[Correlative study of nuclear factor-kappa B activity and cytokine expression in chronic sinusitis]

To investigate the correlation between nuclear factor-kappa B (NF-kappaB) activity and cytokine expression in nasal mucosa of chronic sinusitis.

IL-5, IL-6 and IL-8 levels in nasal mucosa were assayed by the method of ELISA in 52 cases of chronic sinusitis [concomitant with allergic rhinitis (AR group), without allergic rhinitis (NAR group)] and 12 normal subjects. Semi-quantitative RT-PCR and immunohistochemical staining were used to examine P50 and P65 subunits of NF-KB expressions and activation in nasal mucosa. The correlation between activities of NF-KB P50 and P65 subunits and cytokine expression was evaluated.

IL-5, IL-6 and IL-8 levels in both AR and NAR groups were significantly increased (all P < 0.01 for AR group; P < 0.05, 0.05, 0.01, respectively, for NAR group, as compared with normal group), and the levels were much higher in AR group than that in NAR group (P < 0.01, 0.05, 0.01, respectively). The levels of P50 and P65 mRNA in both AR and NAR groups were enhanced (all P < 0.01 for AR group; all P < 0.01 for NAR group, as compared with normal group), and AR group had markedly greater P50 and P65 mRNA levels in comparison with NAR group (both P < 0.05). Immunohistochemical study revealed that nucleus-present rates of P50 and P65 in both AR and NAR groups were significantly higher than those of control group (all P < 0.01), and they were much greater in AR group as compared with NAR group (all P < 0.01). Pearson correlation analysis demonstrated that P50 and P65 nucleus-present rates were closely correlated with IL-6 and IL-8 levels, but not IL-5. The correlation coefficient was 0. 49 for P50 and IL-6, 0. 54 for P50 and IL-8, 0. 61 for P65 and IL-6, and 0.66 for P65 and IL-8 (all P < 0.01).

Activation of P50 and P65 subunits of NF-kappaB might be one of the mechanisms for induction of IL-6 and IL-8 expression in chronic sinusitis. Concomitance of allergic rhinitis with chronic sinusitis further increased activities of NF-kappaB subunits, and further elevated IL-6 and IL-8 expression. IL-5 expression was independent of NF-kappaB pathway in chronic sinusitis.