Occurrence and expression of virulence-related properties by environmental halophilic Vibrio spp. in in vitro and in vivo systems

Adhesive properties were revealed in 69% of the analysed strains in Caco-2 cells and in 82.7% when using Hep-2 cells. A weak type of adherence seems to be more common. 19.3% of the strains, prevalently represented by V. alginolyticus, appears to produce cytotoxic effects on HeLa cell line while 8.6% exhibits enterotoxic activity. Five of the six V. parahaemolyticus strains results able to produce a thermostable direct haemolysin (TDH), confirmed as the major virulence factor in the pathogenic mechanism of action of this Vibrio species. Because of the strain-specific pathogenicity of most halophilic Vibrio spp., their detection in seafood, giving particular attention to their pathogenicity, is necessary to improve the control of these products.