Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan.
Jpn J Infect Dis. 2012;65(2):138-45.
Clostridium botulinum produces large complex toxins, which include botulinum neurotoxin (BoNT) and auxiliary non-toxic proteins. We prepared monoclonal antibodies (mAbs) from mice that were immunized several times with BoNT/A after basal immunization with toxoid. We then examined the reactivities of these mAbs to BoNT and toxoid and showed that some mAbs reacted to only BoNT. This result indicates that the antigenicity of BoNT/A partially disappeared with formalin treatment. Some mAbs that specifically recognized either BoNT/A1 or BoNT/A2 were considered useful as detection antibodies specific for the BoNT/A subtype. Results of a neutralizing test with mAbs against either BoNT/A1 or BoNT/A2 showed that neutralizing antibody recognition sites were present in the light chain, heavy chain (N-terminal half), and heavy chain (C-terminal half) domains. Investigation of the different binding capabilities of the mAbs to BoNT and the complex toxin by immunoprecipitation suggested that the light chain of BoNT is exposed at the molecular surface of the complex toxin since there was no difference in the binding of light chain-specific mAb to BoNT and the complex toxin. The heavy chain is related to BoNT binding to non-toxic components, because the reactivity of the heavy chain to some mAbs was influenced by non-toxic components.
肉毒梭菌产生大型复杂毒素，包括肉毒神经毒素（BoNT）和辅助无毒蛋白。我们用 BoNT/A 免疫基础免疫后的小鼠多次免疫，制备了单克隆抗体（mAbs）。然后，我们检查了这些 mAbs 对 BoNT 和类毒素的反应性，并表明一些 mAbs 仅对 BoNT 有反应。这一结果表明，BoNT/A 的抗原性在福尔马林处理后部分消失。一些特异性识别 BoNT/A1 或 BoNT/A2 的 mAbs 被认为是有用的 BoNT/A 亚型检测抗体。针对 BoNT/A1 或 BoNT/A2 的 mAbs 的中和试验结果表明，中和抗体识别位点存在于轻链、重链（N 端半）和重链（C 端半）结构域中。通过免疫沉淀研究 mAbs 对 BoNT 和复合毒素的不同结合能力表明，BoNT 的轻链在复合毒素的分子表面暴露，因为针对 BoNT 和复合毒素的轻链特异性 mAb 的结合没有差异。重链与 BoNT 与无毒成分的结合有关，因为重链对一些 mAbs 的反应性受到无毒成分的影响。
