AUTHOR=Hatayama Sho , Shimohata Takaaki , Amano Sachie , Kido Junko , Nguyen Anh Q. , Sato Yuri , Kanda Yuna , Tentaku Aya , Fukushima Shiho , Nakahashi Mutsumi , Uebanso Takashi , Mawatari Kazuaki , Takahashi Akira 

TITLE=Cellular Tight Junctions Prevent Effective Campylobacter jejuni Invasion and Inflammatory Barrier Disruption Promoting Bacterial Invasion from Lateral Membrane in Polarized Intestinal Epithelial Cells

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=8

YEAR=2018

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2018.00015

DOI=10.3389/fcimb.2018.00015

ISSN=2235-2988

ABSTRACT=<p><italic>Campylobacter jejuni</italic> invasion is closely related to <italic>C. jejuni</italic> pathogenicity. The intestinal epithelium contains polarized epithelial cells that form tight junctions (TJs) to provide a physical barrier against bacterial invasion. Previous studies indicated that <italic>C. jejuni</italic> invasion of non-polarized cells involves several cellular features, including lipid rafts. However, the dynamics of <italic>C. jejuni</italic> invasion of polarized epithelial cells are not fully understood. Here we investigated the interaction between <italic>C. jejuni</italic> invasion and TJ formation to characterize the mechanism of <italic>C. jejuni</italic> invasion in polarized epithelial cells. In contrast to non-polarized epithelial cells, <italic>C. jejuni</italic> invasion was not affected by depletion of lipid rafts in polarized epithelial cells. However, depletion of lipid rafts significantly decreased <italic>C. jejuni</italic> invasion in TJ disrupted cells or basolateral infection and repair of cellular TJs suppressed lipid raft-mediated <italic>C. jejuni</italic> invasion in polarized epithelial cells. In addition, pro-inflammatory cytokine, TNF-α treatment that induce TJ disruption promote <italic>C. jejuni</italic> invasion and lipid rafts depletion significantly reduced <italic>C. jejuni</italic> invasion in TNF-α treated cells. These data demonstrated that TJs prevent <italic>C. jejuni</italic> invasion from the lateral side of epithelial cells, where they play a main part in bacterial invasion and suggest that <italic>C. jejuni</italic> invasion could be increased in inflammatory condition. Therefore, maintenance of TJs integrity should be considered important in the development of novel therapies for <italic>C. jejuni</italic> infection.</p>