PT - JOURNAL ARTICLE AU - G.J. Gaschler AU - C.C.J. Zavitz AU - C.M.T. Bauer AU - M.R. Stämpfli TI - Mechanisms of clearance of nontypeable <em>Haemophilus influenzae</em> from cigarette smoke-exposed mouse lungs AID - 10.1183/09031936.00113909 DP - 2010 Nov 01 TA - European Respiratory Journal PG - 1131--1142 VI - 36 IP - 5 4099 - http://erj.ersjournals.com/content/36/5/1131.short 4100 - http://erj.ersjournals.com/content/36/5/1131.full SO - Eur Respir J2010 Nov 01; 36 AB - Inflammation is prevalent in all stages of chronic obstructive pulmonary disease, and, furthermore, individuals undergo periods of exacerbation, during which pulmonary inflammation increases, often a result of bacterial infection. The present study investigates the in vivo consequences of cigarette smoke exposure on bacterial challenge with nontypeable Haemophilus influenzae (NTHi). BALB/c and C57 black 6 (C57BL/6) mice were exposed to cigarette smoke once or twice daily for a total period of 8 weeks. Exacerbated inflammation was observed in cigarette smoke-exposed compared to room-air-exposed mice following challenge with live or heat-inactivated NTHi. Accelerated clearance of live NTHi from cigarette smoke-exposed mice was independent of the establishment of chronic inflammation or direct toxic effects of cigarette smoke components on bacteria. Mechanistically, a cell-free factor in the bronchoalveolar lavage fluid contributed to accelerated clearance following passive transfer to naive mice. Further investigation demonstrated increased titres of immunoglobulin A in the bronchoalveolar lavage fluid, but not the blood, of cigarette smoke-exposed mice, including increased titres of NTHi-specific immunoglobulin A, whereas heavy chain joining element (JH)-/- B-cell-deficient cigarette smoke-exposed mice did not demonstrate decreased bacterial burden following challenge. The present results demonstrate that cigarette smoke exposure results in exacerbated inflammation following challenge with NTHi, as well as increased titres of antibodies that contribute to bacterial clearance.