PT - JOURNAL ARTICLE AU - Daniel Popa AU - Gustaf Lejonberg AU - Jonas Erjefält AU - Beata Olejnicka TI - Altered expression of CuZn-SOD and thioredoxin correlate with the histopathological features in small airways of patients with severe COPD AID - 10.1183/13993003.congress-2015.PA3922 DP - 2015 Sep 01 TA - European Respiratory Journal PG - PA3922 VI - 46 IP - suppl 59 4099 - http://erj.ersjournals.com/content/46/suppl_59/PA3922.short 4100 - http://erj.ersjournals.com/content/46/suppl_59/PA3922.full SO - Eur Respir J2015 Sep 01; 46 AB - There is strong evidence that tobacco smoke-induced COPD is associated with an altered redox balance in intracellular/extracellular compartments and an uncontrolled immune-inflammatory response in genetically predisposed individuals. Primary line antioxidants (superoxide dismutases, SODs, catalase, CAT) and the scavenging thioredoxin (TRX) system play pivotal roles in the maintenance of redox homeostasis. Here we have investigated wherever any relationship exists between the density of immunoreactivity to SODs/CAT/TRX and lymphoid aggregates (LAs), macrophages (MQ) or neutrophils infiltration in COPD.Methods: The micro-localizations of MQ, neutrophils, LAs, SODs, CAT, and TRX were investigated by immunocytochemistry using paraffin-embedded lung sections from non-smokers (n=10) and COPD patients (n=10). Histological/immunohistochemical analyses and quantification were performed using the same Region-of-Interest (ROI) in different anatomical compartments: small airway, peripheral pulmonary artery, and alveolar parenchyma.Results: The percentage of CuZn-SOD/TRX immunoreactivity was significantly higher (p<0.05) in well preserved bronchiolar epithelium in severe COPD. Injured organelles resulted in cellular decompartmentalization which was followed by SODs inactivation in damaged ROI. Statistically significant correlation was found between LAs/CuZn-SOD/TRX and MQ/Mn-SOD/EC-SOD within the small airways.In summary, the data suggest that these redox-regulating proteins are highly expressed in severe COPD and there is a relationship between the expression of up-down regulation of antioxidants and the local LAs, MQ, and neutrophils infiltration.