CH25H upregulation is driven by TLR4 Myd88‐independent signaling (Diczfalusy et al, 2009), and indeed, GSEA revealed a strong enrichment of both total TLR‐ and TLR4‐dependent signaling in small airway epithelial cells taken from the lungs of COPD patients compared to smoking controls (Fig EV1B). The gene discussed is TLR4; the disease is chronic obstructive pulmonary disease.