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Mosadegh S, Abtahi H, Amani J, Karizi SZ, Salmanian AH. Protective immunization against Enterohemorrhagic Escherichia coli and Shigella dysenteriae Type 1 by chitosan nanoparticle loaded with recombinant chimeric antigens comprising EIT and STX1B-IpaD. Microb Pathog 2023; 184:106344. [PMID: 37704060 DOI: 10.1016/j.micpath.2023.106344] [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: 07/05/2023] [Revised: 09/09/2023] [Accepted: 09/10/2023] [Indexed: 09/15/2023]
Abstract
Increasing evidence demonstrated that Enterohemorrhagic Escherichia coli (EHEC) and Shigella dysenteriae type 1 (S. dysenteriae1) are considered pathogens, that are connected with diarrhea and are still the greatest cause of death in children under the age of five years, worldwide. EHEC and S. dysenteriae 1 infections can be prevented and managed using a vaccination strategy against pathogen attachment stages. In this study, the chitosan nanostructures were loaded with recombinant EIT and STX1B-IpaD polypeptides. The immunogenic properties of this nano-vaccine candidate were investigated. The EIT and STX1B-IpaD recombinant proteins were heterologous expressed, purified, and confirmed by western blotting. The chitosan nanoparticles, were used to encapsulate the purified proteins. The immunogenicity of recombinant nano vaccine candidate, was examined in three groups of BalB/c mice by injection, oral delivery, and combination of oral-injection. ELISA and antibody titer, evaluated the humoral immune response. Finally, all three mice groups were challenged by two pathogens to test the ability of the nano-vaccine candidate to protect against bacterial infection. The Sereny test in guinea pigs was used to confirm the neutralizing effect of immune sera in controlling S. dysenteriae 1, infections. SDS-PAGE and western blotting, confirmed the presence and specificity of 63 and 27 kDa recombinant EIT and STX1B-IpaD, respectively. The results show that the nanoparticles containing recombinant proteins could stimulate the systemic and mucosal immune systems by producing IgG and IgA, respectively. The challenge test showed that, the candidate nano-vaccine could protect the animal model from bacterial infection. The combination of multiple recombinant proteins, carrying several epitopes and natural nanoparticles could evocate remarkable humoral and mucosal responses and improve the protection properties of synthetic antigens. Furthermore, compared with other available antigen delivery methods, using oral delivery as immune priming and injection as a booster method, could act as combinatorial methods to achieve a higher level of immunity. This approach could present an appropriate vaccine candidate against both EHEC and S. dysenteriae 1.
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Affiliation(s)
- Shadi Mosadegh
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Hamid Abtahi
- Molecular and Medicine Research Center, Arak University of Medical Sciences, Arak, Iran
| | - Jafar Amani
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Shohreh Zare Karizi
- Department of Biology, Varamin Pishva Branch, Islamic Azad University, Pishva, Varamin, Iran
| | - Ali Hatef Salmanian
- Department of Agricultural Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
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Targeting the Inside of Cells with Biologicals: Toxin Routes in a Therapeutic Context. BioDrugs 2023; 37:181-203. [PMID: 36729328 PMCID: PMC9893211 DOI: 10.1007/s40259-023-00580-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2023] [Indexed: 02/03/2023]
Abstract
Numerous toxins translocate to the cytosol in order to fulfil their function. This demonstrates the existence of routes for proteins from the extracellular space to the cytosol. Understanding these routes is relevant to multiple aspects related to therapeutic applications. These include the development of anti-toxin treatments, the potential use of toxins as shuttles for delivering macromolecular cargo to the cytosol or the use of drugs based on toxins. Compared with other strategies for delivery, such as chemicals as carriers for macromolecular delivery or physical methods like electroporation, toxin routes present paths into the cell that potentially cause less damage and can be specifically targeted. The efficiency of delivery via toxin routes is limited. However, low-delivery efficiencies can be entirely sufficient, if delivered cargoes possess an amplification effect or if very few molecules are sufficient for inducing the desired effects. This is known for example from RNA-based vaccines that have been developed during the coronavirus disease 2019 pandemic as well as for other approved RNA-based drugs, which elicited the desired effect despite their typically low delivery efficiencies. The different mechanisms by which toxins enter cells may have implications for their technological utility. We review the mechanistic principles of the translocation pathway of toxins from the extracellular space to the cytosol, the delivery efficiencies, and therapeutic strategies or applications that exploit toxin routes for intracellular delivery.
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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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Chiang PY, Adak AK, Liang WL, Tsai CY, Tseng HK, Cheng JY, Hwu JR, Yu AL, Hung JT, Lin CC. Chemoenzymatic Synthesis of Globo-series Glycosphingolipids and Evaluation of Their Immunosuppressive Activities. Chem Asian J 2022; 17:e202200403. [PMID: 35616406 DOI: 10.1002/asia.202200403] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/19/2022] [Indexed: 11/11/2022]
Abstract
Glycosphingolipids (GSLs) play essential roles in many important biological processes, making them attractive synthetic targets. In this paper, a viable chemoenzymatic method is described for the synthesis of globo-series GSLs, namely, Gb4, Gb5, SSEA-4, and Globo H. The strategy uses a chemically synthesized lactoside acceptor equipped with a partial ceramide structure that is uniquely extended by glycosyltransferases in a highly efficient one-pot multiple engyme (OPME) procedure. A direct and quantitative conversion of Gb4 sphingosine to Globo H sphingosine is achieved by performing two-sequential OPME glycosylations. A reduction and N -acylation protocol allows facile incorporation of various fatty acids into the lipid portions of the GSLs. The chemically well-defined lipid-modified Globo H-GSLs displayed some differences in their immunosuprressive activities, which may benefit the structural modifications of Globo h ceramides in finding new types of immunosuppressive agents. The strategy outlined in this work should be applicable to rapid access to other complex GSLs.
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Affiliation(s)
- Pei-Yun Chiang
- National Tsing Hua University, Department of Chemistry, TAIWAN
| | - Avijit K Adak
- National Tsing Hua University, Department of Chemistry, TAIWAN
| | - Wei-Lun Liang
- National Tsing Hua University, Department of Chemistry, TAIWAN
| | - Chen-Yen Tsai
- National Tsing Hua University, Department of Chemistry, TAIWAN
| | - Hsin-Kai Tseng
- National Tsing Hua University, Departemnt of Chemistry, TAIWAN
| | - Jing-Yan Cheng
- Chang Gung University, Institute of Stem Cell and Translational Cancer Research, TAIWAN
| | - Jih Ru Hwu
- National Tsing Hua University, Department of Chemistry, TAIWAN
| | - Alice L Yu
- Chang Gung University, Institute of Stem Cell and Translational Cancer Research, TAIWAN
| | - Jung-Tung Hung
- Chang Gung University, Institute of Stem Cell and Translational Cancer Research, TAIWAN
| | - Chun-Cheng Lin
- National Tsing Hua University, Department of chemistry, 101 Sec. 2, Kuang Fu Rd, 30013, Hsinchu, TAIWAN
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Murai Y, Yuyama K, Mikami D, Igarashi Y, Monde K. Penta-deuterium-labeled 4E, 8Z-sphingadienine for rapid analysis in sphingolipidomics study. Chem Phys Lipids 2022; 245:105202. [PMID: 35337796 DOI: 10.1016/j.chemphyslip.2022.105202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/01/2022] [Accepted: 03/18/2022] [Indexed: 12/28/2022]
Abstract
The use of deuterium-incorporated bioactive compounds is an efficient method for tracing their metabolic fate and for quantitative analysis by mass spectrometry without complicated HPLC separation even if their amounts are extremely small. Plant sphingolipids and their metabolites, which have C4, 8-olefins on a common backbone as a sphingoid base, show unique and fascinating bioactivities compared to those of sphingolipids in mammals. However, the functional and metabolic mechanisms of exogenous plant sphingolipids have not been elucidated due to the difficulty in distinguishing exogenous sphingolipids from endogenous sphingolipids having the same polarity and same molecular weight by mass spectrometric analysis. Their roles might be elucidated by the use of deuterated probes with original biological and physicochemical properties. In this study, we designed (2S,3R,4E,8Z)-2-aminooctadeca-4,8-diene-17,17,18,18,18-d5-1,3-diol (penta-deuterium-labeled 4E, 8Z-sphingadienine) as a tracer for exogenous metabolic studies. In addition, the sphingadienine was confirmed to be metabolized in HEK293 cells and showed distinct peaks in mass spectrometric analysis.
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Affiliation(s)
- Yuta Murai
- Graduate School of Life Science, Kita 21 Nishi 11, Sapporo 001-0021, Japan; Faculty of Advanced Life Science, Hokkaido University, Kita 21 Nishi 11, Sapporo 001-0021, Japan.
| | - Kohei Yuyama
- Lipid Biofunction Section, Faculty of Advanced Life Science, Hokkaido University, Kita-21, Nishi-11, Kita-ku, Sapporo 001-0021, Japan
| | - Daisuke Mikami
- Lipid Biofunction Section, Faculty of Advanced Life Science, Hokkaido University, Kita-21, Nishi-11, Kita-ku, Sapporo 001-0021, Japan
| | - Yasuyuki Igarashi
- Lipid Biofunction Section, Faculty of Advanced Life Science, Hokkaido University, Kita-21, Nishi-11, Kita-ku, Sapporo 001-0021, Japan
| | - Kenji Monde
- Graduate School of Life Science, Kita 21 Nishi 11, Sapporo 001-0021, Japan; Faculty of Advanced Life Science, Hokkaido University, Kita 21 Nishi 11, Sapporo 001-0021, Japan.
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Luz D, Gómez FD, Ferreira RL, Melo BS, Guth BEC, Quintilio W, Moro AM, Presta A, Sacerdoti F, Ibarra C, Chen G, Sidhu SS, Amaral MM, Piazza RMF. The Deleterious Effects of Shiga Toxin Type 2 Are Neutralized In Vitro by FabF8:Stx2 Recombinant Monoclonal Antibody. Toxins (Basel) 2021; 13:toxins13110825. [PMID: 34822608 PMCID: PMC8621789 DOI: 10.3390/toxins13110825] [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: 10/14/2021] [Revised: 11/10/2021] [Accepted: 11/15/2021] [Indexed: 12/26/2022] Open
Abstract
Hemolytic Uremic Syndrome (HUS) associated with Shiga-toxigenic Escherichia coli (STEC) infections is the principal cause of acute renal injury in pediatric age groups. Shiga toxin type 2 (Stx2) has in vitro cytotoxic effects on kidney cells, including human glomerular endothelial (HGEC) and Vero cells. Neither a licensed vaccine nor effective therapy for HUS is available for humans. Recombinant antibodies against Stx2, produced in bacteria, appeared as the utmost tool to prevent HUS. Therefore, in this work, a recombinant FabF8:Stx2 was selected from a human Fab antibody library by phage display, characterized, and analyzed for its ability to neutralize the Stx activity from different STEC-Stx2 and Stx1/Stx2 producing strains in a gold standard Vero cell assay, and the Stx2 cytotoxic effects on primary cultures of HGEC. This recombinant Fab showed a dissociation constant of 13.8 nM and a half maximum effective concentration (EC50) of 160 ng/mL to Stx2. Additionally, FabF8:Stx2 neutralized, in different percentages, the cytotoxic effects of Stx2 and Stx1/2 from different STEC strains on Vero cells. Moreover, it significantly prevented the deleterious effects of Stx2 in a dose-dependent manner (up to 83%) in HGEC and protected this cell up to 90% from apoptosis and necrosis. Therefore, this novel and simple anti-Stx2 biomolecule will allow further investigation as a new therapeutic option that could improve STEC and HUS patient outcomes.
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Affiliation(s)
- Daniela Luz
- Laboratório de Bacteriologia, Instituto Butantan, Sao Paulo 05503-900, Brazil; (D.L.); (R.L.F.); (B.S.M.)
| | - Fernando D. Gómez
- Laboratorio de Fisiopatogenia, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires 1121, Argentina; (F.D.G.); (A.P.); (F.S.); (C.I.)
| | - Raíssa L. Ferreira
- Laboratório de Bacteriologia, Instituto Butantan, Sao Paulo 05503-900, Brazil; (D.L.); (R.L.F.); (B.S.M.)
| | - Bruna S. Melo
- Laboratório de Bacteriologia, Instituto Butantan, Sao Paulo 05503-900, Brazil; (D.L.); (R.L.F.); (B.S.M.)
| | - Beatriz E. C. Guth
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de Sāo Paulo, Sao Paulo 04023-062, Brazil;
| | - Wagner Quintilio
- Laboratório de Biofármacos, Instituto Butantan, Sao Paulo 05503-900, Brazil; (W.Q.); (A.M.M.)
| | - Ana Maria Moro
- Laboratório de Biofármacos, Instituto Butantan, Sao Paulo 05503-900, Brazil; (W.Q.); (A.M.M.)
| | - Agostina Presta
- Laboratorio de Fisiopatogenia, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires 1121, Argentina; (F.D.G.); (A.P.); (F.S.); (C.I.)
| | - Flavia Sacerdoti
- Laboratorio de Fisiopatogenia, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires 1121, Argentina; (F.D.G.); (A.P.); (F.S.); (C.I.)
| | - Cristina Ibarra
- Laboratorio de Fisiopatogenia, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires 1121, Argentina; (F.D.G.); (A.P.); (F.S.); (C.I.)
| | - Gang Chen
- Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, OT M5S 3E1, Canada; (G.C.); (S.S.S.)
| | - Sachdev S. Sidhu
- Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, OT M5S 3E1, Canada; (G.C.); (S.S.S.)
| | - María Marta Amaral
- Laboratorio de Fisiopatogenia, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires 1121, Argentina; (F.D.G.); (A.P.); (F.S.); (C.I.)
- Correspondence: (M.M.A.); (R.M.F.P.)
| | - Roxane M. F. Piazza
- Laboratório de Bacteriologia, Instituto Butantan, Sao Paulo 05503-900, Brazil; (D.L.); (R.L.F.); (B.S.M.)
- Correspondence: (M.M.A.); (R.M.F.P.)
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Koeppel MB, Glaser J, Baumgartner T, Spriewald S, Gerlach RG, von Armansperg B, Leong JM, Stecher B. Scalable Reporter Assays to Analyze the Regulation of stx2 Expression in Shiga Toxin-Producing Enteropathogens. Toxins (Basel) 2021; 13:toxins13080534. [PMID: 34437405 PMCID: PMC8402550 DOI: 10.3390/toxins13080534] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 12/02/2022] Open
Abstract
Stx2 is the major virulence factor of EHEC and is associated with an increased risk for HUS in infected patients. The conditions influencing its expression in the intestinal tract are largely unknown. For optimal management and treatment of infected patients, the identification of environmental conditions modulating Stx2 levels in the human gut is of central importance. In this study, we established a set of chromosomal stx2 reporter assays. One system is based on superfolder GFP (sfGFP) using a T7 polymerase/T7 promoter-based amplification loop. This reporter can be used to analyze stx2 expression at the single-cell level using FACSs and fluorescence microscopy. The other system is based on the cytosolic release of the Gaussia princeps luciferase (gluc). This latter reporter proves to be a highly sensitive and scalable reporter assay that can be used to quantify reporter protein in the culture supernatant. We envision that this new set of reporter tools will be highly useful to comprehensively analyze the influence of environmental and host factors, including drugs, small metabolites and the microbiota, on Stx2 release and thereby serve the identification of risk factors and new therapies in Stx-mediated pathologies.
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Affiliation(s)
- Martin B. Koeppel
- Max-von-Pettenkofer Institute, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; (J.G.); (T.B.); (S.S.); (B.v.A.)
- German Center for Infection Research (DZIF), Partner Site LMU Munich, 80336 Munich, Germany
- Correspondence: (M.B.K.); (B.S.)
| | - Jana Glaser
- Max-von-Pettenkofer Institute, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; (J.G.); (T.B.); (S.S.); (B.v.A.)
- German Center for Infection Research (DZIF), Partner Site LMU Munich, 80336 Munich, Germany
| | - Tobias Baumgartner
- Max-von-Pettenkofer Institute, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; (J.G.); (T.B.); (S.S.); (B.v.A.)
- German Center for Infection Research (DZIF), Partner Site LMU Munich, 80336 Munich, Germany
| | - Stefanie Spriewald
- Max-von-Pettenkofer Institute, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; (J.G.); (T.B.); (S.S.); (B.v.A.)
- German Center for Infection Research (DZIF), Partner Site LMU Munich, 80336 Munich, Germany
| | - Roman G. Gerlach
- Mikrobiologisches Institut-Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen and Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Wasserturmstraße 3/5, 91054 Erlangen, Germany;
| | - Benedikt von Armansperg
- Max-von-Pettenkofer Institute, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; (J.G.); (T.B.); (S.S.); (B.v.A.)
- German Center for Infection Research (DZIF), Partner Site LMU Munich, 80336 Munich, Germany
| | - John M. Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Ave, Boston, MA 02111, USA;
| | - Bärbel Stecher
- Max-von-Pettenkofer Institute, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; (J.G.); (T.B.); (S.S.); (B.v.A.)
- German Center for Infection Research (DZIF), Partner Site LMU Munich, 80336 Munich, Germany
- Correspondence: (M.B.K.); (B.S.)
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Detzner J, Klein AL, Pohlentz G, Krojnewski E, Humpf HU, Mellmann A, Karch H, Müthing J. Primary Human Renal Proximal Tubular Epithelial Cells (pHRPTEpiCs): Shiga Toxin (Stx) Glycosphingolipid Receptors, Stx Susceptibility, and Interaction with Membrane Microdomains. Toxins (Basel) 2021; 13:toxins13080529. [PMID: 34437399 PMCID: PMC8402424 DOI: 10.3390/toxins13080529] [Citation(s) in RCA: 4] [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: 05/19/2021] [Revised: 07/20/2021] [Accepted: 07/23/2021] [Indexed: 12/13/2022] Open
Abstract
Tubular epithelial cells of the human kidney are considered as targets of Shiga toxins (Stxs) in the Stx-mediated pathogenesis of hemolytic–uremic syndrome (HUS) caused by Stx-releasing enterohemorrhagic Escherichia coli (EHEC). Analysis of Stx-binding glycosphingolipids (GSLs) of primary human renal proximal tubular epithelial cells (pHRPTEpiCs) yielded globotriaosylceramide (Gb3Cer) and globotetraosylceramide (Gb4Cer) with Cer (d18:1, C16:0), Cer (d18:1, C22:0), and Cer (d18:1, C24:1/C24:0) as the dominant lipoforms. Investigation of detergent-resistant membranes (DRMs) and nonDRMs, serving as equivalents for the liquid-ordered and liquid-disordered membrane phase, respectively, revealed the prevalence of Gb3Cer and Gb4Cer together with cholesterol and sphingomyelin in DRMs, suggesting lipid raft association. Stx1a and Stx2a exerted strong cellular damage with half-maximal cytotoxic doses (CD50) of 1.31 × 102 pg/mL and 1.66 × 103 pg/mL, respectively, indicating one order of magnitude higher cellular cytotoxicity of Stx1a. Surface acoustic wave (SAW) real-time interaction analysis using biosensor surfaces coated with DRM or nonDRM fractions gave stronger binding capability of Stx1a versus Stx2a that correlated with the lower cytotoxicity of Stx2a. Our study underlines the substantial role of proximal tubular epithelial cells of the human kidney being associated with the development of Stx-mediated HUS at least for Stx1a, while the impact of Stx2a remains somewhat ambiguous.
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Affiliation(s)
- Johanna Detzner
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (A.-L.K.); (G.P.); (E.K.); (A.M.); (H.K.)
| | - Anna-Lena Klein
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (A.-L.K.); (G.P.); (E.K.); (A.M.); (H.K.)
| | - Gottfried Pohlentz
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (A.-L.K.); (G.P.); (E.K.); (A.M.); (H.K.)
| | - Elisabeth Krojnewski
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (A.-L.K.); (G.P.); (E.K.); (A.M.); (H.K.)
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, University of Münster, D-48149 Münster, Germany;
| | - Alexander Mellmann
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (A.-L.K.); (G.P.); (E.K.); (A.M.); (H.K.)
| | - Helge Karch
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (A.-L.K.); (G.P.); (E.K.); (A.M.); (H.K.)
| | - Johannes Müthing
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (A.-L.K.); (G.P.); (E.K.); (A.M.); (H.K.)
- Correspondence:
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9
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Johannes L. The Cellular and Chemical Biology of Endocytic Trafficking and Intracellular Delivery-The GL-Lect Hypothesis. Molecules 2021; 26:3299. [PMID: 34072622 PMCID: PMC8198588 DOI: 10.3390/molecules26113299] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 04/27/2021] [Accepted: 05/06/2021] [Indexed: 12/31/2022] Open
Abstract
Lipid membranes are common to all forms of life. While being stable barriers that delimitate the cell as the fundamental organismal unit, biological membranes are highly dynamic by allowing for lateral diffusion, transbilayer passage via selective channels, and in eukaryotic cells for endocytic uptake through the formation of membrane bound vesicular or tubular carriers. Two of the most abundant fundamental fabrics of membranes-lipids and complex sugars-are produced through elaborate chains of biosynthetic enzymes, which makes it difficult to study them by conventional reverse genetics. This review illustrates how organic synthesis provides access to uncharted areas of membrane glycobiology research and its application to biomedicine. For this Special Issue on Chemical Biology Research in France, focus will be placed on synthetic approaches (i) to study endocytic functions of glycosylated proteins and lipids according to the GlycoLipid-Lectin (GL-Lect) hypothesis, notably that of Shiga toxin; (ii) to mechanistically dissect its endocytosis and intracellular trafficking with small molecule; and (iii) to devise intracellular delivery strategies for immunotherapy and tumor targeting. It will be pointed out how the chemical biologist's view on lipids, sugars, and proteins synergizes with biophysics and modeling to "look" into the membrane for atomistic scale insights on molecular rearrangements that drive the biogenesis of endocytic carriers in processes of clathrin-independent endocytosis.
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Affiliation(s)
- Ludger Johannes
- Cellular and Chemical Biology Department, Institut Curie, PSL Research University, U1143 INSERM, UMR3666 CNRS, 26 rue d'Ulm, CEDEX 05, 75248 Paris, France
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10
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Peng XP, Ding W, Ma JM, Zhang J, Sun J, Cao Y, Lei LH, Zhao J, Li YF. Effect of Escherichia Coli Infection on Metabolism of Dietary Protein in Intestine. Curr Protein Pept Sci 2021; 21:772-776. [PMID: 31724511 DOI: 10.2174/1389203720666191113144049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 07/26/2019] [Accepted: 09/23/2019] [Indexed: 11/22/2022]
Abstract
Dietary proteins are linked to the pathogenic Escherichia coli (E. coli) through the intestinal tract, which is the site where both dietary proteins are metabolized and pathogenic E. coli strains play a pathogenic role. Dietary proteins are degraded by enzymes in the intestine lumen and their metabolites are transferred into enterocytes to be further metabolized. Seven diarrheagenic E. coli pathotypes have been identified, and they damage the intestinal epithelium through physical injury and effector proteins, which lead to inhibit the digestibility and absorption of dietary proteins in the intestine tract. But the increased tryptophan (Trp) content in the feed, low-protein diet or milk fractions supplementation is effective in preventing and controlling infections by pathogenic E. coli in the intestine.
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Affiliation(s)
- Xiao-Pei Peng
- Department of Animal Husbandry and Veterinary Medicine, Beijing Vocational College of Agriculture, Beijing, China
| | - Wei Ding
- Department of Gerontology, Shanghai General Hospital, Shanghai Jiao Tong University, China
| | - Jian-Min Ma
- Department of Animal Husbandry and Veterinary Medicine, Beijing Vocational College of Agriculture, Beijing, China
| | - Jie Zhang
- Department of Animal Husbandry and Veterinary Medicine, Beijing Vocational College of Agriculture, Beijing, China
| | - Jian Sun
- Department of Animal Husbandry and Veterinary Medicine, Beijing Vocational College of Agriculture, Beijing, China
| | - Yun Cao
- Department of Animal Husbandry and Veterinary Medicine, Beijing Vocational College of Agriculture, Beijing, China
| | - Li-Hui Lei
- Department of Animal Husbandry and Veterinary Medicine, Beijing Vocational College of Agriculture, Beijing, China
| | - Jinshan Zhao
- College of Animal Science and Technology, Qingdao Agricultural University, Shandong, China
| | - Yun-Fu Li
- Beijing Vocational College of Agriculture, Beijing, China
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11
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The Protein Toxins Ricin and Shiga Toxin as Tools to Explore Cellular Mechanisms of Internalization and Intracellular Transport. Toxins (Basel) 2021; 13:toxins13060377. [PMID: 34070659 PMCID: PMC8227415 DOI: 10.3390/toxins13060377] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/12/2021] [Accepted: 05/22/2021] [Indexed: 12/18/2022] Open
Abstract
Protein toxins secreted by bacteria and found in plants can be threats to human health. However, their extreme toxicity can also be exploited in different ways, e.g., to produce hybrid toxins directed against cancer cells and to study transport mechanisms in cells. Investigations during the last decades have shown how powerful these molecules are as tools in cell biological research. Here, we first present a partly historical overview, with emphasis on Shiga toxin and ricin, of how such toxins have been used to characterize processes and proteins of importance for their trafficking. In the second half of the article, we describe how one can now use toxins to investigate the role of lipid classes for intracellular transport. In recent years, it has become possible to quantify hundreds of lipid species using mass spectrometry analysis. Thus, it is also now possible to explore the importance of lipid species in intracellular transport. The detailed analyses of changes in lipids seen under conditions of inhibited toxin transport reveal previously unknown connections between syntheses of lipid classes and demonstrate the ability of cells to compensate under given conditions.
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12
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Detzner J, Krojnewski E, Pohlentz G, Steil D, Humpf HU, Mellmann A, Karch H, Müthing J. Shiga Toxin (Stx)-Binding Glycosphingolipids of Primary Human Renal Cortical Epithelial Cells (pHRCEpiCs) and Stx-Mediated Cytotoxicity. Toxins (Basel) 2021; 13:toxins13020139. [PMID: 33673393 PMCID: PMC7918848 DOI: 10.3390/toxins13020139] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/03/2021] [Accepted: 02/04/2021] [Indexed: 12/12/2022] Open
Abstract
Human kidney epithelial cells are supposed to be directly involved in the pathogenesis of the hemolytic–uremic syndrome (HUS) caused by Shiga toxin (Stx)-producing enterohemorrhagic Escherichia coli (EHEC). The characterization of the major and minor Stx-binding glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer) and globotetraosylceramide (Gb4Cer), respectively, of primary human renal cortical epithelial cells (pHRCEpiCs) revealed GSLs with Cer (d18:1, C16:0), Cer (d18:1, C22:0), and Cer (d18:1, C24:1/C24:0) as the dominant lipoforms. Using detergent-resistant membranes (DRMs) and non-DRMs, Gb3Cer and Gb4Cer prevailed in the DRM fractions, suggesting their association with microdomains in the liquid-ordered membrane phase. A preference of Gb3Cer and Gb4Cer endowed with C24:0 fatty acid accompanied by minor monounsaturated C24:1-harboring counterparts was observed in DRMs, whereas the C24:1 fatty acid increased in relation to the saturated equivalents in non-DRMs. A shift of the dominant phospholipid phosphatidylcholine with saturated fatty acids in the DRM to unsaturated species in the non-DRM fractions correlated with the GSL distribution. Cytotoxicity assays gave a moderate susceptibility of pHRCEpiCs to the Stx1a and Stx2a subtypes when compared to highly sensitive Vero-B4 cells. The results indicate that presence of Stx-binding GSLs per se and preferred occurrence in microdomains do not necessarily lead to a high cellular susceptibility towards Stx.
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Affiliation(s)
- Johanna Detzner
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (E.K.); (G.P.); (D.S.); (A.M.); (H.K.)
| | - Elisabeth Krojnewski
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (E.K.); (G.P.); (D.S.); (A.M.); (H.K.)
| | - Gottfried Pohlentz
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (E.K.); (G.P.); (D.S.); (A.M.); (H.K.)
| | - Daniel Steil
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (E.K.); (G.P.); (D.S.); (A.M.); (H.K.)
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, University of Münster, D-48149 Münster, Germany;
| | - Alexander Mellmann
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (E.K.); (G.P.); (D.S.); (A.M.); (H.K.)
| | - Helge Karch
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (E.K.); (G.P.); (D.S.); (A.M.); (H.K.)
| | - Johannes Müthing
- Institute of Hygiene, University of Münster, D-48149 Münster, Germany; (J.D.); (E.K.); (G.P.); (D.S.); (A.M.); (H.K.)
- Correspondence:
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13
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Bosso A, Di Maro A, Cafaro V, Di Donato A, Notomista E, Pizzo E. Enzymes as a Reservoir of Host Defence Peptides. Curr Top Med Chem 2021; 20:1310-1323. [PMID: 32223733 DOI: 10.2174/1568026620666200327173815] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/21/2020] [Accepted: 03/11/2020] [Indexed: 12/16/2022]
Abstract
Host defence peptides (HDPs) are powerful modulators of cellular responses to various types of insults caused by pathogen agents. To date, a wide range of HDPs, from species of different kingdoms including bacteria, plant and animal with extreme diversity in structure and biological activity, have been described. Apart from a limited number of peptides ribosomally synthesized, a large number of promising and multifunctional HDPs have been identified within protein precursors, with properties not necessarily related to innate immunity, consolidating the fascinating hypothesis that proteins have a second or even multiple biological mission in the form of one or more bio-active peptides. Among these precursors, enzymes constitute certainly an interesting group, because most of them are mainly globular and characterized by a fine specific internal structure closely related to their catalytic properties and also because they are yet little considered as potential HDP releasing proteins. In this regard, the main aim of the present review is to describe a panel of HDPs, identified in all canonical classes of enzymes, and to provide a detailed description on hydrolases and their corresponding HDPs, as there seems to exist a striking link between these structurally sophisticated catalysts and their high content in cationic and amphipathic cryptic peptides.
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Affiliation(s)
- Andrea Bosso
- Department of Biology, University of Naples 'Federico II', Naples, Italy
| | - Antimo Di Maro
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), University of Campania 'Luigi Vanvitelli', Caserta, Italy
| | - Valeria Cafaro
- Department of Biology, University of Naples 'Federico II', Naples, Italy
| | - Alberto Di Donato
- Department of Biology, University of Naples 'Federico II', Naples, Italy
| | - Eugenio Notomista
- Department of Biology, University of Naples 'Federico II', Naples, Italy
| | - Elio Pizzo
- Department of Biology, University of Naples 'Federico II', Naples, Italy
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14
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Rohokale RS, Li Q, Guo Z. A Diversity-Oriented Strategy for Chemical Synthesis of Glycosphingolipids: Synthesis of Glycosphingolipid LcGg4 and Its Analogues and Derivatives. J Org Chem 2021; 86:1633-1648. [PMID: 33395290 DOI: 10.1021/acs.joc.0c02490] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A diversity-oriented strategy was developed for the synthesis of glycosphingolipids (GSLs). This strategy was highlighted by using a simple lactoside containing the core structures of GSL glycan and lipid as the universal starting material to obtain different synthetic targets upon stepwise elongation of the glycan via chemical glycosylations and on-site remodeling of the lipid via chemoselective cross-metathesis and N-acylation. The strategy was verified with the synthesis of a lacto-ganglio GSL, LcGg4, which is a biomarker of undifferentiated malignant myeloid cells, and a series of its analogues or derivatives carrying different sugar chains and unique functionalities or molecular labels. This synthetic strategy should be widely applicable and, therefore, be utilized to rapidly access various GSLs and related derivatives by using different donors for glycosylations and different substrates for lipid remodeling following each glycosylation.
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Affiliation(s)
- Rajendra S Rohokale
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Qingjiang Li
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
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15
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Szymczak-Kulus K, Weidler S, Bereznicka A, Mikolajczyk K, Kaczmarek R, Bednarz B, Zhang T, Urbaniak A, Olczak M, Park EY, Majorczyk E, Kapczynska K, Lukasiewicz J, Wuhrer M, Unverzagt C, Czerwinski M. Human Gb3/CD77 synthase produces P1 glycotope-capped N-glycans, which mediate Shiga toxin 1 but not Shiga toxin 2 cell entry. J Biol Chem 2021; 296:100299. [PMID: 33460651 PMCID: PMC7949097 DOI: 10.1016/j.jbc.2021.100299] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/07/2021] [Accepted: 01/12/2021] [Indexed: 12/15/2022] Open
Abstract
The human Gb3/CD77 synthase, encoded by the A4GALT gene, is an unusually promiscuous glycosyltransferase. It synthesizes the Galα1→4Gal linkage on two different glycosphingolipids (GSLs), producing globotriaosylceramide (Gb3, CD77, Pk) and the P1 antigen. Gb3 is the major receptor for Shiga toxins (Stxs) produced by enterohemorrhagic Escherichia coli. A single amino acid substitution (p.Q211E) ramps up the enzyme's promiscuity, rendering it able to attach Gal both to another Gal residue and to GalNAc, giving rise to NOR1 and NOR2 GSLs. Human Gb3/CD77 synthase was long believed to transfer Gal only to GSL acceptors, therefore its GSL products were, by default, considered the only human Stx receptors. Here, using soluble, recombinant human Gb3/CD77 synthase and p.Q211E mutein, we demonstrate that both enzymes can synthesize the P1 glycotope (terminal Galα1→4Galβ1→4GlcNAc-R) on a complex type N-glycan and a synthetic N-glycoprotein (saposin D). Moreover, by transfection of CHO-Lec2 cells with vectors encoding human Gb3/CD77 synthase and its p.Q211E mutein, we demonstrate that both enzymes produce P1 glycotopes on N-glycoproteins, with the mutein exhibiting elevated activity. These P1-terminated N-glycoproteins are recognized by Stx1 but not Stx2 B subunits. Finally, cytotoxicity assays show that Stx1 can use P1 N-glycoproteins produced in CHO-Lec2 cells as functional receptors. We conclude that Stx1 can recognize and use P1 N-glycoproteins in addition to its canonical GSL receptors to enter and kill the cells, while Stx2 can use GSLs only. Collectively, these results may have important implications for our understanding of the Shiga toxin pathology.
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Affiliation(s)
- Katarzyna Szymczak-Kulus
- Laboratory of Glycobiology, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland
| | - Sascha Weidler
- Department of Bioorganic Chemistry, University of Bayreuth, Bayreuth, Germany
| | - Anna Bereznicka
- Laboratory of Glycobiology, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland
| | - Krzysztof Mikolajczyk
- Laboratory of Glycobiology, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland
| | - Radoslaw Kaczmarek
- Laboratory of Glycobiology, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland
| | - Bartosz Bednarz
- Laboratory of Molecular Biology of Microorganisms, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland
| | - Tao Zhang
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Anna Urbaniak
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
| | - Mariusz Olczak
- Department of Biochemistry, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Enoch Y Park
- Laboratory of Biotechnology, Shizuoka University, Shizuoka, Japan
| | - Edyta Majorczyk
- Faculty of Physical Education and Physiotherapy, Opole University of Technology, Opole, Poland
| | - Katarzyna Kapczynska
- Laboratory of Medical Microbiology, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland
| | - Jolanta Lukasiewicz
- Laboratory of Microbial Immunochemistry and Vaccines, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Carlo Unverzagt
- Department of Bioorganic Chemistry, University of Bayreuth, Bayreuth, Germany
| | - Marcin Czerwinski
- Laboratory of Glycobiology, Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland.
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16
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Calò LA, Davis PA. Are the Clinical Presentations (Phenotypes) of Gitelman's and Bartter's Syndromes Gene Mutations Driven by Their Effects on Intracellular pH, Their "pH" Enotype? Int J Mol Sci 2020; 21:E5660. [PMID: 32784543 PMCID: PMC7460608 DOI: 10.3390/ijms21165660] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 07/29/2020] [Accepted: 08/05/2020] [Indexed: 12/14/2022] Open
Abstract
Gitelman's syndrome (GS) and Bartter's syndrome (BS) are rare inherited salt-losing tubulopathies whose variations in genotype do not correlate well with either clinical course or electrolyte requirements. Using GS/BS patients as nature's experiments, we found them to be a human model of endogenous Ang II antagonism with activated Renin-Angiotensin System (RAS), resulting in high Ang II levels with blunted cardiovascular effects. These patients are also characterized by increased and directly correlated levels of both Angiotensin Converting Enzyme 2 (ACE2) and Ang 1-7. Understanding the myriad of distinctive and frequently overlapping clinical presentations of GS/BS arises remains challenging. Efforts to find a treatment for COVID-19 has fueled a recent surge in interest in chloroquine/hydroxychloroquine and its effects. Of specific interest are chloroquine/hydroxychloroquine's ability to inhibit SARS-CoV infection by impairing ACE2, the SARS-CoV2 entry point, through terminal glycosylation via effects on TGN/post-Golgi pH homeostasis. Several different studies with a GS or a BS phenotype, along with a nonsyndromic form of X-linked intellectual disability linked to a mutated SLC9A7, provide additional evidence that specific gene defects can act via misregulation of TGN/post-Golgi pH homeostasis, which leads to a common mechanistic basis resulting in overlapping phenotypes. We suggest that linkage between the specific gene defects identified in GS and BS and the myriad of distinctive and frequently overlapping clinical findings may be the result of aberrant glycosylation of ACE2 driven by altered TGN/endosome system acidification caused by the metabolic alkalosis brought about by these salt-losing tubulopathies in addition to their altered intracellular calcium signaling due to a blunted second messenger induced intracellular calcium release that is, in turn, amplified by the RAS system.
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Affiliation(s)
- Lorenzo A Calò
- Nephrology, Dialysis and Transplantation Unit, Department of Medicine, University of Padova, 35128 Padova, Italy
| | - Paul A Davis
- Department of Nutrition, University of California at Davis, Davis, CA 95616, USA;
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17
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Kaur H, Shorie M, Sabherwal P. Biolayer interferometry-SELEX for Shiga toxin antigenic-peptide aptamers & detection via chitosan-WSe 2 aptasensor. Biosens Bioelectron 2020; 167:112498. [PMID: 32814208 DOI: 10.1016/j.bios.2020.112498] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 12/12/2022]
Abstract
We report biolayer interferometry based in-vitro selection technique (BLI-SELEX) for fishing out specific aptamers against E. coli Shiga toxin subtypes viz., stx1 & stx2 via epitopic peptides. BLI-SELEX is a one-step technique for rapidly generating aptamers against protein biomarkers in a microtiter plate format, obliterating the need for multiple enrichment rounds to harvest high-affinity aptamers as in conventional SELEX. Two unique aptamers selected against stx1 & stx2 with picomolar Kd (~47 pM & ~29 pM, respectively) were successfully used to fabricate voltammetric diagnostic assay via immobilization onto chitosan exfoliated 2D tungsten diselenide (WSe2) nanosheet platform. These aptamers modified nanosensors showed high sensitivity of ~ 5.0 μA ng-1 mL, a dynamic response range from 50 pg mL-1 to 100 ng mL-1, with a detection limit of 44.5 pg mL-1 & 41.3 pg mL-1 for stx subtypes, respectively and showed low cross-reactivity in spiked urine, serum and milk samples. The synergistic effect of selective aptamers & high sensitivity imparted by 2D transition metal dichalcogenide (TMD) highlights the superior potential of a fabricated nanosensor for bacterial toxin detection.
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Affiliation(s)
- Harmanjit Kaur
- Institute of Nano Science & Technology, Mohali, 160062, India
| | - Munish Shorie
- Institute of Nano Science & Technology, Mohali, 160062, India
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18
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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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19
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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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20
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Mühlen S, Dersch P. Treatment Strategies for Infections With Shiga Toxin-Producing Escherichia coli. Front Cell Infect Microbiol 2020; 10:169. [PMID: 32435624 PMCID: PMC7218068 DOI: 10.3389/fcimb.2020.00169] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/31/2020] [Indexed: 01/07/2023] Open
Abstract
Infections with Shiga toxin-producing Escherichia coli (STEC) cause outbreaks of severe diarrheal disease in children and the elderly around the world. The severe complications associated with toxin production and release range from bloody diarrhea and hemorrhagic colitis to hemolytic-uremic syndrome, kidney failure, and neurological issues. As the use of antibiotics for treatment of the infection has long been controversial due to reports that antibiotics may increase the production of Shiga toxin, the recommended therapy today is mainly supportive. In recent years, a variety of alternative treatment approaches such as monoclonal antibodies or antisera directed against Shiga toxin, toxin receptor analogs, and several vaccination strategies have been developed and evaluated in vitro and in animal models. A few strategies have progressed to the clinical trial phase. Here, we review the current understanding of and the progress made in the development of treatment options against STEC infections and discuss their potential.
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Affiliation(s)
- Sabrina Mühlen
- Institute for Infectiology, University of Münster, Münster, Germany.,German Center for Infection Research (DZIF), Associated Site University of Münster, Münster, Germany
| | - Petra Dersch
- Institute for Infectiology, University of Münster, Münster, Germany.,German Center for Infection Research (DZIF), Associated Site University of Münster, Münster, Germany
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21
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Berdasco C, Duhalde Vega M, Rosato-Siri MV, Goldstein J. Environmental Cues Modulate Microglial Cell Behavior Upon Shiga Toxin 2 From Enterohemorrhagic Escherichia coli Exposure. Front Cell Infect Microbiol 2020; 9:442. [PMID: 31970091 PMCID: PMC6960108 DOI: 10.3389/fcimb.2019.00442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 12/09/2019] [Indexed: 12/18/2022] Open
Abstract
Shiga toxin (Stx) produced by enterohemorrhagic E. coli produces hemolytic uremic syndrome and encephalopathies in patients, which can lead to either reversible or permanent neurological abnormalities, or even fatal cases depending on the degree of intoxication. It has been observed that the inflammatory component plays a decisive role in the severity of the disease. Therefore, the objective of this work was to evaluate the behavior of microglial cell primary cultures upon Stx2 exposure and heat shock or lipopolysaccharide challenges, as cues which modulate cellular environments, mimicking fever and inflammation states, respectively. In these contexts, activated microglial cells incorporated Stx2, increased their metabolism, phagocytic capacity, and pro-inflammatory profile. Stx2 uptake was associated to receptor globotriaosylceramide (Gb3)-pathway. Gb3 had three clearly distinguishable distribution patterns which varied according to different contexts. In addition, toxin uptake exhibited both a Gb3-dependent and a Gb3-independent binding depending on those contexts. Altogether, these results suggest a fundamental role for microglial cells in pro-inflammatory processes in encephalopathies due to Stx2 intoxication and highlight the impact of environmental cues.
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Affiliation(s)
- Clara Berdasco
- Laboratorio de Neurofisiopatología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Medicina, Instituto de Fisiología y Biofísica "Houssay", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Maite Duhalde Vega
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - María Victoria Rosato-Siri
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - Jorge Goldstein
- Laboratorio de Neurofisiopatología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Medicina, Instituto de Fisiología y Biofísica "Houssay", Universidad de Buenos Aires, Buenos Aires, Argentina
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22
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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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Kunz TC, Kozjak-Pavlovic V. Diverse Facets of Sphingolipid Involvement in Bacterial Infections. Front Cell Dev Biol 2019; 7:203. [PMID: 31608278 PMCID: PMC6761390 DOI: 10.3389/fcell.2019.00203] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 09/05/2019] [Indexed: 12/28/2022] Open
Abstract
Sphingolipids are constituents of the cell membrane that perform various tasks as structural elements and signaling molecules, in addition to regulating many important cellular processes, such as apoptosis and autophagy. In recent years, it has become increasingly clear that sphingolipids and sphingolipid signaling play a vital role in infection processes. In many cases the attachment and uptake of pathogenic bacteria, as well as bacterial development and survival within the host cell depend on sphingolipids. In addition, sphingolipids can serve as antimicrobials, inhibiting bacterial growth and formation of biofilms. This review will give an overview of our current information about these various aspects of sphingolipid involvement in bacterial infections.
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Affiliation(s)
| | - Vera Kozjak-Pavlovic
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
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24
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Vinh PT, Shinohara Y, Yamada A, Duc HM, Nakayama M, Ozawa T, Sato J, Masuda Y, Honjoh KI, Miyamoto T. Baicalein Inhibits Stx1 and 2 of EHE: Effects of Baicalein on the Cytotoxicity, Production, and Secretion of Shiga Toxins of Enterohaemorrhagic Escherichia coli. Toxins (Basel) 2019; 11:toxins11090505. [PMID: 31470657 PMCID: PMC6784239 DOI: 10.3390/toxins11090505] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/25/2019] [Accepted: 08/27/2019] [Indexed: 12/14/2022] Open
Abstract
Shiga toxin-producing enterohaemorrhagic Escherichia coli (EHEC) O157:H7 is an important foodborne pathogen. Baicalein (5,6,7-trihydroxylflavone), a flavone isolated from the roots of Scutellaria baicalensis, is considered as a potential antibacterial agent to control foodborne pathogens. Among seven compounds selected by in silico screening of the natural compound database, baicalein inhibited the cytotoxicity of both Shiga toxins 1 and 2 (Stx1 and Stx2) against Vero cells after pretreatment at 0.13 mmol/L. In addition, baicalein reduced the susceptibility of Vero cells to both Stx1 and Stx2. Real-time qPCR showed that baicalein increased transcription of stx1 but not of stx2. However, baicalein had no effects on production or secretion of Stx1 or Stx2. Docking models suggested that baicalein formed a stable structure with StxB pentamer with low intramolecular energy. The results demonstrate that inhibitory activity of baicalein against the cytotoxicity of both Stx1 and Stx2 might be due to of the formation of a binding structure inside the pocket of the Stx1B and Stx2B pentamers.
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Affiliation(s)
- Pham Thi Vinh
- Division of Food Science & Biotechnology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Yui Shinohara
- Division of Food Science & Biotechnology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Akifumi Yamada
- Division of Food Science & Biotechnology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hoang Minh Duc
- Division of Food Science & Biotechnology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Motokazu Nakayama
- Global R&D-Safty Science, Kao Corporation, 2606, Akabane, Ichikai-machi, Haga-gun, Tochigi 321-3497, Japan
| | - Tadahiro Ozawa
- Bioscience Research, Kao Corporation, 2606, Akabane, Ichikai-machi, Haga-gun, Tochigi 321-3497, Japan
| | - Jun Sato
- Global R&D-Safty Science, Kao Corporation, 2606, Akabane, Ichikai-machi, Haga-gun, Tochigi 321-3497, Japan
| | - Yoshimitsu Masuda
- Division of Food Science & Biotechnology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Ken-Ichi Honjoh
- Division of Food Science & Biotechnology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Takahisa Miyamoto
- Division of Food Science & Biotechnology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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25
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Pohlentz G, Steil D, Rubin D, Mellmann A, Karch H, Müthing J. Pectin-derived neoglycolipids: Tools for differentiation of Shiga toxin subtypes and inhibitors of Shiga toxin-mediated cellular injury. Carbohydr Polym 2019; 212:323-333. [DOI: 10.1016/j.carbpol.2019.02.039] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 02/04/2019] [Accepted: 02/12/2019] [Indexed: 01/14/2023]
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26
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Stromberg ZR, Redweik GAJ, Mellata M. Detection, Prevalence, and Pathogenicity of Non-O157 Shiga Toxin-Producing Escherichia coli from Cattle Hides and Carcasses. Foodborne Pathog Dis 2019; 15:119-131. [PMID: 29638166 DOI: 10.1089/fpd.2017.2401] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Cattle are a major reservoir for Shiga toxin-producing Escherichia coli (STEC) and harbor these bacteria in the intestinal tract. The prevalence, concentration, and STEC serogroup isolated in cattle varies between individuals. Hide removal at slaughter serves as a major point of carcass contamination and ultimately beef products. Certain STEC serogroups, such as O26, O45, O103, O111, O121, O145, and O157, containing the intestinal adherence factor intimin, pose a large economic burden to food producers because of testing and recalls. Human infection with STEC can cause illnesses ranging from diarrhea to hemorrhagic colitis and hemolytic uremic syndrome, and is commonly acquired through ingestion of contaminated foods, often beef products. Previously, most studies focused on O157 STEC, but there is growing recognition of the importance of non-O157 STEC serogroups. This review summarizes detection methods, prevalence, and methods for prediction of pathogenicity of non-O157 STEC from cattle hides and carcasses. A synthesis of procedures is outlined for general non-O157 STEC and targeted detection of specific STEC serogroups. Standardization of sample collection and processing procedures would allow for more robust comparisons among studies. Presence of non-O157 STEC isolated from cattle hides and carcasses and specific factors, such as point of sample collection and season, are summarized. Also, factors that might influence STEC survival on these surfaces, such as the microbial population on hides and microbial adherence genes, are raised as topics for future investigation. Finally, this review gives an overview on studies that have used genetic and cell-based methods to identify specific phenotypes of non-O157 STEC strains isolated from cattle to assess their risk to human health.
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Affiliation(s)
- Zachary R Stromberg
- Department of Food Science and Human Nutrition, Iowa State University , Ames, Iowa
| | - Graham A J Redweik
- Department of Food Science and Human Nutrition, Iowa State University , Ames, Iowa
| | - Melha Mellata
- Department of Food Science and Human Nutrition, Iowa State University , Ames, Iowa
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Luz D, Amaral MM, Sacerdoti F, Bernal AM, Quintilio W, Moro AM, Palermo MS, Ibarra C, Piazza RMF. Human Recombinant Fab Fragment Neutralizes Shiga Toxin Type 2 Cytotoxic Effects in vitro and in vivo. Toxins (Basel) 2018; 10:E508. [PMID: 30513821 PMCID: PMC6315604 DOI: 10.3390/toxins10120508] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/24/2018] [Accepted: 11/28/2018] [Indexed: 12/13/2022] Open
Abstract
Shiga toxin (Stx) producing Escherichia coli (STEC) is responsible for causing hemolytic uremic syndrome (HUS), a life-threatening thrombotic microangiopathy characterized by thrombocytopenia, hemolytic anemia, and acute renal failure after bacterially induced hemorrhagic diarrhea. Until now, there has been neither an effective treatment nor method of prevention for the deleterious effects caused by Stx intoxication. Antibodies are well recognized as affinity components of therapeutic drugs; thus, a previously obtained recombinant human FabC11:Stx2 fragment was used to neutralize Stx2 in vitro in a Vero cell viability assay. Herein, we demonstrated that this fragment neutralized, in a dose-dependent manner, the cytotoxic effects of Stx2 on human glomerular endothelial cells, on human proximal tubular epithelial cells, and prevented the morphological alterations induced by Stx2. FabC11:Stx2 protected mice from a lethal dose of Stx2 by toxin-antibody pre-incubation. Altogether, our results show the ability of a new encouraging molecule to prevent Stx-intoxication symptoms during STEC infection.
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Affiliation(s)
- Daniela Luz
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo 05503900, Brasil.
| | - Maria Marta Amaral
- 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 C1121, Argentina.
| | - Flavia Sacerdoti
- 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 C1121, Argentina.
| | - Alan Mauro Bernal
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, (IMEX)-CONICET-Academia Nacional de Medicina, Buenos Aires C1425, Argentina.
| | - Wagner Quintilio
- Laboratório de Biofármacos em Células Animais, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Ana Maria Moro
- Laboratório de Biofármacos em Células Animais, Instituto Butantan, São Paulo, SP 05503-900, Brazil.
| | - Marina Sandra Palermo
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, (IMEX)-CONICET-Academia Nacional de Medicina, Buenos Aires C1425, Argentina.
| | - 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 C1121, Argentina.
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28
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Legros N, Pohlentz G, Steil D, Müthing J. Shiga toxin-glycosphingolipid interaction: Status quo of research with focus on primary human brain and kidney endothelial cells. Int J Med Microbiol 2018; 308:1073-1084. [PMID: 30224239 DOI: 10.1016/j.ijmm.2018.09.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 08/28/2018] [Accepted: 09/06/2018] [Indexed: 12/21/2022] Open
Abstract
Shiga toxin (Stx)-mediated injury of the kidneys and the brain represent the major extraintestinal complications in humans upon infection by enterohemorrhagic Escherichia coli (EHEC). Damage of renal and cerebral endothelial cells is the key event in the pathogenesis of the life-threatening hemolytic uremic syndrome (HUS). Stxs are AB5 toxins and the B-pentamers of the two clinically important Stx subtypes Stx1a and Stx2a preferentially bind to the glycosphingolipid globotriaosylceramide (Gb3Cer, Galα4Galβ4Glcβ1Cer) and to less extent to globotetraosylceramide (Gb4Cer, GalNAcβ3Galα4Galβ4Glcβ1), which are expected to reside in lipid rafts in the plasma membrane of the human endothelium. This review summarizes the current knowledge on the Stx glycosphingolipid receptors and their lipid membrane ensemble in primary human brain microvascular endothelial cells (pHBMECs) and primary human renal glomerular endothelial cells (pHRGECs). Increasing knowledge on the precise initial molecular mechanisms by which Stxs interact with cellular targets will help to develop specific therapeutics and/or preventive measures to combat EHEC-caused diseases.
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Affiliation(s)
- Nadine Legros
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany
| | | | - Daniel Steil
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany
| | - Johannes Müthing
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany; Interdisciplinary Center for Clinical Research (IZKF), University of Münster, D-48149 Münster, Germany.
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29
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Abstract
Enterohemorrhagic Escherichia coli (EHEC) has two critical virulence factors—a type III secretion system (T3SS) and Shiga toxins (Stxs)—that are required for the pathogen to colonize the intestine and cause diarrheal disease. Here, we carried out a genome-wide CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats with Cas9) loss-of-function screen to identify host loci that facilitate EHEC infection of intestinal epithelial cells. Many of the guide RNAs identified targeted loci known to be associated with sphingolipid biosynthesis, particularly for production of globotriaosylceramide (Gb3), the Stx receptor. Two loci (TM9SF2 and LAPTM4A) with largely unknown functions were also targeted. Mutations in these loci not only rescued cells from Stx-mediated cell death, but also prevented cytotoxicity associated with the EHEC T3SS. These mutations interfered with early events associated with T3SS and Stx pathogenicity, markedly reducing entry of T3SS effectors into host cells and binding of Stx. The convergence of Stx and T3SS onto overlapping host targets provides guidance for design of new host-directed therapeutic agents to counter EHEC infection. Enterohemorrhagic Escherichia coli (EHEC) has two critical virulence factors—a type III secretion system (T3SS) and Shiga toxins (Stxs)—that are required for colonizing the intestine and causing diarrheal disease. We screened a genome-wide collection of CRISPR mutants derived from intestinal epithelial cells and identified mutants with enhanced survival following EHEC infection. Many had mutations that disrupted synthesis of a subset of lipids (sphingolipids) that includes the Stx receptor globotriaosylceramide (Gb3) and hence protect against Stx intoxication. Unexpectedly, we found that sphingolipids also mediate early events associated with T3SS pathogenicity. Since antibiotics are contraindicated for the treatment of EHEC, therapeutics targeting sphingolipid biosynthesis are a promising alternative, as they could provide protection against both of the pathogen’s key virulence factors.
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30
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Legros N, Pohlentz G, Steil D, Kouzel IU, Liashkovich I, Mellmann A, Karch H, Müthing J. Membrane assembly of Shiga toxin glycosphingolipid receptors and toxin refractiveness of MDCK II epithelial cells. J Lipid Res 2018; 59:1383-1401. [PMID: 29866658 DOI: 10.1194/jlr.m083048] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 05/22/2018] [Indexed: 12/16/2022] Open
Abstract
Shiga toxins (Stxs) are the major virulence factors of Stx-producing Escherichia coli (STEC), which cause hemorrhagic colitis and severe extraintestinal complications due to injury of renal endothelial cells, resulting in kidney failure. Since kidney epithelial cells are suggested additional targets for Stxs, we analyzed Madin-Darby canine kidney (MDCK) II epithelial cells for presence of Stx-binding glycosphingolipids (GSLs), determined their distribution to detergent-resistant membranes (DRMs), and ascertained the lipid composition of DRM and non-DRM preparations. Globotriaosylceramide and globotetraosylceramide, known as receptors for Stx1a, Stx2a, and Stx2e, and Forssman GSL as a specific receptor for Stx2e, were found to cooccur with SM and cholesterol in DRMs of MDCK II cells, which was shown using TLC overlay assay detection combined with mass spectrometry. The various lipoforms of GSLs were found to mainly harbor ceramide moieties composed of sphingosine (d18:1) and C24:1/C24:0 or C16:0 FA. The cells were highly refractory toward Stx1a, Stx2a, and Stx2e, most likely due to the absence of Stx-binding GSLs in the apical plasma membrane determined by immunofluorescence confocal laser scanning microscopy. The results suggest that the cellular content of Stx receptor GSLs and their biochemical detection in DRM preparations alone are inadequate to predict cellular sensitivity toward Stxs.
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Affiliation(s)
- Nadine Legros
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany
| | | | - Daniel Steil
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany
| | - Ivan U Kouzel
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.,Interdisciplinary Center for Clinical Research, University of Münster, D-48149 Münster, Germany
| | - Ivan Liashkovich
- Institute of Physiology II, University of Münster, D-48149 Münster, Germany
| | - Alexander Mellmann
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.,Interdisciplinary Center for Clinical Research, University of Münster, D-48149 Münster, Germany
| | - Helge Karch
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany.,Interdisciplinary Center for Clinical Research, University of Münster, D-48149 Münster, Germany
| | - Johannes Müthing
- Institute for Hygiene, University of Münster, D-48149 Münster, Germany .,Interdisciplinary Center for Clinical Research, University of Münster, D-48149 Münster, Germany
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31
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Immunization of pregnant cows with Shiga toxin-2 induces high levels of specific colostral antibodies and lactoferrin able to neutralize E. coli O157:H7 pathogenicity. Vaccine 2018; 36:1728-1735. [DOI: 10.1016/j.vaccine.2018.02.060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 01/30/2018] [Accepted: 02/15/2018] [Indexed: 12/24/2022]
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Bernedo-Navarro RA, Romão E, Yano T, Pinto J, De Greve H, Sterckx YGJ, Muyldermans S. Structural Basis for the Specific Neutralization of Stx2a with a Camelid Single Domain Antibody Fragment. Toxins (Basel) 2018; 10:toxins10030108. [PMID: 29494518 PMCID: PMC5869396 DOI: 10.3390/toxins10030108] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 02/08/2018] [Accepted: 02/26/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Shiga toxin-producing Escherichia coli (STEC) are a subset of pathogens leading to illnesses such as diarrhea, hemolytic uremic syndrome and even death. The Shiga toxins are the main virulence factors and divided in two groups: Stx1 and Stx2, of which the latter is more frequently associated with severe pathologies in humans. RESULTS An immune library of nanobodies (Nbs) was constructed after immunizing an alpaca with recombinant Shiga toxin-2a B subunit (rStx2aB), to retrieve multiple rStx2aB-specific Nbs. The specificity of five Nbs towards rStx2aB was confirmed in ELISA and Western blot. Nb113 had the highest affinity (9.6 nM) and its bivalent construct exhibited a 100-fold higher functional affinity. The structure of the Nb113 in complex with rStx2aB was determined via X-ray crystallography. The crystal structure of the Nb113-rStx2aB complex revealed that five copies of Nb113 bind to the rStx2aB pentamer and that the Nb113 epitope overlaps with the Gb3 binding site, thereby providing a structural basis for the neutralization of Stx2a by Nb113 that was observed on Vero cells. Finally, the tandem-repeated, bivalent Nb113₂ exhibits a higher toxin neutralization capacity compared to monovalent Nb113. CONCLUSIONS The Nb of highest affinity for rStx2aB is also the best Stx2a and Stx2c toxin neutralizing Nb, especially in a bivalent format. This lead Nb neutralizes Stx2a by competing for the Gb3 receptor. The fusion of the bivalent Nb113₂ with a serum albumin specific Nb is expected to combine high toxin neutralization potential with prolonged blood circulation.
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Affiliation(s)
- Robert Alvin Bernedo-Navarro
- Laboratory of Bacterial Genetics, Institute of Biology, University of Campinas (UNICAMP), São Paulo 13083-862, Brazil.
| | - Ema Romão
- Cellular and Molecular Immunology, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
| | - Tomomasa Yano
- Laboratory of Bacterial Genetics, Institute of Biology, University of Campinas (UNICAMP), São Paulo 13083-862, Brazil.
| | - Joar Pinto
- Cellular and Molecular Immunology, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
| | - Henri De Greve
- Structural Molecular Microbiology, Vlaams Instituut voor Biotechnologie (VIB), 1050 Brussels, Belgium.
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
| | - Yann G-J Sterckx
- Cellular and Molecular Immunology, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
| | - Serge Muyldermans
- Cellular and Molecular Immunology, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
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Yahiro K, Nagasawa S, Ichimura K, Takeuchi H, Ogura K, Tsutsuki H, Shimizu T, Iyoda S, Ohnishi M, Iwase H, Moss J, Noda M. Mechanism of inhibition of Shiga-toxigenic Escherichia coli SubAB cytotoxicity by steroids and diacylglycerol analogues. Cell Death Discov 2018. [PMID: 29531819 PMCID: PMC5841432 DOI: 10.1038/s41420-017-0007-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Shiga toxigenic Escherichia coli (STEC) are responsible for a worldwide foodborne disease, which is characterized by severe bloody diarrhea and hemolytic uremic syndrome (HUS). Subtilase cytotoxin (SubAB) is a novel AB5 toxin, which is produced by Locus for Enterocyte Effacement (LEE)-negative STEC. Cleavage of the BiP protein by SubAB induces endoplasmic reticulum (ER) stress, followed by induction of cytotoxicity in vitro or lethal severe hemorrhagic inflammation in mice. Here we found that steroids and diacylglycerol (DAG) analogues (e.g., bryostatin 1, Ingenol-3-angelate) inhibited SubAB cytotoxicity. In addition, steroid-induced Bcl-xL expression was a key step in the inhibition of SubAB cytotoxicity. Bcl-xL knockdown increased SubAB-induced apoptosis in steroid-treated HeLa cells, whereas SubAB-induced cytotoxicity was suppressed in Bcl-xL overexpressing cells. In contrast, DAG analogues suppressed SubAB activity independent of Bcl-xL expression at early time points. Addition of Shiga toxin 2 (Stx2) with SubAB to cells enhanced cytotoxicity even in the presence of steroids. In contrast, DAG analogues suppressed cytotoxicity seen in the presence of both toxins. Here, we show the mechanism by which steroids and DAG analogues protect cells against SubAB toxin produced by LEE-negative STEC.
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Affiliation(s)
- Kinnosuke Yahiro
- 1Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Sayaka Nagasawa
- 2Department of Legal Medicine, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Kimitoshi Ichimura
- 1Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Hiroki Takeuchi
- 1Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Kohei Ogura
- 3Pathogenic Microbe Laboratory, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan
| | - Hiroyasu Tsutsuki
- 4Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Takeshi Shimizu
- 1Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Sunao Iyoda
- 5Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Makoto Ohnishi
- 5Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Hirotaro Iwase
- 2Department of Legal Medicine, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Joel Moss
- 6Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD USA
| | - Masatoshi Noda
- 1Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba, Japan
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Luginbuehl V, Meier N, Kovar K, Rohrer J. Intracellular drug delivery: Potential usefulness of engineered Shiga toxin subunit B for targeted cancer therapy. Biotechnol Adv 2018; 36:613-623. [PMID: 29432805 DOI: 10.1016/j.biotechadv.2018.02.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 01/30/2018] [Accepted: 02/05/2018] [Indexed: 12/15/2022]
Abstract
A treasure trove of intracellular cancer drug targets remains hidden behind cell membranes. However, engineered pathogen-derived toxins such as Shiga toxins can deliver small or macromolecular drugs to specific intracellular organelles. After binding to ganglioglobotriaosylceramide (Gb3, CD77), the non-toxic subunit B (StxB) of the Shiga-holotoxin is endocytosed and delivers its payload by a unique retrograde trafficking pathway via the endoplasmic reticulum to the cytosol. This review provides an overview of biomedical applications of StxB-based drug delivery systems in targeted cancer diagnosis and therapy. Biotechnological production of the Stx-material is discussed from the perspective of developing efficacious and safe therapeutics.
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Affiliation(s)
- Vera Luginbuehl
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Nicolas Meier
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Karin Kovar
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Jack Rohrer
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland.
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Shiga Toxin Glycosphingolipid Receptors in Human Caco-2 and HCT-8 Colon Epithelial Cell Lines. Toxins (Basel) 2017; 9:toxins9110338. [PMID: 29068380 PMCID: PMC5705953 DOI: 10.3390/toxins9110338] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 10/11/2017] [Accepted: 10/19/2017] [Indexed: 12/21/2022] Open
Abstract
Shiga toxins (Stxs) released by enterohemorrhagic Escherichia coli (EHEC) into the human colon are the causative agents for fatal outcome of EHEC infections. Colon epithelial Caco-2 and HCT-8 cells are widely used for investigating Stx-mediated intestinal cytotoxicity. Only limited data are available regarding precise structures of their Stx receptor glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer) and globotetraosylceramide (Gb4Cer), and lipid raft association. In this study we identified Gb3Cer and Gb4Cer lipoforms of serum-free cultivated Caco-2 and HCT-8 cells, chiefly harboring ceramide moieties composed of sphingosine (d18:1) and C16:0, C22:0 or C24:0/C24:1 fatty acid. The most significant difference between the two cell lines was the prevalence of Gb3Cer with C16 fatty acid in HCT-8 and Gb4Cer with C22–C24 fatty acids in Caco-2 cells. Lipid compositional analysis of detergent-resistant membranes (DRMs), which were used as lipid raft-equivalents, indicated slightly higher relative content of Stx receptor Gb3Cer in DRMs of HCT-8 cells when compared to Caco-2 cells. Cytotoxicity assays revealed substantial sensitivity towards Stx2a for both cell lines, evidencing little higher susceptibility of Caco-2 cells versus HCT-8 cells. Collectively, Caco-2 and HCT-8 cells express a plethora of different receptor lipoforms and are susceptible towards Stx2a exhibiting somewhat lower sensitivity when compared to Vero cells.
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Selyunin AS, Iles LR, Bartholomeusz G, Mukhopadhyay S. Genome-wide siRNA screen identifies UNC50 as a regulator of Shiga toxin 2 trafficking. J Cell Biol 2017; 216:3249-3262. [PMID: 28883040 PMCID: PMC5626549 DOI: 10.1083/jcb.201704015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 07/06/2017] [Accepted: 08/02/2017] [Indexed: 12/19/2022] Open
Abstract
Toxins produced by Shigella bacteria undergo endosome-to-Golgi retrograde trafficking to evade degradation in the lysosome and reach the cytosol. Selyunin et al. performed a genome-wide siRNA screen and identify host factors required for the transport and toxicity of Shiga toxins. Shiga toxins 1 and 2 (STx1 and STx2) undergo retrograde trafficking to reach the cytosol. Early endosome-to-Golgi transport allows the toxins to evade degradation in lysosomes. Targeting this trafficking step has therapeutic promise, but the mechanism of trafficking for the more potent toxin STx2 is unclear. To identify host factors required for early endosome-to-Golgi trafficking of STx2, we performed a viability-based genome-wide siRNA screen in HeLa cells. 564, 535, and 196 genes were found to be required for toxicity induced by STx1 only, STx2 only, and both toxins, respectively. We focused on validating endosome/Golgi-localized hits specific for STx2 and found that depletion of UNC50 blocked early endosome-to-Golgi trafficking and induced lysosomal degradation of STx2. UNC50 acted by recruiting GBF1, an ADP ribosylation factor–guanine nucleotide exchange factor (ARF-GEF), to the Golgi. These results provide new information about STx2 trafficking mechanisms and may advance efforts to generate therapeutically viable toxin-trafficking inhibitors.
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Affiliation(s)
- Andrey S Selyunin
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX.,Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX.,Institute for Neuroscience, The University of Texas at Austin, Austin, TX
| | - Lakesla R Iles
- Department of Experimental Therapeutics, MD Anderson Cancer Center, Houston, TX
| | | | - Somshuvra Mukhopadhyay
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX .,Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX.,Institute for Neuroscience, The University of Texas at Austin, Austin, TX
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Cheng K, Sloan A, Li X, Armstrong GD, Wang G. Mass spectrometry-based Shiga toxin identification: An optimized approach. J Proteomics 2017; 180:36-40. [PMID: 28602982 DOI: 10.1016/j.jprot.2017.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 05/25/2017] [Accepted: 06/02/2017] [Indexed: 10/19/2022]
Abstract
Toxin expression is a key factor in Shiga toxin (Stx)-producing E. coli, a common pathogen involved in foodborne disease outbreaks. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) based approach has been used in this study to identify commonly reported E. coli toxins, with a focus on Shiga toxins (Stxs). Different sample preparation methods using variable culture conditions and concentrations of mitomycin C (MMC), a common antibiotic/chemotherapy agent capable of stimulating Stx production, were first tested on reference strains EDL933 and 90-2380 by LC-MS/MS detection of tryptic digests of receptor-analogue affinity binding enriched Stx preparations from culture supernatants and lysates. A curated E. coli protein toxin database was also used for faster and more straightforward toxin identification. With eight more genetically confirmed E. coli strains examined to verify the method, this preliminary study indicates that receptor-analogue based affinity enrichment on cell lysate or supernatant is a sensitive and accurate method for Stx identification. BIOLOGICAL SIGNIFICANCE The existence of Stx is very important for identifying Stx-producing E. coli and implementing a clinical treatment regime. This study demonstrates for the first time that using a curated E. coli toxin database, together with receptor-analogue-based affinity enrichment of Stxs after MMC treatment of E. coli, is an easy and appropriate approach for fast and accurate Stx identification through LC-MS/MS.
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Affiliation(s)
- Keding Cheng
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada; Department of Human Anatomy and Cell Sciences, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
| | - Angela Sloan
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Xingle Li
- Henan Center for Disease Control, Henan, PR China
| | - Glen D Armstrong
- Department of Microbiology, Immunology & Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Gehua Wang
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
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Barth H. An Introduction to the Toxins Special Issue on "Novel Pharmacological Inhibitors for Bacterial Protein Toxins". Toxins (Basel) 2017; 9:toxins9050160. [PMID: 28492500 PMCID: PMC5450708 DOI: 10.3390/toxins9050160] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 05/09/2017] [Accepted: 05/10/2017] [Indexed: 12/24/2022] Open
Affiliation(s)
- Holger Barth
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
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