Interaction of E. coli Invasion Gene Deletion Mutants with Human Brain Microvascular Endothelial Cell

Abstract: IbeA， ibeB and ibeC are important genes associated with E.coli K1 invasion to human brain microvascular endothelial cell (HBMEC)， but the role of each gene in invasion process is not clear. The main purpose of this study is to make a preliminary conclusion of the function of each gene. We had HBMEC interacted with the invasion gene (IbeA， ibeB and ibeC) deletion mutants of E.coli， meanwhile the HBMEC interacted with wild type E.coli is as positive control .The invasion rate of each mutant ， HBMEC cytoskeleton and tight junction changes were studied. In the invasion test， each mutant of E.coli showed remarkable low invasion rate to HBMEC in contrast to that of wild E.coli. HBMEC interacted with IbeA deletion mutant showed distinct change in cytoskeleton just same as the positive control， while， HBMEC interacted with ibeB ， ibeC deletion mutants respectively showed relatively small in cytoskeletal change in contrast to negative control HBMEC. In tight junction test， HBMEC interacted with IbeA deletion mutant showed the same result as positive control HBMEC in which tight junction is heavily disturbed， HBMEC interacted with ibeB， ibeC deletion mutants respectively showed relatively small tight junction disturbance in contrast to negative control HBMEC . Taken together， we can propose that the IbeA not play any role in cytoskeleton and tight junction regulation; ibeB and ibeC ， on the contrary， play an important role in both processes .

CSTR: 32200.14.cjcb.2005.03.0019