The Effect of Alternaria Alternata Proteases on Mouse Airway Epithelial Cell Function and Inflammatory Cell Recruitment

Abstract

A murine model has been utilized to investigate the acute effect of Alternaria alternata proteases on airway epithelial cell function and inflammatory cell recruitment. Alternaria exposure and sensitization is associated with the development of asthma in humans and mice, and proteases may be an important component contributing to this effect. Balb/c mice were exposed to Alternaria culture filtrate or filtrate that had been treated either with AEBSF, a serine protease inhibitor, or by heat inactivation to inactivate proteases. Cytokine production was assessed by enzyme-linked immunosorbent assay (ELISA) and real-time quantitative polymerase chain reaction (RT-qPCR); inflammatory cell recruitment was analyzed by lung histology and BALF cytology; and mucin and collagen production was evaluated by lung histology and RT-qPCR. Alternaria serine proteases have been found to play an important role in the induction of inflammatory cytokines and associated inflammatory cell recruitment, while other proteases and allergenic proteins contribute to cytokine production and inflammation less significantly. Mild goblet cell metaplasia was observed in all mice exposed to Alternaria filtrate. There was no observed increase in collagen deposition.