RT Journal Article SR Electronic T1 Plasma protein signature of idiopathic pulmonary fibrosis (IPF) JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP P548 VO 42 IS Suppl 57 A1 Karl Kossen A1 Xiaoli Qin A1 Sharlene Lim A1 Williamson Bradford A1 Robin Deterding A1 Scott Seiwert YR 2013 UL http://erj.ersjournals.com/content/42/Suppl_57/P548.abstract AB Introduction: Novel protein biomarkers of IPF may provide new insights into disease pathobiology, facilitate diagnosis, and predict disease progression.Objective: Broadly define the plasma protein profile of IPF and identify markers of disease activity.Methods: Plasma was obtained from 30 Caucasian male IPF patients and 20 demographically matched healthy volunteers. IPF samples were selected to include 15 patients that experienced significant decline in forced vital capacity over 48 weeks (median -15.2%) and 15 with a lower level of decline (median -2.7%). 1129 proteins were quantified using an aptamer-based proteomic platform (SomaLogic). Data were median normalized and differentially expressed proteins identified by Kolmogorov-Smirnov test with corrections for multiple comparisons (FDR <0.01 and fold change ≥1.2x). Pathway analysis was performed using MetaCore (Thomson Reuters).Results: The plasma protein signature of IPF is markedly different from that of healthy volunteers. Consistent with previous reports, markers including MMP-7, periostin, and CCL18 are significantly increased in IPF plasma. In addition, several differentially expressed proteins correspond to mRNAs known to be differentially expressed in IPF lung tissue. Among several newly identified biomarkers are the secreted growth factors pleiotrophin and midkine. The plasma protein profile of IPF shows activation of pathways involved in immune response, cytokine signaling, cell adhesion, and apoptosis.Conclusions: Our results provide a broad, unbiased characterization of the plasma protein profile of IPF and define significant alterations relative to healthy individuals. Further analysis to identify markers of disease progression is underway.