Bleomycin-induced pulmonary fibrosis is found to be significantly attenuated in C/EBPζ-deficient (C/EBPζ−/−) mice; however, the number and polarization of alveolar and interstitial macrophages does not differ significantly after bleomycin treatment, indicating that C/EBPζ expression in lung macrophages has no effect on pulmonary fibrosis [45]. The gene discussed is CEBPZ; the disease is pulmonary fibrosis.