We thank Dr Matthieu Rousseau for critical reading of the manuscript and the Laboratory of Dendritic Immunobiology for their helpful insights during the development of this protocol and project. This work was supported in part by funding from the European Union Seventh Framework Programme Marie Curie Action (PCIG11-GA- 2012-3221170, and the Immuno-Oncology LabEx (MAI).

Mouse experiments were conducted in accordance with approval of protocol number 2012-0024 by the Comit&#233; d&#39;&#233;thique en exp&#233;rimentation animale Paris Centre et Sud (the ethics committee for animal experimentation), in application of the European Directive 2010/63 EU.
1. Preparation of Catheters
<ol>
	<li>Prepare one pediatric intravenous-access cannula for each group of mice to be infected. Using the inbuilt spring mechanism, divest each cannula of its needle, as instructed b...

<ol>
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E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnosis+and+treatment+of+uncomplicated+urinary+tract+infection.">Diagnosis and treatment of uncomplicated urinary tract infection.</a> Infect Dis Clin North Am. 11 (3), 551-581 (1997).</li><li>Harper, M., Fowlis, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Management+of+urinary+tract+infections+in+men.">Management of urinary tract infections in men.</a> Trends in Urology, Gynaecology &amp; Sexual Health. 12 (1), 30-35 (2007).</li><li>Foxman, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+epidemiology+of+urinary+tract+infection.">The epidemiology of urinary tract infection.</a> Nat Rev Urol. 7 (12), 653-660 (2010).</li><li>Lipsky, B. 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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=Decreased+tumorigenesis+and+mortality+from+bladder+cancer+in+mice+lacking+urothelial+androgen+receptor.">Decreased tumorigenesis and mortality from bladder cancer in mice lacking urothelial androgen receptor.</a> Am J Pathol. 182 (5), 1811-1820 (2013).</li><li>El Behi, 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=An+essential+role+for+decorin+in+bladder+cancer+invasiveness.">An essential role for decorin in bladder cancer invasiveness.</a> EMBO Mol Med. 5 (12), 1835-1851 (2013).</li><li>Foxman, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidemiology+of+urinary+tract+infections:+incidence,+morbidity,+and+economic+costs.">Epidemiology of urinary tract infections: incidence, morbidity, and economic costs.</a> Am J Med. 113, 05S-13S (2002).</li><li>Ingersoll, M. A., Kline, K. A., Nielsen, H. V., Hultgren, 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=G-CSF+induction+early+in+uropathogenic+Escherichia+coli+infection+of+the+urinary+tract+modulates+host+immunity.">G-CSF induction early in uropathogenic Escherichia coli infection of the urinary tract modulates host immunity.</a> Cell Microbiol. 10 (12), 2568-2578 (2008).</li><li>Mora-Bau, G., 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=Macrophages+Subvert+Adaptive+Immunity+to+Urinary+Tract+Infection.">Macrophages Subvert Adaptive Immunity to Urinary Tract Infection.</a> PLoS Pathog. 11 (7), e1005044 (2015).</li><li>Oliveira, P. 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=Technical+Report:+Technique+of+Bladder+Catheterization+in+Female+Mice+and+Rats+for+Intravesical+Instillation+in+Models+of+Bladder+Cancer.">Technical Report: Technique of Bladder Catheterization in Female Mice and Rats for Intravesical Instillation in Models of Bladder Cancer.</a> (Conference Title)39th Scand-LAS and ICLAS Joint Meeting. 36, 5-9 (2009).</li><li>Seager, C. 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=Intravesical+delivery+of+rapamycin+suppresses+tumorigenesis+in+a+mouse+model+of+progressive+bladder+cancer.">Intravesical delivery of rapamycin suppresses tumorigenesis in a mouse model of progressive bladder cancer.</a> Cancer Prev Res (Phila). 2 (12), 1008-1014 (2009).</li><li>Hagberg, 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=Ascending,+unobstructed+urinary+tract+infection+in+mice+caused+by+pyelonephritogenic+Escherichia+coli+of+human+origin).">Ascending, unobstructed urinary tract infection in mice caused by pyelonephritogenic Escherichia coli of human origin).</a> Infect Immun. 40 (1), 273-283 (1983).</li><li>Olson, P. D., Hruska, K. A., Hunstad, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Androgens+Enhance+Male+Urinary+Tract+Infection+Severity+in+a+New+Model.">Androgens Enhance Male Urinary Tract Infection Severity in a New Model.</a> J Am Soc Nephrol. , (2015).</li><li>Knipper, J. 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=Interleukin-4+Receptor+alpha+Signaling+in+Myeloid+Cells+Controls+Collagen+Fibril+Assembly+in+Skin+Repair.">Interleukin-4 Receptor alpha Signaling in Myeloid Cells Controls Collagen Fibril Assembly in Skin Repair.</a> Immunity. 43 (4), 803-816 (2015).</li><li>Hung, C. S., Dodson, K. W., Hultgren, S. 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Transurethral instillation of male mice offers many new research opportunities into the influence of sex on bladder mucosal disease, but also presents several challenges. Foremost, one limitation is that the instillation may initially prove to be technically difficult, resulting in excessive inflammation during catheter insertion. Improvement in technique can be achieved by the instillation of dead mice with a colored solution, such as Evans blue dye. To confirm that the instillation is successful, bladders should be vis...

Urinary tract infections (UTI) are one of the most common infections in developed countries1. Infection rates are similar between females and males among neonates and the elderly2. Premenopausal adult women, however, have a greatly increased incidence of community-acquired UTI compared to men2,3. Given that this disease primarily impacts women, fundamental and clinical research has overwhelmingly focused on UTI in females. However, UTI in men is a significant and understudied health care challenge4. Indeed, because UTI in men are associated with higher morbidity, these infections are routinely defined as complicated4,5.
As our understanding of the central role of sex biases in physiology and pathology evolves, new methods are required to explore this previously neglected aspect of disease. Sex differences play an essential role in immunity and infection; females have higher incidence of autoimmune disease, while males are more susceptible to certain infections, such as tuberculosis, malaria, and HIV6,7. Bladder cancer, another urologic pathology, is significantly more prevalent in men than in women, and several studies have shown a role for androgens in the development of malignancy8,9,10,11,12. Notably, however, investigation of intravesical therapies for bladder cancer is performed exclusively in female animals, due to the inability to repeatedly catheterize male mice13.
The study of UTI pathogenesis relies heavily on rodent models of infection (e.g., mice and rats). Murine models of UTI may employ uropathogens originally isolated from human infections, such as uropathogenic E. coli (UPEC), Klebsiella, Enterococcus, Staphylococcus, or Proteus14. Typically, bacteria are introduced into the bladder via catheterization of the urethra. Following infection, bladders and kidneys can be removed to assess specific parameters of infection, such as bacterial colonization, tissue damage, or host immune response15,16. Universally, however, only female animals are used for UTI research. Indeed, many studies have noted that, due to anatomical reasons, catheterization of male mice is not possible13,17,18,19. More recently, a surgical approach to male instillation has been described, in which the abdomen is opened, the bladder is externally displaced by applying gentle pressure to the opening in the abdomen, and bacteria are injected into the bladder20. This approach enables male infection, at the cost of surgical intervention. Thus, a major caveat of this approach includes the influence of inflammation, on the outcome of infection such as the potential to induce an anti-inflammatory wound-healing response to the incision21. As our interests include understanding sex bias in response to disease, we developed a method of bacterial intravesical instillation in male mice that more closely matches the long-established non-surgical transurethral approach used in female rodents22.
Our model builds upon an established methodology and provides the ability to directly compare the host immune response to UTI in female and male animals. This method will permit dissection of sex-based differences in infection, and potentially offer molecular and cellular clues to the pronounced differences in susceptibility and response to infection between the sexes. Additionally, this model has value beyond UTI studies, allowing the establishment of models to investigate other bladder-associated diseases, such as bladder cancer, prostatitis, under- or over-active bladder syndrome, and interstitial cystitis.

<table border="0" cellpadding="0" cellspacing="0" width="808">
	<tbody>
		<tr height="45">
			<td height="45" style="height:45px;width:283px;">BD Insyte Autoguard Shielded IV Catheters 24G, 0.7 mm external diameter, 14 mM long</td>
			<td style="width:131px;">BD Medical</td>
			<td style="width:135px;">381811 or 381411*</td>
			<td style="width:260px;">* catalog number is country-dependent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">inoculating loop</td>
			<td style="width:131px;">Greiner Bio-One</td>
			<td style="width:135px;">731171</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">LB Miller broth</td>
			<td style="width:131px;">Difco</td>
			<td style="width:135px;">244620</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">LB Miller agar</td>
			<td style="width:131px;">Difco</td>
			<td style="width:135px;">244520</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">Cuvettes</td>
			<td style="width:131px;">Bio-rad</td>
			<td style="width:135px;">223-9955</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">syringes</td>
			<td style="width:131px;">B Braun</td>
			<td style="width:135px;">9166017V</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">Thumb (Adson) forceps</td>
			<td style="width:131px;">Fine Science Tools</td>
			<td style="width:135px;">11006-12</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">5 mL tubes, polypropylene</td>
			<td style="width:131px;">Falcon</td>
			<td style="width:135px;">352063</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">Tissue Ruptor disposable probes</td>
			<td style="width:131px;">Qiagen</td>
			<td style="width:135px;">990890</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">15 mL flip cap tubes</td>
			<td style="width:131px;">Thermo Scientific</td>
			<td style="width:135px;">362694</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">DNAse</td>
			<td style="width:131px;">Invitrogen</td>
			<td style="width:135px;">18047019</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:283px;">Liberase TM</td>
			<td style="width:131px;">Sigma-Aldrich</td>
			<td style="width:135px;">5401119001</td>
			<td style="width:260px;">should be aliquotted and stored at -20 &#176;C to avoid repeated freeze-thaw</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:283px;">100 &#181;M MACS SmartStrainers&#160;</td>
			<td style="width:131px;">Miltenyi</td>
			<td style="width:135px;">130-098-463</td>
			<td style="width:260px;">compatible with 15 mL tubes, preferred</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:283px;">100 &#181;m cell strainers&#160;</td>
			<td style="width:131px;">Falcon</td>
			<td style="width:135px;">352360</td>
			<td style="width:260px;">compatible with 50 mL tubes, if MACS Smart Strainers are not available</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">96 well plate</td>
			<td style="width:131px;">Falcon</td>
			<td style="width:135px;">353077</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">Fc block</td>
			<td style="width:131px;">BD Pharmingen</td>
			<td style="width:135px;">553142</td>
			<td style="width:260px;">anti-CD16/CD32</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:283px;">anti-mouse CD45 antibody</td>
			<td style="width:131px;">BD Biosciences</td>
			<td style="width:135px;">561487</td>
			<td style="width:260px;">many different fluorescent conjugation options are available</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">5 mL tubes polystyrene with filter cap</td>
			<td style="width:131px;">Falcon</td>
			<td style="width:135px;">352235</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">insulin syringe</td>
			<td style="width:131px;">Terumo</td>
			<td style="width:135px;">BS05M2913</td>
			<td style="width:260px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">hand held homogenizer</td>
			<td style="width:131px;">Qiagen</td>
			<td style="width:135px;">9001272</td>
			<td style="width:260px;">TissueRuptor</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">flow cytometer</td>
			<td style="width:131px;">BD Biosciences</td>
			<td style="width:135px;">N/A</td>
			<td style="width:260px;">Fortessa SORP&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:283px;">Flow cytometry software</td>
			<td style="width:131px;">BD Biosciences</td>
			<td style="width:135px;">N/A</td>
			<td style="width:260px;">Diva</td>
		</tr>
	</tbody>
</table>

urinary tract infection in a small animal model: transurethral catheterization of male and female mice

Urinary tract infections (UTI) are extremely common worldwide, incurring significant morbidity and healthcare-associated expenses. Small animal models, which accurately reflect disease establishment and progression, permit dissection of host-pathogen interactions and generation of immunity to infection. In mice, intravesical instillation of uropathogenic E. coli, the causative agent in more than 85% of community acquired UTI, recapitulates many of the stages of infection observed in humans. Until recently, however, UTI could only be modeled in female animals. This limitation has hindered the study of sex-related differences in UTI, as well as other bladder pathologies, such as cancer. Here, we describe a method to instill male mice that allows direct comparison between female and male animals and provide a detailed protocol to assess bladder tissue by flow cytometry as a means to better understand host responses to infection. Together, these approaches will aid in the identification of host factors that contribute to sex biases observed in UTI and other bladder-associated diseases.

In the development of this protocol, cohorts of female and male C57Bl/6 mice aged 6 to 8 weeks were instilled, and bacterial burden evaluated in bladders at time points ranging from 1 hr to 30 days. The results from these studies are detailed elsewhere (Zychlinsky Scharff et al., pending). Here, we present representative data from 24 hr infections. Notably, bacterial burden was equivalent between male and female mice at 24 hr post-infection (Figure 1). Little var...

Watch this Scientific Journal Video about Urinary Tract Infection in a Small Animal Model: Transurethral Catheterization of Male and Female Mice at JoVE.com

Urinary Tract Infection in a Small Animal Model: Transurethral Catheterization of Male and Female Mice

The established model of transurethral catheterization of mice allows the study of bladder pathologies, including urinary tract infection, but can only be performed in females. A new model of male transurethral instillation, presented here, will enable research in an area marked by strong clinical and epidemiological differences between the sexes.

Urinary tract infections (UTI) are extremely common worldwide, incurring significant morbidity and healthcare-associated expenses. Small animal models, ...

The overall goal of this experimental approach is to investigate the immune response to urinary tract infection, and to prevent direct comparison between male and female animals. This method can help answer key questions of mucosal immunology related to how males and females respond to urinary tract infection. The main advantage is that infection is established via the natural root.We first had the idea for this method after noting how often it is stated, that the installation of the bladder of the male mice is impossible. Though this method will provide insight into urinary tract infection, it can also be applied to other disease studies, such as bladder cancer. To begin, prepare one pediatric intravenous access canula for each group of mice to be infected.Using the inbuilt spring mechanism, divest each canula of its needle as instructed by the manufacturer. Discard the needles, preserving only the plastic intravenous canula. Sterilize the catheters in a laminar flow hood for one UV cycle of approximately 25 to 30 minutes.After going in overnight culture of uropathogenic e coli, or UPEC, according to the text protocol, spin the bacterial suspension in a table-top microcentrifuge at 17, 000 times g for one minute, and resuspend the resulting bacterial pellet at two times 10 to the eighth CFU per milliliter in PBS. Serially dilute an aliquot of suspension, and plate on LB agar with antibiotics if appropriate, to determine the exact inoculum for each infection. Draw the bacterial inoculum into a one milliliter syringe, and attach the catheter to the end of the syringe.Tap the syringe to remove any air, and depress the plunger to fill the dead air space in the catheter before beginning the instillation. After anesthetizing a female mouse according to an approved protocol, place the animal supine, and apply medium pressure to the lower abdomen to empty the bladder of urine. Full bladders feel like a pea under the skin, between the iliac crests.When the bladder is empty, using the non-dominant hand, place the thumb on the tail and a finger of the same hand on the abdomen of the mouse, and apply gentle pressure in opposing directions to hold the mouse firmly in place. Next, place the tip of the catheter perpendicular to the mouse at the urethral orifice, then, with gentle pressure, slide the catheter into the urethra until the hub meets the urethral orifice, while simultaneously lowering the syringe so that it is parallel to the working surface. Once the catheter is in place, use a finger from the non-dominant hand that's resting on the mouse abdomen to very gently pull the abdominal skin towards the head of the mouse.Note that the urethral orifice will not move. However, if the catheters is in the vagina, the tissue will move up and away from the catheter. With the hub of the catheter against the urethral orifice, slowly dispense 15 microliters of the bacterial inoculum.A slow installation rate minimizes vesicoureteral reflux into the kidney. Slowly remove the catheter to prevent leakage. Then place the animal in its cage in a supine position.To inoculate male mice, place two thumb forceps cranially and caudally to the mouses external genitalia. Retract the prepuce to fully expose the gland's penis. Then, once the penis is externally positioned, release the thumb forceps.Reposition the forceps to stabilize the protruding penis perpendicular to the animal, holding the organ gently but tautly. Then through the small opening in the tip of the urethral meatus, carefully introduce the catheter and gently guide it into the penis using forceps to gently maintain tension. Once the hub of the catheters meets the tip of the penis, very slowly dispense 50 microliters of the inoculum, while maintaining the position of the penis.Note the quality of the instillation according to a predetermined instillation quality score, such as the one shown here. Retract the catheter slowly over five seconds to prevent leakage of the inoculum. Place the mouse in its cage in a supine position.The animal should begin to recover 30 to 45 minutes following administration of the anesthetic. After sacrificing mice according to an approved protocol, use 70%Epinal to moisten the abdomen thoroughly to minimize contamination by the fur. Using scissors, make a two centimeter incision across the lower third of the mouses abdomen, and aseptically remove the bladder and any other desired organs.Transfer the organs into five milliliter polypropylene snap-cap tubes, containing one milliliter of sterile PBS and keep all samples on ice. With a hand-held homogenizer, homogenize the organs until almost no solid tissue remains. Discard any shiny, beige-white fat tissue that does not homogenize well.Then, use Epinal, followed by PBS to wash the homogenizer between each experimental or organ group. After preparing serial dilutions of homogenized organ suspension, plate dilutions on LB agar plates, with antibiotics when appropriate, and incubate at 37 degrees Celsius overnight. To carry out flow cytometry on bladder tissue, after isolating the bladder as demonstrated earlier in this video, use scissors to mince the tissue well.Add one minced bladder per tube containing digestion buffer. Then shake the tube to wash the minced tissue in the digestion buffer, and keep it on ice until all the bladders are dissected and minced. Incubate the minced bladders at 37 degrees Celsius, for 60 to 75 minutes with vigorous shaking by hand for five seconds, every 15 minutes.When the tissue has a glassy transparent appearance resembling wet tissue paper, digestion is complete. Inactivate the digestion enzymes by adding two to three milliliters of ice-cold flow cytometry buffer, and gently mix. Then place the tubes on ice.To ensure a single-cell suspension, and to remove any connective tissue, pass the contents of the tube through a 100 micrometer filter placed in a 15 milliliter conical tube. Then, with the end of a syringe plunger, gently press any remaining tissue through the filter. Wash the filter with an additional two milliliters of flow cytometry buffer, and keep the samples on ice.The wash the samples by centrifugation at 200 times g and four degrees Celsius, for seven minutes. Resuspend the pellets in 100 microliters of flow cytometry buffer containing Fc block, diluted to five micrograms per milliliter, and transfer to a 96 Well round bottom plate. After 10 to 15 minutes add 100 microliters of the desired antibody cocktail to each sample.Then incubate the samples on ice protected from light for 30 to 45 minutes. Wash the samples by centrifugation at 200 times g and four degrees Celsius for seven minutes. Finally, resuspend the cell pellets in 200 microliters of flow cytometry buffer, and pass the samples through a 40 micrometers cell strainer on a five milliliter polystyrene tube, just prior to acquisition on a flow cytometer.This figure shows representative data from mice infected for 24 hours. Bacterial burden was equivalent between male and female mice at 24 hours post infection. To determine whether loss of inoculum at the time of infection impacted the establishment of infection each instillation was scored on a scale of one to five, with one being the most optimal.Bacterial colonization was determined 24 hours post infection. No statistically significant differences were found among the CFU's obtained from animals with different instillation scores as assessed by a nonparametric Kruskal-Wallis test, comparing the mean rank of each column with the mean rank of every other column, and correcting for multiple comparisons using a Dunn's test. It can be concluded that suboptimal instillations, resulting in substantial leakage of bacterial inoculum during infection, do not significantly impact bacterial colonization at 24 hours.Importantly, the frequency of suboptimal instillation will decrease with practice. Finally, while the number of CD45 positive immune cells, present in naive animals was not different between female and male mice, there was a statistically-significant increase in infiltration into the bladders of infected female mice. While attempting catheterization, it is important to use slow, gentle movements.With its development, this technique has helped us to explore sex-based differences in immunity in the bladder of male and female animals.

urinary-tract-infection-small-animal-model-transurethral

Research

JoVE Journal

Immunology and Infection

15.8K 조회수.  Institut Pasteur, INSERM U818. The overall goal of this experimental approach is to investigate the immune response to urinary tract infection, and to prevent direct comparison between male and female animals. This method can help answer key questions of mucosal immunology related to how males and females respond to urinary tract infection. The main advantage is that infection is established via the natural root.We first had the idea for this method after noting how often it is stated, that the installation of the b...