Regulation of GROα production in human bronchial epithelial cells

Background: Neutrophilic airway inflammation has been suggested to play a crucial role in chronic inflammatory airway diseases such as asthma and COPD, and airway epithelial cells are involved in their regulation. growth-related gene α (GROα) has been reported to be expressed in the sputum of COPD patients. However, the role and clinical significance of GROα are poorly understood. Aims: We investigated the regulation of GROα production in human bronchial epithelial cells in vitro . Methods: We stimulated human bronchial epithelial cell line BEAS-2B with exogenous agents such as LPS and house dust mite (HDM) derp1 as well as TNFα. GROα production and expression were determined by ELISA and qRT-PCR. Furthermore, we evaluated the inhibitory effect of therapeutic agents associated with its regulation. Results: LPS and TNFα showed significant concentration-dependent effects on GROα expression and production in human BEAS-2B cells, and fluticasone (FP) suppressed this production. HDM derp1 also showed a significant concentration-dependent effect on GROα production, but the effect was less potent compared with those by LPS and TNFα. Conclusions: LPS and TNFα showed a potent stimulatory effect on GROα expression and production in human BEAS-2B cells. FP suppressed this production, implying that GROα is involved in chronic inflammatory airway diseases where FP show therapeutic effects.