INHIBITION OF ADHESION MOLECULES BY BUDESONIDE ON A HUMAN EPITHELIAL-CELL LINE (LUNG-CARCINOMA)

Inhaled corticosteroids in the treatment of asthma have been shown to produce marked reductions in the number of inflammatory cells (mainly mast cells and eosinophils) and their products at bronchial level (suc h as cytokines). Recently, it has been demonstrated that epithelial ce lls express ICAM-1/CD54 in allergic patients both during natural aller gen exposure and after allergen challenge. We have previously demonstr ated that deflazacort (a systemic steroid) reduces the expression of I CAM-1 on conjunctival epithelial cells. The present study aimed to eva luate the effects exerted by budesonide on adhesion molecule expressio n by a human epithelial cell line (lung carcinoma: DM) and on soluble ICAM-1. Budesonide was added at concentrations corresponding to 10(-8) , 10(-7), and 10(-6) mol/l in cultured epithelial cells, either in the absence of any stimulus or in the presence of interferon-gamma (IFN-g amma) at 500 U/ml. After 24 h of incubation, cytofluorometric analysis was performed for ICAM-1 and CD29/VLA beta 1. The 24-h supernatants o f the same cultures were collected and then evaluated for soluble ICAM -1 (sICAM-1). The results showed that budesonide inhibits ICAM-1 and C D29 basal expression on the cells studied (P<0.05): budesonide was eff ective in a dose-dependent manner. In addition, budesonide reduced sur face ICAM-1 upregulation induced by IFN-gamma at 500 U/ml (P<0.05). Fi nally, cell cultures with budesonide showed decreased levels of solubl e ICAM-1 in basal condition, but not after IFN-gamma stimulation.