Effect of encystation on internalized Campylobacter

摘要

Campylobacter spp. causes a significant proportion of diarrhoeal diseases in humans worldwide. Little isrnknown, however, about its ecology and its environmental survival strategies. While the ability ofrnCampylobacter to use the free-living amoeba, Acanthamoeba polyphaga, as an environmental reservoirrnhas been well documented, the majority of this work focuses on the association betweenrnCampylobacter and the trophozoite stage of Acanthamoeba after co-culture, as opposed to the morernenvironmentally robust cyst. To fully understand the level of public health risk resulting from thernassociation between C. jejuni and free-living amoebae, it is important to determine whether C. jejunirnsurvives the stage changes of the amoebae host from trophozoite to cyst and back to trophozoite.rnThrough the use of culture-based and molecular detection techniques, and the use of Mycobacteriumrnavium as a positive control for excystation survival, our results suggest that C. jejuni does not survivernencystation at 25℃ for 2-3 days in Neff’s Encystment Medium. The same results were observed whenrnMcMillen’s Encystment Medium and refrigeration were used to induce encystation. Our results suggestrnthat internalization of campylobacters by free-living amoebae may present some risk to public health,rnbut that this process may be reversible. Thus, the use of mechanisms to encourage encystation inrnenvironments where elimination of Campylobacter is essential may be a viable option to limit risk andrndecrease Campylobacter survival in its amoebae hosts.