Regional Immune Response to Immunization with Escherichia coli O157:H7-Derived Intimin in Cattle

ABSTRACTEscherichia coliO157:H7 is an enteric pathogen of animals and humans that can result in deadly sequelae. Cattle are asymptomatic carriers and shedders of the bacteria and serve as an important reservoir of human infection.E. coliO157:H7 colonizes the gastrointestinal tract, most frequently at the rectoanal junction mucosa in cattle. Vaccination is a potentially highly effective means of decreasing cattle colonization and shedding and thereby decreasing human infections. Currently available vaccines are administered subcutaneously or intramuscularly, and immune responses have been evaluated solely by systemic immunoglobulin responses. This study evaluated local and systemic lymphoproliferative responses in addition to immunoglobulin responses following subcutaneous or mucosal (rectal) immunization withE. coliO157:H7 outer membrane protein intimin over three trials. In all three trials, significant local and systemic lymphoproliferative responses (P< 0.05) occurred following immunization in the majority of animals, as well as significant immunoglobulin responses (P< 0.001) in all animals. Surprisingly, local responses in the mesorectal lymph nodes were very similar between the subcutaneous and mucosal immunization groups. Moreover, the responses in mesorectal lymph nodes appeared targeted rather than generalized, as minimal or no significant responses were observed in the associated prescapular lymph nodes of subcutaneously immunized animals. The results indicate that both subcutaneous and mucosal immunizations are effective methods of inducing immune responses againstE. coliO157:H7 in cattle.

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Fecal Metagenome Sequences from Lactating Dairy Cows Shedding Escherichia coli O157:H7

Microbiology Resource Announcements ◽

10.1128/mra.01279-18 ◽

2018 ◽

Vol 7 (18) ◽

Author(s):

Serajus Salaheen ◽

Seon Woo Kim ◽

Jeffrey S. Karns ◽

Bradd J. Haley ◽

Jo Ann S. Van Kessel

Keyword(s):

Escherichia Coli ◽

Dairy Cows ◽

Causative Agent ◽

Public Domain ◽

Escherichia Coli O157 ◽

Content Type ◽

The Public ◽

E Coli ◽

Lactating Dairy Cows ◽

Human Infections

Cattle are primary reservoirs of Escherichia coli O157:H7, a causative agent of severe human infections. To facilitate analyses of the communities in which this pathogen is found, we sequenced the fecal metagenomes of 10 dairy cows shedding E. coli O157:H7 and added them to the public domain.

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Pathogenic Potential of Emergent Sorbitol-Fermenting Escherichia coli O157:NM

Infection and Immunity ◽

10.1128/iai.01180-08 ◽

2008 ◽

Vol 76 (12) ◽

pp. 5598-5607 ◽

Cited By ~ 39

Author(s):

Tracy Rosser ◽

Tracy Dransfield ◽

Lesley Allison ◽

Mary Hanson ◽

Nicola Holden ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Human Infection ◽

Escherichia Coli O157 ◽

Pathogenic Potential ◽

E Coli ◽

Toxin Exposure ◽

Uremic Syndrome ◽

Human Infections ◽

Main Factor

ABSTRACT Non-sorbitol-fermenting (NSF) Escherichia coli O157:H7 is the primary Shiga toxin-producing E. coli (STEC) serotype associated with human infection. Since 1988, sorbitol-fermenting (SF) STEC O157:NM strains have emerged and have been associated with a higher incidence of progression to hemolytic-uremic syndrome (HUS) than NSF STEC O157:H7. This study investigated bacterial factors that may account for the increased pathogenic potential of SF STEC O157:NM. While no evidence of toxin or toxin expression differences between the two O157 groups was found, the SF STEC O157:NM strains adhered at significantly higher levels to a human colonic cell line. Under the conditions tested, curli were shown to be the main factor responsible for the increased adherence to Caco-2 cells. Notably, 52 of 66 (79%) European SF STEC O157:NM strains tested bound Congo red at 37οC and this correlated with curli expression. In a subset of strains, curli expression was due to increased expression from the csgBAC promoter that was not always a consequence of increased csgD expression. The capacity of SF STEC O157:NM strains to express curli at 37οC may have relevance to the epidemiology of human infections as curliated strains could promote higher levels of colonization and inflammation in the human intestine. In turn, this could lead to increased toxin exposure and an increased likelihood of progression to HUS.

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Comparison between human and animal isolates of Shiga toxin-producing Escherichia coli O157 from Australia

Epidemiology and Infection ◽

10.1017/s0950268801006689 ◽

2002 ◽

Vol 128 (3) ◽

pp. 357-362 ◽

Cited By ~ 17

Author(s):

N. FEGAN ◽

P. DESMARCHELIER

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Human Infection ◽

Pulsed Field Gel Electrophoresis ◽

Toxin Gene ◽

Escherichia Coli O157 ◽

Animal Population ◽

E Coli ◽

Virulence Markers ◽

Animal Isolates

There is very little human disease associated with enterohaemorrhagic Escherichia coli O157 in Australia even though these organisms are present in the animal population. A group of Australian isolates of E. coli O157:H7 and O157:H- from human and animal sources were tested for the presence of virulence markers and compared by XbaI DNA macrorestriction analysis using pulsed-field gel electrophoresis (PFGE). Each of 102 isolates tested contained the gene eae which encodes the E. coli attaching and effacing factor and all but one carried the enterohaemolysin gene, ehxA, found on the EHEC plasmid. The most common Shiga toxin gene carried was stx2c, either alone (16%) or in combination with stx1 (74%) or stx2 (3%). PFGE grouped the isolates based on H serotype and some clusters were source specific. Australian E. coli O157:H7 and H- isolates from human, animal and meat sources carry all the virulence markers associated with EHEC disease in humans therefore other factors must be responsible for the low rates of human infection in Australia.

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Effect of Cattle Diet on Escherichia coli O157:H7 Acid Resistance

Applied and Environmental Microbiology ◽

10.1128/aem.65.7.3233-3235.1999 ◽

1999 ◽

Vol 65 (7) ◽

pp. 3233-3235 ◽

Cited By ~ 110

Author(s):

Carolyn J. Hovde ◽

Paula R. Austin ◽

Karen A. Cloud ◽

Christopher J. Williams ◽

Carl W. Hunt

Keyword(s):

Escherichia Coli ◽

Acid Resistance ◽

Escherichia Coli O157 ◽

E Coli ◽

Human Infections

ABSTRACT The duration of shedding of Escherichia coli O157 isolates by hay-fed and grain-fed steers experimentally inoculated withE. coli O157:H7 was compared, as well as the acid resistance of the bacteria. The hay-fed animals shed E. coli O157 longer than the grain-fed animals, and irrespective of diet, these bacteria were equally acid resistant. Feeding cattle hay may increase human infections with E. coli O157:H7.

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Escherichia coli O157[ratio ]H7 infection of calves: infectious dose and direct contact transmission

Epidemiology and Infection ◽

10.1017/s095026880100615x ◽

2001 ◽

Vol 127 (3) ◽

pp. 555-560 ◽

Cited By ~ 92

Author(s):

T. E. BESSER ◽

B. L. RICHARDS ◽

D. H. RICE ◽

D. D. HANCOCK

Keyword(s):

Escherichia Coli ◽

Direct Contact ◽

Reservoir Host ◽

Human Infection ◽

Escherichia Coli O157 ◽

Faecal Excretion ◽

Infectious Dose ◽

E Coli ◽

Electrophoretic Patterns ◽

Contact Transmission

Cattle are considered to be a reservoir host of Escherichia coli O157[ratio ]H7 and contaminated foods of bovine origin are important vehicles of human infection. In this study, the susceptibility of calves to experimental E. coli O157[ratio ]H7 infection following low oral exposures was determined. Two of 17 calves exposed to very low (<300 c.f.u.) doses, and 3 of 4 calves exposed to low (<10000 c.f.u.) doses, subsequently excreted the challenge strains in their faeces. All calves (n = 12) sharing isolation rooms with calves that excreted the challenge strain in their faeces similarly began faecal excretion of the same strains within 21 days or less. The identity between the challenge strains and the strains excreted in calf faeces was confirmed by restriction digestion electrophoretic patterns using pulsed field gel electrophoresis. Calves shed E. coli O157[ratio ]H7 in their faeces after very low dose exposures at concentrations ranging from <30 to >107 c.f.u./g, and for durations similar to the values previously reported for calves challenged by larger doses. The susceptibility of calves to infection following very low exposures or direct contact with infected calves has important implications for programmes for pre-harvest control of this agent.

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Molecular Epidemiology and Genome Dynamics of New Delhi Metallo-β-Lactamase-Producing Extraintestinal Pathogenic Escherichia coli Strains from India

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01345-16 ◽

2016 ◽

Vol 60 (11) ◽

pp. 6795-6805 ◽

Cited By ~ 32

Author(s):

Amit Ranjan ◽

Sabiha Shaik ◽

Agnismita Mondal ◽

Nishant Nandanwar ◽

Arif Hussain ◽

...

Keyword(s):

Escherichia Coli ◽

Effective Means ◽

Genomic Analysis ◽

Virulence Gene ◽

Carbapenem Resistance ◽

Control Measures ◽

Large Sample Size ◽

Gene Repertoire ◽

Content Type ◽

E Coli

ABSTRACTThe global dissemination and increasing incidence of carbapenem-resistant, Gram-negative organisms have resulted in acute public health concerns. Here, we present a retrospective multicenter study on molecular characterization of metallo-β-lactamase (MBL)-producing clinicalEscherichia coliisolates recovered from extraintestinal infections in two hospitals in Pune, India. We screened a large sample size of 510E. coliisolates for MBL production wherein we profiled their molecular determinants, antimicrobial resistance phenotypes, functional virulence properties, genomic features, and transmission dynamics. Approximately 8% of these isolates were MBL producers, the majority of which were of the NDM-1 (69%) type, followed by NDM-5 (19%), NDM-4 (5.5%), and NDM-7 (5.5%). MBL producers were resistant to all antibiotics tested except for colistin, fosfomycin, and chloramphenicol, which were effective to various extents. Plasmids were found to be an effective means of dissemination of NDM genes and other resistance traits. All MBL producers adhered to and invaded bladder epithelial (T24) cells and demonstrated significant serum resistance. Genomic analysis of MBL-producingE. coliisolates revealed higher resistance but a moderate virulence gene repertoire. A subset of NDM-1-positiveE. coliisolates was identified as dominant sequence type 101 (ST101) while two strains belonging to ST167 and ST405 harbored NDM-5. A majority of MBL-producingE. colistrains revealed unique genotypes, suggesting that they were clonally unrelated. Overall, the coexistence of virulence and carbapenem resistance in clinicalE. coliisolates is of serious concern. Moreover, the emergence of NDM-1 among the globally dominantE. coliST101 isolates warrants stringent surveillance and control measures.

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Inflammation-Induced Acid Tolerance GenesgadABin Luminal Commensal Escherichia coli Attenuate Experimental Colitis

Infection and Immunity ◽

10.1128/iai.00355-13 ◽

2013 ◽

Vol 81 (10) ◽

pp. 3662-3671 ◽

Cited By ~ 17

Author(s):

Sandrine Tchaptchet ◽

Ting-Jia Fan ◽

Laura Goeser ◽

Alexi Schoenborn ◽

Ajay S. Gulati ◽

...

Keyword(s):

Escherichia Coli ◽

Immune Responses ◽

Intestinal Inflammation ◽

Intestinal Epithelial Cells ◽

Acid Tolerance ◽

Experimental Colitis ◽

Intestinal Epithelial ◽

Content Type ◽

E Coli ◽

Chronic Intestinal Inflammation

ABSTRACTDysregulated immune responses to commensal intestinal bacteria, includingEscherichia coli, contribute to the development of inflammatory bowel diseases (IBDs) and experimental colitis. Reciprocally,E. coliresponds to chronic intestinal inflammation by upregulating expression of stress response genes, includinggadAandgadB. GadAB encode glutamate decarboxylase and protectE. colifrom the toxic effects of low pH and fermentation acids, factors present in the intestinal lumen in patients with active IBDs. We hypothesized thatE. coliupregulatesgadABduring inflammation to enhance its survival and virulence. Using real-time PCR, we determinedgadABexpression in luminalE. colifrom ex-germfree wild-type (WT) and interleukin-10 (IL-10) knockout (KO) (IL-10−/−) mice selectively colonized with a commensalE. coliisolate (NC101) that causes colitis in KO mice in isolation or in combination with 7 other commensal intestinal bacterial strains.E. colisurvival and host inflammatory responses were measured in WT and KO mice colonized with NC101 or a mutant lacking thegadABgenes (NC101ΔgadAB). The susceptibility of NC101 and NC101ΔgadABto killing by host antimicrobial peptides and their translocation across intestinal epithelial cells were evaluated using bacterial killing assays and transwell experiments, respectively. We show that expression ofgadABin luminalE. coliincreases proportionately with intestinal inflammation in KO mice and enhances the susceptibility of NC101 to killing by the host antimicrobial peptide cryptdin-4 but decreases bacterial transmigration across intestinal epithelial cells, colonic inflammation, and mucosal immune responses. Chronic intestinal inflammation upregulates acid tolerance pathways in commensalE. coliisolates, which, contrary to our original hypothesis, limits their survival and colitogenic potential. Further investigation of microbial adaptation to immune-mediated inflammation may provide novel insights into the pathogenesis and treatment of IBDs.

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Use of In Vivo-Induced Antigen Technology for Identification of Escherichia coli O157:H7 Proteins Expressed during Human Infection

Infection and Immunity ◽

10.1128/iai.73.5.2665-2679.2005 ◽

2005 ◽

Vol 73 (5) ◽

pp. 2665-2679 ◽

Cited By ~ 48

Author(s):

Manohar John ◽

Indira T. Kudva ◽

Robert W. Griffin ◽

Allen W. Dodson ◽

Bethany McManus ◽

...

Keyword(s):

Escherichia Coli ◽

Vaccine Development ◽

Human Infection ◽

Escherichia Coli O157 ◽

Standard Laboratory ◽

E Coli ◽

Phase Culture ◽

Stool Specimens

ABSTRACT Using in vivo-induced antigen technology (IVIAT), a modified immunoscreening technique that circumvents the need for animal models, we directly identified immunogenic Escherichia coli O157:H7 (O157) proteins expressed either specifically during human infection but not during growth under standard laboratory conditions or at significantly higher levels in vivo than in vitro. IVIAT identified 223 O157 proteins expressed during human infection, several of which were unique to this study. These in vivo-induced (ivi) proteins, encoded by ivi genes, mapped to the backbone, O islands (OIs), and pO157. Lack of in vitro expression of O157-specific ivi proteins was confirmed by proteomic analysis of a mid-exponential-phase culture of E. coli O157 grown in LB broth. Because ivi proteins are expressed in response to specific cues during infection and might help pathogens adapt to and counter hostile in vivo environments, those identified in this study are potential targets for drug and vaccine development. Also, such proteins may be exploited as markers of O157 infection in stool specimens.

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Salmonella and Escherichia coli O157:H7 Survival in Soil and Translocation into Leeks (Allium porrum) as Influenced by an Arbuscular Mycorrhizal Fungus (Glomus intraradices)

Applied and Environmental Microbiology ◽

10.1128/aem.02855-12 ◽

2013 ◽

Vol 79 (6) ◽

pp. 1813-1820 ◽

Cited By ~ 13

Author(s):

Joshua B. Gurtler ◽

David D. Douds ◽

Brian P. Dirks ◽

Jennifer J. Quinlan ◽

April M. Nicholson ◽

...

Keyword(s):

Escherichia Coli ◽

Glomus Intraradices ◽

Mycorrhizal Fungus ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Allium Porrum ◽

Escherichia Coli O157 ◽

Content Type ◽

E Coli ◽

The Mean

ABSTRACTA study was conducted to determine the influence of arbuscular mycorrhizal (AM) fungi onSalmonellaand enterohemorrhagicEscherichia coliO157:H7 (EHEC) in autoclaved soil and translocation into leek plants. Six-week-old leek plants (with [Myc+] or without [Myc−] AM fungi) were inoculated with composite suspensions ofSalmonellaor EHEC at ca. 8.2 log CFU/plant into soil. Soil, root, and shoot samples were analyzed for pathogens on days 1, 8, 15, and 22 postinoculation. Initial populations (day 1) were ca. 3.1 and 2.1 log CFU/root, ca. 2.0 and 1.5 log CFU/shoot, and ca. 5.5 and 5.1 CFU/g of soil forSalmonellaand EHEC, respectively. Enrichments indicated that at days 8 and 22, only 31% of root samples were positive for EHEC, versus 73% positive forSalmonella. The meanSalmonellalevel in soil was 3.4 log CFU/g at day 22, while EHEC populations dropped to ≤0.75 log CFU/g by day 15. Overall,Salmonellasurvived in a greater number of shoot, root, and soil samples, compared with the survival of EHEC. EHEC was not present in Myc− shoots after day 8 (0/16 samples positive); however, EHEC persisted in higher numbers (P= 0.05) in Myc+ shoots (4/16 positive) at days 15 and 22.Salmonella, likewise, survived in statistically higher numbers of Myc+ shoot samples (8/8) at day 8, compared with survival in Myc− shoots (i.e., only 4/8). These results suggest that AM fungi may potentially enhance the survival ofE. coliO157:H7 andSalmonellain the stems of growing leek plants.

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Physical Covering for Control of Escherichia coli O157:H7 and Salmonella spp. in Static and Windrow Composting Processes

Applied and Environmental Microbiology ◽

10.1128/aem.04002-14 ◽

2015 ◽

Vol 81 (6) ◽

pp. 2063-2074 ◽

Cited By ~ 7

Author(s):

Jitendra R. Patel ◽

Irene Yossa ◽

Dumitru Macarisin ◽

Patricia Millner

Keyword(s):

Escherichia Coli ◽

Escherichia Coli O157 ◽

Bacterial Reduction ◽

Salmonella Spp ◽

Rapid Reduction ◽

Content Type ◽

E Coli ◽

Windrow Composting ◽

Composting Systems ◽

Feedstock Material

ABSTRACTThis study investigated the effect of a 30-cm covering of finished compost (FC) on survival ofEscherichia coliO157:H7 andSalmonellaspp. in active static and windrow composting systems. Feedstocks inoculated withE. coliO157:H7 (7.41 log CFU/g) andSalmonella(6.46 log CFU/g) were placed in biosentry tubes (7.5-cm diameter, 30-cm height) at three locations: (i and ii) two opposing sides at the interface between the FC cover layer (where present) and the feedstock material (each positioned approximately 10 cm below the pile's surface) and (iii) an internal location (top) (approximately 30 cm below the surface). On specific sampling days, surviving populations of inoculatedE. coliO157:H7 andSalmonella, genericE. coli, and coliforms in compost samples were determined.Salmonellaspp. were reduced significantly within 24 h in windrow piles and were below the detection limit after 3 and 7 days at internal locations of windrow and static piles containing FC covering, respectively. Likewise,E. coliO157:H7 was undetectable after 1 day in windrow piles covered with finished compost. Use of FC as a covering layer significantly increased the number of days that temperatures in the windrows remained ≥55°C at all locations and in static piles at internal locations. These time-temperature exposures resulted in rapid reduction of inoculated pathogens, and the rate of bacterial reduction was rapid in windrow piles. The sample location significantly influenced the survival of these pathogens at internal locations compared to that at interface locations of piles. Finished compost covering of compost piles aids in the reduction of pathogens during the composting process.

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