Name: isolation and culture of primary mouse keratinocytes from neonatal and adult mouse skin
Uploaded: 2017-07-14T14:00:00
Description: Watch this Scientific Journal Video about Isolation and Culture of Primary Mouse Keratinocytes from Neonatal and Adult Mouse Skin at JoVE.com

This work was supported by NATIONAL INSTITUTE OF ARTHRITIS AND MUSCULOSKELETAL AND SKIN DISEASES grant (R01AR069653 to Zhang LJ), and National Institutes of Health Support (5T32AR062496-03 to CA).

All animal experiments are approved by the UCSD Institutional Animal Care and Use Committee.
1. Primary Mouse KC Isolation and Culture from Neonatal Skin
<ol>
	<li>Sacrifice the post-natal day 0-2 neonates from the C57B/6 wildtype mouse strain by decapitation using scissors. Cut off the limbs just above the wrist and ankle joints, then cut off the tail completely, leaving a small hole.</li>
	<li>To peel off the whole skin, first insert sharp scissors through the hole at the tail and ...

<ol>
	<li>Mauro, T., 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=Acute+barrier+perturbation+abolishes+the+Ca2++and+K++gradients+in+murine+epidermis:+quantitative+measurement+using+PIXE.">Acute barrier perturbation abolishes the Ca2+ and K+ gradients in murine epidermis: quantitative measurement using PIXE.</a> J Invest Dermatol. 111 (6), 1198-1201 (1998).</li><li>Menon, G. K., Grayson, S., Elias, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ionic+calcium+reservoirs+in+mammalian+epidermis:+ultrastructural+localization+by+ion-capture+cytochemistry.">Ionic calcium reservoirs in mammalian epidermis: ultrastructural localization by ion-capture cytochemistry.</a> J Invest Dermatol. 84 (6), 508-512 (1985).</li><li>Elias, P. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+the+epidermal+calcium+gradient+coincides+with+key+milestones+of+barrier+ontogenesis+in+the+rodent.">Formation of the epidermal calcium gradient coincides with key milestones of barrier ontogenesis in the rodent.</a> J Invest Dermatol. 110 (4), 399-404 (1998).</li><li>Hennings, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium+regulation+of+growth+and+differentiation+of+mouse+epidermal+cells+in+culture.">Calcium regulation of growth and differentiation of mouse epidermal cells in culture.</a> Cell. 19 (1), 245-254 (1980).</li><li>Zhang, L. J., Bhattacharya, S., Leid, M., Ganguli-Indra, G., Indra, A. 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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=The+macrophage-inducible+C-type+lectin,+mincle,+is+an+essential+component+of+the+innate+immune+response+to+Candida+albicans.">The macrophage-inducible C-type lectin, mincle, is an essential component of the innate immune response to Candida albicans.</a> J Immunol. 180 (11), 7404-7413 (2008).</li><li>Vasioukhin, V., Bauer, C., Yin, M., Fuchs, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Directed+actin+polymerization+is+the+driving+force+for+epithelial+cell-cell+adhesion.">Directed actin polymerization is the driving force for epithelial cell-cell adhesion.</a> Cell. 100 (2), 209-219 (2000).</li><li>Zhuang, L., 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=TNF+receptor+p55+plays+a+pivotal+role+in+murine+keratinocyte+apoptosis+induced+by+ultraviolet+B+irradiation.">TNF receptor p55 plays a pivotal role in murine keratinocyte apoptosis induced by ultraviolet B irradiation.</a> J Immunol. 162 (3), 1440-1447 (1999).</li><li>Lichti, U., Anders, J., Yuspa, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+short-term+culture+of+primary+keratinocytes,+hair+follicle+populations+and+dermal+cells+from+newborn+mice+and+keratinocytes+from+adult+mice+for+in+vitro+analysis+and+for+grafting+to+immunodeficient+mice.">Isolation and short-term culture of primary keratinocytes, hair follicle populations and dermal cells from newborn mice and keratinocytes from adult mice for in vitro analysis and for grafting to immunodeficient mice.</a> Nat Protoc. 3 (5), 799-810 (2008).</li><li>Dlugosz, A. A., Glick, A. B., Tennenbaum, T., Weinberg, W. C., Yuspa, S. 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R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expression+of+murine+epidermal+differentiation+markers+is+tightly+regulated+by+restricted+extracellular+calcium+concentrations+in+vitro.">Expression of murine epidermal differentiation markers is tightly regulated by restricted extracellular calcium concentrations in vitro.</a> J Cell Biol. 109 (3), 1207-1217 (1989).</li><li>Yuspa, S. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Signal+transduction+for+proliferation+and+differentiation+in+keratinocytes.">Signal transduction for proliferation and differentiation in keratinocytes.</a> Ann N Y Acad Sci. 548, 191-196 (1988).</li><li>Fang, N. X., 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=Calcium+enhances+mouse+keratinocyte+differentiation+in+vitro+to+differentially+regulate+expression+of+papillomavirus+authentic+and+codon+modified+L1+genes.">Calcium enhances mouse keratinocyte differentiation in vitro to differentially regulate expression of papillomavirus authentic and codon modified L1 genes.</a> Virology. 365 (1), 187-197 (2007).</li><li>Kolly, C., Suter, M. M., Muller, E. 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The skin epidermis functions as a critical barrier to separate and protect the body from the outside environment and damage from water loss, pathogens, heat and UV irradiation. The KCs are the predominant cell lineage of the epidermis, and primary culture of epidermal KCs is a useful tool to study and understand the biological processes of barrier formation and the response of KCs to environmental insults in vitro.
Here we describe methods to isolate and culture primary epidermal KCs ...

The skin is the largest organ in the body with the epidermis as the outer most layer. The epidermis plays a critical role in forming an intact epidermal barrier to separate the body from the environment, and thus prevents water loss and provides protection from environmental insults, such as allergens, pathogens and UVB exposure. The epidermis develops from a single layer of undifferentiated basal keratinocytes (KCs) into a multi-layered stratified epithelium consisting of a basal layer, followed by a spinous layer, granular layer, and stratum corneum. Basal KCs, consisting of both epidermal stem cells and transit-amplifying cells, are proliferative and undifferentiated. As basal KCs exit the cell cycle, the cells commit to differentiation and gradually migrate towards the surface of the epidermis, accompanied by the maturation of cell-cell junctions and formation of an epidermal permeability barrier (EPB). The KCs at the spinous layer express early differentiation markers such as Keratin 10 (K10); as the KCs migrate to the granular layer, the cells express late differentiation markers such as Filaggrin (FLG), Loricrin (LOR) and Involucrin (INV). At the stratum corneum, the KCs become terminally differentiated corneocytes, which are eventually shed off through desquamation as new cells replace them.
Calcium is considered the most physiological agent in the epidermis and triggers differentiation in vitro and in vivo in a similar manner. In normal skin epidermis, calcium ions form a characteristic &#34;concentration gradient&#34;, increasing in concentration towards the skin surface1,2,3. The calcium concentration rises from low levels in the lowest sublayers (basal and spinous layers) to a peak in the upper granular layer and then drops to negligible levels in the most superficial layer (stratum corneum). The calcium gradient also develops coincidently with the emergence of a component permeability barrier, which supports that calcium signaling plays a critical role of KC differentiation. In vitro, low calcium (0.02-0.1 mM) maintains the proliferation of basal KCs as a monolayer, whereas high calcium (&#62;0.1 mM) induces a rapid and irreversible commitment of the cells to terminal differentiation as demonstrated by tight-junction formation and induction of LOR and INV upon high calcium treatment to the basal KCs4,5.
In addition to barrier formation, epidermal KCs are also an important component of the skin&#39;s innate immune system. In response to pathogens or damaged-associated molecular patterns (DAMPs) released upon UVB irradiation or injury, KCs can produce large amounts of inflammatory cytokines, such as TNF&#945;, IL6 and IFN&#946;, leading to immune system activation6,7,8,9. Although proper inflammatory signaling from KCs is required for pathogen clearance, uncontrolled inflammatory response may trigger the development of auto-inflammatory skin diseases, such as psoriasis and rosacea6,8.
Overall, KCs play a vital role in maintaining the intact skin barrier and initiating an immune response upon pathogen invasion or environmental insults. Therefore, primary culture of epidermal KCs is a useful technique to study the epithelial biology, KC differentiation, as well as KC-stimulated innate immune responses. The isolation and culture of primary mouse epidermal KCs can be a challenging process due to KC&#39;s susceptibility and sensitivity to various external stimulants. Here we describe a method to isolate and culture KCs from either neonatal mouse skin or adult mouse tail skin. For adult KC isolation, we do not use mouse dorsal skin because isolating sufficient quantities of viable KCs from this tissue can be difficult for the following reasons: First, the adult dorsal skin at the resting phase of the hair cycle (telogen) consists of a thin epidermis with only 1-2 layers of cells, leading to a low cell yield and inefficient separation of the epidermis from the dermis, which is the critical step for successful KC isolation. Second, the high hair follicle density that is present on adult dorsal skin further contributes to the difficulty in separating epidermis from the dermis. Instead, we routinely use tail skin as the source for adult mouse KCs as this epithelium is thicker with 3-5 layers of epidermal KCs. It also has a lower hair follicle density, which does not interfere with the epidermal separation, thus allowing KC isolation from any adult mouse tail skin regardless of the age and hair cycling stage of the mouse. The isolated neonatal KCs are seeded to gelatin-coated culture dishes, whereas collagen-coated dishes are used to seed isolated adult KCs due to the impaired ability of the adult cells to adhere compared to their neonatal counterparts. To culture mouse KCs, low calcium basal medium is supplemented with dGS, which contains epidermal growth factor (EGF), bovine transferrin, insulin-like growth factorc1 (IGF1), prostaglandin E2 (PGE2), bovine serum albumin (BSA) and hydrocortisone. Between 2-4 days after the initial plating, most of the differentiated KCs can be washed away during daily medium changes, and the remaining adherent cells show typical cobblestone morphology4, are proliferating, and do not express the early differentiation marker K10.

<table width="633">
	<tbody>
		<tr height="100">
			<td height="100" style="width:171px;height:100px;">C57BL/6 neonates or adult wildtype mice</td>
			<td style="width:177px;">Jackson Laboratory</td>
			<td style="width:119px;">000664</td>
			<td style="width:167px;">Wildtype mice (originally purchased from Jackson Laboratory) are breeded and maintained in animal vivarium at UCSD.</td>
		</tr>
		<tr height="60">
			<td height="60" style="width:171px;height:60px;">KC basal medium (EpiLife)</td>
			<td style="width:177px;">Invitrogen, Carlsbad, CA</td>
			<td style="width:119px;">MEPICF500</td>
			<td style="width:167px;">basal medium for keratinocyte culture with 0.06 mM CaCl2</td>
		</tr>
		<tr height="60">
			<td height="60" style="width:171px;height:60px;">Defined Growth Supplement (dGS)</td>
			<td style="width:177px;">Invitrogen, Carlsbad, CA</td>
			<td style="width:119px;">S0125</td>
			<td style="width:167px;">defined growth supplements for culture medium</td>
		</tr>
		<tr height="40">
			<td height="40" style="width:171px;height:40px;">Dispase powder</td>
			<td style="width:177px;">Invitrogen, Carlsbad, CA</td>
			<td style="width:119px;">17105041</td>
			<td style="width:167px;">enzyme to dissociate the epidermis from dermis</td>
		</tr>
		<tr height="40">
			<td height="40" style="width:171px;height:40px;">Attachment Factor</td>
			<td style="width:177px;">Invitrogen, Carlsbad, CA</td>
			<td style="width:119px;">S006100</td>
			<td style="width:167px;">gelatin-based coating material</td>
		</tr>
		<tr height="40">
			<td height="40" style="width:171px;height:40px;">Coating Matrix</td>
			<td style="width:177px;">Invitrogen, Carlsbad, CA</td>
			<td style="width:119px;">R011K</td>
			<td style="width:167px;">Collagen-based coating material</td>
		</tr>
		<tr height="80">
			<td height="80" style="width:171px;height:80px;">TrypLE</td>
			<td style="width:177px;">Invitrogen, Carlsbad, CA</td>
			<td style="width:119px;">12604-013</td>
			<td style="width:167px;">A gentle trypsin-like enzyme to dissociate keratinocytes from epidermal sheet</td>
		</tr>
		<tr height="40">
			<td height="40" style="width:171px;height:40px;">100 &#956;m Cell Strainer Nylon mesh</td>
			<td style="width:177px;">Corning</td>
			<td style="width:119px;">352360</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="60">
			<td height="60" style="width:171px;height:60px;">CCK-8 cell viability Kit</td>
			<td style="width:177px;">Dojindo Molecular Technologies, Rockville, MD</td>
			<td style="width:119px;">CK04-11</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="width:171px;height:40px;">Mouse TNF (Mono/Mono) ELISA Set II</td>
			<td style="width:177px;">BD Biosciences, San Jose, CA</td>
			<td style="width:119px;">555268</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="width:171px;height:40px;">Corded Hand-Held UV Lamps</td>
			<td style="width:177px;">Spectronics, Westbury, NY</td>
			<td style="width:119px;">EB-280C</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="width:171px;height:20px;">8-watt UV tubes</td>
			<td style="width:177px;">Spectronics, Westbury, NY</td>
			<td style="width:119px;">BLE-8T312</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="width:171px;height:40px;">Light Inverted Microscope for cell culture</td>
			<td style="width:177px;">ZEISS, Jena, Germany</td>
			<td style="width:119px;">Axio Observer</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="width:171px;height:20px;">Fluorescent Microscope</td>
			<td style="width:177px;">Olympus</td>
			<td style="width:119px;">BX41</td>
			<td style="width:167px;"></td>
		</tr>
	</tbody>
</table>

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.

High calcium induced terminal differentiation of neonatal and adult KCs. The primary mouse epidermal KCs plated and maintained at 0.06 mM CaCl2 grew as a monolayer, and individual cells had a polygonal shape with distinct intercellular space, showing a cobblestone appearance when confluent (Figure 1A and Figure 2A). Elevating the CaCl2 to 0.2 mM induced a rapid morphology change of the cells...

Watch this Scientific Journal Video about Isolation and Culture of Primary Mouse Keratinocytes from Neonatal and Adult Mouse Skin at JoVE.com

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

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 ...

The overall goal of this procedure is to isolate primary mouse keratinocytes from neonatal or adult mouse skin from their in-vitro differentiation or to study their innate immune responses to UVb exposure. This method can help answer key questions in the epidermal biology field about how keratinocyte differentiation is regulated or how epidermal keratinocytes respond to external stimuli. The main advantages of this technique are that the keratinocytes can be conventionally isolated from both mouse, neonatal and adult mouse skin and that they can be cultured be with our serum.Demonstrating the procedure with me will be, Fengwu Li, a staff research associate from my laboratory. Begin by removing the limbs of a wild type C57 BL6 postnatal day zero to two mouse neonatal, just above the wrist entangled joints and cut off the tail completely leaving a small ball. Insert sharp scissors through the tail hole and cut the skin along the dorsal midline of the body to the opening on the neck.Using one forceps, grasp the exposed body and use another forceps to grasp the skin. Then gently peel the whole skin off of the body and over the leg stumps in one continuous motion, taking care not to break the skin into pieces. Rinse the peeled skin with 50 millimeters of sterile PBS in a 10 centimeter petri dish and place the skin into a two milliliter tube containing ice cold, dispase digestion buffer, taking care that the skin is not folded.When all of the neonatal skin sheets have been collected, place the tube on a rotator at four degree celsius overnight. The next morning, dispense the tube contents into a new petri dish. Then, transfer each piece of tissue into a new petri dish containing 50 milliliters of sterile PBS to remove any excess dispase.Use two forceps, place the skin samples into individual petri dishes, epidermal side down and carefully stretch the skin folds so that the pieces are fully extended on the dish bottoms. Add 500 microliters of a trypsin based digestion solution to each dish and to use one forceps to slowly lift each dermis up and away from the epidermis, while holding the epidermis in place with a second forceps. Float the isolated epidermises in the trypsin solution with the basal levels facing down and cover the dishes.Then incubate the skin pieces on a horizontal shaker at room temperature, with gentle agitation for 20 minutes. At the end of the incubation, add two milliliters of supplemented keratinocyte growth medium per epidermis to each petri dish and use forceps to vigorously rub the epidermal sheets releasing the single cells from the skin tissue. When the medium becomes turbid, tilt the dishes to allow the collection and transfer of the cell suspensions into a new tube.Leaving the remaining epidermal tissue in the dish. After the third round of cell collection, gently triturate the pooled cell suspension a few times to break up any cell clumps, and filter the cells through a 100 micron strainer into a new 50 milliliter conical tube. Collect the cells by centrifugation and gently re-suspend the pellet in one milliliter of cold keratinocyte growth medium on ice, for counting.Seed the cells at a 5x10 to the fourth centimeter squared density in keratinocyte growth medium in cultured dishes, pre-coated with an extra-cellular matrix product that promotes cell attachment. Then incubate the cells at 37 degrees celsius and 5%carbon dioxide, replacing the supernatant daily with fresh medium until the cells have reached the appropriate confluency. To isolate keratinocytes from an adult mouse, first remove the tail at its base.Followed by removal of approximately two millimeters of the tail tip so there is visible hole. Use a sharp blade to cut along the tail skin from the base to the tip. Then, using one forceps to grasp the exposed tail bone and another forceps to grasp the skin, gently peel the skin tissue from the bone in one continuous motion.Cut the peeled skin at the midline, so that each piece is less than two to three centimeters long, and rinse the pieces in 15 milliliters of sterile PBS in a 10 centimeter petri dish. Place the skins from up to five tails into a 15 milliliter tube containing up to 12 milliliters of ice cold, dispase digestion buffer and incubate the skins overnight at four degree celsius, with rotation. The next morning, isolate the epidermal cells from the partially digested skin sheets, as just demonstrated for the neonatal skin samples.Then seed the isolated adult keratinocyte cells at 1x10 to the fifth power centimeter square density in kerationcyte growth medium in culture dishes pre-coated with collagen. Changing the supernatant daily, until the cells reach the appropriate confluency. To induce the terminal differentiation of either type of keratinocyte culture, add calcium chloride for the cells at 2 nanomolar concentrations.For UVb irradiation induced death, replace the growth medium from a confluent keratinocyte culture, with 500 microliters of PBS and briefly expose the cells to 15 millijoules per square centimeter of UVb. Replace the PBS with fresh growth medium and return the cells to the cell culture incubator for six hours. After collecting the conditioned medium at each experimental time point, quantify the cell viability by the cell counting kit aid viability assay, according to the manufacturer's instructions.Then measure the TNL for release by the irradiated keratinocytes into conditioned medium according to standard protocols. Primary mode's epidermal keratinocytes plated and maintained at 06 nanomolar calcium chloride, grew as a monolayer with the individual cells exhibiting a polygonal shape with distinct inter-cellular spaces and demonstrating an overall cobblestone appearance when confluent. Elevating the calcium chloride to 2 millimolar, induces a rapid morphology change in the cells.With the cells becoming flattened and the distinct inter-cellular space becoming less apparent within eight hours. And the cell to cell adhesion between the tight junctions becoming more striking within 24 hours. By 48 to 72 hours, the formation of the cornified cell envelope and the vertical cell stratification, become apparent.Phalloidin staining of high calcium treated keratinocytes, reveals the formation of actin fiber-rich filopodial projections between adjacent cells, as early as three hours, post calcium switch. Between six and 24 hours, further actin fiber remodeling becomes evident. With the prominent amount of cell stratification apparent at 48 hours post high calcium exposure.UVb irradiation triggers the time dependent cell death of keratinocyte cultures as evidenced by both phase contrast imaging and cell viability assay. Indeed, by 24 hours, nearly all of the cells become rounded and detached, and are measured as unviable by cell viability assay. Most likely due to the high levels of TNF alpha, relieved by the keratinocytes, in response to UVb exposure.While attempting this procedure, it's important to remember that to keep the dissociated keratinocyte on ice at all times and to plate the cells as soon as possible to avoid terminal differentiation of the isolated cells. After its development, this technique paved the way for researchers in the field of epidermal biology to explore the roles of keratinocytes in skin development and in an innate immune defense of the skin. After watching this video, you should have a good understanding of how to isolate and culture primary epidermal keratinocytes from neonatal or adult mouse skin.

isolation-culture-primary-mouse-keratinocytes-from-neonatal-adult

Research

JoVE Journal

Biology

In vivo Imaging and Therapeutic Treatments in an Orthotopic Mouse Model of Ovarian Cancer

Human cancer and response to therapy is better represented in orthotopic animal models. This paper describes the development of an orthotopic mouse model of ovarian cancer, treatment of cancer via oral delivery of drugs, and monitoring of tumor cell behavior in response to drug treatment in real time using in vivo imaging system. In this orthotopic model, ovarian tumor cells expressing luciferase are applied topically by injecting them directly into the mouse bursa where each ovary is enclosed. Upon injection of D-luciferin, a substrate of firefly luciferase, luciferase-expressing cells generate bioluminescence signals. This signal is detected by the in vivo imaging system and allows for a non-invasive means of monitoring tumor growth, distribution, and regression in individual animals. Drug administration via oral gavage allows for a maximum dosing volume of 10 mL/kg body weight to be delivered directly to the stomach and closely resembles delivery of drugs in clinical treatments. Therefore, techniques described here, development of an orthotopic mouse model of ovarian cancer, oral delivery of drugs, and in vivo imaging, are useful for better understanding of human ovarian cancer and treatment and will improve targeting this disease.

In vivo Imaging and Therapeutic Treatments in an Orthotopic Mouse Model of Ovarian Cancer

Orthotopic animal models of ovarian cancer replicate better human disease and therefore enhance our understanding of cancer progression and tumor response to therapy. A mouse model receives an intrabursal injection of luciferase-expressing ovarian tumor cells. Treatment is administered via oral gavage. Tumor growth is monitored by in vivo imaging system.

Human cancer and response to therapy is better represented in orthotopic animal models.  This paper describes the development of an orthotopic mouse model ...

Isolation and Culture of Pulmonary Endothelial Cells from Neonatal Mice

Endothelial cells provide a useful research model in many areas of vascular biology. Since its first isolation 1, human umbilical vein endothelial cells (HUVECs) have shown to be convenient, easy to obtain and culture, and thus are the most widely studied endothelial cells. However, for research focused on processes like angiogenesis, permeability or many others, microvascular endothelial cells (ECs) are a much more physiologically relevant model to study 2. Furthermore, ECs isolated from knockout mice provide a useful tool for analysis of protein function ex vivo. Several approaches to isolate and culture microvascular ECs of different origin have been reported to date 3-7, but consistent isolation and culture of pure ECs is still a major technical problem in many laboratories. Here, we provide a step-by-step protocol on a reliable and relatively simple method of isolating and culturing mouse lung endothelial cells (MLECs). In this approach, lung tissue obtained from 6- to 8-day old pups is first cut into pieces, digested with collagenase/dispase (C/D) solution and dispersed mechanically into single-cell suspension. MLECS are purified from cell suspension using positive selection with anti-PECAM-1 antibody conjugated to Dynabeads using a Magnetic Particle Concentrator (MPC). Such purified cells are cultured on gelatin-coated tissue culture (TC) dishes until they become confluent. At that point, cells are further purified using Dynabeads coupled to anti-ICAM-2 antibody. MLECs obtained with this protocol exhibit a cobblestone phenotype, as visualized by phase-contrast light microscopy, and their endothelial phenotype has been confirmed using FACS analysis with anti-VE-cadherin 8 and anti-VEGFR2 9 antibodies and immunofluorescent staining of VE-cadherin. In our hands, this two-step isolation procedure consistently and reliably yields a pure population of MLECs, which can be further cultured. This method will enable researchers to take advantage of the growing number of knockout and transgenic mice to directly correlate in vivo studies with results of in vitro experiments performed on isolated MLECs and thus help to reveal molecular mechanisms of vascular phenotypes observed in vivo.

Here, we describe a protocol for isolation and culture of murine pulmonary endothelial cells. This method comprises mechanic and enzymatic lung tissue dissociation as well as a 2-step purification process using anti-PECAM-1 and anti-ICAM-2 antibodies conjugated to magnetic beads, which produces a pure endothelial cell population of mostly microvascular origin.

Endothelial cells provide a useful research model in many areas of vascular biology. Since its first isolation 1, human umbilical vein endothelial cells ...

Isolation and Culture of Adult Epithelial Stem Cells from Human Skin

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

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

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

Isolation and Culture of Neonatal Mouse Cardiomyocytes

Cultured neonatal cardiomyocytes have long been used to study myofibrillogenesis and myofibrillar functions. Cultured cardiomyocytes allow for easy investigation and manipulation of biochemical pathways, and their effect on the biomechanical properties of spontaneously beating cardiomyocytes.	
The following 2-day protocol describes the isolation and culture of neonatal mouse cardiomyocytes. We show how to easily dissect hearts from neonates, dissociate the cardiac tissue and enrich cardiomyocytes from the cardiac cell-population. We discuss the usage of different enzyme mixes for cell-dissociation, and their effects on cell-viability. The isolated cardiomyocytes can be subsequently used for a variety of morphological, electrophysiological, biochemical, cell-biological or biomechanical assays. We optimized the protocol for robustness and reproducibility, by using only commercially available solutions and enzyme mixes that show little lot-to-lot variability. We also address common problems associated with the isolation and culture of cardiomyocytes, and offer a variety of options for the optimization of isolation and culture conditions.

Primary mouse cardiomyocyte cultures are one of the pivotal tools for the investigation of myofibrillar organization and function. The following protocol describes the isolation and culture of primary cardiomyocytes from neonatal mouse hearts. The resulting cardiomyocyte cultures may be subsequently used for a variety of biomechanical, biochemical and cell-biological assays.

Cultured neonatal cardiomyocytes have long been used to study  myofibrillogenesis and myofibrillar functions. Cultured cardiomyocytes allow  for easy ...

Isolation, Culture, and Functional Characterization of Adult Mouse Cardiomyoctyes

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

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

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

Isolation and Culture of Mouse Primary Pancreatic Acinar Cells

This protocol permits rapid isolation (in less than 1 hr) of murine pancreatic acini, making it possible to maintain them in culture for more than one week. More than 20 x 106 acinar cells can be obtained from a single murine pancreas. This protocol offers the possibility to independently process as many as 10 pancreases in parallel. Because it preserves acinar architecture, this model is well suited for studying the physiology of the exocrine pancreas in vitro in contrast to cell lines established from pancreatic tumors, which display many genetic alterations resulting in partial or total loss of their acinar differentiation.

In this publication, we describe a rapid and convenient procedure for isolating and culturing primary pancreatic acinar cells from the murine pancreas. This method constitutes a valuable approach to study the physiology of fresh primary normal/untransformed exocrine pancreatic cells.

This protocol permits rapid isolation (in less than 1 hr) of murine pancreatic acini, making it possible to maintain them in culture for more than one ...

Isolation of Primary Myofibroblasts from Mouse and Human Colon Tissue

The myofibroblast is a stromal cell of the gastrointestinal (GI) tract that has been gaining considerable attention for its critical role in many GI functions. While several myofibroblast cell lines are commercially available to study these cells in vitro, research results from a cell line exposed to experimental cell culture conditions have inherent limitations due to the overly reductionist nature of the work. Use of primary myofibroblasts offers a great advantage in terms of confirming experimental findings identified in a cell line. Isolation of primary myofibroblasts from an animal model allows for the study of myofibroblasts under conditions that more closely mimic the disease state being studied. Isolation of primary myofibroblasts from human colon tissue provides arguably the most relevant experimental data, since the cells come directly from patients with the underlying disease. We describe a well-established technique that can be utilized to isolate primary myofibroblasts from both mouse and human colon tissue. These isolated cells have been characterized to be alpha-smooth muscle actin and vimentin-positive, and desmin-negative, consistent with subepithelial intestinal myofibroblasts. Primary myofibroblast cells can be grown in cell culture and used for experimental purposes over a limited number of passages.

The myofibroblast is an influential stromal cell of the gastrointestinal tract that regulates important physiologic processes in both normal and disease states. We describe a technique that allows for the isolation of primary myofibroblasts from both mouse and human colon tissue, which can be utilized for in vitro experimentation.

The myofibroblast is  a stromal cell of the gastrointestinal (GI) tract that has been gaining  considerable attention for its critical role in many GI ...

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

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

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

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

Isolation and Primary Culture of Mouse Aortic Endothelial Cells

The vascular endothelium is essential to normal vascular homeostasis. Its dysfunction participates in various cardiovascular disorders. The mouse is an important model for cardiovascular disease research. This study demonstrates a simple method to isolate and culture endothelial cells from the mouse aorta without any special equipment. To isolate endothelial cells, the thoracic aorta is quickly removed from the mouse body, and the attached adipose tissue and connective tissue are removed from the aorta. The aorta is cut into 1 mm rings. Each aortic ring is opened and seeded onto a growth factor reduced matrix with the endothelium facing down. The segments are cultured in endothelial cell growth medium for about 4 days. The endothelial sprouting starts as early as day 2. The segments are then removed and the cells are cultured continually until they reach confluence. The endothelial cells are harvested using neutral proteinase and cultured in endothelial cell growth medium for another two passages before being used for experiments. Immunofluorescence staining indicated that after the second passage the majority of cells were double positive for Dil-ac-LDL uptake, Lectin binding, and CD31 staining, the typical characteristics of endothelial cells. It is suggested that cells at the second to third passages are suitable for in vitro and in vivo experiments to study the endothelial biology. Our protocol provides an effective means of identifying specific cellular and molecular mechanisms in endothelial cell physiopathology.

The vascular endothelial cells play a significant role in many important cardiovascular disorders. This article describes a simple method to isolate and expand endothelial cells from the mouse aorta without using any special equipment. Our protocol provides an effective means of identifying mechanisms in endothelial cell physiopathology.

The vascular endothelium is essential to normal vascular homeostasis. Its dysfunction participates in various cardiovascular disorders. The mouse is an ...

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 ...