Factors that influence the interaction of Campylobacter jejuni with cultured mammalian cells

Although Campylobacter jejuni is now recognised as a common enteric pathogen, the mechanisms by which this organism produces enteritis remain ill-defined. It has been proposed that its abilities to adhere to and enter epithelial cells represent properties essential to virulence. However, the characteristics of these interactions and factors that may influence the association of C. jejuni with epithelial cells are incompletely described. We have determined that the ability of C. jejuni to bind to epithelial cell lines in vitro is significantly affected by the growth temperature and growth stage of the bacteria, but not by growth-medium composition. Binding of C. jejuni to cultured cells is not affected by temperature or phylogenetic origin of the target cell, and exhibits a non-uniform or patchy distribution. In contrast, internalisation is markedly diminished at low temperature, appears to involve active invagination of the target cell membrane via pseudopod formation, and is maximal when cells of human origin are employed.