[Expression and distribution of Fas and Fas-L in the nasal polyps].

OBJECTIVES

To confirm the expression and distribution of Fas and Fas-L in the nasal polyps and to illustrate the role of the Fas/Fas-L system in the pathogenesis of human nasal polyps.

METHODS

Investigating the transcripts of the Fas/Fas-L gene in 30 human nasal polyp tissues and 30 nasal turbinate mucosa specimens using reverse transcription-polymerase chain reaction. Localization of Fas/Fas-L was performed with immunohistochemistry.

RESULTS

The transcripts of the Fas/Fas-L gene were detected at similar levels in both polyps and nasal mucosa. There was a significant overexpression of Fas-L protein on nasal polyps (epithelium: 25 +/- 21, glands: 19 +/- 14) compared to nasal mucosa (epithelium: 14 +/- 13, glands: 12 +/- 10), (t = 1.66, P < 0.01), while Fas was overexpressed on nasal mucosa (epithelium: 17 +/- 11, glands: 17 +/- 13) compared to nasal polyps (epithelium: 13 +/- 10, glands: 11 +/- 9), (t = 1.98, P < 0.01). Fas-L positive cells were localized on the epithelial layers of cystically dilated glands and the down-growing epithelium of nasal polyps. Fas positive cells were localized on the cilia of the epithelial of nasal mucosa and mainly on the infiltrative cells.

CONCLUSION

Fas/Fas-L may play an important role on the pathogenesis of human nasal polyps, including cystic degeneration of submucosal glands, apoptosis and conferring of immune privilege to nasal polyp formation.