1
|
Ambrin G, Cai S, Singh BR. Critical analysis in the advancement of cell-based assays for botulinum neurotoxin. Crit Rev Microbiol 2023; 49:1-17. [PMID: 35212259 DOI: 10.1080/1040841x.2022.2035315] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The study on botulinum neurotoxins (BoNTs) has rapidly evolved for their structure and functions as opposed to them being poisons or cures. Since their discoveries, the scientific community has come a long way in understanding BoNTs' structure and biological activity. Given its current application as a tool for understanding neurocellular activity and as a drug against over 800 neurological disorders, relevant and sensitive assays have become critical for biochemical, physiological, and pharmacological studies. The natural entry of the toxin being ingestion, it has also become important to examine its mechanism while crossing the epithelial cell barrier. Several techniques and methodologies have been developed, for its entry, pharmacokinetics, and biological activity for identification, and drug efficacy both in vivo and in vitro conditions. However, each of them presents its own challenges. The cell-based assay is a platform that exceeds the sensitivity of mouse bioassay while encompassing all the steps of intoxication including cell binding, transcytosis, endocytosis, translocation and proteolytic activity. In this article we review in detail both the neuronal and nonneuronal based cellular interaction of BoNT involving its transportation, and interaction with the targeted cells, and intracellular activities.
Collapse
Affiliation(s)
- Ghuncha Ambrin
- Department of Biomedical Engineering and Biotechnology, University of Massachusetts, Dartmouth, MA, USA.,Department of Chemistry and Biochemistry, University of Massachusetts, Dartmouth, MA, USA
| | - Shuowei Cai
- Department of Chemistry and Biochemistry, University of Massachusetts, Dartmouth, MA, USA
| | - Bal Ram Singh
- Institute of Advanced Sciences, Botulinum Research Center, Dartmouth, MA, USA
| |
Collapse
|
2
|
Fabris F, Šoštarić P, Matak I, Binz T, Toffan A, Simonato M, Montecucco C, Pirazzini M, Rossetto O. Detection of VAMP Proteolysis by Tetanus and Botulinum Neurotoxin Type B In Vivo with a Cleavage-Specific Antibody. Int J Mol Sci 2022; 23:ijms23084355. [PMID: 35457172 PMCID: PMC9024618 DOI: 10.3390/ijms23084355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/08/2022] [Accepted: 04/12/2022] [Indexed: 11/17/2022] Open
Abstract
Tetanus and Botulinum type B neurotoxins are bacterial metalloproteases that specifically cleave the vesicle-associated membrane protein VAMP at an identical peptide bond, resulting in inhibition of neuroexocytosis. The minute amounts of these neurotoxins commonly used in experimental animals are not detectable, nor is detection of their VAMP substrate sensitive enough. The immune detection of the cleaved substrate is much more sensitive, as we have previously shown for botulinum neurotoxin type A. Here, we describe the production in rabbit of a polyclonal antibody raised versus a peptide encompassing the 13 residues C-terminal with respect to the neurotoxin cleavage site. The antibody was affinity purified and found to recognize, with high specificity and selectivity, the novel N-terminus of VAMP that becomes exposed after cleavage by tetanus toxin and botulinum toxin type B. This antibody recognizes the neoepitope not only in native and denatured VAMP but also in cultured neurons and in neurons in vivo in neurotoxin-treated mice or rats, suggesting the great potential of this novel tool to elucidate tetanus and botulinum B toxin activity in vivo.
Collapse
Affiliation(s)
- Federico Fabris
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
| | - Petra Šoštarić
- Department of Pharmacology, School of Medicine, University of Zagreb, Šalata 11, 10000 Zagreb, Croatia; (P.Š.); (I.M.)
| | - Ivica Matak
- Department of Pharmacology, School of Medicine, University of Zagreb, Šalata 11, 10000 Zagreb, Croatia; (P.Š.); (I.M.)
| | - Thomas Binz
- Institute of Cellular Biochemistry, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany;
| | - Anna Toffan
- Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell’Università 10, 35020 Legnaro, Italy;
| | - Morena Simonato
- Institute of Neuroscience, Italian Research Council, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy;
| | - Cesare Montecucco
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
- Institute of Neuroscience, Italian Research Council, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy;
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
- Interdepartmental Research Center of Myology CIR-Myo, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
- Correspondence: (M.P.); (O.R.)
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
- Institute of Neuroscience, Italian Research Council, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy;
- Interdepartmental Research Center of Myology CIR-Myo, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
- Correspondence: (M.P.); (O.R.)
| |
Collapse
|
3
|
Zhuang QQ, Chen RT, Zheng YJ, Huang KY, Peng HP, Lin Z, Xia XH, Chen W, Deng HH. Detection of tetanus toxoid with fluorescent tetanus human IgG-AuNC-based immunochromatography test strip. Biosens Bioelectron 2021; 177:112977. [PMID: 33434779 DOI: 10.1016/j.bios.2021.112977] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/31/2020] [Accepted: 01/03/2021] [Indexed: 11/29/2022]
Abstract
Assays for detecting tetanus toxoid are of great significance to be applied in the research of the safety testing of tetanus vaccine. Currently, guinea pigs or mice are usually used to evaluate the toxicity in these assays. Herein, a facile and quick biomineralization process was carried out to generate tetanus human immunoglobulin G (Tet-IgG)-functionalized Au nanoclusters (Tet-IgG-AuNCs). The obtained Tet-IgG-AuNCs exhibited strong red emission with a photoluminescence quantum yield of 13%. Based on surface plasmon resonance measurements, the apparent dissociation constant of the Tet-IgG-AuNC-tetanus toxoid complexes was measured to be 2.27 × 10-8 M. A facile detection approach was developed using a fluorescent Tet-IgG-AuNC-based immunochromatography test strip. By utilizing the high-brightness fluorescent Tet-IgG-AuNCs, this immunosensor showed favorable sensitivity with a detection limit at the level of 0.03 μg/mL. Further results demonstrated that this assay can reliably detect tetanus toxoid and therefore might provide a novel method to replace animal tests for the quantification of tetanus toxicity. Moreover, the antibody-AuNC-based immunochromatography test strip platform serves as a promising candidate to develop new approaches for detecting targeted antigens and biological events of interest.
Collapse
Affiliation(s)
- Quan-Quan Zhuang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China; Department of Pharmacy, Affiliated Quanzhou First Hospital of Fujian Medical University, Quanzhou, 362000, China
| | - Rui-Ting Chen
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China
| | - Yi-Jing Zheng
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China
| | - Kai-Yuan Huang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China
| | - Hua-Ping Peng
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China
| | - Zhen Lin
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China
| | - Xing-Hua Xia
- State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Wei Chen
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China.
| | - Hao-Hua Deng
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou, 350004, China.
| |
Collapse
|
4
|
Transferability study of the BINACLE (binding and cleavage) assay for in vitro determination of botulinum neurotoxin activity. Biologicals 2020; 67:81-87. [PMID: 32739117 DOI: 10.1016/j.biologicals.2020.06.007] [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: 05/13/2020] [Revised: 06/24/2020] [Accepted: 06/28/2020] [Indexed: 11/23/2022] Open
Abstract
The muscle-relaxing effects of the botulinum neurotoxin (BoNT) serotypes A and B are widely used in clinical and aesthetic medicine. The standard method for measuring the biological activity of pharmaceutical BoNT products is a mouse bioassay. In line with the European Directive 2010/63/EU, a replacement by an animal-free method would be desirable. Whereas the existing approved in vitro methods for BoNT activity measurements are product-specific and not freely available for all users, the "binding and cleavage" (BINACLE) assay could become a widely applicable alternative. This method quantifies active BoNT molecules based on their specific receptor-binding and proteolytic properties and can be applied to all BoNT products on the European market. Here we describe the results of a transferability study, in which identical BoNT samples were tested in the BINACLE assay in four laboratories. All participants successfully performed the method and observed clear dose-response relationships. Assay variability was within an acceptable range. These data indicate that the BoNT BINACLE assay is robust and can be straightforwardly transferred between laboratories. They thus provide an appropriate basis for future studies to further substantiate the suitability of the BINACLE assay for the potency determination of BoNT products.
Collapse
|
5
|
Abstract
Tetanus is a neurologic disease of humans and animals characterized by spastic paralysis. Tetanus is caused by tetanus toxin (TeNT) produced by Clostridium tetani, an environmental soilborne, gram-positive, sporulating bacterium. The disease most often results from wound contamination by soil containing C. tetani spores. Horses, sheep, and humans are highly sensitive to TeNT, whereas cattle, dogs, and cats are more resistant. The diagnosis of tetanus is mainly based on the characteristic clinical signs. Identification of C. tetani at the wound site is often difficult.
Collapse
|
6
|
Gray B, Cadd V, Elliott M, Beard M. The in vitro detection of botulinum neurotoxin-cleaved endogenous VAMP is epitope-dependent. Toxicol In Vitro 2018; 48:255-261. [PMID: 29373835 DOI: 10.1016/j.tiv.2018.01.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/17/2018] [Accepted: 01/22/2018] [Indexed: 11/25/2022]
Abstract
The in vitro potency of botulinum neurotoxin (BoNT) serotypes is often measured by monitoring cleavage of their soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein substrates. A frequently used method is Western blot, whereby the full-length protein and cleaved form migrate at different molecular weights. Until now, it has been extremely difficult to detect the cleaved cellular form of the SNARE protein vesicle associated membrane protein 1, 2 or 3 (VAMP1, 2 or 3) by Western blot. These VAMP isoforms are the substrates of BoNT serotypes BoNT/B, D, F and G as well as tetanus neurotoxin. Using custom made anti-VAMP antibodies against epitopes either side of the cleavage sites for BoNT/B, BoNT/D and BoNT/F, we have successfully detected the cleaved C-terminal VAMP fragment in cortical neurons. These new antibodies enable quantitative assessment of the potency of VAMP-cleaving neurotoxins by a gain of signal Western blot assay.
Collapse
Affiliation(s)
- B Gray
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK.
| | - V Cadd
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK
| | - M Elliott
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK
| | - M Beard
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon OX14 4RY, UK
| |
Collapse
|
7
|
Wild E, Bonifas U, Klimek J, Trösemeier JH, Krämer B, Kegel B, Behrensdorf-Nicol HA. In vitro potency determination of botulinum neurotoxin B based on its receptor-binding and proteolytic characteristics. Toxicol In Vitro 2016; 34:97-104. [PMID: 27032463 DOI: 10.1016/j.tiv.2016.03.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 03/21/2016] [Indexed: 01/09/2023]
Abstract
Botulinum neurotoxins (BoNTs) are the most potent toxins known. However, the paralytic effect caused by BoNT serotypes A and B is taken advantage of to treat different forms of dystonia and in cosmetic procedures. Due to the increasing areas of application, the demand for BoNTs A and B is rising steadily. Because of the high toxicity, it is mandatory to precisely determine the potency of every produced BoNT batch, which is usually accomplished by performing toxicity testing (LD50 test) in mice. Here we describe an alternative in vitro assay for the potency determination of the BoNT serotype B. In this assay, the toxin is first bound to its specific receptor molecules. After the proteolytic subunit of the toxin has been released and activated by chemical reduction, it is exposed to synaptobrevin, its substrate protein. Finally the proteolytic cleavage is quantified by an antibody-mediated detection of the neoepitope, reaching a detection limit below 0.1mouseLD50/ml. Thus, the assay, named BoNT/B binding and cleavage assay (BoNT/B BINACLE), takes into account the binding as well as the protease function of the toxin, thereby measuring its biological activity.
Collapse
Affiliation(s)
- Emina Wild
- Veterinary Medicine Division, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicals), Langen, Germany
| | - Ursula Bonifas
- Veterinary Medicine Division, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicals), Langen, Germany
| | - Jolanta Klimek
- Veterinary Medicine Division, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicals), Langen, Germany
| | - Jan-Hendrik Trösemeier
- Microbiology Division, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicals), Langen, Germany; Molecular Bioinformatics, Institute of Computer Science, Johann Wolfgang Goethe University, Frankfurt am Main, Germany
| | - Beate Krämer
- Veterinary Medicine Division, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicals), Langen, Germany
| | - Birgit Kegel
- Veterinary Medicine Division, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicals), Langen, Germany
| | - Heike A Behrensdorf-Nicol
- Veterinary Medicine Division, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicals), Langen, Germany.
| |
Collapse
|
8
|
Behrensdorf-Nicol HA, Bonifas U, Isbrucker R, Ottiger H, Tierney R, Hanschmann KM, Weisser K, Krämer B. Results of an international transferability study of the BINACLE (binding and cleavage) assay for in vitro detection of tetanus toxicity. Biologicals 2014; 42:199-204. [PMID: 24882365 DOI: 10.1016/j.biologicals.2014.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 01/21/2014] [Accepted: 05/01/2014] [Indexed: 11/28/2022] Open
Abstract
Tetanus vaccines contain detoxified tetanus neurotoxin. In order to check for residual toxicity, the detoxified material (toxoid) has to be tested in guinea pigs. These tests are time-consuming and raise animal welfare issues. In line with the "3R" principles of replacing, reducing and refining animal tests, the "binding and cleavage" (BINACLE) assay for detection of active tetanus neurotoxin has been developed as a potential alternative to toxicity testing in animals. This in vitro test system can discriminate well between toxic and detoxified toxin molecules based on their receptor-binding and proteolytic characteristics. Here we describe an international study to assess the transferability of the BINACLE assay. We show that all participating laboratories were able to successfully perform the assay. Generally, assay variability was within an acceptable range. A toxin concentration-dependent increase of assay signals was observed in all tests. Furthermore, participants were able to detect low tetanus neurotoxin concentrations close to the estimated in vivo detection limit. In conclusion, the data from this study indicate that the methodology of the BINACLE assay seems to be robust, reproducible and easily transferable between laboratories. These findings substantiate our notion that the method can be suitable for the routine testing of tetanus toxoids.
Collapse
Affiliation(s)
- Heike A Behrensdorf-Nicol
- Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Paul-Ehrlich-Strasse 51-59, 63225 Langen, Germany.
| | - Ursula Bonifas
- Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Paul-Ehrlich-Strasse 51-59, 63225 Langen, Germany
| | - Richard Isbrucker
- Health Canada, Centre for Vaccine Evaluation, 100 Eglantine Driveway, Ottawa, Ontario K1A 0K9, Canada
| | - Hanspeter Ottiger
- Institute of Virology and Immunology (IVI), Sensemattstrasse 293, 3147 Mittelhaeusern, Switzerland
| | - Robert Tierney
- Division of Bacteriology, National Institute for Biological Standards and Control, MHRA, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK
| | - Kay-Martin Hanschmann
- Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Paul-Ehrlich-Strasse 51-59, 63225 Langen, Germany
| | - Karin Weisser
- Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Paul-Ehrlich-Strasse 51-59, 63225 Langen, Germany
| | - Beate Krämer
- Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Paul-Ehrlich-Strasse 51-59, 63225 Langen, Germany
| |
Collapse
|
9
|
Behrensdorf-Nicol HA, Bonifas U, Hanschmann KM, Krämer B, Weißer K. Binding and cleavage (BINACLE) assay for the functional in vitro detection of tetanus toxin: Applicability as alternative method for the safety testing of tetanus toxoids during vaccine production. Vaccine 2013; 31:6247-53. [DOI: 10.1016/j.vaccine.2013.10.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 09/25/2013] [Accepted: 10/08/2013] [Indexed: 02/01/2023]
|
10
|
Sesardic T. Bioassays for evaluation of medical products derived from bacterial toxins. Curr Opin Microbiol 2012; 15:310-6. [PMID: 22651974 DOI: 10.1016/j.mib.2012.05.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 05/14/2012] [Indexed: 12/14/2022]
Abstract
Bioassays play central role in evaluation of biological products and those derived from bacterial toxins often rely exclusively on in vivo models for assurance of safety and potency. This chapter reviews existing regulatory approved methods designed to provide information on potency and safety of complex biological medicines with an insight into strategies considered for alternative procedures.
Collapse
Affiliation(s)
- Thea Sesardic
- Division of Bacteriology, National Institute for Biological Standards and Control, South Mimms, Potters Bar, Hertfordshire EN6 3QG, United Kingdom.
| |
Collapse
|
11
|
A label-free biosensor assay for botulinum neurotoxin B in food and human serum. Anal Biochem 2011; 410:281-8. [DOI: 10.1016/j.ab.2010.11.045] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 11/25/2010] [Accepted: 11/30/2010] [Indexed: 11/20/2022]
|
12
|
Behrensdorf-Nicol HA, Bonifas U, Kegel B, Silberbach K, Krämer B, Weißer K. In vitro determination of tetanus toxicity by an endopeptidase assay linked to a ganglioside-binding step. Toxicol In Vitro 2010; 24:988-94. [DOI: 10.1016/j.tiv.2009.12.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 12/14/2009] [Accepted: 12/18/2009] [Indexed: 11/26/2022]
|
13
|
Abstract
Sensitive and rapid detection of botulinum neurotoxins (BoNTs), the most poisonous substances known to date, is essential for studies of medical applications of BoNTs and detection of poisoned food, as well as for response to potential bioterrorist threats. Currently, the most common method of BoNT detection is the mouse bioassay. While this assay is sensitive, it is slow, quite expensive, has limited throughput and requires sacrificing animals. Herein, we discuss and compare recently developed alternative in vitro detection methods and assess their ability to supplement or replace the mouse bioassay in the analysis of complex matrix samples.
Collapse
Affiliation(s)
- Petr Čapek
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA;
| | - Tobin J. Dickerson
- Department of Chemistry and Worm Institute for Research and Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
- Author to whom correspondence should be addressed; ; Tel.: +1-858-784-2522; Fax: +1-858-784-2590
| |
Collapse
|
14
|
Čapek P, Dickerson TJ. Sensing the deadliest toxin: technologies for botulinum neurotoxin detection. Toxins (Basel) 2010; 2:24-53. [PMID: 22069545 PMCID: PMC3206617 DOI: 10.3390/toxins2020024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 12/17/2009] [Accepted: 12/22/2009] [Indexed: 11/16/2022] Open
Abstract
Sensitive and rapid detection of botulinum neurotoxins (BoNTs), the most poisonous substances known to date, is essential for studies of medical applications of BoNTs and detection of poisoned food, as well as for response to potential bioterrorist threats. Currently, the most common method of BoNT detection is the mouse bioassay. While this assay is sensitive, it is slow, quite expensive, has limited throughput and requires sacrificing animals. Herein, we discuss and compare recently developed alternative in vitro detection methods and assess their ability to supplement or replace the mouse bioassay in the analysis of complex matrix samples.
Collapse
Affiliation(s)
- Petr Čapek
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA;
| | - Tobin J. Dickerson
- Department of Chemistry and Worm Institute for Research and Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| |
Collapse
|
15
|
New highly specific botulinum type C1 endopeptidase immunoassays utilising SNAP25 or Syntaxin substrates. J Immunol Methods 2009; 343:21-7. [PMID: 19176217 DOI: 10.1016/j.jim.2009.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 01/07/2009] [Accepted: 01/08/2009] [Indexed: 11/22/2022]
Abstract
Botulinum neurotoxins contain proteases that cleave specific intra-neural proteins essential for neurotransmitter release. Toxin types A, C1 and E intra-cellularly cleave SNAP25 and/or Syntaxin (type C1 only) resulting in a flaccid paralysis. Although highly sensitive, robust in vitro endopeptidase immunoassays have been developed for some serotypes, an endopeptidase immunoassay for type C1 has not previously been described. The current studies utilised solid phase synthesized SNAP25(137-206) peptide substrate, and a new specific antibody to the SNAP25(191-198) octapeptide epitope that becomes exposed following cleavage by type C1 toxin. The highly specific nature of the detecting antibody was illustrated by the failure of anti-SNAP25(191-198) to recognise the type A cleavage product which differs by just one amino acid residue. Conversely, anti-SNAP25(190-197), which recognises the type A cleavage product, fails to cross react with the type C1 toxin cleavage product. Utilising Syntaxin(232-266) peptide substrate, and a specific antibody to the cleavage product epitope, Syntaxin(254-261), it was also possible to develop an endopeptidase immunoassay. Assay sensitivities allowed the detection of less than 0.1 LD(50)/ml (25 pg/ml) of type C1 haemagglutinin-complexed toxin. The assay failed to detect toxin serotypes A, B, D, E, F or G and therefore also provides an alternative highly specific in vitro identity test. In the absence of trypsin inhibitors, the assay is also capable of detecting 2 pg/ml of trypsin activity, or trypsin like contaminants. These new immunoassays will therefore provide highly specific tools for monitoring botulinum toxin light chain endopeptidase activity and serotype identity.
Collapse
|
16
|
Behrensdorf-Nicol H, Kegel B, Bonifas U, Silberbach K, Klimek J, Weißer K, Krämer B. Residual enzymatic activity of the tetanus toxin light chain present in tetanus toxoid batches used for vaccine production. Vaccine 2008; 26:3835-41. [DOI: 10.1016/j.vaccine.2008.05.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Revised: 04/30/2008] [Accepted: 05/07/2008] [Indexed: 11/24/2022]
|