γ irradiation triggers a wave of IFN-1 response genes in the bone marrow. (A) Expression of IFN-1 response genes in lineage-positive (lineage⁺) and lineage^neg cells in the bone marrow of mice exposed to sublethal, TBI (5 Gy). Samples were analyzed 4 hours, and 1, 3, 7, and 14 days after irradiation. Results are shown as mean ± SEM (n = 4 mice). (B) Effect of neutralizing IFNAR1 on the expression of IFN-1 response genes in lineage⁺ and lineage^neg bone marrow cells after TBI (5 Gy). Samples were analyzed 4 and 72 hours after irradiation in mice treated with control immunoglobulin G1 (IgG1) or neutralizing anti-IFNAR1 antibody as described in “Materials and methods.” Nonirradiated cells (Untr) are shown. Results are shown as mean ± SEM (n = 3-6 mice per condition). (C) Expression of IFN-1 response genes in LSK cells, lineage⁺, and lineage^neg bone marrow cells of Nfat5^fl/fl Vav-Cre or littermate WT mice after TBI (5 Gy). LSK cells were analyzed 6 hours after irradiation, and lineage⁺ and lineage^neg cells at 6 and 72 hours. Nonirradiated cells (Untr) are shown. Results are shown as mean ± SEM (n = 3-6 mice of each genotype). Statistical test: unpaired t test. ∗P < .05, ∗∗P < .01. P values < .1 are also indicated.