We thank Professor Bin Chen, Dr. Yue Zhang, and Kendy Hoang for help with setting up the electroporation system. This work was supported by grants from the Santa Cruz Cancer Benefit Group and NIH to Z.A.W.

All procedures described here were performed in accordance with the guidelines and regulations from the Institutional Animal Care and Use Committee (IACUC) of University of California Santa Cruz.
1. Plasmid and Tools Preparation
<ol>
	<li>For each bladder to transfect, prepare at least 20 &#181;L of DNA plasmid (1 &#181;g/&#181;L).</li>
	<li>Add 1 &#181;L of Trypan Blue to the 20 &#181;L of plasmid solution in a 1.5 mL microcentrifuge tube. Pipette to mix well.</li>
	<li>Autoclave all surgic...

<ol>
	<li>Sharpless, N. E., Depinho, R. 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+mighty+mouse:+genetically+engineered+mouse+models+in+cancer+drug+development.">The mighty mouse: genetically engineered mouse models in cancer drug development.</a> Nat Rev Drug Discov. 5 (9), 741-754 (2006).</li><li>Heyer, J., Kwong, L. N., Lowe, S. W., Chin, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-germline+genetically+engineered+mouse+models+for+translational+cancer+research.">Non-germline genetically engineered mouse models for translational cancer research.</a> Nat Rev Cancer. 10 (7), 470-480 (2010).</li><li>Maddalo, 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=In+vivo+engineering+of+oncogenic+chromosomal+rearrangements+with+the+CRISPR/Cas9+system.">In vivo engineering of oncogenic chromosomal rearrangements with the CRISPR/Cas9 system.</a> Nature. 516 (7531), 423-427 (2014).</li><li>Xue, W., 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=CRISPR-mediated+direct+mutation+of+cancer+genes+in+the+mouse+liver.">CRISPR-mediated direct mutation of cancer genes in the mouse liver.</a> Nature. , (2014).</li><li>Sanchez-Rivera, F. 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=Rapid+modelling+of+cooperating+genetic+events+in+cancer+through+somatic+genome+editing.">Rapid modelling of cooperating genetic events in cancer through somatic genome editing.</a> Nature. 516 (7531), 428-431 (2014).</li><li>Romero, R., 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=Keap1+loss+promotes+Kras-driven+lung+cancer+and+results+in+dependence+on+glutaminolysis.">Keap1 loss promotes Kras-driven lung cancer and results in dependence on glutaminolysis.</a> Nat Med. 23 (11), 1362-1368 (2017).</li><li>Platt, R. 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=CRISPR-Cas9+knockin+mice+for+genome+editing+and+cancer+modeling.">CRISPR-Cas9 knockin mice for genome editing and cancer modeling.</a> Cell. 159 (2), 440-455 (2014).</li><li>Yin, 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=Genome+editing+with+Cas9+in+adult+mice+corrects+a+disease+mutation+and+phenotype.">Genome editing with Cas9 in adult mice corrects a disease mutation and phenotype.</a> Nat Biotechnol. 32 (6), 551-553 (2014).</li><li>Yang, Y., 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=A+dual+AAV+system+enables+the+Cas9-mediated+correction+of+a+metabolic+liver+disease+in+newborn+mice.">A dual AAV system enables the Cas9-mediated correction of a metabolic liver disease in newborn mice.</a> Nat Biotechnol. 34 (3), 334-338 (2016).</li><li>Negrete, H. O., Lavelle, J. P., Berg, J., Lewis, S. A., Zeidel, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Permeability+properties+of+the+intact+mammalian+bladder+epithelium.">Permeability properties of the intact mammalian bladder epithelium.</a> Am J Physiol. 271 (4 Pt 2), F886-F894 (1996).</li><li>Lilly, J. D., Parsons, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bladder+surface+glycosaminoglycans+is+a+human+epithelial+permeability+barrier.">Bladder surface glycosaminoglycans is a human epithelial permeability barrier.</a> Surg Gynecol Obstet. 171 (6), 493-496 (1990).</li><li>Ramesh, N., 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=Identification+of+pretreatment+agents+to+enhance+adenovirus+infection+of+bladder+epithelium.">Identification of pretreatment agents to enhance adenovirus infection of bladder epithelium.</a> Mol Ther. 10 (4), 697-705 (2004).</li><li>Yamashita, 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=Syn3+provides+high+levels+of+intravesical+adenoviral-mediated+gene+transfer+for+gene+therapy+of+genetically+altered+urothelium+and+superficial+bladder+cancer.">Syn3 provides high levels of intravesical adenoviral-mediated gene transfer for gene therapy of genetically altered urothelium and superficial bladder cancer.</a> Cancer Gene Ther. 9 (8), 687-691 (2002).</li><li>Engler, 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=Ethanol+improves+adenovirus-mediated+gene+transfer+and+expression+to+the+bladder+epithelium+of+rodents.">Ethanol improves adenovirus-mediated gene transfer and expression to the bladder epithelium of rodents.</a> Urology. 53 (5), 1049-1053 (1999).</li><li>Matsuda, T., Cepko, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electroporation+and+RNA+interference+in+the+rodent+retina+in+vivo+and+in+vitro.">Electroporation and RNA interference in the rodent retina in vivo and in vitro.</a> P Natl Acad Sci USA. 101 (1), 16-22 (2004).</li><li>Yarmush, M. L., Golberg, A., Sersa, G., Kotnik, T., Miklavcic, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electroporation-based+technologies+for+medicine:+principles,+applications,+and+challenges.">Electroporation-based technologies for medicine: principles, applications, and challenges.</a> Annu Rev Biomed Eng. 16, 295-320 (2014).</li><li>Saito, T., Nakatsuji, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+gene+transfer+into+the+embryonic+mouse+brain+using+in+vivo+electroporation.">Efficient gene transfer into the embryonic mouse brain using in vivo electroporation.</a> Dev Biol. 240 (1), 237-246 (2001).</li><li>Boutin, C., Diestel, S., Desoeuvre, A., Tiveron, M. C., Cremer, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+in+vivo+electroporation+of+the+postnatal+rodent+forebrain.">Efficient in vivo electroporation of the postnatal rodent forebrain.</a> PLoS One. 3 (4), e1883 (2008).</li><li>Saito, T. <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+electroporation+in+the+embryonic+mouse+central+nervous+system.">In vivo electroporation in the embryonic mouse central nervous system.</a> Nat Protoc. 1 (3), 1552-1558 (2006).</li><li>Molotkov, D. A., Yukin, A. Y., Afzalov, R. A., Khiroug, L. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+delivery+to+postnatal+rat+brain+by+non-ventricular+plasmid+injection+and+electroporation.">Gene delivery to postnatal rat brain by non-ventricular plasmid injection and electroporation.</a> J Vis Exp. (43), (2010).</li><li>Walantus, W., Castaneda, D., Elias, L., Kriegstein, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+utero+intraventricular+injection+and+electroporation+of+E15+mouse+embryos.">In utero intraventricular injection and electroporation of E15 mouse embryos.</a> J Vis Exp. (6), e239 (2007).</li><li>Follenzi, A., Santambrogio, L., Annoni, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immune+responses+to+lentiviral+vectors.">Immune responses to lentiviral vectors.</a> Curr Gene Ther. 7 (5), 306-315 (2007).</li></ol>

The authors declare no competing interest.

Electroporation enhances the cell membrane permeability and is a powerful technology for gene electrotransfer16. Gene delivery into living rodents by electroporation has been frequently used in neurobiology fields17,18,19,20,21. Its potential applications in many other organs have not been extensively explored. To our knowledge, our met...

Genetically engineered mouse models (GEMMs) have been playing an essential role in expanding our knowledge about animal development, gene functions in vivo, and mechanisms of disease progression1,2. Germline GEMMs are traditionally developed in two ways. The first is the creation of transgenic mice by pronuclear injection of DNA plasmid followed by the transplantation of zygotes into pseudopregnant females. The other is the generation of knock-out/knock-in mice by homologous recombination in embryonic stem cells and the development of chimeras. Conditional knockout of genes in specific tissue or cell type of interest involves the breeding of genetically engineered alleles with Cre and flox sites for multiple generations. The whole process can be expensive and time-consuming, especially if the goal is to target multiple genes tissue-specifically. Recently, gene-editing technologies such as clustered regularly interspaced short palindromic repeats (CRISPR) have been applied to several organs of the mice to induce tissue-specific genetic alterations for autochthonous cancer modeling3,4,5,6,7 or correct disease mutations in situ8,9. In these studies, the delivery of the gRNA vectors was usually achieved through adenoviral or lentiviral infection of the organ or hydrodynamic tail-vein injection. The relative ease of delivery of the CRISPR components to the lung and liver has greatly improved the convenience and efficiency of cancer modeling in these organs compared to the traditional Cre-Lox based mouse models.
The bladder urothelium is where most bladder tumors originate. The delivery of DNA vectors to the bladder urothelium for cancer modeling or gene therapy is hampered by a glycosaminoglycan layer on the apical urothelial surface, which acts as a barrier for adherence of infectious viruses10,11. Several pretreatment agents such as Syn3 and dodecyl-&#946;-d-maltoside have been used to disrupt this barrier and enhance adenovirus infection efficiency12,13,14. Whether adeno-associated viruses (AAVs) can effectively infect the bladder has not been reported. Overall, a non-viral based delivery method would be desirable. Here, we describe a novel method developed in the lab for efficient DNA plasmid delivery to the mouse urothelium through urethra catheterization and electroporation. Because our approach does not involve chemical pretreatment of the glycosaminoglycan layer or virus production, it significantly simplifies the delivery of DNA plasmids into the mouse bladder urothelium, and should facilitate various in vivo studies of bladder diseases.

<table>
	<tbody>
		<tr>
			<td>BD 1mL TB Syringe</td>
			<td>Fisher</td>
			<td>148232E</td>
			<td></td>
		</tr>
		<tr>
			<td>Buprenorphine</td>
			<td>Sigma</td>
			<td>B9275-50MG</td>
			<td></td>
		</tr>
		<tr>
			<td>Dumont Tweezers</td>
			<td>Roboz Surgical Instr</td>
			<td>RS-5005</td>
			<td>Treat with 70% ethanol before surgical use</td>
		</tr>
		<tr>
			<td>ECM830 SQ Wave Electroporator</td>
			<td>Harvard Apparatus</td>
			<td>450052</td>
			<td></td>
		</tr>
		<tr>
			<td>Exel International Disposable Safelet I.V. Catheters</td>
			<td>Fisher Scientific</td>
			<td>14-841-21</td>
			<td>24G, 2.11 cm length, 0.045 cm outer diameter</td>
		</tr>
		<tr>
			<td>Extra Fine Micro Dissecting Scissors</td>
			<td>Roboz Surgical Instr</td>
			<td>RS-5135</td>
			<td>Treat with 70% ethanol before surgical use</td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Vet one</td>
			<td>501017</td>
			<td></td>
		</tr>
		<tr>
			<td>K&#38;H Heated Resting Mat for Small Animals, 9 By 12 Inches</td>
			<td>Amazon</td>
			<td>n/a</td>
			<td>Cover the heat mat with paper towels</td>
		</tr>
		<tr>
			<td>Ophthalmic ointment</td>
			<td>Fisher</td>
			<td>NC0849514</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS, pH7.4</td>
			<td>Life Technologies</td>
			<td>10010049</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipet tips 200 &#181;L</td>
			<td>USA Scientific</td>
			<td>1111-0206</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipet Tips, Universal Fit; 0.1 to 10 &#181;L</td>
			<td>Fisher</td>
			<td>02707438(CS)</td>
			<td></td>
		</tr>
		<tr>
			<td>PIPETMAN NEO P2</td>
			<td>Gilson</td>
			<td>F144561</td>
			<td></td>
		</tr>
		<tr>
			<td>PIPETMAN NEO P200N</td>
			<td>Gilson</td>
			<td>F144565</td>
			<td></td>
		</tr>
		<tr>
			<td>plasmid CAG-GFP</td>
			<td>Addgene</td>
			<td>16664</td>
			<td></td>
		</tr>
		<tr>
			<td>Platinum tweezertrode 5 mm</td>
			<td>Harvard Apparatus</td>
			<td>450489</td>
			<td>5 mm diameter</td>
		</tr>
		<tr>
			<td>Scissors</td>
			<td>Roboz Surgical Instr</td>
			<td>RS-5880</td>
			<td>Treat with 70% ethanol before surgical use</td>
		</tr>
		<tr>
			<td>String cord</td>
			<td>Amazon</td>
			<td>n/a</td>
			<td>Mandala Crafts 150D 210D 0.8mm 1mm leather sewing stitching flat waxed thread string cord</td>
		</tr>
		<tr>
			<td>Tape, Scotch</td>
			<td>Fisher</td>
			<td>19047257</td>
			<td></td>
		</tr>
		<tr>
			<td>Therio-gel Veterinary Lubricant</td>
			<td>PBS animal health</td>
			<td>353-736</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue Stain</td>
			<td>Life Technologies</td>
			<td>15250061</td>
			<td></td>
		</tr>
		<tr>
			<td>V-1 Table top system anesthesia</td>
			<td>VetEquip</td>
			<td>901806</td>
			<td></td>
		</tr>
		<tr>
			<td>Vicryl violet suture 18&#34; FS-2 cutting 5-0</td>
			<td>Fisher</td>
			<td>NC0578475</td>
			<td></td>
		</tr>
		<tr>
			<td>Walgreens Povidone Iodine 10%</td>
			<td>Walgreens</td>
			<td>953982</td>
			<td></td>
		</tr>
		<tr>
			<td>Wound clip</td>
			<td>Fisher</td>
			<td>018045</td>
			<td></td>
		</tr>
		<tr>
			<td>Wound clip applier</td>
			<td>Fisher</td>
			<td>01804</td>
			<td></td>
		</tr>
	</tbody>
</table>

novel method of plasmid dna delivery to mouse bladder urothelium by electroporation

Genetically engineered mouse models (GEMMs) are extremely valuable in revealing novel biological insights into the initiation and progression mechanisms of human diseases such as cancer. Transgenic and conditional knockout mice have been frequently used for gene overexpression or ablation in specific tissues or cell types in vivo. However, generating germline mouse models can be time-consuming and costly. Recent advancements in gene editing technologies and the feasibility of delivering DNA plasmids by viral infection have enabled rapid generation of non-germline autochthonous mouse cancer models for several organs. The bladder is an organ that has been difficult for viral vectors to access, due to the presence of a glycosaminoglycan layer covering the urothelium. Here, we describe a novel method developed in lab for efficient delivery of DNA plasmids into the mouse bladder urothelium in vivo. Through intravesical instillation of pCAG-GFP DNA plasmid and electroporation of surgically exposed bladder, we show that the DNA plasmid can be delivered specifically into the bladder urothelial cells for transient expression. Our method provides a fast and convenient way for overexpression and knockdown of genes in the mouse bladder, and can be applied to building GEMMs of bladder cancer and other urological diseases.

To demonstrate the success of gene delivery into the bladder urothelium, we used the pCAG-GFP15 plasmid for electroporation. 20 &#181;L of plasmid and Trypan Blue solution was injected through the urethra and 5 electric pulses were administered. After 48 h, we dissected the mouse bladder and observed patches of GFP fluorescence under a dissection fluorescence microscope, whereas a negative control bladder that did not undergo electroporation showed no GFP signal (<...

Watch this Scientific Journal Video about Novel Method of Plasmid DNA Delivery to Mouse Bladder Urothelium by Electroporation at JoVE.com

Novel Method of Plasmid DNA Delivery to Mouse Bladder Urothelium by Electroporation

We describe a novel method for the delivery of DNA plasmid into the urothelial cells of mouse bladder in vivo through urethra catheterization and electroporation. It offers a fast and convenient way for generating autochthonous mouse models of bladder diseases.

Genetically engineered mouse models (GEMMs) are extremely valuable in revealing novel biological insights into the initiation and progression mechanisms ...

The overall goal of this method is to deliver DNA plasmids into the bladder urothelium of live mice in vivo for gene overexpression or genome editing. This method can help answer key questions in the bladder cancer field, such as how do different genetic mutations promote bladder cancer progression? The main advantage of this technique is that it provides a fast and convenient way for delivering genes into bladder without the safety concerns and technical barriers associated with viral vectors.I first had the idea for this method of trying to use any engineered associated viruses for DNA delivery, which didn't work well the bladder. The implication of this technique can also extend towards gene therapy because electroporation can achieve efficient delivery of DNA plasmids into the urothelial cells. Demonstrating the procedure will be Ofir Stefanson and Yueli Liu from my laboratory.To begin this procedure, autoclave all surgical instruments and sterilize the workspace with 70%ethanol. Spray surgical instruments and the gloves with 70%ethanol frequently when performing the subsequent procedures to maintain sterile conditions. To begin, anesthetize the mouse and shave the surgical area.To deplete the urine, apply lubricant to the catheter and ensure that its outer surface is fully covered. Next, insert the catheter into the urethra opening of the mouse and slowly push it until it reaches the bladder. Gently press the abdomen to help urine depletion.Subsequently, discard the urine with a pipette into a waste beaker, then pipette 80 microliters of PBS into the outer end of the catheter with the other end still in the bladder. Next, carefully attach a one millimeter syringe to the catheter. Gently push the syringe to inject PBS into the bladder.Leave some PBS in the catheter to avoid creating air bubbles in the bladder. Afterward, remove the syringe and wait for PBS to drain out of the bladder. Gently press the abdomen to evacuate PBS, then discard the PBS in the catheter with a pipette into the waste beaker.Repeat PBS washing for two more times. For each bladder to transfect, prepare at least 20 microliters of DNA plasmid at one microgram per microliter. Next, add one microliter of trypan blue to the 20 microliters of plasmid solution and a 1.5 milliliter microcentrifuge tube and pipette to mix well.To deliver the plasmid, apply 70%ethanol to the abdomen. Make a vertical incision of one centimeter to open the abdominal skin above the bladder. Next, cut the muscle layer to expose the bladder.Pipette at least 20 microliters of plasmid plus trypan blue solution into the outer end of the catheter and detach it to the syringe. Then, inject the plasmid solution into the bladder. If the bladder turns blue, the injection is successful.Leave some liquid in the catheter to avoid creating air bubbles in the bladder. Afterward, grab the external urethral oraifice and remove the catheter and syringe. Use a string to tighten the external urethral orifice.Make two loops with the string, and then tie with two knots. This is a crucial step that requires two people to cooperate. Make sure the knots are tight so the plasmids will not leak out.Now, turn on the electroporation generator. Pinch the bladder with two electrodes and push the foot pedal to perform electroporation. To keep the bladder propped one can pinch the back of the abdominal incision with tweezers.Avoid any contact between tweezers and the electrodes as this may generate a spark. When it is done, suture the abdominal and skin opening with sterile, surgical suture. Remove the string and apply clips.Apply iodine onto the wound, and then remove the animal from the isoflurane system. Administer buprenorphine analgesic subcutaneously to alleviate post surgical pain. Keep the animal on the heating pad and return it to the home cage after full recovery.Check the animal at least once daily for normal mobility, drinking and feeding behaviors, and no signs of infection until the incision is healed. Then, a week later, remove the clips. Administer subsequent injections of buprenorphine analgesic if the animal displays pain symptoms such as reduced grooming, increased aggressiveness, and vocalization.To demonstrate successful gene delivery into the bladder urothelium, 20 microliters of pCAG-GFP plasmid and trypan blue solution was injected through the urethra and five electric pulses were administered. Shown here is the successful electroporation that turned the bladder green after 48 hours, whereas a negative control bladder that did not undergo electroporation showed no GFP signal. Immunofluorescent staining of sectioned bladder tissues was performed with CK5, CK18, and GFP antibodies.GFP signal was observed to be present in umbrella, intermediate, and basal cells, but not at the muscle layer indicating good specificity of plasmid delivery into the urothelium. Once mastered, this technique can be performed in 15 minutes if performed properly. After its development, this technique paves the way for researchers in the field of bladder cancer to build new autochthonous mouse models to study disease progression mechanisms.

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8.4K vistas.  University of California, Santa Cruz. The overall goal of this method is to deliver DNA plasmids into the bladder urothelium of live mice in vivo for gene overexpression or genome editing. This method can help answer key questions in the bladder cancer field, such as how do different genetic mutations promote bladder cancer progression? The main advantage of this technique is that it provides a fast and convenient way for delivering genes into bladder without the safety concerns and technical barriers associated with viral vector...