Thermostable direct hemolysin of Vibrio parahaemolyticus induces morphological changes and disrupts actin in cultured human epithelial cells

The effects of thermostable direct hemolysin (TDH) of Vibrio parahaemolyticus on HeLa and Intestine 407 cells were evaluated. The both cells were unexposed and exposed to TDH in the cytotoxic conditions. As assessed by fluorescent actin-staining, TDH-exposed cells showed morphological changes including detachment of cells from their neighbors, apparent loss of cytoplasm with shrinkage of most of the cells. Furthermore, TDH treatment of cells resulted in redistribution of actin with loss of stress fibers, a floccular staining pattern, cellular membrane blebbing, and cell rounding. The actin redistribution was time dependent. We reported here that TDH can induce morphological and cytoskeletal changes in cultured human epithelial cells.