Name: a delayed inoculation model of chronic pseudomonas aeruginosa wound infection
Uploaded: 2020-02-20T12:30:00
Description: Watch this Scientific Journal Video about A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection at JoVE.com

The pUT-Tn5-EM7-lux-Km1 luminescent construct vector was a gracious gift from J. Hardy. Schematics were created with BioRender.com. We thank the lab of G. Gurtner for their advice on the wound infection model. We also thank T. Doyle from the Stanford Center for Innovation in In Vivo Imaging for his technical expertise. This work was supported by grants R21AI133370, R21AI133240, R01AI12492093, and grants from Stanford SPARK, the Falk Medical Research Trust and the Cystic Fibrosis Foundation (CFF) to P.L.B. C.R.D was supported by T32AI007502. A Gabilan Stanford Graduate Fellowship for Science and Engineering and a Lubert Stryer Bio-X Stanford Interdisciplinary Graduate Fellowship supported J.M.S.

All methods described here have been approved by the Institutional Animal Care and Use Committee (IACUC) at Stanford University.
1. Preparation and growth of bacteria
<ol>
	<li>Conduct all work with P. aeruginosa and animals with BSL-2 precautions per the researcher&#39;s institutional biosafety committee and animal use committee guidelines. Do all steps described here involving P. aeruginosa, including mouse inoculation, in a biosafety cabinet.</li>
	<li>The luminescent PA...

<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 and Regeneration. 17 (6), 763-771 (2009).</li><li>Serra, 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=Chronic+wound+infections:+the+role+of+Pseudomonas+aeruginosa+and+Staphylococcus+aureus.">Chronic wound infections: the role of Pseudomonas aeruginosa and Staphylococcus aureus.</a> Expert Review of Anti-infective Therapy. 13 (5), 605-613 (2015).</li><li>Obritsch, M. D., Fish, D. N., MacLaren, R., Jung, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nosocomial+infections+due+to+multidrug-resistant+Pseudomonas+aeruginosa:+epidemiology+and+treatment+options.">Nosocomial infections due to multidrug-resistant Pseudomonas aeruginosa: epidemiology and treatment options.</a> Pharmacotherapy. 25 (10), 1353-1364 (2005).</li><li>Secor, P. 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=Filamentous+Bacteriophage+Produced+by+Pseudomonas+aeruginosa+Alters+the+Inflammatory+Response+and+Promotes+Noninvasive+Infection+In+Vivo.">Filamentous Bacteriophage Produced by Pseudomonas aeruginosa Alters the Inflammatory Response and Promotes Noninvasive Infection In Vivo.</a> Infection and Immunity. 85 (1), (2017).</li><li>Rice, S. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+biofilm+life+cycle+and+virulence+of+Pseudomonas+aeruginosa+are+dependent+on+a+filamentous+prophage.">The biofilm life cycle and virulence of Pseudomonas aeruginosa are dependent on a filamentous prophage.</a> The ISME Journal. 3 (3), 271-282 (2009).</li><li>Bayes, H. K., Ritchie, N., Irvine, S., Evans, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+murine+model+of+early+Pseudomonas+aeruginosa+lung+disease+with+transition+to+chronic+infection.">A murine model of early Pseudomonas aeruginosa lung disease with transition to chronic infection.</a> Scientific Reports. 6, 35838 (2016).</li><li>van Gennip, 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=Interactions+between+polymorphonuclear+leukocytes+and+Pseudomonas+aeruginosa+biofilms+on+silicone+implants+in+vivo.">Interactions between polymorphonuclear leukocytes and Pseudomonas aeruginosa biofilms on silicone implants in vivo.</a> Infection and Immunity. 80 (8), 2601-2607 (2012).</li><li>Tr&#248;strup, 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=Pseudomonas+aeruginosa+biofilm+aggravates+skin+inflammatory+response+in+BALB/c+mice+in+a+novel+chronic+wound+model.">Pseudomonas aeruginosa biofilm aggravates skin inflammatory response in BALB/c mice in a novel chronic wound model.</a> Wound Repair and Regeneration. 21 (2), 292-299 (2013).</li><li>Zhao, 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=Time+course+study+of+delayed+wound+healing+in+a+biofilm-challenged+diabetic+mouse+model.">Time course study of delayed wound healing in a biofilm-challenged diabetic mouse model.</a> Wound Repair and Regeneration. 20 (3), 342-352 (2012).</li><li>Brubaker, A. L., Rendon, J. L., Ramirez, L., Choudhry, M. A., Kovacs, E. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduced+neutrophil+chemotaxis+and+infiltration+contributes+to+delayed+resolution+of+cutaneous+wound+infection+with+advanced+age.">Reduced neutrophil chemotaxis and infiltration contributes to delayed resolution of cutaneous wound infection with advanced age.</a> Journal of Immunolology. 190 (4), 1746-1757 (2013).</li><li>Watters, C., 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=Pseudomonas+aeruginosa+biofilms+perturb+wound+resolution+and+antibiotic+tolerance+in+diabetic+mice.">Pseudomonas aeruginosa biofilms perturb wound resolution and antibiotic tolerance in diabetic mice.</a> Medical Microbiology and Immunology. 202 (2), 131-141 (2013).</li><li>Lee, C., Kerrigan, C. L., Picard-Ami, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclophosphamide-induced+neutropenia:+effect+on+postischemic+skin-flap+survival.">Cyclophosphamide-induced neutropenia: effect on postischemic skin-flap survival.</a> Plastic and Reconstructive Surgery. 89 (6), 1092-1097 (1992).</li><li>Sweere, J. 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=The+immune+response+to+Chronic+Pseudomonas+aeruginosa+wound+infection+in+immunocompetent+mice.">The immune response to Chronic Pseudomonas aeruginosa wound infection in immunocompetent mice.</a> Advances in Wound Care. , (2019).</li><li>Sweere, J. 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=Bacteriophage+trigger+antiviral+immunity+and+prevent+clearance+of+bacterial+infection.">Bacteriophage trigger antiviral immunity and prevent clearance of bacterial infection.</a> Science. 363 (6434), (2019).</li></ol>

We have developed a novel delayed inoculation P. aeruginosa wound infection model. The strategy of delaying inoculation with bacteria until 24 h after excisional wounding enables the evaluation of wound infections over a 1-week timeframe. By using a luminescent strain of P. aeruginosa, it is possible to track infection progression throughout the infection course. The longer course of infection compared to other P. aeruginosa infection models will allow new opportunities for studying host-pathog...

Pseudomonas aeruginosa (P. aeruginosa) is a Gram-negative rod-shaped bacterium with increasing relevance to human health and disease. It is responsible for extensive morbidity and mortality in nosocomial settings, particularly involving wound infections in immunocompromised patients1,2. The emergence of multidrug-resistant strains of this pathogen has provided further impetus for investigation into factors contributing to P. aeruginosa virulence, mechanisms of P. aeruginosa antibiotic resistance, and new methods for prevention and treatment of this deadly infection3. As such, the need for animal models of chronic wound infection as tools for investigating these research questions has never been greater.
Unfortunately, many animal models of P. aeruginosa infection tend to simulate acute infection with rapid resolution of infection or rapid decline due to sepsis4,5, which does not adequately simulate the oftentimes chronic nature of these infections. To address this drawback, some models utilize the implantation of foreign bodies such as agar beads, silicone implants, or alginate gels6,7,8. Other models use mice that are immunocompromised due to advanced age, obesity, or diabetes, or through pharmacological means such as cyclophosphamide-induced neutropenia9,10,11,12. However, either the use of foreign materials or immune compromised hosts likely alters the local inflammatory process, making it difficult to gain an understanding of the pathophysiology involved in chronic wound infections in hosts with otherwise normal immune systems.
We have developed a chronic model of P. aeruginosa wound infection in mice that involves delayed inoculation with bacteria after excisional wounding. Delayed inoculation allows for experiments assessing bacterial burden extending out to at least 7 days. This model opens up new opportunities for investigating both pathogenesis and new treatments of P. aeruginosa chronic infections.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.9% Sodium Chloride injection</td>
			<td>Hospira</td>
			<td>2484457</td>
			<td></td>
		</tr>
		<tr>
			<td>18 G x 1 sterile needle</td>
			<td>BD</td>
			<td>305195</td>
			<td></td>
		</tr>
		<tr>
			<td>25 G x 1 1/5 sterile needle</td>
			<td>BD</td>
			<td>305127</td>
			<td></td>
		</tr>
		<tr>
			<td>Alcohol swab</td>
			<td>BD</td>
			<td>326895</td>
			<td></td>
		</tr>
		<tr>
			<td>Aura Imaging Software</td>
			<td>Spectral Instruments Imaging</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>Betadine</td>
			<td>Purdue Frederick Company</td>
			<td>19-065534</td>
			<td></td>
		</tr>
		<tr>
			<td>Buprenorphine SR LAB</td>
			<td>Zoopharm</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>C57BL/6J male mice</td>
			<td>The Jackson Laboratory</td>
			<td>000664</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable biopsy punch, 6mm</td>
			<td>Integra</td>
			<td>33-36</td>
			<td></td>
		</tr>
		<tr>
			<td>Fine scissors - Tungsten Carbide</td>
			<td>Fine Science Tools</td>
			<td>14568-09</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass Bead Dry Sterilizer</td>
			<td>Harvard Apparatus</td>
			<td>61-0183</td>
			<td></td>
		</tr>
		<tr>
			<td>Granulated Agar</td>
			<td>Fisher BioReagents</td>
			<td>BP9744</td>
			<td></td>
		</tr>
		<tr>
			<td>Heating Pad</td>
			<td>Milliard</td>
			<td>804879481218</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulin syringe with 28 G needle</td>
			<td>BD</td>
			<td>329461</td>
			<td></td>
		</tr>
		<tr>
			<td>Lago X Imaging System</td>
			<td>Spectral Instruments Imaging</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>LB broth</td>
			<td>Fisher BioReagents</td>
			<td>BP1426</td>
			<td></td>
		</tr>
		<tr>
			<td>Leur-Lok 1 mL syringe</td>
			<td>BD</td>
			<td>309628</td>
			<td></td>
		</tr>
		<tr>
			<td>Mini Arco Animal Trimmer</td>
			<td>Wahl Professional</td>
			<td>919152</td>
			<td></td>
		</tr>
		<tr>
			<td>Nair Hair Removal Lotion with Baby Oil</td>
			<td>Church and Dwight</td>
			<td>n/a</td>
			<td>Available at any pharmacy</td>
		</tr>
		<tr>
			<td>Octagon Forceps</td>
			<td>Fine Science Tools</td>
			<td>11041-08</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish</td>
			<td>Falcon</td>
			<td>351029</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline (PBS) 1x</td>
			<td>Corning</td>
			<td>21-040-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Press and Seal Cling Wrap</td>
			<td>Glad</td>
			<td>n/a</td>
			<td></td>
		</tr>
		<tr>
			<td>SafetyGlide Insulin syringe with 30 G needle</td>
			<td>BD</td>
			<td>305934</td>
			<td></td>
		</tr>
		<tr>
			<td>Safetyglide Insulin syringe, 1/2 mL, 30 G x 5/16 TW</td>
			<td>BD</td>
			<td>305934</td>
			<td></td>
		</tr>
		<tr>
			<td>Scale</td>
			<td>Ohaus Scout Pro</td>
			<td>SP202</td>
			<td></td>
		</tr>
		<tr>
			<td>Supplical Nutritional Supplement</td>
			<td>Henry Schein Animal Health</td>
			<td>29908</td>
			<td></td>
		</tr>
		<tr>
			<td>Tegaderm, 6 cm x 7 cm</td>
			<td>3M</td>
			<td>1624W</td>
			<td></td>
		</tr>
	</tbody>
</table>

a delayed inoculation model of chronic pseudomonas aeruginosa wound infection

Pseudomonas aeruginosa (P. aeruginosa) is a major nosocomial pathogen of increasing relevance to human health and disease, particularly in the setting of chronic wound infections in diabetic and hospitalized patients. There is an urgent need for chronic infection models to aid in the investigation of wound pathogenesis and the development of new therapies against this pathogen. Here, we describe a protocol that uses delayed inoculation 24 hours after full-thickness excisional wounding. The infection of the provisional wound matrix present at this time forestalls either rapid clearance or dissemination of infection and instead establishes chronic infection lasting 7&#8211;10 days without the need for implantation of foreign materials or immune suppression. This protocol mimics a typical temporal course of post-operative infection in humans. The use of a luminescent P. aeruginosa strain (PAO1:lux) allows for quantitative daily assessment of bacterial burden for P. aeruginosa wound infections. This novel model may be a useful tool in the investigation of bacterial pathogenesis and the development of new therapies for chronic P. aeruginosa wound infections.

Using a luminescent strain of PAO1 with a plasmid encoding the luxABCDE reporter system (PAO1:lux), we performed excisional wounding on mice, inoculated these wounds with planktonic P. aeruginosa 24 h later, and measured bacterial burden over time (Figure 1 and Figure 2). A representative image obtained using an imaging optical system demonstrates that this model results in detectable luminescence (F...

Watch this Scientific Journal Video about A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection at JoVE.com

A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection (Video) | JoVE

We describe a delayed inoculation protocol for generating chronic wound infections in immunocompetent mice.

A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection

Pseudomonas aeruginosa (P. aeruginosa) is a major nosocomial pathogen of increasing relevance to human health and disease, particularly in the setting of ...

Research

JoVE Journal

Immunology and Infection

Co-culture Models of Pseudomonas aeruginosa Biofilms Grown on Live Human Airway Cells

Co-culture Models of Pseudomonas aeruginosa Biofilms Grown on Live Human Airway Cells (Video) | JoVE

Bacterial biofilms have been associated with a number of different human diseases, but biofilm development has generally been studied on non-living ...

Pseudomonas aeruginosa and Saccharomyces cerevisiae Biofilm in Flow Cells

Pseudomonas aeruginosa and Saccharomyces cerevisiae Biofilm in Flow Cells (Video) | JoVE

Many microbial cells have the ability to form sessile microbial communities defined as biofilms that have altered physiological and pathological ...

RNA Isolation of Pseudomonas aeruginosa Colonizing the Murine Gastrointestinal Tract

RNA Isolation of Pseudomonas aeruginosa Colonizing the Murine Gastrointestinal Tract (Video) | JoVE

Pseudomonas aeruginosa (PA) infections result in significant morbidity and mortality in hosts with compromised immune systems, such as patients with ...

Use of Artificial Sputum Medium to Test Antibiotic Efficacy Against Pseudomonas aeruginosa in Conditions More Relevant to the Cystic Fibrosis Lung

Use of Artificial Sputum Medium to Test Antibiotic Efficacy Against Pseudomonas aeruginosa in Conditions More Relevant to the Cystic Fibrosis Lung (Video) | JoVE

There  is growing concern about the relevance of in vitro antimicrobial  susceptibility tests when applied to isolates of P. aeruginosa from  cystic ...

Long Term Chronic Pseudomonas aeruginosa Airway Infection in Mice

Long Term Chronic Pseudomonas aeruginosa Airway Infection in Mice (Video) | JoVE

A mouse model of chronic airway infection is a key asset in cystic fibrosis (CF) research, although there are a number of concerns regarding the model ...

Pseudomonas aeruginosa Induced Lung Injury Model

Pseudomonas aeruginosa Induced Lung Injury Model (Video) | JoVE

In order to study human acute lung injury and pneumonia, it is important to develop animal models to mimic various pathological features of this disease. ...

Studying Microbial Communities In Vivo: A Model of Host-mediated Interaction Between Candida Albicans and Pseudomonas Aeruginosa in the Airways

Studying Microbial Communities In Vivo: A Model of Host-mediated Interaction Between Candida Albicans and Pseudomonas Aeruginosa in the Airways (Video) | JoVE

Studying host-pathogen interaction enables us to understand the underlying mechanisms of the pathogenicity during microbial infection. The prognosis of ...

Come to the Light Side: In Vivo Monitoring of Pseudomonas aeruginosa Biofilm Infections in Chronic Wounds in a Diabetic Hairless Murine Model

Come to the Light Side: In Vivo Monitoring of Pseudomonas aeruginosa Biofilm Infections in Chronic Wounds in a Diabetic Hairless Murine Model (Video) | JoVE

The presence of bacteria as structured biofilms in chronic wounds, especially in diabetic patients, is thought to prevent wound healing and resolution. ...

Methods for Detecting Cytotoxic Amyloids Following Infection of Pulmonary Endothelial Cells by Pseudomonas aeruginosa

Methods for Detecting Cytotoxic Amyloids Following Infection of Pulmonary Endothelial Cells by Pseudomonas aeruginosa (Video) | JoVE

Patients who survive pneumonia have elevated death rates in the months following hospital discharge. It has been hypothesized that infection of pulmonary ...

Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection

Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection (Video) | JoVE

Microorganisms are genetically versatile and diverse and have become a major source of many commercial products and biopharmaceuticals. Though some of ...