CXCL8 and chronic rhinosinusitis without nasal polyps: In addition, dexamethasone, but not clarithromycin, statistically significantly down-regulated CXCL8/IL-8 protein levels (Fig. 6a) in culture supernatants from eosinophilic CRSwNP, CXCL10/IP-10 protein levels (Fig. 6b) in culture supernatants from CRSsNP, and mRNA expression levels of CCL20/MIP-3α (Fig. 6f) in sinonasal mucosa from non-eosinophilic CRSwNP.