Abstract
Background: CLAD is an irreversible and heterogeneous condition, associating Bronchiolitis Obliterans Syndrome (BOS), and Restrictive Allograft Syndrome (RAS). RAS and early onset of BOS are correlated with a poor prognosis and a significant morbidity in lung transplant recipients. As a part of SysCLAD, a FP-7 funded project aimed to predict CLAD, this study was designed to find biomarkers of CLAD in lung transplant recipients from the French cohort of lung transplant COLT and the Swiss cohort STCS, by using 2 mass spectrometry (MS) techniques.
Methods: BALF and plasma in the 200 first patients of COLT cohort who reached 3 years post-transplantation or developed an early form of CLAD were selected for analysis from systematic visits at months 6 and 12. First, SELDI-TOF MS analysis, a high-throughput method, allowed obtaining individual proteomic profiles using 3 complementary arrays: CM10 (cation array), Q10 (anion array) and IMAC-Cu (copper array). Furthermore, after pooling samples according to patients' phenotype (BOS, RAS, stable), iTRAQ-MALDI-TOF MS and MS/MS analysis, a sensitive and quantitative method, allowed biomarker identification after peptide separation by off-gel fractionation and nano-reversed phase chromatography.
Results: In a pilot study, 45 proteins were differentially expressed in BALF with SELDI-TOF MS analysis. Identification and quantification of these potential biomarkers is currently performed with iTRAQ analysis.
Conclusion: Identification and validation of early biomarkers of CLAD with these two complementary methods may help to understand involved mechanisms and to earlier diagnose CLAD onset at a reversible stage.
- © 2014 ERS
