Effect of cytokines on ICAM-1 and ZO-1 expression on human airway epithelial cells


Corresponding author. Tel.: +46 18 4714114; fax: +46 18 551120. godfried.roomans@medcellbiol.uu.se


The presence of adhesion molecules on airway epithelial cells may be important in recruiting leukocytes to the epithelium. The study aimed at investigating the effects of interleukin (IL)-4, IL-8, IL-13 and interferon-γ (IFN-γ) on cell viability and intracellular adhesion molecule (ICAM)-1 and zonula occludens protein (ZO)-1 expression on cultured human basal and columnar airway epithelial cells. Cycloheximide (CHX) induced cell death in both cell lines. The cytokines IL-4, IL-8, IL-13 and IFN-γ had only minor effects on cell proliferation in the columnar 16HBE14o-cells, and inhibited the effects of CHX on cell death. IFN-γ increased ICAM-1 expression in both cell lines. Western blot analysis showed that CHX inhibited both ICAM-1 and ZO-1 expression in the basal cell line. A combination of IL-4 and IFN-γ appeared to break the tight junctions. IL-4 and IL-13 potentiated CHX-induced apoptosis in basal cells but not in columnar cells, possibly due to low levels of the IL-4 receptor. It is concluded that cytokines produced by airway epithelium may have a role in regulating sequestering of leukocytes to the airways during airway inflammation.