Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
FEMS Microbiol Lett. 2010 Feb;303(2):156-62. doi: 10.1111/j.1574-6968.2009.01878.x. Epub 2009 Dec 7.
Binding of meningitis-causing Escherichia coli K1 to human brain microvascular endothelial cells (HBMEC) contributes to traversal of the blood-brain barrier, which occurs in part by the mannose-sensitive binding of FimH. In this study, we showed that FimH also binds to HBMEC, independent of mannose, and identified ATP synthase beta-subunit and actin proteins from the surface biotinylated HBMEC as the mannose-insensitive binding targets for FimH. Co-immunoprecipitation experiments in the presence of alpha-methyl mannose verified the binding of FimH to ATP synthase beta-subunit of HBMEC. ATP synthase beta-subunit antibody decreased E. coli K1 binding to HBMEC in the presence of alpha-methyl mannose. Taken together, these findings demonstrate that FimH of E. coli K1 binds to HBMEC in both mannose-sensitive and -insensitive manner.
导致脑膜炎的大肠杆菌 K1 与人类脑微血管内皮细胞 (HBMEC) 的结合有助于血脑屏障的穿透，这部分是通过 FimH 的甘露糖敏感结合来实现的。在这项研究中，我们表明 FimH 也可以独立于甘露糖与 HBMEC 结合，并确定了来自表面生物素化 HBMEC 的 ATP 合酶β亚基和肌动蛋白蛋白是 FimH 的甘露糖非敏感结合靶标。在存在 α-甲基甘露糖的情况下进行的共免疫沉淀实验证实了 FimH 与 HBMEC 的 ATP 合酶β亚基的结合。ATP 合酶β亚基抗体在存在 α-甲基甘露糖的情况下降低了大肠杆菌 K1 与 HBMEC 的结合。总之，这些发现表明大肠杆菌 K1 的 FimH 以甘露糖敏感和非敏感的方式与 HBMEC 结合。
