The IL-17 neutralizing antibody treatment reverses the inflammatory response mediated by Th17 cells and alveolar enlargement in an experimental model of chronic obstructive pulmonary disease (COPD)

<bold>Background:</bold> Clinical and experimental evidence has been shown the importance of Th17 response in COPD development and progression. <bold>Aims:</bold> To verify the effects of the treatment with a neutralizing antibody for IL-17 in an experimental model of COPD. <bold>Methods:</bold> Mice were exposed to cigarette smoke (CS) for 6 months. Treatment with the neutralizing antibody for IL-17 was carried out since the 5th month of exposure, when there is already the presence of structural changes and an inflammatory process induced by exposure to CS. There are three experimental groups: Control group: animals were placed in a vivarium where they received filtered room air and received treatment with anti-IL17 monoclonal antibody. COPD group: animals that were exposed to CS. Anti IL-17 COPD group: animals that were exposed to CS and received treatment with anti-IL17 monoclonal antibody. We assessed alveolar enlargement by the mean linear intercept (Lm) evaluation and inflammatory profile using the Elisa technique. <bold>Results:</bold> We verified an increase in Lm for the COPD groups (*p== 0,009, compared to the Control and COPD anti IL-17 groups). Also, the expression of interleukins TGF-β, IL-6, IL-10 and IL-17 by ELISA showed increase only in COPD group compared with others (TGF-β *P = 0.003; IL- 6 * P = 0.002; IL -10* P = 0,040; IL- 17 * P = 0.004). <bold>Conclusions:</bold> We showed that treatment with IL-17 neutralizing antibody reversed the inflammatory response mediated by Th17 cells as well as the decrease in alveolar enlargement induced by exposure to CS.