Adherence and Invasion of Aeromonas Caviae to Monolayer Cells

Abstract

Aeromonas species are increasingly being recognised as a significant potential cause of gastro-enteritis. A. hydrophila, A. sobria and A. caviae account for more than 85% of all routine clinical isolates. Recent world-wide investigations have implicated A. caviae as an organism of increasing enteropathogenic importance, especially of children. Adhesion to the intestine followed by the activity of other virulence factors such as toxin production and invasion are probably the most common mechanisms which result in diarrhoea. The use of an in vitro tissue culture assay has shown some strains of Aeromonas to be invasive in HEp-2 cells (Shaw et al., 1995). Qualitative investigation employing electron microscopy and fluorescent staining of intracellular bacteria has also shown Aeromonas species to be invasive in Caco-2 cell monolayers. Strains reported by others to be invasive belong primarily to the species A. sobria, with a smaller proportion belonging to A. hydrophila. With the paucity of information on the invasive potential of this genus; all aspects of Aeromonas adherence and internalisation must warrant further investigation.