This study was supported by National Institutes of Health Research grant R01-DE021683-01 and National Institutes of Health Research grant R01-DE019434 to M.T.L.; Howard Hughes Medical Institute Research Fellowship to M.T.C. D.C.W was supported by the A.C.S Franklin Martin Faculty Research Fellowship, The Hagey Laboratory for Pediatric Regenerative Medicine, and the Stanford University Child Health Research Institute Faculty Scholar Award.

NOTE: All patient samples were obtained with informed consent, and experimental protocols were reviewed and approved by Stanford University Institutional Review Board (Protocol #2188 and #9999).
1. Cell Isolation and Culture:
<ol>
	<li>Obtain human subcutaneous adipose tissue from healthy female patients undergoing elective lipoaspiration of the abdomen, flank, and/or thigh region under local/general anesthesia. Ensure that Institutional Review Board (IRB) approval has been obtained for the protocol of isolating ASCs from human tissues, and follow institutional safety precautions while working with such materials.</li>
	<li>To obtain the SVF from the lipoaspirated adipose tissue, first wash the lipoaspirate three times with equal volumes of 1x sterile phosphate-buffered saline (PBS). Carefully aspirate and discard the bottom aqueous layer.</li>
	<li>Prepare the collagenase digestion buffer: 0.075% Type I collagenase in Hank&#8217;s Balanced Salt Solution (HBSS). Prepare FACS buffer: 2% FBS, 1% P188 and 1% Pen-Strep in PBS. Filter both solutions using a commercially available 0.22 &#956;m pore size fast flow polyethersulfone filter.</li>
	<li>To digest the washed adipose tissue, add an equal volume of collagenase digestion buffer and place digestion vessel securely in a shaking water bath for 60 min at 37 &#176;C (approximately 180 shakes/min). 
	NOTE: It is best to use a larger volume digestion vessel than required, as this allows for maximal digestion during shaking (i.e., 250 ml of collagenase digestion buffer, 250 ml of washed adipose tissue in a 1L sterile flask).</li>
	<li>Neutralize enzymatic activity by adding an equal volume of FACS buffer and allowing to sit at RT for 5 min. Next, centrifuge at 233 x g for 20 min at 4 &#176;C.</li>
	<li>Carefully aspirate and discard the supernatant, taking care not to disturb the high-density SVF pellet.</li>
	<li>Resuspend the pellet in 5-10 ml of RT red cell lysis buffer, based on pellet size. Leave solution to sit at RT for 5 min&#160;and centrifuge at 233 x g for 5 min at RT.</li>
	<li>Aspirate supernatant and resuspend the pellet by adding 5-10 ml of traditional growth media, based on pellet size (Dulbecco&#39;s Modified Eagle Medium [DMEM]/10% FBS/1% penicillin-streptomycin solution [pen-strep]).</li>
	<li>Filter the suspension through a 100 &#956;m nylon cell strainer to remove cellular debris.</li>
	<li>Centrifuge at 233 x g for 5 min at 4 &#176;C, and discard the supernatant without disrupting the pellet.</li>
	<li>Resuspend the pellet in 5-10 ml of traditional growth media, based on pellet size.</li>
	<li>Place 2 x 106 cells in a 15 cm standard culture dish and establish primary cultures O/N at 37 &#176;C/21% O2, 5% CO2. Maintain at sub-confluent levels to prevent spontaneous differentiation at 37 &#176;C/21% O2, 5% CO2 in growth media. 
	NOTE: Cell density in a fully confluent 15 cm plate is approximately 4-6 x 106 cells.</li>
</ol>
2. Staining
<ol>
	<li>Culture ASCs in traditional growth medium at 37 &#176;C/21% O2, 5% CO2, for 36 hr before staining/sorting.</li>
	<li>Lift ASCs from culture plates using Accutase (as per manufacturer&#8217;s protocol).</li>
	<li>Wash cells once with FACS buffer (PBS with 2% FBS and 1% pen-strep).</li>
	<li>Centrifuge at 233 x g for 5 min at 4 &#176;C.</li>
	<li>Discard the supernatant without disrupting the pellet. Resuspend the cells in 0.5-1 ml of FACS buffer (depending on cell number and amount of antibody desired). 
	NOTE: The volume of the cell suspension, in accordance with the FACS antibody manufacturer&#8217;s recommendations, determines antibody concentration. However, titration of antibody concentration, using a starting concentration of 1:100, is usually advised if it is the first time to use an antibody.</li>
	<li>Count the total number of cells using a hemocytometer.</li>
	<li>Reserve 100 ul aliquots in 1.5 ml centrifuge tubes to be used for an unstained sample and single-color controls (according to the number of fluorescent antibodies used).</li>
	<li>Add the appropriate fluorescently-labeled monoclonal antibodies (at predetermined concentrations, per manufacturer&#8217;s instructions) and incubate for 20-30 min on ice, shielded from light.
	<ol>
		<li>To label osteogenic subpopulation: Dilute anti-CD90 (APC anti-human CD90 (Thy1)) or anti-CD105 (FITC anti-human CD105 (endoglin)) in FACS buffer to a concentration of 1:50.</li>
		<li>To label other cell populations (e.g., hematopoietic and endothelial cells): Dilute anti-CD45 (Anti-Human CD45 Pacific Blue), anti-CD34 (Anti-Human CD34 APC), and/or anti-CD31 (Anti-Human CD31 PE) in FACS buffer to a concentration of 1:50.</li>
		<li>If not using directly conjugated antibodies, use a biotinylated primary antibody with an appropriate streptavidin-conjugated secondary antibody, such as Streptavidin PE-Cy7, at a dilution of 1:100.</li>
	</ol>
	</li>
	<li>After incubation, wash the cells twice: fill tubes with FACS buffer and centrifuge at 233 x g for 5 min at 4 &#176;C, aspirating supernatant.</li>
	<li>Resuspend the cells in 400-500 &#956;l&#160;FACS buffer and filter samples through a 70 &#956;m nylon cell strainer to remove cell clumps.</li>
	<li>Transfer labeled cells into FACS tubes with filter top and keep samples on ice for the duration of analysis.</li>
</ol>
3. Fluorescence-activated Cell Sorting
NOTE: The following steps mandate previous knowledge in fluorescence-activated cell sorting (FACS) or the assistance of a skilled technician.
<ol>
	<li>Using the appropriate FACS software, design analysis plots to examine forward scatter (FSC), side scatter (SSC), Phycoerythrin (PE)-Texas Red, Pacific Blue, Fluorescein Isothiocyanate (FITC), Allophycocyanin (APC) and any other fluorophore used to label cells.</li>
	<li>Prior to loading into the cell sorter, briefly vortex each sample to resuspend the cells.</li>
	<li>Commence with analysis of the unstained sample in order to set gates for the total cell population, to exclude cellular debris, and to determine baseline autofluorescence.</li>
	<li>Add propidium iodide (PI) to the unstained sample and analyze it in order to visualize the population of live cells within the total cell population. Construct a gate around this population.</li>
	<li>Analyze a single-color control sample for each fluorochrome in order to set fluorescence compensation.</li>
	<li>Analyze the stained sample to set the position of gates for sorting.</li>
	<li>Add PI to the stained sample in order to stain dead cells.</li>
	<li>Sort the labeled cell populations. Sort into either 1.5 ml centrifuge tubes or conical tubes (15 ml) containing culture medium.</li>
	<li>Manually cease sorting once the required quantity of cells has been obtained.</li>
	<li>Using FACS, perform a purity check by analyzing a small fraction (e.g., 500 cells) of the acquired cell population. 
	NOTE: This step confirms the purity of the sorted cell populations. Ideally, purity should be greater than 90-95%.</li>
	<li>Centrifuge cells at 233 x g for 5 min at 4 &#176;C immediately following completion of sorting and resuspend in 1 ml of fresh medium containing 10% FBS. 
	NOTE: The amount of media used may be increased based on the size of the cell pellet.</li>
	<li>Plate on gelatin-coated plates to improve cell viability. Depending on final cell yield, plate 300,000 cells per well in a 6-well plate, 100,000 cells per well in a 12-well plate.</li>
</ol>

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None of the authors have a financial interest in any of the products, devices, or drugs mentioned in this manuscript. None of the authors have any competing financial interest to report.

Currently, the isolation of homogenous subpopulations of ASCs from the SVF of human adipose tissue remains a challenging though desirable goal. Isolation of pro-osteogenic ASC subpopulations is particularly desirable, as such cells can be used to study the formation and homeostasis of skeletal tissues. However, the SVF of adipose tissue harbors significant heterogeneity with regard to stem cell capacity and differentiation potential.11 The molecular basis for this heterogeneity cannot be understood from pooled...

The heterogeneous nature of stem cell populations is not yet fully understood and remains a major impediment to the development of clinically effective stem cell-based therapeutic applications. One of the most common ways to characterize a heterogeneous population of stem cells is to employ a cell sorting method, such as fluorescence-activated cell sorting (FACS), to separate cells based on their surface marker expression profiles. As sorting methods become more complex, it becomes possible to identify more distinct functional subpopulations of cells. Microfluidic-based technologies are becoming more and more frequently utilized in analysis of gene expression at the single cell level. Multiplexed quantitative polymerase chain reaction (qPCR) within a microfluidic chip allows for effective and reliable high-resolution, single cell transcriptional analysis.1-5
In a previous study using single cell transcriptional profiling of 48 genes, considerable transcriptional heterogeneity was observed among ASCs.6 However, the distribution of genes MSX2, BMP-5, BMP-7, ALP, OCN, RUNX2 exhibited a strong association with a cluster of cells possessing highly osteogenic transcriptional profiles. To isolate cells according to this osteogenic gene expression profile, surface antigen expression patterns were correlated with transcription patterns and surface marker expression of endoglin (CD105) was subsequently discovered to closely correlate with enhanced osteogenic differentiation potential of ASCs. Independent of CD105 expression, expression of surface receptor Thy-1 (CD90), a glycosyl-phosphatidylinositol-linked membrane protein previously shown by Chen et al. to be associated with osteoprogenitor cells, was also correlated with osteogenic gene expression.6,7 These findings provide the opportunity to prospectively isolate subpopulations within the larger heterogeneous pool of ASCs with increased osteogenic capacity for cell-based bone tissue engineering applications.

<table border="0" cellpadding="0" cellspacing="0" width="618">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:275px;">Name of Reagent/Material</td>
			<td style="width:152px;">Company</td>
			<td style="width:112px;">Catalog Number</td>
			<td style="width:79px;">Comments</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:275px;">Disposable 250 mL Conical Tubes</td>
			<td style="width:152px;">Corning (Thomas Scientific)</td>
			<td style="width:112px;">2602A43</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:275px;">Penicillin-Streptomycin (10,000 U/mL)</td>
			<td style="width:152px;">Gibco</td>
			<td style="width:112px;">15140-122</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:275px;">DMEM, high glucose, GlutaMAX Supplement</td>
			<td style="width:152px;">Gibco</td>
			<td style="width:112px;">10566-016</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PBS, pH 7.4</td>
			<td style="width:152px;">Gibco</td>
			<td>10010-023</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Betadine - Antiseptic Povidone/Iodine Solution</td>
			<td style="width:152px;">Purdue&#160;</td>
			<td>PFC-67618015017</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hank&#39;s Balanced Salt Solution, 1X</td>
			<td style="width:152px;">Cellgro</td>
			<td>21-023-CV</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fetal Bovine Serum, Certified, US Origin</td>
			<td style="width:152px;">Gibco</td>
			<td>16000-044</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Collagenase from&#160;Clostridium histolyticum</td>
			<td style="width:152px;">Sigma-Aldrich</td>
			<td>C0130-5G</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">ACCUTASE Cell Detachment Solution</td>
			<td style="width:152px;">Stem Cell Technologies</td>
			<td>7920</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:275px;">APC Mouse Anti-Human CD90</td>
			<td style="width:152px;">BD Pharmingen</td>
			<td style="width:112px;">559869</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:275px;">FITC Mouse anti-Human CD105 (Endoglin)</td>
			<td style="width:152px;">BD Pharmingen</td>
			<td style="width:112px;">561443</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:275px;">Anti-Human CD45 eFluor 450 (Pacific Blue replacement)&#160;</td>
			<td style="width:152px;">eBioscience</td>
			<td style="width:112px;">48-9459-41</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:275px;">Anti-Human CD34 APC</td>
			<td style="width:152px;">eBioscience</td>
			<td style="width:112px;">17-0349-41</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:275px;">Anti-Human CD31 (PECAM-1) PE</td>
			<td style="width:152px;">eBioscience</td>
			<td style="width:112px;">12-0319-41</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:275px;">Streptavidin PE-Cyanine7</td>
			<td style="width:152px;">eBioscience</td>
			<td style="width:112px;">25-4317-82</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:275px;">BD FACS Aria II instrument</td>
			<td style="width:152px;">BD Biosciences</td>
			<td style="width:112px;"></td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:275px;">BD FACSDiva Software</td>
			<td style="width:152px;">BD Biosciences</td>
			<td style="width:112px;"></td>
			<td style="width:79px;"></td>
		</tr>
	</tbody>
</table>

isolation and enrichment of human adipose-derived stromal cells for enhanced osteogenesis

Bone marrow-derived mesenchymal stromal cells (BM-MSCs) are considered the gold standard for stem cell-based tissue engineering applications. However, the process by which they must be harvested can be associated with significant donor site morbidity. In contrast, adipose-derived stromal cells (ASCs) are more readily abundant and more easily harvested, making them an appealing alternative to BM-MSCs. Like BM-MSCs, ASCs can differentiate into osteogenic lineage cells and can be used in tissue engineering applications, such as seeding onto scaffolds for use in craniofacial skeletal defects. ASCs are obtained from the stromal vascular fraction (SVF) of digested adipose tissue, which is a heterogeneous mixture of ASCs, vascular endothelial and mural cells, smooth muscle cells, pericytes, fibroblasts, and circulating cells. Flow cytometric analysis has shown that the surface marker profile for ASCs is similar to that for BM-MSCs. Despite several published reports establishing markers for the ASC phenotype, there is still a lack of consensus over profiles identifying osteoprogenitor cells in this heterogeneous population. This protocol describes how to isolate and use a subpopulation of ASCs with enhanced osteogenic capacity to repair critical-sized calvarial defects.

Using CD90 as a marker for cells with enhanced osteogenesis results in isolation of a highly-enriched populations of human ASCs (Figure 1A, 1B). ASCs were stained with Pacific Blue-conjugated anti-human CD45, FITC-conjugated anti-human CD105, and APC-conjugated anti-human CD90. After sorting, the level of purity was greater than 98%, as quantified by post-sort analysis.
Defining groups of cells based on transcriptional profiles allowed for prospective isolation of two novel su...

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Isolation and Enrichment of Human Adipose-derived Stromal Cells for Enhanced Osteogenesis

The transcriptional heterogeneity within human adipose-derived stromal cells can be defined on the single cell level using cell surface markers and osteogenic genes. We describe a protocol utilizing flow cytometry for the isolation of cell subpopulations with increased osteogenic potential, which may be used to enhance craniofacial skeletal reconstruction.

Bone marrow-derived mesenchymal stromal cells (BM-MSCs) are considered the gold standard for stem cell-based tissue engineering applications. However, the ...

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11.4K Views.  Stanford University School of Medicine. The transcriptional heterogeneity within human adipose-derived stromal cells can be defined on the single cell level using cell surface markers and osteogenic genes. We describe a protocol utilizing flow cytometry for the isolation of cell subpopulations with increased osteogenic potential, which may be used to enhance craniofacial skeletal reconstruction.

Video: Isolation and Enrichment of Human Adipose-derived Stromal Cells for Enhanced Osteogenesis

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

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

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

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

Immunomagnetic Separation of Fat Depot-specific Sca1high Adipose-derived Stem Cells (ASCs)

The isolation of adipose-derived stem cells (ASCs) is an important method in the field of adipose tissue biology, adipogenesis, and extracellular matrix (ECM) remodeling. In vivo, ECM-rich environment consisting of fibrillar collagens provides a structural support to adipose tissues during the progression and regression of obesity. Physiological ECM remodeling mediated by matrix metalloproteinases (MMPs) plays a major role in regulating adipose tissue size and function1,2. The loss of physiological collagenolytic ECM remodeling may lead to excessive collagen accumulation (tissue fibrosis), macrophage infiltration, and ultimately, a loss of metabolic homeostasis including insulin resistance3,4. When a phenotypic change of the adipose tissue is observed in gene-targeted mouse models, isolating primary ASCs from fat depots for in vitro studies is an effective approach to define the role of the specific gene in regulating the function of ASCs. In the following, we define an immunomagnetic separation of Sca1high ASCs.

Immunomagnetic Separation of Fat Depot-specific Sca1high Adipose-derived Stem Cells ASCs

We present the techniques required to isolate the stromal vascular fraction (SVF) from mouse inguinal (subcutaneous) and perigonadal (visceral) adipose tissue depots to assess their gene expression and collagenolytic activity. This method includes the enrichment of Sca1high adipose-derived stem cells (ASCs) using immunomagnetic cell separation.

The isolation of adipose-derived stem cells (ASCs) is an important method in the field of adipose tissue biology, adipogenesis, and extracellular matrix ...

Isolation and Expansion of Mesenchymal Stem/Stromal Cells Derived from Human Placenta Tissue

Mesenchymal stem/stromal cells (MSC) are promising candidates for use in cell-based therapies. In most cases, therapeutic response appears to be cell-dose dependent. Human term placenta is rich in MSC and is a physically large tissue that is generally discarded following birth. Placenta is an ideal starting material for the large-scale manufacture of multiple cell doses of allogeneic MSC. The placenta is a fetomaternal organ from which either fetal or maternal tissue can be isolated. This article describes the placental anatomy and procedure to dissect apart the decidua (maternal), chorionic villi (fetal), and chorionic plate (fetal) tissue. The protocol then outlines how to isolate MSC from each dissected tissue region, and provides representative analysis of expanded MSC derived from the respective tissue types. These methods are intended for pre-clinical MSC isolation, but have also been adapted for clinical manufacture of placental MSC for human therapeutic use.

Herein we describe methods for the dissection of fetal and maternal tissues from human term placenta, followed by isolation and expansion of mesenchymal stem/stromal cells (MSC) from these tissues.

Mesenchymal stem/stromal cells (MSC) are promising candidates for use in cell-based therapies. In most cases, therapeutic response appears to be cell-dose ...

Chondrogenic Differentiation Induction of Adipose-derived Stem Cells by Centrifugal Gravity

Impaired cartilage cannot heal naturally. Currently, the most advanced therapy for defects in cartilage is the transplantation of chondrocytes differentiated from stem cells using cytokines. Unfortunately, cytokine-induced chondrogenic differentiation is costly, time-consuming, and associated with a high risk of contamination during in vitro differentiation. However, biomechanical stimuli also serve as crucial regulatory factors for chondrogenesis. For example, mechanical stress can induce chondrogenic differentiation of stem cells, suggesting a potential therapeutic approach for the repair of impaired cartilage. In this study, we demonstrated that centrifugal gravity (CG, 2,400 &#215; g), a mechanical stress easily applied by centrifugation, induced the upregulation of sex determining region Y (SRY)-box 9 (SOX9) in adipose-derived stem cells (ASCs), causing them to express chondrogenic phenotypes. The centrifuged ASCs expressed higher levels of chondrogenic differentiation markers, such as aggrecan (ACAN), collagen type 2 alpha 1 (COL2A1), and collagen type 1 (COL1), but lower levels of collagen type 10 (COL10), a marker of hypertrophic chondrocytes. In addition, chondrogenic aggregate formation, a prerequisite for chondrogenesis, was observed in centrifuged ASCs.

Mechanical stress can induce the chondrogenic differentiation of stem cells, providing a potential therapeutic approach for the repair of impaired cartilage. We present a protocol to induce the chondrogenic differentiation of adipose-derived stem cells (ASCs) using centrifugal gravity (CG). CG-induced upregulation of SOX9 results in the development of chondrogenic phenotypes.

Impaired cartilage cannot heal naturally. Currently, the most advanced therapy for defects in cartilage is the transplantation of chondrocytes ...

Rapid Isolation of BMPR-IB+ Adipose-Derived Stromal Cells for Use in a Calvarial Defect Healing Model

Invasive cancers, major injuries, and infection can cause bone defects that are too large to be reconstructed with preexisting bone from the patient's own body. The ability to grow bone de novo using a patient's own cells would allow bony defects to be filled with adequate tissue without the morbidity of harvesting native bone. There is interest in the use of adipose-derived stromal cells (ASCs) as a source for tissue engineering because these are obtained from an abundant source: the patient's own adipose tissue. However, ASCs are a heterogeneous population and some subpopulations may be more effective in this application than others. Isolation of the most osteogenic population of ASCs could improve the efficiency and effectiveness of a bone engineering process. In this protocol, ASCs are obtained from subcutaneous fat tissue from a human donor. The subpopulation of ASCs expressing the marker BMPR-IB is isolated using FACS. These cells are then applied to an in vivo calvarial defect healing assay and are found to have improved osteogenic regenerative potential compared with unsorted cells.

Adipose-derived stromal cells may be useful for engineering new tissue from a patient's own cells. We present a protocol for the isolation of a subpopulation of human adipose-derived stromal cells (ASCs) with increased osteogenic potential, followed by application of the cells in an in vivo calvarial healing assay.

Invasive cancers, major injuries, and infection can cause bone defects that are too large to be reconstructed with preexisting bone from the patient's own ...

Isolation of Mouse Endometrial Epithelial and Stromal Cells for In Vitro Decidualization

Decidualization is a progesterone-dependent differentiation process of endometrial stromal cells and is a prerequisite for successful embryo implantation. Although many efforts have been made to reveal the underlying mechanisms of decidualization, the exact signaling between the epithelial cells that are in contact with the embryo and the underlying stromal cells remains poorly understood. Therefore, studying decidualization in a way that takes both the epithelial and stromal cells into account could improve our knowledge about the molecular details of decidualization. For this purpose, in vivo models of artificial decidualization are physiologically the most relevant; however, manipulation of intercellular communication is limited. Currently, in vitro cultures of endometrial stromal cells are being used to investigate the modulation of decidualization by several signaling molecules. Conventionally, human or mouse endometrial stromal cells are used. However, the availability of human samples is very often limited. Furthermore, the use of murine tissues is accompanied with variety in the method of culturing. This study presents a validated and standardized method to obtain pure Endometrial Epithelial Cell (EEC) and Stromal Cell (ESC) cultures using adult intact mice treated with estrogen for three consecutive days. The protocol is optimized to improve the yield, viability, and purity of the cells and was further extended in order to study decidualization in a coculture of EEC and ESC. This model may be suitable to exploit the importance of both cell types in decidualization and to evaluate the contribution of significant signaling molecules secreted by EEC or ESC during the intercellular communication.

Isolation of Mouse Endometrial Epithelial and Stromal Cells for In Vitro Decidualization

This study presents a standardized and validated method for the isolation and culture of primary mouse endometrial stromal and epithelial cells, which can be used in a coculture system to study in vitro decidualization.

Decidualization is a progesterone-dependent differentiation process of endometrial stromal cells and is a prerequisite for successful embryo implantation. ...

Isolation and Characterization of Mesenchymal Stromal Cells from Human Umbilical Cord and Fetal Placenta

The human umbilical cord (UC) and placenta are non-invasive, primitive and abundant sources of mesenchymal stromal cells (MSCs) that have increasingly gained attention because they do not pose any ethical or moral concerns. Current methods to isolate MSCs from UC yield low amounts of cells with variable proliferation potentials. Since UC is an anatomically-complex organ, differences in MSC properties may be due to the differences in the anatomical regions of their isolation. In this study, we first dissected the cord/placenta samples into three discrete anatomical regions: UC, cord-placenta junction (CPJ), and fetal placenta (FP). Second, two distinct zones, cord lining (CL) and Wharton&#39;s jelly (WJ), were separated. The explant culture technique was then used to isolate cells from the four sources. The time required for the primary culture of cells from the explants varied depending on the source of the tissue. Outgrowth of the cells occurred within 3 - 4 days of the CPJ explants, whereas growth was observed after 7 - 10 days and 11 - 14 days from CL/WJ and FP explants, respectively. The isolated cells were adherent to plastic and displayed fibroblastoid morphology and surface markers, such as CD29, CD44, CD73, CD90, and CD105, similarly to bone marrow (BM)-derived MSCs. However, the colony-forming efficiency of the cells varied, with CPJ-MSCs and WJ-MSCs showing higher efficiency than BM-MSCs. MSCs from all four sources differentiated into adipogenic, chondrogenic, and osteogenic lineages, indicating that they were multipotent. CPJ-MSCs differentiated more efficiently in comparison to other MSC sources. These results suggest that the CPJ is the most potent anatomical region and yields a higher number of cells, with greater proliferation and self-renewal capacities in vitro. In conclusion, the comparative analysis of the MSCs from the four sources indicated that CPJ is a more promising source of MSCs for cell therapy, regenerative medicine, and tissue engineering.

Here, we present a protocol for the dissection of human umbilical cord (UC) and fetal placenta sample into cord lining (CL), Wharton&#39;s jelly (WJ), cord-placenta junction (CPJ), and fetal placenta (FP) for the isolation and characterization of mesenchymal stromal cells (MSCs) using the explant culture technique.

The human umbilical cord (UC) and placenta are non-invasive, primitive and abundant sources of mesenchymal stromal cells (MSCs) that have increasingly ...

Isolation and Enrichment of Liver Progenitor Subsets Identified by a Novel Surface Marker Combination

During chronic liver injuries, progenitor cells expand in a process called ductular reaction, which also entails the appearance of inflammatory cellular infiltrate and epithelial cell activation. The progenitor cell population during such inflammatory reactions has mostly been investigated using single surface markers, either by histological analysis or by flow cytometry-based techniques. However, novel surface markers identified various functionally distinct subsets within the liver progenitor/stem cell compartment. The method presented here describes the isolation and detailed flow cytometry analysis of progenitor subsets using novel surface marker combinations. Moreover, it demonstrates how the various progenitor cell subsets can be isolated with high purity using automated magnetic and FACS sorting-based methods. Importantly, novel and simplified enzymatic dissociation of the liver allows for the isolation of these rare cell populations with a high viability that is superior in comparison to other existing methods. This is especially relevant for further studying progenitor cells in vitro or for isolating high-quality RNA to analyze the gene expression profile.

Liver injuries are accompanied by progenitor cell expansion that represents a heterogeneous cell population. Novel classification of this cellular compartment allows for the distinguishing of multiple subsets. The method described here illustrates the flow cytometry analysis and high purity isolation of various subsets that can be used for further assays.

During chronic liver injuries, progenitor cells expand in a process called ductular reaction, which also entails the appearance of inflammatory cellular ...

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

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

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

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

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 ...