Fig. 2

Differential cell counts in bronchoalveolar lavage fluid (BALF). The distribution of cell counts in BAL fluid is depicted in (A), the change in total cell counts is presented in (B), and the alterations in COPD-C and COPD-A model according to PM treatment for each cell type is illustrated in (C). COPD, chronic obstructive pulmonary disease; PM, particulate matter. *: p < 0.05, **: p < 0.01, ***: p < 0.001, ****: p < 0.0001, and ns: non-significant