title: Characterization of monoclonal antibodies against Naja naja oxiana neurotoxin I.
abstract: Seven monoclonal antibodies (mAbs) were developed against neurotoxin I (NT-1), a protein from central Asian cobra (Naja naja oxiana) venom which binds specifically to nicotinic acetylcholine receptor (AchR). All of the mAbs cross-reacted with another long-chain post-synaptic neurotoxin, Bungarus multicinctus alpha-bungarotoxin (alpha-BT), but not Naja naja kaouthia alpha-cobratoxin, in an enzyme-linked immunosorbent assay (e.l.i.s.a.). Short-chain post-synaptic neurotoxins like Naja naja atra cobrotoxin, Laticauda semifasciata erabutoxin b, or N. n. oxiana neurotoxin II did not cross-react with the NT-1 mAbs, but an antigen(s) found in Dendroaspis polylepis, Acanthophis antarcticus and Pseudechis australis venoms was immunoreactive. The e.l.i.s.a. readings for dithiothreitol-reduced NT-1 and NT-1 mAbs ranged from 13 to 27% of those for native toxin but reduced alpha-BT was not immunoreactive. Synthetic NT-1 peptides were used in epitope-mapping studies and two, non-contiguous regions (Cys15-Tyr23 and Lys25-Gly33 or Pro17-Lys25 and Asp29-Lys37) were recognized by the NT-1 mAbs. The NT-1 mAbs individually inhibited 31-71% of alpha-BT binding to AchR in vitro and afforded a slight protective effect in vivo with a toxin: antibody mole ratio of 1:1.5. This report is the first to describe mAbs which recognize and protect against a heterologous, long-chain, post-synaptic neurotoxin from snake venom.
authors.affiliation: Toxinology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21702-5011.
authors.forename: B G
authors.initials: BG
authors.lastname: Stiles
authors.forename: F W
authors.initials: FW
authors.lastname: Sexton
authors.forename: S B
authors.initials: SB
authors.lastname: Guest
authors.forename: M A
authors.initials: MA
authors.lastname: Olson
authors.forename: D C
authors.initials: DC
authors.lastname: Hack
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D002038:Bungarotoxins / Q000737:chemistry; D003039:Cobra Neurotoxin Proteins / Q000032:analysis* / Q000276:immunology; D003429:Cross Reactions; D018360:Crystallography, X-Ray; D004546:Elapid Venoms / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D006825:Hybridomas; D007074:Immunoglobulin G; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D009498:Neurotoxins / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid; D012910:Snake Venoms / Q000737:chemistry; D013154:Spleen / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D002038:Bungarotoxins; D003039:Cobra Neurotoxin Proteins; D004546:Elapid Venoms; D007074:Immunoglobulin G; D009498:Neurotoxins; D012910:Snake Venoms; C080422:neurotoxin-1, Naja naja oxiana