Development of an aerogenous Escherichia coli infection model in adult broiler breeders

AbstractEscherichia coli constitutes an immense challenge to the poultry industry due to its devastating effect on productivity, mortality, and carcass condemnations. To aid future studies on disease mechanisms and interventions, an aerogenous infection model was established in adult broiler breeders. Hens (n = 120) were randomly allocated into six groups receiving either aerosolised E. coli or vehicle, or intratracheal E. coli or vehicle. Replication of aerosol inoculation was performed on distinct days. Alternating euthanasia time points were predetermined in order to evaluate the progression of the disease. All animals were thoroughly necropsied, and bacteriological samples were collected as well as tissues for histopathology. Birds inoculated with E. coli exhibited clinical signs and developed characteristic gross and histopathological lesions of colibacillosis, including splenic fibrinoid necrosis, folliculitis, polyserositis and impaction of parabronchi with fibrinoheterophilic exudate and necrotic debris, as well as positive in situ localisation of intralesional E. coli by immunohistochemistry. This study presents a successful development of a discriminative colibacillosis model through aerosol inoculation of adult broiler breeders. Gross and histopathological lesions characteristic of colibacillosis were established in two independent experiments.

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Protective Potential of an Autogenous Vaccine in an Aerogenous Model of Escherichia coli Infection in Broiler Breeders

Vaccines ◽

10.3390/vaccines9111233 ◽

2021 ◽

Vol 9 (11) ◽

pp. 1233

Author(s):

Sofie Kromann ◽

Rikke Heidemann Olsen ◽

Anders Miki Bojesen ◽

Henrik Elvang Jensen ◽

Ida Thøfner

Keyword(s):

Escherichia Coli ◽

Experimental Models ◽

Vehicle Group ◽

Broiler Breeders ◽

Aerosol Model ◽

Sterile Saline ◽

E Coli ◽

Escherichia Coli Infection ◽

Group A ◽

Autogenous Vaccine

In poultry, Escherichia coli is a common cause of high-cost infections. Consequently, autogenous vaccines are often used despite limited and conflicting evidence on their effectiveness have been presented. The present study aimed to investigate the efficacy of a commonly used autogenous vaccine, previously deemed ineffective, in an aerosol model of colibacillosis. Methods: Broiler breeders (n = 47) were randomly allocated to one of four groups (vaccinated and unvaccinated birds receiving an autogenous vaccine or sterile saline intramuscularly) and challenged with either aerosolised E. coli or vehicle at 29 weeks of age. Two days following inoculation, the birds were euthanised, thoroughly necropsied, and samples for bacteriology and histopathology were collected. Results: Vaccinated birds had a significantly lower bacteriology score compared to the unvaccinated group challenged with E. coli (p < 0.01) and a lower overall air sac lesion score (p < 0.05). Overall lung and spleen lesion scores only differed significantly between the unvaccinated E. coli challenged group compared to the vehicle inoculated groups. The overall gross pathology score was 2.8 and 1.95 in the unvaccinated and vaccinated E. coli challenge groups, respectively, whereas the vaccinated vehicle group had a score of 0.9 and the unvaccinated vehicle group a score of 1. Conclusions: A protective effect of an autogenous vaccine was found utilising an aerogenous model of colibacillosis through multiple methods of evaluation. The findings encourage the continued use of autogenous vaccines and underlines the necessity of discriminative experimental models with high predictive validity when evaluating vaccine interventions.

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Effect of Escherichia Coli Infection on Metabolism of Dietary Protein in Intestine

Current Protein and Peptide Science ◽

10.2174/1389203720666191113144049 ◽

2020 ◽

Vol 21 (8) ◽

pp. 772-776

Author(s):

Xiao-Pei Peng ◽

Wei Ding ◽

Jian-Min Ma ◽

Jie Zhang ◽

Jian Sun ◽

...

Keyword(s):

Escherichia Coli ◽

Intestinal Tract ◽

Effector Proteins ◽

Physical Injury ◽

Dietary Proteins ◽

Pathogenic Role ◽

E Coli ◽

Low Protein ◽

Pathogenic Escherichia Coli ◽

Escherichia Coli Infection

Dietary proteins are linked to the pathogenic Escherichia coli (E. coli) through the intestinal tract, which is the site where both dietary proteins are metabolized and pathogenic E. coli strains play a pathogenic role. Dietary proteins are degraded by enzymes in the intestine lumen and their metabolites are transferred into enterocytes to be further metabolized. Seven diarrheagenic E. coli pathotypes have been identified, and they damage the intestinal epithelium through physical injury and effector proteins, which lead to inhibit the digestibility and absorption of dietary proteins in the intestine tract. But the increased tryptophan (Trp) content in the feed, low-protein diet or milk fractions supplementation is effective in preventing and controlling infections by pathogenic E. coli in the intestine.

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Iron Acquisition of Urinary Tract Infection Escherichia coli Involves Pathogenicity in Caenorhabditis elegans

Microorganisms ◽

10.3390/microorganisms9020310 ◽

2021 ◽

Vol 9 (2) ◽

pp. 310

Author(s):

Masayuki Hashimoto ◽

Yi-Fen Ma ◽

Sin-Tian Wang ◽

Chang-Shi Chen ◽

Ching-Hao Teng

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Caenorhabditis Elegans ◽

Large Scale ◽

Iron Acquisition ◽

Infection Model ◽

High Throughput Analysis ◽

E Coli ◽

C Elegans ◽

Tract Infections

Uropathogenic Escherichia coli (UPEC) is a major bacterial pathogen that causes urinary tract infections (UTIs). The mouse is an available UTI model for studying the pathogenicity; however, Caenorhabditis elegans represents as an alternative surrogate host with the capacity for high-throughput analysis. Then, we established a simple assay for a UPEC infection model with C. elegans for large-scale screening. A total of 133 clinically isolated E. coli strains, which included UTI-associated and fecal isolates, were applied to demonstrate the simple pathogenicity assay. From the screening, several virulence factors (VFs) involved with iron acquisition (chuA, fyuA, and irp2) were significantly associated with high pathogenicity. We then evaluated whether the VFs in UPEC were involved in the pathogenicity. Mutants of E. coli UTI89 with defective iron acquisition systems were applied to a solid killing assay with C. elegans. As a result, the survival rate of C. elegans fed with the mutants significantly increased compared to when fed with the parent strain. The results demonstrated, the simple assay with C. elegans was useful as a UPEC infectious model. To our knowledge, this is the first report of the involvement of iron acquisition in the pathogenicity of UPEC in a C. elegans model.

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Mechanistic insights into synergy between nalidixic acid and tetracycline against clinical isolates of Acinetobacter baumannii and Escherichia coli

Communications Biology ◽

10.1038/s42003-021-02074-5 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Amit Gaurav ◽

Varsha Gupta ◽

Sandeep K. Shrivastava ◽

Ranjana Pathania

Keyword(s):

Escherichia Coli ◽

Acinetobacter Baumannii ◽

Nalidixic Acid ◽

Bacterial Infections ◽

Clinical Isolates ◽

Hospital Environment ◽

Infection Model ◽

Drug Resistant ◽

E Coli

AbstractThe increasing prevalence of antimicrobial resistance has become a global health problem. Acinetobacter baumannii is an important nosocomial pathogen due to its capacity to persist in the hospital environment. It has a high mortality rate and few treatment options. Antibiotic combinations can help to fight multi-drug resistant (MDR) bacterial infections, but they are rarely used in the clinics and mostly unexplored. The interaction between bacteriostatic and bactericidal antibiotics are mostly reported as antagonism based on the results obtained in the susceptible model laboratory strain Escherichia coli. However, in the present study, we report a synergistic interaction between nalidixic acid and tetracycline against clinical multi-drug resistant A. baumannii and E. coli. Here we provide mechanistic insight into this dichotomy. The synergistic combination was studied by checkerboard assay and time-kill curve analysis. We also elucidate the mechanism behind this synergy using several techniques such as fluorescence spectroscopy, flow cytometry, fluorescence microscopy, morphometric analysis, and real-time polymerase chain reaction. Nalidixic acid and tetracycline combination displayed synergy against most of the MDR clinical isolates of A. baumannii and E. coli but not against susceptible isolates. Finally, we demonstrate that this combination is also effective in vivo in an A. baumannii/Caenorhabditis elegans infection model (p < 0.001)

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Biological Cost of Single and Multiple Norfloxacin Resistance Mutations in Escherichia coli Implicated in Urinary Tract Infections

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.6.2343-2351.2005 ◽

2005 ◽

Vol 49 (6) ◽

pp. 2343-2351 ◽

Cited By ~ 91

Author(s):

Patricia Komp Lindgren ◽

Linda L. Marcusson ◽

Dorthe Sandvang ◽

Niels Frimodt-Møller ◽

Diarmaid Hughes

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Infection Model ◽

Resistance Mutations ◽

Topoisomerase Iv ◽

E Coli ◽

Tract Infections ◽

Subsequent Selection

ABSTRACT Resistance to fluoroquinolones in urinary tract infection (UTIs) caused by Escherichia coli is associated with multiple mutations, typically those that alter DNA gyrase and DNA topoisomerase IV and those that regulate AcrAB-TolC-mediated efflux. We asked whether a fitness cost is associated with the accumulation of these multiple mutations. Mutants of the susceptible E. coli UTI isolate Nu14 were selected through three to five successive steps with norfloxacin. Each selection was performed with the MIC of the selected strain. After each selection the MIC was measured; and the regions of gyrA, gyrB, parC, and parE, previously associated with resistance mutations, and all of marOR and acrR were sequenced. The first selection step yielded mutations in gyrA, gyrB, and marOR. Subsequent selection steps yielded mutations in gyrA, parE, and marOR but not in gyrB, parC, or acrR. Resistance-associated mutations were identified in almost all isolates after selection steps 1 and 2 but in less than 50% of isolates after subsequent selection steps. Selected strains were competed in vitro, in urine, and in a mouse UTI infection model against the starting strain, Nu14. First-step mutations were not associated with significant fitness costs. However, the accumulation of three or more resistance-associated mutations was usually associated with a large reduction in biological fitness, both in vitro and in vivo. Interestingly, in some lineages a partial restoration of fitness was associated with the accumulation of additional mutations in late selection steps. We suggest that the relative biological costs of multiple mutations may influence the evolution of E. coli strains that develop resistance to fluoroquinolones.

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Zebrafish nephrosin helps host defence against Escherichia coli infection

Open Biology ◽

10.1098/rsob.170040 ◽

2017 ◽

Vol 7 (8) ◽

pp. 170040 ◽

Cited By ~ 3

Author(s):

Qianqian Di ◽

Qing Lin ◽

Zhibin Huang ◽

Yali Chi ◽

Xiaohui Chen ◽

...

Keyword(s):

Escherichia Coli ◽

Innate Immunity ◽

Host Defence ◽

Bacterial Burden ◽

Wild Type ◽

Lower Survival Rate ◽

E Coli ◽

Escherichia Coli Infection ◽

Effective Models

Neutrophils play important roles in innate immunity and are mainly dependent on various enzyme-containing granules to kill engulfed microorganisms. Zebrafish nephrosin ( npsn ) is specifically expressed in neutrophils; however, its function is largely unknown. Here, we generated an npsn mutant ( npsn smu5 ) via CRISPR/Cas9 to investigate the in vivo function of Npsn. The overall development and number of neutrophils remained unchanged in npsn -deficient mutants, whereas neutrophil antibacterial function was defective. Upon infection with Escherichia coli , the npsn smu5 mutants exhibited a lower survival rate and more severe bacterial burden, as well as augmented inflammatory response to challenge with infection when compared with wild-type embryos, whereas npsn -overexpressing zebrafish exhibited enhanced host defence against E. coli infection. These findings demonstrated that zebrafish Npsn promotes host defence against bacterial infection. Furthermore, our findings suggested that npsn -deficient and -overexpressing zebrafish might serve as effective models of in vivo innate immunity.

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Acute Suppurative Thyroiditis Secondary to Escherichia coli Infection

European Journal of Case Reports in Internal Medicine ◽

10.12890/2021_003009 ◽

2021 ◽

Author(s):

Nida Siddiqui ◽

Nikola Deletic ◽

Frederick Raal ◽

Farzahna Mohamed

Keyword(s):

Escherichia Coli ◽

Suppurative Thyroiditis ◽

Delay In Diagnosis ◽

E Coli ◽

High Clinical Suspicion ◽

Immunodeficiency Virus ◽

Escherichia Coli Infection ◽

Acute Suppurative Thyroiditis ◽

Gram Negative Organisms ◽

Immunocompromised Hosts

Infections of the thyroid gland are rare. Its innate resistance to infections can be attributed to its unique anatomical features and rich blood supply. High clinical suspicion is required as a delay in diagnosis can lead to significant morbidity and mortality. Major pathogens include the Gram-positive Staphylococcus aureus and Streptococcus species; however, Gram-negative organisms have been found especially in immunocompromised hosts. We present a rare case of acute suppurative thyroiditis (AST) secondary to Escherichia coli (E. coli) infection in a woman known to be infected with human immunodeficiency virus (HIV).

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Protective Roles of γδ T Cells and Interleukin-15 in Escherichia coli Infection in Mice

Infection and Immunity ◽

10.1128/iai.66.7.3270-3278.1998 ◽

1998 ◽

Vol 66 (7) ◽

pp. 3270-3278 ◽

Cited By ~ 45

Author(s):

M. Takano ◽

H. Nishimura ◽

Y. Kimura ◽

Y. Mokuno ◽

J. Washizu ◽

...

Keyword(s):

Escherichia Coli ◽

Monoclonal Antibody ◽

T Cells ◽

T Cell Receptor ◽

Host Defense ◽

Γδ T Cells ◽

Cell Receptor ◽

E Coli ◽

Escherichia Coli Infection ◽

Interleukin 15

The number of γδ T cells in the peritoneal cavity was increased after an intraperitoneal (i.p.) infection with Escherichia coli in lipopolysaccharide (LPS)-responsive C3H/HeN mice but not in LPS-hyporesponsive C3H/HeJ mice. The γδ T cells preferentially expressed invariant Vγ6 and Vδ1 chains and proliferated to produce a large amount of gamma interferon in the presence of LPS. Mice depleted of γδ T cells by T-cell receptor δ gene mutation showed impaired resistance against E. coli as assessed by bacterial growth. Macrophages from C3H/HeN mice infected with E. coli expressed higher levels of interleukin-15 (IL-15) mRNA than those from the infected C3H/HeJ mice. Administration of anti-IL-15 monoclonal antibody inhibited, albeit partially, the appearance of γδ T cells in C3H/HeN mice after E. coli infection and diminished the host defense against the infection. These results suggest that LPS-stimulated γδ T cells play an important role in the host defense against E. coli infection and that IL-15 may be partly involved in the protection via an increase in the γδ T cells.

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Improvement of the Enterotoxigenic Escherichia coli Infection Model for Post-Weaning Diarrhea by Controlling for Bacterial Adhesion, Pig Breed and MUC4 Genotype

Veterinary Sciences ◽

10.3390/vetsci7030106 ◽

2020 ◽

Vol 7 (3) ◽

pp. 106

Author(s):

Hiroki Matsumoto ◽

Masashi Miyagawa ◽

Sayaka Takahashi ◽

Ryouichi Shima ◽

Takayuki Oosumi

Keyword(s):

Escherichia Coli ◽

Experimental Infection ◽

Antibacterial Agents ◽

Experimental Models ◽

Enterotoxigenic Escherichia Coli ◽

Infection Model ◽

Swine Industry ◽

Pig Breeds ◽

Adhesion Ability ◽

Escherichia Coli Infection

Enterotoxigenic Escherichia coli (ETEC) is a major cause of post-weaning diarrhea (PWD) in pigs and causes significant damage to the swine industry worldwide. In recent years, there has been increased regulation against the use of antibacterial agents in swine due to their health risks. Utilizing experimental models that consistently recapitulate PWD is important for the development of non-antibacterial agents against PWD in pigs. In this study, we established a highly reproducible PWD infection model by examining differences in adhesion of ETEC to the intestinal tissue as well as the association between MUC4 polymorphisms and sensitivity to PWD. Post-weaning diarrhea differences between pig breeds were also examined. The adhesion to enterocytes varied from 104.0 to 106.4 CFU/mL even among the F4 ETEC strains. Experimental infection revealed that PWD can be induced in all MUC4 genotypes after infection with 1010 CFU/pig of highly adherent ETEC, although there were variable sensitivities between the genotypes. Lowly adherent ETEC did not cause PWD as efficiently as did highly adherent ETEC. The incidence of PWD was confirmed for all pigs with the ETEC-susceptible MUC4 genotypes in all of the breeds. These results indicate that high-precision and reproducible experimental infection is possible regardless of pig breeds by controlling factors on the pig-end (MUC4 genotype) and the bacterial-end (adhesion ability).

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Characterization and Antibiogram of Escherichia coli Associated with Mortality in Broilers and Ducklings in Bangladesh

Bangladesh Journal of Veterinary Medicine ◽

10.3329/bjvm.v2i1.1927 ◽

1970 ◽

Vol 2 (1) ◽

pp. 9-14 ◽

Cited By ~ 1

Author(s):

MT Islam ◽

MA Islam ◽

MA Samad ◽

SML Kabir

Keyword(s):

Escherichia Coli ◽

Antibiotic Sensitivity ◽

High Rate ◽

E Coli ◽

Sensitivity Pattern ◽

Highly Sensitive ◽

Biochemical Studies ◽

Increasing Trend ◽

Escherichia Coli Infection ◽

Hemorrhagic Enteritis

Mortality in broilers (6.56%) and growing ducks (11.0%) caused by Escherichia coli was recorded in the experimental flocks study during the period from May to August 2003. E. coli organisms isolated from broiler birds affected with characteristic lesions of omphalitis and yolk sac infection, fibrinous pericarditis and peri-hepatitis , hemorrhagic enteritis, and accumulation of excessive pericardial and peritoneal fluid, whereas from ducks with lesions of hemorrhagic enteritis and extensive epicardial hemorrhages. Each of the 21 isolates collected from broilers and 11 isolates from ducks was characterized by cultural and biochemical studies, of which 8 isolates from broilers and 5 isolates from ducks were tested for antibiotic sensitivity with 9 different antibiotics. The antibiotic sensitivity pattern showed that the isolates were highly sensitive to ciprofloxacin but an increasing trend of resistance was recorded in broilers (7 / 9) than duck (4 / 9) isolates. It may be concluded from the results of this study that the high rate of E. coli infection in broilers and ducks along with the high resistance of isolates to antibiotics constitute a threat to the poultry industry in Bangladesh. Key words: Escherichia coli infection; mortality; broilers; ducks; characterization; antibiogram doi: 10.3329/bjvm.v2i1.1927 Bangl. J. Vet. Med. (2004). 2 (1) : 09-14

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