Effect Of Intranasal Glucocorticoid On Foxp3~+ T Regulatory Cells In Nasal Polyps

Background nasal polyps is a common nasal disease with high morbidity and post-surgical recurrence rate. It is a chronic inflammatory disorder characterized by intense infiltration of eosinophlils and neutrophils, as well as tissue remodeling consisting of epithelial proliferation, goblet cell hyperplasia, pseudocyst formation, basement membrane thickening, fibrosis and edema. Increasing evidences have demonstrated excessive lymphocytic activation and Th2-bisead cytokine production in nasal polyps, which is associated with immune dysregulation. Foxp3+ CD4+ CD25+ T regulatory cells consist of two main subgroups. One is naturally T regulatory cells which developed in the thymus, another is induced T regulatory cells generated from na?ve T cells in the periphery. T regulatory cells can migrate to site of inflammation and regulate Th2 and Th1 responses through by cell-cell contact and producing regulatory cytokines. Foxp3 is the most specific marker for T regulatory cells and play a role as a master switcher of programming their development and function. Topic corticocorticoids that have been used as a first-line drug for patients with nasal polyps exert beneficial effect on nasal polyps, which was thought to function by exert extensive anti-inflammmation effects. However, the exact mechanism is not fully understood.Objective To evaluate the role of Foxp3+ T regulate cells in nasal polyps and the effect of intranasal glucocorticoid on Foxp3+ T regulatory cells.Methods Expression of Foxp3 was detected by immunohistochemistry and Western blot in 14 cases of chronic rhinosinusitis with nasal polyps and 10 specimens of normal nasal tissue. Foxp3+ CD4+ T regulatory cells was analyzed by double immunofluorescence staining.Results The number of Foxp3+ cells were (125+35)/mm2, (41+15.4)/mm2, and (144+33)/mm2 in control nasal mucosa and nasal polyps before and after treatment with mometasone furoate nasal spray, respectively (P<0.05). While Foxp3+ CD4+ cells were (115+22)/mm2, (37+11)/mm2, and (133+17)/mm2 indicated by double immunofluorescence staining, respectively (P<0.05). The relative levels of Foxp3 in samples of three groups were 0.44+0.15, 0.25+0.11, and 0.67+0.24 by Western blot analysis, respectively (P<0.05).Conclusion Foxp3+ T regulatory cells were decreased in nasal polyps and can be upregulated by intranasal glucocorticoid treatment.