Salmonella adheres to the microvilli of intestinal mucosal epithelial cells. Salmonella invasins trigger actin polymerization and depolymerization. (This pseuodpod formation is sometimes referred to as membrane ruffling.) This causes the epithelial cell to form pseudopods that engulf the Salmonella and place it in an endocytic vacuole. The Salmonella replicate within the endocytic vacuole and are subsequently released from the cell.