><tr><td>50 mL Conical Tube</td><td>Falcon</td><td>352070</td><td></td></tr><tr><td>6-well Plate</td><td>Corning</td><td>3506</td><td></td></tr><tr><td>Flow Cytometry Tubes</td><td>Falcon</td><td>352058</td><td></td></tr><tr><td>Forceps</td><td></td><td></td><td></td></tr><tr><td>Rocker</td><td></td><td></td><td></td></tr><tr><td>Single Edge Blade</td><td>PAL</td><td>62-0177</td><td></td></tr><tr><td>Surgical Scissors</td><td></td><td></td><td></td></tr><tr><td>GFP-&amp;alpha;SMA Reporter Mice</td><td></td><td></td><td></td></tr><tr><td>MACS Separator Magnetic Field</td><td></td><td></td><td></td></tr><tr><td>MACS Separation Column</td><td></td><td></td><td></td></tr><tr><td>Coverslips</td><td></td><td></td><td></td></tr><tr><td>Qaigen Rneasy Mini Kit</td><td>Qaigen</td><td>74104</td><td></td></tr><tr><td>Ambion RNAqueous Micro Total Isolation Kit</td><td>Ambion</td><td>AM1931</td><td></td></tr><tr><td>BioRad iScript cDNA Syntehsis Kit</td><td>BioRad</td><td>1708891</td><td></td></tr><tr><td>48-well Plate</td><td></td><td></td><td></td></tr><tr><td>30G Needle</td><td></td><td></td><td></td></tr><tr><td>3 Laser Flow Cytometry Machine (BD LSRFortessa)</td><td>BD Biosciences</td><td></td><td></td></tr><tr><td>4 Laser Flow Cytometry Machine (BD FACSAria III)</td><td>BD Biosciences</td><td></td><td></td></tr><tr><td>Flow Data Acquiring Software (BD FACSDiva Software v8.0a)</td><td>BD Biosciences</td><td></td><td></td></tr><tr><td>Flow Data Analysis Software (FlowJo Software)</td><td>BD Biosciences</td><td></td><td></td></tr></tbody></table>

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.

Flow gating scheme demonstrating myofibroblast isolation using &#945;SMA-GFP reporter mice 
Uninjured hearts showed no detectable GFP+ cells in &#945;SMA-GFP reporter mouse model; hence, they were used to establish a gate for the background signal of the GFP channel post-compensation (Figure 2). &#945;SMA+ cells were sorted based on the presence of GFP expression from the injured left ventricle 10 days following MI. A small percentage of endothelia...

Watch this Scientific Journal Video about Isolation and Characterization of Adult Cardiac Fibroblasts and Myofibroblasts at JoVE.com

Isolation and Characterization of Adult Cardiac Fibroblasts and Myofibroblasts

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-adult-cardiac-fibroblasts

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JoVE Journal

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15.7K Views.  Vanderbilt University Medical Center. Dit protocol stelt ons in staat om zowel rustige als letsel-geïnduceerde geactiveerde fibroblast populaties met aanzienlijke zuiverheid te isoleren. Het belangrijkste voordeel van deze techniek is de flexibiliteit voor improvisatie. Voor stroom, evenals op kralen gebaseerde isolatie, kan men antilichamen tegen vervuilende cellen bevatten om ze uit te sluiten van de geïsoleerde doelcellen.Deze techniek wordt voornamelijk gebruikt voor cardiale fibroblast isolatie. Echter, het kan word...

Video: Isolation and Characterization of Adult Cardiac Fibroblasts and Myofibroblasts

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

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

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

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

Developmental Biology

Murine Dermal Fibroblast Isolation by FACS

Fibroblasts are the principle cell type responsible for secreting extracellular matrix and are a critical component of many organs and tissues. Fibroblast physiology and pathology underlie a spectrum of clinical entities, including fibroses in multiple organs, hypertrophic scarring following burns, loss of cardiac function following ischemia, and the formation of cancer stroma. However, fibroblasts remain a poorly characterized type of cell, largely due to their inherent heterogeneity. Existing methods for the isolation of fibroblasts require time in cell culture that profoundly influences cell phenotype and behavior. Consequently, many studies investigating fibroblast biology rely upon in vitro manipulation and do not accurately capture fibroblast behavior in vivo. To overcome this problem, we developed a FACS-based protocol for the isolation of fibroblasts from the dorsal skin of adult mice that does not require cell culture, thereby preserving the physiologic transcriptional and proteomic profile of each cell. Our strategy allows for exclusion of non-mesenchymal lineages via a lineage negative gate (Lin-) rather than a positive selection strategy to avoid pre-selection or enrichment of a subpopulation of fibroblasts expressing specific surface markers and be as inclusive as possible across this heterogeneous cell type.

Fibroblast behavior underlies a spectrum of clinical entities, but they remain poorly characterized, largely due to their inherent heterogeneity. Traditional fibroblast research relies upon in vitro manipulation, masking in vivo fibroblast behavior. We describe a FACS-based protocol for the isolation of mouse skin fibroblasts that does not require cell culture.

Fibroblasts are the principle cell type responsible for secreting extracellular matrix and are a critical component of many organs and tissues. Fibroblast ...

Isolation and Characterization of Cardiac Mesenchymal Stromal Cells from Endomyocardial Bioptic Samples of Arrhythmogenic Cardiomyopathy Patients

A normal adult heart is composed of several different cell types, among which cardiac mesenchymal stromal cells represent an abundant population. The isolation of these cells offers the possibility of studying their involvement in cardiac diseases, and, in addition, provides a useful primary cell model to investigate biological mechanisms.
Here, the method for the isolation of C-MSC from arrhythmogenic cardiomyopathy patients&#39; bioptic samples is described. The endomyocardial biopsy sampling is guided in the right ventricular areas adjacent to the scar visualized by electro-anatomical mapping. The digestion of the biopsies in collagenase and their plating on a plastic dish in culture medium to allow C-MSC growth is described. The isolated cells can be expanded in culture for several passages. To confirm their mesenchymal phenotype, the description of immuno-phenotypical characterization is provided. C-MSC are able to differentiate into several cell types like adipocytes, chondrocytes, and osteoblasts: in the context of ACM, characterized by adipocyte deposits in patients&#39; hearts, the protocols for the adipogenic differentiation of C-MSC and the characterization of lipid droplet accumulation are described.

In this article, a method to isolate cardiac mesenchymal stromal cells from endomyocardial bioptic samples of arrhythmogenic cardiomyopathy patients is provided. Their characterization and the protocol to boost their adipogenic differentiation are described.

A normal adult heart is composed of several different cell types, among which cardiac mesenchymal stromal cells represent an abundant population. The ...

Isolation and Genetic Manipulation of Adult Cardiac Myocytes for Confocal Imaging

Cardiac myocytes isolated from adult hearts are widely accepted as a model somewhere half way between embryonic and neonatal muscle cells on one side and a working heart on the other. Thus, cardiomyocytes serve as good models for cardiac cellular physiology and pathophysiology, for pharmaceutical investigations as well as for the exploration of transgenic animal models. Here we describe a method of isolating the cells from the heart. Furthermore we show how a genetic manipulation on cardiac myocytes can be performed without breeding a transgenic animal: This is the combination of long term culture (1 week) and adenoviral gene transfer. The latter one is described from the construction of the virus to the transduction of the cells. It can be used for the expression of genetically encoded biosensors (GEBs), fluorescent fusion proteins, but also for protein over expression and down regulation, e.g. using RNAi. Here we provide an example for the expression of a fusion protein staining a subcellular structure (Golgi). Such protein expression can be visualized by confocal imaging of z-stacks for a 3D-reconstruction of subcellular structures. The protocol comprises state-of-the-art in cell culture, molecular biology and biophysics and thus provides an approach for exploring new horizons in cellular cardiology.

Adult cardiac myocytes are primary cells that can be isolated from animal hearts and cultured for several days. Within this culture period adenoviral gene transfer can be used to express genetically encoded biosensors (GEBs) or fluorescent fusion proteins. Both approaches allow cellular investigations by means of confocal microscopy.

Cardiac myocytes isolated from adult hearts are widely accepted as a model somewhere half way between embryonic and neonatal muscle cells on one side and ...

Isolation and Cultivation of Adult Rat Cardiomyocytes

In an intact heart, adjacent cells influence adult cardiomyocytes. With the method of isolation and cultivation of adult cardiomyocytes, a precise investigation of the behavior of these cells under specific treatments and environments is possible. This manuscript presents a protocol for successful isolation and cultivation of adult rat ventricular cardiomyocytes (ARVC).
The rat is sacrificed by cervical dislocation under deep anesthesia. Then, the heart is extracted and the aorta is uncovered. Subsequently, perfusion on the Langendorff perfusion system with calcium depletion and collagenase treatment is performed. Afterwards, ventricular tissue gets minced, re-circulated, and filtered, followed by three centrifugation steps with gradual addition of CaCl2 until physiological calcium concentration is reached. ARVC are plated on cell culture dishes. After refreshing the cell culture medium, ARVC can be cultivated for up to six days without changing the serum-containing culture medium. Isolation of ARVC is a calcium sensitive process. Small changes in the intracellular calcium concentration cause a decrease in the quality and viability of the isolated cells.
Freshly isolated ARVC are rod shaped. Within the first days of cultivation they lose the rod-shaped morphology and form pseudopodia-like structures (spreading). During this morphological formation ARVC initially degrade their contractile elements followed by a reformation through actin stress fibers and de novo sarcomerogenesis. After one week of cultivation, most ARVC show a widespread appearance with a clearly detectable cross striation. This process is sensitive to intracellular calcium concentration, as treatment with ionomycin attenuates spreading. Key markers in this process of de- and re-differentiation are &#946;-myosin heavy chain (&#946;-MHC), oncostatin M (OSM), and swiprosin-1 (EFHD2). Recent studies have suggested that cardiac re- and de-differentiation occurring under culture conditions mimics features seen in vivo during cardiac remodeling. Therefore, isolation and cultivation of ARVC play a key role in understanding the biology of cardiomyocytes.

Here, we present a protocol for the isolation and cultivation of adult rat ventricular cardiomyocytes (ARVC). Isolated ARVC can be used for short and long-term cultivation. The isolation and cultivation of ARVC can play a key role in developing new treatment regimens for cardiac diseases.

In an intact heart, adjacent cells influence adult cardiomyocytes. With the method of isolation and cultivation of adult cardiomyocytes, a precise ...

Medicine

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 ...

Ultrasonic-augmented Primary Adult Fibroblast Isolation

Primary adult fibroblasts have become an important tool to study fibrosis, fibroblast interactions and inflammation in all body tissues. Since primary fibroblasts cannot divide indefinitely due to myofibroblast differentiation or senescence induction, new cultures must be established regularly. However, there are several obstacles to overcome during the processes of developing a reliable isolation protocol and primary fibroblast isolation itself: the method&#8217;s degree of difficulty (especially for beginners), the risk of bacterial contamination, the required time until primary fibroblasts can be used for experiments, and subsequent cell quality and viability. In this study, a fast, reliable and easy-to-learn protocol to isolate and culture primary adult fibroblasts from mouse heart, lung, liver and kidney combining enzymatic digestion and ultrasonic agitation is provided.

We present a protocol to isolate primary adult fibroblasts in an easy, fast and reliable way, performable by beginners (e.g., students). The procedure combines enzymatic tissue digestion and mechanical agitation with ultrasonic waves to obtain primary fibroblasts. The protocol can easily be adapted to specific experimental requirements (e.g., human tissue).

Primary adult fibroblasts have become an important tool to study fibrosis, fibroblast interactions and inflammation in all body tissues. Since primary ...

Isolation of Myofibroblasts from Mouse and Human Esophagus

Murine and human esophageal myofibroblasts are generated via enzymatic digestion. Neonate (8-12 day old) murine esophagus is harvested, minced, washed, and subjected to enzymatic digestion with collagenase and dispase for 25 min. Human esophageal resection specimens are stripped of muscularis propria and adventitia and the remaining mucosa is minced, and subjected to enzymatic digestion with collagenase and dispase for up to 6 hr. Cultured cells express &#945;-SMA and vimentin and express desmin weakly or not at all. Culture conditions are not conducive to growth of epithelial, hematopoietic, or endothelial cells. Culture purity is further confirmed by flow cytometric evaluation of cell surface marker expression of potential contaminating hematopoietic and endothelial cells. The described technique is straightforward and results in consistent generation of non-hematopoieitc, non-endothelial stromal cells. Limitations of this technique are inherent to the use of primary cultures in molecular biology studies, i.e., the unavoidable variability encountered among cultures established across different mice or humans. Primary cultures however are a more representative reflection of the in vivo state compared to cell lines. These methods also provide investigators the ability to isolate and culture stromal cells from different clinical and experimental conditions, allowing comparisons between groups. Characterized esophageal stromal cells can also be used in functional studies investigating epithelial-stromal interactions in esophageal disorders.

We present a protocol to generate primary cultures of murine and human esophageal stromal cells with a myofibroblast phenotype. Cultured cells have spindle shaped morphology, express &#945;-SMA and vimentin, and lack epithelial, hematopoietic and endothelial cell surface markers. Characterized stromal cells can be used in functional studies of epithelial-stromal interactions.

Murine and human esophageal myofibroblasts are generated via enzymatic digestion. Neonate (8-12 day old) murine esophagus is harvested, minced, washed, ...

Refined CLARITY-Based Tissue Clearing for Three-Dimensional Fibroblast Organization in Healthy and Injured Mouse Hearts

Cardiovascular disease is the most prevalent cause of mortality worldwide and is often marked by heightened cardiac fibrosis that can lead to increased ventricular stiffness with altered cardiac function. This increase in cardiac ventricular fibrosis is due to activation of resident fibroblasts, although how these cells operate within the 3-dimensional (3-D) heart, at baseline or after activation, is not well understood. To examine how fibroblasts contribute to heart disease and their dynamics in the 3-D heart, a refined CLARITY-based tissue clearing and imaging method was developed that shows fluorescently labeled cardiac fibroblasts within the entire mouse heart. Tissue resident fibroblasts were genetically labeled using Rosa26-loxP-eGFP florescent reporter mice crossed with the cardiac fibroblast expressing Tcf21-MerCreMer knock-in line. This technique was used to observe fibroblast localization dynamics throughout the entire adult left ventricle in healthy mice and in fibrotic mouse models of heart disease. Interestingly, in one injury model, unique patterns of cardiac fibroblasts were observed in the injured mouse heart that followed bands of wrapped fibers in the contractile direction. In ischemic injury models, fibroblast death occurred, followed by repopulation from the infarct border zone. Collectively, this refined cardiac tissue clarifying technique and digitized imaging system allows for 3-D visualization of cardiac fibroblasts in the heart without the limitations of antibody penetration failure or previous issues surrounding lost fluorescence due to tissue processing.

A refined method of tissue clearing was developed and applied to the adult mouse heart. This method was designed to clear dense, autofluorescent cardiac tissue, while maintaining labeled fibroblast fluorescence attributed to a genetic reporter strategy.

Cardiovascular disease is the most prevalent cause of mortality worldwide and is often marked by heightened cardiac fibrosis that can lead to increased ...

Simultaneous Isolation of High Quality Cardiomyocytes, Endothelial Cells, and Fibroblasts from an Adult Rat Heart

The rat is an important animal model used in cardiovascular research, and rat cardiac cells are used routinely for in vitro analysis of the molecular mechanisms of cardiovascular disease progression such as cardiac hypertrophy, fibrosis, and atherosclerosis. Although several attempts with variable success have been made to develop immortalized cell lines from the cardiovascular system to understand these cellular mechanisms, primary cells offer a more natural and close to in vivo environment for such studies. Therefore, different laboratories working on a particular cell type have developed protocols to isolate individual types of rat cardiac cells of interest. A protocol that allows the isolation of more than one cell type, however, is missing. Here an optimized protocol is described that allows the isolation of high-quality major cardiac cell types (cardiomyocytes, endothelial cells, and fibroblasts) from a single preparation and enables their use for cellular analyses. This permits the most efficient use of available resources, which may save time and reduce research costs.

Several protocols have been developed and described for the isolation of different cardiac cell types from a rat heart. Here, an optimized protocol is described that allows the isolation of high-quality major cardiac cell types (cardiomyocytes, endothelial cells, and fibroblasts) from a single preparation, reducing the experimental costs.

The rat is an important animal model used in cardiovascular research, and rat cardiac cells are used routinely for in vitro analysis of the molecular ...

Isolation and Characterization of Adult Cardiac Fibroblasts and Myofibroblasts

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