Disruption of the Peyer’s patches is dependent on type I IFNs. (A) Mice were treated as in Figure 1, and organs were examined 48 hours after the last poly(I:C) injection. Cell numbers in Peyer’s patches and PLNs of wild-type and IFNaR^−/− mice are shown. Each data point represents 1 individual mouse, and the mean of n = 5 mice per group is depicted as a bar. (B) Mice were treated with recombinant IFN-α, and organs were examined 24 hours after the last injection. Cell numbers in Peyer’s patches are shown. Each data point represents 1 individual mouse, and the mean of n = 6 mice per group is depicted as a bar. Data are representative of 2 independent experiments.