PDF(Pubmed)
Abstract：
The effects of intestinal microflora on extraintestinal immune response by intestinal cytokines and metabolites have been documented, but whether intestinal microbes stimulate serum antibody generation is unknown. Here, serum antibodies against 69 outer membrane proteins of Escherichia coli, a dominant bacterium in the human intestine, are detected in 141 healthy individuals of varying ages. Antibodies against E. coli outer membrane proteins are determined in all serum samples tested, and frequencies of antibodies to five outer membrane proteins (OmpA, OmpX, TsX, HlpA, and FepA) are close to 100%. Serum antibodies against E. coli outer membrane proteins are further validated by Western blot and bacterial pull-down. Moreover, the present study shows that OstA, HlpA, Tsx, NlpB, OmpC, YfcU, and OmpA provide specific immune protection against pathogenic E. coli, while HlpA and OmpA also exhibit cross-protection against Staphylococcus aureus infection. These finding indicate that intestinal E. coli activate extraintestinal antibody responses and provide anti-infective immunity.
摘要：
肠道菌群对肠道细胞因子和代谢产物肠外免疫反应的影响已被证明。但是肠道微生物是否刺激血清抗体生成是未知的。这里,针对69个大肠杆菌外膜蛋白的血清抗体，人类肠道中的优势细菌，在141个不同年龄的健康个体中检测到。在所有测试的血清样品中测定抗大肠杆菌外膜蛋白的抗体，和五种外膜蛋白(OmpA，OmpX,TsX,HlpA,和FepA）接近100%。通过Western印迹和细菌下拉法进一步验证针对大肠杆菌外膜蛋白的血清抗体。此外，目前的研究表明，Osta,HlpA,Tsx,NlpB,OmpC,YfcU,和OmpA提供针对致病性大肠杆菌的特异性免疫保护，而HlpA和OmpA也表现出对金黄色葡萄球菌感染的交叉保护。这些发现表明肠大肠杆菌激活肠外抗体应答并提供抗感染免疫。
