Evidence of dysregulated cytokine production by sinus lavage and peripheral blood mononuclear cells in patients with treatment-resistant chronic rhinosinusitis.

BACKGROUND Treatment-resistant chronic rhinosinusitis (CRS) imposes a clinical challenge. Its pathogenesis may be associated with dysregulated immune/inflammatory responses in the sinus. OBJECTIVE To evaluate production of types 1 and 2 T cytokines (interferon gamma [IFN-gamma] and interleukin [IL] 5/IL-4, respectively) and regulatory/inflammatory cytokines (IL-10, IL-12, and IL-18) by sinus lavage (SL) cells and peripheral blood mononuclear cells (PBMCs) in patients with treatment-resistant CRS. METHODS Sample SL cells and PBMCs obtained from 19 patients with treatment-resistant CRS were cultured with or without stimuli, and cytokine levels in the supernatant were measured using enzyme-linked immunosorbent assay. Control PBMC samples were obtained from 26 children. RESULTS Chronic otitis media was found in 15 patients. Neutrophils and/or epithelial cells were dominant in SL cells. IFN-gamma, IL-12p40, and IL-10 (>100 pg/mL) were detected in SL cell cultures from 12, 9, and 8 patients, respectively. Production of IL-12p40 and IL-18 by SL cells correlated positively with phytohemagglutinin and IL-12p70 stimuli. In 12 patients, we detected IL-18 (>100 pg/mL) in SL cell cultures without stimuli, whereas PBMCs produced little IL-18, irrespective of stimuli. There was no correlation between cytokine levels produced by SL cells and PBMCs, except for IL-12p40 produced using IL-18. Decreased IFN-gamma production by PBMCs was observed in 6 patients with CRS compared with controls, but 4 of them had elevated IFN-gamma production by SL cells. Production of IL-12p40 by PBMCs was higher in 10 patients with CRS than in controls, and 7 of these patients had lower IL-10 production, resulting in an increased IL-12p40/IL-10 ratio. CONCLUSIONS There is a role for locally produced regulatory cytokines in IFN-gamma production in the sinus in patients with treatment-resistant CRS. However, aberrant cytokine production patterns by PBMCs can be detected at high frequency in these patients, indicating that this can be used as a prognostic marker for patients with CRS.