The authors thank Xiu-Ping Wang for initial help with DESC cultures. The authors are funded in part by fellowships and grants from the National Institutes of Health (K99-DE022059 to A.H.J., K12-GM081266 to M.G.C., K08-DE022377-02 to O.H., and R01-DE021420 to O.D.K.).

1. Dissect Lower Hemi-mandibles from Adult Mouse
<ol>
	<li>Prior to performing this protocol, obtain necessary institutional approval and be sure to comply with all animal care guidelines. Euthanize animal using standard IACUC approved procedures. For this work CO2 asphyxiation was used followed by cervical dislocation.
	<ol>
		<li>OPTIONAL: Separate head from the rest of the body using a razor blade.</li>
	</ol>
	</li>
	<li>Remove skin from the lower lip to the neckline.</li>
	<li>Using a scalpel, make an incision between the two lower incisors, which are loosely connected. Upon applying pressure, the mandible will be split into two halves.</li>
	<li>Wedge the scalpel between the condyle of the jaw and the temporal mandibular joint and cut alongside the jaw muscle to detach the jaw.</li>
	<li>Remove all muscle, tendon, and ligament until only the bone remains.</li>
</ol>
2. Isolate the Incisor
<ol>
	<li>Using a #15 scalpel, carefully shave off the bone at a 45&#176;&#160;angle from the distal end to the proximal end of the membranous region. Use the tip of the scalpel to pick away any remaining bone including the bone fragments at the edge. Slowly start to pick away at the lingual cortical plate of the mandible, starting just below the 3rd molar.</li>
	<li>Continue until the incisor is clean, working carefully towards the area containing the CL.</li>
	<li>Remove inferior alveolar nerve bundle.</li>
	<li>Make a clean cut to first remove the bone and tissues proximal to the CL.</li>
	<li>Make a second cut distally with the scalpel, roughly below the 2nd molar. The proximal incisor region is then dissected out by inserting the scalpel between the bone and the medial surface of the proximal incisor. This must be carefully done, so as not to tear the tissue. The incision motion is proximal-distal. 
	ALTERNATIVE STEP: 
	Remove as much bone as possible along the area above the incisor. Once area is cleared, carefully remove entire incisor using a size 5 forceps to handle the enamel portion closest to CL region.</li>
	<li>Place dissected tissue (either isolated CL as in Figure 3E, or entire incisor as in alternative Step 2.5) in 2% collagenase in 1X PBS for 3-4 hr&#160;at 4 &#176;C in a low adherence plate. For 1-10 incisors, use 100 &#956;l per well in a 12-well plate. For greater than 10 incisors, use 500 &#956;l per well in a 6-well low adherence plate.</li>
</ol>
3. Microdissect the Labial Cervical Loop
<ol>
	<li>Remove CL region from the collagenase and place in cold DMEM/F12 media.</li>
	<li>Pull gently at the lower end of the CL using either size 5 forceps or an insulin syringe (1 cc, 28 G &#189;); the mesenchyme will fall apart while the epithelium remains intact. The CL and the adjacent epithelium that extends laterally as a &#8220;wing-like&#8221; structure will be visible.</li>
	<li>Remove the apical bud from the adjacent epithelium by making a V-shaped incision on either side, and immediately place in cold DMEM/F12 on ice.</li>
	<li>Repeat for all CLs, collect in 1.5 ml microfuge tube.</li>
	<li>Spin down microfuge tube with specimens, remove media, replace with 100 &#956;l cell detachment solution.</li>
	<li>Incubate tissues in cell detachment solution for 30 min at 37 &#176;C.</li>
	<li>Dissociate the tissues to produce a single cell suspension by gently pipetting up and down using a 1,000 &#956;l low-adhesion pipette tip. Cells can also be placed through a sterile cell strainer to achieve dissociation.</li>
	<li>Count cells with hemocytometer, plate on tissue culture plastic or other desired material.</li>
</ol>
4. Primary Culture of DESCs
<ol>
	<li>Plate cells in a 6-well plate at 1-6 x 104 cell/ml in DESC media, which consists of DMEM/F12 supplemented with mouse EGF recombinant protein at a concentration of 20 ng/ml, FGF recombinant protein at a concentration of 25 ng/ml, 1X B27 supplement, and 1% antibiotic solution (penicillin, 100 U/ml, streptomycin, 50 &#956;g/ml).</li>
	<li>Grow cells plated on a 6-well plate at 37&#160;&#176;C in 5% CO2 in 1 ml of DESC media. Do not disturb initial cultures for 5 days after plating to allow cell adhesion and colony formation.</li>
	<li>For the first media change, replace half of the volume (500 &#956;l) of old media with half volume (500 &#956;l) of new media. Check colonies under microscope when changing media.</li>
	<li>After the first media change, continue to change media (1-2 ml) every 2 days. Check colonies under microscope when changing media.</li>
</ol>
5. Passage DESCs
<ol>
	<li>Aspirate media and wash cells 3x&#160;with pre-warmed PBS.</li>
	<li>Add pre-warmed 0.25% Trypsin-EDTA in saline solution and incubate at 37 &#176;C for 10-15 min&#160;for the DESCs to detach.</li>
	<li>Add DESC media to neutralize the trypsin, gently pipette along tissue culture plate to collect the cells, and place in a 15 ml conical tube.</li>
	<li>Spin down cells at 800 x g for 2 min.</li>
</ol>

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The authors have no conflicts of interest to disclose.

Epithelial cells were first successfully cultured over 40 years ago21-24, and more recently, successful isolation of epithelial stem cells25-27 has advanced our knowledge of epithelial biology. We report a protocol for isolating the DESCs of the adult mouse incisor, a relatively understudied population of stem cells that has the potential to yield important insights into dental biology and enamel formation. This protocol was initially based on previous reports of epithelial stem cell isolation from ...

One of the unique characteristics of vertebrates is the evolution of teeth. The tooth has become an important model system for many areas of research, as the molecular pathways and morphological specializations relevant to this organ have been investigated from several perspectives, including by developmental and evolutionary biologists5. More recently, the field of regenerative medicine has begun to gain valuable insights using the tooth as a model. In particular, the discovery of dental epithelial stem cells has been an important advance6-13.
All rodents possess continuously growing incisors whose growth is fueled by stem cells, making these teeth an accessible model system to study adult stem cell regulation. Labeling experiments in the 1970s10,11, followed by genetic lineage tracing experiments8,9,12,14, have demonstrated that DESCs reside in the proximal region of the incisor. The stem cell progeny in the epithelial compartment on the labial side move out of the putative niche, known as the labial cervical loop (CL), and contribute to a population of cells called transit-amplifying (T-A) cells (Figure 1). Specifically, DESCs reside in the outer enamel epithelium (OEE) and stellate reticulum (SR)8,9,14, and the inner enamel epithelium (IEE) gives rise to the T-A cells that progress through a limited number of cell cycles and then move distally along the length of the incisor (Figure 1). The differentiating ameloblasts in the mouse incisor continue to move distally along the incisor at a remarkable rate of approximately 350 &#181;m in a single day15,16. As they move, the cells differentiate into mature ameloblasts and stratum intermedium (SI) cells. After depositing the full thickness of enamel matrix, many of the ameloblasts undergo apoptosis, and the remaining cells shrink in size and regulate enamel maturation17. The lineage of the other cell types in the labial CL, such as the SR, is less clear, and data regarding the stem cells in the mesenchyme18 and in the lingual CL are only beginning to emerge.
Using the mouse incisor model, a number of groups have worked to elucidate the genetic pathways and cell biological processes involved in natural stem cell-based organ renewal. However, the labial CL contains a relatively small number of cells, estimated to be about 5,000 per mouse incisor, which makes working with primary cells challenging. Therefore, efforts have been made to culture and expand these cells in vitro6,16,19,20&#160;in order to open new doors to experimental approaches that are not achievable in vivo. The most recent study has demonstrated that these cells can both self-renew and differentiate into amelogenin expressing cells when cultured13. Here, we describe and demonstrate a method for the reliable and consistent culture of cells from the mouse labial CL.

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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 mouse hemi-mandible comprises one continuously growing incisor and three rooted molars (Figure 1A). All teeth consist of dentin and enamel, the two mineralized components of the tooth crown (Figures 1A and 1A&#39;). The incisor houses two stem cell niches called the labial CL and lingual CL, and enamel is formed exclusively on the labial side (Figure 1A&#39;). DESCs are responsible for incisor enamel formation and are housed in the labial CL, specifi...

Watch this Scientific Journal Video about Isolation and Culture of Dental Epithelial Stem Cells from the Adult Mouse Incisor at JoVE.com

Isolation and Culture of Dental Epithelial Stem Cells from the Adult 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-culture-dental-epithelial-stem-cells-from-adult-mouse

Research

JoVE Journal

Biology

15.1K Aufrufe.  University of California, San Francisco.  Das kontinuierlich wachsende Maus Schneidezahn stellt ein Modell für die Untersuchung Erneuerung der Zahngewebe aus Zahn epithelialen Stammzellen (DESC). Ein robustes System für konsistent und zuverlässig diese Zellen von den Schneide erhalten und in vitro expandiert sie hier berichtet wird. 

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

Isolation of Retinal Stem Cells from the Mouse Eye

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

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

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

Isolation and Culture of Adult Epithelial Stem Cells from Human Skin

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

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

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

Generation of Mice Derived from Induced Pluripotent Stem Cells

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

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

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

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

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

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

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

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

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

Na&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 ...

Induction and Analysis of Epithelial to Mesenchymal Transition

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

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

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

Isolation, Culture and Transduction of Adult Mouse Cardiomyocytes

Cultured cardiomyocytes can be used to study cardiomyocyte biology using techniques that are complementary to in vivo systems. For example, the purity and accessibility of in vitro culture enables fine control over biochemical analyses, live imaging, and electrophysiology. Long-term culture of cardiomyocytes offers access to additional experimental approaches that cannot be completed in short term cultures. For example, the in vitro investigation of dedifferentiation, cell cycle re-entry, and cell division has thus far largely been restricted to rat cardiomyocytes, which appear to be more robust in long-term culture. However, the availability of a rich toolset of transgenic mouse lines and well-developed disease models make mouse systems attractive for cardiac research. Although several reports exist of adult mouse cardiomyocyte isolation, few studies demonstrate their long-term culture. Presented here, is a step-by-step method for the isolation and long-term culture of adult mouse cardiomyocytes. First, retrograde Langendorff perfusion is used to efficiently digest the heart with proteases, followed by gravity sedimentation purification. After a period of dedifferentiation following isolation, the cells gradually attach to the culture and can be cultured for weeks. Adenovirus cell lysate is used to efficiently transduce the isolated cardiomyocytes. These methods provide a simple, yet powerful model system to study cardiac biology.

This protocol describes a step-by-step method for the reproducible isolation and long-term culture of adult mouse cardiomyocytes with high yield, purity, and viability.

Cultured cardiomyocytes can be used to study cardiomyocyte biology using techniques that are complementary to in vivo systems. For example, the purity and ...

Isolation and Culture of Primary Mouse Keratinocytes from Neonatal and Adult Mouse Skin

The keratinocyte (KC) is the predominant cell type in the epidermis, the outermost layer of the skin. Epidermal KCs play a critical role in providing skin defense by forming an intact skin barrier against environmental insults, such as UVB irradiation or pathogens, and also by initiating an inflammatory response upon those insults. Here we describe methods to isolate KCs from neonatal mouse skin and from adult mouse tail skin. We also describe culturing conditions using defined growth supplements (dGS) in comparison to chelexed fetal bovine serum (cFBS). Functionally, we show that both neonatal and adult KCs are highly responsive to high calcium-induced terminal differentiation, tight junction formation and stratification. Additionally, cultured adult KCs are susceptible to UVB-triggered cell death and can release large amounts of TNF upon UVB irradiation. Together, the methods described here will be useful to researchers for the setup of in vitro models to study epidermal biology in the neonatal mouse and/or the adult mouse.

Epidermal keratinocytes form a functional skin barrier and are positioned at the front line of host defense against external environmental insults. Here we describe methods for isolation and primary culture of epidermal keratinocytes from neonatal and adult mouse skin, and induction of terminal differentiation and UVB-triggered inflammatory response from keratinocytes.

The keratinocyte (KC) is the predominant cell type in the epidermis, the outermost layer of the skin. Epidermal KCs play a critical role in providing skin ...

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

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

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

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

Isolation and Culture of Primary Oral Keratinocytes from the Adult Mouse Palate

For years, most studies involving keratinocytes have been conducted using human and mouse skin epidermal keratinocytes. Recently, oral keratinocytes have attracted attention because of their unique function and characteristics. They maintain the homeostasis of the oral epithelium and serve as resources for applications in regenerative therapies. However, in vitro studies that use oral primary keratinocytes from adult mice have been limited due to the lack of an efficient and well-established culture protocol. Here, oral primary keratinocytes were isolated from the palate tissues of adult mice and cultured in a commercial low-calcium medium supplemented with a chelexed-serum. Under these conditions, keratinocytes were maintained in a proliferative or stem cell-like state, and their differentiation was inhibited even after increased passages. Marker expression analysis showed that the cultured oral keratinocytes expressed the basal cell markers p63, K14, and &#945;6-integrin and were negative for the differentiation marker K13 and the fibroblast marker PDGFR&#945;. This method produced viable and culturable cells suitable for downstream applications in the study of oral epithelial stem cell functions in vitro.

The present protocol describes the isolation and culture of oral keratinocytes derived from the adult mouse palate. An evaluation method using immunostaining is also reported.

For years, most studies involving keratinocytes have been conducted using human and mouse skin epidermal keratinocytes. Recently, oral keratinocytes have ...