Classification of idiopathic interstitial pneumonias using anti–myxovirus resistance-protein 1 autoantibody

• DOI: 10.1038/srep43201
• Publication Date: 2017-02-23T10:32:31Z
• Authors: Yoshimasa Hamano; Hiroshi Kida; Shoichi Ihara; Akihiro Murakami; Masahiro Yanagawa; Ken Ueda; Osamu Honda; Lokesh P. Tripathi; Toru Arai; Masaki Hirose; Toshimitsu Hamasaki; Yukihiro Yano; Tetsuya Kimura; Yasuhiro Kato; Hyota Takamatsu; Tomoyuki Otsuka; Toshiyuki Minami; Haruhiko Hirata; Koji Inoue; Izumi Nagatomo; Yoshito Takeda; Masahide Mori; Hiroyoshi Nishikawa; Kenji Mizuguchi; Takashi Kijima; Masanori Kitaichi; Noriyuki Tomiyama; Yoshikazu Inoue; Atsushi Kumanogoh
• Keywords: Adult; Male; Myxovirus Resistance Proteins; Middle Aged; Article; 3. Good health; Amino Acyl-tRNA Synthetases; 03 medical and health sciences; 0302 clinical medicine; Humans; Female; Idiopathic Interstitial Pneumonias; Biomarkers; Aged; Autoantibodies

AbstractChronic fibrosing idiopathic interstitial pneumonia (IIP) can be divided into two main types: idiopathic pulmonary fibrosis (IPF), a steroid-resistant and progressive disease with a median survival of 2–3 years, and idiopathic non-specific interstitial pneumonia (INSIP), a steroid-sensitive and non-progressive autoimmune disease. Although the clinical courses of these two diseases differ, they may be difficult to distinguish at diagnosis. We performed a comprehensive analysis of serum autoantibodies from patients definitively diagnosed with IPF, INSIP, autoimmune pulmonary alveolar proteinosis, and sarcoidosis. We identified disease-specific autoantibodies and enriched KEGG pathways unique to each disease, and demonstrated that IPF and INSIP are serologically distinct. Furthermore, we discovered a new INSIP-specific autoantibody, anti–myxovirus resistance-1 (MX1) autoantibody. Patients positive for anti-MX1 autoantibody constituted 17.5% of all cases of chronic fibrosing IIPs. Notably, patients rarely simultaneously carried the anti-MX1 autoantibody and the anti–aminoacyl-transfer RNA synthetase autoantibody, which is common in chronic fibrosing IIPs. Because MX1 is one of the most important interferon-inducible anti-viral genes, we have not only identified a new diagnostic autoantibody of INSIP but also obtained new insight into the pathology of INSIP, which may be associated with viral infection and autoimmunity.