RRC ID 35497
Author Rendueles O, Ferrières L, Frétaud M, Bégaud E, Herbomel P, Levraud JP, Ghigo JM.
Title A new zebrafish model of oro-intestinal pathogen colonization reveals a key role for adhesion in protection by probiotic bacteria.
Journal PLoS Pathog
Abstract The beneficial contribution of commensal bacteria to host health and homeostasis led to the concept that exogenous non-pathogenic bacteria called probiotics could be used to limit disease caused by pathogens. However, despite recent progress using gnotobiotic mammal and invertebrate models, mechanisms underlying protection afforded by commensal and probiotic bacteria against pathogens remain poorly understood. Here we developed a zebrafish model of controlled co-infection in which germ-free zebrafish raised on axenic living protozoa enabled the study of interactions between host and commensal and pathogenic bacteria. We screened enteric fish pathogens and identified Edwardsiella ictaluri as a virulent strain inducing a strong inflammatory response and rapid mortality in zebrafish larvae infected by the natural oro-intestinal route. Using mortality induced by infection as a phenotypic read-out, we pre-colonized zebrafish larvae with 37 potential probiotic bacterial strains and screened for survival upon E. ictaluri infection. We identified 3 robustly protective strains, including Vibrio parahaemolyticus and 2 Escherichia coli strains. We showed that the observed protective effect of E. coli was not correlated with a reduced host inflammatory response, nor with the release of biocidal molecules by protective bacteria, but rather with the presence of specific adhesion factors such as F pili that promote the emergence of probiotic bacteria in zebrafish larvae. Our study therefore provides new insights into the molecular events underlying the probiotic effect and constitutes a potentially high-throughput in vivo approach to the study of the molecular basis of pathogen exclusion in a relevant model of vertebrate oro-intestinal infection.
Volume 8(7)
Pages e1002815
Published 2012-1-1
DOI 10.1371/journal.ppat.1002815
PMID 22911651
PMC PMC3406073
MeSH Animals Bacterial Adhesion* Coinfection Edwardsiella ictaluri / immunology Edwardsiella ictaluri / pathogenicity* Enterobacteriaceae Infections / microbiology Enterobacteriaceae Infections / prevention & control* Escherichia coli / physiology Escherichia coli Proteins / physiology Fimbriae Proteins / physiology Intestinal Mucosa / microbiology* Larva / microbiology Models, Animal Probiotics* Vibrio parahaemolyticus / physiology Zebrafish / microbiology*
IF 6.218
Times Cited 60
Prokaryotes E. coli ?