Mediators and cytokines in allergic and viral-triggered rhinitis

Intermittent allergic rhinitis and common cold constitute frequent conditions and show similar clinical symptoms. The purpose of this study was to investigate the pattern of cytokines in the nasal fluid of patients with acute symptoms caused by allergic and viral rhinitis. Nasal secretions were analyzed by immunosorbent assay techniques using a cytokine panel assay and routine ELISA. Allergic patients had significantly higher levels of eosinophil cationic protein (ECP), interleukin (IL)-5, and tryptase. Significantly elevated concentrations of proinflammatory cytokines (IL-1b, IL-6, IL-7, IL-17, interferon [IFN] γ, and tumor necrosis factor [TNF]-α) as well as chemokines for cellular infiltration (IL-8, monocyte chemoattractant protein 1, and macrophage inflammatory protein 1β), factors for cellular proliferation (granulocyte colony-stimulating factor [G-CSF] and granulocyte macrophage colony-stimulating factor [GM-CSF]), and elastase were found in viral rhinitis. IL-10 was only detectable in viral rhinitis. IL-4 was significantly higher in patients with viral rhinitis than allergic rhinitis, and IL-5 was significantly elevated in viral rhinitis compared with controls. In viral-triggered rhinitis, we detected a predominantly Th1-type cytokine pattern with potent proinflammatory mediators. Factors reflecting a neutrophil and eosinophil immune response, due to IL-5, IL-8, GM-CSF, ECP, and elastase were shown. Nasal secretions of patients with allergic rhinitis showed highest concentrations of tryptase, IL-5, and ECP, reflecting a mast cell and eosinophil immune response. Nasal secretion levels of IL-4 did not show highest levels in allergic rhinitis but did in viral rhinitis. IL-4 also may play a role in limiting inflammatory processes by inhibiting the production of inflammatory cytokines.