ART1 and pulmonary fibrosis: The second study corroborated roles for ARTC-1 in inflammatory response – levels of ADP-ribosylated HNP-1 were observed to be elevated within the bronchoalveolar lavage fluid of patients with respiratory inflammatory diseases such as pulmonary fibrosis and asthma, as well as in regular smokers (Paone et al., 2006), implying that MARylation of HNP-1 by ARTC-1 is part of the inflammatory response in the airway.