A retrospective review on 30 patients on post-lung transplantation with IPF where native lung was collected from 02/2011 to 09/2012. Results of PFTs and mPAP were collected. RNA and protein were isolated for qRT-PCR and western blot from frozen lung explant samples. Controls were 18srRNA and ¦Â-actin. Linear regression and Pearson¡¯s correlation between transcript levels and mPAP were analyzed. p<0.05 was considered significant.
12/30 presented with PH (IPF+PH group); 63 % male; 60 % Caucasian. Linear regression analysis demonstrates no association between PFTs or Collagen I (Col1A1 transcript) levels and mPAP values. mPAP compared to FVC % , TLC % , DLCO % and FEV1 % showed no statistical significance. When mPAP was compared to ADORA2B expression levels, we found a significant correlation (p=0.0373, r2 0.1685) suggesting a link between heightened ADORA2B expression levels and elevated mPAP. [] Western blot corroborated by showing heightened ADORA2B protein levels in IPF+PH.
Results demonstrate a direct positive correlation between ADORA2B and mPAP in patients with IPF; pointing to a role for ADORA2B in the pathophysiology of PH in IPF that could lead to new therapies.