The microbiota regulates neutrophil homeostasis and host resistance to Escherichia coli K1 sepsis in neonatal mice

Here, Hitesh S. Deshmukh et al. report that in neonates, establishment of the intestinal microbiota is associated with neutrophil development. Antibiotic-treated and germ-free mice have reduced numbers of neutrophils and are susceptible to Escherichia coli K1 and Klebsiella pneumoniae sepsis. Reconstitution of the intestinal microbiota promotes interleukin-17 production by innate lymphoid cells and increases plasma granulocyte colony–stimulating factor levels, granulocytosis and host resistance to sepsis.