RT Journal Article SR Electronic T1 Effect of mast cells degranulation blockade on the inflammatory response outcome in the COPD model JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP PA4023 DO 10.1183/13993003.congress-2016.PA4023 VO 48 IS suppl 60 A1 Elena S. Lebedeva A1 Natalija A. Kuzubova A1 Olga N. Titova A1 Ivetta V. Dvorakovskaya A1 Elena A. Surkova YR 2016 UL http://erj.ersjournals.com/content/48/suppl_60/PA4023.abstract AB The contribution of mast cells (MCs) to inflammatory response and lung remodeling in COPD is not well documented.Aim: to assess the effect of MC degranulation blockade on inflammatory response outcome and lung tissue structure in COPD model.Methods: Model of COPD was induced in rats by NO2 (15-19 ppm) exposure: 1,5-2 h/day for 60 days. Sodium cromoglicate (SC, Aventis) was used as MC membrane stabilizer. From 30th to 60th day one group was inhaled with SC before NO2 exposure, control group received 0.9% NaCl. Lung sections were stained with H&E and toluidine blue for MCs. Bronchoalveolar lavage fluid (BALF) cytogram was determined. The levels of mast cell tryptase (MCT) and chymase (MCC), TNFa, surfactant protein B (SP-B) were measured in BALF by ELISA.Results: A lot of MCs, inflammatory infiltration, foci of emphysema were revealed in control lung tissue. The BALF levels of TNFa, SP-B, MCT and MCC increased respectively 10-, 2-, 6- and 3-fold (p<0,05) as compared with intact rats. The neutrophil content increased 7-fold. There were single MCs in lung interstitium of SC-treated rats. SC-treatment decreased levels of TNFa (2,47±0,14 vs. 15,71±0,51 pg/ml in control, p<0,05), SP-B (8,08±1,35 vs. 17,67±2,12 pg/ml, p<0,05), MCT (0,13±0,02 vs. 1,29±0,49 ng/ml, p<0,05), MCC (1,41±0,36 vs. 3,89±0,32 ng/ml, p<0,05) and neutrophils count (6,8±1,2 vs. 20,3±2,1%, p<0,05). Cellular infiltration of the lung tissue and alveolar hyperextension were less marked.Conclusion: The results confirm the involvement of MCs in the development of airway inflammation. Prevention of MC degranulation reduces the activity of the airway inflammation and severity of lung tissue remodeling in rats with COPD model.