XXXX homeostasis at the host vibrio interface: lessons from intracellular vibrio transcriptomics.

@entity7155 @entity137 @entity920 @entity6796
Recent studies revealed that several vibrio species have evolved the capacity to survive inside host cells. However, it is still often ignored if intracellular stages are required for pathogenicity. Virulence of @entity7155 , a strain pathogenic for @entity6796 oysters, depends on entry into hemocytes, the oyster immune cells. We investigated here the mechanisms of @entity7155 intracellular survival and their consequences on the host-pathogen interaction. Entry and survival inside hemocytes were required for @entity7155 -driven cytolysis of hemocytes, both in vivo and in vitro. @entity7155 intracellular stages showed a profound boost in metabolic activity and a major transcription of antioxidant and @entity920 detoxification genes, as revealed by RNA sequencing. @entity7155 isogenic mutants showed that resistance to oxidative stress and @entity920 efflux are two main functions required for vibrio intracellular stages and @entity137 to hemocytes. @entity920 efflux was also essential for host colonization and virulence in vivo. Altogether, our results identify @entity920 resistance as a major mechanism to resist killing by phagocytes, induce cytolysis of immune cells and colonize oysters. Selection of such resistance traits could arise from vibrio interactions with @entity920 -rich environmental niches including marine invertebrates, which favour the emergence of pathogenic vibrios resistant to intraphagosomal killing across animal species.
