scholarly journals An oral inoculation infant rabbit model for Shigella infection

2019 ◽  
Author(s):  
Carole J. Kuehl ◽  
Jonathan D. D’Gama ◽  
Alyson R. Warr ◽  
Matthew K. Waldor
Keyword(s):  
Animal Models ◽  
Type Iii Secretion ◽  
Diarrheal Disease ◽  
Small Animal ◽  
Oral Route ◽  
Oral Infection ◽  
Secretion System ◽  
Colonic Epithelium ◽  
Intestinal Colonization ◽  
Small Animal Models

AbstractShigella species cause diarrheal disease globally. Shigellosis is typically characterized by bloody stools and colitis with mucosal damage and is the leading bacterial cause of diarrheal death worldwide. Following oral ingestion, the pathogen invades and replicates within the colonic epithelium through mechanisms that rely on its type III secretion system (T3SS). Currently, oral infection-based small animal models to study the pathogenesis of shigellosis are lacking. Here, we found that oro-gastric inoculation of infant rabbits with S. flexneri resulted in diarrhea and colonic pathology resembling that found in human shigellosis. Fasting animals prior to S. flexneri inoculation increased the frequency of disease. The pathogen colonized the colon, where both luminal and intraepithelial foci were observed. The intraepithelial foci likely arise through S. flexneri spreading from cell-to-cell. Robust S. flexneri intestinal colonization, invasion of the colonic epithelium, and epithelial sloughing all required the T3SS as well as IcsA, a factor required for bacterial spreading and adhesion in vitro. Expression of the proinflammatory chemokine IL-8, detected with in situ mRNA labeling, was higher in animals infected with wild-type S. flexneri versus mutant strains deficient in icsA or T3SS, suggesting that epithelial invasion promotes expression of this chemokine. Collectively, our findings suggest that oral infection of infant rabbits offers a useful experimental model for studies of the pathogenesis of shigellosis and for testing of new therapeutics.ImportanceShigella species are the leading bacterial cause of diarrheal death globally. The pathogen causes bacillary dysentery, a bloody diarrheal disease characterized by damage to the colonic mucosa and is usually spread through the fecal-oral route. Small animal models of shigellosis that rely on the oral route of infection are lacking. Here, we found that oro-gastric inoculation of infant rabbits with S. flexneri led to a diarrheal disease and colonic pathology reminiscent of human shigellosis. Diarrhea, intestinal colonization and pathology in this model were dependent on the S. flexneri type III secretion system and IcsA, canonical Shigella virulence factors. Thus, oral infection of infant rabbits offers a feasible model to study the pathogenesis of shigellosis and to develop and test new therapeutics.

scholarly journals An Oral Inoculation Infant Rabbit Model for Shigella Infection

mBio ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Carole J. Kuehl ◽  
Jonathan D. D’Gama ◽  
Alyson R. Warr ◽  
Matthew K. Waldor
Keyword(s):  
Type Iii Secretion ◽  
Diarrheal Disease ◽  
Small Animal ◽  
Oral Route ◽  
Oral Infection ◽  
Secretion System ◽  
Colonic Epithelium ◽  
Intestinal Colonization ◽  
Content Type ◽  
Small Animal Models

ABSTRACT Shigella species cause diarrheal disease globally. Shigellosis is typically characterized by bloody stools and colitis with mucosal damage and is the leading bacterial cause of diarrheal death worldwide. After the pathogen is orally ingested, it invades and replicates within the colonic epithelium through mechanisms that rely on its type III secretion system (T3SS). Currently, oral infection-based small animal models to study the pathogenesis of shigellosis are lacking. Here, we found that orogastric inoculation of infant rabbits with Shigella flexneri resulted in diarrhea and colonic pathology resembling that found in human shigellosis. Fasting animals prior to S. flexneri inoculation increased the frequency of disease. The pathogen colonized the colon, where both luminal and intraepithelial foci were observed. The intraepithelial foci likely arise through S. flexneri spreading from cell to cell. Robust S. flexneri intestinal colonization, invasion of the colonic epithelium, and epithelial sloughing all required the T3SS as well as IcsA, a factor required for bacterial spreading and adhesion in vitro. Expression of the proinflammatory chemokine interleukin 8 (IL-8), detected with in situ mRNA labeling, was higher in animals infected with wild-type S. flexneri versus mutant strains deficient in icsA or T3SS, suggesting that epithelial invasion promotes expression of this chemokine. Collectively, our findings suggest that oral infection of infant rabbits offers a useful experimental model for studies of the pathogenesis of shigellosis and for testing of new therapeutics. IMPORTANCE Shigella species are the leading bacterial cause of diarrheal death globally. The pathogen causes bacillary dysentery, a bloody diarrheal disease characterized by damage to the colonic mucosa and is usually spread through the fecal-oral route. Small animal models of shigellosis that rely on the oral route of infection are lacking. Here, we found that orogastric inoculation of infant rabbits with S. flexneri led to a diarrheal disease and colonic pathology reminiscent of human shigellosis. Diarrhea, intestinal colonization, and pathology in this model were dependent on the S. flexneri type III secretion system and IcsA, canonical Shigella virulence factors. Thus, oral infection of infant rabbits offers a feasible model to study the pathogenesis of shigellosis and to develop and test new therapeutics.

Abstract 228: Alterations of Cardiac Morphology and Function Caused by Cardio-Thoracic Surgery in Small Animal Models of Heart Disease

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Peter Nordbeck ◽  
Leoni Bönhof ◽  
Karl-Heinz Hiller ◽  
Sabine Voll ◽  
Paula Arias ◽  
...  
Keyword(s):  
Body Weight ◽  
Heart Disease ◽  
Animal Models ◽  
Right Ventricular ◽  
Small Animal ◽  
Cardiac Morphology ◽  
Small Animal Models ◽  
And Function

Background: Surgical procedures in small animal models of heart disease, such as artificial ligation of the coronary arteries for experimental myocardial infarction, can evoke alterations in cardiac morphology and function. Such alterations might induce artificial early or long term effects in vivo that might account for a significant bias in basic cardiovascular research, and, therefore, could potentially question the meaning of respective studies in small animal models of heart disease. Methods: Female Wistar rats were matched for weight and distributed to sham left coronary artery ligation or untreated control. Cardiac parameters were then investigated in vivo by high-field MRI over time after the surgical procedure, determining left and right ventricular morphology and function. Additionally, the time course of several metabolic and inflammatory blood parameters was determined. Results: Rats after sham surgery showed a lower body weight for up to 8 weeks after the intervention compared to healthy controls. Left and right ventricular morphology and function were not different in absolute measures in both groups 1 week after surgery. However, there was a confined difference in several cardiac parameters normalized to the body weight (bw), such as myocardial mass (2.19±0.30/0.83±0.13 vs. 1.85±0.22/0.70±0.07 mg left/right per g bw, p<0.05), or enddiastolic ventricular volume (1.31±0.36/1.21±0.31 vs. 1.14±0.20/1.07±0.17 µl left/right per g bw, p<0.05). Vice versa, after 8 weeks, cardiac masses, volumes, and output showed a trend for lower values in the sham operated rats compared to the controls in absolute measures (782.2±57.2/260.2±33.2 vs. 805.9±84.8/310.4±48.5 mg, p<0.05 for left/right ventricular mass), but not normalized to body weight. Matching these findings, blood testing revealed prolonged metabolic and inflammatory changes after surgery not related to cardiac disease. Conclusion: There is a small distinct impact of cardio-thoracic surgical procedures on the global integrity of the organism, which in the long term also includes circumscribed repercussions on cardiac morphology and function. This impact has to be considered when analyzing data from respective studies and transferring the findings to conditions in patients.

scholarly journals Small Animal Models of Heart Failure

2009 ◽  
Vol 2 (2) ◽  
pp. 138-144 ◽  
Author(s):  
Richard D. Patten ◽  
Monica R. Hall-Porter
Keyword(s):  
Heart Failure ◽  
Animal Models ◽  
Small Animal ◽  
Small Animal Models

scholarly journals Neuromuscular Development and Disease: Learning From in vitro and in vivo Models

2021 ◽  
Vol 9 ◽  
Author(s):  
Zachary Fralish ◽  
Ethan M. Lotz ◽  
Taylor Chavez ◽  
Alastair Khodabukus ◽  
Nenad Bursac
Keyword(s):  
Skeletal Muscle ◽  
Cell Culture ◽  
Animal Models ◽  
Schwann Cells ◽  
Motor Neurons ◽  
Small Animal ◽  
In Vivo Models ◽  
Small Animal Models

The neuromuscular junction (NMJ) is a specialized cholinergic synaptic interface between a motor neuron and a skeletal muscle fiber that translates presynaptic electrical impulses into motor function. NMJ formation and maintenance require tightly regulated signaling and cellular communication among motor neurons, myogenic cells, and Schwann cells. Neuromuscular diseases (NMDs) can result in loss of NMJ function and motor input leading to paralysis or even death. Although small animal models have been instrumental in advancing our understanding of the NMJ structure and function, the complexities of studying this multi-tissue system in vivo and poor clinical outcomes of candidate therapies developed in small animal models has driven the need for in vitro models of functional human NMJ to complement animal studies. In this review, we discuss prevailing models of NMDs and highlight the current progress and ongoing challenges in developing human iPSC-derived (hiPSC) 3D cell culture models of functional NMJs. We first review in vivo development of motor neurons, skeletal muscle, Schwann cells, and the NMJ alongside current methods for directing the differentiation of relevant cell types from hiPSCs. We further compare the efficacy of modeling NMDs in animals and human cell culture systems in the context of five NMDs: amyotrophic lateral sclerosis, myasthenia gravis, Duchenne muscular dystrophy, myotonic dystrophy, and Pompe disease. Finally, we discuss further work necessary for hiPSC-derived NMJ models to function as effective personalized NMD platforms.

scholarly journals Translational Animal Models for Liver Cancer

2018 ◽  
Vol 2 ◽  
pp. 2 ◽  
Author(s):  
Michele Obeid ◽  
Ramzy C. Khabbaz ◽  
Kelly D. Garcia ◽  
Kyle M. Schachtschneider ◽  
Ron C. Gaba
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cancer Research ◽  
Animal Models ◽  
Liver Cancer ◽  
Small Animal ◽  
Large Animal ◽  
Starting Point ◽  
Perfect Model ◽  
Small Animal Models ◽  
Human Primate

Animal models have become increasingly important in the study of hepatocellular carcinoma (HCC), as they serve as a critical bridge between laboratory-based discoveries and human clinical trials. Developing an ideal animal model for translational use is challenging, as the perfect model must be able to reproduce human disease genetically, anatomically, physiologically, and pathologically. This brief review provides an overview of the animal models currently available for translational liver cancer research, including rodent, rabbit, non-human primate, and pig models, with a focus on their respective benefits and shortcomings. While small animal models offer a solid starting point for investigation, large animal HCC models are becoming increasingly important for translation of preclinical results to clinical practice.

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