Collagenase in the Lower Respiratory Tract of Patients with Idiopathic Pulmonary Fibrosis

Abstract
To test the hypothesis that idiopathic pulmonary fibrosis (IPF) is mediated through collagenase present in the lower respiratory tract, we used the fiberoptic bronchoscope to obtain fluid from the lower respiratory tract of 24 patients with IPF, 18 controls and nine patients with sarcoidosis. The fluid was analyzed for a variety of enzymes, including collagenase. Fifteen of 21 patients with IPF showed collagenase activity, whereas normal controls and patients with sarcoidosis showed none (PA and TCB fragments.