The authors would like to acknowledge funding support from the National Health and Medical Research Council (NHMRC) of Australia (Project Grant ID: 632512). Louise Dunn was supported by an NHMRC Early Career Fellowship and Christina Bursill by a National Heart Foundation Career Development Fellowship.

1. Preparation of Splints and Occlusive Dressings
<ol>
 <li>Outline 10 mm circles on 0.5 mm thick silicone sheeting and use scissors or a biopsy punch to create silicone disks.</li>
 <li>Centre a 5 mm biopsy punch in the middle of the 10 mm circle and press firmly to create a hole to form a "donut"-like disc that will be used as a splint.</li>
 <li>Outline 10 mm circles on a transparent occlusive dressing such as Opsite and use scissors to create circular dressings.</li>
</ol>
2. Experimental Animals
<ol>
 <li>Obtain Animal Ethics Committee approval for all experiments that will be performed.</li>
 <li>Use 8-week old (22-26 grams) male C57BL/6J mice from a commercial breeder (e.g. The Jackson Laboratories).</li>
 <li>Keep mice in standard conditions of 21 &deg;C and a 12 hr light-dark cycle with free access to food and water.</li>
 <li>(Optional): Diabetes can be induced in 6 to 7 week old mice by a bolus intraperitoneal injection of 165 mg/kg streptozotocin (in citrate buffer, pH 4.5), with hyperglycemia confirmed by regular blood glucose monitoring (AccuChek glucometer). Diabetic mice may have polyuria and so their bedding may need to be changed more frequently to eliminate wetness and their weights should be monitored closely.</li>
</ol>
3. Anesthesia and Operative Preparation
<ol>
 <li>Induce general anesthesia using 5% isoflurane in 100% oxygen (flow rate 1 L/min) and maintain anesthesia using 1-3% isoflurane.</li>
 <li>Ensure the deep pedal reflexes of the mouse are suppressed and place the mouse in the prone position.</li>
 <li>Prepare the operative region by removing fur with clippers from the base of the neck to 3 cm further down the back and between the two shoulder blades.</li>
 <li>A light application of depilatory cream may be applied for no longer than 2 min. Wet gauze swabs can be used to ensure all cream and remaining fur is removed.</li>
 <li>Wipe the skin with an alcohol swab and two applications of 10% povidone-iodine (Betadine) and drape the mouse.</li>
</ol>
4. Excision and Splinting of Wound
<ol>
 <li>Diagrammatic representation of the murine wound-healing model is presented in Figure 1.</li>
 <li>Use a sterile 4 mm biopsy punch to outline two circular patterns for the wound on either side of the mouse's midline at the level of the shoulders (see Figures 2a-2b).</li>
 <li>Use serrated forceps to lift the skin in the middle of the outline and iris scissors to create a full-thickness wound that extends through the subcutaneous tissue (Figures 2c-2d), including the panniculus carnosus (Figure 2e), and excise the circular piece of tissue.</li>
 <li>Repeat the process for the wound on the other side of the midline (Figure 2f).</li>
 <li>Remove plastic protective coating from each side of the silicone splint.</li>
 <li>Apply cyanoacrylate adhesive (e.g. Super Glue or Krazy Glue) to one side of a silicone splint.</li>
 <li>Centre the splint over the wound (Figure 2g) and anchor the splint with interrupted 6-0 nylon sutures to ensure positioning (Figure 2h).</li>
 <li>Repeat the splinting process on the other wound.</li>
 <li>If required at this time-point, apply the therapeutic compound to be tested (up to 100 &mu;l) to one wound (Figure 2i), and the vehicle control to the other.</li>
 <li>Cover the wound with a transparent occlusive dressing (for example, OpSite) (Figure 2j-2k).</li>
 <li>A ruler is placed below the splints and a photomicrograph taken (Figure 2l).</li>
</ol>
6. Postoperative Management
<ol>
 <li>Carprofen (5 mg/kg) is administered once daily via sub-cutaneous injection for post-operative pain relief.</li>
 <li>After the surgery animals are individually caged and maintained on heat mats until fully recovered.</li>
 <li>Monitor animals twice daily for manifestations of pain and weight loss. We observed no gross behavioral displays of pain or weight loss.</li>
</ol>
7. Wound Measurement and Treatment
<ol>
 <li>The wound can be measured daily.</li>
 <li>Induce general anesthesia using 5% isoflurane gas (flow rate 1 L/min), and then ensure the deep sensory reflexes of the mouse are suppressed using 1-3% isoflurane.</li>
 <li>Gently peel back the occlusive dressing with forceps.</li>
 <li>Use surgical calipers to measure the wound diameter. We take the average of three measurements along the X, Y and Z axis (Figures 2m-2o) as well as a photomicrograph for future reference (Figure 2p).</li>
 <li>Optional: At this time the animal can be assessed for blood perfusion using a laser Doppler imager (Figure 2q).</li>
 <li>Re-application of the therapeutic compound and the vehicle control can be performed at this point.</li>
 <li>A clean transparent occlusive dressing is then re-applied and the animals kept warm until fully recovered.</li>
 <li>Note: if splints are not secured properly the wound will readily contract (Figure 2r).</li>
</ol>
8. Histological Analysis
<ol>
 <li>Euthanize the mice after 10 days with an overdose of anesthesia.</li>
 <li>Using forceps and a scalpel blade remove the sutures and carefully peel away the splint.</li>
 <li>Use iris scissors to create a wide, full excision around and under the wound area and incubate the tissue in 4% paraformaldehyde in phosphate buffered saline (PBS) at 4 &deg;C overnight.</li>
 <li>Transfer tissue to 17% sucrose in PBS solution for a further 24 hr at 4 &deg;C then remove excess solution by dabbing carefully on tissue and place in O.C.T compound and freeze at -80 &deg;C.</li>
 <li>Hematoxylin and eosin staining can be used to visualize the wound structure and epithelial gap. Neovascularisation can be assessed by immunohistochemical analyses to determine the number of capillaries (using Von Willebrand factor).</li>
</ol>

<ol>
	<li>Sen, C. K., 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+skin+wounds:+a+major+and+snowballing+threat+to+public+health+and+the+economy.">Human skin wounds: a major and snowballing threat to public health and the economy.</a> Wound Repair. 17, 763-771 (2009).</li><li>Sen, C. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Wound+healing+essentials:+let+there+be+oxygen.">Wound healing essentials: let there be oxygen.</a> Wound Repair Regen. 17, 1-18 (2009).</li><li>Gurtner, G. C., Werner, S., Barrandon, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Wound+repair+and+regeneration.">Wound repair and regeneration.</a> Nature. 453, 314-321 (2008).</li><li>Lindblad, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Considerations+for+selecting+the+correct+animal+model+for+dermal+wound-healing+studies.">Considerations for selecting the correct animal model for dermal wound-healing studies.</a> J. Biomater. Sci. Polym. Ed. 19, 1087-1096 (2008).</li><li>Grose, R., Werner, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Wound-healing+studies+in+transgenic+and+knockout+mice.">Wound-healing studies in transgenic and knockout mice.</a> Mol. Biotechnol. 28, 147-166 (2004).</li><li>Reid, R. R., Said, H. K., Mogford, J. E., Mustoe, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+future+of+wound+healing:+pursuing+surgical+models+in+transgenic+and+knockout+mice.">The future of wound healing: pursuing surgical models in transgenic and knockout mice.</a> J. Am. Coll. Surg. 199, 578-585 (2004).</li><li>Fang, R. C., Mustoe, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+of+wound+healing:+utility+in+transgenic+mice.">Animal models of wound healing: utility in transgenic mice.</a> J. Biomater. Sci. Polym. Ed. 19, 989-1005 (2008).</li><li>Wong, V. W., Sorkin, M., Glotzbach, J. P., Longaker, M. T., Gurtner, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgical+approaches+to+create+murine+models+of+human+wound+healing.">Surgical approaches to create murine models of human wound healing.</a> J. Biomed. Biotechnol. 2011, 969618 (2011).</li><li>Galiano, R. D., Michaels, J. t., Dobryansky, M., Levine, J. P., Gurtner, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+and+reproducible+murine+model+of+excisional+wound+healing.">Quantitative and reproducible murine model of excisional wound healing.</a> Wound Repair. 12, 485-492 (2004).</li><li>Galiano, R. D., 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=Topical+vascular+endothelial+growth+factor+accelerates+diabetic+wound+healing+through+increased+angiogenesis+and+by+mobilizing+and+recruiting+bone+marrow-derived+cells.">Topical vascular endothelial growth factor accelerates diabetic wound healing through increased angiogenesis and by mobilizing and recruiting bone marrow-derived cells.</a> The American Journal of Pathology. 164, 1935-1947 (2004).</li><li>Thangarajah, 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=The+molecular+basis+for+impaired+hypoxia-induced+VEGF+expression+in+diabetic+tissues.">The molecular basis for impaired hypoxia-induced VEGF expression in diabetic tissues.</a> Proceedings of the National Academy of Sciences of the United States of America. 106, 13505-13510 (2009).</li><li>Raza, A., Bayles, C., Biebel, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+of+Bacterial+Growth+and+Moisture+Handling+Properties+of+Transparent+Dressings:+3M+Tegaderm+Transparent+Dressing,+3M+Tegaderm+HP+Transparent+Dressing,+and+Opsite+IV3000+Transparent+Dressing.">Investigation of Bacterial Growth and Moisture Handling Properties of Transparent Dressings: 3M Tegaderm Transparent Dressing, 3M Tegaderm HP Transparent Dressing, and Opsite IV3000 Transparent Dressing.</a> Smith and Nephew Report. , (1998).</li><li>Chung, T. Y., Peplow, P. V., Baxter, G. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testing+photobiomodulatory+effects+of+laser+irradiation+on+wound+healing:+development+of+an+improved+model+for+dressing+wounds+in+mice.">Testing photobiomodulatory effects of laser irradiation on wound healing: development of an improved model for dressing wounds in mice.</a> Photomed. Laser Surg. 28, 589-596 (2010).</li></ol>

The authors have nothing to disclose.

This is an experimental murine model of cutaneous wound healing. A significant feature of this model is the use of silicone splints to prevent wound contraction so that re-epithelialization and new tissue formation may occur, making it similar to the process that occurs in humans. This model is versatile and can be used to assess wound healing in both physiological and pathophysiological (e.g. diabetes mellitus) settings. The model may also be used to assess potential wound healing or angiogenesis therapeutics i...

Impaired wound healing is responsible for significant morbidity and mortality worldwide; this is particularly true for sufferers of diabetes mellitus1,2. In humans, wound healing is a continuum of processes, in which there is significant overlapping3. Immediately following wounding, inflammatory processes are initiated. Inflammatory cells release factors that encourage the processes of cell proliferation, migration and angiogenesis. After re-epithelialization and new tissue formation there is a phase of remodeling that entails both apoptosis and re-organization of matrix proteins such as collagen.
The complexity of wound healing cannot currently be replicated in vitro and this necessitates the use of animal models. To date, wound-healing studies have been limited to large animal models, such as swine, to ensure that the healing processes are equivalent and comparable to humans. However, using large animals for such studies can be difficult to house and are not always practical4. The laboratory mouse represents an economical animal model that can be easily genetically manipulated for mechanistic investigation5-7. However, murine wounds heal differently to human&#x2019;s, primarily due to the process of contraction8. This is in part, due to an extensive subcutaneous striated muscle layer called the panniculus carnosus that is largely absent in humans. In mice, this muscle layer allows the skin to move independently of the deeper muscles and is responsible for the rapid contraction of skin following wounding.
To overcome this limitation, murine wound healing can be adapted to replicate human wound healing by use of a splint (Figure 1)8,9. In this video we demonstrate the splinted murine wound model that eliminates wound contraction and more closely approximates the human processes of re-epithelialization and new tissue formation. In this model two full-thickness excisions that include the panniculus carnosus are created on the dorsum, one on each side of the midline of the mouse. A silicone splint is placed around the wound with the assistance of adhesive and the splint then secured with interrupted sutures. Each mouse acts as its own control, with one wound receiving treatment and the other vehicle control, thereby reducing animal numbers. Following topical applications, a transparent occlusive dressing is applied. The dressing can be removed when required for further topical applications and/or measurement of the wound area10,11. At the completion of experiments, wound closure, morphological architecture and degree of neovascularization can be assessed by immunohistochemistry. This economical and easy to perform model can also be utilized to assess wound healing in the context of diabetes mellitus or other pathophysiologies.

<table border="0">
<tbody>
 <tr>
 <td>Name of Reagent/Material</td>
 <td>Company</td>
 <td>Catalog Number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Press-to-seal silicone sheeting 0.5 mm thick</td>
 <td>Invitrogen</td>
 <td>P18178</td>
 <td>Cut into "donuts" with external diameter of 1cm external, 0.5 cm internal diameter</td>
 </tr>
 <tr>
 <td>Biopsy punch 5 mm</td>
 <td>Steifel</td>
 <td>BC-B1-0500</td>
 <td>To outline wound area to be excised</td>
 </tr>
 <tr>
 <td>Vannas scissors 8.5 cm curved</td>
 <td>World Precision Instruments </td>
 <td>501232</td>
 <td>For wound incision and excision</td>
 </tr>
 <tr>
 <td>Dumonte #7b forceps, 11 cm</td>
 <td>World Precision Instruments</td>
 <td>501302</td>
 <td>To grip skin when creating incision and excising skin </td>
 </tr>
 <tr>
 <td>Graefe forceps, serrated 10cm</td>
 <td>World Precision Instruments</td>
 <td>14142</td>
 <td>To help attach silicone splint to skin</td>
 </tr>
 <tr>
 <td>Needle holder, smooth jaws, curved, 12.5 cm</td>
 <td>World Precision Instruments</td>
 <td>14132</td>
 <td></td>
 </tr>
 <tr>
 <td>Malis forceps, smooth, straight, 12 cm</td>
 <td>Codman and Shurtleff, Inc (J&amp;J)</td>
 <td>80-1500</td>
 <td>To suture the silicon rings to the skin</td>
 </tr>
 <tr>
 <td>Ruler, 0.5 mm gradation</td>
 <td>n/a</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Calipers 0.25 mm gradation</td>
 <td>Duckworth and Kent</td>
 <td>9-653</td>
 <td>To measure wound area</td>
 </tr>
 <tr>
 <td>Opsite FlexiFix transparent adhesive film. 10 cm x 1 m</td>
 <td>Smith &amp; Nephew</td>
 <td>66030570</td>
 <td></td>
 </tr>
 <tr>
 <td>Rimadyl (Carprofen)</td>
 <td>Pfizer</td>
 <td>462986</td>
 <td></td>
 </tr>
 </tbody>
</table>

murine model of wound healing

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. Impaired wound healing, which occurs in diabetic patients for example, can lead to severe unfavorable outcomes such as amputation. There is, therefore, an increasing impetus to develop novel agents that promote wound repair. The testing of these has been limited to large animal models such as swine, which are often impractical. Mice represent the ideal preclinical model, as they are economical and amenable to genetic manipulation, which allows for mechanistic investigation. However, wound healing in a mouse is fundamentally different to that of humans as it primarily occurs via contraction. Our murine model overcomes this by incorporating a splint around the wound. By splinting the wound, the repair process is then dependent on epithelialization, cellular proliferation and angiogenesis, which closely mirror the biological processes of human wound healing. Whilst requiring consistency and care, this murine model does not involve complicated surgical techniques and allows for the robust testing of promising agents that may, for example, promote angiogenesis or inhibit inflammation. Furthermore, each mouse acts as its own control as two wounds are prepared, enabling the application of both the test compound and the vehicle control on the same animal. In conclusion, we demonstrate a practical, easy-to-learn, and robust model of wound healing, which is comparable to that of humans.

A wound closure curve is determined by calculating the average diameter of the wound and expressing the results as a percentage, i.e. 100 - (Day 0 diameter/Day X diameter). In this experiment a therapeutic compound (or vehicle control) was applied daily to the wound. The therapeutic compound greatly accelerated wound closure (Figure 3). It is important to note that the splints must be maintained for the duration of the experiment, as removal of splints will lead to rapid wound contraction (<stro...

Watch this Scientific Journal Video about Murine Model of Wound Healing at JoVE.com

Murine Model of Wound Healing

A murine model of cutaneous wound healing that can be used to assess therapeutic compounds in physiological and pathophysiological settings.

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. ...

Research

JoVE Journal

Medicine

63.5K Views.  The Heart Research Institute. A murine model of cutaneous wound healing that can be used to assess therapeutic compounds in physiological and pathophysiological settings.

Video: Murine Model of Wound Healing

Murine Endoscopy for In Vivo Multimodal Imaging of Carcinogenesis and Assessment of Intestinal Wound Healing and Inflammation

Mouse models are widely used to study pathogenesis of human diseases and to evaluate diagnostic procedures as well as therapeutic interventions preclinically. However, valid assessment of pathological alterations often requires histological analysis, and when performed ex vivo, necessitates death of the animal. Therefore in conventional experimental settings, intra-individual follow-up examinations are rarely possible. Thus, development of murine endoscopy in live mice enables investigators for the first time to both directly visualize the gastrointestinal mucosa and also repeat the procedure to monitor for alterations. Numerous applications for in vivo murine endoscopy exist, including studying intestinal inflammation or wound healing, obtaining mucosal biopsies repeatedly, and to locally administer diagnostic or therapeutic agents using miniature injection catheters. Most recently, molecular imaging has extended diagnostic imaging modalities allowing specific detection of distinct target molecules using specific photoprobes. In conclusion, murine endoscopy has emerged as a novel cutting-edge technology for diagnostic experimental in vivo imaging and may significantly impact on preclinical research in various fields.

Murine Endoscopy for In Vivo Multimodal Imaging of Carcinogenesis and Assessment of Intestinal Wound Healing and Inflammation

Small animal imaging techniques allow serial diagnostic examinations and therapeutic interventions in vivo. Recently, the scope of applications has significantly widened and currently includes assessment of colonic tumor development, wound healing and monitoring of inflammation. This protocol illustrates these diverse potential applications of murine endoscopy.

Mouse models are widely used to study pathogenesis of human diseases and to evaluate diagnostic procedures as well as therapeutic interventions ...

A Mouse Fetal Skin Model of Scarless Wound Repair

Early in utero, but not in postnatal life, cutaneous wounds undergo regeneration and heal without formation of a scar. Scarless fetal wound healing occurs across species but is age dependent. The transition from a scarless to scarring phenotype occurs in the third trimester of pregnancy in humans and around embryonic day 18 (E18) in mice. However, this varies with the size of the wound with larger defects generating a scar at an earlier gestational age. The emergence of lineage tracing and other genetic tools in the mouse has opened promising new avenues for investigation of fetal scarless wound healing. However, given the inherently high rates of morbidity and premature uterine contraction associated with fetal surgery, investigations of fetal scarless wound healing in vivo require a precise and reproducible surgical model. Here we detail a reliable model of fetal scarless wound healing in the dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.

During mammalian development, early gestational skin wounds heal without a scar. Here we detail a reliable and reproducible model of fetal scarless wound healing in the cutaneous dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.

Early in utero, but not in postnatal life, cutaneous wounds undergo regeneration and heal without formation of a scar. Scarless fetal wound healing occurs ...

Demonstration of the Rat Ischemic Skin Wound Model

The propensity for chronic wounds in humans increases with ageing, disease conditions such as diabetes and impaired cardiovascular function, and unrelieved pressure due to immobility. Animal models have been developed that attempt to mimic these conditions for the purpose of furthering our understanding of the complexity of chronic wounds. The model described herein is a rat ischemic skin flap model that permits a prolonged reduction of blood flow resulting in wounds that become ischemic and resemble a chronic wound phenotype (reduced vascularization, increased inflammation and delayed wound closure). It consists of a bipedicled dorsal flap with 2 ischemic wounds placed centrally and 2 non-ischemic wounds lateral to the flap as controls. A novel addition to this ischemic skin flap model is the placement of a silicone sheet beneath the flap that functions as a barrier and a splint to prevent revascularization and reduce contraction as the wounds heal. Despite the debate of using rats for wound healing studies due to their quite distinct anatomic and physiologic differences compared to humans (i.e., the presence of a panniculus carnosus muscle, short life-span, increased number of hair follicles, and their ability to heal infected wounds) the modifications employed in this model make it a valuable alternative to previously developed ischemic skin flap models.

The rat, due to its size, availability, and rather docile behavior, has been utilized as a research model for many years. The goal of this protocol is to utilize the rat as an ischemic skin wound healing model to provide valuable insight into the pathophysiology of chronic wounds.

The propensity for chronic wounds in humans increases with ageing, disease conditions such as diabetes and impaired cardiovascular function, and ...

Multimodal Quantitative Phase Imaging with Digital Holographic Microscopy Accurately Assesses Intestinal Inflammation and Epithelial Wound Healing

The incidence of inflammatory bowel disease, i.e., Crohn&#39;s disease and Ulcerative colitis, has significantly increased over the last decade. The etiology of IBD remains unknown and current therapeutic strategies are based on the unspecific suppression of the immune system. The development of treatments that specifically target intestinal inflammation and epithelial wound healing could significantly improve management of IBD, however this requires accurate detection of inflammatory changes. Currently, potential drug candidates are usually evaluated using animal models in vivo or with cell culture based techniques in vitro. Histological examination usually requires the cells or tissues of interest to be stained, which may alter the sample characteristics and furthermore, the interpretation of findings can vary by investigator expertise. Digital holographic microscopy (DHM), based on the detection of optical path length delay, allows stain-free quantitative phase contrast imaging. This allows the results to be directly correlated with absolute biophysical parameters. We demonstrate how measurement of changes in tissue density with DHM, based on refractive index measurement, can quantify inflammatory alterations, without staining, in different layers of colonic tissue specimens from mice and humans with colitis. Additionally, we demonstrate continuous multimodal label-free monitoring of epithelial wound healing in vitro, possible using DHM through the simple automated determination of the wounded area and simultaneous determination of morphological parameters such as dry mass and layer thickness of migrating cells. In conclusion, DHM represents a valuable, novel and quantitative tool for the assessment of intestinal inflammation with absolute values for parameters possible, simplified quantification of epithelial wound healing in vitro and therefore has high potential for translational diagnostic use.

Accurate assessment of anti-inflammatory effects is of utmost importance for the evaluation of potential new drugs for the treatment of inflammatory bowel disease. Digital holographic microscopy provides assessment of inflammation in murine and human colonic tissue samples as well as automated multimodal evaluation of epithelial wound healing in vitro.

The incidence of inflammatory bowel disease, i.e., Crohn&#39;s disease and Ulcerative colitis, has significantly increased over the last decade. The ...

Creation and Transplantation of an Adipose-derived Stem Cell (ASC) Sheet in a Diabetic Wound-healing Model

Artificial skin has achieved considerable therapeutic results in clinical practice. However, artificial skin treatments for wounds in diabetic patients with impeded blood flow or with large wounds might be prolonged. Cell-based therapies have appeared as a new technique for the treatment of diabetic ulcers, and cell-sheet engineering has improved the efficacy of cell transplantation. A number of reports have suggested that adipose-derived stem cells (ASCs), a type of mesenchymal stromal cell (MSC), exhibit therapeutic potential due to their relative abundance in adipose tissue and their accessibility for collection when compared to MSCs from other tissues. Therefore, ASCs appear to be a good source of stem cells for therapeutic use. In this study, ASC sheets from the epididymal adipose fat of normal Lewis rats were successfully created using temperature-responsive culture dishes and normal culture medium containing ascorbic acid. The ASC sheets were transplanted into Zucker diabetic fatty (ZDF) rats, a rat model of type 2 diabetes and obesity, that exhibit diminished wound healing. A wound was created on the posterior cranial surface, ASC sheets were transplanted into the wound, and a bilayer artificial skin was used to cover the sheets. ZDF rats that received ASC sheets had better wound healing than ZDF rats without the transplantation of ASC sheets. This approach was limited because ASC sheets are sensitive to dry conditions, requiring the maintenance of a moist wound environment. Therefore, artificial skin was used to cover the ASC sheet to prevent drying. The allogenic transplantation of ASC sheets in combination with artificial skin might also be applicable to other intractable ulcers or burns, such as those observed with peripheral arterial disease and collagen disease, and might be administered to patients who are undernourished or are using steroids. Thus, this treatment might be the first step towards improving the therapeutic options for diabetic wound healing.

Creation and Transplantation of an Adipose-derived Stem Cell ASC Sheet in a Diabetic Wound-healing Model

Adipose-derived stem cells (ASCs) are easily isolated and harvested from the fat of normal rats. ASC sheets can be created using cell-sheet engineering and can be transplanted into Zucker diabetic fatty rats exhibiting full-thickness skin defects with exposed bone and then covered with a bilayer of artificial skin.

Artificial skin has achieved considerable therapeutic results in clinical practice. However, artificial skin treatments for wounds in diabetic patients ...

Development of a Direct Pulp-capping Model for the Evaluation of Pulpal Wound Healing and Reparative Dentin Formation in Mice

Dental pulp is a vital organ of a tooth fully protected by enamel and dentin. When the pulp is exposed due to cariogenic or iatrogenic injuries, it is often capped with biocompatible materials in order to expedite pulpal wound healing. The ultimate goal is to regenerate reparative dentin, a physical barrier that functions as a "biological seal" and protects the underlying pulp tissue. Although this direct pulp-capping procedure has long been used in dentistry, the underlying molecular mechanism of pulpal wound healing and reparative dentin formation is still poorly understood. To induce reparative dentin, pulp capping has been performed experimentally in large animals, but less so in mice, presumably due to their small sizes and the ensuing technical difficulties. Here, we present a detailed, step-by-step method of performing a pulp-capping procedure in mice, including the preparation of a Class-I-like cavity, the placement of pulp-capping materials, and the restoration procedure using dental composite. Our pulp-capping mouse model will be instrumental in investigating the fundamental molecular mechanisms of pulpal wound healing in the context of reparative dentin in vivo by enabling the use of transgenic or knockout mice that are widely available in the research community.

We describe a step-by-step method of performing direct pulp capping on mice teeth for the evaluation of pulpal wound healing and reparative dentin formation in vivo.

Dental pulp is a vital organ of a tooth fully protected by enamel and dentin. When the pulp is exposed due to cariogenic or iatrogenic injuries, it is ...

Microscopy Based Methods for the Assessment of Epithelial Cell Migration During In Vitro Wound Healing

Cell migration is a mandatory aspect for wound healing. Creating artificial wounds on research animal models often results in costly and complicated experimental procedures, while potentially lacking in precision. In vitro culture of epithelial cell lines provides a suitable platform for researching the cell migratory behavior in wound healing and the impact of treatments on these cells. The physiology of epithelial cells is often studied in non-confluent conditions; however, this approach may not resemble natural wound healing conditions. Disrupting the epithelium integrity by mechanical means generates a realistic model, but may impede the application of molecular techniques. Consequently, microscopy based techniques are optimal for studying epithelial cell migration in vitro. Here we detail two specific methods, the artificial wound scratch assay and the artificial migration front assay, that can obtain quantitative and qualitative data, respectively, on the migratory performance of epithelial cells.

Microscopy Based Methods for the Assessment of Epithelial Cell Migration During  In Vitro Wound Healing

This manuscript describes how incision-like lesions made on cultured epithelial cell monolayers conveniently model wound healing in vitro, allowing for imaging by confocal or laser scanning microscopy, and which can provide high-quality quantitative and qualitative data for studying both cell behavior and the mechanisms involved in migration.

Cell migration is a mandatory aspect for wound healing. Creating artificial wounds on research animal models often results in costly and complicated ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

Corneal Epithelial Abrasion with Ocular Burr As a Model for Cornea Wound Healing

The murine cornea provides an excellent model to study wound healing. The cornea is the outermost layer of the eye, and thus is the first defense to injury. In fact, the most common type of eye injury found in clinic is a corneal abrasion. Here, we utilize an ocular burr to induce an abrasion resulting in removal of the corneal epithelium in vivo on anesthetized mice. This method allows for targeted and reproducible epithelial disruption, leaving other areas intact. In addition, we describe the visualization of the abraded epithelium with fluorescein staining and provide concrete advice on how to visualize the abraded cornea. Then, we follow the timeline of wound healing 0, 18, and 72 h after abrasion, until the wound is re-epithelialized. The epithelial abrasion model of corneal injury is ideal for studies on epithelial cell proliferation, migration and re-epithelialization of the corneal layers. However, this method is not optimal to study stromal activation during wound healing, because the ocular burr does not penetrate to the stromal cell layers. This method is also suitable for clinical applications, for example, pre-clinical test of drug effectiveness.

This protocol describes a method to inflict an abrasion to the ocular surface of the mouse, and to follow the wound healing process thereafter. The protocol takes advantage of an ocular burr to partially remove the surface epithelium of the eye in anaesthetized mice.

The murine cornea provides an excellent model to study wound healing. The cornea is the outermost layer of the eye, and thus is the first defense to ...

Ex Vivo Corneal Organ Culture Model for Wound Healing Studies

The cornea has been used extensively as a model system to study wound healing. The ability to generate and utilize primary mammalian cells in two dimensional (2D) and three dimensional (3D) culture has generated a wealth of information not only about corneal biology but also about wound healing, myofibroblast biology, and scarring in general. The goal of the protocol is an assay system for quantifying myofibroblast development, which characterizes scarring. We demonstrate a corneal organ culture ex vivo model using pig eyes. In this anterior keratectomy wound, corneas still in the globe are wounded with a circular blade called a trephine. A plug of approximately 1/3 of the anterior cornea is removed including the epithelium, the basement membrane, and the anterior part of the stroma. After wounding, corneas are cut from the globe, mounted on a collagen/agar base, and cultured for two weeks in supplemented-serum free medium with stabilized vitamin C to augment cell proliferation and extracellular matrix secretion by resident fibroblasts. Activation of myofibroblasts in the anterior stroma is evident in the healed cornea. This model can be used to assay wound closure, the development of myofibroblasts and fibrotic markers, and for toxicology studies. In addition, the effects of small molecule inhibitors as well as lipid-mediated siRNA transfection for gene knockdown can be tested in this system.

A protocol for an ex vivo corneal organ culture model useful for wound healing studies is described. This model system can be used to assess the effects of agents to promote regenerative healing or drug toxicity in an organized 3D multicellular environment.