...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Infection and immunity >Interrelationships between digestive proteolytic activities and production and quantitation of toxins in pseudomembranous colitis induced by Clostridium difficile in gnotobiotic mice.
【24h】

Interrelationships between digestive proteolytic activities and production and quantitation of toxins in pseudomembranous colitis induced by Clostridium difficile in gnotobiotic mice.

机译：难辨梭状芽胞杆菌致盲小鼠的消化膜蛋白水解活性与伪膜性结肠炎中毒素产生和定量之间的相互关系。

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Clostridium difficile pathogenicity is related to in vivo production of toxins, and it is of great interest to detect toxins produced in biological samples. Several reports have shown that proteases in stools interfere with immunological methods for quantitation of toxin A. The purpose of this work was to estimate the relationship between the proteases and the C. difficile toxins produced in a gnotobiotic mouse model of pseudomembranous cecitis. Cecal proteolytic activities hydrolyzed toxin A, and immunoglobulin G bound to the microtiter plate used in immunoassays. This interference could be blocked by the addition of trypsin inhibitor to the samples. The ability of soluble toxin A to bind to bound antibodies in an enzyme-linked immunosorbent assay was not affected by the proteases, but the biological activity was reduced 100-fold. The cytotoxicity of toxin B was not modified by proteolytic activity treatment. Mice inoculated with a low toxin A-producing strain of C. difficile did not died, and no modulation of proteolytic activities occurred. After inoculation with the lethal VPI strain of C. difficile, toxins A and B reached maximum levels in the ceca at 12 h postinfection. At this time, the proteolytic activities did not decrease from the levels seen at zero time. Mice died within 2 days. At this time (about 32 postinfection), proteolytic activities were sharply decreased in the lower parts of the digestive tracts. The findings that serum inhibited the proteases and that there was a 100-fold increase in serum-derived mouse immunoglobulins in the lumen as the C. difficile infection progressed suggest that the decrease in protease activity in the lower digestive tract may be related to the exudation of serum from the inflammation process.
机译：艰难梭菌的致病性与体内毒素的产生有关，检测生物样品中产生的毒素非常重要。几篇报道表明，粪便中的蛋白酶干扰了定量A毒素的免疫学方法。这项工作的目的是评估蛋白酶与假膜性盲肠炎的致病小鼠模型中产生的艰难梭菌毒素之间的关系。盲肠的蛋白水解活性水解了毒素A，而免疫球蛋白G则与免疫测定中使用的微量滴定板结合。可以通过在样品中添加胰蛋白酶抑制剂来阻止这种干扰。在酶联免疫吸附测定中，可溶性毒素A与结合抗体结合的能力不受蛋白酶的影响，但生物学活性降低了100倍。蛋白水解活性处理不能改变毒素B的细胞毒性。接种有低毒素A的艰难梭菌菌株的小鼠没有死亡，也没有发生蛋白水解活性的调节。用致死梭状芽孢杆菌的致死性VPI菌株接种后，毒素A和B在感染后12小时的盲肠中达到最高水平。此时，蛋白水解活性没有从零时的水平降低。小鼠在两天内死亡。这时（感染后约32次），消化道下部的蛋白水解活性急剧下降。血清抑制蛋白酶的发现，随着艰难梭菌感染的进展，管腔中的血清小鼠免疫球蛋白增加了100倍，这表明下消化道蛋白酶活性的降低可能与分泌物有关来自炎症过程的血清。

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号