Cathepsin S Contributes to Lung Inflammation in Acute Respiratory Distress Syndrome.

Although the cysteine protease cathepsin S has been implicated in the pathogenesis of several inflammatory lung diseases, its role has not been examined in the context of acute respiratory distress syndrome, a condition that still lacks specific and effective pharmacological treatments. To characterize the status of cathepsin S in acute lung inflammation and examine the role of cathepsin S in disease pathogenesis. Human and mouse model BAL fluid samples were analyzed for the presence and activity of cathepsin S and its endogenous inhibitors.