Gyu-Young Hur1, Gil-Soon Choi1, Seung-Soo Sheen2, Hyun-Young Lee1, Han-Jung Park1, Sung-Jin Choi1, Young-Min Ye1, Hae-Sim Park3. 1. Department of Allergy and Rheumatology, Ajou University School of Medicine, Suwon, South Korea. 2. Pulmonary and Critical Care Medicine, Ajou University School of Medicine, Suwon, South Korea. 3. Department of Allergy and Rheumatology, Ajou University School of Medicine, Suwon, South Korea. Electronic address: hspark@ajou.ac.kr.
Abstract
BACKGROUND: Although methylene diphenyl diisocyanate (MDI) may induce occupational asthma in the workplace, the pathogenic mechanisms are unclear. OBJECTIVES: By using bronchoalveolar lavage fluid, we sought to identify proteins that were differentially expressed between subjects with MDI-induced occupational asthma (MDI-OA) and asymptomatic exposed controls (AECs). METHODS: To find proteins that were differentially expressed between the MDI-OA and AEC groups, 2-dimensional electrophoresis was performed by using bronchoalveolar lavage fluid obtained from subjects after MDI-specific inhalation challenge. The selected protein spots were then identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The clinical relevance of the differentially expressed spots was compared by ELISA using sera from the MDI-OA/eosinophilic bronchitis, AEC, and unexposed healthy control groups. Receiver operating characteristic curves were then plotted, and the sensitivity and specificity were determined. RESULTS: Twenty-three protein spots were identified that distinguished the subjects with MDI-OA from those in the AEC group. Among them, ferritin expression was downregulated whereas transferrin expression was upregulated in subjects with MDI-OA compared with AEC; these results were validated by ELISA using sera from the MDI-OA/EB and AEC groups. To identify subjects with MDI-OA, the optimal serum cutoff levels were 69.84 ng/mL for ferritin and 2.48 microg/mL for transferrin. When these 2 parameters were combined, the sensitivity was 71.43% and the specificity was 85.71%. CONCLUSION: Serum ferritin and transferrin levels are associated with the phenotype of MDI-OA.
BACKGROUND: Although methylene diphenyl diisocyanate (MDI) may induce occupational asthma in the workplace, the pathogenic mechanisms are unclear. OBJECTIVES: By using bronchoalveolar lavage fluid, we sought to identify proteins that were differentially expressed between subjects with MDI-induced occupational asthma (MDI-OA) and asymptomatic exposed controls (AECs). METHODS: To find proteins that were differentially expressed between the MDI-OA and AEC groups, 2-dimensional electrophoresis was performed by using bronchoalveolar lavage fluid obtained from subjects after MDI-specific inhalation challenge. The selected protein spots were then identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The clinical relevance of the differentially expressed spots was compared by ELISA using sera from the MDI-OA/eosinophilic bronchitis, AEC, and unexposed healthy control groups. Receiver operating characteristic curves were then plotted, and the sensitivity and specificity were determined. RESULTS: Twenty-three protein spots were identified that distinguished the subjects with MDI-OA from those in the AEC group. Among them, ferritin expression was downregulated whereas transferrin expression was upregulated in subjects with MDI-OA compared with AEC; these results were validated by ELISA using sera from the MDI-OA/EB and AEC groups. To identify subjects with MDI-OA, the optimal serum cutoff levels were 69.84 ng/mL for ferritin and 2.48 microg/mL for transferrin. When these 2 parameters were combined, the sensitivity was 71.43% and the specificity was 85.71%. CONCLUSION: Serum ferritin and transferrin levels are associated with the phenotype of MDI-OA.
Authors: Berran Yucesoy; Grace E Kissling; Victor J Johnson; Zana L Lummus; Denyse Gautrin; André Cartier; Louis-Philippe Boulet; Joaquin Sastre; Santiago Quirce; Susan M Tarlo; Maria-Jesus Cruz; Xavier Munoz; Michael I Luster; David I Bernstein Journal: J Occup Environ Med Date: 2015-12 Impact factor: 2.162