title: Bivalent recombinant vaccine for botulinum neurotoxin types A and B based on a polypeptide comprising their effector and translocation domains that is protective against the predominant A and B subtypes.
abstract: The botulinum neurotoxins (BoNTs) are a large family of extremely potent, neuroparalytic, dichain proteins which act at the peripheral nervous system. The wide genetic diversity observed with this neurotoxin family poses a significant challenge for the development of an effective botulinum vaccine. The present study describes a vaccine development platform based on protein fragments representing the N-terminal two-thirds of each toxin molecule. These fragments, designated LH(N), comprise the light chain and translocation domains of each neurotoxin and are devoid of any neuron-binding activity. Using codon-optimized genes, LH(N) fragments derived from BoNT serotypes A and B were expressed in Escherichia coli in high yield with >1 g of purified, soluble fragment recoverable from 4.5 liter-scale fermentations. The protective efficacy of LH(N)/A was significantly enhanced by treatment with formaldehyde, which induced intramolecular cross-linking but virtually no aggregation of the fragment. A single immunization of the modified fragment protected mice from challenge with a 10(3) 50% lethal dose (LD(50)) of BoNT/A(1) with an 50% effective dose (ED(50)) of 50 ng of the vaccine. In similar experiments, the LH(N)/A vaccine was shown to protect mice against challenge with BoNT/A subtypes A(1), A(2), and A(3), which is the first demonstration of single-dose protection by a vaccine against the principal toxin subtypes of BoNT/A. The LH(N)/B vaccine was also highly efficacious, giving an ED(50) of approximately 140 ng to a challenge of 10(3) LD(50) of BoNT/B(1). In addition, LH(N)/B provided single-dose protection in mice against BoNT/B(4) (nonproteolytic toxin subtype).
authors.affiliation: Health Protection Agency, Porton Down, Salisbury, Wilts, United Kingdom.
authors.forename: Clifford
authors.initials: C
authors.lastname: Shone
authors.forename: Heidi
authors.initials: H
authors.lastname: Agostini
authors.forename: Joanna
authors.initials: J
authors.lastname: Clancy
authors.forename: Mili
authors.initials: M
authors.lastname: Gu
authors.forename: Huei-Hsiung
authors.initials: HH
authors.lastname: Yang
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Chu
authors.forename: Virginia
authors.initials: V
authors.lastname: Johnson
authors.forename: Makie
authors.initials: M
authors.lastname: Taal
authors.forename: Joanna
authors.initials: J
authors.lastname: McGlashan
authors.forename: John
authors.initials: J
authors.lastname: Brehm
authors.forename: Xiaomi
authors.initials: X
authors.lastname: Tong
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology*; D001905:Botulinum Toxins / Q000235:genetics / Q000276:immunology*; D019274:Botulinum Toxins, Type A / Q000235:genetics / Q000276:immunology*; D001906:Botulism / Q000517:prevention & control*; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D051379:Mice; D008958:Models, Molecular; D016019:Survival Analysis; D014614:Vaccines, Synthetic / Q000235:genetics / Q000276:immunology
chemical_list: D001428:Bacterial Vaccines; D014614:Vaccines, Synthetic; C096323:rimabotulinumtoxinB; D001905:Botulinum Toxins; D019274:Botulinum Toxins, Type A