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Tam CC, Du WX, Wang Y, Flannery AR, He X. Rapid and Sensitive Detection of Shiga Toxin-Producing Escherichia coli (STEC) from Food Matrices Using the CANARY Biosensor Assay. Toxins (Basel) 2024; 16:325. [PMID: 39057965 PMCID: PMC11281303 DOI: 10.3390/toxins16070325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 07/15/2024] [Accepted: 07/19/2024] [Indexed: 07/28/2024] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) causes a wide spectrum of diseases including hemorrhagic colitis and hemolytic uremic syndrome (HUS). Previously, we developed a rapid, sensitive, and potentially portable assay that identified STEC by detecting Shiga toxin (Stx) using a B-cell based biosensor platform. We applied this assay to detect Stx2 present in food samples that have been implicated in previous STEC foodborne outbreaks (milk, lettuce, and beef). The STEC enrichment medium, modified Tryptone Soy Broth (mTSB), inhibited the biosensor assay, but dilution with the assay buffer relieved this effect. Results with Stx2a toxoid-spiked food samples indicated an estimated limit of detection (LOD) of ≈4 ng/mL. When this assay was applied to food samples inoculated with STEC, it was able to detect 0.4 CFU/g or 0.4 CFU/mL of STEC at 16 h post incubation (hpi) in an enrichment medium containing mitomycin C. Importantly, this assay was even able to detect STEC strains that were high expressors of Stx2 at 8 hpi. These results indicate that the STEC CANARY biosensor assay is a rapid and sensitive assay applicable for detection of STEC contamination in food with minimal sample processing that can complement the current Food Safety Inspection Service (US) methodologies for STEC.
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Affiliation(s)
- Christina C. Tam
- Foodborne Toxin Detection and Prevention Research Unit, Western Regional Research Center, Agricultural Research Services, United States Department of Agriculture, 800 Buchanan Street, Albany, CA 94710, USA; (C.C.T.); (W.-X.D.)
| | - Wen-Xian Du
- Foodborne Toxin Detection and Prevention Research Unit, Western Regional Research Center, Agricultural Research Services, United States Department of Agriculture, 800 Buchanan Street, Albany, CA 94710, USA; (C.C.T.); (W.-X.D.)
| | - Yangyang Wang
- Smiths Detection, 2202 Lakeside Blvd, Edgewood, MD 21040, USA; (Y.W.); (A.R.F.)
| | - Andrew R. Flannery
- Smiths Detection, 2202 Lakeside Blvd, Edgewood, MD 21040, USA; (Y.W.); (A.R.F.)
| | - Xiaohua He
- Foodborne Toxin Detection and Prevention Research Unit, Western Regional Research Center, Agricultural Research Services, United States Department of Agriculture, 800 Buchanan Street, Albany, CA 94710, USA; (C.C.T.); (W.-X.D.)
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2
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He N, Depta L, Rossetti C, Caramelle L, Cigler M, Bryce-Rogers HP, Michon M, Rafn Dan O, Hoock J, Barbier J, Gillet D, Forrester A, Winter GE, Laraia L. Inhibition of OSBP blocks retrograde trafficking by inducing partial Golgi degradation. Nat Chem Biol 2024:10.1038/s41589-024-01653-x. [PMID: 38907112 DOI: 10.1038/s41589-024-01653-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/16/2024] [Indexed: 06/23/2024]
Abstract
Sterol-binding proteins are important regulators of lipid homeostasis and membrane integrity; however, the discovery of selective modulators can be challenging due to structural similarities in the sterol-binding domains. We report the discovery of potent and selective inhibitors of oxysterol-binding protein (OSBP), which we term oxybipins. Sterol-containing chemical chimeras aimed at identifying new sterol-binding proteins by targeted degradation, led to a significant reduction in levels of Golgi-associated proteins. The degradation occurred in lysosomes, concomitant with changes in protein glycosylation, indicating that the degradation of Golgi proteins was a downstream effect. By establishing a sterol transport protein biophysical assay panel, we discovered that the oxybipins potently inhibited OSBP, resulting in blockage of retrograde trafficking and attenuating Shiga toxin toxicity. As the oxybipins do not target other sterol transporters and only stabilized OSBP in intact cells, we advocate their use as tools to study OSBP function and therapeutic relevance.
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Affiliation(s)
- Nianzhe He
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Laura Depta
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Cecilia Rossetti
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Lucie Caramelle
- Unit of Research of Biochemistry and Cell Biology (URBC), Namur Research Institute for Life Sciences (NARILIS), Université de Namur ASBL, Namur, Belgium
| | - Marko Cigler
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | | | - Marine Michon
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, Gif-sur-Yvette, France
| | - Oliver Rafn Dan
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Joseph Hoock
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Julien Barbier
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, Gif-sur-Yvette, France
| | - Daniel Gillet
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, Gif-sur-Yvette, France
| | - Alison Forrester
- Unit of Research of Biochemistry and Cell Biology (URBC), Namur Research Institute for Life Sciences (NARILIS), Université de Namur ASBL, Namur, Belgium
| | - Georg E Winter
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Luca Laraia
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark.
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3
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MacNair CR, Rutherford ST, Tan MW. Alternative therapeutic strategies to treat antibiotic-resistant pathogens. Nat Rev Microbiol 2024; 22:262-275. [PMID: 38082064 DOI: 10.1038/s41579-023-00993-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2023] [Indexed: 04/19/2024]
Abstract
Resistance threatens to render antibiotics - which are essential for modern medicine - ineffective, thus posing a threat to human health. The discovery of novel classes of antibiotics able to overcome resistance has been stalled for decades, with the developmental pipeline relying almost entirely on variations of existing chemical scaffolds. Unfortunately, this approach has been unable to keep pace with resistance evolution, necessitating new therapeutic strategies. In this Review, we highlight recent efforts to discover non-traditional antimicrobials, specifically describing the advantages and limitations of antimicrobial peptides and macrocycles, antibodies, bacteriophages and antisense oligonucleotides. These approaches have the potential to stem the tide of resistance by expanding the physicochemical property space and target spectrum occupied by currently approved antibiotics.
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Affiliation(s)
- Craig R MacNair
- Department of Infectious Diseases, Genentech Inc., South San Francisco, CA, USA
| | - Steven T Rutherford
- Department of Infectious Diseases, Genentech Inc., South San Francisco, CA, USA
| | - Man-Wah Tan
- Department of Infectious Diseases, Genentech Inc., South San Francisco, CA, USA.
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4
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Kirkland ME, Patfield S, Hughes AC, Hernlem B, He X. A novel Shiga toxin 2a neutralizing antibody therapeutic with low immunogenicity and high efficacy. Antimicrob Agents Chemother 2024; 68:e0059823. [PMID: 38047751 PMCID: PMC10777836 DOI: 10.1128/aac.00598-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 10/18/2023] [Indexed: 12/05/2023] Open
Abstract
Shiga toxin-producing Escherichia coli infections are difficult to treat due to the risk of antibiotic-induced stress upregulating the production of toxins, medical treatment is consequently limited to supportive care to prevent the development of hemolytic uremic syndrome (HUS). Here, we introduce a potentially therapeutic humanized mouse monoclonal antibody (Hu-mAb 2-5) targeting Stx2a, the most common Shiga toxin subtype identified from outbreaks. We demonstrate that Hu-mAb 2-5 has low immunogenicity in healthy adults ex vivo and high neutralizing efficacy in vivo, protecting mice from mortality and HUS-related tissue damage.
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Affiliation(s)
- Marina E. Kirkland
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
- U.S. Department of Energy, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA
| | - Stephanie Patfield
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
| | - Anna C. Hughes
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
| | - Bradley Hernlem
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
| | - Xiaohua He
- United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, California, USA
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Bumunang EW, Zaheer R, Stanford K, Laing C, Niu D, Guan LL, Chui L, Tarr GAM, McAllister TA. Genomic Analysis of Shiga Toxin-Producing E. coli O157 Cattle and Clinical Isolates from Alberta, Canada. Toxins (Basel) 2022; 14:603. [PMID: 36136541 PMCID: PMC9505746 DOI: 10.3390/toxins14090603] [Citation(s) in RCA: 2] [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: 07/27/2022] [Revised: 08/24/2022] [Accepted: 08/24/2022] [Indexed: 12/02/2022] Open
Abstract
Shiga toxin (stx) is the principal virulence factor of the foodborne pathogen, Shiga toxin-producing Escherichia coli (STEC) O157:H7 and is associated with various lambdoid bacterio (phages). A comparative genomic analysis was performed on STEC O157 isolates from cattle (n = 125) and clinical (n = 127) samples to characterize virulence genes, stx-phage insertion sites and antimicrobial resistance genes that may segregate strains circulating in the same geographic region. In silico analyses revealed that O157 isolates harboured the toxin subtypes stx1a and stx2a. Most cattle (76.0%) and clinical (76.4%) isolates carried the virulence gene combination of stx1, stx2, eae and hlyA. Characterization of stx1 and stx2-carrying phages in assembled contigs revealed that they were associated with mlrA and wrbA insertion sites, respectively. In cattle isolates, mlrA and wrbA insertion sites were occupied more often (77% and 79% isolates respectively) than in clinical isolates (38% and 1.6% isolates, respectively). Profiling of antimicrobial resistance genes (ARGs) in the assembled contigs revealed that 8.8% of cattle (11/125) and 8.7% of clinical (11/127) isolates harboured ARGs. Eight antimicrobial resistance genes cassettes (ARCs) were identified in 14 isolates (cattle, n = 8 and clinical, n = 6) with streptomycin (aadA1, aadA2, ant(3'')-Ia and aph(3'')-Ib) being the most prevalent gene in ARCs. The profound disparity between the cattle and clinical strains in occupancy of the wrbA locus suggests that this trait may serve to differentiate cattle from human clinical STEC O157:H7. These findings are important for stx screening and stx-phage insertion site genotyping as well as monitoring ARGs in isolates from cattle and clinical samples.
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Affiliation(s)
- Emmanuel W. Bumunang
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Rahat Zaheer
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB T1J 4B1, Canada
| | - Kim Stanford
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K 1M4, Canada
| | - Chad Laing
- National Centre for Animal Disease Canadian Food Inspection Agency, Lethbridge, AB T1J 0P3, Canada
| | - Dongyan Niu
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Le Luo Guan
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P9, Canada
| | - Linda Chui
- Alberta Precisions Laboratory, Alberta Public Health, Edmonton, AB T6G 2J2, Canada
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2B7, Canada
| | - Gillian A. M. Tarr
- Division of Environmental Health Sciences, School of Public Health, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tim A. McAllister
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB T1J 4B1, Canada
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6
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Henrique IDM, Sacerdoti F, Ferreira RL, Henrique C, Amaral MM, Piazza RMF, Luz D. Therapeutic Antibodies Against Shiga Toxins: Trends and Perspectives. Front Cell Infect Microbiol 2022; 12:825856. [PMID: 35223548 PMCID: PMC8866733 DOI: 10.3389/fcimb.2022.825856] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/11/2022] [Indexed: 12/22/2022] Open
Abstract
Shiga toxins (Stx) are AB5-type toxins, composed of five B subunits which bind to Gb3 host cell receptors and an active A subunit, whose action on the ribosome leads to protein synthesis suppression. The two Stx types (Stx1 and Stx2) and their subtypes can be produced by Shiga toxin-producing Escherichia coli strains and some Shigella spp. These bacteria colonize the colon and induce diarrhea that may progress to hemorrhagic colitis and in the most severe cases, to hemolytic uremic syndrome, which could lead to death. Since the use of antibiotics in these infections is a topic of great controversy, the treatment remains supportive and there are no specific therapies to ameliorate the course. Therefore, there is an open window for Stx neutralization employing antibodies, which are versatile molecules. Indeed, polyclonal, monoclonal, and recombinant antibodies have been raised and tested in vitro and in vivo assays, showing differences in their neutralizing ability against deleterious effects of Stx. These molecules are in different phases of development for which we decide to present herein an updated report of these antibody molecules, their source, advantages, and disadvantages of the promising ones, as well as the challenges faced until reaching their applicability.
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Affiliation(s)
| | - 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, Argentina
| | | | - Camila Henrique
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Maria 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, Argentina
| | - Roxane Maria Fontes Piazza
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
- *Correspondence: Roxane Maria Fontes Piazza, ; Daniela Luz,
| | - Daniela Luz
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
- *Correspondence: Roxane Maria Fontes Piazza, ; Daniela Luz,
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7
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AB 5 Enterotoxin-Mediated Pathogenesis: Perspectives Gleaned from Shiga Toxins. Toxins (Basel) 2022; 14:toxins14010062. [PMID: 35051039 PMCID: PMC8779504 DOI: 10.3390/toxins14010062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/12/2022] [Accepted: 01/12/2022] [Indexed: 02/01/2023] Open
Abstract
Foodborne diseases affect an estimated 600 million people worldwide annually, with the majority of these illnesses caused by Norovirus, Vibrio, Listeria, Campylobacter, Salmonella, and Escherichia coli. To elicit infections in humans, bacterial pathogens express a combination of virulence factors and toxins. AB5 toxins are an example of such toxins that can cause various clinical manifestations, including dehydration, diarrhea, kidney damage, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Treatment of most bacterial foodborne illnesses consists of fluid replacement and antibiotics. However, antibiotics are not recommended for infections caused by Shiga toxin-producing E. coli (STEC) because of the increased risk of HUS development, although there are conflicting views and results in this regard. Lack of effective treatment strategies for STEC infections pose a public health threat during outbreaks; therefore, the debate on antibiotic use for STEC infections could be further explored, along with investigations into antibiotic alternatives. The overall goal of this review is to provide a succinct summary on the mechanisms of action and the pathogenesis of AB5 and related toxins, as expressed by bacterial foodborne pathogens, with a primary focus on Shiga toxins (Stx). The role of Stx in human STEC disease, detection methodologies, and available treatment options are also briefly discussed.
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8
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Lee K, Lee J, Lee P, Jeon BC, Song MY, Kwak S, Lee J, Kim J, Kim D, Kim JH, Tesh VL, Lee M, Park S. Inhibition of O-GlcNAcylation protects from Shiga toxin-mediated cell injury and lethality in host. EMBO Mol Med 2022; 14:e14678. [PMID: 34842355 PMCID: PMC8749473 DOI: 10.15252/emmm.202114678] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 11/08/2021] [Accepted: 11/11/2021] [Indexed: 11/09/2022] Open
Abstract
Shiga toxins (Stxs) produced by enterohemorrhagic Escherichia coli (EHEC) are the major virulence factors responsible for hemorrhagic colitis, which can lead to life-threatening systemic complications including acute renal failure (hemolytic uremic syndrome) and neuropathy. Here, we report that O-GlcNAcylation, a type of post-translational modification, was acutely increased upon induction of endoplasmic reticulum (ER) stress in host cells by Stxs. Suppression of the abnormal Stx-mediated increase in O-GlcNAcylation effectively inhibited apoptotic and inflammatory responses in Stx-susceptible cells. The protective effect of O-GlcNAc inhibition for Stx-mediated pathogenic responses was also verified using three-dimensional (3D)-cultured spheroids or organoids mimicking the human kidney. Treatment with an O-GlcNAcylation inhibitor remarkably improved the major disease symptoms and survival rate for mice intraperitoneally injected with a lethal dose of Stx. In conclusion, this study elucidates O-GlcNAcylation-dependent pathogenic mechanisms of Stxs and demonstrates that inhibition of aberrant O-GlcNAcylation is a potential approach to treat Stx-mediated diseases.
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Affiliation(s)
- Kyung‐Soo Lee
- Environmental Diseases Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
- Department of Biomolecular ScienceKRIBB School of BioscienceKorea University of Science and Technology (UST)DaejeonKorea
| | - Jieun Lee
- Environmental Diseases Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
| | - Pureum Lee
- Environmental Diseases Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
- Department of Biomolecular ScienceKRIBB School of BioscienceKorea University of Science and Technology (UST)DaejeonKorea
| | - Bong Chan Jeon
- Department of Biomolecular ScienceKRIBB School of BioscienceKorea University of Science and Technology (UST)DaejeonKorea
- Immunotherapy Convergence Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
| | - Min Yeong Song
- Environmental Diseases Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
- Department of Biomolecular ScienceKRIBB School of BioscienceKorea University of Science and Technology (UST)DaejeonKorea
| | - Sojung Kwak
- Environmental Diseases Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
| | - Jungwoon Lee
- Environmental Diseases Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
- Department of Biomolecular ScienceKRIBB School of BioscienceKorea University of Science and Technology (UST)DaejeonKorea
| | - Jun‐Seob Kim
- Department of Nano‐BioengineeringIncheon National UniversityIncheonKorea
| | - Doo‐Jin Kim
- Infectious Disease Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
| | - Ji Hyung Kim
- Infectious Disease Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
| | - Vernon L Tesh
- Department of Microbial Pathogenesis and ImmunologyCollege of MedicineTexas A&M UniversityBryanTXUSA
| | - Moo‐Seung Lee
- Environmental Diseases Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
- Department of Biomolecular ScienceKRIBB School of BioscienceKorea University of Science and Technology (UST)DaejeonKorea
| | - Sung‐Kyun Park
- Infectious Disease Research CenterKorea Research Institute of Bioscience & Biotechnology (KRIBB)DaejeonKorea
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Barani M, Zeeshan M, Kalantar-Neyestanaki D, Farooq MA, Rahdar A, Jha NK, Sargazi S, Gupta PK, Thakur VK. Nanomaterials in the Management of Gram-Negative Bacterial Infections. NANOMATERIALS 2021; 11:nano11102535. [PMID: 34684977 PMCID: PMC8540672 DOI: 10.3390/nano11102535] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/23/2021] [Accepted: 09/25/2021] [Indexed: 01/10/2023]
Abstract
The exploration of multiplexed bacterial virulence factors is a major problem in the early stages of Escherichia coli infection therapy. Traditional methods for detecting Escherichia coli (E. coli), such as serological experiments, immunoassays, polymerase chain reaction, and isothermal microcalorimetry have some drawbacks. As a result, detecting E. coli in a timely, cost-effective, and sensitive manner is critical for various areas of human safety and health. Intelligent devices based on nanotechnology are paving the way for fast and early detection of E. coli at the point of care. Due to their specific optical, magnetic, and electrical capabilities, nanostructures can play an important role in bacterial sensors. Another one of the applications involved use of nanomaterials in fighting microbial infections, including E. coli mediated infections. Various types of nanomaterials, either used directly as an antibacterial agent such as metallic nanoparticles (NPs) (silver, gold, zinc, etc.), or as a nanocarrier to deliver and target the antibiotic to the E. coli and its infected area. Among different types, polymeric NPs, lipidic nanocarriers, metallic nanocarriers, nanomicelles, nanoemulsion/ nanosuspension, dendrimers, graphene, etc. proved to be effective vehicles to deliver the drug in a controlled fashion at the targeted site with lower off-site drug leakage and side effects.
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Affiliation(s)
- Mahmood Barani
- Medical Mycology and Bacteriology Research Center, Kerman University of Medical Sciences, Kerman 7616913555, Iran; (M.B.); (D.K.-N.)
| | - Mahira Zeeshan
- Department of Pharmacy, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan;
| | - Davood Kalantar-Neyestanaki
- Medical Mycology and Bacteriology Research Center, Kerman University of Medical Sciences, Kerman 7616913555, Iran; (M.B.); (D.K.-N.)
- Department of Medical Microbiology (Bacteriology and virology), Afzalipour Faculty of Medicine, Kerman University of Medical Sciences, Kerman 7616913555, Iran
| | - Muhammad Asim Farooq
- Faculty of Pharmacy, Department of Pharmaceutics, The University of Lahore, Lahore 54000, Pakistan;
| | - Abbas Rahdar
- Department of Physics, University of Zabol, Zabol 9861335856, Iran
- Correspondence: (A.R.); (P.K.G.); (V.K.T.)
| | - Niraj Kumar Jha
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida 201310, India;
| | - Saman Sargazi
- Cellular and Molecular Research Center, Research Institute of Cellular and Molecular Sciences in Infectious Diseases, Zahedan University of Medical Sciences, Zahedan 9816743463, Iran;
| | - Piyush Kumar Gupta
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida 201310, India
- Correspondence: (A.R.); (P.K.G.); (V.K.T.)
| | - Vijay Kumar Thakur
- Biorefining and Advanced Materials Research Center, SRUC, Edinburgh EH9 3JG, UK
- Department of Mechanical Engineering, School of Engineering, Shiv Nadar University, Greater Noida 201314, India
- School of Engineering, University of Petroleum & Energy Studies (UPES), Dehradun 248007, India
- Correspondence: (A.R.); (P.K.G.); (V.K.T.)
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10
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Hughes AC, Patfield S, Rasooly R, He X. Validation of a Cell-Based Assay for Detection of Active Shiga Toxins Produced by Escherichia coli in Water. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17217901. [PMID: 33126550 PMCID: PMC7663042 DOI: 10.3390/ijerph17217901] [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] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 10/20/2020] [Accepted: 10/20/2020] [Indexed: 11/16/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) causes a wide spectrum of diseases, including hemorrhagic colitis and hemolytic uremic syndrome (HUS). Almost 5% of STEC infections result from waterborne exposures, yet there is no test listed in the EPA's current Selected Analytical Methods for the detection of active Shiga toxins (Stxs) in water. In this study, a HeLa cell-based assay is validated for the detection of metabolically active Stxs produced by STEC in water, including tap, bottled, and pond water. Active Stxs are detected even when the number of Stx-producing bacteria is less than 0.4 CFU/mL and the assay performance is not affected by background flora or chlorine in the water. This assay is not only as simple and affordable as cell-free assays but also detects active holotoxins without the use of live animals. In addition, the assay is designed for use in multi-well formats, making it ideal for high-throughput screening of water samples and therefore useful for environmental public health surveillance programs to reduce human risk of infection with STEC.
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Affiliation(s)
- Anna C. Hughes
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 800 Buchanan St., Albany, CA 94710, USA; (A.C.H.); (S.P.); (R.R.)
| | - Stephanie Patfield
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 800 Buchanan St., Albany, CA 94710, USA; (A.C.H.); (S.P.); (R.R.)
- Forensic Services Division, Contra Costa County Office of the Sheriff, 651 Pine St., Martinez, CA 94553, USA
| | - Reuven Rasooly
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 800 Buchanan St., Albany, CA 94710, USA; (A.C.H.); (S.P.); (R.R.)
| | - Xiaohua He
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 800 Buchanan St., Albany, CA 94710, USA; (A.C.H.); (S.P.); (R.R.)
- Correspondence: ; Tel.: +1-(510)-559-5823
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11
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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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Yang SC, Lin CH, Aljuffali IA, Fang JY. Current pathogenic Escherichia coli foodborne outbreak cases and therapy development. Arch Microbiol 2017; 199:811-825. [DOI: 10.1007/s00203-017-1393-y] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 05/15/2017] [Accepted: 05/30/2017] [Indexed: 11/30/2022]
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RBC Adherence of Immune Complexes Containing Botulinum Toxin Improves Neutralization and Macrophage Uptake. Toxins (Basel) 2017; 9:toxins9050173. [PMID: 28534855 PMCID: PMC5450721 DOI: 10.3390/toxins9050173] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/12/2017] [Accepted: 05/15/2017] [Indexed: 12/24/2022] Open
Abstract
In the paralytic disease botulism, the botulinum neurotoxin (BoNT) passes through the bloodstream to reach and inactivate neuromuscular junctions. Monoclonal antibodies (mAbs) may be useful BoNT countermeasures, as mAb combinations can rapidly clear BoNT from the blood circulation. We have previously shown that the BoNT-neutralizing potency of mAbs can be improved through red blood cell (RBC) immunoadherence. For example, a fusion protein (FP) that adheres biotinylated mAbs to the RBC surface enabled a pair of mAbs to neutralize 5000 LD50 BoNT/A in the mouse protection assay. Here, we added two mAbs to that combination, creating a 4-mAb:FP complex that neutralized 40,000 LD50 BoNT/A in vivo, and analyzed functional correlates of neutralization. The FP enhanced potency of BoNT/A immune complexes, providing the greatest magnitude of benefit to the 4-mAb combination. RBC binding of a BoNT/A complexed with 4-mAb:FP exhibited a bi-phasic clearance process in vivo. Most of the complexes were cleared within five minutes; the rest were cleared gradually over many hours. Peritoneal macrophages showed better uptake of the 4-mAb complex than the 3-mAb complex, and this was not affected by the presence of the FP. However, the addition of RBCs to the 4-mAb:FP BoNT/A doubled macrophage uptake of the complexes. Lastly, the 4-mAb:FP BoNT/A complex synergistically induced M2 macrophage polarization, as indicated by IL-10 expression, whether or not RBCs were present. RBC-targeted immunoadherence through the FP is a potent enhancer of mAb-mediated BoNT/A neutralization in vivo, and can have positive effects on BoNT/A sequestration, immune complex uptake, and macrophage activation.
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He X, Quiñones B, Loo MT, Loos S, Scavia G, Brigotti M, Levtchenko E, Monnens L. Serum Shiga toxin 2 values in patients during acute phase of diarrhoea-associated haemolytic uraemic syndrome. Acta Paediatr 2015; 104:e564-8. [PMID: 26361237 DOI: 10.1111/apa.13211] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 07/23/2015] [Accepted: 09/08/2015] [Indexed: 12/25/2022]
Abstract
AIM Shiga toxins are delivered via systemic circulation and are considered to be the cause of diarrhoea-associated haemolytic uraemic syndrome (HUS), as they injure endothelial cells, particularly in the glomeruli. This study measured Shiga toxin 2 (Stx2) in the serum of children affected in by HUS due to Stx2 producing Escherichia coli. METHODS The concentration of free Stx2 was measured in the serum of 16 children, collected immediately after admission to the clinic in the acute phase of HUS, using a sandwich enzyme-linked immunosorbent assay. The family members of two children were also investigated, with the relative toxicity of Stx2 assessed by a Vero cell-based fluorescent assay. RESULTS Stx2 was found in the serum of eight of the 16 children who were investigated. It was also detected in four of the six family members not showing symptomatic HUS, with an extremely high level in two. CONCLUSION An absent or rather low concentration of Stx2 was found in the serum of children admitted to the clinic with diarrhoea-associated HUS. The high concentration of Stx2 in family members without HUS, but mostly with watery diarrhoea and raised functional activity, was in line with the concept of early injury by Stx2.
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Affiliation(s)
- Xiaohua He
- US Department of Agriculture; ARS; WRRC; Foodborne Toxin Detection and Prevention Unit; Albany NY USA
| | - Beatriz Quiñones
- US Department of Agriculture; ARS; WRRC; Produce Safety and Microbiology Unit; Albany NY USA
| | - Maroeska Te Loo
- Department of Pediatrics; Radboud University Nijmegen Medical Center; Nijmegen The Netherlands
| | - Sebastian Loos
- Division of Pediatric Nephrology; Department of Pediatrics; University Medical Center; Hamburg Germany
| | - Gaia Scavia
- EU Reference Laboratory for E. coli; Instituto Superiore di Sanita; Rome Italy
| | - Maurizio Brigotti
- Dipartimento di Medicina Specialistica Diagnostica e Sperimentale; Sede di Patologia Generale; Universita di Bologna; Bologna Italy
| | - Elena Levtchenko
- Department of Pediatric Nephrology and Growth and Regeneration; University Hospitals Leuven; Leuven Belgium
| | - Leo Monnens
- Department of Physiology; Radboud University; Nijmegen Medical Center; Nijmegen The Netherlands
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An in vitro combined antibiotic-antibody treatment eliminates toxicity from Shiga toxin-producing Escherichia coli. Antimicrob Agents Chemother 2015; 59:5435-44. [PMID: 26100707 DOI: 10.1128/aac.00763-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 06/16/2015] [Indexed: 12/11/2022] Open
Abstract
Treating Shiga toxin-producing Escherichia coli (STEC) gastrointestinal infections is difficult. The utility of antibiotics for STEC treatment is controversial, since antibiotic resistance among STEC isolates is widespread and certain antibiotics dramatically increase the expression of Shiga toxins (Stxs), which are some of the most important virulence factors in STEC. Stxs contribute to life-threatening hemolytic uremic syndrome (HUS), which develops in considerable proportions of patients with STEC infections. Understanding the antibiotic resistance profiles of STEC isolates and the Stx induction potential of promising antibiotics is essential for evaluating any antibiotic treatment of STEC. In this study, 42 O157:H7 or non-O157 STEC isolates (including the "big six" serotypes) were evaluated for their resistance against 22 antibiotics by using an antibiotic array. Tigecycline inhibited the growth of all of the tested STEC isolates and also inhibited the production of Stxs (Stx2 in particular). In combination with neutralizing antibodies to Stx1 and Stx2, the tigecycline-antibody treatment fully protected Vero cells from Stx toxicity, even when the STEC bacteria and the Vero cells were cultured together. The combination of an antibiotic such as tigecycline with neutralizing antibodies presents a promising strategy for future STEC treatments.
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Wang F, Gao W, Thamphiwatana S, Luk BT, Angsantikul P, Zhang Q, Hu CMJ, Fang RH, Copp JA, Pornpattananangkul D, Lu W, Zhang L. Hydrogel Retaining Toxin-Absorbing Nanosponges for Local Treatment of Methicillin-Resistant Staphylococcus aureus Infection. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2015; 27:3437-43. [PMID: 25931231 PMCID: PMC4461515 DOI: 10.1002/adma.201501071] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 03/29/2015] [Indexed: 05/02/2023]
Affiliation(s)
- Fei Wang
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
- Department of Pharmaceutics, School of Pharmacy, Fudan University, and Key Laboratory of Smart Drug Delivery (Fudan University), Ministry of Education, Shanghai 201203, P. R. China
| | - Weiwei Gao
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Soracha Thamphiwatana
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Brian T. Luk
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Pavimol Angsantikul
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Qiangzhe Zhang
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Che-Ming J. Hu
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ronnie H. Fang
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jonathan A. Copp
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Weiyue Lu
- Department of Pharmaceutics, School of Pharmacy, Fudan University, and Key Laboratory of Smart Drug Delivery (Fudan University), Ministry of Education, Shanghai 201203, P. R. China
| | - Liangfang Zhang
- Department of NanoEngineering and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
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Luz D, Chen G, Maranhão AQ, Rocha LB, Sidhu S, Piazza RMF. Development and characterization of recombinant antibody fragments that recognize and neutralize in vitro Stx2 toxin from Shiga toxin-producing Escherichia coli. PLoS One 2015; 10:e0120481. [PMID: 25790467 PMCID: PMC4366190 DOI: 10.1371/journal.pone.0120481] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 01/22/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Stx toxin is a member of the AB5 family of bacterial toxins: the active A subunit has N-glycosidase activity against 28S rRNA, resulting in inhibition of protein synthesis in eukaryotic cells, and the pentamer ligand B subunits (StxB) bind to globotria(tetra)osylceramide receptors (Gb3/Gb4) on the cell membrane. Shiga toxin-producing Escherichia coli strains (STEC) may produce Stx1 and/or Stx2 and variants. Strains carrying Stx2 are considered more virulent and related to the majority of outbreaks, besides being usually associated with hemolytic uremic syndrome in humans. The development of tools for the detection and/or neutralization of these toxins is a turning point for early diagnosis and therapeutics. Antibodies are an excellent paradigm for the design of high-affinity, protein-based binding reagents used for these purposes. METHODS AND FINDINGS In this work, we developed two recombinant antibodies; scFv fragments from mouse hybridomas and Fab fragments by phage display technology using a human synthetic antibody library. Both fragments showed high binding affinity to Stx2, and they were able to bind specifically to the GKIEFSKYNEDDTF region of the Stx2 B subunit and to neutralize in vitro the cytotoxicity of the toxin up to 80%. Furthermore, the scFv fragments showed 79% sensitivity and 100% specificity in detecting STEC strains by ELISA. CONCLUSION In this work, we developed and characterized two recombinant antibodies against Stx2, as promising tools to be used in diagnosis or therapeutic approaches against STEC, and for the first time, we showed a human monovalent molecule, produced in bacteria, able to neutralize the cytotoxicity of Stx2 in vitro.
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Affiliation(s)
- Daniela Luz
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Gang Chen
- Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | | | - Leticia B. Rocha
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Sachdev Sidhu
- Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Roxane M. F. Piazza
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
- * E-mail:
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Jenko KL, Zhang Y, Kostenko Y, Fan Y, Garcia-Rodriguez C, Lou J, Marks JD, Varnum SM. Development of an ELISA microarray assay for the sensitive and simultaneous detection of ten biodefense toxins. Analyst 2014; 139:5093-102. [PMID: 25112421 PMCID: PMC6540756 DOI: 10.1039/c4an01270d] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Plant and microbial toxins are considered bioterrorism threat agents because of their extreme toxicity and/or ease of availability. Additionally, some of these toxins are increasingly responsible for accidental food poisonings. The current study utilized an ELISA-based protein antibody microarray for the multiplexed detection of ten biothreat toxins, botulinum neurotoxins (BoNT) A, B, C, D, E, F, ricin, shiga toxins 1 and 2 (Stx), and staphylococcus enterotoxin B (SEB), in buffer and complex biological matrices. The multiplexed assay displayed a sensitivity of 1.3 pg mL(-1) (BoNT/A, BoNT/B, SEB, Stx-1 and Stx-2), 3.3 pg mL(-1) (BoNT/C, BoNT/E, BoNT/F) and 8.2 pg mL(-1) (BoNT/D, ricin). All assays demonstrated high accuracy (75-120 percent recovery) and reproducibility (most coefficients of variation <20%). Quantification curves for the ten toxins were also evaluated in clinical samples (serum, plasma, nasal fluid, saliva, stool, and urine) and environmental samples (apple juice, milk and baby food) with overall minimal matrix effects. The multiplex assays were highly specific, with little cross-reactivity observed between the selected toxin antibodies. The results demonstrate a multiplex microarray that improves current immunoassay sensitivity for biological warfare agents in buffer, clinical, and environmental samples.
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Affiliation(s)
- Kathryn L Jenko
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99354, USA.
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Skinner C, Patfield S, Stanker LH, Fratamico P, He X. New high-affinity monoclonal antibodies against Shiga toxin 1 facilitate the detection of hybrid Stx1/Stx2 in vivo. PLoS One 2014; 9:e99854. [PMID: 24914553 PMCID: PMC4051773 DOI: 10.1371/journal.pone.0099854] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 05/16/2014] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Shiga toxin-producing E. coli (STEC) are a group of common and potentially deadly intestinal pathogens expressing Shiga toxin (Stx) as a primary virulence factor. Of the two types of Stx, Stx2 is responsible for more severe symptoms during infection, while Stx1 is almost identical to the Shiga toxin from Shigella dysenteriae, a ubiquitous pathogen in developing countries. Although antibodies against Stx1 have been reported, few have reached the affinity needed for assembling highly sensitive immunoassays. Sensitive and affordable immunoassays for Stx1 and Stx2 could help improve detection of STEC in livestock, food, the environment, and in clinical samples resulting in improved food safety and human health. METHOD AND FINDINGS Three new monoclonal antibodies (mAbs) against the B subunit of Stx1 were generated using recombinant toxoid Stx1E167Q and hybridoma technology. These new mAbs recognize all subtypes of Stx1, but do not cross-react with any subtype of Stx2. In addition, they exhibited the ability to neutralize Stx1 toxicity in Vero cell assays. An optimized sandwich ELISA using of a pair of these mAbs had a limit of detection of 8.7 pg/mL, which is superior to any existing assay of this kind. Using one of these Stx1 mAbs in concert with Stx2 mAbs, the presence of hybrid Stx1/Stx2 toxin in the culture media of STEC strains that express both Stx1 and Stx2 was demonstrated. CONCLUSIONS These new mAbs provide a mix of availability, utility, versatility, and most importantly, increased sensitivity for detection of Stx1. There are numerous potential applications for these mAbs, including low-cost detection assays and therapeutic use. Analysis of hybrid Stx1/2 could provide new insights on the structure, activity, and cellular targets of Shiga toxins.
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Affiliation(s)
- Craig Skinner
- Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, Albany, California, United States of America
| | - Stephanie Patfield
- Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, Albany, California, United States of America
| | - Larry H. Stanker
- Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, Albany, California, United States of America
| | - Pina Fratamico
- Eastern Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, Wyndmoor, Pennslvania, United States of America
| | - Xiaohua He
- Western Regional Research Center, U.S. Department of Agriculture, Agricultural Research Service, Albany, California, United States of America
- * E-mail:
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A monoclonal antibody based capture ELISA for botulinum neurotoxin serotype B: toxin detection in food. Toxins (Basel) 2013; 5:2212-26. [PMID: 24253240 PMCID: PMC3847722 DOI: 10.3390/toxins5112212] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 10/30/2013] [Accepted: 11/07/2013] [Indexed: 12/12/2022] Open
Abstract
Botulism is a serious foodborne neuroparalytic disease, caused by botulinum neurotoxin (BoNT), produced by the anaerobic bacterium Clostridium botulinum. Seven toxin serotypes (A – H) have been described. The majority of human cases of botulism are caused by serotypes A and B followed by E and F. We report here a group of serotype B specific monoclonal antibodies (mAbs) capable of binding toxin under physiological conditions. Thus, they serve as capture antibodies for a sandwich (capture) ELISA. The antibodies were generated using recombinant peptide fragments corresponding to the receptor-binding domain of the toxin heavy chain as immunogen. Their binding properties suggest that they bind a complex epitope with dissociation constants (KD’s) for individual antibodies ranging from 10 to 48 × 10−11 M. Assay performance for all possible combinations of capture-detector antibody pairs was evaluated and the antibody pair resulting in the lowest level of detection (L.O.D.), ~20 pg/mL was determined. Toxin was detected in spiked dairy samples with good recoveries at concentrations as low as 0.5 pg/mL and in ground beef samples at levels as low as 2 ng/g. Thus, the sandwich ELISA described here uses mAb for both the capture and detector antibodies (binding different epitopes on the toxin molecule) and readily detects toxin in those food samples tested.
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