CTSG and non-small cell lung carcinoma: Our aim was to elucidate whether CatG and NE, a protease secreted by activated neutrophils into the extracellular space [14], are capable of binding in a proteolytic manner to the surface of the human alveolar basal epithelial cell line (A549) or human epithelial-like, non-small cell lung carcinoma cell line derived from the lymph node (H1299).