Short-term anti-inflammatory activity of orally administered, non-colonizing Escherichia coli
Host-microbiota co-evolution has led to mutually beneficial relationships and constitutes a critical regulatory component of the host's physiology, including the immune system. However, the impact of discrete exposure to bacteria present in food intake is largely unexplored. Here we show that transient gut exposure to Escherichia coli results in a reduced pro-inflammatory cytokine production upon ex vivo stimulation of bone marrow-derived macrophages. Notably, this altered inflammatory phenotype is dependent on a functional microbiota, as no effect was observed in axenic animals. Further investigation into gut microbial composition changes after transient exposure to E. coli in conventional mice shows higher abundance of short-chain fatty acid (SCFAs) producer families, including Oscillospiraceae. In line with this, we observed increased levels of butyrate in mice exposed to E. coli. When subjected to DSS-induced colitis, E. coli-experienced animals show attenuated disease and higher levels of short-chain fatty acids. Overall, our data supports that transient alterations in the gut microbiota may alter host systemic immunity.
Host-microbiota co-evolution has led to mutually beneficial relationships and constitutes a critical regulatory component of the host's physiology, including the immune system. However, the impact of discrete exposure to bacteria present in food intake is largely unexplored. Here we show that transient gut exposure to Escherichia coli results in a reduced pro-inflammatory cytokine production upon ex vivo stimulation of bone marrow-derived macrophages. Notably, this altered inflammatory phenotype is dependent on a functional microbiota, as no effect was observed in axenic animals. Further investigation into gut microbial composition changes after transient exposure to E. coli in conventional mice shows higher abundance of short-chain fatty acid (SCFAs) producer families, including Oscillospiraceae. In line with this, we observed increased levels of butyrate in mice exposed to E. coli. When subjected to DSS-induced colitis, E. coli-experienced animals show attenuated disease and higher levels of short-chain fatty acids. Overall, our data supports that transient alterations in the gut microbiota may alter host systemic immunity.
cic biogune