A Weaning Reaction to Microbiota Is Required for Resistance to Immunopathologies in the Adult (Immunity)

Al Nabhani et al. find that the changes in the intestinal microbiota at weaning induced a vigorous immune response--a `weaning reaction`--that is programmed in time. The weaning reaction is associated with the induction of regulatory T cells, and its perturbation results in increased susceptibility to immunopathologies later in life.