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Jiang Y, Wang R, Guo J, Cheng K, Chen L, Wang X, Li Y, Du P, Gao C, Lu J, Yu Y, Yang Z. Isolation and characterization of Hc-targeting chimeric heavy chain antibodies neutralizing botulinum neurotoxin type B. Front Immunol 2024; 15:1380694. [PMID: 38779676 PMCID: PMC11109933 DOI: 10.3389/fimmu.2024.1380694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 04/11/2024] [Indexed: 05/25/2024] Open
Abstract
Background Botulinum neurotoxin (BoNT) produced by Clostridium botulinum is one of the most potent known toxins. Moreover, BoNT is classified as one of the most important biological warfare agents that threatens the biosafety of the world. Currently, the approved treatment for botulism in humans is the use of polyvalent horse serum antitoxins. However, they are greatly limited because of insufficient supply and adverse reactions. Thus, treatment of human botulism requires the development of effective toxin-neutralizing antibodies. Considering their advantages, neutralizing nanobodies will play an increasing role as BoNTs therapeutics. Methods Herein, neutralizing nanobodies binding to the heavy chain (Hc) domain of BoNT/B (BHc) were screened from a phage display library. Then, BoNT/B-specific clones were identified and fused with the human Fc fragment (hFc) to form chimeric heavy chain antibodies. Finally, the affinity, specificity, and neutralizing activity of antibodies against BoNT/B in vivo were evaluated. Results The B5-hFc, B9-hFc and B12-hFc antibodies demonstrated high affinity for BHc in the nanomolar range. The three antibodies were proven to have potent neutralizing activity against BoNT/B in vivo. Conclusion The results demonstrate that inhibiting toxin binding to the host receptor is an efficient strategy and the three antibodies could be used as candidates for the further development of drugs to prevent and treat botulism.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Jiansheng Lu
- Beijing Institute of Biotechnology, Beijing, China
| | - Yunzhou Yu
- Beijing Institute of Biotechnology, Beijing, China
| | - Zhixin Yang
- Beijing Institute of Biotechnology, Beijing, China
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Li Z, Li B, Lu J, Liu X, Tan X, Wang R, Du P, Yu S, Xu Q, Pang X, Yu Y, Yang Z. Biological and Immunological Characterization of a Functional L-HN Derivative of Botulinum Neurotoxin Serotype F. Toxins (Basel) 2023; 15:toxins15030200. [PMID: 36977091 PMCID: PMC10056376 DOI: 10.3390/toxins15030200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) can cause nerve paralysis syndrome in mammals and other vertebrates. BoNTs are the most toxic biotoxins known and are classified as Class A biological warfare agents. BoNTs are mainly divided into seven serotypes A-G and new neurotoxins BoNT/H and BoNT/X, which have similar functions. BoNT proteins are 150 kDa polypeptide consisting of two chains and three domains: the light chain (L, catalytic domain, 50 kDa) and the heavy chain (H, 100 kDa), which can be divided into an N-terminal membrane translocation domain (HN, 50 kDa) and a C-terminal receptor binding domain (Hc, 50 kDa). In current study, we explored the immunoprotective efficacy of each functional molecule of BoNT/F and the biological characteristics of the light chain-heavy N-terminal domain (FL-HN). The two structure forms of FL-HN (i.e., FL-HN-SC: single chain FL-HN and FL-HN-DC: di-chain FL-HN) were developed and identified. FL-HN-SC could cleave the vesicle associated membrane protein 2 (VAMP2) substrate protein in vitro as FL-HN-DC or FL. While only FL-HN-DC had neurotoxicity and could enter neuro-2a cells to cleave VAMP2. Our results showed that the FL-HN-SC had a better immune protection effect than the Hc of BoNT/F (FHc), which indicated that L-HN-SC, as an antigen, provided the strongest protective effects against BoNT/F among all the tested functional molecules. Further in-depth research on the different molecular forms of FL-HN suggested that there were some important antibody epitopes at the L-HN junction of BoNT/F. Thus, FL-HN-SC could be used as a subunit vaccine to replace the FHc subunit vaccine and/or toxoid vaccine, and to develop antibody immune molecules targeting L and HN domains rather than the FHc domain. FL-HN-DC could be used as a new functional molecule to evaluate and explore the structure and activity of toxin molecules. Further exploration of the biological activity and molecular mechanism of the functional FL-HN or BoNT/F is warranted.
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Affiliation(s)
- Zhiying Li
- Beijing Institute of Biotechnology, Beijing 100071, China
- Pharmaceutical College, Henan University, Kaifeng 475001, China
| | - Bolin Li
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Jiansheng Lu
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Xuyang Liu
- Beijing Institute of Biotechnology, Beijing 100071, China
- Pharmaceutical College, Henan University, Kaifeng 475001, China
| | - Xiao Tan
- Beijing Institute of Biotechnology, Beijing 100071, China
- Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing 100044, China
| | - Rong Wang
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Peng Du
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Shuo Yu
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Qing Xu
- Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing 100044, China
| | - Xiaobin Pang
- Pharmaceutical College, Henan University, Kaifeng 475001, China
| | - Yunzhou Yu
- Beijing Institute of Biotechnology, Beijing 100071, China
- Correspondence: (Y.Y.); (Z.Y.)
| | - Zhixin Yang
- Beijing Institute of Biotechnology, Beijing 100071, China
- Correspondence: (Y.Y.); (Z.Y.)
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Panditrao MV, Chung CH, Khouri JM, Barash JR, Motter RN, Dover N, Arnon SS. Dual-Toxin ("Bivalent") Infant Botulism in California, 1976-2020: Epidemiologic, Clinical, and Laboratory Aspects. J Pediatr 2023; 253:8-13. [PMID: 35977619 DOI: 10.1016/j.jpeds.2022.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 07/05/2022] [Accepted: 08/11/2022] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess the consequences of infant botulism that result from Clostridium botulinum strains that produce 2 botulinum toxin serotypes, termed "bivalent." STUDY DESIGN Epidemiologic investigations used a standard questionnaire. Clostridium botulinum strains were isolated by standard methods. Botulinum neurotoxin (BoNT) serotypes and the relative amounts of toxins produced were identified using the standard mouse bioassay. BoNT subtypes and genomic locations were identified by DNA nucleotide sequencing. RESULTS Thirty bivalent cases of infant botulism occurred in the 45 years (1976-2020), representing 2.0% of all California infant botulism cases, in the 3 geographic regions of southern California, the southern Central Valley, and mid-northern California. Toxin serotype combinations were Ba (n = 22), Bf (n = 7), and Ab (n = 1). More patients with illness caused by bivalent C botulinum Ba and Bf strains needed endotracheal intubation at hospital admission, 60.0% (18/30), than did patients with illness caused by monovalent BoNT/B strains, 34.3% (152/443). The Cbotulinum Ba and Bf strains produced BoNT/B5 and either BoNT/A4 or /F2. The Ab strain produced BoNT/A2 and /B1. All toxin gene clusters were on plasmids. CONCLUSIONS Infant botulism caused by bivalent Cbotulinum strains occurs sporadically and in diverse locations in California. Affected patients with bivalent Ba and Bf strains lacked distinguishing epidemiological features but appeared to be more severely paralyzed at hospital presentation than patients with illness caused by only BoNT/B. These bivalent strains produced BoNT subtypes A2, A4, B1, B5, and F2, and all toxin gene clusters were on plasmids.
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Affiliation(s)
- Mayuri V Panditrao
- Epidemiology, Surveillance, and Modeling Branch, COVID-19 Response California Department of Public Health, Richmond, CA
| | - Connie H Chung
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Jessica M Khouri
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Center for Infectious Diseases, California Department of Public Health, Richmond, CA.
| | - Jason R Barash
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Ruth N Motter
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Nir Dover
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Stephen S Arnon
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
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Cai S, Kumar R, Singh BR. Clostridial Neurotoxins: Structure, Function and Implications to Other Bacterial Toxins. Microorganisms 2021; 9:2206. [PMID: 34835332 PMCID: PMC8618262 DOI: 10.3390/microorganisms9112206] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/19/2021] [Accepted: 10/19/2021] [Indexed: 01/20/2023] Open
Abstract
Gram-positive bacteria are ancient organisms. Many bacteria, including Gram-positive bacteria, produce toxins to manipulate the host, leading to various diseases. While the targets of Gram-positive bacterial toxins are diverse, many of those toxins use a similar mechanism to invade host cells and exert their functions. Clostridial neurotoxins produced by Clostridial tetani and Clostridial botulinum provide a classical example to illustrate the structure-function relationship of bacterial toxins. Here, we critically review the recent progress of the structure-function relationship of clostridial neurotoxins, including the diversity of the clostridial neurotoxins, the mode of actions, and the flexible structures required for the activation of toxins. The mechanism clostridial neurotoxins use for triggering their activity is shared with many other Gram-positive bacterial toxins, especially molten globule-type structures. This review also summarizes the implications of the molten globule-type flexible structures to other Gram-positive bacterial toxins. Understanding these highly dynamic flexible structures in solution and their role in the function of bacterial toxins not only fills in the missing link of the high-resolution structures from X-ray crystallography but also provides vital information for better designing antidotes against those toxins.
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Affiliation(s)
- Shuowei Cai
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, Dartmouth, MA 02747, USA
| | - Raj Kumar
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA; (R.K.); (B.R.S.)
| | - Bal Ram Singh
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA; (R.K.); (B.R.S.)
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Closed Genome Sequence of Clostridium botulinum Strain IBCA10-7060 Type Bh. Microbiol Resour Announc 2021; 10:e0038321. [PMID: 34435866 PMCID: PMC8388537 DOI: 10.1128/mra.00383-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Clostridium botulinum strain IBCA10-7060 was isolated from a stool specimen from an infant botulism patient and is the only Clostridium botulinum strain known that produces botulinum toxin type H. We present here its 4.09-Mbp closed genome sequence.
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Descriptive Epidemiology of Infant Botulism in California: The First 40 Years. J Pediatr 2020; 227:247-257.e3. [PMID: 32800814 DOI: 10.1016/j.jpeds.2020.08.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 07/11/2020] [Accepted: 08/06/2020] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To ascertain the descriptive epidemiology of infant botulism, the flaccid paralysis that results when neurotoxigenic Clostridium species produce botulinum toxin (BoNT) in the infant colon, in its first 40 years following initial recognition in California in 1976. STUDY DESIGN Cases were defined by laboratory identification of BoNT and/or neurotoxigenic Clostridium species in patients' feces. Parents were interviewed using a structured questionnaire. Descriptive epidemiologic characteristics were compared between 1976-1996 and 1997-2016. RESULTS From 1976-2016, 1345 cases of infant botulism occurred in 45 of 58 California counties (6.5 cases/100 000 live-births/year) caused by BoNT types A, B, Ba, Bf, and F; 88% of cases were ≤6 months of age and 51% were female. Cases were white (84.2%), Asian (8.9%), other races (3.8%), and African American (2.8%); 29.4% of cases were Hispanic. More than 99% of cases were hospitalized. Case occurrence peaked in summer-fall. Of 8 designated geographic regions, the Central Coast counties had 3 times the statewide incidence in both 20-year time periods. Breast-fed patients (83%) were more than twice as old at onset as formula-fed patients (median, 4.4 vs 1.7 months, respectively; P < .001). BoNT/A cases were older at onset than BoNT/B cases (median, 3.8 vs 2.9 months, respectively; P < .001). CONCLUSIONS Comprehensive continuous surveillance of infant botulism for 40 years in a large, diversely populated state identified fundamental epidemiologic characteristics of this uncommon illness. Unusual features included greater than 99% case hospitalization, absence of male preponderance, and a distinctive age distribution.
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Matsumura T, Amatsu S, Misaki R, Yutani M, Du A, Kohda T, Fujiyama K, Ikuta K, Fujinaga Y. Fully Human Monoclonal Antibodies Effectively Neutralizing Botulinum Neurotoxin Serotype B. Toxins (Basel) 2020; 12:toxins12050302. [PMID: 32392791 PMCID: PMC7291131 DOI: 10.3390/toxins12050302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/03/2020] [Accepted: 05/04/2020] [Indexed: 01/12/2023] Open
Abstract
Botulinum neurotoxin (BoNT) is the most potent natural toxin known. Of the seven BoNT serotypes (A to G), types A, B, E, and F cause human botulism. Treatment of human botulism requires the development of effective toxin-neutralizing antibodies without side effects such as serum sickness and anaphylaxis. In this study, we generated fully human monoclonal antibodies (HuMAbs) against serotype B BoNT (BoNT/B1) using a murine–human chimera fusion partner cell line named SPYMEG. Of these HuMAbs, M2, which specifically binds to the light chain of BoNT/B1, showed neutralization activity in a mouse bioassay (approximately 10 i.p. LD50/100 µg of antibody), and M4, which binds to the C-terminal of heavy chain, showed partial protection. The combination of two HuMAbs, M2 (1.25 µg) and M4 (1.25 µg), was able to completely neutralize BoNT/B1 (80 i.p. LD50) with a potency greater than 80 i.p. LD50/2.5 µg of antibodies, and was effective both prophylactically and therapeutically in the mouse model of botulism. Moreover, this combination showed broad neutralization activity against three type B subtypes, namely BoNT/B1, BoNT/B2, and BoNT/B6. These data demonstrate that the combination of M2 and M4 is promising in terms of a foundation for new human therapeutics for BoNT/B intoxication.
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Affiliation(s)
- Takuhiro Matsumura
- Department of Bacteriology, Graduate School of Medical Sciences, Kanazawa University, Takara-machi, Kanazawa, Ishikawa 920-8640, Japan; (T.M.); (S.A.); (M.Y.)
| | - Sho Amatsu
- Department of Bacteriology, Graduate School of Medical Sciences, Kanazawa University, Takara-machi, Kanazawa, Ishikawa 920-8640, Japan; (T.M.); (S.A.); (M.Y.)
| | - Ryo Misaki
- Applied Microbiology Laboratory, International Center for Biotechnology, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan; (R.M.); (K.F.)
| | - Masahiro Yutani
- Department of Bacteriology, Graduate School of Medical Sciences, Kanazawa University, Takara-machi, Kanazawa, Ishikawa 920-8640, Japan; (T.M.); (S.A.); (M.Y.)
| | - Anariwa Du
- Department of Virology, Center for Infectious Disease Control, Research Institute for Microbial Diseases, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan; (A.D.); (K.I.)
| | - Tomoko Kohda
- Department of Veterinary Sciences, School of Life and Environmental Sciences, Osaka Prefecture University, Rinkuouraikita, Izumisano, Osaka 598-8531, Japan;
| | - Kazuhito Fujiyama
- Applied Microbiology Laboratory, International Center for Biotechnology, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan; (R.M.); (K.F.)
| | - Kazuyoshi Ikuta
- Department of Virology, Center for Infectious Disease Control, Research Institute for Microbial Diseases, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan; (A.D.); (K.I.)
- The Japan Science and Technology Agency/Japan International Cooperation Agency, Science and Technology Research Partnership for Sustainable Development, Tokyo 102-0076, Japan
| | - Yukako Fujinaga
- Department of Bacteriology, Graduate School of Medical Sciences, Kanazawa University, Takara-machi, Kanazawa, Ishikawa 920-8640, Japan; (T.M.); (S.A.); (M.Y.)
- Correspondence: ; Tel.: +81-76-265-2200
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Harris RA, Anniballi F, Austin JW. Adult Intestinal Toxemia Botulism. Toxins (Basel) 2020; 12:E81. [PMID: 31991691 PMCID: PMC7076759 DOI: 10.3390/toxins12020081] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 01/20/2020] [Accepted: 01/22/2020] [Indexed: 12/30/2022] Open
Abstract
Intoxication with botulinum neurotoxin can occur through various routes. Foodborne botulism results after consumption of food in which botulinum neurotoxin-producing clostridia (i.e., Clostridium botulinum or strains of Clostridiumbutyricum type E or Clostridiumbaratii type F) have replicated and produced botulinum neurotoxin. Infection of a wound with C. botulinum and in situ production of botulinum neurotoxin leads to wound botulism. Colonization of the intestine by neurotoxigenic clostridia, with consequent production of botulinum toxin in the intestine, leads to intestinal toxemia botulism. When this occurs in an infant, it is referred to as infant botulism, whereas in adults or children over 1 year of age, it is intestinal colonization botulism. Predisposing factors for intestinal colonization in children or adults include previous bowel or gastric surgery, anatomical bowel abnormalities, Crohn's disease, inflammatory bowel disease, antimicrobial therapy, or foodborne botulism. Intestinal colonization botulism is confirmed by detection of botulinum toxin in serum and/or stool, or isolation of neurotoxigenic clostridia from the stool, without finding a toxic food. Shedding of neurotoxigenic clostridia in the stool may occur for a period of several weeks. Adult intestinal botulism occurs as isolated cases, and may go undiagnosed, contributing to the low reported incidence of this rare disease.
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Affiliation(s)
- Richard A. Harris
- Botulism Reference Service for Canada, Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Products and Food Branch, Ottawa, ON K1A 0K9, Canada;
| | - Fabrizio Anniballi
- National Reference Centre for Botulism, Microbiological Foodborne Hazard Unit, Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, viale Regina Elena, 29900161 Rome, Italy;
| | - John W. Austin
- Botulism Reference Service for Canada, Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Products and Food Branch, Ottawa, ON K1A 0K9, Canada;
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Manufacturing and Clinical Formulations of Botulinum Neurotoxins. Handb Exp Pharmacol 2020. [PMID: 31932989 DOI: 10.1007/164_2019_311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Botulinum Neurotoxins have always existed in nature, but its paralytic effect on humans due to the consumption of poorly preserved food was not recognized until 18th century. There are 8 serotypes of botulinum neurotoxins (A, B, C, D, E, F, G, H). Serotype A have been the most recognized one and was initially developed for large scale production in 1940's. The first batch for clinical use was produced by Edward Schantz, who collaborated with Dr. Alan Scott, an ophthalmologist, evaluating botulinum neurotoxin to treat strabismus. The process Schantz used had variability and led to inconsistent batch production. However, this process is still used by various manufacturers of commercial botulinum neurotoxin products as the foundation. These manufacturers have refined the manufacturing of botulinum neurotoxins by implementing new advanced techniques, including better potency assays. Despite the improvements in the manufacturing process, botulinum neurotoxins are still one of the most potent molecules and therefore, require special handing and additional safety/security measurements during production.
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The Novel Clostridial Neurotoxin Produced by Strain IBCA10-7060 Is Immunologically Equivalent to BoNT/HA. Toxins (Basel) 2019; 12:toxins12010009. [PMID: 31877649 PMCID: PMC7020490 DOI: 10.3390/toxins12010009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/07/2019] [Accepted: 12/12/2019] [Indexed: 11/16/2022] Open
Abstract
Background: Botulinum neurotoxins (BoNTs) comprise seven agreed-on serotypes, A through G. In 2014, a novel chimeric neurotoxin produced by clostridial strain IBCA10-7060 was reported as BoNT/H, with subsequent names of BoNT/FA or BoNT/HA based on sequence homology of the N-terminus to BoNT/F, the C-terminus to BoNT/A and neutralization studies. The purpose of this study was to define the immunologic identity of the novel BoNT. Methods: monoclonal antibodies (mAbs) to the novel BoNT/H N-terminus were generated by antibody repertoire cloning and yeast display after immunization with BoNT/H LC-HN or BoNT/F LC-HN. Results: 21 unique BoNT/H LC-HN mAbs were obtained; 15 from the BoNT/H LC-HN immunized library (KD 0.78 nM to 182 nM) and six from the BoNT/F-immunized libraries (KD 20.5 nM to 1490 nM). A total of 15 of 21 mAbs also bound catalytically inactive BoNT/H holotoxin. The mAbs bound nine non-overlapping epitopes on the BoNT/H LC-HN. None of the mAbs showed binding to BoNT serotypes A-G, nor any of the seven subtypes of BoNT/F, except for one mAb that weakly bound BoNT/F5. Conclusions: The results, combined with the chimeric structure and neutralization by anti-A, but not anti-F antitoxin indicate that immunologically the novel BoNT is BoNT/HA. This determination has significant implications for existing countermeasures and potential vulnerabilities.
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11
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Tables of Toxicity of Botulinum and Tetanus Neurotoxins. Toxins (Basel) 2019; 11:toxins11120686. [PMID: 31771110 PMCID: PMC6950492 DOI: 10.3390/toxins11120686] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 11/17/2022] Open
Abstract
Tetanus and botulinum neurotoxins are the most poisonous substances known, so much so as to be considered for a possible terrorist use. At the same time, botulinum neurotoxin type A1 is successfully used to treat a variety of human syndromes characterized by hyperactive cholinergic nerve terminals. The extreme toxicity of these neurotoxins is due to their neurospecificity and to their metalloprotease activity, which results in the deadly paralysis of tetanus and botulism. Recently, many novel botulinum neurotoxins and some botulinum-like toxins have been discovered. This large number of toxins differs in terms of toxicity and biological activity, providing a potential goldmine for novel therapeutics and for new molecular tools to dissect vesicular trafficking, fusion, and exocytosis. The scattered data on toxicity present in the literature require a systematic organization to be usable by scientists and clinicians. We have assembled here the data available in the literature on the toxicity of these toxins in different animal species. The internal comparison of these data provides insights on the biological activity of these toxins.
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12
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Safety and Pharmacokinetics of a Four Monoclonal Antibody Combination Against Botulinum C and D Neurotoxins. Antimicrob Agents Chemother 2019:AAC.01270-19. [PMID: 31591130 PMCID: PMC6879217 DOI: 10.1128/aac.01270-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Botulism is caused by botulinum neurotoxin (BoNT), the most poisonous substance known. BoNTs are also classified as Tier 1 biothreat agents due to their high potency and lethality. The existence of seven BoNT serotypes (A-G), which differ between 35% to 68% in amino acid sequence, necessitates the development of serotype specific countermeasures. We present results of a Phase 1 clinical study of an anti-toxin to BoNT serotypes C and D, NTM-1634, which consists of an equimolar mixture of four fully human IgG1 monoclonal antibodies (mAbs), each binding to non-overlapping epitopes on BoNT serotypes C and D resulting in potent toxin neutralization in rodents. This first-in-human study evaluated the safety and pharmacokinetics of escalating doses of NTM-1634 administered intravenously to healthy adults (NCT03046550). Three cohorts of eight healthy subjects received a single intravenous dose of NTM-1634 or placebo at 0.33 mg/kg, 0.66 mg/kg or 1 mg/kg. Follow-up examinations and pharmacokinetic evaluations were continued up to 121 days post-infusion. Subjects were monitored using physical examinations, hematology and chemistry blood tests, and electrocardiograms. Pharmacokinetic parameters were estimated using noncompartmental methods. The results demonstrated that the materials were safe and well-tolerated with the expected half-lives for human mAbs and with minimal anti-drug antibodies detected over the dose ranges and duration of the study.
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13
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Rasetti-Escargueil C, Popoff MR. Antibodies and Vaccines against Botulinum Toxins: Available Measures and Novel Approaches. Toxins (Basel) 2019; 11:toxins11090528. [PMID: 31547338 PMCID: PMC6783819 DOI: 10.3390/toxins11090528] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 08/29/2019] [Accepted: 09/05/2019] [Indexed: 12/18/2022] Open
Abstract
Botulinum neurotoxin (BoNT) is produced by the anaerobic, Gram-positive bacterium Clostridium botulinum. As one of the most poisonous toxins known and a potential bioterrosism agent, BoNT is characterized by a complex mode of action comprising: internalization, translocation and proteolytic cleavage of a substrate, which inhibits synaptic exocytotic transmitter release at neuro-muscular nerve endings leading to peripheral neuroparalysis of the skeletal and autonomic nervous systems. There are seven major serologically distinct toxinotypes (A-G) of BoNT which act on different substrates. Human botulism is generally caused by BoNT/A, B and E. Due to its extreme lethality and potential use as biological weapon, botulism remains a global public health concern. Vaccination against BoNT, although an effective strategy, remains undesirable due to the growing expectation around therapeutic use of BoNTs in various pathological conditions. This review focuses on the current approaches for botulism control by immunotherapy, highlighting the future challenges while the molecular underpinnings among subtypes variants and BoNT sequences found in non-clostridial species remain to be elucidated.
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Affiliation(s)
- Christine Rasetti-Escargueil
- Institut Pasteur, Département de Microbiologie, Unité des Toxines Bactériennes, 25 Rue du Docteur Roux, 75015 Paris, France.
| | - Michel R Popoff
- Institut Pasteur, Département de Microbiologie, Unité des Toxines Bactériennes, 25 Rue du Docteur Roux, 75015 Paris, France.
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14
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Pharmacokinetics of Human Recombinant Anti-Botulinum Toxin Antibodies in Rats. Toxins (Basel) 2019; 11:toxins11060345. [PMID: 31212950 PMCID: PMC6628388 DOI: 10.3390/toxins11060345] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/02/2019] [Accepted: 06/03/2019] [Indexed: 12/18/2022] Open
Abstract
Botulinum neurotoxins (BoNT) are potential biothreat agents due to their high lethality, potency, and ease of distribution, thus the development of antitoxins is a high priority to the US government. This study examined pre-clinical pharmacokinetic studies in rats of four oligoclonal anti-BoNT mAb-based therapeutics (NTM-1631, NTM-1632, NTM-1633, NTM-1634) for five BoNT serotypes (A, B, E, C, and D). NTM-1631, NTM-1632, and NTM-1633 each consist of three IgG1 mAbs, each with a distinct human or humanized variable region which bind to distinct epitopes on BoNT serotype A, B, or E respectively. NTM-1634 consists of four human immunoglobulin G1 (IgG1) mAbs binding BoNT C/D mosaic toxins. The mechanism of these antitoxins requires that three antibodies simultaneously bind toxin to achieve rapid clearance. Rats (total 378) displayed no adverse clinical signs attributed to antibody treatment from any of the antitoxins. Pharmacokinetic evaluation demonstrated that the individual mAbs are slowly eliminated, exhibiting dose-dependent exposure and long elimination half-lives ranging from 6.5 days to 10 days. There were no consistent differences observed between males and females or among the individual antibodies in each formulation in half-life. Anti-drug antibodies (ADA) were observed, as expected for human antibodies administered to rats. The results presented were used to support the clinical investigation of antibody-based botulism antitoxins.
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15
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Schlake T, Thran M, Fiedler K, Heidenreich R, Petsch B, Fotin-Mleczek M. mRNA: A Novel Avenue to Antibody Therapy? Mol Ther 2019; 27:773-784. [PMID: 30885573 DOI: 10.1016/j.ymthe.2019.03.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 03/01/2019] [Accepted: 03/01/2019] [Indexed: 12/12/2022] Open
Abstract
First attempts to use exogenous mRNA for protein expression in vivo were made more than 25 years ago. However, widespread appreciation of in vitro transcribed mRNA as a powerful technology for supplying therapeutic proteins to the body has evolved only during the past few years. Various approaches to turning mRNA into a potent therapeutic have been developed. All of them share utilization of specifically designed, rather than endogenous, sequences and thorough purification protocols. Apart from this, there are two fundamental philosophies, one promoting the use of chemically modified nucleotides, the other advocating restriction to unmodified building blocks. Meanwhile, both strategies have received broad support by successful mRNA-based protein treatments in animal models. For such in vivo use, specifically optimized mRNA had to be combined with potent formulations to enable efficient in vivo delivery. The present review analyzes the applicability of mRNA technology to antibody therapy in all main fields: antitoxins, infectious diseases, and oncology.
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Natural Compounds and Their Analogues as Potent Antidotes against the Most Poisonous Bacterial Toxin. Appl Environ Microbiol 2018; 84:AEM.01280-18. [PMID: 30389764 DOI: 10.1128/aem.01280-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 09/28/2018] [Indexed: 01/30/2023] Open
Abstract
Botulinum neurotoxins (BoNTs), the most poisonous proteins known to humankind, are a family of seven (serotype A to G) immunologically distinct proteins synthesized primarily by different strains of the anaerobic bacterium Clostridium botulinum Being the causative agents of botulism, the toxins block neurotransmitter release by specifically cleaving one of the three soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins, thereby inducing flaccid paralysis. The development of countermeasures and therapeutics against BoNTs is a high-priority research area for public health because of their extreme toxicity and potential for use as biowarfare agents. Extensive research has focused on designing antagonists that block the catalytic activity of BoNTs. In this study, we screened 300 small natural compounds and their analogues extracted from Indian plants for their activity against BoNT serotype A (BoNT/A) as well as its light chain (LCA) using biochemical and cellular assays. One natural compound, a nitrophenyl psoralen (NPP), was identified to be a specific inhibitor of LCA with an in vitro 50% inhibitory concentration (IC50) value of 4.74 ± 0.03 µM. NPP was able to rescue endogenous synaptosome-associated protein 25 (SNAP-25) from cleavage by BoNT/A in human neuroblastoma cells with an IC50 of 12.2 ± 1.7 µM, as well as to prolong the time to the blocking of neutrally elicited twitch tensions in isolated mouse phrenic nerve-hemidiaphragm preparations.IMPORTANCE The long-lasting endopeptidase activity of BoNT is a critical biological activity inside the nerve cell, as it prompts proteolysis of the SNARE proteins, involved in the exocytosis of the neurotransmitter acetylcholine. Thus, the BoNT endopeptidase activity is an appropriate clinical target for designing new small-molecule antidotes against BoNT with the potential to reverse the paralysis syndrome of botulism. In principle, small-molecule inhibitors (SMIs) can gain entry into BoNT-intoxicated cells if they have a suitable octanol-water partition coefficient (log P) value and other favorable characteristics (P. Leeson, Nature 481:455-456, 2012, https://doi.org/10.1038/481455a). Several efforts have been made in the past to develop SMIs, but inhibitors effective under in vitro conditions have not in general been effective in vivo or in cellular models (L. M. Eubanks, M. S. Hixon, W. Jin, S. Hong, et al., Proc Natl Acad Sci U S A 104:2602-2607, 2007, https://doi.org/10.1073/pnas.0611213104). The difference between the in vitro and cellular efficacy presumably results from difficulties experienced by the compounds in crossing the cell membrane, in conjunction with poor bioavailability and high cytotoxicity. The screened nitrophenyl psoralen (NPP) effectively antagonized BoNT/A in both in vitro and ex vivo assays. Importantly, NPP inhibited the BoNT/A light chain but not other general zinc endopeptidases, such as thermolysin, suggesting high selectivity for its target. Small-molecule (nonpeptidic) inhibitors have better oral bioavailability, better stability, and better tissue and cell permeation than antitoxins or peptide inhibitors.
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17
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Lam KH, Sikorra S, Weisemann J, Maatsch H, Perry K, Rummel A, Binz T, Jin R. Structural and biochemical characterization of the protease domain of the mosaic botulinum neurotoxin type HA. Pathog Dis 2018; 76:4982781. [PMID: 29688327 DOI: 10.1093/femspd/fty044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 04/20/2018] [Indexed: 11/13/2022] Open
Abstract
The extreme toxicity of botulinum neurotoxins (BoNTs) relies on their specific cleavage of SNARE proteins, which eventually leads to muscle paralysis. One newly identified mosaic toxin, BoNT/HA (aka H or FA), cleaves VAMP-2 at a unique position between residues L54 and E55, but the molecular basis underlying VAMP-2 recognition of BoNT/HA remains poorly characterized. Here, we report a ∼2.09 Å resolution crystal structure of the light chain protease domain of BoNT/HA (LC/HA). Structural comparison between LC/HA and LC of BoNT/F1 (LC/F1) reveals distinctive hydrophobic and electrostatic features near the active sites, which may explain their different VAMP-2 cleavage sites. When compared to BoNT/F5 that cleaves VAMP-2 at the same site as BoNT/HA, LC/HA displays higher affinity for VAMP-2, which could be caused by their different surface charge properties surrounding a VAMP-2 exosite-binding cleft. Furthermore, systematic mutagenesis studies on VAMP-2 and structural modeling demonstrate that residues R47 to K59 spanning the cleavage site in VAMP-2 may adopt a novel extended conformation when interacting with LC/HA and LC/F5. Taken together, our structure provides new insights into substrate recognition of BoNT/HA and paves the way for rational design of small molecule or peptide inhibitors against LC/HA.
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Affiliation(s)
- Kwok-Ho Lam
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697 USA
| | - Stefan Sikorra
- Institut für Zellbiochemie, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Jasmin Weisemann
- Institut für Toxikologie, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Hannah Maatsch
- Institut für Zellbiochemie, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Kay Perry
- NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Thomas Binz
- Institut für Zellbiochemie, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Rongsheng Jin
- Department of Physiology and Biophysics, University of California, Irvine, CA 92697 USA
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18
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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: 28] [Impact Index Per Article: 4.7] [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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19
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Tehran DA, Pirazzini M. Novel Botulinum Neurotoxins: Exploring Underneath the Iceberg Tip. Toxins (Basel) 2018; 10:toxins10050190. [PMID: 29748471 PMCID: PMC5983246 DOI: 10.3390/toxins10050190] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 05/05/2018] [Accepted: 05/08/2018] [Indexed: 12/26/2022] Open
Abstract
Botulinum neurotoxins (BoNTs), the etiological agents of botulism, are the deadliest toxins known to humans. Yet, thanks to their biological and toxicological features, BoNTs have become sophisticated tools to study neuronal physiology and valuable therapeutics for an increasing number of human disorders. BoNTs are produced by multiple bacteria of the genus Clostridium and, on the basis of their different immunological properties, were classified as seven distinct types of toxin. BoNT classification remained stagnant for the last 50 years until, via bioinformatics and high-throughput sequencing techniques, dozens of BoNT variants, novel serotypes as well as BoNT-like toxins within non-clostridial species have been discovered. Here, we discuss how the now “booming field” of botulinum neurotoxin may shed light on their evolutionary origin and open exciting avenues for future therapeutic applications.
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Affiliation(s)
- Domenico Azarnia Tehran
- Department of Biomedical Sciences, 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.
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20
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A Single Tri-Epitopic Antibody Virtually Recapitulates the Potency of a Combination of Three Monoclonal Antibodies in Neutralization of Botulinum Neurotoxin Serotype A. Toxins (Basel) 2018; 10:toxins10020084. [PMID: 29462889 PMCID: PMC5848185 DOI: 10.3390/toxins10020084] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/05/2018] [Accepted: 02/13/2018] [Indexed: 11/17/2022] Open
Abstract
The standard of treatment for botulism, equine antitoxin, is a foreign protein with associated safety issues and a short serum half-life which excludes its use as a prophylactic antitoxin and makes it a less-than-optimal therapeutic. Due to these limitations, a recombinant monoclonal antibody (mAb) product is preferable. It has been shown that combining three mAbs that bind non-overlapping epitopes leads to highly potent botulinum neurotoxin (BoNT) neutralization. Recently, a triple human antibody combination for BoNT/A has demonstrated potent toxin neutralization in mouse models with no serious adverse events when tested in a Phase I clinical trial. However, a triple antibody therapeutic poses unique development and manufacturing challenges. Thus, potentially to streamline development of BoNT antitoxins, we sought to achieve the potency of multiple mAb combinations in a single IgG-based molecule that has a long serum half-life. The design, production, and testing of a single tri-epitopic IgG1-based mAb (TeAb) containing the binding sites of each of the three parental BoNT/A mAbs yielded an antibody of nearly equal potency to the combination. The approach taken here could be applied to the design and creation of other multivalent antibodies that could be used for a variety of applications, including toxin elimination.
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Khouri JM, Payne JR, Arnon SS. More Clinical Mimics of Infant Botulism. J Pediatr 2018; 193:178-182. [PMID: 29229451 DOI: 10.1016/j.jpeds.2017.09.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/23/2017] [Accepted: 09/19/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To ascertain the actual diagnoses of 76 patients (2005-2015) whose clinical presentations so closely resembled infant botulism that the patients were treated with Human Botulism Immune Globulin Intravenous (BIG-IV; BabyBIG), but whose illnesses subsequently were not laboratory confirmed as infant botulism ("clinical mimics" of infant botulism). STUDY DESIGN The California Department of Public Health produces BIG-IV and distributes it nationwide as a public service (ie, not-for-profit) orphan drug to treat patients hospitalized with suspected infant botulism. During the study period, admission records and discharge summaries for all patients treated with BIG-IV but who lacked a laboratory-confirmed diagnosis of infant botulism were collected and abstracted. The patients' discharge diagnoses were identified, categorized, and compared with previously reported clinical mimics categories for 32 patients (1992-2005). RESULTS From 2005 to 2015, 76 clinical mimic illnesses were identified. These illnesses were distributed into the 5 categories previously reported of (1) probable infant botulism lacking confirmatory testing (26.3%); (2) spinal muscular atrophy (19.7%); (3) miscellaneous (15.8%); (4) metabolic disorders (11.8%); and (5) other infectious diseases (10.6%). Of the 76 clinical mimic illnesses, 15.8% had no alternate diagnosis established and were therefore categorized as undetermined. CONCLUSIONS Over the 23 years 1992-2015, patients presenting with illnesses so clinically similar to infant botulism that they were treated with BIG-IV had actual diagnoses that were distributed into 5 main categories. These categories and their individual components constitute a working bedside differential diagnosis of infant botulism.
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Affiliation(s)
- Jessica M Khouri
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Jessica R Payne
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Stephen S Arnon
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health, Richmond, CA.
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22
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Payne JR, Khouri JM, Jewell NP, Arnon SS. Efficacy of Human Botulism Immune Globulin for the Treatment of Infant Botulism: The First 12 Years Post Licensure. J Pediatr 2018; 193:172-177. [PMID: 29229452 DOI: 10.1016/j.jpeds.2017.10.035] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 10/12/2017] [Accepted: 10/13/2017] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To report the efficacy of Human Botulism Immune Globulin Intravenous (BIG-IV) in the first 12 years following its licensure in 2003 and to characterize its use nationwide in treating patients with infant botulism. STUDY DESIGN Medical records and billing information were collected for US patients treated with BIG-IV from 2003 to 2015. Length of hospital stay (LOS) and hospital charge information for treated patients were compared with the BIG-IV Pivotal Clinical Trial Placebo Group to quantify decreases in LOS and hospital charges. RESULTS The use of BIG-IV reduced mean LOS from 5.7 to 2.2 weeks. This shortened hospital stay resulted in a mean decrease in hospital charges of $88 900 per patient. For all US patients 2003-2015, total decreases in LOS and hospital charges were 66.9 years and $86.2 million, respectively. The decrease in mean LOS was time dependent: BIG-IV treatment on hospital days 0-3 reduced mean LOS by 3.7 weeks (P <.001 vs the BIG-IV Pivotal Clinical Trial Placebo Group), on hospital days 4-7 by 2.6 weeks (P <.001 vs the BIG-IV Pivotal Clinical Trial Placebo Group) and on hospital days 8-10 by just 1 week (P = NS). Since licensure, 1192 patients in 48 states and Washington, DC, have been treated with BIG-IV. CONCLUSIONS The use of BIG-IV since its licensure in 2003 treated approximately 93% of US patients with laboratory-confirmed infant botulism, and prevented >65 years in hospital stay and >$85 million in hospital charges from occurring. The greatest LOS reduction was achieved when BIG-IV was administered soon after hospital admission. Effective and appropriate use of BIG-IV in the US has continued in the postlicensure period.
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Affiliation(s)
- Jessica R Payne
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Jessica M Khouri
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health, Richmond, CA
| | - Nicholas P Jewell
- Division of Biostatistics, School of Public Health, University of California, Berkeley, CA
| | - Stephen S Arnon
- Infant Botulism Treatment and Prevention Program, Infectious Diseases Laboratory Branch, Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health, Richmond, CA.
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23
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Pellett S, Tepp WH, Lin G, Johnson EA. Substrate cleavage and duration of action of botulinum neurotoxin type FA ("H, HA"). Toxicon 2017; 147:38-46. [PMID: 29273248 PMCID: PMC5911199 DOI: 10.1016/j.toxicon.2017.12.048] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 12/15/2017] [Accepted: 12/18/2017] [Indexed: 12/12/2022]
Abstract
Botulinum neurotoxin (BoNT) type FA is the only known naturally occurring chimeric BoNT of domains of BoNT/A and BoNT/F. BoNT/FA consists of an F5-like light chain (LC), a unique heavy chain (HC) translocation domain, and a HC receptor binding domain similar to BoNT/A1. Previous analyses of purified BoNT/FA have indicated a 5-10-fold greater potency in cultured human or rat neurons as compared to BoNT/A1 and a 400-500-fold greater potency compared to BoNT/B1. However, in vivo potency in mice was about 5-fold lower than BoNT/A1 or/B1. In this report, species specificity was examined by cell-based assays using primary neurons from mice and examining VAMP1 and 2 cleavage. The data indicated similar potency of BoNT/FA in primary mouse spinal cord neurons as previously observed in primary rat and human induced pluripotent stem cell (hiPSC) derived neuronal cell models, and equal enzymatic cleavage of mouse VAMP1 and 2 isoforms. Since the duration of action of BoNTs is due to continuous enzymatic activity of the LC in the neuronal cytosol, BoNT/FA was expected to have a short duration of action due to its F-type LC. In this report the duration of action of BoNT/FA was compared to that of BoNT/F1,/F5, and/B1 in both hiPSC derived neurons and in the in vivo mouse model. The data indicate a duration of action of BoNT/FA similar to BoNT/B1, while BoNT/F5 had a short duration of action similar to BoNT/F1.
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Affiliation(s)
- Sabine Pellett
- Department of Bacteriology, University of Wisconsin, 1550 Linden Dr., Madison, WI 53706, USA.
| | - William H Tepp
- Department of Bacteriology, University of Wisconsin, 1550 Linden Dr., Madison, WI 53706, USA.
| | - Guangyun Lin
- Department of Bacteriology, University of Wisconsin, 1550 Linden Dr., Madison, WI 53706, USA.
| | - Eric A Johnson
- Department of Bacteriology, University of Wisconsin, 1550 Linden Dr., Madison, WI 53706, USA.
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A Monoclonal-Monoclonal Antibody Based Capture ELISA for Abrin. Toxins (Basel) 2017; 9:toxins9100328. [PMID: 29057799 PMCID: PMC5666375 DOI: 10.3390/toxins9100328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/09/2017] [Accepted: 10/13/2017] [Indexed: 01/08/2023] Open
Abstract
Abrin, one of the most highly potent toxins in the world, is derived from the plant, Abrus precatorius. Because of its high toxicity, it poses potential bioterror risks. Therefore, a need exists for new reagents and technologies that would be able to rapidly detect abrin contamination as well as lead to new therapeutics. We report here a group of abrin-specific monoclonal antibodies (mAbs) that recognize abrin A-chain, intact A–B chain toxin, and agglutinin by Western blot. Additionally, these mAbs were evaluated for their ability to serve as capture antibodies for a sandwich (capture) ELISA. All possible capture–detector pairs were evaluated and the best antibody pair identified and optimized for a capture ELISA. The capture ELISA based on this capture–detector mAb pair had a limit of detection (L.O.D) of ≈1 ng/mL measured using three independent experiments. The assay did not reveal any false positives with extracts containing other potential ribosome-inactivating proteins (RIPs). Thus, this new capture ELISA uses mAbs for both capture and detection; has no cross-reactivity against other plant RIPs; and has a sensitivity comparable to other reported capture ELISAs using polyclonal antibodies as either capture or detector.
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25
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Yao G, Lam KH, Weisemann J, Peng L, Krez N, Perry K, Shoemaker CB, Dong M, Rummel A, Jin R. A camelid single-domain antibody neutralizes botulinum neurotoxin A by blocking host receptor binding. Sci Rep 2017; 7:7438. [PMID: 28785006 PMCID: PMC5547058 DOI: 10.1038/s41598-017-07457-5] [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: 04/27/2017] [Accepted: 06/23/2017] [Indexed: 01/07/2023] Open
Abstract
Antibody treatment is currently the only available countermeasure for botulism, a fatal illness caused by flaccid paralysis of muscles due to botulinum neurotoxin (BoNT) intoxication. Among the seven major serotypes of BoNT/A-G, BoNT/A poses the most serious threat to humans because of its high potency and long duration of action. Prior to entering neurons and blocking neurotransmitter release, BoNT/A recognizes motoneurons via a dual-receptor binding process in which it engages both the neuron surface polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Previously, we identified a potent neutralizing antitoxin against BoNT/A1 termed ciA-C2, derived from a camelid heavy-chain-only antibody (VHH). In this study, we demonstrate that ciA-C2 prevents BoNT/A1 intoxication by inhibiting its binding to neuronal receptor SV2. Furthermore, we determined the crystal structure of ciA-C2 in complex with the receptor-binding domain of BoNT/A1 (HCA1) at 1.68 Å resolution. The structure revealed that ciA-C2 partially occupies the SV2-binding site on HCA1, causing direct interference of HCA1 interaction with both the N-glycan and peptide-moiety of SV2. Interestingly, this neutralization mechanism is similar to that of a monoclonal antibody in clinical trials, despite that ciA-C2 is more than 10-times smaller. Taken together, these results enlighten our understanding of BoNT/A1 interactions with its neuronal receptor, and further demonstrate that inhibiting toxin binding to the host receptor is an efficient countermeasure strategy.
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Affiliation(s)
- Guorui Yao
- Department of Physiology and Biophysics, University of California, Irvine, California, USA
| | - Kwok-Ho Lam
- Department of Physiology and Biophysics, University of California, Irvine, California, USA
| | - Jasmin Weisemann
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Lisheng Peng
- Department of Urology, Boston Children's Hospital, Department of Microbiology and Immunobiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Nadja Krez
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Kay Perry
- NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Argonne National Laboratory, Argonne, Illinois, USA
| | - Charles B Shoemaker
- Department of Infectious Diseases and Global Health, Tufts Clinical and Translational Science Institute, North Grafton, Massachusetts, USA
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Department of Microbiology and Immunobiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Rongsheng Jin
- Department of Physiology and Biophysics, University of California, Irvine, California, USA.
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Pirazzini M, Rossetto O, Eleopra R, Montecucco C. Botulinum Neurotoxins: Biology, Pharmacology, and Toxicology. Pharmacol Rev 2017; 69:200-235. [PMID: 28356439 PMCID: PMC5394922 DOI: 10.1124/pr.116.012658] [Citation(s) in RCA: 404] [Impact Index Per Article: 57.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The study of botulinum neurotoxins (BoNT) is rapidly progressing in many aspects.
Novel BoNTs are being discovered owing to next generation sequencing, but their
biologic and pharmacological properties remain largely unknown. The molecular
structure of the large protein complexes that the toxin forms with accessory
proteins, which are included in some BoNT type A1 and B1 pharmacological
preparations, have been determined. By far the largest effort has been dedicated to
the testing and validation of BoNTs as therapeutic agents in an ever increasing
number of applications, including pain therapy. BoNT type A1 has been also exploited
in a variety of cosmetic treatments, alone or in combination with other agents, and
this specific market has reached the size of the one dedicated to the treatment of
medical syndromes. The pharmacological properties and mode of action of BoNTs have
shed light on general principles of neuronal transport and protein-protein
interactions and are stimulating basic science studies. Moreover, the wide array of
BoNTs discovered and to be discovered and the production of recombinant BoNTs endowed
with specific properties suggest novel uses in therapeutics with increasing
disease/symptom specifity. These recent developments are reviewed here to provide an
updated picture of the biologic mechanism of action of BoNTs, of their increasing use
in pharmacology and in cosmetics, and of their toxicology.
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Affiliation(s)
- Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
| | - Roberto Eleopra
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
| | - Cesare Montecucco
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
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A three monoclonal antibody combination potently neutralizes multiple botulinum neurotoxin serotype F subtypes. PLoS One 2017; 12:e0174187. [PMID: 28323873 PMCID: PMC5360321 DOI: 10.1371/journal.pone.0174187] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 03/04/2017] [Indexed: 11/19/2022] Open
Abstract
Human botulism is primarily caused by botulinum neurotoxin (BoNT) serotypes A, B and E, with around 1% caused by serotype F (BoNT/F). BoNT/F comprises at least seven different subtypes with the amino acid sequence difference between subtypes as high as 36%. The sequence differences present a significant challenge for generating monoclonal antibodies (mAbs) that can bind, detect and neutralize all BoNT/F subtypes. We used repertoire cloning of immune mouse antibody variable (V) regions and yeast display to generate a panel of 33 lead single chain Fv (scFv) mAbs that bound one or more BoNT/F subtypes with a median equilibrium dissociation constant (KD) of 4.06 × 10-9 M. By diversifying the V-regions of the lead mAbs and selecting for cross reactivity we generated five mAbs that bound each of the seven subtypes. Three scFv binding non-overlapping epitopes were converted to IgG that had KD for the different BoNT/F subtypes ranging from 2.2×10-8 M to 1.47×10-12 pM. An equimolar combination of the mAbs was able to potently neutralize BoNT/F1, F2, F4 and F7 in the mouse neutralization assay. The mAbs have potential utility as diagnostics capable of recognizing the known BoNT/F subtypes and could be developed as antitoxins to prevent and treat type F botulism.
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Yao G, Lam KH, Perry K, Weisemann J, Rummel A, Jin R. Crystal Structure of the Receptor-Binding Domain of Botulinum Neurotoxin Type HA, Also Known as Type FA or H. Toxins (Basel) 2017; 9:toxins9030093. [PMID: 28282873 PMCID: PMC5371848 DOI: 10.3390/toxins9030093] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/03/2017] [Accepted: 03/04/2017] [Indexed: 01/02/2023] Open
Abstract
Botulinum neurotoxins (BoNTs), which have been exploited as cosmetics and muscle-disorder treatment medicines for decades, are well known for their extreme neurotoxicity to humans. They pose a potential bioterrorism threat because they cause botulism, a flaccid muscular paralysis-associated disease that requires immediate antitoxin treatment and intensive care over a long period of time. In addition to the existing seven established BoNT serotypes (BoNT/A–G), a new mosaic toxin type termed BoNT/HA (aka type FA or H) was reported recently. Sequence analyses indicate that the receptor-binding domain (HC) of BoNT/HA is ~84% identical to that of BoNT/A1. However, BoNT/HA responds differently to some potent BoNT/A-neutralizing antibodies (e.g., CR2) that target the HC. Therefore, it raises a serious concern as to whether BoNT/HA poses a new threat to our biosecurity. In this study, we report the first high-resolution crystal structure of BoNT/HA-HC at 1.8 Å. Sequence and structure analyses reveal that BoNT/HA and BoNT/A1 are different regarding their binding to cell-surface receptors including both polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Furthermore, the new structure also provides explanations for the ~540-fold decreased affinity of antibody CR2 towards BoNT/HA compared to BoNT/A1. Taken together, these new findings advance our understanding of the structure and function of this newly identified toxin at the molecular level, and pave the way for the future development of more effective countermeasures.
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Affiliation(s)
- Guorui Yao
- Department of Physiology & Biophysics, University of California, Irvine, CA 92697, USA.
| | - Kwok-Ho Lam
- Department of Physiology & Biophysics, University of California, Irvine, CA 92697, USA.
| | - Kay Perry
- NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Building 436E, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439, USA.
| | - Jasmin Weisemann
- Institut für Toxikologie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - Rongsheng Jin
- Department of Physiology & Biophysics, University of California, Irvine, CA 92697, USA.
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29
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Peck MW, Smith TJ, Anniballi F, Austin JW, Bano L, Bradshaw M, Cuervo P, Cheng LW, Derman Y, Dorner BG, Fisher A, Hill KK, Kalb SR, Korkeala H, Lindström M, Lista F, Lúquez C, Mazuet C, Pirazzini M, Popoff MR, Rossetto O, Rummel A, Sesardic D, Singh BR, Stringer SC. Historical Perspectives and Guidelines for Botulinum Neurotoxin Subtype Nomenclature. Toxins (Basel) 2017; 9:toxins9010038. [PMID: 28106761 PMCID: PMC5308270 DOI: 10.3390/toxins9010038] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 01/04/2017] [Accepted: 01/07/2017] [Indexed: 11/26/2022] Open
Abstract
Botulinum neurotoxins are diverse proteins. They are currently represented by at least seven serotypes and more than 40 subtypes. New clostridial strains that produce novel neurotoxin variants are being identified with increasing frequency, which presents challenges when organizing the nomenclature surrounding these neurotoxins. Worldwide, researchers are faced with the possibility that toxins having identical sequences may be given different designations or novel toxins having unique sequences may be given the same designations on publication. In order to minimize these problems, an ad hoc committee consisting of over 20 researchers in the field of botulinum neurotoxin research was convened to discuss the clarification of the issues involved in botulinum neurotoxin nomenclature. This publication presents a historical overview of the issues and provides guidelines for botulinum neurotoxin subtype nomenclature in the future.
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Affiliation(s)
| | - Theresa J Smith
- Molecular and Translational Sciences Division, United States Army Medical Institute of Infectious Diseases, Fort Detrick, MD 21702, USA.
| | - Fabrizio Anniballi
- National Reference Centre for Botulism, Istituto Superiore di Sanita, Rome 299-00161, Italy.
| | - John W Austin
- Bureau of Microbial Hazards, Health Canada, Ottawa, ON K1A 0K9, Canada.
| | - Luca Bano
- Istituto Zooprofilattico Sperimentale delle Venezie, Treviso 31020, Italy.
| | - Marite Bradshaw
- Department of Bacteriology, University of Wisconsin, Madison, WI 53706, USA.
| | - Paula Cuervo
- Área de Microbiología, Departamento de Patología, Universidad Nacional de Cuyo, Mendoza 450001, Argentina.
| | - Luisa W Cheng
- Foodborne Toxin Detection and Prevention Research Unit, Western Regional Research Center, U.S. Department of Agriculture, Albany, CA 94710, USA.
| | - Yagmur Derman
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki 00014, Finland.
| | | | - Audrey Fisher
- Applied Physics Laboratory, Johns Hopkins University, Baltimore, MD 21218, USA.
| | - Karen K Hill
- Los Alamos National Laboratories, Los Alamos, NM 87545, USA.
| | - Suzanne R Kalb
- National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
| | - Hannu Korkeala
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki 00014, Finland.
| | - Miia Lindström
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki 00014, Finland.
| | - Florigio Lista
- Army Medical and Veterinary Research Center, Rome 00184, Italy.
| | - Carolina Lúquez
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA.
| | - Christelle Mazuet
- Institut Pasteur, Bactéries anaérobies et Toxines, Paris 75015, France.
| | - Marco Pirazzini
- Biomedical Sciences Department, University of Padova, Padova 35131, Italy.
| | - Michel R Popoff
- Institut Pasteur, Bactéries anaérobies et Toxines, Paris 75015, France.
| | - Ornella Rossetto
- Biomedical Sciences Department, University of Padova, Padova 35131, Italy.
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover 30623, Germany.
| | - Dorothea Sesardic
- National Institute for Biological Standards and Control, a Centre of Medicines and Healthcare Products Regulatory Agency, Hertfordshire EN6 3QG, UK.
| | - Bal Ram Singh
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA.
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Abstract
C. botulinum Groups I and II form botulinum neurotoxin and cause foodborne botulism. Increased knowledge of C. botulinum Group I and II genomes and neurotoxin diversity. Impact on food safety via improved surveillance and tracing/tracking during outbreaks. New insights into C. botulinum biology, food chain transmission, evolution.
The deadly botulinum neurotoxin formed by Clostridium botulinum is the causative agent of foodborne botulism. The increasing availability of C. botulinum genome sequences is starting to allow the genomic diversity of C. botulinum Groups I and II and their neurotoxins to be characterised. This information will impact on microbiological food safety through improved surveillance and tracing/tracking during outbreaks, and a better characterisation of C. botulinum Groups I and II, including the risk presented, and new insights into their biology, food chain transmission, and evolution.
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Yao G, Zhang S, Mahrhold S, Lam KH, Stern D, Bagramyan K, Perry K, Kalkum M, Rummel A, Dong M, Jin R. N-linked glycosylation of SV2 is required for binding and uptake of botulinum neurotoxin A. Nat Struct Mol Biol 2016; 23:656-62. [PMID: 27294781 PMCID: PMC5033645 DOI: 10.1038/nsmb.3245] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/13/2016] [Indexed: 02/01/2023]
Abstract
Botulinum neurotoxin serotype A1 (BoNT/A1) is one of the most dangerous potential bioterrorism agents, and exerts its action by invading motoneurons. It is also a licensed drug widely used for medical and cosmetic applications. Here we report a 2.0 Å resolution crystal structure of BoNT/A1 receptor-binding domain in complex with its neuronal receptor, the glycosylated human SV2C. We find that the neuronal tropism of BoNT/A1 requires recognition of both the peptide moiety and an N-linked glycan on SV2. This N-glycan—conserved in all SV2 isoforms across vertebrates—is essential for BoNT/A1 binding to neurons and its potent neurotoxicity. The glycan-binding interface on SV2 is targeted by a human BoNT/A1-neutralizing antibody currently licensed as an anti-botulism drug. Our studies reveal a new paradigm of host-pathogen interactions, in which pathogens exploit conserved host post-translational modifications to achieve highly specific receptor binding while also tolerating genetic changes across multiple isoforms of receptors.
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Affiliation(s)
- Guorui Yao
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, California, USA
| | - Sicai Zhang
- Department of Urology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA.,Department of Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Stefan Mahrhold
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Kwok-Ho Lam
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, California, USA
| | - Daniel Stern
- Centre for Biological Threats and Special Pathogens-Biological Toxins (ZBS3), Robert Koch-Institut, Berlin, Germany
| | - Karine Bagramyan
- Department of Molecular Immunology, Beckman Research Institute of City of Hope, Duarte, California, USA
| | - Kay Perry
- NE-CAT, Argonne National Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Argonne, Illinois, USA
| | - Markus Kalkum
- Department of Molecular Immunology, Beckman Research Institute of City of Hope, Duarte, California, USA
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA.,Department of Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Rongsheng Jin
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, California, USA
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32
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Ambrose EA. Botulinum Neurotoxin, Tetanus Toxin, and Anthrax Lethal Factor Countermeasures. TOPICS IN MEDICINAL CHEMISTRY 2016. [DOI: 10.1007/7355_2016_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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