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Douillard FP, Portinha IM, Derman Y, Woudstra C, Mäklin T, Dorner MB, Korkeala H, Henriques AO, Lindström M. A Novel Prophage-like Insertion Element within yabG Triggers Early Entry into Sporulation in Clostridium botulinum. Viruses 2023; 15:2431. [PMID: 38140671 PMCID: PMC10747680 DOI: 10.3390/v15122431] [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: 05/25/2023] [Revised: 12/12/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023] Open
Abstract
Sporulation is a finely regulated morphogenetic program important in the ecology and epidemiology of Clostridium botulinum. Exogenous elements disrupting sporulation-associated genes contribute to sporulation regulation and introduce diversity in the generally conserved sporulation programs of endospore formers. We identified a novel prophage-like DNA segment, termed the yin element, inserted within yabG, encoding a sporulation-specific cysteine protease, in an environmental isolate of C. botulinum. Bioinformatic analysis revealed that the genetic structure of the yin element resembles previously reported mobile intervening elements associated with sporulation genes. Within a pure C. botulinum culture, we observed two subpopulations of cells with the yin element either integrated into the yabG locus or excised as a circular DNA molecule. The dynamics between the two observed conformations of the yin element was growth-phase dependent and likely mediated by recombination events. The yin element was not required for sporulation by C. botulinum but triggered an earlier entry into sporulation than in a related isolate lacking this element. So far, the yin element has not been found in any other C. botulinum strains or other endospore-forming species. It remains to be demonstrated what kind of competitive edge it provides for C. botulinum survival and persistence.
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Affiliation(s)
- François P. Douillard
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, 00350 Helsinki, Finland; (F.P.D.); (I.M.P.); (Y.D.); (C.W.); (H.K.)
| | - Inês Martins Portinha
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, 00350 Helsinki, Finland; (F.P.D.); (I.M.P.); (Y.D.); (C.W.); (H.K.)
| | - Yağmur Derman
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, 00350 Helsinki, Finland; (F.P.D.); (I.M.P.); (Y.D.); (C.W.); (H.K.)
| | - Cédric Woudstra
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, 00350 Helsinki, Finland; (F.P.D.); (I.M.P.); (Y.D.); (C.W.); (H.K.)
| | - Tommi Mäklin
- Department of Mathematics and Statistics, Faculty of Science, University of Helsinki, 00560 Helsinki, Finland;
| | - Martin B. Dorner
- Centre for Biological Threats and Special Pathogens, ZBS3—Biological Toxins, Robert Koch Institute, 13353 Berlin, Germany;
| | - Hannu Korkeala
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, 00350 Helsinki, Finland; (F.P.D.); (I.M.P.); (Y.D.); (C.W.); (H.K.)
| | - Adriano O. Henriques
- Institute of Chemical and Biological Technology, NOVA University Lisbon, 2780-157 Oeiras, Portugal;
| | - Miia Lindström
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, 00350 Helsinki, Finland; (F.P.D.); (I.M.P.); (Y.D.); (C.W.); (H.K.)
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Hendrickx D, Varela Martínez C, Contzen M, Wagner-Wiening C, Janke KH, Hernando Jiménez P, Massing S, Pichler J, Tichaczek-Dischinger P, Burckhardt F, Stark K, Katz K, Jurke A, Thole S, Carbó R, del Pobil Ferré MP, Nieto M, Zamora MJ, Sisó A, Pallares García P, Valdezate S, Schaade L, Worbs S, Dorner BG, Frank C, Dorner MB. First cross-border outbreak of foodborne botulism in the European Union associated with the consumption of commercial dried roach ( Rutilus rutilus). Front Public Health 2023; 10:1039770. [PMID: 36684858 PMCID: PMC9846170 DOI: 10.3389/fpubh.2022.1039770] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 12/05/2022] [Indexed: 01/05/2023] Open
Abstract
Botulism outbreaks due to commercial products are extremely rare in the European Union. Here we report on the first international outbreak of foodborne botulism caused by commercial salt-cured, dried roach (Rutilus rutilus). Between November and December 2016, an outbreak of six foodborne botulism type E cases from five unrelated households was documented in Germany and Spain. The outbreak involved persons of Russian and Kazakh backgrounds, all consumed unheated salt-cured, dried roach-a snack particularly favored in Easter-European countries. The implicated food batches had been distributed by an international wholesaler and were recalled from Europe-wide outlets of a supermarket chain and other independent retailers. Of interest, and very unlike to other foodborne disease outbreaks which usually involves a single strain or virus variant, different Clostridium botulinum strains and toxin variants could be identified even from a single patient's sample. Foodborne botulism is a rare but potentially life-threatening disease and almost exclusively involves home-made or artisan products and thus, outbreaks are limited to individual or few cases. As a consequence, international outbreaks are the absolute exception and this is the first one within the European Union. Additional cases were likely prevented by a broad product recall, underscoring the importance of timely public health action. Challenges and difficulties on the diagnostic and epidemiological level encountered in the outbreak are highlighted.
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Affiliation(s)
- David Hendrickx
- Landesgesundheitsamt Baden-Württemberg, Ministerium für Soziales, Gesundheit und Integration Baden-Württemberg, Stuttgart, Germany
- European Centre for Disease Prevention and Control, European Programme for Intervention Epidemiology Training (EPIET), Stockholm, Sweden
| | - Carmen Varela Martínez
- National Centre of Epidemiology, Institute of Health Carlos III, Madrid, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Institute of Health Carlos III, Madrid, Spain
| | - Matthias Contzen
- Chemisches und Veterinäruntersuchungsamt Stuttgart, Ministerium für Ernährung, Ländlichen Raum und Verbraucherschutz Baden-Württemberg, Fellbach, Germany
| | - Christiane Wagner-Wiening
- Landesgesundheitsamt Baden-Württemberg, Ministerium für Soziales, Gesundheit und Integration Baden-Württemberg, Stuttgart, Germany
| | - Karl-Heinz Janke
- Landesgesundheitsamt Baden-Württemberg, Ministerium für Soziales, Gesundheit und Integration Baden-Württemberg, Stuttgart, Germany
| | - Pablo Hernando Jiménez
- Chemisches und Veterinäruntersuchungsamt Karlsruhe, Ministerium für Ernährung, Ländlichen Raum und Verbraucherschutz Baden Württemberg, Karlsruhe, Germany
| | - Susanne Massing
- Landratsamt Böblingen, Veterinärdienst und Lebensmittelüberwachung, Böblingen, Germany
| | | | - Petra Tichaczek-Dischinger
- Chemisches und Veterinäruntersuchungsamt Stuttgart, Ministerium für Ernährung, Ländlichen Raum und Verbraucherschutz Baden-Württemberg, Fellbach, Germany
| | - Florian Burckhardt
- Landesuntersuchungsamt Rheinland-Pfalz, Rhineland-Palatinate, Koblenz, Germany
| | - Klaus Stark
- Department for Infectious Disease Epidemiology, Robert Koch Institute, Berlin, Germany
| | - Katharina Katz
- GE 2.3 Epidemiologie übertragbarer Krankheiten, Landesamt für Gesundheit und Lebensmittelsicherheit, Oberschleißheim, Germany
| | - Annette Jurke
- Landeszentrum Gesundheit Nordrhein-Westfalen, North Rhine-Westphalia, Bochum, Germany
| | - Sebastian Thole
- Landeszentrum Gesundheit Nordrhein-Westfalen, North Rhine-Westphalia, Bochum, Germany
| | - Rosa Carbó
- Servicio de Vigilancia y Control Epidemiológico, Dirección General de Salud Pública, Valencia, Spain
| | | | - Milagros Nieto
- National Food Centre (CNA), Spanish Agency for Consumer Affairs Food Safety (AESAN), Majadahonda, Spain
| | - María Jesús Zamora
- National Food Centre (CNA), Spanish Agency for Consumer Affairs Food Safety (AESAN), Majadahonda, Spain
| | - Ana Sisó
- National Food Centre (CNA), Spanish Agency for Consumer Affairs Food Safety (AESAN), Majadahonda, Spain
| | | | - Sylvia Valdezate
- National Centre of Microbiology, Institute of Health Carlos III, Madrid, Spain
| | - Lars Schaade
- Consultant Laboratory for Neurotoxin-Producing Clostridia (Botulism, Tetanus), Robert Koch Institute, Berlin, Germany
| | - Sylvia Worbs
- Consultant Laboratory for Neurotoxin-Producing Clostridia (Botulism, Tetanus), Robert Koch Institute, Berlin, Germany
| | - Brigitte Gertrud Dorner
- Consultant Laboratory for Neurotoxin-Producing Clostridia (Botulism, Tetanus), Robert Koch Institute, Berlin, Germany
| | - Christina Frank
- Landesuntersuchungsamt Rheinland-Pfalz, Rhineland-Palatinate, Koblenz, Germany
| | - Martin Bernhard Dorner
- Consultant Laboratory for Neurotoxin-Producing Clostridia (Botulism, Tetanus), Robert Koch Institute, Berlin, Germany
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Affiliation(s)
- Pankaj Kumar
- Nano-Bioconjugate Chemistry Lab, Cluster Innovation Centre, University of Delhi, Delhi - 110007, India
- Department of Chemistry, University of Delhi, Delhi - 110007, India
| | - Niloy Sarkar
- Nano-Bioconjugate Chemistry Lab, Cluster Innovation Centre, University of Delhi, Delhi - 110007, India
- Department of Environmental Studies, University of Delhi, Delhi - 110007, India
| | - Amit Singh
- Nano-Bioconjugate Chemistry Lab, Cluster Innovation Centre, University of Delhi, Delhi - 110007, India
- Department of Chemistry, University of Delhi, Delhi - 110007, India
| | - Mahima Kaushik
- Nano-Bioconjugate Chemistry Lab, Cluster Innovation Centre, University of Delhi, Delhi - 110007, India
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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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Genomic and Phenotypic Characterization of Clostridium botulinum Isolates from an Infant Botulism Case Suggests Adaptation Signatures to the Gut. mBio 2022; 13:e0238421. [PMID: 35499308 PMCID: PMC9239077 DOI: 10.1128/mbio.02384-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
In early life, the immature human gut microbiota is prone to colonization by pathogens that are usually outcompeted by mature microbiota in the adult gut. Colonization and neurotoxin production by a vegetative Clostridium botulinum culture in the gut of an infant can lead to flaccid paralysis, resulting in a clinical outcome known as infant botulism, a potentially life-threatening condition. Beside host factors, little is known of the ecology, colonization, and adaptation of C. botulinum to the gut environment. In our previous report, an infant with intestinal botulism was shown to be colonized by neurotoxigenic C. botulinum culture for 7 months. In an effort to gain ecological and evolutionary insights into this unusually long gut colonization by C. botulinum, we analyzed and compared the genomes of C. botulinum isolates recovered from the infant feces during the course of intoxication and isolates from the infant household dust. A number of observed mutations and genomic alterations pinpointed at phenotypic traits that may have promoted colonization and adaptation to the gut environment and to the host. These traits include motility, quorum-sensing, sporulation, and carbohydrate metabolism. We provide novel perspectives and suggest a tentative model of the pathogenesis of C. botulinum in infant botulism.
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Nowakowska MB, Selby K, Przykopanski A, Krüger M, Krez N, Dorner BG, Dorner MB, Jin R, Minton NP, Rummel A, Lindström M. Construction and validation of safe Clostridium botulinum Group II surrogate strain producing inactive botulinum neurotoxin type E toxoid. Sci Rep 2022; 12:1790. [PMID: 35110559 PMCID: PMC8810926 DOI: 10.1038/s41598-022-05008-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 12/24/2021] [Indexed: 01/05/2023] Open
Abstract
Botulinum neurotoxins (BoNTs), produced by the spore-forming bacterium Clostridium botulinum, cause botulism, a rare but fatal illness affecting humans and animals. Despite causing a life-threatening disease, BoNT is a multipurpose therapeutic. Nevertheless, as the most potent natural toxin, BoNT is classified as a Select Agent in the US, placing C. botulinum research under stringent governmental regulations. The extreme toxicity of BoNT, its impact on public safety, and its diverse therapeutic applications urge to devise safe solutions to expand C. botulinum research. Accordingly, we exploited CRISPR/Cas9-mediated genome editing to introduce inactivating point mutations into chromosomal bont/e gene of C. botulinum Beluga E. The resulting Beluga Ei strain displays unchanged physiology and produces inactive BoNT (BoNT/Ei) recognized in serological assays, but lacking biological activity detectable ex- and in vivo. Neither native single-chain, nor trypsinized di-chain form of BoNT/Ei show in vivo toxicity, even if isolated from Beluga Ei sub-cultured for 25 generations. Beluga Ei strain constitutes a safe alternative for the BoNT research necessary for public health risk management, the development of food preservation strategies, understanding toxinogenesis, and for structural BoNT studies. The example of Beluga Ei generation serves as template for future development of C. botulinum producing different inactive BoNT serotypes.
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Affiliation(s)
- Maria B Nowakowska
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Katja Selby
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Adina Przykopanski
- Institut Für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Maren Krüger
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Nadja Krez
- Institut Für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Brigitte G Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Martin B Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Rongsheng Jin
- Department of Physiology and Biophysics, University of California, Irvine, CA, USA
| | - Nigel P Minton
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, Biodiscovery Institute, University of Nottingham, Nottingham, UK
| | - Andreas Rummel
- Institut Für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Miia Lindström
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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Neeki MM, Dong F, Emond C, Lee C, Neeki AS, Hajjafar K, Messinger M, Anderson CO, Hajjafar R, Borger R. Early diagnosis and critical management of wound botulism in the emergency department: a single center experience and literature review. Int J Emerg Med 2021; 14:56. [PMID: 34551726 PMCID: PMC8456643 DOI: 10.1186/s12245-021-00375-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 08/27/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Clostridium botulinum remains a major threat to a select population of subcutaneous and intramuscular drug users. We conducted a retrospective study of patients who were diagnosed with wound botulism and their clinical presentations to the Emergency Department (ED). RESULTS A total of 21 patients met the inclusion criteria and all had a confirmed history of heroin use disorder. Initial presentation to the ED included generalized weakness (n = 20, 95%), difficulty swallowing (n = 15, 71%), and speech/voice problems (n = 14, 79%). Sixteen patients (76%) also presented with visible skin wounds and fifteen (71%) required mechanical ventilation (MV). Patients who presented with dysphagia as well as dysarthria and/or dysphonia were more likely to require a percutaneous endoscopic gastrostomy (PEG) tube. Patients who required MV and PEG tubes were noted to have a longer hospital length of stay (LOS) due to the severity of the disease progression. CONCLUSIONS Emergency physicians should remain vigilant about early recognition of wound botulism, especially in patients who inject drugs.
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Affiliation(s)
- Michael M Neeki
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA. .,California University of Science and Medicine, San Bernardino, CA, 92324, USA.
| | - Fanlong Dong
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA
| | - Chuck Emond
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA
| | - Carol Lee
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA.,California University of Science and Medicine, San Bernardino, CA, 92324, USA
| | - Arianna S Neeki
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA
| | - Keeyon Hajjafar
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA
| | - Megan Messinger
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA
| | - Caitlyn O Anderson
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA
| | - Reza Hajjafar
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA
| | - Rodney Borger
- Department of Emergency Medicine, Arrowhead Regional Medical Center, 400 N. Pepper Ave, Suite # 107, Colton, CA, 92324, USA.,California University of Science and Medicine, San Bernardino, CA, 92324, USA
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Masters AM, Palmer DG. Confirmation of botulism diagnosis in Australian bird samples by ELISA and RT rtPCR. J Vet Diagn Invest 2021; 33:684-694. [PMID: 33955287 DOI: 10.1177/10406387211014486] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We developed a sandwich ELISA that detects Clostridium botulinum C and D toxins and reverse-transcription real-time PCRs (RT-rtPCRs) that detect botulinum C and D toxin genes, respectively, to replace the mouse bioassay. The toxin genes were closely associated with the toxin molecules and used as surrogates for the presence of toxin. Samples (638) from 103 clinical cases of birds (302) with suspected botulinum toxicity came from wild birds and poultry (9 cases). Samples tested included blood serum, other body fluids, various tissues, gut contents, maggots, water, and sediment. Botulism was diagnosed in 34 cases (all of which had positive samples in the ELISA, the C toxin gene RT-rtPCR, or both assays). Botulism was suspected in 16 cases (each of which had 1 positive sample either in the ELISA or the C toxin gene RT-rtPCR). In the remaining 53 cases, no samples were positive, but botulism could not be excluded in 32 of these cases, whereas there was no indication of botulism or another diagnosis in 21 cases. The D toxin gene was not detected in any of the clinical samples. No C or D toxin genes were detected in 71 pooled cloacal swabs from 213 healthy migratory birds. The use of an ELISA that detects botulinum C and D toxins in combination with a RT-rtPCR for the botulinum C toxin gene can help confirm the diagnosis of botulism in birds.
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Affiliation(s)
- Anne M Masters
- DPIRD Diagnostics & Laboratory Services, Department of Primary Industries and Regional Development Western Australia, South Perth, Australia
| | - Dieter G Palmer
- DPIRD Diagnostics & Laboratory Services, Department of Primary Industries and Regional Development Western Australia, South Perth, Australia
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Tevell Åberg A, Karlsson I, Hedeland M. Modification and validation of the Endopep-mass spectrometry method for botulinum neurotoxin detection in liver samples with application to samples collected during animal botulism outbreaks. Anal Bioanal Chem 2020; 413:345-354. [PMID: 33119784 PMCID: PMC7806574 DOI: 10.1007/s00216-020-03001-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/29/2020] [Accepted: 10/09/2020] [Indexed: 01/07/2023]
Abstract
Botulinum neurotoxins (BoNTs) are the most potent toxins known and they cause the paralytic disease botulism in humans and animals. In order to diagnose botulism, active BoNT must be detected in biological material. Endopep-MS is a sensitive and selective method for serum samples, based on antibody capture, enzymatic cleavage of target peptides, and detection of cleavage products using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). In many cases of animal botulism, serum samples are not available or they do not contain detectable amounts of BoNT and liver sampling is an alternative for postmortem examinations. However, the Endopep-MS method is impaired by the inherent protease activity of liver samples. In the presented study, the Endopep-MS method has been successfully modified and validated for analysis of cattle, horse, and avian liver samples, introducing a combination of a salt washing step and a protease inhibitor cocktail. These modifications resulted in a substantial decrease in interfering signals and increase in BoNT-specific signals. This led to a substantial improvement in sensitivity for especially BoNT-C and C/D which are among the most prominent serotypes for animal botulism. Botulism was diagnosed with the new method in liver samples from dead cattle and birds from outbreaks in Sweden. Graphical Abstract.
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Affiliation(s)
- Annica Tevell Åberg
- Department of Chemistry, Environment, and Feed Hygiene, National Veterinary Institute (SVA), 751 89, Uppsala, Sweden.,Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Faculty of Pharmacy, Uppsala University, P.O. Box 574, 751 23, Uppsala, Sweden
| | - Ida Karlsson
- Department of Chemistry, Environment, and Feed Hygiene, National Veterinary Institute (SVA), 751 89, Uppsala, Sweden.,Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Faculty of Pharmacy, Uppsala University, P.O. Box 574, 751 23, Uppsala, Sweden
| | - Mikael Hedeland
- Department of Chemistry, Environment, and Feed Hygiene, National Veterinary Institute (SVA), 751 89, Uppsala, Sweden. .,Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Faculty of Pharmacy, Uppsala University, P.O. Box 574, 751 23, Uppsala, Sweden.
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10
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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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11
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Pellett S, Tepp WH, Johnson EA. Critical Analysis of Neuronal Cell and the Mouse Bioassay for Detection of Botulinum Neurotoxins. Toxins (Basel) 2019; 11:E713. [PMID: 31817843 PMCID: PMC6950160 DOI: 10.3390/toxins11120713] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/12/2019] [Accepted: 11/22/2019] [Indexed: 12/14/2022] Open
Abstract
Botulinum Neurotoxins (BoNTs) are a large protein family that includes the most potent neurotoxins known to humankind. BoNTs delivered locally in humans at low doses are widely used pharmaceuticals. Reliable and quantitative detection of BoNTs is of paramount importance for the clinical diagnosis of botulism, basic research, drug development, potency determination, and detection in clinical, environmental, and food samples. Ideally, a definitive assay for BoNT should reflect the activity of each of the four steps in nerve intoxication. The in vivo mouse bioassay (MBA) is the 'gold standard' for the detection of BoNTs. The MBA is sensitive, robust, semi-quantitative, and reliable within its sensitivity limits. Potential drawbacks with the MBA include assay-to-assay potency variations, especially between laboratories, and false positives or negatives. These limitations can be largely avoided by careful planning and performance. Another detection method that has gained importance in recent years for research and potency determination of pharmaceutical BoNTs is cell-based assays, as these assays can be highly sensitive, quantitative, human-specific, and detect fully functional holotoxins at physiologically relevant concentrations. A myriad of other in vitro BoNT detection methods exist. This review focuses on critical factors and assay limitations of the mouse bioassay and cell-based assays for BoNT detection.
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Affiliation(s)
| | | | - Eric A. Johnson
- Department of Bacteriology, University of Wisconsin-Madison, 1550 Linden Dr, Madison, WI 53706, USA; (S.P.); (W.H.T.)
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12
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Wang C, Xiao R, Wang S, Yang X, Bai Z, Li X, Rong Z, Shen B, Wang S. Magnetic quantum dot based lateral flow assay biosensor for multiplex and sensitive detection of protein toxins in food samples. Biosens Bioelectron 2019; 146:111754. [PMID: 31605985 DOI: 10.1016/j.bios.2019.111754] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/20/2019] [Accepted: 09/30/2019] [Indexed: 01/09/2023]
Abstract
Protein toxins, such as botulinum neurotoxin type A (BoNT/A) and staphylococcal enterotoxin B (SEB), easily pollute food and water and are ultra-toxic to humans and animals, thus requiring a sensitive on-site detection method. In this study, we reported a novel lateral flow assay (LFA) strip on the basis of magnetic quantum dot nanoparticles (MagQD NPs) for sensitive and multiplex protein toxin detection in food samples. A new type of MagQD NP was prepared by fixing the dense carboxylated QDs on the surface of polyethyleneimine-modified Fe3O4 magnetic NPs (MNPs) and applied in LFA with the following functions: capture and enrich target toxins from sample solutions and serve as advanced fluorescent labels for the quantitative determination of targets on the strip. Through this strategy, the assay realized quantified BoNT/A and SEB detection in 30 min with the limits of detection of 2.52 and 2.86 pg/mL, respectively. The selectivity and the ability of quantitative analysis of the method were validated in real food samples, including milk and juice. This MagQD-LFA biosensor showed considerable potential as a point-of-care testing tool for the sensitive detection of trace toxins.
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Affiliation(s)
- Chongwen Wang
- College of Life Sciences, Anhui Agricultural University, Hefei, 230036, PR China; Beijing Institute of Radiation Medicine, Beijing, 100850, PR China; Beijing Key Laboratory of New Molecular Diagnosis Technologies for Infectious Diseases, Beijing, 100850, PR China
| | - Rui Xiao
- Beijing Institute of Radiation Medicine, Beijing, 100850, PR China; Beijing Key Laboratory of New Molecular Diagnosis Technologies for Infectious Diseases, Beijing, 100850, PR China
| | - Shu Wang
- College of Life Sciences, Anhui Agricultural University, Hefei, 230036, PR China; Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei, PR China
| | - Xingsheng Yang
- College of Life Sciences, Anhui Agricultural University, Hefei, 230036, PR China
| | - Zikun Bai
- Beijing Institute of Radiation Medicine, Beijing, 100850, PR China
| | - Xinying Li
- Institute of Basic Medical Sciences, Beijing, 100850, PR China
| | - Zhen Rong
- Beijing Institute of Radiation Medicine, Beijing, 100850, PR China; Beijing Key Laboratory of New Molecular Diagnosis Technologies for Infectious Diseases, Beijing, 100850, PR China.
| | - Beifen Shen
- Institute of Basic Medical Sciences, Beijing, 100850, PR China.
| | - Shengqi Wang
- College of Life Sciences, Anhui Agricultural University, Hefei, 230036, PR China; Beijing Institute of Radiation Medicine, Beijing, 100850, PR China; Beijing Key Laboratory of New Molecular Diagnosis Technologies for Infectious Diseases, Beijing, 100850, PR China.
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13
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von Berg L, Stern D, Pauly D, Mahrhold S, Weisemann J, Jentsch L, Hansbauer EM, Müller C, Avondet MA, Rummel A, Dorner MB, Dorner BG. Functional detection of botulinum neurotoxin serotypes A to F by monoclonal neoepitope-specific antibodies and suspension array technology. Sci Rep 2019; 9:5531. [PMID: 30940836 PMCID: PMC6445094 DOI: 10.1038/s41598-019-41722-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 03/15/2019] [Indexed: 12/26/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are the most potent toxins known and cause the life threatening disease botulism. Sensitive and broad detection is extremely challenging due to the toxins' high potency and molecular heterogeneity with several serotypes and more than 40 subtypes. The toxicity of BoNT is mediated by enzymatic cleavage of different synaptic proteins involved in neurotransmitter release at serotype-specific cleavage sites. Hence, active BoNTs can be monitored and distinguished in vitro by detecting their substrate cleavage products. In this work, we developed a comprehensive panel of monoclonal neoepitope antibodies (Neo-mAbs) highly specific for the newly generated N- and/or C-termini of the substrate cleavage products of BoNT serotypes A to F. The Neo-mAbs were implemented in a set of three enzymatic assays for the simultaneous detection of two BoNT serotypes each by monitoring substrate cleavage on colour-coded magnetic Luminex-beads. For the first time, all relevant serotypes could be detected in parallel by a routine in vitro activity assay in spiked serum and food samples yielding excellent detection limits in the range of the mouse bioassay or better (0.3-80 pg/mL). Therefore, this work represents a major step towards the replacement of the mouse bioassay for botulism diagnostics.
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Affiliation(s)
- Laura von Berg
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, 13353, Germany
| | - Daniel Stern
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, 13353, Germany
| | - Diana Pauly
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, 13353, Germany
- Department of Ophthalmology, University Hospital Regensburg, Regensburg, 93053, Germany
| | - Stefan Mahrhold
- Institut für Toxikologie, Medizinische Hochschule Hannover, 30625, Hannover, Germany
| | - Jasmin Weisemann
- Institut für Toxikologie, Medizinische Hochschule Hannover, 30625, Hannover, Germany
| | - Lisa Jentsch
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, 13353, Germany
| | - Eva-Maria Hansbauer
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, 13353, Germany
| | - Christian Müller
- Spiez Laboratory, Federal Office for Civil Protection, Spiez, 3700, Switzerland
| | - Marc A Avondet
- Spiez Laboratory, Federal Office for Civil Protection, Spiez, 3700, Switzerland
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, 30625, Hannover, Germany
| | - Martin B Dorner
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, 13353, Germany
| | - Brigitte G Dorner
- Biological Toxins (ZBS 3), Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, 13353, Germany.
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14
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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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15
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Mad'arová L, Dorner BG, Schaade L, Donáth V, Avdičová M, Fatkulinová M, Strhársky J, Sedliačiková I, Klement C, Dorner MB. Reoccurrence of botulinum neurotoxin subtype A3 inducing food-borne botulism, Slovakia, 2015. ACTA ACUST UNITED AC 2017; 22:30591. [PMID: 28816652 PMCID: PMC6373608 DOI: 10.2807/1560-7917.es.2017.22.32.30591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 11/25/2016] [Indexed: 01/10/2023]
Abstract
A case of food-borne botulism occurred in Slovakia in 2015. Clostridium botulinum type A was isolated from three nearly empty commercial hummus tubes. The product, which was sold in Slovakia and the Czech Republic, was withdrawn from the market and a warning was issued immediately through the European Commission's Rapid Alert System for Food and Feed (RASFF). Further investigation revealed the presence of botulinum neurotoxin (BoNT) subtype BoNT/A3, a very rare subtype implicated in only one previous outbreak (Loch Maree in Scotland, 1922). It is the most divergent subtype of BoNT/A with 15.4% difference at the amino acid level compared with the prototype BoNT/A1. This makes it more prone to evading immunological and PCR-based detection. It is recommended that testing laboratories are advised that this subtype has been associated with food-borne botulism for the second time since the first outbreak almost 100 years ago, and to validate their immunological or PCR-based methods against this divergent subtype.
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Affiliation(s)
- Lucia Mad'arová
- Regional Authority of Public Health Banská Bystrica, Banská Bystrica, Slovakia
| | - Brigitte G Dorner
- Robert Koch Institute, Consultant laboratory for neurotoxin-producing clostridia (botulism, tetanus), Berlin, Germany.,Robert Koch Institute, Centre for Biological Threats and Special Pathogens, Berlin, Germany
| | - Lars Schaade
- Robert Koch Institute, Centre for Biological Threats and Special Pathogens, Berlin, Germany
| | - Vladimír Donáth
- F. D. Roosevelt Teaching Hospital, Department of Neurology, Slovak Medical University, Banská Bystrica, Slovakia
| | - Mária Avdičová
- Regional Authority of Public Health Banská Bystrica, Banská Bystrica, Slovakia
| | - Milota Fatkulinová
- Regional Authority of Public Health Banská Bystrica, Banská Bystrica, Slovakia
| | - Jozef Strhársky
- Regional Authority of Public Health Banská Bystrica, Banská Bystrica, Slovakia
| | - Ivana Sedliačiková
- Regional Authority of Public Health Banská Bystrica, Banská Bystrica, Slovakia
| | - Cyril Klement
- Regional Authority of Public Health Banská Bystrica, Banská Bystrica, Slovakia.,Slovak Medical University, Faculty of Public Health, Bratislava, Slovakia
| | - Martin B Dorner
- Robert Koch Institute, Consultant laboratory for neurotoxin-producing clostridia (botulism, tetanus), Berlin, Germany.,Robert Koch Institute, Centre for Biological Threats and Special Pathogens, Berlin, Germany
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16
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Yadirgi G, Stickings P, Rajagopal S, Liu Y, Sesardic D. Immuno-detection of cleaved SNAP-25 from differentiated mouse embryonic stem cells provides a sensitive assay for determination of botulinum A toxin and antitoxin potency. J Immunol Methods 2017; 451:90-99. [PMID: 28943257 DOI: 10.1016/j.jim.2017.09.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/19/2017] [Accepted: 09/20/2017] [Indexed: 01/12/2023]
Abstract
Botulinum toxin type A is a causative agent of human botulism. Due to high toxicity and ease of production it is classified by the Centres for Disease Control and Prevention as a category A bioterrorism agent. The same serotype, BoNT/A, is also the most widely used in pharmaceutical preparations for treatment of a diverse range of neuromuscular disorders. Traditionally, animals are used to confirm the presence and activity of toxin and to establish neutralizing capabilities of countermeasures in toxin neutralization tests. Cell based assays for BoNT/A have been reported as the most viable alternative to animal models, since they are capable of reflecting all key steps (binding, translocation, internalization and cleavage of intracellular substrate) involved in toxin activity. In this paper we report preliminary development of a simple immunochemical method for specifically detecting BoNT/A cleaved intracellular substrate, SNAP-25, in cell lysates of neurons derived from mouse embryonic stem cells. The assay offers sensitivity of better than 0.1LD50/ml (3fM) which is not matched by other functional assays, including the mouse bioassay, and provides serotype specificity for quantitative detection of BoNT/A and anti-BoNT/A antitoxin. Subject to formal validation, the method described here could potentially be used as a substitute for the mouse bioassay to measure potency and consistency of therapeutic products.
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Affiliation(s)
- G Yadirgi
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - P Stickings
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - S Rajagopal
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - Y Liu
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - D Sesardic
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
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17
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Biological toxins of potential bioterrorism risk: Current status of detection and identification technology. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2016.05.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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18
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Worbs S, Skiba M, Söderström M, Rapinoja ML, Zeleny R, Russmann H, Schimmel H, Vanninen P, Fredriksson SÅ, Dorner BG. Characterization of Ricin and R. communis Agglutinin Reference Materials. Toxins (Basel) 2015; 7:4906-34. [PMID: 26703723 PMCID: PMC4690106 DOI: 10.3390/toxins7124856] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 10/07/2015] [Accepted: 10/22/2015] [Indexed: 12/12/2022] Open
Abstract
Ricinus communis intoxications have been known for centuries and were attributed to the toxic protein ricin. Due to its toxicity, availability, ease of preparation, and the lack of medical countermeasures, ricin attracted interest as a potential biological warfare agent. While different technologies for ricin analysis have been established, hardly any universally agreed-upon "gold standards" are available. Expert laboratories currently use differently purified in-house materials, making any comparison of accuracy and sensitivity of different methods nearly impossible. Technically challenging is the discrimination of ricin from R. communis agglutinin (RCA120), a less toxic but highly homologous protein also contained in R. communis. Here, we established both highly pure ricin and RCA120 reference materials which were extensively characterized by gel electrophoresis, liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI MS/MS), and matrix-assisted laser desorption ionization-time of flight approaches as well as immunological and functional techniques. Purity reached >97% for ricin and >99% for RCA120. Different isoforms of ricin and RCA120 were identified unambiguously and distinguished by LC-ESI MS/MS. In terms of function, a real-time cytotoxicity assay showed that ricin is approximately 300-fold more toxic than RCA120. The highly pure ricin and RCA120 reference materials were used to conduct an international proficiency test.
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Affiliation(s)
- Sylvia Worbs
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Martin Skiba
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Martin Söderström
- VERIFIN (Finnish Institute for Verification of the ChemicalWeapons Convention), Department of Chemistry, University of Helsinki, A.I. Virtasen aukio 1, Helsinki 05600, Finland.
| | - Marja-Leena Rapinoja
- VERIFIN (Finnish Institute for Verification of the ChemicalWeapons Convention), Department of Chemistry, University of Helsinki, A.I. Virtasen aukio 1, Helsinki 05600, Finland.
| | - Reinhard Zeleny
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440 Geel, Belgium.
| | - Heiko Russmann
- Bundeswehr Research Institute for Protective Technologies and NBC Protection, Humboldtstr. 100, 29633 Munster, Germany.
| | - Heinz Schimmel
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440 Geel, Belgium.
| | - Paula Vanninen
- VERIFIN (Finnish Institute for Verification of the ChemicalWeapons Convention), Department of Chemistry, University of Helsinki, A.I. Virtasen aukio 1, Helsinki 05600, Finland.
| | - Sten-Åke Fredriksson
- FOI, Swedish Defence Research Agency, CBRN Defence and Security, Cementvagen 20, 901 82 Umeå, Sweden.
| | - Brigitte G Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
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19
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Weisemann J, Krez N, Fiebig U, Worbs S, Skiba M, Endermann T, Dorner MB, Bergström T, Muñoz A, Zegers I, Müller C, Jenkinson SP, Avondet MA, Delbrassinne L, Denayer S, Zeleny R, Schimmel H, Åstot C, Dorner BG, Rummel A. Generation and Characterization of Six Recombinant Botulinum Neurotoxins as Reference Material to Serve in an International Proficiency Test. Toxins (Basel) 2015; 7:5035-54. [PMID: 26703728 PMCID: PMC4690111 DOI: 10.3390/toxins7124861] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 11/10/2015] [Accepted: 11/13/2015] [Indexed: 12/22/2022] Open
Abstract
The detection and identification of botulinum neurotoxins (BoNT) is complex due to the existence of seven serotypes, derived mosaic toxins and more than 40 subtypes. Expert laboratories currently use different technical approaches to detect, identify and quantify BoNT, but due to the lack of (certified) reference materials, analytical results can hardly be compared. In this study, the six BoNT/A1–F1 prototypes were successfully produced by recombinant techniques, facilitating handling, as well as improving purity, yield, reproducibility and biosafety. All six BoNTs were quantitatively nicked into active di-chain toxins linked by a disulfide bridge. The materials were thoroughly characterized with respect to purity, identity, protein concentration, catalytic and biological activities. For BoNT/A1, B1 and E1, serotypes pathogenic to humans, the catalytic activity and the precise protein concentration were determined by Endopep-mass spectrometry and validated amino acid analysis, respectively. In addition, BoNT/A1, B1, E1 and F1 were successfully detected by immunological assays, unambiguously identified by mass spectrometric-based methods, and their specific activities were assigned by the mouse LD50 bioassay. The potencies of all six BoNT/A1–F1 were quantified by the ex vivo mouse phrenic nerve hemidiaphragm assay, allowing a direct comparison. In conclusion, highly pure recombinant BoNT reference materials were produced, thoroughly characterized and employed as spiking material in a worldwide BoNT proficiency test organized by the EQuATox consortium.
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Affiliation(s)
| | - Nadja Krez
- Toxogen GmbH, Feodor-Lynen-Str. 35, 30625 Hannover, Germany.
| | - Uwe Fiebig
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Sylvia Worbs
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Martin Skiba
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Tanja Endermann
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Martin B Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Tomas Bergström
- Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Cementvägen 20, 90182 Umeå, Sweden.
| | - Amalia Muñoz
- Joint Research Centre, Institute for Reference Materials and Measurements, European Commission, Retieseweg 111, 2440 Geel, Belgium.
| | - Ingrid Zegers
- Joint Research Centre, Institute for Reference Materials and Measurements, European Commission, Retieseweg 111, 2440 Geel, Belgium.
| | - Christian Müller
- Federal Department of Defence, Civil Protection and Sport-Spiez Laboratory, Austrasse 1, 3700 Spiez, Switzerland.
| | - Stephen P Jenkinson
- Federal Department of Defence, Civil Protection and Sport-Spiez Laboratory, Austrasse 1, 3700 Spiez, Switzerland.
| | - Marc-Andre Avondet
- Federal Department of Defence, Civil Protection and Sport-Spiez Laboratory, Austrasse 1, 3700 Spiez, Switzerland.
| | - Laurence Delbrassinne
- Scientific Service of Food-Borne Pathogens, Operational Directorate of Communicable and Infectious Diseases, Scientific Institute of Public Health (WIV-ISP), 1050 Brussels, Belgium.
| | - Sarah Denayer
- Scientific Service of Food-Borne Pathogens, Operational Directorate of Communicable and Infectious Diseases, Scientific Institute of Public Health (WIV-ISP), 1050 Brussels, Belgium.
| | - Reinhard Zeleny
- Joint Research Centre, Institute for Reference Materials and Measurements, European Commission, Retieseweg 111, 2440 Geel, Belgium.
| | - Heinz Schimmel
- Joint Research Centre, Institute for Reference Materials and Measurements, European Commission, Retieseweg 111, 2440 Geel, Belgium.
| | - Crister Åstot
- Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Cementvägen 20, 90182 Umeå, Sweden.
| | - Brigitte G Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestr. 10, 13353 Berlin, Germany.
| | - Andreas Rummel
- Toxogen GmbH, Feodor-Lynen-Str. 35, 30625 Hannover, Germany.
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20
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Worbs S, Fiebig U, Zeleny R, Schimmel H, Rummel A, Luginbühl W, Dorner BG. Qualitative and Quantitative Detection of Botulinum Neurotoxins from Complex Matrices: Results of the First International Proficiency Test. Toxins (Basel) 2015; 7:4935-66. [PMID: 26703724 PMCID: PMC4690107 DOI: 10.3390/toxins7124857] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 11/03/2015] [Accepted: 11/05/2015] [Indexed: 11/16/2022] Open
Abstract
In the framework of the EU project EQuATox, a first international proficiency test (PT) on the detection and quantification of botulinum neurotoxins (BoNT) was conducted. Sample materials included BoNT serotypes A, B and E spiked into buffer, milk, meat extract and serum. Different methods were applied by the participants combining different principles of detection, identification and quantification. Based on qualitative assays, 95% of all results reported were correct. Successful strategies for BoNT detection were based on a combination of complementary immunological, MS-based and functional methods or on suitable functional in vivo/in vitro approaches (mouse bioassay, hemidiaphragm assay and Endopep-MS assay). Quantification of BoNT/A, BoNT/B and BoNT/E was performed by 48% of participating laboratories. It turned out that precise quantification of BoNT was difficult, resulting in a substantial scatter of quantitative data. This was especially true for results obtained by the mouse bioassay which is currently considered as "gold standard" for BoNT detection. The results clearly demonstrate the urgent need for certified BoNT reference materials and the development of methods replacing animal testing. In this context, the BoNT PT provided the valuable information that both the Endopep-MS assay and the hemidiaphragm assay delivered quantitative results superior to the mouse bioassay.
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Affiliation(s)
- Sylvia Worbs
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestrasse 10, 13353 Berlin, Germany.
| | - Uwe Fiebig
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestrasse 10, 13353 Berlin, Germany.
| | - Reinhard Zeleny
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440 Geel, Belgium.
| | - Heinz Schimmel
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440 Geel, Belgium.
| | - Andreas Rummel
- toxogen GmbH, Feodor-Lynen-Strasse 35, 30625 Hannover, Germany.
| | | | - Brigitte G Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Seestrasse 10, 13353 Berlin, Germany.
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