Impact of miRNA inhibitor transfection on virus infection with invivofectamine. Groups of 8 (done twice, total 16) or 9 (lung viral titration) C57BL/6 mice were inoculated intranasally with ma81 H5N2 avian influenza virus (5 MLD50) 24 hours after individual transfection of 30 μg miRNA inhibitors (miR-147-3p, miR-151-5p, miR-155-3p, miR-223-3p) or an miRNA negative inhibitor control (miRNA negative inhibitor control #1; Bioneer Co. Ltd, Daejeon, Korea). Viral growth kinetics in mouse lungs were determined by TCID50 at 1, 3, and 5 dpi (A). Data are expressed as mean × SD titers from 3 lungs per time point. Mean body weight changes (B) and survival rates (C) were monitored in six remaining mice for 14 days. *, P value ≤0.05.