The authors wish to acknowledge and thank those additional research personnel that contributed to the development of the described protocol and its isolation of ASCs, including: Dr. H. Peter Lorenz, MD, Dr. Hiroshi Muzuno, MD, Dr. Jerry Huang, MD, Dr. Adam Katz, MD, Dr. William Futrell, MD, Dr. Rong Zhang, DDS, PhD, Dr. Larissa Rodriguez, MD, Dr. Zeni Alfonso, PhD, and Dr. John Fraser, PhD. The results presented were funded, in part, by research grants from the National Institutes of Health, including the NIAMS and NIDCR Institutes.

<ol>
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E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinct+stem+cells+subpopulations+isolated+from+human+adipose+tissue+exhibit+different+chondrogenic+and+osteogenic+differentiation+potential.">Distinct stem cells subpopulations isolated from human adipose tissue exhibit different chondrogenic and osteogenic differentiation potential.</a> Stem Cell Rev. 7 (1), 64-76 (2011).</li><li>Heydarkhan-Hagvall, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+Adipose+Stem+Cells:+A+Potential+Cell+Source+for+Cardiovascular+Tissue+Engineering.">Human Adipose Stem Cells: A Potential Cell Source for Cardiovascular Tissue Engineering.</a> Cells Tissues Organs. 187 (4), 263-274 (2008).</li><li>Jack, G. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Processed+lipoaspirate+cells+for+tissue+engineering+of+the+lower+urinary+tract:+implications+for+the+treatment+of+stress+urinary+incontinence+and+bladder+reconstruction.">Processed lipoaspirate cells for tissue engineering of the lower urinary tract: implications for the treatment of stress urinary incontinence and bladder reconstruction.</a> J Urol. 174 (5), 2041-2045 (2005).</li><li>Banas, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+hepatic+fate+specification+of+adipose-derived+stem+cells+and+their+therapeutic+potential+for+liver+failure.">Rapid hepatic fate specification of adipose-derived stem cells and their therapeutic potential for liver failure.</a> J Gastroenterol Hepatol. 24 (1), 70-77 (2009).</li><li>Schreml, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Harvesting+human+adipose+tissue-derived+adult+stem+cells:+resection+versus+liposuction.">Harvesting human adipose tissue-derived adult stem cells: resection versus liposuction.</a> Cytotherapy. 11 (7), 947-957 (2009).</li><li>Oedayrajsingh-Varma, M. 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=Adipose+tissue-derived+mesenchymal+stem+cell+yield+and+growth+characteristics+are+affected+by+the+tissue-harvesting+procedure.">Adipose tissue-derived mesenchymal stem cell yield and growth characteristics are affected by the tissue-harvesting procedure.</a> Cytotherapy. 8 (2), 166-177 (2006).</li><li>Ahmad, J., Eaves, F. F., Rohrich, R. J., Kenkel, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+American+Society+for+Aesthetic+Plastic+Surgery+(ASAPS)+survey:+current+trends+in+liposuction.">The American Society for Aesthetic Plastic Surgery (ASAPS) survey: current trends in liposuction.</a> Aesthet Surg J. 31 (2), 214-224 (2011).</li><li>Tierney, E. P., Kouba, D. J., Hanke, C. 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The authors of this manuscript are co-inventors on a patent owned by The Regents of the University of California and licensed to Cytori Therapeutics.

Adipose tissue for the isolation of ASCs can come in many forms: from solid pieces of tissue obtained through resection or lipoplasty to smaller pieces obtained through either syringe extraction or suction-assisted lipoplasty (i.e. liposuction ). Whether more SVF cells (and thereby ASCs) can be obtained from resected or aspirated adipose samples is unclear as conflicting studies have been presented 16, 17. It is possible that either form of adipose tissue is more than suitable for the isolation of SVF...

In 2001, a putative population of multipotent stem cells from adipose tissue was described in the journal Tissue Engineering 1. These cells were given the name Processed Lipoaspirate or PLA cells due to their derivation from processed lipoaspirate tissue obtained through cosmetic surgery. The isolation method described in this article was based on existing enzymatic strategies for the isolation of the stromal vascular fraction (SVF) from adipose tissue 2. The SVF has been defined as a minimally processed population of red blood cells, fibroblasts, endothelial cells, smooth muscle cells, pericytes and pre-adipocytes that have yet to adhere to a tissue culture substrate 2, 3. Culturing of this SVF over time is proposed to eliminate many of these contaminating cell populations and result in an adherent, fibroblastic population. These fibroblasts have been identified in the literature for the last 40 years as being pre-adipocytes. However, our research group demonstrated that these cells possessed mesodermal multipotency and renamed the adherent SVF population as PLA cells. Subsequent studies by numerous other research groups have added to this potential, suggesting both endodermal and ectodermal potentials (for review see 4). Since that time, numerous additional terms for these cells have appeared in the literature. In order to provide some type of consensus, the term Adipose-derived Stem Cells or ASCs was adopted at the 2nd annual IFATS conference. As such, the term ASC will be used in this article. 
The protocol described in this article is a relatively simple procedure that requires standard laboratory equipment and uses simple reagents such as phospho-buffered saline, standard tissue culture media reagents and collagenase. It can produce large numbers of ASCs depending on the amount of starting adipose tissue volume and subsequent culture time. However, the processing of such a large amount of adipose tissue can present some physical issues that can be mitigated to a degree using this protocol. Furthermore, this protocol does require sterile tissue culture facilities and approved biosafety hoods, thereby necessitating the use of an approved tissue culture facility. This requirement can also decrease the utility of the ASC population in clinical applications unless they are isolated in good manufacturing practice (GMP)-approved facilities designed for the isolation and expansion of materials for clinical use. As an alternative, automated systems that can isolate ASCs in a closed system in the operating theatre would avoid this key issue and allow for the immediate use of ASCs without any need for subsequent in vitro expansion. To date, there are six automated systems that are available commercially for the isolation of cells from human tissue. These systems may make it possible to isolate a significant number of ASCs from large amounts of adipose tissue immediately following its harvest. These ASCs could then be reintroduced into the patient for a variety of regenerative purposes without the patient ever having to leave the operating room. In addition to this protocol describing the manual isolation of ASCs, a protocol for automated isolation of ASCs using the Celution System is also given in a companion article.

<table border="1">
	<tbody>
		<tr>
			<td>
				&nbsp;</td>
			<td>
				&nbsp;</td>
			<td>
				&nbsp;</td>
			<td>
				Reagent</td>
		</tr>
		<tr>
			<td>
				DMEM (Dulbecco&#39;s Modification of Eagle&#39;s Medium)</td>
			<td>
				Mediatech Cellgro</td>
			<td>
				10-013-CV</td>
			<td>
				with 4.5 g/ml glucose, L-glutamine, sodium pyruvate</td>
		</tr>
		<tr>
			<td>
				Penicillin/Streptomycin</td>
			<td>
				Mediatech Cellgro</td>
			<td>
				30-002-CI</td>
			<td>
				10,000 IU/ml penicillin/10,000 &mu;g/ml streptomycin</td>
		</tr>
		<tr>
			<td>
				Amphotericin B</td>
			<td>
				Mediatech Cellgro</td>
			<td>
				30-003-CF</td>
			<td>
				250 &mu;g/ml amphotericin B</td>
		</tr>
		<tr>
			<td>
				10X PBS (Phospho-buffered Saline)</td>
			<td>
				Mediatech Cellgro</td>
			<td>
				25-053-CI</td>
			<td>
				without calcium, without magnesium</td>
		</tr>
		<tr>
			<td>
				Trypsin/EDTA</td>
			<td>
				Mediatech Cellgro</td>
			<td>
				20-031-CV</td>
			<td>
				0.25 % trypsin/2.21mM EDTA</td>
		</tr>
		<tr>
			<td>
				Collagenase type IA (from Clostridium histolyticum)</td>
			<td>
				Sigma</td>
			<td>
				C2674</td>
			<td>
				crude preparation; &lt;125 collagen digestion units/mg solid</td>
		</tr>
		<tr>
			<td>
				FBS (Fetal Bovine Serum) heat inactivated</td>
			<td>
				Gemini Bioproducts</td>
			<td>
				100106</td>
			<td>
				USDA source, heat inactivated</td>
		</tr>
		<tr>
			<td>
				10 ml serological pipettes</td>
			<td>
				Genesee Scientific</td>
			<td>
				12-104</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				25 ml serological pipettes</td>
			<td>
				Genesee Scientific</td>
			<td>
				12-106</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				50 ml polypropylene centrifuge tubes</td>
			<td>
				Genesee Scientific</td>
			<td>
				21-106</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				100 mm tissue culture dishes</td>
			<td>
				Genesee Scientific</td>
			<td>
				25-202</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				150 mm tissue culture dishes</td>
			<td>
				Genesee Scientific</td>
			<td>
				25-203</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				500 ml Stericup Filter Units</td>
			<td>
				Millipore</td>
			<td>
				SCGPU05RE</td>
			<td>
				PES membrane, 0.22 &mu;m pore</td>
		</tr>
		<tr>
			<td>
				Cell strainers</td>
			<td>
				FisherBrand</td>
			<td>
				22-363-549</td>
			<td>
				100 &mu;m nylon mesh</td>
		</tr>
		<tr>
			<td>
				dexamethasone - water soluble</td>
			<td>
				Sigma</td>
			<td>
				D-2915</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				L-ascorbic-acid 2 phosphate</td>
			<td>
				Sigma</td>
			<td>
				A-8960</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				&beta;-glycerophosphate disodium salt</td>
			<td>
				Sigma</td>
			<td>
				G-9422</td>
			<td>
				also known as glycerophosphate</td>
		</tr>
		<tr>
			<td>
				insulin</td>
			<td>
				Sigma</td>
			<td>
				I-6634</td>
			<td>
				made from bovine pancreas</td>
		</tr>
		<tr>
			<td>
				indomethacin</td>
			<td>
				Sigma</td>
			<td>
				I-7378</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				apo-transferrin</td>
			<td>
				Sigma</td>
			<td>
				T-4382</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				TGF&beta;1</td>
			<td>
				R&amp;D Systems</td>
			<td>
				240-B-002</td>
			<td>
				recombinant human</td>
		</tr>
		<tr>
			<td>
				Oil Red O</td>
			<td>
				Sigma</td>
			<td>
				O-0625</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				Alcian Blue</td>
			<td>
				Sigma</td>
			<td>
				A-5268</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				Silver nitrate</td>
			<td>
				Sigma</td>
			<td>
				S-0319</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				Hydrochloric acid</td>
			<td>
				Fisher Scientific</td>
			<td>
				A144</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				Paraformaldehyde</td>
			<td>
				Fisher Scientific</td>
			<td>
				30525-89-4</td>
			<td>
				supplied as a 16 % stock</td>
		</tr>
		<tr>
			<td>
				&nbsp;</td>
			<td>
				&nbsp;</td>
			<td>
				&nbsp;</td>
			<td>
				[header]</td>
		</tr>
		<tr>
			<td>
				&nbsp;</td>
			<td>
				&nbsp;</td>
			<td>
				&nbsp;</td>
			<td>
				Equipment Needed</td>
		</tr>
		<tr>
			<td>
				Class II A/B Biosafety hood</td>
			<td>
				Thermo Scientific</td>
			<td>
				&nbsp;</td>
			<td>
				ensure hood has vacuum lines for aspiration</td>
		</tr>
		<tr>
			<td>
				Benchtop centrifuge</td>
			<td>
				Hermle Labnet</td>
			<td>
				Z383</td>
			<td>
				Swing-out rotor for 50 ml tubes required, capable of 1200 x g</td>
		</tr>
		<tr>
			<td>
				Water bath</td>
			<td>
				Fisher Scientific Isotemp</td>
			<td>
				S52602Q</td>
			<td>
				5-10L capacity, capable of 37 C</td>
		</tr>
		<tr>
			<td>
				Automated Pipette Aids</td>
			<td>
				Drummond Pipette Aid XL</td>
			<td>
				4-000-105</td>
			<td>
				&nbsp;</td>
		</tr>
		<tr>
			<td>
				CO2 Incubator</td>
			<td>
				Thermo Scientific</td>
			<td>
				Forma 310</td>
			<td>
				direct heat or water jacketed</td>
		</tr>
	</tbody>
</table>

	&nbsp;

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.

The protocol outline above describes a manual, enzymatic method for the isolation of an SVF from a large volume lipoaspirate sample. Within this SVF are numerous cell populations, including the ASC. Numerous studies propose that culturing this SVF under standard tissue culture conditions will select for an adherent fibroblast population likely to be composed mainly of the ASC type. Consistent with this, we have shown, using flow cytometry and immunofluorescence, that cultured SVF pellets become essentially free of the ...

Watch this Scientific Journal Video about Manual Isolation of Adipose-derived Stem Cells from Human Lipoaspirates at JoVE.com

Manual Isolation of Adipose-derived Stem Cells from Human Lipoaspirates

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 ...

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41.0K Views.  Cytori Therapeutics Inc. 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.

Video: Manual Isolation of Adipose-derived Stem Cells from Human Lipoaspirates

Chromatin Immunoprecipitation from Human Embryonic Stem Cells

The functional and structural complexity of the myriad of cells in metazoan organisms arises from a small number of stem cells. Stem cells are characterized by two fundamental properties: self-renewal and multipotency that allows a stem cell to differentiate into virtually any cell type 1. The progression stem cell to differentiated cell is characterized by loss of multipotency, structural and morphological changes and the hierarchic activity of transcription factors and signaling molecules, whose activities establish and maintain cell-type specific gene expression patterns. At the molecular level, cell differentiation involves dynamic changes of the structure and composition of chromatin and the detection of those dynamic changes can provide valuable insights into the functional features of stem cells and the cell differentiation process 2,3. Chromatin is a highly compacted DNA-protein complex that forms when cells package chromosomal DNA with proteins, mainly histones 4. Stemcellness and cell differentiation has been correlated with the presence of specific arrays of regulatory proteins such as epigenetic factors, histone variants, and transcription factors 2,3,5.
 Chromatin immunoprecipitation (ChIP) provides a valuable method to monitor the presence of RNA, proteins, and protein modifications in chromatin 6,7. The comparison of chromatin from different cell types can elucidate dynamic changes in protein-chromatin associations that occur during cell differentiation.
Chromatin immunoprecipitation involves the purification of in vivo cross-linked chromatin. The isolated chromatin is reduced to smaller fragments by enzymatic digestion or mechanical force. Chromatin fragments are precipitated using specific antibodies to target proteins or protein and DNA modifications. The precipitated DNA or RNA is purified and used as a template for PCR or DNA microarray based assays. Prerequisites for a successful ChIP are high quality antibodies to the desired antigen and the availability of chromatin from control cells that do not express the target molecule. ChIP can correlate the presence of proteins, protein and RNA modifications, and RNA with specific target DNA, and depending on the choice of outread tool, detects the association of target molecules at specific target genes or in the context of an entire genome. The comparison of the distribution of proteins in the chromatin of differentiating cells can elucidate the dynamic changes of chromatin composition that coincide with the progression of cells along a cell lineage.

The differentiation of ESC coincides with cell-type specific changes in the structure and composition of chromatin. The detection of those changes provides valuable insights into the mechanisms that define stemcellness and cell differentiation. Chromatin immunoprecipitation (ChIP) represents a valuable method to dissect the molecular mechanisms underlying stem cell differentiation.

The functional and structural complexity of the myriad of cells in metazoan organisms arises from a small number of stem cells. Stem cells are ...

Isolation of Stem Cells from Human Pancreatic Cancer Xenografts

Cancer stem cells (CSCs) have been identified in a growing number of malignancies and are functionally defined by their ability to undergo self-renewal and produce differentiated progeny1. These properties allow CSCs to recapitulate the original tumor when injected into immunocompromised mice. CSCs within an epithelial malignancy were first described in breast cancer and found to display specific cell surface antigen expression (CD44+CD24low/-)2. Since then, CSCs have been identified in an increasing number of other human malignancies using CD44 and CD24 as well as a number of other surface antigens. Physiologic properties, including aldehyde dehydrogenase (ALDH) activity, have also been used to isolate CSCs from malignant tissues3-5.
Recently, we and others identified CSCs from pancreatic adenocarcinoma based on
ALDH activity and the expression of the cell surface antigens CD44 and CD24, and CD1336-8. These highly tumorigenic populations may or may not be overlapping and display other functions. We found that ALDH+ and CD44+CD24+ pancreatic CSCs are similarly tumorigenic, but ALDH+ cells are relatively more invasive8. In this protocol we describe a method to isolate viable pancreatic CSCs from low-passage human
xenografts9. Xenografted tumors are harvested from mice and made into a single-cell suspension. Tissue debris and dead cells are separated from live cells and then stained using antibodies against CD44 and CD24 and using the ALDEFLUOR reagent,
a fluorescent substrate of ALDH10. CSCs are then isolated by fluorescence activated cell sorting. Isolated CSCs can then be used for analytical or functional assays requiring viable cells.

Cancer stem cells (CSCs) have been identified in a number of malignancies. In this protocol we describe a flow cytometric method utilizing aldehyde dehydrogenase activity and CD44 and CD24 expression to isolate CSCs from human pancreatic adenocarcinoma xenografts. These viable cells can then be used in functional and analytical studies.

Cancer stem cells (CSCs) have been identified in a growing number of malignancies and are functionally defined by their ability to undergo self-renewal ...

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 ...

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&amp;#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 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, Proliferation and Differentiation of Rhesus Macaque Adipose-Derived Stem Cells

Adipose tissue provides a rich and accessible source of multipotent stem cells, which are able to self-renew. These adipose-derived stem cells (ADSCs) provide a consistent ex vivo cellular system that are functionally like that of in vivo adipocytes. Use of ADSCs in biomedical research allows for cellular investigation of adipose tissue metabolic regulation and function. ADSC differentiation is necessary for adequate adipocyte expansion, and suboptimal differentiation is a major mechanism of adipose dysfunction. Understanding changes in ADSC differentiation is crucial to understanding the development of metabolic dysfunction and disease. The protocols described in this manuscript, when followed, will yield mature adipocytes that can be used for several in vitro functional tests to assess ADSC metabolic function, including but not limited to assays measuring glucose uptake, lipolysis, lipogenesis, and secretion. Rhesus macaques (Macaca mulatta) are physiologically, anatomically, and evolutionarily similar to humans and as such, their tissues and cells have been used extensively in biomedical research and for development of treatments. Here, we describe ADSC isolation using fresh subcutaneous and omental adipose tissue obtained from 4&#8211;9-year old rhesus macaques. Adipose tissue samples are enzymatically digested in collagenase followed by filtration and centrifugation to isolate ADSCs from the stromal vascular fraction. Isolated ADSCs are proliferated in stromal media followed by approximately 14&#8211;21 days of differentiation using a cocktail of 0.5 &#956;g/mL dexamethasone, 0.5 mM isobutyl methylxanthine, and 50 &#956;M indomethacin in stromal media. Mature adipocytes are observed at approximately 14 days of differentiation. In this manuscript, we describe protocols for ADSC isolation, proliferation, and differentiation in vitro. Although, we have focused on ADSCs from rhesus macaque adipose tissue, these protocols can be utilized for adipose tissue obtained from other animals with minimal adjustments.

In this article, we describe isolation of rhesus macaque derived adipose-derived stem cells (ADSCs) using an enzymatic tissue digestion protocol. Next, we describe ADSC proliferation which includes cell detachment, counting and plating. Lastly, ADSC differentiation is described using specific adipogenic inducing agents. Additionally, we describe staining techniques to confirm differentiation.

Adipose tissue provides a rich and accessible source of multipotent stem cells, which are able to self-renew. These adipose-derived stem cells (ADSCs) ...

Isolation, Characterization, and Therapeutic Application of Extracellular Vesicles from Cultured Human Mesenchymal Stem Cells

Extracellular vesicles (EVs) are heterogeneous membrane nanoparticles released by most cell types, and they are increasingly recognized as physiological regulators of organismal homeostasis and important indicators of pathologies; in the meantime, their immense potential to establish accessible and controllable disease therapeutics is emerging. Mesenchymal stem cells (MSCs) can release large amounts of EVs in culture, which have shown promise to jumpstart effective tissue regeneration and facilitate extensive therapeutic applications with good scalability and reproducibility. There is a growing demand for simple and effective protocols for collecting and applying MSC-EVs. Here, a detailed protocol is provided based on differential centrifugation to isolate and characterize representative EVs from cultured human MSCs, exosomes, and microvesicles for further applications. The adaptability of this method is shown for a series of downstream approaches, such as labeling, local transplantation, and systemic injection. The implementation of this procedure will address the need for simple and reliable MSC-EVs collection and application in translational research.

The present protocol describes the differential centrifugation for isolating and characterizing representative EVs (exosomes and microvesicles) from cultured human MSCs. Further applications of these EVs are also explained in this article.

Extracellular vesicles (EVs) are heterogeneous membrane nanoparticles released by most cell types, and they are increasingly recognized as physiological ...

Adipose Tissue-Derived Stem Cell Isolation and Characterization

Isolation and Identification of Mesenchymal Stem Cells Derived from Adipose Tissue of Sprague Dawley Rats

Adult mesenchymal cells have revolutionized molecular and cell biology in recent decades. They can differentiate into different specialized cell types, in addition to their great capacity for self-renewal, migration, and proliferation. Adipose tissue is one of the least invasive and most accessible sources of mesenchymal cells. It has also been reported to have higher yields compared to other sources, as well as superior immunomodulatory properties. Recently, different procedures for obtaining adult mesenchymal cells from different tissue sources and animal species have been published. After evaluating the criteria of some authors, we standardized a methodology that is applicable to different purposes and easily reproducible. A pool of stromal vascular fraction (SVF) from perirenal and epididymal adipose tissue allowed us to develop primary cultures with optimal morphology and functionality. The cells were observed adhered to the plastic surface for 24 h, and exhibited a fibroblast-like morphology, with prolongations and a tendency to form colonies. Flow cytometry (FC) and immunofluorescence (IF) techniques were used to assess the expression of the membrane markers CD105, CD9, CD63, CD31, and CD34. The ability of adipose-derived stem cells (ASCs) to differentiate into the adipogenic lineage was also assessed using a cocktail of factors (4 &#181;M insulin, 0.5 mM 3-methyl-iso-butyl-xanthine, and 1 &#181;M dexamethasone). After 48 h, a gradual loss of fibroblastoid morphology was observed, and at 12 days, the presence of lipid droplets positive to oil red staining was confirmed. In summary, a procedure is proposed to obtain optimal and functional ASC cultures for application in regenerative medicine.

Author Spotlight: Isolation and Identification of Mesenchymal Stem Cells Derived from Adipose Tissue of Sprague Dawley Rats  

This protocol describes a methodology for isolating and identifying adipose tissue-derived mesenchymal stem cells (MSCs) from Sprague Dawley rats.

Adult mesenchymal cells have revolutionized molecular and cell biology in recent decades. They can differentiate into different specialized cell types, in ...

Photobiomodulation Growth Augmentation of Hydrogel Embedded Stem Cells 

Three&#45;Dimensional Cell Culture of Adipose-Derived Stem Cells in a Hydrogel with Photobiomodulation Augmentation

Adipose-derived stem cells (ADSCs), possessing multipotent mesenchymal characteristics akin to stem cells, are frequently employed in regenerative medicine due to their capacity for a diverse range of cell differentiation and their ability to enhance migration, proliferation, and mitigate inflammation. However, ADSCs often face challenges in survival and engraftment within wounds, primarily due to unfavorable inflammatory conditions. To address this issue, hydrogels have been developed to sustain ADSC viability in wounds and expedite the wound healing process. Here, we aimed to assess the synergistic impact of photobiomodulation (PBM) on ADSC proliferation and cytotoxicity within a 3D cell culture framework. Immortalized ADSCs were seeded into 10 &#181;L hydrogels at a density of 2.5 x 103 cells and subjected to irradiation using 525 nm and 825 nm diodes at fluencies of 5 J/cm2 and 10 J/cm2. Morphological changes, cytotoxicity, and proliferation were evaluated at 24 h and 10 days post-PBM exposure. The ADSCs exhibited a rounded morphology and were dispersed throughout the gel as individual cells or spheroid aggregates. Importantly, both PBM and 3D culture framework displayed no cytotoxic effects on the cells, while PBM significantly enhanced the proliferation rates of ADSCs. In conclusion, this study demonstrates the use of hydrogel as a suitable 3D environment for ADSC culture and introduces PBM as a significant augmentation strategy, particularly addressing the slow proliferation rates associated with 3D cell culture.

Author Spotlight: Advancements in Stem Cell Regenerative Therapy Through Photobiomodulation

Here, we present a protocol demonstrating the use of hydrogel as a three-dimensional (3D) cell culture framework for adipose-derived stem cell (ADSC) culture and introducing photobiomodulation (PBM) to enhance the proliferation of ADSCs within the 3D culture setting.