Molecular Recognition of Antigen Determinant by Monoclonal Antibody Specific to Neurotoxins from Snake Venoms

点击翻译按钮获取中文摘要

alpha-bungarotoxin was purified from the venom of Bungarus multicinctus. Immunization of mice was achieved by injecting subcutaneously native toxin at two week intervals using the incomplete Freunds' adjuvant into BALB c mice. After the conventional methods, nine hybridomas producing monoclonal antibodies specific to alpha-bungarotoxin were obtained. Large quantity of monoclonal antibody MaB-2311 produced by one of these hybridoma was purified from the ascites fluid of BALB c mice. MaB-2311 inhibited the lethal effect of alpha-bungarotoxin in vivo assay, suggesting that this monoclonal antibody binds to the region specific to neurotoxic activity. Cross reactivity of MaB-2311 was studied using several long neurotoxins, including Toxin B, Toxin III and LS III. Compared with the cross reactivity of these toxins and MaB-2311, and homology of the primary sequences, an antigenic determinat for MaB-2311 was determind to be Ser34-Ser35-Arg36-Gly37-Lys38. The peptide fragment containing this sequence also reacts with MaB-2311, supporting again that the region involving this sequence is an antigenic determinat. Since Arg36 is an essential residue for neurotoxicity, it is reasonable that this monoclonal antibody neutralizes the neurotoxicity of alpha-bungarotoxin. The MaB-2311 producing hybridoma was subsequently cultured in serum free medium so that deuterium labelled amino acids were incorporated into MaB-2311. NMR studies to investigate the molecular recognition of alpha-bungarotoxin and MaB-2311 are now in progress using the deuterium labelled monoclonal antibody and the peptide fragment.