Fig. 2: IFITM3 limits animal-origin influenza virus infection of human cells.

a Schematic of in vitro infection with animal-origin influenza viruses and representative example flow cytometry dot plots from infected A549 human lung cells. b, e The indicated A549 cells or THP-1 differentiated macrophages were treated +/- IFNβ for 18 h followed by infection with the indicated viruses (MOI 1) for 24 h. Percent infection was determined by flow cytometry and normalized to respective control cells without IFNβ pre-treatment. Error bars represent SEM. Only statistical comparisons between shControl versus shIFITM3 and WT versus IFITM3^−/− are shown, determined by one-way ANOVA followed by Tukey’s multiple comparisons test. Data are representative of 3 independent experiments, each performed in triplicate (n = 9). c, d Western blots of cell lysates at 18 h +/− IFNβ treatment. Note that commercial IFITM3 antibodies weakly detect IFITM2 in addition to IFITM3. The numbers shown above the graph represent exact p values. Source data are provided as a Source Data file. a Created in BioRender. Denz, P. (2024) BioRender.com/z17v580. Gating strategies for flow cytometry are depicted in Supplementary Fig. 2a. A549 cells and Supplementary Fig. 2b. THP-1 cells.