Dissecting the contributions of Clostridium perfringens type C toxins to lethality in the mouse intravenous injection model
Dissecting the contributions of Clostridium perfringens type C toxins to lethality in the mouse intravenous injection model
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DOI：
10.1128/iai.00534-06
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发表时间：
2006-09-01
影响因子：
3.1
通讯作者：
McClane, Bruce A.
中科院分区：
文献类型：
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作者：
Fisher, Derek J.;Fernandez-Miyakawa, Mariano E.;McClane, Bruce A.
革兰氏阳性厌氧菌产气荚膜梭菌产生大量毒素，这些毒素导致人类和家畜的组织毒性和肠道感染，包括肠毒血症。C型产气荚膜梭菌分离株在家畜中引起快速致死性疾病和在人类中引起坏死性肠炎，其含有α毒素（plc）、产气荚膜梭菌溶素O（pfoA）β毒素（cpb）以及有时β 2毒素（cpb 2）和/或肠毒素（cpe）的基因。由于C型诱导的疾病的经济影响，家畜通常用粗制C型类毒素（从灭活的培养物上清液制备）或类毒素/类毒素疫苗接种，并且不清楚这些疫苗中存在的哪种毒素实际上增强了保护性免疫应答。为了改进C型疫苗，评估C型上清液中存在的每种毒素对致死率的贡献将是有帮助的。为了解决这个问题，我们调查了大量的C型分离株，以确定它们的产毒能力。当后期对数期营养培养上清液进行了分析，通过定量Western印迹或活性测定，大多数C型分离株产生至少三个致命的毒素，α毒素，β毒素，和产气荚膜梭菌溶素O，和几个分离株还产生β 2毒素。在小鼠静脉注射模型中，β毒素被鉴定为C型对数期晚期培养物上清液中存在的主要致死因子。该结论基于单克隆抗体中和研究和回归分析，其中将α毒素、β毒素、产气荚膜梭菌溶素O和β 2毒素产生的水平与致死率进行了比较。总的来说，我们的研究结果突出了β毒素对C型诱导的毒血症的重要性。
The gram-positive anaerobe Clostridium perfringens produces a large arsenal of toxins that are responsible for histotoxic and enteric infections, including enterotoxemias, in humans and domestic animals. C perfringens type C isolates, which cause rapidly fatal diseases in domestic animals and enteritis necroticans in humans, contain the genes for alpha toxin (plc), perfringolysin O (pfoA) beta toxin (cpb), and sometimes beta2 toxin (cpb2) and/or enterotoxin (cpe). Due to the economic impact of type C-induced diseases, domestic animals are commonly vaccinated with crude type C toxoid (prepared from inactivated culture supernatants) or bacterin/ toxoid vaccines, and it is not clear which toxin(s) present in these vaccines actually elicits the protective immune response. To improve type C vaccines, it would be helpful to assess the contribution of each toxin present in type C supernatants to lethality. To address this issue, we surveyed a large collection of type C isolates to determine their toxin-producing abilities. When late-log-phase vegetative culture supernatants were analyzed by quantitative Western blotting or activity assays, most type C isolates produced at least three lethal toxins, alpha toxin, beta toxin, and perfringolysin O, and several isolates also produced beta2 toxin. In the mouse intravenous injection model, beta toxin was identified as the main lethal factor present in type C late-log-phase culture supernatants. This conclusion was based on monoclonal antibody neutralization studies and regression analyses in which the levels of alpha toxin, beta toxin, perfringolysin O, and beta2 toxin production were compared with lethality. Collectively, our results highlight the importance of beta toxin for type C-induced toxemia.