FIG 3.
Inhibition of the productivity of H5N1 infection by pretransfection with cIAV DsiRNA swarm in human macrophage and moDCs. Human primary macrophages or moDCs obtained from four different blood donors (A, B, C, and D) were left nontransfected (control, UV IAV, or no siRNA) or separately pretransfected with the indicated siRNA or DsiRNAs (10 nM) for 21 h. Cells were then infected with live or UV-irradiated H5N1 viruses at an MOI of 1. To remove the input virus, macrophages were washed twice with PBS at 1 h p.i. and then maintained in a macrophage medium. MoDC cultures were not washed, and therefore the H5N1 virus titers in supernatant samples at 1 h p.i. represented the input amounts of virus. (A) The infective viral titers produced from macrophages and moDCs were determined by plaque assay in Madin-Darby canine kidney cells. Statistical significance was determined against results from samples of nontransfected H5N1 virus-infected cells (no siRNA; boxed bars). *, P < 0.05; **, P < 0.01. (B) The RNA was isolated from the supernatant samples from macrophages and moDCs, and the viral M1 gene-specific RNA levels were detected by qRT-PCR. The viral RNA expression was calculated relative to the level in UV-irradiated samples with the ΔΔCT method. Statistical significance was determined against results from samples of nontransfected H5N1 virus-infected cells (no siRNA; boxed bars). *, P < 0.05.