Figure 1
ATRA-attenuated lung inflammation. Mice received i.p. injection of 400 μg/mouse ATRA or vehicle on days -1, 13, 24, and 26, which is 1 day prior to OVA sensitization, while mice were injected with PBS as control. A. The protocol used to evaluate the effects of ATRA on asthma manifestations in vivo. B. BALF from the mice was analyzed 24 h after the final challenge (day 28). Results are shown as the total number of cells in BAL fluid. Total, total cell number; Mac, monocyte/macrophage; Eos, eosinophils; Lym, lymphocytes; PMN, neutrophils. Values expressed as number of cells × 105/ml or 104/ml are means ± SEM (n = 10 in each group; **, p < 0.01). Data are representative of 3 independent experiments. C. Histopathological analyses on lung tissues from three groups at 24 hours after the final challenge (day 28). Mice were sacrificed at 24 hours after the final challenge, lung tissues were stained with H&E, and the inflammatory cells were analyzed by light microscopy (magnification: 200×). An increased number of eosinophils was observed in the vehicle group compared with the control group, while such an increase was obviously attenuated in the ATRA group. Data are representative of 10 mice in each group of 3 independent experiments.