title: Chitotriosidase in the Pathogenesis of Inflammation, Interstitial Lung Diseases and COPD.
abstract: As a member of 18 glycosyl hydrolase (GH) family, chitotriosidase (Chitinase 1, CHIT1) is a true chitinase mainly expressed in the differentiated and polarized macrophages. CHIT1 is an innate immune mediator that digests the cell walls of chitin-containing eukaryotic pathogens, such as fungi. However, CHIT1 is dysregulated in granulomatous and fibrotic interstitial lung diseases characterized by inflammation and tissue remodeling. These include tuberclosis, sarcoidosis, idiopathic pulmonary fibrosis, scleroderma-associated interstitial lung diseases (SSc-ILD), and chronic obstructive lung diseases (COPD). CHIT1 serum concentration correlates with the progression or the severity of these diseases, suggesting a potential use of CHIT1 as a biomarker or a therapeutic target. Recent studies with genetically modified mice demonstrate that CHIT1 enhances TGF-β1 receptor expression and signaling, suggesting a role in initiating or amplifying the response to organ injury and repair. This additional CHIT1 activity is independent of its enzymatic activity. These studies suggest that CHIT1 serves a bridging function; it is both an innate immune mediator and a regulator of tissue remodeling. This review will focus on recent data linking CHIT1 to the pathogenesis of inflammation, interstitial lung disease, and COPD.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, New York-Presbyterian Hospital-Weill Cornell Medical Center, Weill Cornell Medical College, New York, NY, USA.
authors.forename: Soo Jung
authors.initials: SJ
authors.lastname: Cho
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, New York University School of Medicine, New York, NY, USA. ; New York University, School of Medicine, Department of Environmental Medicine, Tuxedo Park, NY, USA. ; Bureau of Health Services and Office of Medical Affairs Fire Department of New York, Brooklyn, NY, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Weiden
authors.affiliation: Molecular Microbiology and Immunology, Brown University,Warren Alpert School of Medicine Box G-L, Providence, RI, USA.
authors.forename: Chun Geun
authors.initials: CG
authors.lastname: Lee
keywords: Chitotriosidase; TGF-beta; idiopathic pulmonary fibrosis; inflammation; sarcoidosis; scleroderma