TLR9 and chronic rhinosinusitis with nasal polyps: Interestingly, we found that both dexamethasone and clarithromycin were able to increase the mRNA expression of melanoma differentiation-associated gene 5 (MDA-5) (Fig. 9a), toll like receptor (TLR) 2 (Fig. 9b) and TLR3 (Fig. 9c) in sinonasal mucosa from all CRS groups, and mRNA expression of TLR9 (Fig. 9e) in polyp tissues from eosinophilic and non-eosinophilic CRSwNP patients in similar extent.