TmT1 serine protease from cowshed dust extracts generates biologically active C5a in murine bronchoalveolar lavages

Introduction: Intranasal application of cowshed dust extract (CDE) during sensitisation in a murine model of OVA-allergy leads to significant alleviation of the clinical parameters of allergic asthma. However, neither the underlying immunological mechanisms nor the protective substances have been described yet. Methods: CDE was fractionated by size exclusion chromatography and anion exchange chromatography. Fractions with proteolytic activity were characterized by zymography and proteolytic bands were identified by mass spectrometric analysis. Murine BALFs were incubated with either CDE or with purified protease…