Fig. 1

Presence of AGEs in human lung tissue from IPF patients (IPF) and control group (Control). a1 The antibody used for global AGEs assessment recognized any proteins which contain a glycated region in structure; so the three bands seen (at 60, 50 and 25 kDa) in Western blot analysis correspond with 3 types of AGE-modified proteins. a2 Although Anti-AGEs immunoblot did not show apparent differences between both groups, densitometry analysis showed statistical differences only in the band of 25 kDa and when the values of the three AGEs obtained were considered together. Presence of AGEs was represented as percentage in relation to loading control β-actin (β-act). Statistical analysis was performed using Student’s t-test (*p < 0.05). b1 Parenchyma of lung control showed positive signal (brown color), mainly associated to lumen and endothelium of blood vessels and capillaries. b2 Pneumocytes (arrow) showed a weak and discontinuous staining for anti-AGEs antibody. b3 Ciliated epithelial cells of bronchus showed a blurred pattern of staining in their cytoplasm. b4 Brown immunostaining associated to proteins from the ECM in IPF lungs. b5 Reactive AECs (arrow) and ECM proteins showed immunoreactivity; contrary to fibroblast foci (star), where immunostaining was absent. b6 Apical membrane of ciliated cells from bronchus and endothelium of blood vessels also showed staining. Micrographs recorded at 200X (b1, 4, 5 and 6) and 400X (b2 and 3) magnification