Binary toxin-producing, large clostridial toxin-negative Clostridium difficile strains are enterotoxic but do not cause disease in hamsters
Binary toxin-producing, large clostridial toxin-negative Clostridium difficile strains are enterotoxic but do not cause disease in hamsters
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DOI：
10.1086/501368
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发表时间：
2006-04-15
影响因子：
6.4
通讯作者：
Johnson, S
中科院分区：
文献类型：
--
作者：
Geric, B;Carman, RJ;Johnson, S
二元毒素CDT或其基因已经在艰难梭菌的一些菌株中被鉴定，所述艰难梭菌菌株也产生大梭菌毒素A和B（A+B+CDT+），包括在美国和加拿大新认识到的流行菌株。为了研究二元毒素单独作用的效果，我们鉴定了4个二元毒素CDT阳性（A（-）B（-）CDT（+））C。艰难菌株与其他梭菌二元毒素不同，二元毒素CDT需要外源胰蛋白酶激活。所有A（-）B（-）CDT（+）菌株的上清液在浓缩和胰蛋白酶消化后在兔回肠袢试验中引起显著的液体蓄积。此外，回肠袢反应被针对其他二元产毒素梭菌产生的抗血清中和。克林霉素处理的仓鼠与这些菌株的挑战导致殖民，但不是腹泻或死亡。二元毒素CDT可能在C的发病机制中对毒素A和B起辅助作用。但其本身可能不足以引起疾病。
Binary toxin CDT or its genes have been identified in some strains of Clostridium difficile that also produce the large clostridial toxins, toxins A and B (A+B+CDT+), including a newly recognized epidemic strain in the United States and Canada. To study the effects of binary toxin alone, we characterized 4 binary toxin CDT positive only ( A(-)B(-)CDT(+)) C. difficile strains. Unlike other clostridial binary toxins, binary toxin CDT required exogenous trypsin for activation. Supernatants from all A(-)B(-)CDT(+) strains caused marked fluid accumulation in the rabbit ileal loop assay after concentration and trypsinization. In addition, the ileal loop response was neutralized by antisera raised against other binary toxin-producing clostridia. Challenge of clindamycin-treated hamsters with these strains resulted in colonization but not diarrhea or death. Binary toxin CDT may play an adjunctive role to toxins A and B in the pathogenesis of C. difficile-associated disease but by itself may not be sufficient to cause disease.