Lung inflammation. A, B. Total free lung cells in bronchoalveolar lavage fluid, measured by flow cytometry. C, D. Total neutrophils in bronchoalveolar lavage fluid. Data are mean ± SEM. *p value vs. sham < 0.05; #p value vs. 3R4F < 0.05. E. Inflammatory mediators in cell-free supernatants from bronchoalveolar lavage fluid in rat studies. Changes in inflammatory mediator levels relative to the levels in the sham group are color-coded. F. Inflammatory mediators in cell-free supernatants from bronchoalveolar lavage fluid in mouse studies. G. Changes in inflammatory mediator levels in in vitro assessment of organotypic small airway cultures. *p value < 0.05. See Fig. 3 legend for details on the study and group labeling. SEM, standard error of the mean; THS, Tobacco Heating System; CHTP, Carbon Heated Tobacco Product.