CEBPB and pulmonary fibrosis: These Ceacam1+Msr1+Ly6C−F4/80−Mac1+ monocytes, named SatM (segregated-nucleus-containing atypical monocytes), are regulated by CCAAT/enhancer binding protein β (C/EBPβ), and C/EBPβ knockout mice do not develop lung fibrosis following bleomycin treatment.