title: Fragmented gelsolins are increased in rheumatoid arthritis-associated interstitial lung disease with usual interstitial pneumonia pattern.
abstract: BACKGROUND
  Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) occurs in 10%-30% of patients with RA, and interstitial lung disease (ILD) is associated with increased mortality in up to 10% of patients with RA. The pathogenesis of RA-ILD is virtually unknown. The aim of this study is to investigate the proteins related to UIP pattern by comparing to OP pattern in RA-ILD using proteome analysis of bronchoalveolar lavage fluid (BALF).
  
  
  METHODS
  Proteomic differences in BALF were compared between the UIP pattern and OP pattern by examining BALF from 5 patients with the UIP pattern and 7 patients with the OP pattern by two-dimensional gel electrophoresis and mass spectrometry.
  
  
  RESULTS
  In individual comparisons of BALF samples, the levels of the protein gelsolin and Ig kappa chain C region were significantly higher in the UIP pattern than in the OP pattern. In contrast, the levels of α-1 antitrypsin, CRP, haptoglobin β, and surfactant protein A (isoform number 5) were all significantly higher in the OP pattern than in the UIP pattern. Gelsolin was cleaved into two fragments, a C-terminal half and N-terminal half, and the levels of both were significantly higher in the UIP pattern than in the OP pattern.
  
  
  CONCLUSIONS
  Fragmented gelsolins may be associated with the pathogenesis of fibrosis in RA-ILD.
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Kozo
authors.initials: K
authors.lastname: Suhara
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical and Dental University, Tokyo, Japan. Electronic address: miyazaki.pilm@tmd.ac.jp.
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Miyazaki
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Okamoto
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ishizuka
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Kimitake
authors.initials: K
authors.lastname: Tsuchiya
authors.affiliation: Department of Respiratory Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Inase
mesh_terms: D000368:Aged; D000595:Amino Acid Sequence; D001172:Arthritis, Rheumatoid / Q000150:complications*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D005260:Female; D018260:Gelsolin / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000175:diagnosis / Q000378:metabolism*; D017563:Lung Diseases, Interstitial / Q000175:diagnosis / Q000209:etiology* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D020543:Proteome; D040901:Proteomics / Q000379:methods
chemical_list: D018260:Gelsolin; D020543:Proteome
keywords: Bronchoalveolar lavage fluid; Gelsolin; Interstitial pneumonia; Proteomics; Rheumatoid arthritis