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Rasetti-Escargueil C, Popoff MR. Recent Developments in Botulinum Neurotoxins Detection. Microorganisms 2022; 10:microorganisms10051001. [PMID: 35630444 PMCID: PMC9145529 DOI: 10.3390/microorganisms10051001] [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] [Received: 04/01/2022] [Revised: 04/29/2022] [Accepted: 05/03/2022] [Indexed: 02/04/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are produced as protein complexes by bacteria of the genus Clostridium that are Gram-positive, anaerobic and spore forming (Clostridium botulinum, C. butyricum, C. baratii and C. argentinense spp.). BoNTs show a high immunological and genetic diversity. Therefore, fast, precise, and more reliable detection methods are still required to monitor outbreaks and ensure surveillance of botulism. The botulinum toxin field also comprises therapeutic uses, basic research studies and biodefense issues. This review presents currently available detection methods, and new methods offering the potential of enhanced precision and reproducibility. While the immunological methods offer a range of benefits, such as rapid analysis time, reproducibility and high sensitivity, their implementation is subject to the availability of suitable tools and reagents, such as specific antibodies. Currently, the mass spectrometry approach is the most sensitive in vitro method for a rapid detection of active or inactive forms of BoNTs. However, these methods require inter-laboratory validation before they can be more widely implemented in reference laboratories. In addition, these surrogate in vitro models also require full validation before they can be used as replacement bioassays of potency. Cell-based assays using neuronal cells in culture recapitulate all functional steps of toxin activity, but are still at various stages of development; they are not yet sufficiently robust, due to high batch-to-batch cell variability. Cell-based assays have a strong potential to replace the mouse bioassay (MBA) in terms of BoNT potency determination in pharmaceutical formulations; they can also help to identify suitable inhibitors while reducing the number of animals used. However, the development of safe countermeasures still requires the use of in vivo studies to complement in vitro immunological or cell-based approaches.
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2
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Wang J, Xu H, Zhang C, Chen J, Wang C, Li X, Zhang Y, Xie J. Serotype Features of 17 Suspected Cases of Foodborne Botulism in China 2019-2022 Revealed by a Multiplex Immuno-Endopep-MS Method. Front Microbiol 2022; 13:869874. [PMID: 35450283 PMCID: PMC9016322 DOI: 10.3389/fmicb.2022.869874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 03/04/2022] [Indexed: 11/13/2022] Open
Abstract
Diagnosis of botulism caused by multiple serotypes of botulinum neurotoxin (BoNT) is still a challenge due to the lack of a reliable detection method. The present study develops a feasible laboratorial method based on an isotope dilution Immuno-Endopep-MS to detect BoNTs and determine their serotypes and activities in clinical samples. Eleven positive foodborne botulism cases out of a total of 17 suspected cases in China, 2019–2022, were determined by the established method. Blood, urine, vomitus, gastric mucosa samples, and food samples were employed and evidenced to be suitable for the detection. Results showed that, although single type A-intoxication was still the first cause among these foodborne botulism cases, other causes involving type E, type B, and their mixed types were also determined, providing a glimpse to the serotype profile of botulism happened in recent years in China. Furthermore, in order to provide insights into in vivo profiles of toxin serotypes, a comprehensive analysis of clinical specimens collected from one family of four patients was performed during a clinically and therapeutically relevant time frame. Serotypes and concentrations of BoNT in specimens revealed a good correlation with symptoms and progresses of disease. Additionally, serum was proved to be more suitable for detection of BoNT/A with a detection window up to 12 days. A urine sample, although rarely reported for foodborne botulism diagnosis, was validated to be suitable for testing BoNTs, with a longer detection window up to 25 days. To the best of our knowledge, this is the first comprehensive analytical research on in vivo profiles of serotypes A, B, and E in different types of specimens from mixed botulism cases. Our method and findings facilitate the toxin detection and identification by clinical diagnostic laboratories.
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Affiliation(s)
- Jiang Wang
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Hua Xu
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Cheng Zhang
- Yongding Road Outpatient Department, Jingnan Medical District of Chinese PLA General Hospital, Beijing, China
| | - Jia Chen
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Chunyan Wang
- Poisoning Treatment Department, The Fifth Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Xinying Li
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Yajiao Zhang
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Jianwei Xie
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
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3
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Plößl T, Vujtovic-Ockenga N, Kehrenberg C, Klaubert B. Multi-dimensional nanoscale liquid chromatography and nano-electrospray ion-trap mass spectrometry for detection of Clostridium botulinum type C and the produced botulinum neurotoxin type C complex. J Microbiol Methods 2021; 193:106397. [PMID: 34952090 DOI: 10.1016/j.mimet.2021.106397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/16/2021] [Accepted: 12/16/2021] [Indexed: 12/18/2022]
Abstract
Botulinum neurotoxin types C, D and their mosaic forms C/D and D/C produced mainly by Clostridium botulinum types C and D cause botulism in animals and belong to the most toxic substances for poultry and fish. In addition to intoxications, also toxoinfections with C. botulinum types C and D play a role that should not be underestimated, especially in veterinary medicine. Contrary to other botulinum neurotoxin complexes (BT x), the biosynthesis of these types is phage-encoded. Currently, the gold standard for neurotoxin detection in cases of clinical botulism is the mouse bioassay. In the last few years, alternatives for replacing this mouse bioassay have become increasingly interesting for the detection and characterisation of botulinum neurotoxins. Therefore, immunological techniques based mainly on antibodies, PCR or mass spectral methods have been developed. In this context, the most promising development is that of different endopeptidase assays. In our study, we were able to show that the 2D-nano-LC-MS/MS method presented by Klaubert et al. 2009 especially for detecting BT x A, B, E and F in complex culture media can also be used for detecting BT x C. The focus was therefore on transferring this method to detecting BT x C and pointing out necessary modifications of this current method. For method development, we used different culture preparations and sample conditions. To find out whether BT x C is just as stable against acetic peptic pretreatment as other BT x, we used sample preparations with and without peptic pretreatment. The decisive difference to previous publications is the detection of produced BT x C directly from culture supernatant of different strains of C. botulinum type C. In addition, we present a new approach of detecting protein fragments from C3 and C2 toxin and some specific host cell proteins of the bacterium Clostridium spp. in order to specify the carrier bacterium, therefore verifying the presence of an intact neurotoxin-encoding phage also without directly detecting BT x C and thus the possibility to produce neurotoxin. Herein, we describe a new method to examine environmental samples or suspected feed samples in cases of toxoinfections as well as finding out the causes of clinical botulism. This new approach is particularly interesting for veterinary medicine, especially for diseases like chronic botulism in cows or equine grass sickness.
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Affiliation(s)
- Tanja Plößl
- Supervisory Centre South for Public Law Tasks of the Bundeswehr Medical Service, Dachauer Straße 128, 80637 München, Germany.
| | - Nada Vujtovic-Ockenga
- Central Institute of the Bundeswehr Medical Service Munich, Ingolstädter Landstraße 102, 85748 Garching-Hochbrück, Germany
| | - Corinna Kehrenberg
- Institute for Veterinary Food Science, Justus-Liebig-University, Frankfurter Straße 92, 35392 Gießen, Germany
| | - Bernd Klaubert
- Federal Ministry of Health, Friedrichstraße 108, 10117 Berlin, Germany
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4
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Nepal MR, Jeong TC. Alternative Methods for Testing Botulinum Toxin: Current Status and Future Perspectives. Biomol Ther (Seoul) 2020; 28:302-310. [PMID: 32126735 PMCID: PMC7327137 DOI: 10.4062/biomolther.2019.200] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 02/06/2020] [Accepted: 02/17/2020] [Indexed: 01/29/2023] Open
Abstract
Botulinum toxins are neurotoxic modular proteins composed of a heavy chain and a light chain connected by a disulfide bond and are produced by Clostridium botulinum. Although lethally toxic, botulinum toxin in low doses is clinically effective in numerous medical conditions, including muscle spasticity, strabismus, hyperactive urinary bladder, excessive sweating, and migraine. Globally, several companies are now producing products containing botulinum toxin for medical and cosmetic purposes, including the reduction of facial wrinkles. To test the efficacy and toxicity of botulinum toxin, animal tests have been solely and widely used, resulting in the inevitable sacrifice of hundreds of animals. Hence, alternative methods are urgently required to replace animals in botulinum toxin testing. Here, the various alternative methods developed to test the toxicity and efficacy of botulinum toxins have been briefly reviewed and future perspectives have been detailed.
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Affiliation(s)
- Mahesh Raj Nepal
- College of Pharmacy, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Tae Cheon Jeong
- College of Pharmacy, Yeungnam University, Gyeongsan 38541, Republic of Korea
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5
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Kalb SR, Baudys J, Kiernan K, Wang D, Becher F, Barr JR. Proposed BoNT/A and /B Peptide Substrates Cannot Detect Multiple Subtypes in the Endopep-MS Assay. J Anal Toxicol 2020; 44:173-179. [PMID: 31287544 DOI: 10.1093/jat/bkz044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/24/2019] [Accepted: 04/27/2019] [Indexed: 11/14/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are a family of protein toxins consisting of seven known serotypes (BoNT/A-BoNT/G) and multiple subtypes within the serotypes, and all of which cause the disease botulism-a disease of great public health concern. Accurate detection of BoNTs in human clinical samples is therefore an important public health goal. To achieve this goal, our laboratory developed a mass spectrometry-based assay detecting the presence of BoNT via its enzymatic activity on a peptide substrate. Recently, publications reported the use of new peptide substrates to detect BoNT/A and /B with improved results over other peptide substrates. However, the authors did not provide results of their peptide substrate on multiple subtypes of BoNT. In this work, we describe the results of testing the new substrates with multiple BoNT/A and /B subtypes and find that the substrates cannot detect many subtypes of BoNT/A and /B.
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Affiliation(s)
- Suzanne R Kalb
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - Jakub Baudys
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - Kaitlyn Kiernan
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - Dongxia Wang
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - François Becher
- Service de Pharmacologie et Immunoanalyse, Laboratoire d'Etude du Métabolisme des Médicaments, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Institut National de la Recherche Agronomique, Université Paris Saclay, Gif-sur-Yvette, France
| | - John R Barr
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
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6
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Thirunavukkarasu N, Johnson E, Pillai S, Hodge D, Stanker L, Wentz T, Singh B, Venkateswaran K, McNutt P, Adler M, Brown E, Hammack T, Burr D, Sharma S. Botulinum Neurotoxin Detection Methods for Public Health Response and Surveillance. Front Bioeng Biotechnol 2018; 6:80. [PMID: 29988463 PMCID: PMC6024544 DOI: 10.3389/fbioe.2018.00080] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/30/2018] [Indexed: 01/06/2023] Open
Abstract
Botulism outbreak due to consumption of food contaminated with botulinum neurotoxins (BoNTs) is a public health emergency. The threat of bioterrorism through deliberate distribution in food sources and/or aerosolization of BoNTs raises global public health and security concerns due to the potential for high mortality and morbidity. Rapid and reliable detection methods are necessary to support clinical diagnosis and surveillance for identifying the source of contamination, performing epidemiological analysis of the outbreak, preventing and responding to botulism outbreaks. This review considers the applicability of various BoNT detection methods and examines their fitness-for-purpose in safeguarding the public health and security goals.
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Affiliation(s)
- Nagarajan Thirunavukkarasu
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States
| | - Eric Johnson
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, United States
| | - Segaran Pillai
- U.S. Food and Drug Administration Office of Laboratory Science and Safety, Silver Spring, MD, United States
| | - David Hodge
- Chemical and Biological Defense Division, Science and Technology Directorate, U.S. Department of Homeland Security, Washington, DC, United States
| | - Larry Stanker
- U.S. Department of Agriculture, Agriculture Research Service Albany, Albany, CA, United States
| | - Travis Wentz
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States
| | - BalRam Singh
- Institute of Advanced Sciences, Botulinum Research Center, Dartmouth, MA, United States
| | | | - Patrick McNutt
- United States Army Medical Research Institute of Chemical Defense, Aberdeen, MD, United States
| | - Michael Adler
- United States Army Medical Research Institute of Chemical Defense, Aberdeen, MD, United States
| | - Eric Brown
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States
| | - Thomas Hammack
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States
| | - Donald Burr
- Office of Regulatory Affairs, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Silver Spring, MD, United States
| | - Shashi Sharma
- Division of Microbiology, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States
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7
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Development of a multiplex Endopep-MS assay for simultaneous detection of botulinum toxins A, B and E. Sci Rep 2017; 7:14859. [PMID: 29093524 PMCID: PMC5665860 DOI: 10.1038/s41598-017-14911-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 10/16/2017] [Indexed: 11/25/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are bacterial proteins that cause botulism, a life-threatening disease. The Endopep-MS assay permits rapid detection and serotypic differential diagnosis of BoNTs. The serotype-specific nature of this assay requires that each serum sample be aliquoted and individually tested, which in addition to the limited volume of clinical samples, especially in infants, points to the need for a multiplex assay. However, previous attempts to develop such an assay have been challenging, mainly due to inhibition of BoNT/A activity by the BoNT/E peptide substrate. BoNT/A and BoNT/E share the same native target protein as their substrate. We hypothesized that the steric interference between the BoNT/A and BoNT/E substrate peptides is responsible for the difficulty in simultaneously assaying these two toxins. To explore the basis for steric interference, we used the reported structure of BoNT/A in complex with SNAP-25 and modelled the structure of BoNT/E with SNAP-25. Following this thorough structural analysis, we designed a new peptide substrate for BoNT/A that maintained the assay sensitivity and allowed, for the first time, simultaneous detection of the three most abundant human botulinum serotypes. Adopting the multiplex assay will minimize the required sample volume and assay time for botulinum detection while maintaining the superior Endopep-MS assay performance.
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8
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Torgeman A, Ozeri E, Ben David A, Diamant E, Rosen O, Schwartz A, Barnea A, Makovitzki A, Mimran A, Zichel R. Role of Homologous Fc Fragment in the Potency and Efficacy of Anti-Botulinum Antibody Preparations. Toxins (Basel) 2017; 9:toxins9060180. [PMID: 28555060 PMCID: PMC5488030 DOI: 10.3390/toxins9060180] [Citation(s) in RCA: 9] [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: 04/25/2017] [Revised: 05/24/2017] [Accepted: 05/27/2017] [Indexed: 12/12/2022] Open
Abstract
The only approved treatment for botulism relies on passive immunity which is mostly based on antibody preparations collected from hyper-immune horses. The IgG Fc fragment is commonly removed from these heterologous preparations to reduce the incidence of hyper-sensitivity reactions. New-generation therapies entering the pipeline are based on a combination of humanized monoclonal antibodies (MAbs), which exhibit improved safety and pharmacokinetics. In the current study, a systematic and quantitative approach was applied to measure the direct contribution of homologous Fc to the potency of monoclonal and polyclonal antitoxin preparations in mice. Homologous Fc increased the potency of three individual anti-botulinum toxin MAbs by up to one order of magnitude. Moreover, Fc fragment removal almost completely abolished the synergistic potency obtained from a combined preparation of these three MAbs. The MAb mixture neutralized a 400-mouse median lethal dose (MsLD50) of botulinum toxin, whereas the F(ab′)2 combination failed to neutralize 10 MsLD50 of botulinum toxin. Notably, increased avidity did not compensate for this phenomenon, as a polyclonal, hyper-immune, homologous preparation lost 90% of its potency as well upon Fc removal. Finally, the addition of homologous Fc arms to a heterologous pharmaceutical anti-botulinum toxin polyclonal horse F(ab′)2 preparation improved its efficacy when administered to intoxicated symptomatic mice. Our study extends the aspects by which switching from animal-based to human-based antitoxins will improve not only the safety but also the potency and efficacy of passive immunity against toxins.
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Affiliation(s)
- Amram Torgeman
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Eyal Ozeri
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Alon Ben David
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Eran Diamant
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Osnat Rosen
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Arieh Schwartz
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Ada Barnea
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Arik Makovitzki
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Avishai Mimran
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Ran Zichel
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
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9
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Rosen O, Feldberg L, Dor E, Gura S, Zichel R. Optimization of SNAP-25-derived peptide substrate for improved detection of botulinum A in the Endopep-MS assay. Anal Biochem 2017; 528:34-37. [PMID: 28450105 DOI: 10.1016/j.ab.2017.04.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 12/24/2022]
Abstract
Botulinum neurotoxins (BoNTs) are the most toxic proteins in nature. Endopeptidase-mass-spectrometry (Endopep-MS) is used as a specific and rapid in-vitro assay to detect BoNTs. In this assay, immunocaptured toxin cleaves a serotype-specific-peptide-substrate, and the cleavage products are then detected by MS. Here we describe the design of a new peptide substrate for improved detection of BoNT type A (BoNT/A). Our strategy was based on reported BoNT/A-SNAP-25 interactions integrated with analysis method efficiency considerations. Integration of the newly designed substrate led to a 10-fold increase in the assay sensitivity both in buffer and in clinically relevant samples.
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Affiliation(s)
- Osnat Rosen
- Department of Biotechnology, Israel Institute for Biological Research, Israel
| | - Liron Feldberg
- Department of Analytical Chemistry, Israel Institute for Biological Research, Israel
| | - Eyal Dor
- Department of Biotechnology, Israel Institute for Biological Research, Israel
| | - Sigalit Gura
- Department of Analytical Chemistry, Israel Institute for Biological Research, Israel
| | - Ran Zichel
- Department of Biotechnology, Israel Institute for Biological Research, Israel.
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10
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Development of an Innovative in Vitro Potency Assay for Anti-Botulinum Antitoxins. Toxins (Basel) 2016; 8:toxins8100276. [PMID: 27669303 PMCID: PMC5086636 DOI: 10.3390/toxins8100276] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 09/14/2016] [Accepted: 09/19/2016] [Indexed: 11/17/2022] Open
Abstract
Botulinum neurotoxins are bacterial proteins that cause botulism, a life-threatening disease. Therapy relies mostly on post-intoxication antibody treatment. The only accepted method to measure the potency of, and to approve, antitoxin preparations is the mouse lethality neutralization bioassay. However, this assay is time-consuming, labor-intensive, costly, and raises ethical issues related to the large numbers of laboratory animals needed. Until now, all efforts to develop an alternative in vitro assay have not provided a valid replacement to the mouse potency assay. In the present study, we report the development of an innovative in vitro assay for determining botulinum antitoxin potency, using botulinum type B as a model. The concept of the assay is to mimic two fundamental steps in botulinum intoxication: receptor binding and catalytic activity. By simulating these steps in vitro we were able to accurately determine the potency of antitoxin preparations. The reproducibility of the assay was high with a CV < 13%. Most importantly, the antitoxin potency measured by the in vitro assay highly correlated with that measured by the standard in vivo mouse assay (r = 0.9842, p < 0.0001). Thus, this new in vitro assay has the potential to be considered, after validation, as a replacement to the mouse assay for quantitating neutralizing antibody concentrations in pharmaceutical botulinum antitoxin preparations. Future adoption of this in vitro assay would minimize the use of laboratory animals, speed up the time, and reduce the cost of botulinum antitoxin approval.
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11
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Berger T, Eisenkraft A, Bar-Haim E, Kassirer M, Aran AA, Fogel I. Toxins as biological weapons for terror-characteristics, challenges and medical countermeasures: a mini-review. DISASTER AND MILITARY MEDICINE 2016; 2:7. [PMID: 28265441 PMCID: PMC5330008 DOI: 10.1186/s40696-016-0017-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 04/23/2016] [Indexed: 12/15/2022]
Abstract
Toxins are hazardous biochemical compounds derived from bacteria, fungi, or plants. Some have mechanisms of action and physical properties that make them amenable for use as potential warfare agents. Currently, some toxins are classified as potential biological weapons, although they have several differences from classic living bio-terror pathogens and some similarities to manmade chemical warfare agents. This review focuses on category A and B bio-terror toxins recognized by the Centers for Disease Control and Prevention: Botulinum neurotoxin, staphylococcal enterotoxin B, Clostridium perfringens epsilon toxin, and ricin. Their derivation, pathogenesis, mechanism of action, associated clinical signs and symptoms, diagnosis, and treatment are discussed in detail. Given their expected covert use, the primary diagnostic challenge in toxin exposure is the early detection of morbidity clusters, apart from background morbidity, after a relatively short incubation period. For this reason, it is important that clinicians be familiar with the clinical manifestations of toxins and the appropriate methods of management and countermeasures.
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Affiliation(s)
- Tamar Berger
- Surgeon General Headquarters, IDF Medical Corps, Tel Hashomer, Israel ; Department of Internal Medicine, Rabin Medical Center, Petah Tikva, Israel
| | - Arik Eisenkraft
- Surgeon General Headquarters, IDF Medical Corps, Tel Hashomer, Israel ; Institute for Research in Military Medicine, Faculty of Medicine, The Hebrew University, Jerusalem, Israel ; NBC Protection Division, IMOD, Tel-Aviv, Israel
| | - Erez Bar-Haim
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Michael Kassirer
- Surgeon General Headquarters, IDF Medical Corps, Tel Hashomer, Israel
| | - Adi Avniel Aran
- Surgeon General Headquarters, IDF Medical Corps, Tel Hashomer, Israel ; Pediatric Critical Care Unit, Children's Hospital, Montefiore Medical Center, Bronx, NY USA
| | - Itay Fogel
- Surgeon General Headquarters, IDF Medical Corps, Tel Hashomer, Israel
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12
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Rosen O, Feldberg L, Gura S, Brosh-Nissimov T, Guri A, Zimhony O, Shapiro E, Beth-Din A, Stein D, Ozeri E, Barnea A, Turgeman A, Ben David A, Schwartz A, Elhanany E, Diamant E, Yitzhaki S, Zichel R. Early, Real-Time Medical Diagnosis of Botulism by Endopeptidase-Mass Spectrometry. Clin Infect Dis 2015; 61:e58-61. [PMID: 26420800 DOI: 10.1093/cid/civ861] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 09/17/2015] [Indexed: 11/14/2022] Open
Abstract
Botulinum toxin was detected in patient serum using Endopeptidase-mass-spectrometry assay, although all conventional tests provided negative results. Antitoxin was administered, resulting in patient improvement. Implementing this highly sensitive and rapid assay will improve preparedness for foodborne botulism and deliberate exposure.
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Affiliation(s)
| | | | | | - Tal Brosh-Nissimov
- CBRN Medicine Branch, Medical Corps HQ, Israel Institute for Biological Research, Ness Ziona
| | | | | | - Eli Shapiro
- Pediatric Intensive Care Unit, Kaplan Medical Center, Rehovot
| | - Adi Beth-Din
- Department of Biochemistry and Molecular Genetics
| | - Dana Stein
- Department of Biochemistry and Molecular Genetics
| | | | | | | | | | | | | | | | - Shmuel Yitzhaki
- Department of Infectious Diseases, Israel Institute for Biological Research, Ness Ziona, Israel
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13
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Kalb SR, Boyer AE, Barr JR. Mass Spectrometric Detection of Bacterial Protein Toxins and Their Enzymatic Activity. Toxins (Basel) 2015; 7:3497-511. [PMID: 26404376 PMCID: PMC4591662 DOI: 10.3390/toxins7093497] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 08/10/2015] [Accepted: 08/26/2015] [Indexed: 01/15/2023] Open
Abstract
Mass spectrometry has recently become a powerful technique for bacterial identification. Mass spectrometry approaches generally rely upon introduction of the bacteria into a matrix-assisted laser-desorption time-of-flight (MALDI-TOF) mass spectrometer with mass spectrometric recognition of proteins specific to that organism that form a reliable fingerprint. With some bacteria, such as Bacillus anthracis and Clostridium botulinum, the health threat posed by these organisms is not the organism itself, but rather the protein toxins produced by the organisms. One such example is botulinum neurotoxin (BoNT), a potent neurotoxin produced by C. botulinum. There are seven known serotypes of BoNT, A–G, and many of the serotypes can be further differentiated into toxin variants, which are up to 99.9% identical in some cases. Mass spectrometric proteomic techniques have been established to differentiate the serotype or toxin variant of BoNT produced by varied strains of C. botulinum. Detection of potent biological toxins requires high analytical sensitivity and mass spectrometry based methods have been developed to determine the enzymatic activity of BoNT and the anthrax lethal toxins produced by B. anthracis. This enzymatic activity, unique for each toxin, is assessed with detection of the toxin-induced cleavage of strategically designed peptide substrates by MALDI-TOF mass spectrometry offering unparalleled specificity. Furthermore, activity assays allow for the assessment of the biological activity of a toxin and its potential health risk. Such methods have become important diagnostics for botulism and anthrax. Here, we review mass spectrometry based methods for the enzymatic activity of BoNT and the anthrax lethal factor toxin.
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Affiliation(s)
- Suzanne R Kalb
- Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA.
| | - Anne E Boyer
- Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA.
| | - John R Barr
- Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA.
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Manes NP, Mann JM, Nita-Lazar A. Selected Reaction Monitoring Mass Spectrometry for Absolute Protein Quantification. J Vis Exp 2015:e52959. [PMID: 26325288 DOI: 10.3791/52959] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Absolute quantification of target proteins within complex biological samples is critical to a wide range of research and clinical applications. This protocol provides step-by-step instructions for the development and application of quantitative assays using selected reaction monitoring (SRM) mass spectrometry (MS). First, likely quantotypic target peptides are identified based on numerous criteria. This includes identifying proteotypic peptides, avoiding sites of posttranslational modification, and analyzing the uniqueness of the target peptide to the target protein. Next, crude external peptide standards are synthesized and used to develop SRM assays, and the resulting assays are used to perform qualitative analyses of the biological samples. Finally, purified, quantified, heavy isotope labeled internal peptide standards are prepared and used to perform isotope dilution series SRM assays. Analysis of all of the resulting MS data is presented. This protocol was used to accurately assay the absolute abundance of proteins of the chemotaxis signaling pathway within RAW 264.7 cells (a mouse monocyte/macrophage cell line). The quantification of Gi2 (a heterotrimeric G-protein α-subunit) is described in detail.
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Affiliation(s)
- Nathan P Manes
- Cellular Networks Proteomics Unit, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health
| | - Jessica M Mann
- Cellular Networks Proteomics Unit, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health
| | - Aleksandra Nita-Lazar
- Cellular Networks Proteomics Unit, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health;
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