EOSINOPHIL ADHESION TO CULTURED AIRWAY EPITHELIAL-CELLS FROM GUINEA-PIG LUNGS

We examined the effects of histamine, tumor necrosis factor-alpha (TNF alpha), interferon-gamma (IFN gamma), indomethacin and dexamethasone on the adherence of eosinophils to airway epithelial cells. Epithelial cells were isolated from guinea pig trachea through enzymatic digesti on, and cultured until they showed confluence. Eosinophils were taken by peritoneal lavage from guinea pigs sensitized with horse serum and purified. The adhesion of eosinophils to cultured epithelial cells was examined using Cr-51. The percentage adhesion was obtained by dividin g counts per minute of lysed eosinophils adhered to epithelial cells b y suspended eosinophils. Histamine significantly increased the adhesio n of eosinophils to epithelial cells, while TNF alpha or IFN gamma did not significantly alter the adhesion. Indomethacin significantly inhi bited the adhesion of eosinophils to epithelial cells in both nontreat ed and histamine-induced conditions. Dexamethasone also reduced adhesi on, although it did not reach statistical significance. These findings indicate that histamine induced eosinophil adherence to airway epithe lial cells, suggesting a role of endogenous prostaglandins in adherenc e.