This work was supported by grant from the Ministry of Science and Technology (MOST 103-2633-B-002-002; 104-2320-B-002-048). We thank Drs. Betty Wu-Hsieh and Chien-Kuo Lee at NTU, Leigh Zerboni at Stanford University and Dr. Peter Hoffmann at the University of Hawaii for reading the manuscript, Yun Chien at NTU for technical assistance, and Dr. Wen-Chi Wei at Agriculture Biotechnology Research Center at Academia Sinica for technical advice.

Female mice at 8 - 12 weeks of age were used for this study. C57/BL6 wild-type (WT) and IL-15 deficient (Il15-/-) mice were purchased from National Laboratory Animal Center (NLAC), Taiwan and Taconic Farm, respectively. IL-15-deficient (Il15-/-) andIL-15-dominant (Il15+/- and Il15+/+) showed a 1:3 ratio in the second generation from the cross of Il15+/- heterozygotes. The genotype of Il15-/- mice was confirmed by PCR analysis. Mice were maintained in the Sp...

<ol>
	<li>Effendy, I., Loffler, H., Maibach, H. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidermal+cytokines+in+murine+cutaneous+irritant+responses.">Epidermal cytokines in murine cutaneous irritant responses.</a> Journal of applied toxicology : JAT. 20, 335-341 (2000).</li><li>Nestle, F. O., Di Meglio, P., Qin, J. Z., Nickoloff, B. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Skin+immune+sentinels+in+health+and+disease.">Skin immune sentinels in health and disease.</a> Nature reviews. 9, 679-691 (2009).</li><li>Liu, L. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Topical+application+of+HIV+DNA+vaccine+with+cytokine-expression+plasmids+induces+strong+antigen-specific+immune+responses.">Topical application of HIV DNA vaccine with cytokine-expression plasmids induces strong antigen-specific immune responses.</a> Vaccine. 20, 42-48 (2001).</li><li>Lu, B., Federoff, H. J., Wang, Y., Goldsmith, L. A., Scott, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Topical+application+of+viral+vectors+for+epidermal+gene+transfer.">Topical application of viral vectors for epidermal gene transfer.</a> J Invest Dermatol. 108, 803-808 (1997).</li><li>Partidos, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Delivering+vaccines+into+the+skin+without+needles+and+syringes.">Delivering vaccines into the skin without needles and syringes.</a> Expert Rev Vaccines. 2, 753-761 (2003).</li><li>Peachman, K. K., Rao, M., Alving, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunization+with+DNA+through+the+skin.">Immunization with DNA through the skin.</a> Methods. 31, 232-242 (2003).</li><li>Yang, N. S., Burkholder, J., Roberts, B., Martinell, B., McCabe, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+and+in+vitro+gene+transfer+to+mammalian+somatic+cells+by+particle+bombardment.">In vivo and in vitro gene transfer to mammalian somatic cells by particle bombardment.</a> Proc Natl Acad Sci U S A. 87, 9568-9572 (1990).</li><li>Tang, D. C., DeVit, M., Johnston, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+immunization+is+a+simple+method+for+eliciting+an+immune+response.">Genetic immunization is a simple method for eliciting an immune response.</a> Nature. 356, 152-154 (1992).</li><li>Haynes, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Particle-mediated+DNA+vaccine+delivery+to+the+skin.">Particle-mediated DNA vaccine delivery to the skin.</a> Expert Opin Biol Ther. 4, 889-900 (2004).</li><li>Tuomela, 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=Biodistribution+and+general+safety+of+a+naked+DNA+plasmid,+GTU-MultiHIV,+in+a+rat,+using+a+quantitative+PCR+method.">Biodistribution and general safety of a naked DNA plasmid, GTU-MultiHIV, in a rat, using a quantitative PCR method.</a> Vaccine. 23, 890-896 (2005).</li><li>Eriksson, E., 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=In+vivo+gene+transfer+to+skin+and+wound+by+microseeding.">In vivo gene transfer to skin and wound by microseeding.</a> J Surg Res. 78, 85-91 (1998).</li><li>Lee, T. 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=An+alternatively+spliced+IL-15+isoform+modulates+abrasion-induced+keratinocyte+activation.">An alternatively spliced IL-15 isoform modulates abrasion-induced keratinocyte activation.</a> J Invest Dermatol. 135, 1329-1337 (2015).</li><li>Rudy, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imiquimod+(Aldara):+modifying+the+immune+response.">Imiquimod (Aldara): modifying the immune response.</a> Dermatol Nurs. 14, 268-270 (2002).</li><li>van der Fits, 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=Imiquimod-induced+psoriasis-like+skin+inflammation+in+mice+is+mediated+via+the+IL-23/IL-17+axis.">Imiquimod-induced psoriasis-like skin inflammation in mice is mediated via the IL-23/IL-17 axis.</a> J Immunol. 182, 5836-5845 (2009).</li><li>Sumida, 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=Interplay+between+CXCR2+and+BLT1+facilitates+neutrophil+infiltration+and+resultant+keratinocyte+activation+in+a+murine+model+of+imiquimod-induced+psoriasis.">Interplay between CXCR2 and BLT1 facilitates neutrophil infiltration and resultant keratinocyte activation in a murine model of imiquimod-induced psoriasis.</a> J Immunol. 192, 4361-4369 (2014).</li><li>Bamford, R. N., DeFilippis, A. P., Azimi, N., Kurys, G., Waldmann, 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+5'+untranslated+region,+signal+peptide,+and+the+coding+sequence+of+the+carboxyl+terminus+of+IL-15+participate+in+its+multifaceted+translational+control.">The 5' untranslated region, signal peptide, and the coding sequence of the carboxyl terminus of IL-15 participate in its multifaceted translational control.</a> J Immunol. 160, 4418-4426 (1998).</li><li>Horton, R. M., Hunt, H. D., Ho, S. N., Pullen, J. K., Pease, L. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+hybrid+genes+without+the+use+of+restriction+enzymes:+gene+splicing+by+overlap+extension.">Engineering hybrid genes without the use of restriction enzymes: gene splicing by overlap extension.</a> Gene. 77, 61-68 (1989).</li><li>Tan, X., Lefrancois, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+IL-15+isoforms+generated+by+alternative+splicing+are+expressed+in+the+intestinal+epithelium.">Novel IL-15 isoforms generated by alternative splicing are expressed in the intestinal epithelium.</a> Genes Immun. 7, 407-416 (2006).</li><li>Basner-Tschakarjan, E., Mirmohammadsadegh, A., Baer, A., Hengge, U. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uptake+and+trafficking+of+DNA+in+keratinocytes:+evidence+for+DNA-binding+proteins.">Uptake and trafficking of DNA in keratinocytes: evidence for DNA-binding proteins.</a> Gene Ther. 11, 765-774 (2004).</li><li>Fan, H., Lin, Q., Morrissey, G. R., Khavari, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunization+via+hair+follicles+by+topical+application+of+naked+DNA+to+normal+skin.">Immunization via hair follicles by topical application of naked DNA to normal skin.</a> Nat Biotechnol. 17, 870-872 (1999).</li><li>Kennedy-Crispin, 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=Human+keratinocytes'+response+to+injury+upregulates+CCL20+and+other+genes+linking+innate+and+adaptive+immunity.">Human keratinocytes' response to injury upregulates CCL20 and other genes linking innate and adaptive immunity.</a> J Invest Dermatol. 132, 105-113 (2012).</li></ol>

The authors have no financial interests to disclose.

The most critical step to ensure the expression of the acufected plasmid DNA is to evenly oscillate and loosen the horny layer of the skin. While pushing the needles gently without cutting the skin, the force should be hard enough to depress the surface. To facilitate absorption of DNA in 10 &#956;L solution on a 1 cm x 1 cm surface area, the needles should oscillate up-and-down for about 100 times in 30 s. One can determine the force that needs to prick the skin and by noting the number of times that is needed to yield ...

Skin is the first-line of host defense. Keratinocytes (KCs) are the major cell type in the skin of humans and mice. In response to environmental stimuli (e.g. sunlight, oxygen, chemicals and pathogenic invasion), KCs are activated and produce a wide array of proinflammatory cytokines and chemokines such as IL-8, IL-6, IL-1&#945;, IL-1&#946;, TNF-&#945; and GM-CSF1. Together they trigger the recruitment of immune cells to the skin. Aggravated cutaneous inflammation is often associated with numerous human diseases including acute ectopic contact dermatitis and chronic T cell-mediated inflammation (e.g. allergic contact dermatitis and psoriasis)2. Modulating proinflammatory responses in the skin by inhibiting KC activation is a plausible approach to treat cutaneous inflammation. This protocol describes a new approach to transiently express a cytokine gene in the epidermis in order to study immune response consequential to such a treatment in the skin.
The epidermis composes the most superficial layer of the skin. It serves as a physical barrier keeping external substances such as nucleic acids and pathogens from entering the deeper layers of the skin. Several needle-free techniques have been established for epidermal DNA transfer3,4. DNA in solution or associated with cationic liposomes or adenovirus vectors has been directly applied to the epidermis modified with techniques such as the removal of the stratum corneum or the treatment with depilating reagent. Removal of the cornified epithelium facilitates DNA crossing the epidermal barrier and interaction with keratinocytes and Langerhans cells to induce immune responses5. While a large surface area is available for DNA transfer and this approach does not involve needles, there are disadvantages including the requirement for the large quantities of DNA (10 - 100 &#956;g), harsh treatment on the skin by stripping, and the inconsistent results in inducing immune response in the immunized animals without DNA delivery booster6. Microparticle-mediated intracellular delivery of naked DNA to the skin has been shown to be highly efficient and reproducible for inducing immune response7,8. A hand-held gene gun has been used to bombard the skin target site with plasmid DNA-coated gold particles 2 &#956;m-diameter in size by means of pressurized helium air flow9. The plasmid DNA is presumably taken up by KCsand dendritic cells (DCs) in the skin and the protein is locally expressed or being transported to draining lymph nodes by DCs10. Although the gene gun system is simple and requires limited technical experience, the cost for preparing and delivering the &#34;DNA bullet&#34; (i.e. gold powders, helium gas) and for the gene gun itself has limited its general application. In addition, the requirement for a helium gas delivery system limits the ease of gene gun transport when the experiments are conducted at different locations. Microseeding has been demonstrated to achieve a higher efficiency of gene transfer than single injection and particle bombardment11. Microseeding uses a tattoo gun to deliver DNA to the skin without the use of particle beads11. Oscillating the microneedles on the skin using this approach is likely to directly scrape the cell membrane and thus transfer DNA to multiple cells at the same time. However, pain associated with the large number of injections with 0.254 mm-diameter needles is a disadvantage.
Here we provide an alternative approach to DNA delivery in vivo. The &#34;acufection&#34; protocol we described here provides an economical and efficient way to deliver plasmid DNA in mouse skin. Briefly, ten acupuncture needles (0.2 mm in diameter x 13 mm in length) were bound in a bundle by adhesive tape. A volume of 10 &#956;L of PBS with 10 &#956;g of plasmid DNA containing the transgene of interest was placed on the shaved, depilatory cream-treated flank skin. By using the acupuncture needle bundle to oscillate the surface (1 cm x 1 cm) of the skin, the keratins at the horny layer were loosened and the plasmid DNA applied to the surface was absorbed into the epidermis. Skin damage was monitored and found to be minimal. Expression of the transfected gene in the acufected skin was confirmed by both quantitative real-time PCR (qRT-PCR) and ELISA. The immune modulatory effects of acufection-delivered IL-15&#916;E7 on cutaneous inflammation were demonstrated using the IMQ-treated mouse model12. While acufection proves to be an easy and less demanding method for DNA delivery in vivo, the optimal amount of DNA for different genes and the times to prick the skin have to be carefully optimized to obtain reproducible results.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Accu Handy Needle</td>
			<td>Accu</td>
			<td>36Gx0.5</td>
			<td>Medical device</td>
		</tr>
		<tr>
			<td>NairTM Lotion</td>
			<td>Church &#38; Dwight</td>
			<td>N/A</td>
			<td>Use to remove hair</td>
		</tr>
		<tr>
			<td>Shandon Xyline substitute</td>
			<td>Thermo Fisher Scientific</td>
			<td>6764506</td>
			<td>Deparaffinization</td>
		</tr>
		<tr>
			<td>Avertin (2,2,2-Tribromethanol)</td>
			<td>Sigma-Aldrich</td>
			<td>T4,840-2</td>
			<td>Anesthesia</td>
		</tr>
		<tr>
			<td>2-methyl-2-butanol</td>
			<td>Sigma-Aldrich</td>
			<td>152463</td>
			<td>Solvent for the dissolution of avertin</td>
		</tr>
		<tr>
			<td>DifcoTM LB broth, Miller</td>
			<td>BD</td>
			<td>244620</td>
			<td>Propagation and maintenance of E. coli for molecular biology</td>
		</tr>
		<tr>
			<td>QIAGEN&#9415; Plasmid Midi Kit</td>
			<td>QIAGEN</td>
			<td>12143</td>
			<td>Purification of plasmid DNA from E. coli</td>
		</tr>
		<tr>
			<td>Mouse IL-15/IL-15R Complex ELISA Ready-SET-Go kit</td>
			<td>eBioscience</td>
			<td>88-7215</td>
			<td>Measure IL-15 protein</td>
		</tr>
		<tr>
			<td>Anti-mouse Ly6G</td>
			<td>BioLegend</td>
			<td>127601</td>
			<td>Antibody used for immunohistochemical stain</td>
		</tr>
		<tr>
			<td>anti-mouse Ki-67</td>
			<td>eBioscience</td>
			<td>14-5698-80</td>
			<td>Antibody used for immunohistochemical stain</td>
		</tr>
		<tr>
			<td>Simple Stain Mouse MAXPO (Rat)</td>
			<td>Nichirei Biosciences</td>
			<td>414341F</td>
			<td>Reagent to block background signal in mouse-on-mouse stain</td>
		</tr>
		<tr>
			<td>DAB Peroxidase (HRP) Substrate Kit</td>
			<td>Vector Laboratories</td>
			<td>SK-4100</td>
			<td>Peroxidse substrate for immunohistochemical stain</td>
		</tr>
		<tr>
			<td>Ultra V block</td>
			<td>Thermo Fisher Scientific</td>
			<td>TA-060-UB</td>
			<td>Reduce nonspecific background staining</td>
		</tr>
		<tr>
			<td>Methyl green</td>
			<td>Sigma-Aldrich</td>
			<td>M8884</td>
			<td>Nuclear staining</td>
		</tr>
		<tr>
			<td>Vecta MountTM</td>
			<td>Vector Laboratories</td>
			<td>M-5000</td>
			<td>Permanently preserving histochemical stains</td>
		</tr>
		<tr>
			<td>Protease inhibitor cocktail tablets</td>
			<td>Roche</td>
			<td>04-693-116-001</td>
			<td>Inhibit protease activity in cell lysate</td>
		</tr>
		<tr>
			<td>Aldara cream</td>
			<td>3M Parmaceuticals</td>
			<td>N/A</td>
			<td>5% imiquimod cream</td>
		</tr>
		<tr>
			<td>Bessman Tissue Pulverizer</td>
			<td>Spectrum Labs</td>
			<td>189475</td>
			<td>Use to pulverize skin tissue</td>
		</tr>
		<tr>
			<td>ABI7900HT cycler</td>
			<td>Thermo Fisher Scientific</td>
			<td>N/A</td>
			<td>quantitative real-time PCR assay</td>
		</tr>
		<tr>
			<td>Camcorder</td>
			<td>Panasonic</td>
			<td>HDC-SD60</td>
			<td>Image documentation</td>
		</tr>
		<tr>
			<td>Axio Scope.A1</td>
			<td>ZEISS</td>
			<td>N/A</td>
			<td>Bright-field microscopy</td>
		</tr>
		<tr>
			<td>ScanScope&#9415; XT</td>
			<td>Aperio</td>
			<td>N/A</td>
			<td>Whole-field image scanner</td>
		</tr>
		<tr>
			<td>MetaMorph&#9415; Research Imaging</td>
			<td>Molecular Devices</td>
			<td>N/A</td>
			<td>Quantitative analysis of skin thickness and immune-reactive cells</td>
		</tr>
	</tbody>
</table>

development of an economical dna delivery system by "acufection" and its application to skin research

Dysregulation of immune response in skin is associated with numerous human skin disorders. Direct transfer of immune-related genes into skin tissue is a fascinating approach to investigate immune modulation of cutaneous inflammation in mouse models of human diseases. Here we present a cost-effective protocol that delivered naked DNA in mouse skin and leads to transgene expression. The method is coined &#34;acufection&#34;, denoting acupuncture-mediated DNA transfection. To perform acufection, mouse skin was first infused with DNA in phosphate-buffered saline (PBS) and then pricked lightly with a bundle of acupuncture needles to facilitate the absorption of DNA and transfection into cells. The plasmid DNA is presumably taken up by the keratinocyte and dendritic cells (DCs) in the skin and expressed into protein. Mechanical prick with the needles per se did not cause skin damage or induce keratinocyte activation. The expression of the transfected genes was detected in the skin at both transcriptional and translational levels following acufection for 2 days and maintained up to 7 days. The primary goal for the development of this acufection method was to investigate a previously undefined isoform of IL-15. Using this method, an alternatively spliced IL-15 isoform with partially deleted exon 7 (IL-15&#916;E7) was expressed in the skin and subsequently treated with a Toll-like receptor 7 (TLR7) agonist, imiquimod (IMQ), to induce inflammation. Acufection-delivered IL-15&#916;E7 in skin suppressed keratinocyte proliferation, epidermal thickness and neutrophil recruitment in IMQ-induced cutaneous inflammation. With increasing interest in identifying the regulatory mechanisms of cutaneous inflammation, the protocol described here provides a cost effective and versatile alternative to the gene gun system or microseeding for DNA delivery in vivo. It may potentially allow discovery of the function of a novel gene in the skin or for investigating new treatment for cutaneous diseases.

While some redness was evident within the first hour after pricking with acupuncture needles, the skin cleared on day 2 and no adverse skin reaction up to day 7 was observed after pricking (Figure 2A). Needle pricking induced very low level of epidermal orthokeratosis and minimal dermal infiltration by H&#38;E analysis compared with untreated skin (Figure 2B). The epidermal thickness (Figure 2C) and ...

Watch this Scientific Journal Video about Development of an Economical DNA Delivery System by "Acufection" and its Application to Skin Research at JoVE.com

Development of an Economical DNA Delivery System by &quot;Acufection&quot; and its Application to Skin Research

This protocol is a cost-effective alternative for expressing naked plasmid DNA in mouse skin. The overall goal of the protocol is to deliver immune-related genes into skin tissue to delineate the functional role of a specific gene in cutaneous inflammation.

Development of an Economical DNA Delivery System by "Acufection" and its Application to Skin Research

Dysregulation of immune response in skin is associated with numerous human skin disorders. Direct transfer of immune-related genes into skin tissue is a ...

The overall goal of this procedure is to deliver immune related genes into skin tissue to delineate the functional role of a specific gene in a cutaneus inflammation. This method can aid in discovering the function of a novel gene in the skin. For the development of new therapies for cutaneus disease such a psoriasis.The main advantage of this technique is that it provides a cost effective way to express plasmid DNA in mouse skin. To prepare the plasmid DNA inoculate three milliliters of antibiotic supplemented LB medium with the previously transformed and selected bacterial colony. Incubate the culture overnight on a shaker at 37 degrees celsius.After the overnight incubation dilute the bacterial culture in 250 milliliters of LB medium, supplemented with antibiotics to scale-up the culture. Incubate the culture overnight at 37 degrees Celsius with shaking. Use a high-quality endotoxin free plasmid preparation kit to prepare a large quantity of DNA.Dilute the obtained plasmid DNA in sterile PBS to a final concentration of one milligram per milliliter. After anesthetizing the mouse, apply veterinary ophthalmologic ointment to its eyes to prevent dryness. Then shave the skin on the back of the animal.And apply a depilatory cream to dissolve keratin proteins in the remaining hair shafts. Following depilation wipe off the cream with water soaked cotton. Using a sterile cotton swab, soaked in 70%ethanol disinfect the skin surface and mark the target skin area with the previously prepared template Apply 10 microliters of the DNA solution containing 10 micrograms of plasmid DNA to the desired skin area.To acufect the mouse, hold the acupuncture apparatus perpendicularly to the skin and repetitively puncture the designated surface. Either 100 times over 30 seconds or until the solution applied to the skin absorbs. To achieve successful plasmid DNA expression in the skin tissue, it is important avoid cutting deep into the skin and to make sure the DNA solution is well absorbed.After completing the procedure place the acufected mouse on a heating pad to maintain its body temperature until recovery from anesthesia. When the mouse regains sufficient consciousness return it to its cage and provide water and food. Closely monitor the mouse for any symptoms of discomfort including behavioral changes, abnormal appearance for the first 48 hours after the procedure.Mark the flank skin covering the area of two centimeters by two centimeters previously acufected with IL-15deltaE7. Then using a cotton applicator apply Imiquimod cream topically to the designated surface area. To monitor daily changes of the Imiquimod treated dorsal skin, have one researcher record while the second holds the mouse securely and exposes the treated area to the view of the high definition camcorder.Observe for such changes as silvery scale, plaque or erythema on the treated skin. After euthanizing the mouse as described, make a horizontal incision at the base of the tail using a pair of serological scissors and widen the cut bilaterally towards the base of each hind limb. Then proceed with vertical cuts that align with the flanks and reach each base of the four limbs.Carefully peel the skin from the underlying issue starting with the tail towards the head of the animal. Using scissors excise the dorsal skin and transfer the obtained sample to a sterile Petri dish. With a scalpel, excise a suitable sample of the target skin.Then immediately freeze it in liquid nitrogen. To pulverize the skin tissue, place the frozen sample at the center of a previously chilled two compartment tissue pulverizor equipped with handles and a pestle and use a lead hammer on the mortar. Immediately transfer the pulverized tissue into new tubes containing the reagents appropriate for any subsequent analysis.Begin the staining procedure by heating the slides of the formalin fixed paraffin embedded skin sections prepared as detailed in the text protocol, at 65 degrees celsius for 15 minutes. Immerse the slides twice in xylene for five minutes. Then rehydrate the slides through an ethanol gradient.Finally, wash the slides in tap water for three minutes before staining. For Immunohistochemical staining, first draw a circle around the tissue with waterproof pen and then incubate the section with blocking solution to exclude non-specific background staining. After blocking, was the side in PBS.Next pipette the diluted primary antibody onto the section and incubate it for 60 minutes at room temp temperature. Wash the slides thrice in TBST for five minutes. Then overlay one drop of the labeled polymer over the section and incubate the slide at room temperature for 40 minutes.Afterward, wash the slide thrice in TBST for five minutes changing the solution between washes. Then add 100 microliters of DAB solution onto the tissue sections and allow it to react at room temperature. Until a brown product is observed under the microscope.Then wash the slides in water to stop peroxidase activity. Counter stain the section in Methyl Green solution, which specifically binds to DNA for five seconds. Wash the slides three times in PBS for five minutes each.Overlay the stained section with eight microliters of permanent mounting medium and cover it with a cover slip. Finally, image the slides as described in the text protocol. Pictured here is a control mouse and a mouse that was acufected for one hour, two days, five days or seven days prior to when the photograph was taken.As shown here, the acufection procedure did not cause noticeable skin damage. Furthermore, acufection did not influence either skin thickness or the number of Ki67 positive cells. Further confirming that the procedure does not cause tissue disruption or epidermal cell proliferation.The expression of CXCL-1 and IL-6 measured using qRT-PCR. Confirms minimal keratinocyte activation observed under acufection. On the other hand, qRT-PCR and ELISA demonstrated the pronounced expression of IL-15 in the skin of mice acufected with the IL-15 gene.Ultimately, acufection mediated delivery of the IL-15deltaE7 gene to skin tissue prevents the development of flaky skin and neutrophil infiltration Imiquimod treated mice. Once mastered this procedure can be done in 12 minutes if it is performed properly. While attempting this procedure it is important to remember to prepare a new bundle of needles for each acufection ans a batch of high quality plasmid DNA.Following this procedure, other methods like virus infection can be performed in order to answer additional questions like the function of a novel gene in modulating antiviral immune response. After its development this will pave the way for researchers in the field of immunology to explore the immune response in the skin. After watching this video, you should have a good understanding of how to induce the expression of plasmid DNA in the mouse skin in a cost effective manner.

development-an-economical-dna-delivery-system-acufection-its

Research

JoVE Journal

Immunology and Infection

7.3K Görüntüleme.  National Taiwan University College of Medicine. The overall goal of this procedure is to deliver immune related genes into skin tissue to delineate the functional role of a specific gene in a cutaneus inflammation. This method can aid in discovering the function of a novel gene in the skin. For the development of new therapies for cutaneus disease such a psoriasis.The main advantage of this technique is that it provides a cost effective way to express plasmid DNA in mouse skin. To prepare the plasmid DNA inoculate three milliliters ...