Figure 4: Mice lung tissues pathohistological changes, total cells and differential cells count in BALF after saline or CEO treatment upon PM2.5 exposure (bar = 50 μm).

Mice lung tissues were obtained on day 3, 7, 14 after administration by PM2.5. Samples were stained using H&E. Histopathological lesions and changes were assessed by histological analyses of six random fields per sample by optical microscope. CEOs significantly reduced cells infiltration and alveolar walls alteration time-dependently (A). CEOs decreased the accumulation of inflammatory cells of BALF. Total cells (B), neutrophils (C), lymphocytes (D) and macrophages (E) of BALF were counted using Giemsa staining. Results are represented as means ± SEM (**P < 0.01, *P < 0.05 versus PM2.5 + saline group).