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Tamaki Y, Harakuni T, Arakawa T. Shiga toxin type 2 B subunit protects mice against toxin challenge when leashed and bundled by a stable pentameric coiled-coil molecule. Vaccine 2024; 42:1757-1767. [PMID: 38365487 DOI: 10.1016/j.vaccine.2024.01.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 11/27/2023] [Accepted: 01/30/2024] [Indexed: 02/18/2024]
Abstract
Vaccines against Shiga toxin (Stx)-producing Escherichia coli (STEC) have not yet been developed. Two immunologically distinct serotypes of Stx (Stx1 and Stx2) are the main virulence factors of STEC. Thus, blocking their B subunits (StxB) from binding to the cell surface receptor globotriaosylceramide (Gb3) efficiently prevents the action of these toxins. We expressed Stx1B and Stx2B in E. coli inclusion bodies and reassembled them into pentamers by a stepwise dialysis. Stx1B pentamer fully protected mice against Stx1 challenge, but Stx2B pentamer failed to protect mice against Stx2 challenge. To explain those observations, we proposed that the pentamer of Stx2B readily dissociates into its constituent monomers, especially under in vivo conditions, thus being unable to induce pentamer-specific immunity. To increase pentamer stability, we fused the B subunit to a pentameric coiled-coil domain of the cartilage oligomeric matrix protein (COMP). This "five-to-five" fusion hybrid molecule (Stx2B-COMP) was shown to be protective against Stx2 challenge, demonstrating that the Stx2B subunit when leashed and bundled by a rigid pentameric coiled-coil domain mount a pentamer-specific immune response and efficiently neutralize the toxin both in vitro and in vivo. Our data strongly suggest that the Stx2B subunit moiety fluctuates between a pentameric and monomeric state within the fusion protein, which may increase the likelihood of the immune system recognizing the pentameric conformation for toxin neutralization.
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Affiliation(s)
- Yukihiro Tamaki
- Laboratory of Vaccine Research and Development, Center of Molecular Biosciences, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
| | - Tetsuya Harakuni
- Laboratory of Vaccine Research and Development, Center of Molecular Biosciences, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
| | - Takeshi Arakawa
- Laboratory of Vaccine Research and Development, Center of Molecular Biosciences, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan.
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2
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Kirkland ME, Patfield S, Hughes AC, Hernlem B, He X. A novel Shiga toxin 2a neutralizing antibody therapeutic with low immunogenicity and high efficacy. Antimicrob Agents Chemother 2024; 68:e0059823. [PMID: 38047751 PMCID: PMC10777836 DOI: 10.1128/aac.00598-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 10/18/2023] [Indexed: 12/05/2023] Open
Abstract
Shiga toxin-producing Escherichia coli infections are difficult to treat due to the risk of antibiotic-induced stress upregulating the production of toxins, medical treatment is consequently limited to supportive care to prevent the development of hemolytic uremic syndrome (HUS). Here, we introduce a potentially therapeutic humanized mouse monoclonal antibody (Hu-mAb 2-5) targeting Stx2a, the most common Shiga toxin subtype identified from outbreaks. We demonstrate that Hu-mAb 2-5 has low immunogenicity in healthy adults ex vivo and high neutralizing efficacy in vivo, protecting mice from mortality and HUS-related tissue damage.
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Affiliation(s)
- Marina E. Kirkland
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
- U.S. Department of Energy, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA
| | - Stephanie Patfield
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
| | - Anna C. Hughes
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
| | - Bradley Hernlem
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
| | - Xiaohua He
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
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3
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Zaki MS, Abd-El-All AM, Attia AS, Dahshan H, Al-Ashery MA, Megahed A. Escherichia coli and Salmonella enterica isolated from Egyptian dairy cattle herds: The prevalence and molecular characteristics. Open Vet J 2024; 14:214-224. [PMID: 38633193 PMCID: PMC11018409 DOI: 10.5455/ovj.2024.v14.i1.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 12/15/2023] [Indexed: 04/19/2024] Open
Abstract
Background The pathogens Escherichia coli and Salmonella enterica that caused substantial health problems and financial losses were believed to have originated primarily from Egypt's dairy farms. Aim The purpose of this study was to ascertain the occurrence of E. coli and S. enterica in three large dairy farms located in the Egyptian governorate of Sharkia. Furthermore, biochemical and serological characteristics of the isolated isolates were described. Further analysis revealed that several E. coli serovars had the genes stx1, stx2, eaeA, and hylA, while invA, stn, and hilA genes were found in several S. enterica serotypes using a multi-plex PCR. Methods A total of 540 samples of fresh raw cow milk, water, feedstuffs, feces, (108 each), as well as swabs from feeders, milker hands and cattle crushes (36 each ), were gathered and analyzed. Results The recovery of E. coli from various sampling sources was shown to have an overall prevalence of 62.2% (336/540) in the results. Fecal samples had isolated S. enterica, with a frequency of 0.74% (4/540). The existence of various groups of serovars, such as O26, O44, O55, O78 and O111 for E. coli and Salmonella enteritidis, Salmonella typhimurium and Salmonella inganda for S. enterica was revealed by serological identification of the two species. However, it was discovered that a number of E. coli serovars had much higher percentages of the eaeA and hylA genes as well as shiga-toxin types 1 and 2 (stx1 and stx2). The presence of the invA gene, a diagnostic marker for S. enterica was 100% across all serovars. Salmonella enteritidis possessed both the enterotoxin gene (stn) and the hyper-invasive locus gene (hilA). Salmonella typhimurium had the hilA gene, whereas S. inganda had the stn gene. Conclusion Escherichia coli and S. enterica recovered in this study have significant genetic risk factors for high pathogenicity and virulence, posing a real threat to dairy population productivity and health, which could spread to the general public through milk.
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Affiliation(s)
- Mahmoud S.A. Zaki
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Amr M.M. Abd-El-All
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Amira S.A. Attia
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Hesham Dahshan
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Manal A. Al-Ashery
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Ayman Megahed
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
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Sedhom J, Solomon LA. Lambda CI Binding to Related Phage Operator Sequences Validates Alignment Algorithm and Highlights the Importance of Overlooked Bonds. Genes (Basel) 2023; 14:2221. [PMID: 38137043 PMCID: PMC10742460 DOI: 10.3390/genes14122221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 12/24/2023] Open
Abstract
Bacteriophage λ's CI repressor protein controls a genetic switch between the virus's lysogenic and lytic lifecycles, in part, by selectively binding to six different DNA sequences within the phage genome-collectively referred to as operator sites. However, the minimal level of information needed for CI to recognize and specifically bind these six unique-but-related sequences is unclear. In a previous study, we introduced an algorithm that extracts the minimal direct readout information needed for λ-CI to recognize and bind its six binding sites. We further revealed direct readout information shared among three evolutionarily related lambdoid phages: λ-phage, Enterobacteria phage VT2-Sakai, and Stx2 converting phage I, suggesting that the λ-CI protein could bind to the operator sites of these other phages. In this study, we show that λ-CI can indeed bind the other two phages' cognate binding sites as predicted using our algorithm, validating the hypotheses from that paper. We go on to demonstrate the importance of specific hydrogen bond donors and acceptors that are maintained despite changes to the nucleobase itself, and another that has an important role in recognition and binding. This in vitro validation of our algorithm supports its use as a tool to predict alternative binding sites for DNA-binding proteins.
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Affiliation(s)
| | - Lee A. Solomon
- Department of Chemistry and Biochemistry, George Mason University, Fairfax, VA 22030, USA;
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5
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Neu C, Wissuwa B, Thiemermann C, Coldewey SM. Cardiovascular impairment in Shiga-toxin-2-induced experimental hemolytic-uremic syndrome: a pilot study. Front Immunol 2023; 14:1252818. [PMID: 37809105 PMCID: PMC10556238 DOI: 10.3389/fimmu.2023.1252818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/01/2023] [Indexed: 10/10/2023] Open
Abstract
Introduction Hemolytic-uremic syndrome (HUS) can occur as a systemic complication of infection with Shiga toxin (Stx)-producing Escherichia coli (STEC). Most well-known aspects of the pathophysiology are secondary to microthrombotic kidney disease including hemolytic anemia and thrombocytopenia. However, extrarenal manifestations, such as cardiac impairment, have also been reported. We have investigated whether these cardiac abnormalities can be reproduced in a murine animal model, in which administration of Stx, the main virulence factor of STEC, is used to induce HUS. Methods Mice received either one high or multiple low doses of Stx to simulate the (clinically well-known) different disease courses. Cardiac function was evaluated by echocardiography and analyses of biomarkers in the plasma (troponin I and brain natriuretic peptide). Results All Stx-challenged mice showed reduced cardiac output and depletion of intravascular volume indicated by a reduced end-diastolic volume and a higher hematocrit. Some mice exhibited myocardial injury (measured as increases in cTNI levels). A subset of mice challenged with either dosage regimen showed hyperkalemia with typical electrocardiographic abnormalities. Discussion Myocardial injury, intravascular volume depletion, reduced cardiac output, and arrhythmias as a consequence of hyperkalemia may be prognosis-relevant disease manifestations of HUS, the significance of which should be further investigated in future preclinical and clinical studies.
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Affiliation(s)
- Charles Neu
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Septomics Research Center, Jena University Hospital, Jena, Germany
- Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Bianka Wissuwa
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Septomics Research Center, Jena University Hospital, Jena, Germany
| | - Christoph Thiemermann
- William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Sina M. Coldewey
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Septomics Research Center, Jena University Hospital, Jena, Germany
- Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
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Zafar A, Lim MY, Abou-Ismail MY. Eculizumab in the management of drug-induced thrombotic microangiopathy: A scoping review of the literature. Thromb Res 2023; 224:73-79. [PMID: 36871347 DOI: 10.1016/j.thromres.2023.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/16/2023] [Accepted: 02/23/2023] [Indexed: 03/06/2023]
Abstract
Drug-induced TMA (DI-TMA) is a thrombotic microangiopathy (TMA) caused by certain drugs, usually managed by drug discontinuation and supportive measures. Data on the use of complement-inhibition with eculizumab in DI-TMA is scarce, and its benefit in cases of severe or refractory DI-TMA is unclear. We conducted a comprehensive search in PubMed, Embase and MEDLINE databases (2007-2021). We included articles that reported on DI-TMA patients treated with eculizumab and its clinical outcomes. All other causes of TMA were excluded. We evaluated the outcomes of hematologic recovery, renal recovery, and a composite of both (complete TMA recovery). 35 studies fulfilled our search criteria, which included 69 individual cases of DI-TMA treated with eculizumab. Most cases were secondary to chemotherapeutic agents, and the most implicated drugs were gemcitabine (42/69), carfilzomib (11/69), and bevacizumab (5/69). The median number of eculizumab doses given was 6 (range 1-16). 55/69 (80 %) patients achieved renal recovery, after 28-35 days (5-6 doses). 13/22 (59 %) patients were able to discontinue hemodialysis. 50/68 (74 %) patients achieved complete hematologic recovery after 7-14 days (1-2 doses). 41/68 (60 %) patients met criteria for complete TMA recovery. Eculizumab was safely tolerated in all cases, and appeared to be effective in achieving both hematologic and renal recovery in DI-TMA refractory to drug discontinuation and supportive measures, or with severe manifestations associated with significant morbidity or mortality. Our findings suggest that eculizumab may be considered as a potential treatment for severe or refractory DI-TMA that does not improve after initial management, although larger studies are needed.
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Affiliation(s)
- Aneeqa Zafar
- Division of Hematology, Bone Marrow Transplant and Cellular Therapy, Department of Internal Medicine, University of California, San Francisco, United States of America
| | - Ming Yeong Lim
- Division of Hematology and Hematologic Malignancies, Department of Internal Medicine, University of Utah Health Sciences Center, United States of America
| | - Mouhamed Yazan Abou-Ismail
- Division of Hematology and Hematologic Malignancies, Department of Internal Medicine, University of Utah Health Sciences Center, United States of America.
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Oral Administration with Live Attenuated Citrobacter rodentium Protects Immunocompromised Mice from Lethal Infection. Infect Immun 2022; 90:e0019822. [PMID: 35861565 PMCID: PMC9302154 DOI: 10.1128/iai.00198-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) are important causative agents for foodborne diseases worldwide. Besides antibiotic treatment, vaccination has been deemed as the most effective strategy for preventing EPEC- and EHEC-caused foodborne illnesses. Despite substantial progress made in identifying promising antigens and efficacious vaccines, no vaccines against EPEC or EHEC have yet been licensed. Mice are inherently resistant to EPEC and EHEC infections; infection with Citrobacter rodentium (CR), the murine equivalent of EPEC and EHEC, in mice has been widely used as a model to study bacterial pathogenesis and develop novel vaccine strategies. Mirroring the severe outcomes of EPEC and EHEC infections in immunocompromised populations, immunocompromised mouse strains such as interleukin-22 knockout (Il22-/-) are susceptible to CR infection with severe clinical symptoms and mortality. Live attenuated bacterial vaccine strategies have been scarcely investigated for EPEC and EHEC infections, in particular in immunocompromised populations associated with severe outcomes. Here we examined whether live attenuated CR strain with rational genetic manipulation generates protective immunity against lethal CR infection in the susceptible Il22-/- mice. Our results demonstrate that oral administration of live ΔespFΔushA strain promotes efficient systemic and humoral immunity against a wide range of CR virulence determinants, thus protecting otherwise lethal CR infection, even in immunocompromised Il22-/- mice. This provides a proof of concept of live attenuated vaccination strategy for preventing CR infection in immunocompromised hosts associated with more severe symptoms and lethality.
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8
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Enterohemorrhagic Escherichia coli and a Fresh View on Shiga Toxin-Binding Glycosphingolipids of Primary Human Kidney and Colon Epithelial Cells and Their Toxin Susceptibility. Int J Mol Sci 2022; 23:ijms23136884. [PMID: 35805890 PMCID: PMC9266556 DOI: 10.3390/ijms23136884] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/07/2022] [Accepted: 06/17/2022] [Indexed: 02/06/2023] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) are the human pathogenic subset of Shiga toxin (Stx)-producing E. coli (STEC). EHEC are responsible for severe colon infections associated with life-threatening extraintestinal complications such as the hemolytic-uremic syndrome (HUS) and neurological disturbances. Endothelial cells in various human organs are renowned targets of Stx, whereas the role of epithelial cells of colon and kidneys in the infection process has been and is still a matter of debate. This review shortly addresses the clinical impact of EHEC infections, novel aspects of vesicular package of Stx in the intestine and the blood stream as well as Stx-mediated extraintestinal complications and therapeutic options. Here follows a compilation of the Stx-binding glycosphingolipids (GSLs), globotriaosylceramide (Gb3Cer) and globotetraosylceramide (Gb4Cer) and their various lipoforms present in primary human kidney and colon epithelial cells and their distribution in lipid raft-analog membrane preparations. The last issues are the high and extremely low susceptibility of primary renal and colonic epithelial cells, respectively, suggesting a large resilience of the intestinal epithelium against the human-pathogenic Stx1a- and Stx2a-subtypes due to the low content of the high-affinity Stx-receptor Gb3Cer in colon epithelial cells. The review closes with a brief outlook on future challenges of Stx research.
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9
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Kudva IT, Trachsel J, Biernbaum EN, Casey T. Novel reusable animal model for comparative evaluation of in vivo growth and protein-expression of Escherichia coli O157 strains in the bovine rumen. PLoS One 2022; 17:e0268645. [PMID: 35617366 PMCID: PMC9135228 DOI: 10.1371/journal.pone.0268645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 05/04/2022] [Indexed: 11/18/2022] Open
Abstract
Previously, we had demonstrated that Escherichia coli O157:H7 (O157) strain 86–24 expresses proteins involved in survival rather than virulence in vitro in rumen fluid from dairy cattle limit fed a maintenance diet. Here, we verified if this observation would be true for different O157 strains grown in vitro in rumen fluid from, and in vivo in the rumen of, animals on contrasting maintenance (high fiber) and lactation (high energy-protein) diets usually limit fed to dairy cattle. For the in vivo studies, an economical, novel, reusable and non-terminal rumen-fistulated animal model permitting simultaneous evaluation of multiple bacterial strains in the bovine rumen was developed. All experiments were conducted in duplicate using different animals to account for host-related variations. The O157 strains included, 86–24, EDL933 and the super shed SS-17. E. coli NalR (#5735), derived from a bovine intestinal commensal E. coli, was included as a control. As expected, diet influenced ruminal pH and volatile fatty acid (VFA) composition. The pH ranged from 6.2–7.0 and total VFA concentrations from 109–141 μM/ml, in animals fed the maintenance diet. In comparison, animals fed the lactation diet had a ruminal pH ranging between 5.18–6.0, and total VFA of 125–219 μM/ml. Strain dependent differences in O157 recovery from the rumen fluid of cattle fed either diet was observed, both in vitro and in vivo, with O157 strains 86–24 and EDL933 demonstrating similar survival patterns. Analysis of the O157 proteomes expressed in the rumen fluid/rumen verified previous observations of adaptive responses. Any difference in the adaptive response was mainly influenced by the animal’s diet and growth conditions (in vitro and in vivo) and not the O157 strain. These new insights into the O157 responses could help formulate modalities to control O157 across strains in cattle at all stages of husbandry.
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Affiliation(s)
- Indira T. Kudva
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, Iowa
- * E-mail:
| | - Julian Trachsel
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, Iowa
| | - Erika N. Biernbaum
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, Iowa
- Oak Ridge Institute for Science and Education (ORISE), ARS Research Participation Program, Oak Ridge, Tennessee
| | - Thomas Casey
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, Iowa
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Abou‐Ismail MY, Kapoor S, Citla Sridhar D, Nayak L, Ahuja S. Thrombotic microangiopathies: An illustrated review. Res Pract Thromb Haemost 2022; 6:e12708. [PMID: 35615754 PMCID: PMC9027164 DOI: 10.1002/rth2.12708] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 03/09/2022] [Accepted: 03/13/2022] [Indexed: 11/11/2022] Open
Abstract
The thrombotic microangiopathies (TMAs) are a heterogenous group of disorders with distinct pathophysiologies that cause occlusive microvascular or macrovascular thrombosis, and are characterized by microangiopathic hemolytic anemia, thrombocytopenia, and/or end-organ ischemia. TMAs are associated with significant morbidity and mortality, and data on the management of certain TMAs are often lacking. The nomenclature, classification, and management of various TMAs is constantly evolving as we learn more about these rare syndromes. Thorough clinical and laboratory evaluation is essential to distinguish various TMAs and arrive at an accurate diagnosis, which is key for appropriate management. In this illustrated review, we focus on thrombotic thrombocytopenic purpura (TTP), Shiga toxin-associated hemolytic uremic syndrome, complement-mediated hemolytic uremic syndrome, hematopoietic cell transplant-associated TMA, and drug-induced TMA, and describe their incidence, pathophysiology, diagnosis, and management. We also highlight emerging complement-directed therapies under investigation for the management of complement-mediated TMAs.
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Affiliation(s)
- Mouhamed Yazan Abou‐Ismail
- Division of Hematology and Hematologic Malignancies Department of Internal Medicine University of Utah Health Sciences Center Salt Lake City Utah USA
| | - Sargam Kapoor
- Department of Hematology & Oncology Alaska Native Medical Center Anchorage Alaska USA
| | - Divyaswathi Citla Sridhar
- Department of Pediatric Hematology & Oncology University of Arkansas for Medical Sciences Little Rock Arkansas USA
| | - Lalitha Nayak
- Department of Hematology & Oncology University Hospitals Cleveland Medical Center Cleveland Ohio USA
| | - Sanjay Ahuja
- Department of Pediatric Hematology & Oncology University Hospitals Rainbow Babies and Children’s Hospital Cleveland Ohio USA
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Vo JL, Ortiz GCM, Totsika M, Lo AW, Hancock SJ, Whitten AE, Hor L, Peters KM, Ageorges V, Caccia N, Desvaux M, Schembri MA, Paxman JJ, Heras B. Variation of Antigen 43 self-association modulates bacterial compacting within aggregates and biofilms. NPJ Biofilms Microbiomes 2022; 8:20. [PMID: 35396507 PMCID: PMC8993888 DOI: 10.1038/s41522-022-00284-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 03/03/2022] [Indexed: 12/13/2022] Open
Abstract
The formation of aggregates and biofilms enhances bacterial colonisation and infection progression by affording protection from antibiotics and host immune factors. Despite these advantages there is a trade-off, whereby bacterial dissemination is reduced. As such, biofilm development needs to be controlled to suit adaptation to different environments. Here we investigate members from one of largest groups of bacterial adhesins, the autotransporters, for their critical role in the assembly of bacterial aggregates and biofilms. We describe the structural and functional characterisation of autotransporter Ag43 variants from different Escherichia coli pathotypes. We show that specific interactions between amino acids on the contacting interfaces of adjacent Ag43 proteins drives a common mode of trans-association that leads to cell clumping. Furthermore, subtle variation of these interactions alters aggregation kinetics and the degree of compacting within cell clusters. Together, our structure–function investigation reveals an underlying molecular basis for variations in the density of bacterial communities.
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Affiliation(s)
- Julieanne L Vo
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, 3086, Australia
| | - Gabriela C Martínez Ortiz
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, 3086, Australia
| | - Makrina Totsika
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Queensland University of Technology, Herston, QLD, 4006, Australia
| | - Alvin W Lo
- School of Chemistry and Molecular Biosciences, and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Steven J Hancock
- School of Chemistry and Molecular Biosciences, and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Andrew E Whitten
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, 2234, Australia
| | - Lilian Hor
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, 3086, Australia
| | - Kate M Peters
- School of Chemistry and Molecular Biosciences, and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Valentin Ageorges
- Université Clermont Auvergne, INRAE, UMR454 MEDiS, 63000, Clermont-Ferrand, France
| | - Nelly Caccia
- Université Clermont Auvergne, INRAE, UMR454 MEDiS, 63000, Clermont-Ferrand, France
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRAE, UMR454 MEDiS, 63000, Clermont-Ferrand, France
| | - Mark A Schembri
- School of Chemistry and Molecular Biosciences, and Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, 4072, Australia.
| | - Jason J Paxman
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, 3086, Australia.
| | - Begoña Heras
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, 3086, Australia.
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12
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Intestinal Enteroid Monolayers Model the Human Intestinal Environment for Escherichia coli Infection. J Bacteriol 2022; 204:e0062021. [PMID: 35389257 DOI: 10.1128/jb.00620-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterohemorrhagic Escherichia coli O157:H7 is an enteric pathogen responsible for bloody diarrhea, hemolytic uremic syndrome, and in severe cases, even death. The study of O157:H7 is difficult due to the high specificity of the bacteria for the human intestine, along with our lack of sufficiently complex human cell culture models. The recent development of human intestinal enteroids derived from intestinal crypt multipotent stem cells has allowed us to construct two-dimensional differentiated epithelial monolayers grown in transwells that mimic the human intestine. Unlike previous studies, saline was added to the apical surface, while maintaining culture media in the basolateral well. The monolayers continued to grow and differentiate with apical saline. Apical infection with O157:H7 or commensal E. coli resulted in robust bacterial growth from 105 to over 108 over 24 h. Despite this robust bacterial growth, commensal E. coli neither adhered to nor damaged the epithelial barrier over 30 h. However, O157:H7 was almost fully adhered (>90%) by 18 h with epithelial damage observed by 30 h. O157:H7 contains the locus of enterocyte effacement (LEE) pathogenicity island responsible for attachment and damage to the intestinal epithelium. Previous studies report the ability of nutrients such as biotin, d-serine, and L-fucose to downregulate LEE gene expression. O157:H7 treated with biotin or L-fucose, but not d-serine displayed both decreased attachment and reduced epithelial damage over 36 h. These data illustrate enteroid monolayers can serve as a suitable model for the study of O157:H7 pathogenesis, and identification of potential therapeutics. IMPORTANCE O157:H7 is difficult to study due to its high specificity for the human intestine and the lack of sufficiently complex human cell culture models. The recent development of human intestinal enteroids derived from intestinal crypt multipotent stem cells has allowed us to construct two-dimensional differentiated epithelial monolayers grown in transwells that mimic the human intestine. Our data illustrates enteroid monolayers can serve as a suitable model for the study of O157:H7 pathogenesis, and allow for identification of potential therapeutics.
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Formeck CL, Manrique-Caballero CL, Gómez H, Kellum JA. Uncommon Causes of Acute Kidney Injury. Crit Care Clin 2022; 38:317-347. [DOI: 10.1016/j.ccc.2021.11.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Divergent roles of haptoglobin and hemopexin deficiency for disease progression of Shiga-toxin-induced hemolytic-uremic syndrome in mice. Kidney Int 2022; 101:1171-1185. [PMID: 35031328 DOI: 10.1016/j.kint.2021.12.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 12/05/2021] [Accepted: 12/16/2021] [Indexed: 02/06/2023]
Abstract
Thrombotic microangiopathy, hemolysis and acute kidney injury are typical clinical characteristics of hemolytic-uremic syndrome (HUS), which is predominantly caused by Shiga-toxin-producing Escherichia coli. Free heme aggravates organ damage in life-threatening infections, even with a low degree of systemic hemolysis. Therefore, we hypothesized that the presence of the hemoglobin- and the heme-scavenging proteins, haptoglobin and hemopexin, respectively impacts outcome and kidney pathology in HUS. Here, we investigated the effect of haptoglobin and hemopexin deficiency (haptoglobin-/-, hemopexin-/-) and haptoglobin treatment in a murine model of HUS-like disease. Seven-day survival was decreased in haptoglobin-/- (25%) compared to wild type mice (71.4%), whereas all hemopexin-/- mice survived. Shiga-toxin-challenged hemopexin-/- mice showed decreased kidney inflammation and attenuated thrombotic microangiopathy, indicated by reduced neutrophil recruitment and platelet deposition. These observations were associated with supranormal haptoglobin plasma levels in hemopexin-/- mice. Low dose haptoglobin administration to Shiga-toxin-challenged wild type mice attenuated kidney platelet deposition and neutrophil recruitment, suggesting that haptoglobin at least partially contributes to the beneficial effects. Surrogate parameters of hemolysis were elevated in Shiga-toxin-challenged wild type and haptoglobin-/- mice, while signs for hepatic hemoglobin degradation like heme oxygenase-1, ferritin and CD163 expression were only increased in Shiga-toxin-challenged wild type mice. In line with this observation, haptoglobin-/- mice displayed tubular iron deposition as an indicator for kidney hemoglobin degradation. Thus, haptoglobin and hemopexin deficiency play divergent roles in Shiga-toxin-mediated HUS, suggesting haptoglobin is involved, and hemopexin is redundant for the resolution of HUS pathology.
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Costigan C, Raftery T, Carroll AG, Wildes D, Reynolds C, Cunney R, Dolan N, Drew RJ, Lynch BJ, O’Rourke DJ, Stack M, Sweeney C, Shahwan A, Twomey E, Waldron M, Riordan M, Awan A, Gorman KM. Neurological involvement in children with hemolytic uremic syndrome. Eur J Pediatr 2022; 181:501-512. [PMID: 34378062 PMCID: PMC8821508 DOI: 10.1007/s00431-021-04200-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 07/05/2021] [Accepted: 07/07/2021] [Indexed: 11/25/2022]
Abstract
Our objective was to establish the rate of neurological involvement in Shiga toxin-producing Escherichia coli-hemolytic uremic syndrome (STEC-HUS) and describe the clinical presentation, management and outcome. A retrospective chart review of children aged ≤ 16 years with STEC-HUS in Children's Health Ireland from 2005 to 2018 was conducted. Laboratory confirmation of STEC infection was required for inclusion. Neurological involvement was defined as encephalopathy, focal neurological deficit, and/or seizure activity. Data on clinical presentation, management, and outcome were collected. We identified 240 children with HUS; 202 had confirmed STEC infection. Neurological involvement occurred in 22 (11%). The most common presentation was seizures (73%). In the neurological group, 19 (86%) were treated with plasma exchange and/or eculizumab. Of the 21 surviving children with neurological involvement, 19 (91%) achieved a complete neurological recovery. A higher proportion of children in the neurological group had renal sequelae (27% vs. 12%, P = .031). One patient died from multi-organ failure.Conclusion: We have identified the rate of neurological involvement in a large cohort of children with STEC-HUS as 11%. Neurological involvement in STEC-HUS is associated with good long-term outcome (complete neurological recovery in 91%) and a low case-fatality rate (4.5%) in our cohort. What is Known: • HUS is associated with neurological involvement in up to 30% of cases. • Neurological involvement has been reported as predictor of poor outcome, with associated increased morbidity and mortality. What is New: • The incidence of neurological involvement in STEC-HUS is 11%. • Neurological involvement is associated with predominantly good long-term outcome (90%) and a reduced case-fatality rate (4.5%) compared to older reports.
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Affiliation(s)
- Caoimhe Costigan
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Tara Raftery
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Anne G. Carroll
- Department of Radiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
| | - Dermot Wildes
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Claire Reynolds
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Robert Cunney
- Department of Clinical Microbiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
- Irish Meningitis and Sepsis Reference Laboratory, Children’s Health Ireland At Temple Street, Dublin, Ireland
- Department of Clinical Microbiology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Niamh Dolan
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Richard J. Drew
- Department of Clinical Microbiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
- Irish Meningitis and Sepsis Reference Laboratory, Children’s Health Ireland At Temple Street, Dublin, Ireland
- Department of Clinical Microbiology, Royal College of Surgeons in Ireland, Dublin, Ireland
- Clinical Innovation Unit, Rotunda Hospital, Dublin, Ireland
| | - Bryan J. Lynch
- Department of Neurology and Clinical Neurophysiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
| | - Declan J. O’Rourke
- Department of Neurology and Clinical Neurophysiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Maria Stack
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Clodagh Sweeney
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Amre Shahwan
- Department of Neurology and Clinical Neurophysiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
- Department of Pediatrics, Royal College of Surgeons, Dublin, Ireland
| | - Eilish Twomey
- Department of Radiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
| | - Mary Waldron
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
| | - Michael Riordan
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
- Department of Pediatrics, Royal College of Surgeons, Dublin, Ireland
| | - Atif Awan
- Department of Nephrology, Children’s Health Ireland At Temple Street and Crumlin, Dublin, Ireland
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
- Department of Pediatrics, Royal College of Surgeons, Dublin, Ireland
| | - Kathleen M. Gorman
- Department of Neurology and Clinical Neurophysiology, Children’s Health Ireland At Temple Street, Dublin, Ireland
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
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Intestinal Organoids: New Tools to Comprehend the Virulence of Bacterial Foodborne Pathogens. Foods 2022; 11:foods11010108. [PMID: 35010234 PMCID: PMC8750402 DOI: 10.3390/foods11010108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/18/2021] [Accepted: 12/22/2021] [Indexed: 12/12/2022] Open
Abstract
Foodborne diseases cause high morbidity and mortality worldwide. Understanding the relationships between bacteria and epithelial cells throughout the infection process is essential to setting up preventive and therapeutic solutions. The extensive study of their pathophysiology has mostly been performed on transformed cell cultures that do not fully mirror the complex cell populations, the in vivo architectures, and the genetic profiles of native tissues. Following advances in primary cell culture techniques, organoids have been developed. Such technological breakthroughs have opened a new path in the study of microbial infectious diseases, and thus opened onto new strategies to control foodborne hazards. This review sheds new light on cellular messages from the host–foodborne pathogen crosstalk during in vitro organoid infection by the foodborne pathogenic bacteria with the highest health burden. Finally, future perspectives and current challenges are discussed to provide a better understanding of the potential applications of organoids in the investigation of foodborne infectious diseases.
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Antimicrobial Resistance, Serologic and Molecular Characterization of E. coli Isolated from Calves with Severe or Fatal Enteritis in Bavaria, Germany. Antibiotics (Basel) 2021; 11:antibiotics11010023. [PMID: 35052900 PMCID: PMC8772957 DOI: 10.3390/antibiotics11010023] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/17/2021] [Accepted: 12/24/2021] [Indexed: 11/17/2022] Open
Abstract
Worldwide, enterotoxigenic Escherichia coli (ETEC) cause neonatal diarrhea and high mortality rates in newborn calves, leading to great economic losses. In Bavaria, Germany, no recent facts are available regarding the prevalence of virulence factors or antimicrobial resistance of ETEC in calves. Antimicrobial susceptibility of 8713 E. coli isolates obtained from 7358 samples of diseased or deceased diarrheic calves were investigated between 2015 to 2019. Considerably high rates of 84.2% multidrug-resistant and 15.8% extensively drug-resistant isolates were detected. The resistance situation of the first, second and third line antimicrobials for the treatment, here amoxicillin-clavulanate, enrofloxacin and trimethoprim-sulfamethoxazole, is currently acceptable with mean non-susceptibility rates of 28.1%, 37.9% and 50.0% over the investigated 5-year period. Furthermore, the ETEC serotypes O101:K28, O9:K35, O101:K30, O101:K32, O78:K80, O139:K82, O8:K87, O141:K85 and O147:K89, as well as the virulence factors F17, F41, F5, ST-I and stx1 were identified in a subset of samples collected in 2019 and 2020. The substantially high rates of multi- and extensively drug-resistant isolates underline the necessity of continuous monitoring regarding antimicrobial resistance to provide reliable prognoses and adjust recommendations for the treatment of bacterial infections in animals.
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Ramstad SN, Brandal LT, Taxt AM, Wasteson Y, Bjørnholt JV, Naseer U. Prevalence of genotypic antimicrobial resistance in clinical Shiga toxin-producing Escherichia coli in Norway, 2018 to 2020. J Med Microbiol 2021; 70. [PMID: 34870582 PMCID: PMC8744279 DOI: 10.1099/jmm.0.001454] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Introduction Shiga toxin-producing Escherichia coli (STEC) can cause severe to fatal disease in humans. Antimicrobial treatment is sometimes necessary, but contraindicated due to undesirable clinical outcome. However, recent studies have shown promising outcomes following antimicrobial treatment. Before the establishment of a possible antimicrobial treatment strategy for STEC infections, the prevalence of antimicrobial resistance in STEC needs to be determined. Gap statement The resistance status of Norwegian clinical STEC is not known and should be assessed. Aim We aim to characterize genotypic antimicrobial resistance determinants in clinical STEC in Norway, and determine the prevalence of genotypic resistance in order to inform possible antimicrobial treatment options for STEC infections. Methodology We included all clinical STEC submitted to the Norwegian Reference Laboratory from March 2018 to April 2020. All samples were whole-genome sequenced and screened for genotypic antimicrobial resistance,virulence determinants and plasmid incompatibility groups. We performed phylogenetic clustering of STEC by core-genome multi-locus sequence typing, and statistical association analyses between isolate characteristics and genotypic resistance. Results A total of 459 STEC were analysed. For 385 (83.9 %) STEC we did not identify any antimicrobial resistance determinants. Seventy-four STEC (16.1 %) harboured antimicrobial resistance determinants against one or more antimicrobial classes. The most frequent genotypic resistance was identified against aminoglycosides (10.5 %). Thirty-nine STEC (8.5 %) had a multi-drug resistance (MDR) genotype. Genotypic resistance was more prevalent in non-O157 than O157 STEC (P=0.02). A positive association was seen between genotypic resistance and the low-virulent STEC O117:H7 phylogenetic cluster (no. 14) (P<0.001). Genotypic resistance was not significantly associated to high-virulent STEC. STEC O146:H28 and isolates harbouring the plasmid replicon type IncQ1 were positively associated with MDR. Conclusion The overall prevalence of genotypic resistance in clinical STEC in Norway is low (16.1 %). Genotypic resistance is more prevalent in non-O157 strains compared to O157 strains, and not significantly associated to high-virulent STEC. Resistance to antimicrobials suggested for treatment, especially azithromycin is low and may present an empiric treatment alternative for severe STEC infections.
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Affiliation(s)
- Silje N Ramstad
- Department of Microbiology, Division of Laboratory Medicine, Oslo University Hospital, PB 4956 Nydalen, 0424 Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Lin T Brandal
- Department of Infectious Diseases and Prevention, Norwegian Institute of Public Health, Oslo, Norway.,ECDC fellowship Programme, Public Health Microbiology path (EUPHEM), European Centre for Disease Prevention and Control (ECDC), Solna, Sweden
| | - Arne M Taxt
- Department of Microbiology, Division of Laboratory Medicine, Oslo University Hospital, PB 4956 Nydalen, 0424 Oslo, Norway.,Department of Infectious Diseases and Prevention, Norwegian Institute of Public Health, Oslo, Norway
| | - Yngvild Wasteson
- Department of Paraclinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Jørgen V Bjørnholt
- Department of Microbiology, Division of Laboratory Medicine, Oslo University Hospital, PB 4956 Nydalen, 0424 Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Umaer Naseer
- Department of Infectious Diseases and Prevention, Norwegian Institute of Public Health, Oslo, Norway
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Hotinger JA, Morris ST, May AE. The Case against Antibiotics and for Anti-Virulence Therapeutics. Microorganisms 2021; 9:2049. [PMID: 34683370 PMCID: PMC8537500 DOI: 10.3390/microorganisms9102049] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 12/14/2022] Open
Abstract
Although antibiotics have been indispensable in the advancement of modern medicine, there are downsides to their use. Growing resistance to broad-spectrum antibiotics is leading to an epidemic of infections untreatable by first-line therapies. Resistance is exacerbated by antibiotics used as growth factors in livestock, over-prescribing by doctors, and poor treatment adherence by patients. This generates populations of resistant bacteria that can then spread resistance genes horizontally to other bacterial species, including commensals. Furthermore, even when antibiotics are used appropriately, they harm commensal bacteria leading to increased secondary infection risk. Effective antibiotic treatment can induce bacterial survival tactics, such as toxin release and increasing resistance gene transfer. These problems highlight the need for new approaches to treating bacterial infection. Current solutions include combination therapies, narrow-spectrum therapeutics, and antibiotic stewardship programs. These mediate the issues but do not address their root cause. One emerging solution to these problems is anti-virulence treatment: preventing bacterial pathogenesis instead of using bactericidal agents. In this review, we discuss select examples of potential anti-virulence targets and strategies that could be developed into bacterial infection treatments: the bacterial type III secretion system, quorum sensing, and liposomes.
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Affiliation(s)
| | | | - Aaron E. May
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23219, USA; (J.A.H.); (S.T.M.)
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Blasco M, Guillén E, Quintana LF, Garcia-Herrera A, Piñeiro G, Poch E, Carreras E, Campistol JM, Diaz-Ricart M, Palomo M. Thrombotic microangiopathies assessment: mind the complement. Clin Kidney J 2021; 14:1055-1066. [PMID: 33841853 PMCID: PMC8023218 DOI: 10.1093/ckj/sfaa195] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 08/31/2020] [Indexed: 12/11/2022] Open
Abstract
When faced with microangiopathic haemolytic anaemia, thrombocytopenia and organ dysfunction, clinicians should suspect thrombotic microangiopathy (TMA). The endothelial damage that leads to this histological lesion can be triggered by several conditions or diseases, hindering an early diagnosis and aetiological treatment. However, due to systemic involvement in TMA and its low incidence, an accurate early diagnosis is often troublesome. In the last few decades, major improvements have been made in the pathophysiological knowledge of TMAs such as thrombotic thrombocytopenic purpura [TTP, caused by ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin Type 1 motif, member 13) deficiency] and atypical haemolytic uraemic syndrome (aHUS, associated with dysregulation of the alternative complement pathway), together with enhancements in patient management due to new diagnostic tools and treatments. However, diagnosis of aHUS requires the exclusion of all the other entities that can cause TMA, delaying the introduction of terminal complement blockers, which have shown high efficacy in haemolysis control and especially in avoiding organ damage if used early. Importantly, there is increasing evidence that other forms of TMA could present overactivation of the complement system, worsening their clinical progression. This review addresses the diagnostic and therapeutic approach when there is clinical suspicion of TMA, emphasizing complement evaluation as a potential tool for the inclusive diagnosis of aHUS, as well as for the improvement of current knowledge of its pathophysiological involvement in other TMAs. The development of both new complement activation biomarkers and inhibitory treatments will probably improve the management of TMA patients in the near future, reducing response times and improving patient outcomes.
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Affiliation(s)
- Miquel Blasco
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Centro de Referencia en Enfermedad Glomerular Compleja del Sistema Nacional de Salud (CSUR), University of Barcelona, Barcelona, Spain
- Institute of Biomedical Research August Pi i Sunyer (IDIPABS), Malalties Nefro-Urològiques i Trasplantament Renal, Barcelona, Spain
| | - Elena Guillén
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Centro de Referencia en Enfermedad Glomerular Compleja del Sistema Nacional de Salud (CSUR), University of Barcelona, Barcelona, Spain
| | - Luis F Quintana
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Centro de Referencia en Enfermedad Glomerular Compleja del Sistema Nacional de Salud (CSUR), University of Barcelona, Barcelona, Spain
- Institute of Biomedical Research August Pi i Sunyer (IDIPABS), Malalties Nefro-Urològiques i Trasplantament Renal, Barcelona, Spain
| | | | - Gastón Piñeiro
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Centro de Referencia en Enfermedad Glomerular Compleja del Sistema Nacional de Salud (CSUR), University of Barcelona, Barcelona, Spain
- Institute of Biomedical Research August Pi i Sunyer (IDIPABS), Malalties Nefro-Urològiques i Trasplantament Renal, Barcelona, Spain
| | - Esteban Poch
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Centro de Referencia en Enfermedad Glomerular Compleja del Sistema Nacional de Salud (CSUR), University of Barcelona, Barcelona, Spain
- Institute of Biomedical Research August Pi i Sunyer (IDIPABS), Malalties Nefro-Urològiques i Trasplantament Renal, Barcelona, Spain
| | - Enric Carreras
- Josep Carreras Leukaemia Research Institute, Hospital Clinic/University of Barcelona Campus, Barcelona, Spain
- Barcelona Endothelium Team, Barcelona, Spain
| | - Josep M Campistol
- Department of Nephrology and Kidney Transplantation, Hospital Clínic, Centro de Referencia en Enfermedad Glomerular Compleja del Sistema Nacional de Salud (CSUR), University of Barcelona, Barcelona, Spain
- Institute of Biomedical Research August Pi i Sunyer (IDIPABS), Malalties Nefro-Urològiques i Trasplantament Renal, Barcelona, Spain
| | - Maribel Diaz-Ricart
- Barcelona Endothelium Team, Barcelona, Spain
- Department of Pathology, Hematopathology Unit, Hospital Clínic of Barcelona, Biomedical Diagnosis Centre (CDB), Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | - Marta Palomo
- Josep Carreras Leukaemia Research Institute, Hospital Clinic/University of Barcelona Campus, Barcelona, Spain
- Barcelona Endothelium Team, Barcelona, Spain
- Department of Pathology, Hematopathology Unit, Hospital Clínic of Barcelona, Biomedical Diagnosis Centre (CDB), Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
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Evaluation of Cattle for Naturally Colonized Shiga Toxin-Producing Escherichia coli Requires Combinatorial Strategies. Int J Microbiol 2021; 2021:6673202. [PMID: 33868404 PMCID: PMC8032530 DOI: 10.1155/2021/6673202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/06/2021] [Accepted: 03/21/2021] [Indexed: 01/01/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) serogroups O157, O26, O103, O111, O121, O145, and O45 are designated as food adulterants by the U.S. Department of Agriculture-Food Safety and Inspection Service. Cattle are the primary reservoir of these human pathogens. In this study, 59 Angus crossbred heifers were tested specifically for these seven STEC serogroups using a combination of standard culture, serological, PCR, and cell cytotoxicity methods to determine if comparable results would be obtained. At the time of fecal sampling, the animals were approximately 2 years old and weighed 1000–1200 lbs. The diet comprised of 37% ground alfalfa hay, 25% ground Sudan hay, and 38% ground corn supplemented with trace minerals and rumensin with ad libitum access to water. Non-O157 STEC were isolated from 25% (15/59) of the animals tested using a combination of EC broth, CHROMagar STECTM, and Rainbow Agar O157. Interestingly, the O157 serogroup was not isolated from any of the animals. Non-O157 STEC isolates were confirmed to be one of the six adulterant serogroups by serology and/or colony PCR in 10/15 animals with the predominant viable, serogroup being O103. PCR using DNA extracted from feces verified most of the colony PCR results but also identified additional virulence and O-antigen genes from samples with no correlating culture results. Shiga toxin- (Stx-) related cytopathic effects on Vero cells with fecal extracts from 55/59 animals could only be associated with the Stx gene profiles obtained by fecal DNA PCR and not culture results. The differences between culture versus fecal DNA PCR and cytotoxicity assay results suggest that the latter two assays reflect the presence of nonviable STEC or infection with STEC not belonging to the seven adulterant serogroups. This study further supports the use of combinatorial culture, serology, and PCR methods to isolate viable STEC that pose a greater food safety threat.
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Warr AR, Kuehl CJ, Waldor MK. Shiga toxin remodels the intestinal epithelial transcriptional response to Enterohemorrhagic Escherichia coli. PLoS Pathog 2021; 17:e1009290. [PMID: 33529199 PMCID: PMC7880444 DOI: 10.1371/journal.ppat.1009290] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 02/12/2021] [Accepted: 01/07/2021] [Indexed: 12/22/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) is a food-borne pathogen that causes diarrheal disease and the potentially lethal hemolytic uremic syndrome. We used an infant rabbit model of EHEC infection that recapitulates many aspects of human intestinal disease to comprehensively assess colonic transcriptional responses to this pathogen. Cellular compartment-specific RNA-sequencing of intestinal tissue from animals infected with EHEC strains containing or lacking Shiga toxins (Stx) revealed that EHEC infection elicits a robust response that is dramatically shaped by Stx, particularly in epithelial cells. Many of the differences in the transcriptional responses elicited by these strains were in genes involved in immune signaling pathways, such as IL23A, and coagulation, including F3, the gene encoding Tissue Factor. RNA FISH confirmed that these elevated transcripts were found almost exclusively in epithelial cells. Collectively, these findings suggest that Stx potently remodels the host innate immune response to EHEC. Enterohemorrhagic Escherichia coli (EHEC) is a potentially lethal foodborne pathogen. During infection, EHEC releases a potent toxin, Shiga toxin (Stx), into the intestine, but there is limited knowledge of how this toxin shapes the host response to infection. We used an infant rabbit model of infection that closely mimics human disease to profile intestinal transcriptomic responses to EHEC infection. Comparisons of the transcriptional responses to infection by strains containing or lacking Stx revealed that this toxin markedly remodels how the epithelial cell compartment responds to infection. Our findings suggest that Stx shapes the intestinal innate immune response to EHEC and provide insight into the complex host-pathogen dialogue that underlies disease.
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Affiliation(s)
- Alyson R. Warr
- Division of Infectious Diseases, Brigham & Women’s Hospital, Boston, Massachusetts, United States of America
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Carole J. Kuehl
- Division of Infectious Diseases, Brigham & Women’s Hospital, Boston, Massachusetts, United States of America
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Matthew K. Waldor
- Division of Infectious Diseases, Brigham & Women’s Hospital, Boston, Massachusetts, United States of America
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America
- Howard Hughes Medical Institute, Boston, Massachusetts, United States of America
- * E-mail:
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Pian YY, Nie JJ, Wang CC, Liu Q, Liu Z, Zhang LQ, Ou-Yang QG, Fan GQ, Zeng LT, Dang YM, Ma YQ, Zhang W, Gao ZX, Hu JH, Cai JP. Systemic RNA oxidation can be used as a biomarker of infection in challenged with Vibrio parahaemolyticus. Free Radic Res 2021; 55:41-52. [PMID: 33470868 DOI: 10.1080/10715762.2020.1857376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
More and more evidence support the concept that RNA oxidation plays a substantial role in the progress of multiple diseases; however, only a few studies have reported RNA oxidation caused by microbial pathogens. Urinary 8-oxo-7,8-dihydroguanosine (8-oxo-Gsn) and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGsn), which are broadly used as indicators of oxidative damage of RNA and DNA, were analyzed in this study to determine which can be used as a biomarker of infection in challenged with Vibrio parahaemolyticus (V. parahaemolyticus). In this work, 24 specific-pathogen-free (SPF) male SD rats were randomly divided into two groups: an infection group and a phosphate-buffered saline (PBS) control group. Our results proved that 8-oxo-Gsn rather than 8-oxo-dGsn was significantly increased after challenged with V. parahaemolyticus in urine and tissue samples of SD rats compared with the PBS control group. Simultaneously, white blood cells (WBCs) counts, intestinal inflammation and inflammatory factors (including CRP, IL-6, IL-1β, TNF-α, IL-10, and IL-17A) were also increased sharply. Which has more clinical value is that the trend of urinary 8-oxo-Gsn was consistent with WBCs, intestinal inflammation and all kinds of inflammatory factors. More importantly is that urinary 8-oxo-Gsn of infection group was positively correlated with WBCs and various inflammatory cytokines. In a word, our results demonstrated that as a systemic RNA oxidation biomarker, we hope 8-oxo-Gsn can be used as a biomarker of the severity of microbial pathogens infection, rather than a specific biomarker of microbial pathogens infection.
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Affiliation(s)
- Ya-Ya Pian
- National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Jing-Jing Nie
- National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Chen-Chen Wang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China.,Department of Pharmacy, Wenzhou Medical University, Wenzhou, China
| | - Qian Liu
- Department of Pharmacy, Wenzhou Medical University, Wenzhou, China
| | - Zhen Liu
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Li-Qun Zhang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Qiu-Geng Ou-Yang
- Department of Pharmacy, Wenzhou Medical University, Wenzhou, China
| | - Guo-Qing Fan
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Lv-Tao Zeng
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Ya-Min Dang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Ya-Qing Ma
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei Zhang
- Department of Pathology, National Center of Gerontology, Beijing Hospital, Beijing, China
| | - Zhen-Xiang Gao
- National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Ji-Hong Hu
- National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Jian-Ping Cai
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, National Health Commission, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
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Ramstad SN, Taxt AM, Naseer U, Wasteson Y, Bjørnholt JV, Brandal LT. Effects of antimicrobials on Shiga toxin production in high-virulent Shiga toxin-producing Escherichia coli. Microb Pathog 2020; 152:104636. [PMID: 33242644 DOI: 10.1016/j.micpath.2020.104636] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 11/10/2020] [Accepted: 11/16/2020] [Indexed: 12/16/2022]
Abstract
PURPOSE Antimicrobial treatment of Shiga toxin-producing Escherichia coli (STEC) infections is controversial because antimicrobials may stimulate Shiga toxin (Stx) production, and thereby increase the risk of developing haemolytic uremic syndrome (HUS). Previous in vitro studies have shown this mainly in infections caused by STEC serotype O157:H7. The aim of this study was to investigate induction of Stx transcription and production in different serotypes of STEC isolated from severely ill patients, following their exposure in vitro to six different classes of antimicrobials. METHODS We investigated Stx transcription and production in 12 high-virulent STEC strains, all carrying the stx2a gene, of six different serotypes following their exposure to six classes of antimicrobials. Liquid cultures of the STEC strains were incubated with sub-inhibitory concentrations of the antimicrobials. We used reverse-transcription quantitative PCR to measure the relative expression of Stx2a mRNA and an enzyme-linked immunosorbent assay to quantify Stx production. RESULTS In general the antibiotics tested showed only minor effects on transcriptional levels of Stx2a. Ciprofloxacin caused an increase of Stx production in all but two strains, while gentamicin, meropenem and azithromycin did not induce Stx production in any of the STEC strains examined. STEC O104:H4 was the serotype that in greatest extent responded to antimicrobial exposure with an increase of stx2a transcription and Stx production. CONCLUSION Gentamicin, meropenem and azithromycin exposure did not result in elevated Stx production. We recommend that this finding is investigated further in the search for candidates for future antimicrobial treatment of STEC.
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Affiliation(s)
- Silje N Ramstad
- Department of Microbiology, Division of Laboratory Medicine, Oslo University Hospital, PB 4956 Nydalen, 0424, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
| | - Arne M Taxt
- Department of Microbiology, Division of Laboratory Medicine, Oslo University Hospital, PB 4956 Nydalen, 0424, Oslo, Norway
| | - Umaer Naseer
- Department of Infectious Diseases and Prevention, Norwegian Institute of Public Health, Oslo, Norway
| | - Yngvild Wasteson
- Department of Paraclinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Jørgen V Bjørnholt
- Department of Microbiology, Division of Laboratory Medicine, Oslo University Hospital, PB 4956 Nydalen, 0424, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Lin T Brandal
- Department of Infectious Diseases and Prevention, Norwegian Institute of Public Health, Oslo, Norway
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25
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Quintela IA, Wu VCH. A sandwich-type bacteriophage-based amperometric biosensor for the detection of Shiga toxin-producing Escherichia coli serogroups in complex matrices. RSC Adv 2020; 10:35765-35775. [PMID: 35517084 PMCID: PMC9056931 DOI: 10.1039/d0ra06223e] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/15/2020] [Indexed: 12/19/2022] Open
Abstract
Immuno-based biosensors are a popular tool designed for pathogen screening and detection. The current antibody-based biosensors employ direct, indirect, or sandwich detection approaches; however, instability, cross-reactivity, and high-cost render them unreliable and impractical. To circumvent these drawbacks, here we report a portable sandwich-type bacteriophage-based amperometric biosensor, which is highly-specific to various Shiga toxin-producing Escherichia coli (STEC) serogroups. Environmentally isolated and biotinylated bacteriophages were directly immobilized onto a streptavidin-coated screen-printed carbon electrode (SPCE), which recognized and captured viable target cells. Samples (50 μL) were transferred to these bacteriophage-functionalized SPCEs (12 min, room temp) before sequentially adding a bacteriophage–gold nanoparticle solution (20 μL), H2O2 (40 mM), and 1,1′-ferrocenedicarboxylic acid for amperometric tests (100 mV s−1) and analysis (ANOVA and LSD, P < 0.05). The optimum biotin concentration (10 mM) retained 94.47% bacteriophage viability. Non-target bacteria (Listeria monocytogenes and Salmonella Typhimurium) had delta currents below the threshold of a positive detection. With less than 1 h turn-around time, the amperometric biosensor had a detection limit of 10–102 CFU mL−1 for STEC O157, O26, and O179 strains and R2 values of 0.97, 0.99, and 0.87, respectively, and a similar detection limit was observed in complex matrices, 10–102 CFU g−1 or mL−1 with R2 values of 0.98, 0.95, and 0.76, respectively. The newly developed portable amperometric biosensor was able to rapidly detect viable target cells at low inoculum levels, thus providing an inexpensive and improved alternative to the current immuno- and laboratory-based STEC screening methods. Sandwich-type bacteriophage-based amperometric biosensor for the detection of Shiga toxin-producing Escherichia coli serogroups in complex matrices.![]()
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Affiliation(s)
- Irwin A Quintela
- Produce Safety and Microbiology Research Unit, US Department of Agriculture, Agricultural Research Services, Western Regional Research Center Albany California USA
| | - Vivian C H Wu
- Produce Safety and Microbiology Research Unit, US Department of Agriculture, Agricultural Research Services, Western Regional Research Center Albany California USA
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26
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Menge C. The Role of Escherichia coli Shiga Toxins in STEC Colonization of Cattle. Toxins (Basel) 2020; 12:toxins12090607. [PMID: 32967277 PMCID: PMC7551371 DOI: 10.3390/toxins12090607] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 11/20/2022] Open
Abstract
Many cattle are persistently colonized with Shiga toxin-producing Escherichia coli (STEC) and represent a major source of human infections with human-pathogenic STEC strains (syn. enterohemorrhagic E. coli (EHEC)). Intervention strategies most effectively protecting humans best aim at the limitation of bovine STEC shedding. Mechanisms enabling STEC to persist in cattle are only partialy understood. Cattle were long believed to resist the detrimental effects of Shiga toxins (Stxs), potent cytotoxins acting as principal virulence factors in the pathogenesis of human EHEC-associated diseases. However, work by different groups, summarized in this review, has provided substantial evidence that different types of target cells for Stxs exist in cattle. Peripheral and intestinal lymphocytes express the Stx receptor globotriaosylceramide (Gb3syn. CD77) in vitro and in vivo in an activation-dependent fashion with Stx-binding isoforms expressed predominantly at early stages of the activation process. Subpopulations of colonic epithelial cells and macrophage-like cells, residing in the bovine mucosa in proximity to STEC colonies, are also targeted by Stxs. STEC-inoculated calves are depressed in mounting appropriate cellular immune responses which can be overcome by vaccination of the animals against Stxs early in life before encountering STEC. Considering Stx target cells and the resulting effects of Stxs in cattle, which significantly differ from effects implicated in human disease, may open promising opportunities to improve existing yet insufficient measures to limit STEC carriage and shedding by the principal reservoir host.
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Affiliation(s)
- Christian Menge
- Friedrich-Loeffler-Institut/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, D-07743 Jena, Germany
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27
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Vavougios GD, Nday C, Pelidou SH, Zarogiannis SG, Gourgoulianis KI, Stamoulis G, Doskas T. Double hit viral parasitism, polymicrobial CNS residency and perturbed proteostasis in Alzheimer's disease: A data driven, in silico analysis of gene expression data. Mol Immunol 2020; 127:124-135. [PMID: 32971399 DOI: 10.1016/j.molimm.2020.08.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 07/25/2020] [Accepted: 08/30/2020] [Indexed: 01/04/2023]
Abstract
The aim of this study was to determine the interaction of peripheral immunity vs. the CNS in the setting of AD pathogenesis at the transcriptomic level in a data driven manner. For this purpose, publicly available gene expression data from the GEO Datasets repository. We performed differential gene expression and functional enrichment analyses were performed on the five retrieved studies: (a) three hippocampal cortex (HC) studies (b) one study of peripheral blood mononuclear cells (PBMC) and (c) one involving neurofibrillary tangle - containing neurons of the entorhinal cortex (NFT EC). Subsequently, BLAST was used to determine protein conservation between human proteins vs. microbial, whereas putative protein / oligopeptide antigenicity were determined via RANKPep. Gene ontology and pathway analyses revealed significantly enriched viral parasitism pathways in both PBMC and NFT - EC datasets, mediated by ribosomal protein families and epigenetic regulators. Among these, a salient viral pathway referred to Influenza A infection. NFT - EC annotations included leukocyte chemotaxis and immune response pathways. All datasets were significantly enriched for infectious pathways, as well as pathways involved in impaired proteostasis and non - phagocytic cell phagosomal cascades. In conclusion, our in silico analysis outlined an ad hoc model of AD pathophysiology in which double hit (PBMC and NFT-EC) viral parasitism is mediated by eukaryotic translational hijacking, and may be further implicated by impaired immune responses. Overall, our results overlap with the antimicrobial protection hypothesis of AD pathogenesis and support the notion of a pathogen - driven etiology.
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Affiliation(s)
- George D Vavougios
- Department of Neurology, Athens Naval Hospital, P.C. 115 21, Athens, Greece; Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, Biopolis, P.C, 41500, Larissa, Greece; Department of Computer Science and Telecommunications, University of Thessaly, Papasiopoulou 2 - 4, P.C. 35 131 Galaneika, Lamia, Greece.
| | - Christiane Nday
- Laboratory of Medical Physics, Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, P.C. 5414, Thessaloniki, Greece
| | | | - Sotirios G Zarogiannis
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Thessaly, BIOPOLIS, Larissa, 41500, Greece
| | - Konstantinos I Gourgoulianis
- Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, Biopolis, P.C, 41500, Larissa, Greece
| | - George Stamoulis
- Department of Electrical and Computer Engineering, University of Thessaly, 37 Glavani - 28th October Str, Deligiorgi Building, 4th floor, P.C. 382 21, Volos, Greece
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28
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Singh P, Cubillos G, Kirshteyn G, Bosilevac JM. High-resolution melting real-time PCR assays for detection of Escherichia coli O26 and O111 strains possessing Shiga toxin genes. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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29
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Valid Presumption of Shiga Toxin-Mediated Damage of Developing Erythrocytes in EHEC-Associated Hemolytic Uremic Syndrome. Toxins (Basel) 2020; 12:toxins12060373. [PMID: 32512916 PMCID: PMC7354503 DOI: 10.3390/toxins12060373] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 02/06/2023] Open
Abstract
The global emergence of clinical diseases caused by enterohemorrhagic Escherichia coli (EHEC) is an issue of great concern. EHEC release Shiga toxins (Stxs) as their key virulence factors, and investigations on the cell-damaging mechanisms toward target cells are inevitable for the development of novel mitigation strategies. Stx-mediated hemolytic uremic syndrome (HUS), characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal injury, is the most severe outcome of an EHEC infection. Hemolytic anemia during HUS is defined as the loss of erythrocytes by mechanical disruption when passing through narrowed microvessels. The formation of thrombi in the microvasculature is considered an indirect effect of Stx-mediated injury mainly of the renal microvascular endothelial cells, resulting in obstructions of vessels. In this review, we summarize and discuss recent data providing evidence that HUS-associated hemolytic anemia may arise not only from intravascular rupture of erythrocytes, but also from the extravascular impairment of erythropoiesis, the development of red blood cells in the bone marrow, via direct Stx-mediated damage of maturing erythrocytes, leading to “non-hemolytic” anemia.
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30
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Molecular Biology of Escherichia Coli Shiga Toxins' Effects on Mammalian Cells. Toxins (Basel) 2020; 12:toxins12050345. [PMID: 32456125 PMCID: PMC7290813 DOI: 10.3390/toxins12050345] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 12/11/2022] Open
Abstract
Shiga toxins (Stxs), syn. Vero(cyto)toxins, are potent bacterial exotoxins and the principal virulence factor of enterohemorrhagic Escherichia coli (EHEC), a subset of Shiga toxin-producing E. coli (STEC). EHEC strains, e.g., strains of serovars O157:H7 and O104:H4, may cause individual cases as well as large outbreaks of life-threatening diseases in humans. Stxs primarily exert a ribotoxic activity in the eukaryotic target cells of the mammalian host resulting in rapid protein synthesis inhibition and cell death. Damage of endothelial cells in the kidneys and the central nervous system by Stxs is central in the pathogenesis of hemolytic uremic syndrome (HUS) in humans and edema disease in pigs. Probably even more important, the toxins also are capable of modulating a plethora of essential cellular functions, which eventually disturb intercellular communication. The review aims at providing a comprehensive overview of the current knowledge of the time course and the consecutive steps of Stx/cell interactions at the molecular level. Intervention measures deduced from an in-depth understanding of this molecular interplay may foster our basic understanding of cellular biology and microbial pathogenesis and pave the way to the creation of host-directed active compounds to mitigate the pathological conditions of STEC infections in the mammalian body.
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31
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Development and Evaluation of a Novel VHH-Based Immunocapture Assay for High-Sensitivity Detection of Shiga Toxin Type 2 (Stx2) in Stool Samples. J Clin Microbiol 2020; 58:JCM.01566-19. [PMID: 31826960 DOI: 10.1128/jcm.01566-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/04/2019] [Indexed: 12/16/2022] Open
Abstract
Shiga toxin (Stx)-producing Escherichia coli (STEC) is the main cause of postdiarrheal hemolytic-uremic syndrome (HUS), a life-threatening clinical complication characterized by hemolytic anemia, thrombocytopenia, and acute renal failure that mainly affects children. A relevant feature of STEC strains is the production of Stx, and all of them express Stx1 and/or Stx2 regardless of the strain serotype. Therefore, Stx detection assays are considered the most suitable methods for the early detection of STEC infections. Single-domain antibodies from camelids (VHHs) exhibit several advantages in comparison with conventional antibodies, making them promising tools for diagnosis. In this work, we have exploited VHH technology for the development of an immunocapture assay for Stx2 detection. Thirteen anti-Stx2 VHHs previously obtained from a variable-domain repertoire library were selected and evaluated in 130 capture-detection pair combinations for Stx detection. Based on this analysis, two VHHs were selected and a double VHH-based biotin-streptavidin capture enzyme-linked immunosorbent assay (ELISA) with spectrophotometric detection was developed and optimized for Stx2 detection. This assay showed an excellent analytical and clinical sensitivity in both STEC culture supernatants and stool samples even higher than the sensitivity of a commercial ELISA. Furthermore, based on the analysis of stool samples, the VHH-based ELISA showed high correlation with stx 2 detection by PCR and a commercial rapid membrane-based immunoassay. The intrinsic properties of VHHs (high target affinity and specificity, stability, and ease of expression at high yields in recombinant bacteria) and their optimal performance for Stx detection make them attractive tools for the diagnosis of HUS related to STEC (STEC-HUS).
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32
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Jarocki VM, Reid CJ, Chapman TA, Djordjevic SP. Escherichia coli ST302: Genomic Analysis of Virulence Potential and Antimicrobial Resistance Mediated by Mobile Genetic Elements. Front Microbiol 2020; 10:3098. [PMID: 32063891 PMCID: PMC6985150 DOI: 10.3389/fmicb.2019.03098] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 12/20/2019] [Indexed: 12/31/2022] Open
Abstract
aEPEC are associated with persistent diarrhea, and diarrheal outbreaks in both humans and animals worldwide. They are differentiated from typical EPEC by the lack of bundle-forming pili, and from EHEC by the lack of phage-mediated stx toxins. However, phylogenetic analyses often associate aEPEC with EHEC, promoting the hypothesis that aEPEC are the progenitors of EHEC, which is supported by aEPEC conversion to EHEC by stx-carrying phages. While aEPEC can cause disease outright, the potential to acquire stx, one of the most potent bacterial toxins known, merits close monitoring. Escherichia coli ST302 (O108:H9, O182:H9, O45:H9) are aEPEC that have been isolated from diarrheic human, pig and rabbit hosts, as well as in healthy pigs, however, no study to date has focused on E. coli ST302 strains. Through WGS and hybrid assembly we present the first closed chromosome, and two circularized plasmids of an ST302 strain - F2_18C, isolated from a healthy pig in Australia. A phylogenetic analysis placed E. coli ST302 strains in proximity to EHEC ST32 (O145:H28) strains. Public databases were interrogated for WGSs of E. coli ST302 strains and short-read gene screens were used to compare their virulence-associated gene (VAG) and antimicrobial resistance gene (ARG) cargo. E. coli ST302 strains carry diverse VAGs, including those that typically associated with extraintestinal pathogenic E. coli (ExPEC). Plasmid comparisons showed that pF2_18C_FIB shared homology with EHEC virulence plasmids such as pO103 while pF2_18C_HI2 is a large multidrug resistance IncHI2:ST3 plasmid. A comparison of 33 HI2:ST3 plasmids demonstrated that those of Australian origin have not acquired resistances to extended-spectrum beta-lactams, colistin, fosfomycin or rifampicin, unlike those originating from Asia. F2_18C was shown to carry two additional pathogenicity islands – ETT2, and the STEC-associated PAICL3, plasmid-associated heavy metal resistance genes, as well as several unoccupied stx-phage attachment sites. This study sheds light on the virulence and AMR potential of E. coli ST302 strains and informs AMR genomic surveillance.
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Affiliation(s)
- Veronica M Jarocki
- ithree institute, University of Technology Sydney, Sydney, NSW, Australia.,Australian Centre for Genomic Epidemiological Microbiology, University of Technology Sydney, Sydney, NSW, Australia
| | - Cameron J Reid
- ithree institute, University of Technology Sydney, Sydney, NSW, Australia.,Australian Centre for Genomic Epidemiological Microbiology, University of Technology Sydney, Sydney, NSW, Australia
| | - Toni A Chapman
- NSW Department of Primary Industries, Elizabeth MacArthur Agricultural Institute, Menangle, NSW, Australia
| | - Steven P Djordjevic
- ithree institute, University of Technology Sydney, Sydney, NSW, Australia.,Australian Centre for Genomic Epidemiological Microbiology, University of Technology Sydney, Sydney, NSW, Australia
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33
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Joseph A, Cointe A, Mariani Kurkdjian P, Rafat C, Hertig A. Shiga Toxin-Associated Hemolytic Uremic Syndrome: A Narrative Review. Toxins (Basel) 2020; 12:E67. [PMID: 31973203 PMCID: PMC7076748 DOI: 10.3390/toxins12020067] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 01/13/2020] [Accepted: 01/17/2020] [Indexed: 01/28/2023] Open
Abstract
The severity of human infection by one of the many Shiga toxin-producing Escherichia coli (STEC) is determined by a number of factors: the bacterial genome, the capacity of human societies to prevent foodborne epidemics, the medical condition of infected patients (in particular their hydration status, often compromised by severe diarrhea), and by our capacity to devise new therapeutic approaches, most specifically to combat the bacterial virulence factors, as opposed to our current strategies that essentially aim to palliate organ deficiencies. The last major outbreak in 2011 in Germany, which killed more than 50 people in Europe, was evidence that an effective treatment was still lacking. Herein, we review the current knowledge of STEC virulence, how societies organize the prevention of human disease, and how physicians treat (and, hopefully, will treat) its potentially fatal complications. In particular, we focus on STEC-induced hemolytic and uremic syndrome (HUS), where the intrusion of toxins inside endothelial cells results in massive cell death, activation of the coagulation within capillaries, and eventually organ failure.
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Affiliation(s)
- Adrien Joseph
- Department of Nephrology, AP-HP, Hôpital Tenon, F-75020 Paris, France; (A.J.); (C.R.)
| | - Aurélie Cointe
- Department of Microbiology, AP-HP, Hôpital Robert Debré, F-75019 Paris, France; (A.C.); (P.M.K.)
| | | | - Cédric Rafat
- Department of Nephrology, AP-HP, Hôpital Tenon, F-75020 Paris, France; (A.J.); (C.R.)
| | - Alexandre Hertig
- Department of Renal Transplantation, Sorbonne Université, AP-HP, Hôpital Pitié Salpêtrière, F-75013 Paris, France
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34
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Siddiqui R, Nadeem S, Menon N, Nesiama JA. Ultrasound Evidence of Acute Appendicitis in a Patient with Hemolytic Uremic Syndrome. JOURNAL OF EMERGENCY MEDICINE CASE REPORTS 2020. [DOI: 10.33706/jemcr.543056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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35
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Deshmukh F, Agrawal U, Merrell N. Clostridioides difficile co-infection with Enterohemorrhagic Escherichia coli (EHEC)—a potentially fatal combination. IDCases 2020; 21:e00797. [PMID: 32489867 PMCID: PMC7256656 DOI: 10.1016/j.idcr.2020.e00797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/03/2020] [Accepted: 05/03/2020] [Indexed: 10/25/2022] Open
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36
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Genomic Comparison Reveals Natural Occurrence of Clinically Relevant Multidrug-Resistant Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains. Appl Environ Microbiol 2019; 85:AEM.03030-18. [PMID: 31053578 DOI: 10.1128/aem.03030-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/24/2019] [Indexed: 02/06/2023] Open
Abstract
The effectiveness of antibiotics has been challenged by the increasing frequency of antimicrobial resistance (AMR), which has emerged as a major threat to global health. Despite its negative impact on the development of AMR, there are few effective strategies for reducing AMR in food-producing animals. Using whole-genome sequencing and comparative genomics of 36 multidrug-resistant (MDR) Escherichia coli strains isolated from beef cattle with no previous exposure to antibiotics, we obtained results suggesting that the occurrence of MDR E. coli also arises in animals with no antibiotic selective pressure. Extended-spectrum-β-lactamase-producing E. coli strains with enhanced virulence capacities for toxin production and adherence have evolved, which implies important ramifications for animal and human health. Gene exchanges by conjugative plasmids and insertion elements have driven widespread antibiotic resistance in clinically relevant pathogens. Phylogenetic relatedness of E. coli strains from various geographic locations and hosts, such as animals, environmental sources, and humans, suggests that transmission of MDR E. coli strains occurs intercontinentally without host barriers.IMPORTANCE Multidrug-resistant (MDR) Escherichia coli isolates pose global threats to public health due to the decreasing availability of treatment options. To better understand the characteristics of MDR E. coli isolated from food-producing animals with no antibiotic exposure, we employed genomic comparison, high-resolution phylogenetics, and functional characterization. Our findings highlight the potential capacity of MDR E. coli to cause severe disease and suggest that these strains are widespread intercontinentally. This study underlines the occurrence of MDR E. coli in food-producing animals raised without antibiotic use, which has alarming, critical ramifications within animal and human medical practice.
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Oh CK, Moon Y. Dietary and Sentinel Factors Leading to Hemochromatosis. Nutrients 2019; 11:nu11051047. [PMID: 31083351 PMCID: PMC6566178 DOI: 10.3390/nu11051047] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/29/2019] [Accepted: 05/07/2019] [Indexed: 02/06/2023] Open
Abstract
Although hereditary hemochromatosis is associated with the mutation of genes involved in iron transport and metabolism, secondary hemochromatosis is due to external factors, such as intended or unintended iron overload, hemolysis-linked iron exposure or other stress-impaired iron metabolism. The present review addresses diet-linked etiologies of hemochromatosis and their pathogenesis in the network of genes and nutrients. Although the mechanistic association to diet-linked etiologies can be complicated, the stress sentinels are pivotally involved in the pathological processes of secondary hemochromatosis in response to iron excess and other external stresses. Moreover, the mutations in these sentineling pathway-linked genes increase susceptibility to secondary hemochromatosis. Thus, the crosstalk between nutrients and genes would verify the complex procedures in the clinical outcomes of secondary hemochromatosis and chronic complications, such as malignancy. All of this evidence provides crucial insights into comprehensive clinical or nutritional interventions for hemochromatosis.
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Affiliation(s)
- Chang-Kyu Oh
- Laboratory of Mucosal Exposome and Biomodulation, Department of Biomedical Sciences, Pusan National University, Yangsan 50612, Korea.
| | - Yuseok Moon
- Laboratory of Mucosal Exposome and Biomodulation, Department of Biomedical Sciences, Pusan National University, Yangsan 50612, Korea.
- BioMedical Research Institute, Pusan National University, Yangsan 50612, Korea.
- Program of Food Health Sciences, Busan 46241, Korea.
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Bernabeu M, Sánchez-Herrero JF, Huedo P, Prieto A, Hüttener M, Rozas J, Juárez A. Gene duplications in the E. coli genome: common themes among pathotypes. BMC Genomics 2019; 20:313. [PMID: 31014240 PMCID: PMC6480617 DOI: 10.1186/s12864-019-5683-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 04/10/2019] [Indexed: 11/12/2022] Open
Abstract
Background Gene duplication underlies a significant proportion of gene functional diversity and genome complexity in both eukaryotes and prokaryotes. Although several reports in the literature described the duplication of specific genes in E. coli, a detailed analysis of the extent of gene duplications in this microorganism is needed. Results The genomes of the E. coli enteroaggregative strain 042 and other pathogenic strains contain duplications of the gene that codes for the global regulator Hha. To determine whether the presence of additional copies of the hha gene correlates with the presence of other genes, we performed a comparative genomic analysis between E. coli strains with and without hha duplications. The results showed that strains harboring additional copies of the hha gene also encode the yeeR irmA (aec69) gene cluster, which, in turn, is also duplicated in strain 042 and several other strains. The identification of these duplications prompted us to obtain a global map of gene duplications, first in strain 042 and later in other E. coli genomes. Duplications in the genomes of the enteroaggregative strain 042, the uropathogenic strain CFT073 and the enterohemorrhagic strain O145:H28 have been identified by a BLASTp protein similarity search. This algorithm was also used to evaluate the distribution of the identified duplicates among the genomes of a set of 28 representative E. coli strains. Despite the high genomic diversity of E. coli strains, we identified several duplicates in the genomes of almost all studied pathogenic strains. Most duplicated genes have no known function. Transcriptomic analysis also showed that most of these duplications are regulated by the H-NS/Hha proteins. Conclusions Several duplicated genes are widely distributed among pathogenic E. coli strains. In addition, some duplicated genes are present only in specific pathotypes, and others are strain specific. This gene duplication analysis shows novel relationships between E. coli pathotypes and suggests that newly identified genes that are duplicated in a high percentage of pathogenic E. coli isolates may play a role in virulence. Our study also shows a relationship between the duplication of genes encoding regulators and genes encoding their targets. Electronic supplementary material The online version of this article (10.1186/s12864-019-5683-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Manuel Bernabeu
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Spain
| | - José Francisco Sánchez-Herrero
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Spain.,Biodiversity Research Institute (IRBio), University of Barcelona, Barcelona, Spain
| | - Pol Huedo
- Institute of Biotechnology and Biomedicine (IBB), Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Alejandro Prieto
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Spain
| | - Mário Hüttener
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Spain
| | - Julio Rozas
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Spain.,Biodiversity Research Institute (IRBio), University of Barcelona, Barcelona, Spain
| | - Antonio Juárez
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Spain. .,Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain.
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Abstract
Outer membrane vesicles (OMVs) are nanosized proteoliposomes derived from the outer membrane of Gram-negative bacteria. They are ubiquitously produced both in culture and during infection and are now recognized to play crucial roles during host-microbe interactions. OMVs can transport a broad range of chemically diverse cargoes, including lipids and lipopolysaccharides, membrane-embedded and associated proteins and small molecules, peptidoglycan, and nucleic acids. Particularly, virulence factors such as adhesins and toxins are often enriched in OMVs. Here we discuss a variety of ways in which OMVs facilitate host-microbe interactions, including their contributions to biofilm formation, nutrient scavenging, and modulation of host cell function. We particularly examine recent findings regarding OMV-host cell interactions in the oral cavity and the gastrointestinal tract.
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Alegbeleye OO, Oyebisi Afolabi WA, Opeolu BO, Khaneghah AM. Impacts of Vending Practices on the Microbiological Quality of Bread in the Ojoo Area of Ibadan, Oyo-State, Nigeria. CURRENT NUTRITION & FOOD SCIENCE 2019. [DOI: 10.2174/1573401313666171016162832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background: Bacterial counts in ready-to-eat foods are a key factor in assessing the microbiological quality and safety of food. Periodic assessment of the microbiological quality of food is necessary to develop a robust database and help to ensure food safety. </P><P> Methods: The bacterial contamination of a total of 336 bread samples collected from two bakeries and 10 vendors in Ojoo Area of Ibadan, Oyo-State, Nigeria (December 2014 -June 2015) was evaluated. The microbiological quality of the bread loaves was investigated using standard microbiological methods (morphological, phenotypic and molecular characterization). </P><P> Results: The results showed that the number of contaminated samples among the vended bread samples was higher than the bakery bread samples and can be summarized as Bacillus megaterium (4.30%), Staphylococcus arlettae (0.005%), Staphylococcus saprophyticus (2.78%), Citrobacter freundii (2.40%), Bacillus flexus (1.64%), Bacillus species (49.59%), Pseudomonas aeruginosa (4.12%), Pseudomonas fluorescens (0.92%), Pseudomonas species (0.045%), Escherichia coli (30.44%) Klebsiella sp. (0.040%) and Aeromonas hydrophila (3.72%). </P><P> Conclusion: The findings demonstrate that the bread samples which become contaminated after transport and handling can be considered a potential hazard to human health in the area. More stringent adherence to food safety regulations should be encouraged and enforced by the appropriate authorities. The findings of this study may be adopted to improve the hygienic conditions of bread distribution chain in the area as well as in other regions of the World.
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Affiliation(s)
| | - Wasiu Akinloye Oyebisi Afolabi
- Department of Nutrition and Dietetics, College of Food Science and Human Ecology, Federal University of Agriculture, Abeokuta, Nigeria
| | - Beatrice Oluwatoyin Opeolu
- Extended Curriculum Programmes, Faculty of Applied Sciences, Cape Peninsula University of Technology, Cape Town, South Africa
| | - Amin Mousavi Khaneghah
- Department of Food Science, Faculty of Food Engineering, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
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42
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An impedimetric biosensor for E. coli O157:H7 based on the use of self-assembled gold nanoparticles and protein G. Mikrochim Acta 2019; 186:169. [DOI: 10.1007/s00604-019-3282-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 01/23/2019] [Indexed: 10/27/2022]
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43
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The Evasive Enemy: Insights into the Virulence and Epidemiology of the Emerging Attaching and Effacing Pathogen Escherichia albertii. Infect Immun 2018; 87:IAI.00254-18. [PMID: 30373891 DOI: 10.1128/iai.00254-18] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 10/18/2018] [Indexed: 01/10/2023] Open
Abstract
The diarrheic attaching and effacing (A/E) pathogen Escherichia albertii was first isolated from infants in Bangladesh in 1991, although the bacterium was initially classified as Hafnia alvei Subsequent genetic and biochemical interrogation of these isolates raised concerns about their initial taxonomic placement. It was not until 2003 that these isolates were reassigned to the novel taxon Escherichia albertii because they were genetically more closely related to E. coli, although they had diverged sufficiently to warrant a novel species name. Unfortunately, new isolates continue to be mistyped as enteropathogenic E. coli (EPEC) or enterohemorrhagic E. coli (EHEC) owing to shared traits, most notably the ability to form A/E lesions. Consequently, E. albertii remains an underappreciated A/E pathogen, despite multiple reports demonstrating that many provisional EPEC and EHEC isolates incriminated in disease outbreaks are actually E. albertii Metagenomic studies on dozens of E. albertii isolates reveal a genetic architecture that boasts an arsenal of candidate virulence factors to rival that of its better-characterized cousins, EPEC and EHEC. Beyond these computational comparisons, studies addressing the regulation, structure, function, and mechanism of action of its repertoire of virulence factors are lacking. Thus, the paucity of knowledge about the epidemiology, virulence, and antibiotic resistance of E. albertii, coupled with its misclassification and its ability to develop multidrug resistance in a single step, highlights the challenges in combating this emerging pathogen. This review seeks to synthesize our current but incomplete understanding of the biology of E. albertii.
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Dextran Sulfate Sodium Colitis Facilitates Colonization with Shiga Toxin-Producing Escherichia coli: a Novel Murine Model for the Study of Shiga Toxicosis. Infect Immun 2018; 86:IAI.00530-18. [PMID: 30150257 DOI: 10.1128/iai.00530-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 08/23/2018] [Indexed: 12/23/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) bacteria are globally important gastrointestinal pathogens causing hemorrhagic gastroenteritis with variable progression to potentially fatal Shiga toxicosis. Little is known about the potential effects of E. coli-derived Shiga-like toxins (STXs) on host gastrointestinal immune responses during infection, in part due to the lack of a reproducible immunocompetent-animal model of STEC infection without depleting the commensal microbiota. Here, we describe a novel and reproducible murine model utilizing dextran sulfate sodium (DSS) colitis to induce susceptibility to colonization with clinical-isolate STEC strains. After exposure to DSS and subsequent oral STEC challenge, all the mice were colonized, and 66% of STEC-infected mice required early euthanasia. Morbidity during STEC infection, but not infection with an isogenic STEC mutant with toxin deleted, was associated with increased renal transcripts of the injury markers KIM1 and NGAL, histological evidence of renal tubular injury, and increased renal interleukin 6 gene (IL-6) and CXCL1 inflammatory transcripts. Interestingly, the intestinal burden of STEC during infection was increased compared to its isogenic Shiga toxin deletion strain. Increased bacterial burdens during Shiga toxin production coincided with decreased induction of colonic IL-23 axis transcripts known to be critical for clearance of similar gastrointestinal pathogens in mice, suggesting a previously undescribed role for STEC Shiga toxins in suppressing host immune responses during STEC infection and survival. The DSS+STEC model establishes infection with clinical-isolate strains of STEC in immunocompetent mice without depleting the gastrointestinal microbiota, enabling characterization of the effects of STXs on the IL-23 axis and other gastrointestinal pathogen-host interactions.
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45
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Wang X, Li X, Sun Z. iTRAQ-based quantitative proteomic analysis of the earthworm Eisenia fetida response to Escherichia coli O157:H7. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 160:60-66. [PMID: 29793202 DOI: 10.1016/j.ecoenv.2018.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 04/30/2018] [Accepted: 05/03/2018] [Indexed: 06/08/2023]
Abstract
Soil environment contaminated by Escherichia coli O157:H7 which come from the waste of infected animals. Earthworms can live in the pathogens-polluted soil by their innate immunity. How the proteins of earthworms E. fetida will response to E. coli O157:H7-contaminated-soil still unclear? To identify the defense proteins under E. coli O157:H7 stress, we performed a proteomic analysis of earthworm under E. coli O157:H7 exposure through an iTRAQ technology. In total, we found 283 non-redundant proteins, including fibrinolytic protease 1, lombricine kinase, lysozyme, gelsolin, coelomic cytolytic factor-1, antimicrobial peptide lumbricin-l, lysenin, and et al. The proteins participate in metabolic processes, transcription, defense response to bacterium, translation, response to stress, and transport. The study will contribute to understand why earthworm can live in the pathogens-polluted environment.
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Affiliation(s)
- Xing Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China.
| | - Xiaoqin Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Zhenjun Sun
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
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46
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Brigotti M, Arfilli V, Carnicelli D, Ricci F, Tazzari PL, Ardissino G, Scavia G, Morabito S, He X. Soluble Toll-Like Receptor 4 Impairs the Interaction of Shiga Toxin 2a with Human Serum Amyloid P Component. Toxins (Basel) 2018; 10:toxins10090379. [PMID: 30231570 PMCID: PMC6162853 DOI: 10.3390/toxins10090379] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 09/07/2018] [Accepted: 09/14/2018] [Indexed: 11/16/2022] Open
Abstract
Shiga toxin 2a (Stx2a) is the main virulence factor produced by pathogenic Escherichia coli strains (Stx-producing E. coli, STEC) responsible for hemorrhagic colitis and the life-threatening sequela hemolytic uremic syndrome in children. The toxin released in the intestine by STEC targets the globotriaosylceramide receptor (Gb3Cer) present on the endothelial cells of the brain and the kidney after a transient blood phase during which Stx2a interacts with blood components, such as neutrophils, which, conversely, recognize Stx through Toll-like receptor 4 (TLR4). Among non-cellular blood constituents, human amyloid P component (HuSAP) is considered a negative modulating factor that specifically binds Stx2a and impairs its toxic action. Here, we show that the soluble extracellular domain of TLR4 inhibits the binding of Stx2a to neutrophils, assessed by indirect flow cytometric analysis. Moreover, by using human sensitive Gb3Cer-expressing cells (Raji cells) we found that the complex Stx2a/soluble TLR4 escaped from capture by HuSAP allowing the toxin to target and damage human cells, as assayed by measuring translation inhibition, the typical Stx-induced functional impairment. Thus, soluble TLR4 stood out as a positive modulating factor for Stx2a. In the paper, these findings have been discussed in the context of the pathogenesis of hemolytic uremic syndrome.
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Affiliation(s)
- Maurizio Brigotti
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Via San Giacomo 14, 40126 Bologna, Italy.
| | - Valentina Arfilli
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Via San Giacomo 14, 40126 Bologna, Italy.
| | - Domenica Carnicelli
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Via San Giacomo 14, 40126 Bologna, Italy.
| | - Francesca Ricci
- Immunohematology and Transfusion Center, S. Orsola-Malpighi Hospital, Via Massarenti 9, 40138 Bologna, Italy.
| | - Pier Luigi Tazzari
- Immunohematology and Transfusion Center, S. Orsola-Malpighi Hospital, Via Massarenti 9, 40138 Bologna, Italy.
| | - Gianluigi Ardissino
- Center for HUS Control, Prevention and Management, Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico, Via Commenda 9, 20122 Milano, Italy.
| | - Gaia Scavia
- European Reference Laboratory for Escherichia coli, Istituto Superiore di Sanità, 00161 Rome, Italy.
| | - Stefano Morabito
- European Reference Laboratory for Escherichia coli, Istituto Superiore di Sanità, 00161 Rome, Italy.
| | - Xiaohua He
- Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, CA 94710, USA.
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Dennhardt S, Pirschel W, Wissuwa B, Daniel C, Gunzer F, Lindig S, Medyukhina A, Kiehntopf M, Rudolph WW, Zipfel PF, Gunzer M, Figge MT, Amann K, Coldewey SM. Modeling Hemolytic-Uremic Syndrome: In-Depth Characterization of Distinct Murine Models Reflecting Different Features of Human Disease. Front Immunol 2018; 9:1459. [PMID: 29988557 PMCID: PMC6026657 DOI: 10.3389/fimmu.2018.01459] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 06/12/2018] [Indexed: 12/25/2022] Open
Abstract
Diarrhea-positive hemolytic-uremic syndrome (HUS) is a renal disorder that results from infections with Shiga-toxin (Stx)-producing Escherichia coli. The aim of this study was to establish well-defined refined murine models of HUS that can serve as preclinical tools to elucidate molecular mechanisms of disease development. C57BL/6J mice were subjected to different doses of Stx2 purified from an E. coli O157:H7 patient isolate. Animals received 300 ng/kg Stx2 and were sacrificed on day 3 to establish an acute model with fast disease progression. Alternatively, mice received 25 ng/kg Stx2 on days 0, 3, and 6, and were sacrificed on day 7 to establish a subacute model with moderate disease progression. Indicated by a rise in hematocrit, we observed dehydration despite volume substitution in both models, which was less pronounced in mice that underwent the 7-day regime. Compared with sham-treated animals, mice subjected to Stx2 developed profound weight loss, kidney dysfunction (elevation of plasma urea, creatinine, and neutrophil gelatinase-associated lipocalin), kidney injury (tubular injury and loss of endothelial cells), thrombotic microangiopathy (arteriolar microthrombi), and hemolysis (elevation of plasma bilirubin, lactate dehydrogenase, and free hemoglobin). The degree of complement activation (C3c deposition), immune cell invasion (macrophages and T lymphocytes), apoptosis, and proliferation were significantly increased in kidneys of mice subjected to the 7-day but not in kidneys of mice subjected to the 3-day regime. However, glomerular and kidney volume remained mainly unchanged, as assessed by 3D analysis of whole mount kidneys using CD31 staining with light sheet fluorescence microscopy. Gene expression analysis of kidneys revealed a total of only 91 overlapping genes altered in both Stx2 models. In conclusion, we have developed two refined mouse models with different disease progression, both leading to hemolysis, thrombotic microangiopathy, and acute kidney dysfunction and damage as key clinical features of human HUS. While intrarenal changes (apoptosis, proliferation, complement deposition, and immune cell invasion) mainly contribute to the pathophysiology of the subacute model, prerenal pathomechanisms (hypovolemia) play a predominant role in the acute model. Both models allow the further study of the pathomechanisms of most aspects of human HUS and the testing of distinct novel treatment strategies.
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Affiliation(s)
- Sophie Dennhardt
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany.,Septomics Research Center, Jena University Hospital, Jena, Germany.,Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Wiebke Pirschel
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany.,Septomics Research Center, Jena University Hospital, Jena, Germany
| | - Bianka Wissuwa
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany.,Septomics Research Center, Jena University Hospital, Jena, Germany
| | - Christoph Daniel
- Department of Nephropathology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Florian Gunzer
- Institute of Medical Microbiology and Hygiene/Institute of Virology, TU Dresden, Dresden, Germany
| | - Sandro Lindig
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
| | - Anna Medyukhina
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Leibniz-Association, Jena, Germany
| | - Michael Kiehntopf
- Department of Clinical Chemistry and Laboratory Medicine, Jena University Hospital, Jena, Germany
| | - Wolfram W Rudolph
- Institute of Medical Microbiology and Hygiene/Institute of Virology, TU Dresden, Dresden, Germany
| | - Peter F Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Matthias Gunzer
- Institute for Experimental Immunology and Imaging, University Hospital, University Duisburg-Essen, Essen, Germany
| | - Marc Thilo Figge
- Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany.,Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Leibniz-Association, Jena, Germany.,Friedrich Schiller University (FSU) Jena, Jena, Germany
| | - Kerstin Amann
- Department of Nephropathology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Sina M Coldewey
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany.,Septomics Research Center, Jena University Hospital, Jena, Germany.,Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
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Citrobacter rodentium alters the mouse colonic miRNome. Genes Immun 2018; 20:207-213. [PMID: 29728609 DOI: 10.1038/s41435-018-0026-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 02/11/2018] [Accepted: 02/22/2018] [Indexed: 12/12/2022]
Abstract
Citrobacter rodentium is a murine pathogen causing transmissible colonic hyperplasia and colitis with a pathogenic mechanism similar to foodborne enterohaemorrhagic Escherichia coli in humans. Mechanisms underlying intestinal responses to C. rodentium infection are incompletely understood. We identified 24 colonic microRNAs (miRNAs) as significantly deregulated in response to C. rodentium, including miR-7a, -17, -19a, -20a, -20b, -92a, -106a, -132, -200a, and -2137; most of these miRNAs belong to the oncogenic miR-17-92 clusters. Pathways involved in cell cycle, cancers, and immune responses were enriched among the predicted targets of these miRNAs. We further demonstrated that an apoptosis facilitator, Bim, is a candidate gene target of miRNA-mediated host response to the infection. These findings suggest that host miRNAs participate in C. rodentium pathogenesis and may represent novel treatment targets.
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Hüttener M, Prieto A, Espelt J, Bernabeu M, Juárez A. Stringent Response and AggR-Dependent Virulence Regulation in the Enteroaggregative Escherichia coli Strain 042. Front Microbiol 2018; 9:717. [PMID: 29692772 PMCID: PMC5902536 DOI: 10.3389/fmicb.2018.00717] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 03/27/2018] [Indexed: 12/22/2022] Open
Abstract
Virulence expression in the enteroaggregative Escherichia coli strain 042 requires the transcriptional activator AggR. We show in this report that, as reported for other virulence factors, the nucleotide second messenger (p)ppGpp is needed for a high expression level of AggR. As expected from these findings, expression of AggR-activated genes such as the AafA pilin subunit is downregulated in the absence of (p)ppGpp. Considering the fact that biofilm formation in strain 042 requires the AafA protein, biofilm development in strain 042 is impaired in derivatives that lack either the AggR protein, the virulence plasmid that encodes AggR (pAA2) or the ability to synthesize (p)ppGpp. These results show a direct correlation between (p)ppGpp, expression of AggR and biofilm development in strain 042.
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Affiliation(s)
- Mário Hüttener
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Alejandro Prieto
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Joan Espelt
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Manuel Bernabeu
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Antonio Juárez
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Barcelona, Spain.,Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain
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50
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Kuo CJ, Wang ST, Chen CS. Detection of Enterohemorrhagic Escherichia Coli Colonization in Murine Host by Non-invasive In Vivo Bioluminescence System. J Vis Exp 2018. [PMID: 29683443 DOI: 10.3791/56169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Enterohemorrhagic E. coli (EHEC) O157:H7, which is a foodborne pathogen that causesdiarrhea, hemorrhagic colitis (HS), and hemolytic uremic syndrome (HUS), colonize to the intestinal tract of humans. To study the detailed mechanism of EHEC colonization in vivo, it is essential to have animal models to monitor and quantify EHEC colonization. We demonstrate here a mouse-EHEC colonization model by transforming the bioluminescent expressing plasmid to EHEC to monitor and quantify EHEC colonization in living hosts. Animals inoculated with bioluminescence-labeled EHEC show intense bioluminescent signals in mice by detection with a non-invasive in vivo imaging system. After 1 and 2 days post infection, bioluminescent signals could still be detected in infected animals, which suggests that EHEC colonize in hosts for at least 2 days. We also demonstrate that these bioluminescent EHEC locate to mouse intestine, specifically in the cecum and colon, from ex vivo images. This mouse-EHEC colonization model may serve as a tool to advance the current knowledge of the EHEC colonization mechanism.
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Affiliation(s)
- Cheng-Ju Kuo
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University; Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University
| | - Sin-Tian Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University; Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University
| | - Chang-Shi Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University; Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University;
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