Distribution change of mast cells in human nasal polyps

Recent studies have shown that mast cells are involved in pathophysiologic processes of chronic inflammation. However, little is known about the distribution of mast cells in nasal polyps, which is a chronic inflammatory disease of the upper airways. Biopsy specimens from patients with nasal polyps (n = 20) and control patients without nasal polyps (n = 8) were included in this study. The distribution of mast cells in nasal polyps was determined by immunohistochemistry. Meanwhile, we detected the expression of chemokines (CCL5, CCL11, CX3CL1, IL-8, IL-6) in the epithelial cells of normal nasal mucosa and nasal polyps. In addition, the expression of these chemokines was investigated by western bolting in airway epithelial cells line (A549 cells) under inflammatory condition. Mast cells migrated toward intraepithelium in nasal polyps and the expression of chemokines (CCL5, CCL11, CX3CL1, IL-8) was up-regulated in the epithelial cells of nasal polyps compared with normal nasal mucosa. The expression of chemokines was also up-regulated in A549 cells after Lipopolysaccharide (LPS)-treatment for 3 hr and 6 hr. Our findings showed that mast cells migrate toward intraepithelium in nasal polyps and the overexpression of chemokines (CCL5, CCL11, CX3CL1, IL-8) suggested that they might be responsible for mast cells migration. It implies that mast cell play potential roles in the development of nasal polyps.