Host signal transduction and endocytosis of Campylobacter jejuni.

Caveolae are plasma membrane invaginations found in a variety of mammalian cells and are implicated in clathrin-independent endocytosis and signal transduction. Here we show that pretreatment of Caco-2 cell monolayers with filipin III, which disrupts caveolae by chelating cholesterol, significantly reduces the ability of Campylobacter jejuni to enter these cells. Furthermore inhibitors of host protein tyrosine phosphorylation, the phosphatidylinositol-3 kinase (Pl 3-kinase) inhibitor wortmannin, and cholera toxin, all significantly reduced invasion of Caco-2 cells by C. jejuni.