873. Chronic Obstructive Pulmonary Diseases-Like Pathologic Changes by Chronic Infection of Pseudomonas aeruginosa in CCSP-Deficient Mice
Session: Poster Abstract Session: Bacterial Infections: Pathogenesis and Immunity
Friday, October 9, 2015
Room: Poster Hall
Background: Pseudomonas aeruginosa is detected frequently in cases of chronic respiratory disease such as bronchiectasis and cystic fibrosis, and results in chronic refractory infection. However, it remains unclear how chronic respiratory infection affect respiratory disease. The Clala cell secretory protein (CCSP) is a protein abundantly expressed in the airways of mammals and considered to be a regulator of lung inflammation. In this study, we tried to establish chronic P. aeruginosa infection model in mice and investigated whether or not chronic infection affect the lung of CCSP-deficient mice.

Methods: P. aeruginosa PAO1 strain and CCSP-deficient mice background 129 was used in this study. A tube of 1cm in length soaked in the fluid containing P. aeruginosa (PAO01) at the 1x106 cfu/ml for one week was inserted into trachea. One week later, 5x106 cfu/head of P. aeruginosa was administered into trachea. Five week later, mice were sacrificed. Bacterial growths in lungs and bronchiolo-alveolar lavage (BAL) fluid were collected. Cell count in BAL fluids and histology of the lungs were tested. Also physiology of the lungs (pressure-volume curve) was investigated.

Results: P. aeruginosa was continuously detected in BAL fluids during 5 weeks. Inflammatory cells infiltrates around bronchioles, but not alveoli, were observed. Neutrophils in BAL fluids from the CCSP-deficient mice were increased in comparison with that from wild-type mice. Histologic study demonstrated that chronic inflammation developed more serious obstruction of bronchioles and alveolar enlargement in the CCSP-deficient mice without fibrosis. Lung physiology study demonstrated that lung compliance was elevated in the CCSP-deficient mice.

Conclusion: These results indicated that chronic respiratory infection of P. aeruginosa resulted in chronic obstructive pulmonary disease (COPD)-like pathological condition in CCSP-deficient mice.

Masaki Fujita, MD, PhD, Takemasa Matsumoto, MD, PhD, Ryosuke Hirano, MD, Junji Uchino, MD, PhD and Kentaro Watanabe, MD, PhD, Respiratory Medicine, Fukuoka University Hospital, Fukuoka, Japan

Disclosures:

M. Fujita, None

T. Matsumoto, None

R. Hirano, None

J. Uchino, None

K. Watanabe, None

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