In mice, lung epithelial-specific inactivation of C/EBPβ resulted in impaired CS-induced neutrophil recruitment to the lung and compromised induction of neutrophil chemoattractants, but its contribution to emphysema is unclear, in particular because the mRNA levels of C/EBPβ were down-regulated in the airway epithelium of smokers [56], which is difficult to align with the previous findings from the same group that the C/EBP binding activities were increased in the lung tissue from healthy smokers but not from COPD and chronic bronchitis patients [53]. Here, CEBPA is linked to chronic bronchitis.