چکیده (انگلیسی):

Background: Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) occurs in 10%e30% 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 twodimensional
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 a-1
antitrypsin, CRP, haptoglobin b, 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.