Figure 1.

(A) Acute exposure to IQOS aerosols or combustible cigarettes (CS) induces lung epithelial-cell damage. At the end of the exposures, mice were euthanized, bronchoalveolar lavage (BAL) harvested, and the levels of albumin in the BAL were quantified by ELISA as described in Materials and Methods. (B–C) Acute exposure to IQOS aerosols or smoke from CS modulates airway immune-cell infiltration. Total number of leukocytes, CD11b⁺Ly6G⁺ neutrophils, and CD11b⁺Ly6G^-CD68⁺ macrophages (B), and numbers of CD4⁺ T cells, CD8⁺ T cells, and CD19⁺ B cells and CD4⁺IL17A⁺ and CD4⁺RORγt⁺ inflammatory T cells (C) in the lungs of mice exposed to air, IQOS aerosols, or CS were determined by flow cytometry using specific markers and following a gating strategy as described previously⁹ and shown in Supplementary Figure 2. Data are mean ± SE. *p ≤ .05, **p ≤ 0.01, ***p ≤ .005, ****p ≤ .0001, two-way ANOVA with Tukey’s post-test comparisons by GraphPad Prism 8 software (GraphPad, La Jolla, CA). In each experiment, n = 10 mice were used.