Hypomethylation around type 1 IFN-regulated genesIn naïve SLE B cells, chromatin accessibility is enhanced around NFkB, AP-1, BATF, IRF4, and PRDM1 binding sites, promoting B cell activation and differentiation.DN2 cells have increased chromatin accessibility at T-bet, EGR, and AP-1 motifs.ABCs have increased chromatin accessibility at T-bet, IRF, and AP-1 motifs.HDACs generally promote B cell class switching, PC differentiation, and autoimmunity in mouse lupus models. Here, IRF4 is linked to systemic lupus erythematosus.