Cyclooxygenase 2 and lipoxin A₄ in nasal polyps in cystic fibrosis.

BACKGROUND

The etiology of nasal polyps (NPs) and sinusitis in cystic fibrosis (CF) patients is still unknown. This study investigates the presence of cyclooxygenase 2 (COX-2) and lipoxin A(4) (LXA(4)) in epithelial cultures derived from NPs and turbinates in patients with CF and without CF.

METHODS

NPs and turbinates were evaluated from eight CF patients with obstructing NPs undergoing sinus surgery. NPs and tissue from the hypertrophic inferior turbinate from 14 patients without history of CF undergoing sinus surgery served as control specimens. After tissue culturing, the presence of COX-2 protein and LXA(4) (ELISA) was detected in CF polyps and turbinates and compared with that of the control group.

RESULTS

COX-2 and LXA(4) were detectable in tissue specimens of all CF patients and control patients. COX-2 was highest in CF polyps, but the difference was not significant compared with CF turbinates or polyps and turbinates of patients not suffering from CF. LXA(4), however, was significantly higher in CF NPs compared with CF turbinate tissue. Compared with NPs of patients not having CF disease, CF polyps showed markedly higher concentrations of LXA(4).

CONCLUSION

LXA(4) is significantly elevated in CF NPs, whereas COX-2 is only slightly increased. The present data support the concept that LXA(4) plays an important role in CF nasal polyposis. Chronic infection in nasal polyposis and, because of inflammation, induced COX-2 in CF NPs may be related to increased LXA(4). The suspected interaction of COX-2 and LXA(4) needs further investigation.