Bronchoalveolar Lavage Fluid (BALF) Collection and Cellular Analysis
The left lung bronchoalveolar lavage was performed with 500 μl ice-cold phosphate-buffered saline (PBS) for three times, and the resultant BALF was centrifuged to separate the cellular components. The cells were re-suspended in 200 μl PBS. Total cell counts were performed using a hemocytometer, differential cell counts were evaluated morphologically by staining cytospin slides of BALF samples with Wright Stain solution (Sigma).