Progesterone (P4) treatment promotes barrier integrity, cellular proliferation, and induction of amphiregulin (AREG) in the lungs of IAV-infected female mice.
Figures are generally photos, graphs and static images that would be represented in traditional pdf publications.
Adult female mice were ovariectomized, treated with placebo (-P4) or exogenous P4 (+P4), and inoculated with lethal IAV or mock-infected. At peak disease (7dpi), bronchoalveolar lavage (BAL) fluid or whole lungs were harvested or fixed for histology. Total protein content in the BAL was measured by BCA assay (A). Cellular proliferation was assessed at 7 dpi using the marker Ki67 in paraffin-embedded lung tissue sections; sections were counterstained with hematoxylin; and arrows indicate examples of Ki67+ cells (C). The percentages of Ki67+ cells were analyzed and quantified using ImageJ (B and C; 10X magnification). Areg mRNA expression was quantified and normalized to Gapdh and to mock-infected controls (D). The percentages of AREG+ cells (red) in bronchioles and alveolar airspace were analyzed using immunofluorescence and quantified using ImageJ (E; n = 20 fields/treatment). Representative images of bronchioles (10X magnification) and focused areas (40X magnification) with epithelial cells (β-tubulin+ cells, in green) are shown (F). Bars represent means ±SEM from two or three independent experiments. Significant differences are represented by an asterisk (*) (mock: n = 6; IAV: n = 10–12).