[Effect of intranasal glucosteroid on the gene expression of interleukin-5 in nasal polyps].

Objective: To investigate the effect of intranasal glucosteroid treatment on the expression of interleukin (IL)-5 gene in nasal polyps.

Methods: Nasal polyps from topical steroid treated patients (n = 20) and untreated patients (n = 20) were investigated with the technique of mRNA in situ hybridization.

Results: The majority of IL-5 mRNA positive cells in nasal polyps were lymphocytes or eosinophils. No statistical significance was found in the densities of IL-5 mRNA positive cells between allergic patients [(12.6 +/- 4.6)/0.25mm2] and nonallergic patients [(14.3 +/- 4.1)/0.25mm2] (t = -0.775, P > 0.05). Compared with the control group [(13.9 +/- 4.2)/0.25mm2], the density of IL-5 mRNA positive cells was decreased in the steroid-treated group [(10. 2 +/- 3.1)/0.25mm2], and the difference reached statistical significance (t = 3.114, P < 0.01).

Conclusions: These findings indicate that topical steroid treatment may suppress the IL-5 gene expression, and steroids may inhibit eosinophil functions.