Internalization of Helicobacter pylori by Epithelial Cells via a Cholesterol‐dependent Pathway

Lipid rafts are cellular membrane microdomains, composed mainly of phospholipids, sphingolipids, and cholesterol. These microdomains are not only dynamic structures on cell membrane but also provide amplified signalings for the activation of the cells. Recent studies revealed that many pathogens might favor interact to lipid rafts as a potential route to enter host cells. Investigating the role of host cell lipid rafts playing in the invasion of H. pylori into epithelial cells would contribute to our understanding of the pathogenesis of H. pylori . We identified that internalization of H. pylori was associated with lipid rafts, while adherence was not. We also observed that accumulation of cholesterol at the sites of H. pylori attachment. Furthermore, we demonstrated that VacA, CagA, and BabA2 were able to associate with lipid rafts and have high efficiency for providing the clustering of the rafts. We suggested that this effect would generate a platform for the entry of H. pylori to AGS cells during the infection process. Our results indicate that VacA, CagA, and BabA2 may play important roles for interaction with lipid rafts in the infection process of AGS cells.