Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia 22908-1363, USA.
Infect Immun. 2010 Apr;78(4):1475-81. doi: 10.1128/IAI.00669-09. Epub 2010 Jan 19.
Entamoeba histolytica is the agent of amebic colitis. In this work we examined the intestinal NF-kappaB response to this parasite. Using an enzyme-linked immunosorbent assay (ELISA) and an electrophoretic mobility shift assay, we found that the NF-kappaB subunit p50 predominated in nuclear extracts of whole cecal tissue and of isolated crypts from mice inoculated with E. histolytica. p50 was protective, since C57BL/6 and 129 mice in which there was targeted deletion of this subunit were more susceptible to E. histolytica infection as measured by culture results, cecal parasite ELISA results, and/or histologic scores. The transepithelial electrical resistance of cecal explants from C57BL/6 and 129 p50 knockout mice decreased markedly in response to the parasite compared with the transepithelial electrical resistance of their wild-type counterparts, suggesting that a protective function of p50 was present in the epithelium itself. This work shows that NF-kappaB activity, particularly activity of the p50 subunit, is one factor that contributes to resistance of the gut to E. histolytica infection.
溶组织内阿米巴是阿米巴结肠炎的病原体。在这项工作中，我们研究了肠道 NF-κB 对这种寄生虫的反应。通过酶联免疫吸附测定（ELISA）和电泳迁移率变动分析，我们发现 NF-κB 亚基 p50 在接种溶组织内阿米巴的小鼠整个盲肠组织和分离的隐窝的核提取物中占优势。p50 具有保护作用，因为靶向缺失该亚基的 C57BL/6 和 129 小鼠对溶组织内阿米巴的感染更为敏感，这可以通过培养结果、盲肠寄生虫 ELISA 结果和/或组织学评分来衡量。与野生型相比，来自 C57BL/6 和 129 p50 基因敲除小鼠的盲肠组织的上皮细胞间电阻在受到寄生虫刺激后明显降低，这表明 p50 在肠上皮本身具有保护作用。这项工作表明，NF-κB 活性，特别是 p50 亚基的活性，是肠道抵抗溶组织内阿米巴感染的一个因素。
