IRF9 and graft versus host disease: Using this approach, we observed that microglia from GVHD animals had enriched regulon activity for Stat (i.e., Stat1, Stat2, Stat3, Stat4, and Stat6), NF-κB (i.e., Nfkb1, Rela, and Rel), and IFN regulatory factor (i.e., Irf1, Irf2, Irf3, Irf7, and Irf9) family transcription factors (Figure 2G), which are all constituents of regulatory networks that mediate inflammation (37).