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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: 3] [Impact Index Per Article: 1.5] [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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2
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Detzner J, Püttmann C, Pohlentz G, Humpf HU, Mellmann A, Karch H, Müthing J. Primary Human Colon Epithelial Cells (pHCoEpiCs) Do Express the Shiga Toxin (Stx) Receptor Glycosphingolipids Gb3Cer and Gb4Cer and Are Largely Refractory but Not Resistant towards Stx. Int J Mol Sci 2021; 22:ijms221810002. [PMID: 34576167 PMCID: PMC8472147 DOI: 10.3390/ijms221810002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 01/13/2023] Open
Abstract
Shiga toxin (Stx) is released by enterohemorrhagic Escherichia coli (EHEC) into the human intestinal lumen and transferred across the colon epithelium to the circulation. Stx-mediated damage of human kidney and brain endothelial cells and renal epithelial cells is a renowned feature, while the sensitivity of the human colon epithelium towards Stx and the decoration with the Stx receptor glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer, Galα1-4Galβ1-4Glcβ1-1Cer) and globotetraosylceramide (Gb4Cer, GalNAcβ1-3Galα1-4Galβ1-4Glcβ1-1Cer) is a matter of debate. Structural analysis of the globo-series GSLs of serum-free cultivated primary human colon epithelial cells (pHCoEpiCs) revealed Gb4Cer as the major neutral GSL with Cer (d18:1, C16:0), Cer (d18:1, C22:1/C22:0) and Cer (d18:1, C24:2/C24:1) accompanied by minor Gb3Cer with Cer (d18:1, C16:0) and Cer (d18:1, C24:1) as the dominant lipoforms. Gb3Cer and Gb4Cer co-distributed with cholesterol and sphingomyelin to detergent-resistant membranes (DRMs) used as microdomain analogs. Exposure to increasing Stx concentrations indicated only a slight cell-damaging effect at the highest toxin concentration of 1 µg/mL for Stx1a and Stx2a, whereas a significant effect was detected for Stx2e. Considerable Stx refractiveness of pHCoEpiCs that correlated with the rather low cellular content of the high-affinity Stx-receptor Gb3Cer renders the human colon epithelium questionable as a major target of Stx1a and Stx2a.
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Affiliation(s)
- Johanna Detzner
- Institute for Hygiene, University of Münster, 48149 Münster, Germany; (J.D.); (C.P.); (G.P.); (A.M.); (H.K.)
| | - Charlotte Püttmann
- Institute for Hygiene, University of Münster, 48149 Münster, Germany; (J.D.); (C.P.); (G.P.); (A.M.); (H.K.)
| | - Gottfried Pohlentz
- Institute for Hygiene, University of Münster, 48149 Münster, Germany; (J.D.); (C.P.); (G.P.); (A.M.); (H.K.)
| | - Hans-Ulrich Humpf
- Institute for Food Chemistry, University of Münster, 48149 Münster, Germany;
| | - Alexander Mellmann
- Institute for Hygiene, University of Münster, 48149 Münster, Germany; (J.D.); (C.P.); (G.P.); (A.M.); (H.K.)
| | - Helge Karch
- Institute for Hygiene, University of Münster, 48149 Münster, Germany; (J.D.); (C.P.); (G.P.); (A.M.); (H.K.)
| | - Johannes Müthing
- Institute for Hygiene, University of Münster, 48149 Münster, Germany; (J.D.); (C.P.); (G.P.); (A.M.); (H.K.)
- Correspondence: ; Tel.: +49-(0)251-8355192
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3
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Bease AG, Cassady-Cain RL, Stevens MP. Interaction of Bovine Lymphocytes with Products of Shiga Toxin-Producing Escherichia coli. Methods Mol Biol 2021; 2291:333-352. [PMID: 33704762 DOI: 10.1007/978-1-0716-1339-9_16] [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] [Indexed: 06/12/2023]
Abstract
Shiga toxin-producing Escherichia coli (STEC) produce a number of virulence factors that interfere with lymphocyte functions, including mitogen- and antigen-activated proliferation and pro-inflammatory cytokine synthesis. Here we describe how to isolate lymphocyte subsets from bovine peripheral blood as well as methods that we have used to study the effects of STEC products on lymphocyte proliferation and cytokine production. We also describe an assay that allows for the detection of association of a given protein with lymphocytes.
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Affiliation(s)
- Andrew G Bease
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK.
| | - Robin L Cassady-Cain
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK
| | - Mark P Stevens
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK
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4
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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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Pro-inflammatory capacity of Escherichia coli O104:H4 outbreak strain during colonization of intestinal epithelial cells from human and cattle. Int J Med Microbiol 2018; 308:899-911. [PMID: 29937390 DOI: 10.1016/j.ijmm.2018.06.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 06/16/2018] [Indexed: 10/28/2022] Open
Abstract
In 2011, Germany was struck by the largest outbreak of hemolytic uremic syndrome. The highly virulent E. coli O104:H4 outbreak strain LB226692 possesses a blended virulence profile combining genetic patterns of human adapted enteroaggregative E. coli (EAEC), rarely detected in animal hosts before, and enterohemorrhagic E. coli (EHEC), a subpopulation of Shiga toxin (Stx)-producing E. coli (STEC) basically adapted to the ruminant host. This study aimed at appraising the relative level of adaptation of the EAEC/EHEC hybrid strain LB226692 to humans and cattle. Adherence and invasion of the hybrid strain to intestinal (jejunal and colonic) epithelial cells (IEC) of human and bovine origin was compared to that of E. coli strains representative of different pathovars and commensal E. coli by means of light and electron microscopy and culture. Strain-specific host gene transcription profiles of selected cytokines and chemokines as well as host-induced transcription of bacterial virulence genes were assessed. The release of Stx upon host cell contact was quantified. The outbreak strain's immunomodulation was assessed by cultivating primary bovine macrophages with conditioned supernatants from IEC infection studies with E. coli, serving as model for the innate immunity of the bovine gut. The outbreak strain adhered to IEC of both, human and bovine origin. Electron microscopy of infected cells revealed the strain's particular affinity to human small IEC, in contrast to few interactions with bovine small IEC. The outbreak strain possessed a high-level of adhesive power, similar to human-associated E. coli strains and in contrast to bovine-associated STEC strains. The outbreak strain displayed a non-invasive phenotype, in contrast to some bovine-associated E. coli strains, which were invasive. The outbreak strain provoked some pro-inflammatory activity in human cells, but to a lower extent as compared to other pathotypes. In contrasts to bovine-associated E. coli strains, the outbreak strain induced marked pro-inflammatory activity when interacting with bovine host cells directly (IEC) and indirectly (macrophages). Among stx2-positive strains, the human-pathogenic strains (LB226692 and EHEC strain 86-24) released higher amounts of Stx compared to bovine-associated STEC. The findings imply that the outbreak strain is rather adapted to humans than to cattle. However, the outbreak strain's potential to colonize IEC of both host species and the rather mixed reaction patterns observed for all strains under study indicate, that even STEC strains with an unusual genotype as the EHEC O104:H4 outbreak strain, i.e. with an EAEC genetic background, may be able to conquer other reservoir hosts.
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Martorelli L, Garimano N, Fiorentino GA, Vilte DA, Garbaccio SG, Barth SA, Menge C, Ibarra C, Palermo MS, Cataldi A. Efficacy of a recombinant Intimin, EspB and Shiga toxin 2B vaccine in calves experimentally challenged with Escherichia coli O157:H7. Vaccine 2018; 36:3949-3959. [PMID: 29807709 DOI: 10.1016/j.vaccine.2018.05.059] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 05/09/2018] [Accepted: 05/11/2018] [Indexed: 11/30/2022]
Abstract
Escherichia coli O157:H7 is a zoonotic pathogen of global importance and the serotype of Shiga toxin-producing E.coli (STEC) most frequently associated with Hemolytic Uremic Syndrome (HUS) in humans. The main STEC reservoir is cattle. Vaccination of calves with the carboxy-terminal fraction of Intimin γ (IntC280) and EspB can reduce E.coli O157:H7 fecal shedding after experimental challenge. Shiga toxin (Stx) exerts local immunosuppressive effects in the bovine intestine and Stx2B fused to Brucella lumazine synthase (BLS-Stx2B) induces Stx2-neutralizing antibodies. To determine if an immune response against Stx could improve a vaccine's effect on fecal shedding, groups of calves were immunized with EspB + IntC280, with EspB + IntC280 + BLS-Stx2B, or kept as controls. At 24 days post vaccination calves were challenged with E.coli O157:H7. Shedding of E.coli O157:H7 was assessed in recto-anal mucosal swabs by direct plating and enrichment followed by immunomagnetic separation and multiplex PCR. Calves were euthanized 15 days after the challenge and intestinal segments were obtained to assess mucosal antibodies. Vaccination induced a significant increase of IntC280 and EspB specific antibodies in serum and intestinal mucosa in both vaccinated groups. Antibodies against Stx2B were detected in serum and intestinal mucosa of animals vaccinated with 3 antigens. Sera and intestinal homogenates were able to neutralize Stx2 verocytotoxicity compared to the control and the 2-antigens vaccinated group. Both vaccines reduced E.coli O157:H7 shedding compared to the control group. The addition of Stx2B to the vaccine formulation did not result in a superior level of protection compared to the one conferred by IntC280 and EspB alone. It remains to be determined if the inclusion of Stx2B in the vaccine alters E.coli O157:H7 shedding patterns in the long term and after recurrent low dose exposure as occurring in cattle herds.
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Affiliation(s)
- Luisina Martorelli
- Instituto de Patobiología, Centro de Investigación en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Argentina
| | - Nicolás Garimano
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gabriela A Fiorentino
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, (IMEX), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Daniel A Vilte
- Instituto de Patobiología, Centro de Investigación en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Argentina
| | - Sergio G Garbaccio
- Instituto de Patobiología, Centro de Investigación en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Argentina
| | - Stefanie A Barth
- Friedrich-Loeffler-Institut/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany
| | - Christian Menge
- Friedrich-Loeffler-Institut/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany
| | - Cristina Ibarra
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Marina S Palermo
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, (IMEX), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Angel Cataldi
- Instituto de Biotecnología, Centro de Investigación en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria, Hurlingham, Argentina.
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Schmidt N, Barth SA, Frahm J, Meyer U, Dänicke S, Geue L, Menge C. Decreased STEC shedding by cattle following passive and active vaccination based on recombinant Escherichia coli Shiga toxoids. Vet Res 2018. [PMID: 29514704 PMCID: PMC5842637 DOI: 10.1186/s13567-018-0523-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The principal virulence factor of Shiga toxin (Stx)-producing Escherichia coli (STEC), the eponymous Stx, modulates cellular immune responses in cattle, the primary STEC reservoir. We examined whether immunization with genetically inactivated recombinant Shiga toxoids (rStx1MUT/rStx2MUT) influences STEC shedding in a calf cohort. A group of 24 calves was passively (colostrum from immunized cows) and actively (intra-muscularly at 5th and 8th week) vaccinated. Twenty-four calves served as unvaccinated controls (fed with low anti-Stx colostrum, placebo injected). Each group was divided according to the vitamin E concentration they received by milk replacer (moderate and high supplemented). The effective transfer of Stx-neutralizing antibodies from dams to calves via colostrum was confirmed by Vero cell assay. Serum antibody titers in calves differed significantly between the vaccinated and the control group until the 16th week of life. Using the expression of activation marker CD25 on CD4+CD45RO+ cells and CD8αhiCD45RO+ cells as flow cytometry based read-out, cells from vaccinated animals responded more pronounced than those of control calves to lysates of STEC and E. coli strains isolated from the farm as well as to rStx2MUT in the 16th week. Summarized for the entire observation period, less fecal samples from vaccinated calves were stx1 and/or stx2 positive than samples from control animals when calves were fed a moderate amount of vitamin E. This study provides first evidence, that transfer to and induction in young calves of Stx-neutralizing antibodies by Shiga toxoid vaccination offers the opportunity to reduce the incidence of stx-positive fecal samples in a calf cohort.
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Affiliation(s)
- Nadine Schmidt
- Friedrich-Loeffler-Institut (FLI)/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany. .,Justus Liebig Universität Giessen, Institute for Hygiene and Infectious Diseases of Animals, Giessen, Germany.
| | - Stefanie A Barth
- Friedrich-Loeffler-Institut (FLI)/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany
| | - Jana Frahm
- Friedrich-Loeffler-Institut (FLI), Institute of Animal Nutrition, Brunswick, Germany
| | - Ulrich Meyer
- Friedrich-Loeffler-Institut (FLI), Institute of Animal Nutrition, Brunswick, Germany
| | - Sven Dänicke
- Friedrich-Loeffler-Institut (FLI), Institute of Animal Nutrition, Brunswick, Germany
| | - Lutz Geue
- Friedrich-Loeffler-Institut (FLI)/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany
| | - Christian Menge
- Friedrich-Loeffler-Institut (FLI)/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, Jena, Germany
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Steil D, Bonse R, Meisen I, Pohlentz G, Vallejo G, Karch H, Müthing J. A Topographical Atlas of Shiga Toxin 2e Receptor Distribution in the Tissues of Weaned Piglets. Toxins (Basel) 2016; 8:toxins8120357. [PMID: 27916888 PMCID: PMC5198551 DOI: 10.3390/toxins8120357] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 11/21/2016] [Accepted: 11/28/2016] [Indexed: 01/08/2023] Open
Abstract
Shiga toxin (Stx) 2e of Stx-producing Escherichia coli (STEC) is the primary virulence factor in the development of pig edema disease shortly after weaning. Stx2e binds to the globo-series glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer, Galα1-4Galβ1-4Glcβ1-1Cer) and globotetraosylceramide (Gb4Cer, GalNAcβ1-3Galα1-4Galβ1-4Glcβ1-1Cer), the latter acting as the preferential Stx2e receptor. We determined Stx receptor profiles of 25 different tissues of a male and a female weaned piglet using immunochemical solid phase binding assays combined with mass spectrometry. All probed tissues harbored GSL receptors, ranging from high (category I) over moderate (category II) to low content (category III). Examples of Gb4Cer expression in category I tissues are small intestinal ileum, kidney pelvis and whole blood, followed by colon, small intestinal duodenum and jejunum belonging to category II, and kidney cortex, cerebrum and cerebellum as members of category III organs holding true for both genders. Dominant Gb3Cer and Gb4Cer lipoforms were those with ceramides carrying constant sphingosine (d18:1) and a variable C16:0, C22:0 or C24:1/C24:0 fatty acid. From the mapping data, we created a topographical atlas for Stx2e receptors in piglet tissues and organs, which might be helpful to further investigations on the molecular and cellular mechanisms that underlie infections of Stx2e-producing STEC in pigs and their zoonotic potential for humans.
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Affiliation(s)
- Daniel Steil
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.
| | - Robert Bonse
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.
| | - Iris Meisen
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.
| | | | - German Vallejo
- Veterinary practice Dr. med. vet. K. Nolte and Dr. med. vet. G. Vallejo, D-48329 Havixbeck, Germany.
| | - Helge Karch
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.
| | - Johannes Müthing
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.
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Kieckens E, Rybarczyk J, Barth SA, Menge C, Cox E, Vanrompay D. Effect of lactoferrin on release and bioactivity of Shiga toxins from different Escherichia coli O157:H7 strains. Vet Microbiol 2016; 202:29-37. [PMID: 27039884 DOI: 10.1016/j.vetmic.2016.03.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 03/17/2016] [Accepted: 03/22/2016] [Indexed: 11/30/2022]
Abstract
Prevention of enterohemorrhagic Escherichia coli (EHEC) O157:H7 infections and of their severe clinical sequelae in humans remain to be a current challenge. Administration of bovine lactoferrin (bLF) proved to be effective in clearing EHEC from the bovine intestine, an important EHEC reservoir, suggesting that bLF may also be beneficial in human application against EHEC infections. To estimate the biological safety of this approach, we analyzed the effects of bLF on the main EHEC virulence factor, Shiga toxin (Stx). We quantified the release of Stx 1 and 2 from two O157:H7 EHEC strains (Stx1+Stx2+ and Stx2+ producing, respectively) cultured in the presence of bLF using ELISA assays and assessed cytotoxic effects of bLF and co-cultured EHEC on Vero cells. Effects of bLF on the stability of Stx2 were investigated using western blotting. ELISA results indicate a bLF concentration-dependent decrease of active, cell-free Stx2, but not Stx1 in EHEC cultures. High concentrations (100 and 50mg/ml) of bLF resulted in significantly reduced (p<0.05) metabolic activity rates of Vero cells, whereas a concentration of 10mg/ml bLF was considered non-toxic for Vero cells. At concentrations of 1 or 0.1mg/ml, bLF mitigated the verocytotoxicity of EHEC strains in a co-culture model up to 48h after inoculation. When only colonizing bacteria were taken into account, cytotoxicity could be significantly reduced by 10 and 1mg/ml bLF during 48h. This effect of bLF at least partly results from degradation of the Stx2 receptor-binding B-subunit.
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Affiliation(s)
- E Kieckens
- Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
| | - J Rybarczyk
- Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Coupure Links 654, 9000 Gent, Belgium
| | - S A Barth
- Friedrich-Loeffler-Institut, Institute of Molecular Pathogenesis, Naumburger Str. 96a, 07743 Jena, Germany
| | - C Menge
- Friedrich-Loeffler-Institut, Institute of Molecular Pathogenesis, Naumburger Str. 96a, 07743 Jena, Germany
| | - E Cox
- Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - D Vanrompay
- Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Coupure Links 654, 9000 Gent, Belgium
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Menge C, Loos D, Bridger PS, Barth S, Werling D, Baljer G. Bovine macrophages sense Escherichia coli Shiga toxin 1. Innate Immun 2015; 21:655-64. [PMID: 25907071 DOI: 10.1177/1753425915581215] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 03/10/2015] [Indexed: 11/17/2022] Open
Abstract
Shiga toxin (Stx)-producing Escherichia coli (STEC) infections in cattle are asymptomatic; however, Stx impairs the initiation of an adaptive immune response by targeting bovine peripheral and intraepithelial lymphocytes. As presumptive bovine mucosal macrophages (Mø) are also sensitive to Stx, STEC may even exert immune modulatory effects by acting on steps preceding lymphocyte activation at the Mø level. We therefore studied the expression of the Stx receptor (CD77), cellular phenotype and functions after incubation of primary bovine monocyte-derived Mø with purified Stx1. A significant portion of bovine Mø expressed CD77 on their surface, with the recombinant B-subunit of Stx1 binding to >50% of the cells. Stx1 down-regulated significantly surface expression of CD14, CD172a and co-stimulatory molecules CD80 and CD86 within 4 h of incubation, while MHC-II expression remained unaffected. Furthermore, incubation of Mø with Stx1 increased significantly numbers of transcripts for IL-4, IL-6, IL-10, IFN-γ, TNF-α, IL-8 and GRO-α but not for IL-12, TGF-β, MCP-1 and RANTES. In the course of bovine STEC infections, Stx1 appears to induce in Mø a mixed response pattern reminiscent of regulatory Mø, which may amplify the direct suppressive effect of the toxin on lymphocytes.
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Affiliation(s)
- Christian Menge
- Institute of Hygiene and Infectious Diseases of Animals, Justus-Liebig University, Gießen, Germany
| | - Daniela Loos
- Institute of Hygiene and Infectious Diseases of Animals, Justus-Liebig University, Gießen, Germany
| | - Philip S Bridger
- Institute of Hygiene and Infectious Diseases of Animals, Justus-Liebig University, Gießen, Germany
| | - Stefanie Barth
- Institute of Hygiene and Infectious Diseases of Animals, Justus-Liebig University, Gießen, Germany
| | - Dirk Werling
- Royal Veterinary College, Department of Pathology and Pathogen Biology, Hatfield, UK
| | - Georg Baljer
- Institute of Hygiene and Infectious Diseases of Animals, Justus-Liebig University, Gießen, Germany
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11
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Kerner K, Bridger PS, Köpf G, Fröhlich J, Barth S, Willems H, Bauerfeind R, Baljer G, Menge C. Evaluation of biological safety in vitro and immunogenicity in vivo of recombinant Escherichia coli Shiga toxoids as candidate vaccines in cattle. Vet Res 2015; 46:38. [PMID: 25889651 PMCID: PMC4391668 DOI: 10.1186/s13567-015-0175-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 03/26/2015] [Indexed: 12/18/2022] Open
Abstract
Cattle are the most important reservoir for enterohemorrhagic Escherichia coli (EHEC), a subset of shigatoxigenic E. coli (STEC) capable of causing life-threatening infectious diseases in humans. In cattle, Shiga toxins (Stx) suppress the immune system thereby promoting long-term STEC shedding. First infections of animals at calves’ age coincide with the lack of Stx-specific antibodies. We hypothesize that vaccination of calves against Shiga toxins prior to STEC infection may help to prevent the establishment of a persistent type of infection. The objectives of this study were to generate recombinant Shiga toxoids (rStx1mut & rStx2mut) by site-directed mutagenesis and to assess their immunomodulatory, antigenic, and immunogenic properties. Cultures of bovine primary immune cells were used as test systems. In ileal intraepithelial lymphocytes both, recombinant wild type Stx1 (rStx1WT) and rStx2WT significantly induced transcription of IL-4 mRNA. rStx1WT and rStx2WT reduced the expression of Stx-receptor CD77 (syn. Globotriaosylceramide, Gb3) on B and T cells from peripheral blood and of CD14 on monocyte-derived macrophages. At the same concentrations, rStx1mut and rStx2mut exhibited neither of these effects. Antibodies in sera of cattle naturally infected with STEC recognized the rStxmut toxoids equally well as the recombinant wild type toxins. Immunization of calves with rStx1mut plus rStx2mut led to induction of antibodies neutralizing Stx1 and Stx2. While keeping their antigenicity and immunogenicity recombinant Shiga toxoids are devoid of the immunosuppressive properties of the corresponding wild type toxins in cattle and candidate vaccines to mitigate long-term STEC shedding by the reservoir host.
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Affiliation(s)
- Katharina Kerner
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany.
| | - Philip S Bridger
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany.
| | - Gabriele Köpf
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany.
| | - Julia Fröhlich
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany.
| | - Stefanie Barth
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany. .,Current Address: Friedrich-Loeffler-Institut, Institute of Molecular Pathogenesis, Naumburger Str. 96a, 07743, Jena, Germany.
| | - Hermann Willems
- Clinic for Ruminants and Swine (Internal Medicine & Surgery), Justus Liebig University, Giessen, Germany.
| | - Rolf Bauerfeind
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany.
| | - Georg Baljer
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany.
| | - Christian Menge
- Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University, Frankfurter Str. 85-89, 35392, Giessen, Germany. .,Current Address: Friedrich-Loeffler-Institut, Institute of Molecular Pathogenesis, Naumburger Str. 96a, 07743, Jena, Germany.
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Vande Walle K, Vanrompay D, Cox E. Bovine innate and adaptive immune responses against Escherichia coli O157:H7 and vaccination strategies to reduce faecal shedding in ruminants. Vet Immunol Immunopathol 2012; 152:109-20. [PMID: 23084625 DOI: 10.1016/j.vetimm.2012.09.028] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Enterohaemorrhagic E. coli (EHEC) O157:H7 is a zoonotic pathogen of worldwide importance causing foodborne infections with possibly life-threatening consequences in humans, such as haemorrhagic colitis and in a small percentage of zoonotic cases, haemolytic-uremic syndrome (HUS). Ruminants are an important reservoir of EHEC and human infections are most frequently associated with direct or indirect contact with ruminant faeces. A thorough understanding of the host-bacterium interaction in ruminants could lead to the development of novel interventions strategies, including innovative vaccines. This review aims to present the current knowledge regarding innate and adaptive immune responses in EHEC colonized ruminants. In addition, results on vaccination strategies in ruminants aiming at reduction of EHEC shedding are reviewed.
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Affiliation(s)
- Kris Vande Walle
- Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9860 Merelbeke, Belgium
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13
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Maternally and naturally acquired antibodies to Shiga toxins in a cohort of calves shedding Shiga-toxigenic Escherichia coli. Appl Environ Microbiol 2009; 75:3695-704. [PMID: 19363081 DOI: 10.1128/aem.02869-08] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Calves become infected with Shiga toxin-producing Escherichia coli (STEC) early in life, which frequently results in long-term shedding of the zoonotic pathogen. Little is known about the animals' immunological status at the time of infection. We assessed the quantity and dynamics of maternal and acquired antibodies to Shiga toxins (Stx1 and Stx2), the principal STEC virulence factors, in a cohort of 27 calves. Fecal and serum samples were taken repeatedly from birth until the 24th week of age. Sera, milk, and colostrums of dams were also assessed. STEC shedding was confirmed by detection of stx in fecal cultures. Stx1- and Stx2-specific antibodies were quantified by Vero cell neutralization assay and further analyzed by immunoblotting. By the eighth week of age, 13 and 15 calves had at least one stx(1)-type and at least one stx(2)-type positive culture, respectively. Eleven calves had first positive cultures only past that age. Sera and colostrums of all dams and postcolostral sera of all newborn calves contained Stx1-specific antibodies. Calf serum titers decreased rapidly within the first 6 weeks of age. Only five calves showed Stx1-specific seroconversion. Maternal and acquired Stx1-specific antibodies were mainly directed against the StxA1 subunit. Sparse Stx2-specific titers were detectable in sera and colostrums of three dams and in postcolostral sera of their calves. None of the calves developed Stx2-specific seroconversion. The results indicate that under natural conditions of exposure, first STEC infections frequently coincide with an absence of maternal and acquired Stx-specific antibodies in the animals' sera.
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14
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Epithelial and mesenchymal cells in the bovine colonic mucosa differ in their responsiveness to Escherichia coli Shiga toxin 1. Infect Immun 2008; 76:5381-91. [PMID: 18765725 DOI: 10.1128/iai.00553-08] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Bovine colonic crypt cells express CD77 molecules that potentially act as receptors for Shiga toxins (Stx). The implication of this finding for the intestinal colonization of cattle by human pathogenic Stx-producing Escherichia coli (STEC) remains undefined. We used flow cytometric and real-time PCR analyses of primary cultures of colonic crypt cells to evaluate cell viability, CD77 expression, and gene transcription in the presence and absence of purified Stx1. A subset of cultured epithelial cells had Stx receptors which were located mainly intracellularly, with a perinuclear distribution, and were resistant to Stx1-induced apoptosis and Stx1 effects on chemokine expression patterns. In contrast, a population of vimentin-positive cells, i.e., mesenchymal/nonepithelial cells that had high numbers of Stx receptors on their surface, was depleted from the cultures by Stx1. In situ, CD77(+) cells were located in the lamina propria of the bovine colon by using immunofluorescence staining. A newly established vimentin-positive crypt cell line with high CD77 expression resisted the cytolethal effect of Stx1 but responded to Stx1 with a significant increase in interleukin-8 (IL-8), GRO-alpha, MCP-1, and RANTES mRNA. Combined stimulation with lipopolysaccharide and Stx1 increased IL-10 mRNA. Our results show that bovine colonic crypt cells of epithelial origin are resistant to both the cytotoxic and modulatory effects of Stx1. In contrast, some mucosal mesenchymal cells, preliminarily characterized as mucosal macrophages, are Stx1-responsive cells that may participate in the interaction of STEC with the bovine intestinal mucosa.
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15
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Hoffman MA, Menge C, Casey TA, Laegreid W, Bosworth BT, Dean-Nystrom EA. Bovine immune response to shiga-toxigenic Escherichia coli O157:H7. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2006; 13:1322-7. [PMID: 17050743 PMCID: PMC1694447 DOI: 10.1128/cvi.00205-06] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Although cattle develop humoral immune responses to Shiga-toxigenic (Stx+) Escherichia coli O157:H7, infections often result in long-term shedding of these human pathogenic bacteria. The objective of this study was to compare humoral and cellular immune responses to Stx+ and Stx- E. coli O157:H7. Three groups of calves were inoculated intrarumenally, twice in a 3-week interval, with different strains of E. coli: a Stx2-producing E. coli O157:H7 strain (Stx2+ O157), a Shiga toxin-negative E. coli O157:H7 strain (Stx- O157), or a nonpathogenic E. coli strain (control). Fecal shedding of Stx2+ O157 was significantly higher than that of Stx- O157 or the control. Three weeks after the second inoculation, all calves were challenged with Stx2+ O157. Following the challenge, levels of fecal shedding of Stx2+ O157 were similar in all three groups. Both groups inoculated with an O157 strain developed antibodies to O157 LPS. Calves initially inoculated with Stx- O157, but not those inoculated with Stx2+ O157, developed statistically significant lymphoproliferative responses to heat-killed Stx2+ O157. These results provide evidence that infections with STEC can suppress the development of specific cellular immune responses in cattle, a finding that will need to be addressed in designing vaccines against E. coli O157:H7 infections in cattle.
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Affiliation(s)
- Mark A Hoffman
- Enteric Diseases and Food Safety Research, National Disease Center, USDA, Agriculture Research Service, Ames, IA 50010, USA
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16
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Moussay E, Stamm I, Taubert A, Baljer G, Menge C. Escherichia coli Shiga toxin 1 enhances il-4 transcripts in bovine ileal intraepithelial lymphocytes. Vet Immunol Immunopathol 2006; 113:367-82. [PMID: 16879873 DOI: 10.1016/j.vetimm.2006.06.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2006] [Revised: 04/04/2006] [Accepted: 06/19/2006] [Indexed: 11/27/2022]
Abstract
Shiga toxin 1 (Stx1) blocks the activation of bovine peripheral and intraepithelial lymphocytes (IEL), implying that the toxin has the potential to retard the host's immune response during intestinal colonization of cattle with human pathogenic Stx-producing Escherichia coli (STEC). Since Stx1 does not eliminate affected lymphocytes by causing cellular death, we assumed that Stx1 disturbs the integrity of the immune regulatory network. We therefore assessed the impact of Stx1 on the expression of selected chemokine and cytokine genes in vitro by real-time RT-PCR and by quantitation of intracellular cytokine proteins. While Stx1 did not alter the amount of mRNA specific for interleukin (IL)-2, IL-10, gamma interferon (IFN-gamma), transforming growth factor beta (TGF-beta), IL-8, 10kDa interferon inducible protein (IP-10), and monocyte chemoattractant protein 1 (MCP-1) in cultured ileal IEL (iIEL), minute concentrations of Stx1 led to an up to 40-fold increase of il-4 transcripts within 6-8h of incubation. Comparative experiments with peripheral lymphocytes revealed that the effect was specific for iIEL. The enhancement of il-4 transcripts in iIEL was not accompanied by apoptosis but required the enzymatic activity of the holotoxin. Nevertheless, iIEL retained their ability to synthesize proteins in the presence of Stx1: 40% of iIEL could be stimulated to synthesize IFN-gamma while less than 10% expressed IL-4 or TGF-beta. Furthermore, iIEL were found to produce granulocyte chemoattractants, but the release of these substances was not different in iIEL cultures incubated with or without Stx1. Although Stx1 did not affect the numbers of iIEL producing either cytokine, these findings point to an altered responsiveness of IEL during bovine STEC infections and shed light on the initial effects Stx1 exerts on the local adaptive immune system.
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Affiliation(s)
- Etienne Moussay
- Institute for Hygiene and Infectious Diseases of Animals, Frankfurter Strasse 85-89, Justus-Liebig-University, D-35392 Giessen, Germany
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17
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Menge C, Eisenberg T, Stamm I, Baljer G. Comparison of binding and effects of Escherichia coli Shiga toxin 1 on bovine and ovine granulocytes. Vet Immunol Immunopathol 2006; 113:392-403. [PMID: 16884782 DOI: 10.1016/j.vetimm.2006.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Revised: 05/23/2006] [Accepted: 06/26/2006] [Indexed: 11/26/2022]
Abstract
Granulocytes play a pivotal role in the pathogenesis of Shiga toxin (Stx)-producing Escherichia coli (STEC) related diseases in humans. Granulocytes are attracted and activated by Stxs in the enteric mucosa and are believed to thereby contribute to the intestinal inflammation. Mature ruminants, the main reservoir hosts of STEC, do not develop pathological changes that can be attributed to the Stxs. To prove whether the latter phenomenon correlates with the inability of the Stxs to affect granulocytes of ruminants, we investigated the ability of Stx1 to bind to granulocytes of cattle and sheep and analysed the effects of Stx1 on viability, phagocytosis, and oxidative burst activity. Bovine granulocytes from blood and milk did not express Stx1-binding sites even after activation of the cells and also were resistant to Stx1. In contrast to bovine granulocytes, granulocytes of sheep constitutively expressed Stx1-receptors of the Gb(3)/CD77 type ex vivo and bound the recombinant B-subunit of Stx1 (rStxB1). Stx1 holotoxin induced apoptosis in ovine granulocytes after prolonged incubation (18h) but Stx1 only slightly altered the phagocytosis and oxidative burst activities. The rStxB1 had no effect on granulocytes of either species. While arguing in favour of our initial hypothesis, that granulocytes of both, cattle and sheep are not activated by Stxs, the results of our study are the first evidences for differences in the cellular distribution of Stx-receptors in species equally regarded as STEC carriers.
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Affiliation(s)
- Christian Menge
- Institut für Hygiene und Infektionskrankheiten der Tiere, Justus-Liebig-Universität Giessen, Frankfurter Str. 89, D-35392 Giessen, Germany.
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18
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Winter KRK, Stoffregen WC, Dean-Nystrom EA. Shiga toxin binding to isolated porcine tissues and peripheral blood leukocytes. Infect Immun 2004; 72:6680-4. [PMID: 15501802 PMCID: PMC523021 DOI: 10.1128/iai.72.11.6680-6684.2004] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Shiga toxin (Stx) binding sites in porcine tissues and leukocytes were identified by the use of Stx overlay and anti-CD77/Gb3 immunoassays. Stx1 and Stx2 bound to similar tissue locations and leukocytes, although some differences were noted. Previously unreported Stx binding sites were identified in kidney tubules, intestinal lymphoid aggregates, sinusoidal liver cells, alveolar macrophages, and peripheral blood leukocytes.
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Affiliation(s)
- Kellie R K Winter
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, USDA Agricultural Research Service, National Animal Disease Center, Ames 50010-0070, USA
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19
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Menge C, Stamm I, van Diemen PM, Sopp P, Baljer G, Wallis TS, Stevens MP. Phenotypic and functional characterization of intraepithelial lymphocytes in a bovine ligated intestinal loop model of enterohaemorrhagic Escherichia coli infection. J Med Microbiol 2004; 53:573-579. [PMID: 15150340 DOI: 10.1099/jmm.0.45530-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Ruminants are a major reservoir of enterohaemorrhagic Escherichia coli (EHEC), which cause acute gastroenteritis in humans with potentially life-threatening sequelae. The mechanisms underlying EHEC persistence in ruminant hosts are poorly understood. EHEC produce several cytotoxins that inhibit the proliferation of bovine lymphocytes in vitro and influence EHEC persistence in calves, suggesting that bacterial suppression of mucosal inflammation may be important in vivo. In order to address this hypothesis, intraepithelial lymphocytes (IEL) obtained from ligated intestinal loops of five 9-14 day old calves were characterized 12 h after inoculation with E. coli strains. Loops were inoculated with an EHEC O103 : H2 strain, an isogenic Deltastx1 mutant incapable of producing Shiga toxin 1 (Stx1) and a porcine non-pathogenic E. coli strain. The IEL mainly comprised activated CD2(+) CD3(+) CD6(+) CD8alpha(+) T cells and resembled IEL obtained from the intestinal mucosa of orally challenged calves. Forty per cent of all IEL were potentially sensitive to Stx1 in that they expressed the receptor for Stx1. Nevertheless, analysis of IEL from inoculated loops failed to detect a significant effect of the different E. coli strains on proliferative capacity, natural killer cell activity or the cytokine mRNA profile. However, the EHEC wild-type strain reduced the percentage of CD8alpha(+) T cells in the ileal mucosa compared with loops inoculated with the Deltastx1 mutant. This shift in IEL composition was not associated with inhibition of IEL proliferation in situ, since the majority of the IEL from all loops were in the G(0)/G(1) phase of the cell cycle. These studies indicate that the ligated ileal loop model will be a useful tool to dissect the mechanisms underlying suppression of mucosal inflammation by EHEC in the reservoir host.
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Affiliation(s)
- Christian Menge
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-University, D-35392 Giessen, Germany 2,3Division of Microbiology2 and Division of Immunology & Pathology3, Institute for Animal Health, Compton Laboratory, Compton, Berkshire RG20 7NN, UK
| | - Ivonne Stamm
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-University, D-35392 Giessen, Germany 2,3Division of Microbiology2 and Division of Immunology & Pathology3, Institute for Animal Health, Compton Laboratory, Compton, Berkshire RG20 7NN, UK
| | - Pauline M van Diemen
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-University, D-35392 Giessen, Germany 2,3Division of Microbiology2 and Division of Immunology & Pathology3, Institute for Animal Health, Compton Laboratory, Compton, Berkshire RG20 7NN, UK
| | - Paul Sopp
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-University, D-35392 Giessen, Germany 2,3Division of Microbiology2 and Division of Immunology & Pathology3, Institute for Animal Health, Compton Laboratory, Compton, Berkshire RG20 7NN, UK
| | - Georg Baljer
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-University, D-35392 Giessen, Germany 2,3Division of Microbiology2 and Division of Immunology & Pathology3, Institute for Animal Health, Compton Laboratory, Compton, Berkshire RG20 7NN, UK
| | - Timothy S Wallis
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-University, D-35392 Giessen, Germany 2,3Division of Microbiology2 and Division of Immunology & Pathology3, Institute for Animal Health, Compton Laboratory, Compton, Berkshire RG20 7NN, UK
| | - Mark P Stevens
- Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig-University, D-35392 Giessen, Germany 2,3Division of Microbiology2 and Division of Immunology & Pathology3, Institute for Animal Health, Compton Laboratory, Compton, Berkshire RG20 7NN, UK
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Menge C, Blessenohl M, Eisenberg T, Stamm I, Baljer G. Bovine ileal intraepithelial lymphocytes represent target cells for Shiga toxin 1 from Escherichia coli. Infect Immun 2004; 72:1896-905. [PMID: 15039308 PMCID: PMC375150 DOI: 10.1128/iai.72.4.1896-1905.2004] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The discovery that bovine peripheral lymphocytes are sensitive to Stx1 identified a possible mechanism for the persistence of infections with Shiga toxin (Stx)-producing Escherichia coli (STEC) in the bovine reservoir host. If intraepithelial lymphocytes (IEL) are also sensitive to Stx1, the idea that Stx1 affects inflammation in the bovine intestine is highly attractive. To prove this hypothesis, ileal IEL (iIEL) were prepared from adult cattle, characterized by flow cytometry, and subjected to functional assays in the presence and absence of purified Stx1. We found that 14.9% of all iIEL expressed Gb(3)/CD77, the Stx1 receptor on bovine lymphocytes, and 7.9% were able to bind the recombinant B subunit of Stx1. The majority of Gb(3)/CD77(+) cells were activated CD3(+) CD6(+) CD8 alpha(+) T cells, whereas only some CD4(+) T cells and B cells expressed Gb(3)/CD77. However, Stx1 blocked the mitogen-induced transformation to enlarged blast cells within all subpopulations to a similar extent and significantly reduced the percentage of Gb(3)/CD77(+) cells. Although Stx1 did not affect the natural killer cell activity of iIEL, the toxin accelerated the synthesis of interleukin-4 (IL-4) mRNA and reduced the amount of IL-8 mRNA in bovine iIEL cultures. Because the intestinal system comprises a rich network of interactions between different types of cells and any dysfunction may influence the course of intestinal infections, this demonstration that Stx1 can target bovine IEL may be highly relevant for our understanding of the interplay between STEC and its reservoir host.
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Affiliation(s)
- Christian Menge
- Institut für Hygiene und Infektionskrankheiten der Tiere der Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany.
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