Figure 3.

Interferon‐γ null mice have altered immune cell populations and resolution kinetic parameters in Influenza‐induced ALI. Ifng ^−/− or WT mice were challenged with intratracheal Influenza A/PR/8/34 H1N1 (PR8) administered at day 0. Mice were examined at day 15 post PR8‐induced for injury parameters or immunophenotyping in lung digests. (a) Body weight relative to baseline determined after injury (n = 26 for Ifng ^−/− mice; n = 31 for WT mice, combining three independent experiments). (b) BAL cell counts and (c) BAL total protein determined on day 15 after PR8‐induced injury between Ifng ^−/− or WT mice (n = 12–14 per genotype, combined from 2 or more independent experiments). (d) Total lung cell count obtained from lung digests obtained at day 15 post PR8 treatment exhibit similar cellularity (n = 12–14 per genotype, combined data of 2 independent experiments). (e) Changes in lung macrophage subpopulations and neutrophils as total numbers in single‐cell suspensions determined by flow cytometry with gating adapted from Misharin et al. (2013). (f) Changes in CD3⁺, CD4⁺, CD8⁺, Foxp3⁺, γδ⁺, CD19⁺, NK T lymphocyte subsets, or NK cells as total numbers in single‐cell suspensions determined using a previously published lymphocyte flow cytometric panel and gating approach (Mock et al., 2019). Data are expressed as the mean ± SEM. p values determined by either Mann–Whitney rank sum test or one‐way ANOVA with the Holm–Sidak, multiple comparison tests. *p < .05, **p < .01, ****p < .0001