The location of these specific inflammatory features coincides with the peribronchial location of Hhip-expressing murine fibroblasts as shown by Tsukui and colleagues (46), and the observation of IL-18 induction in human adult lung fibroblasts upon silencing of HHIP suggests a plausible role of the mesenchymal HHIP in the inflammatory pathophysiology of COPD. The gene discussed is IL18; the disease is chronic obstructive pulmonary disease.