Polyinosinic-polycytidylic acid induces the expression of GRO-alpha in BEAS-2B cells

Growth-related oncogene protein-alpha (GRO-alpha)/CXCLl is a chemokine that activates neutrophils and plays an important role in inflammatory reactions. Polyinosinic-polycytidylic acid (poly IC) is a synthetic double-stranded RNA (dsRNA), which is a ligand for Toll-like receptor-3. Poly IC mimics viral infection when applied to cells and induces inflammatory and immune responses. In the present study, we found the induction of GRO-alpha in BEAS-2B bronchial epithelial cells treated with poly IC. Pretreatment of cells with 2-aminopurine, an inhibitor for dsRNA-dependent protein kinase (PKR), inhibited the expression of GRO-alpha-induced by poly IC. Overexpression of interferon-regulatory factor-3 (IRF-3) or retinoic-acid inducible gene-I (RIG-I) enhanced the induction of GRO-alpha by poly IC. PKR, IRF-3, and RIG-I may be involved in the poly IC-induced expression of GRO-alpha in BEAS-2B cells. Airway viral infection may elicit GRO-alpha expression in the bronchial epithelium, which may be implicated in inflammatory and immune reactions.