Dynamic interactions within the host-associated microbiota cause tumor formation in the basal metazoan Hydra
Menée sur le métazoaire Hydra oligactis et à l'aide d'une souche bactérienne (Turneriella parva), cette étude met en évidence le rôle des interactions entre les bactéries pathogènes et le microbiote de l'hôte dans la tumorigenèse
Author summary Here we follow up on our initial observation of tumor formation in the basal metazoan Hydra and demonstrate that tumor development in one of the evolutionary oldest animals is caused by a dynamic interplay between an environmental spirochete, the host-associated resident microbiota, and the tissue homeostasis within the animal. Unexpectedly, the pathogenicity of the environmental bacterium Turneriella is context-dependent: the virulence of this pathogen requires the presence of a member of Hydra’s beneficial microbiome—the Pseudomonas bacterium. Dynamic interactions between two microbiota members have profound effects onto the host tissue homeostasis and fitness. Our data provide direct evidence for the important role of the resident microbiome in maintaining tissue homeostasis and pathogen defense, a fundamental process that is likely to take place in every tissue of every animal species. In summary, our study uncovers an evolutionary conserved role of the resident microbiome in guarding host’s tissue homeostasis.
PLOS Pathogens 2020