FIG 1.

High-content microRNA screen against three flaviviruses, DENV, WNV, and JEV. (A) HeLa cells were transfected with miRNAs from the Dharmacon/Thermo Scientific v16.0 library and infected with DENV, WNV, or JEV (MOI = 0.5 FFU/cell) at 48 h posttransfection in 96-well plates in triplicate. At 24 h (WNV and JEV) or 48 h (DENV) posttransfection, cells were fixed and immunostained with antiflavivirus envelope antibody/AF488-anti-mouse IgG and DAPI to visualize nuclei. Total AF488 and DAPI signals were quantitated and normalized to those for miRNA control-transfected wells. miRNAs causing >20% toxicity were eliminated from the analysis. Volcano plots indicate the performance of miRNAs against DENV, WNV, and JEV infections. Active miRNAs (>60% inhibition; P value of <0.05) are denoted in blue. Highly represented miRNA families with activity against all three flaviviruses are shown at the right. (B) HeLa cells were reverse transfected with the indicated miRNAs and infected with DENV, WNV, and JEV at an MOI of 0.5 FFU/cell at 48 h posttransfection. Supernatants were collected at 48 h, and infectious virus was quantitated by a focus-forming assay.