Levels of intracellular protein and messenger RNA of mucin and lysozyme innormal human nasal and polyp epithelium

Objectives: Mucus hypersecretion is a characteristic feature in chronic sin usitis with nasal polyps, The objective of this study is to examine whether the polyp epithelium itself contributes to a certain extent to the increas ed mucous secretions in chronic sinusitis with nasal polyps, and if it does , to determine which mucin genes are responsible for the increased mucin se cretion. Methods: Three pooled samples of normal nasal epithelial cells fro m each subject were obtained by scrapings from the inferior turbinates of 3 0 healthy adult volunteers and nasal polyps from 6 patients who underwent i ntranasal ethmoidectomy and polypectomy, Isolated epithelial cells were use d for total RNA isolation for reverse transcriptase polymerase chain reacti on and cell lysates for immuno blotting. Results: The intracellular level o f mucin from polyp epithelium was 2.9 times higher than that of normal nasa l epithelium (P <.05). Interestingly, MUC2 and MUC8 messenger RNA (mRNA) le vels were clearly upregulated in polyp epithelium compared with those of no rmal turbinate epithelium. Conclusions: Polyp epithelium can be considered to contribute in part to increased secretion in chronic sinusitis with poly ps, and increased mucous secretion might be related to the increased mRNA l evel of MUC2 or MUG8 or both.