Impact of ectopic expression of miRNAs on HCMV replication.

<p>(A) HCMV miRNA levels were quantitated by stem-loop RT-PCR in HEL cells 48 h after transduction with empty vector lentivirus (control) or with lentiviruses engineered to express miR-UL22A, miR-UL70, miR-US33, or 48 hpi of HELs with HCMV strain Towne (MOI = 5). Results represent fold-differences for each miRNA relative to control. (B) Levels of IE1, IE2, UL44, or gB were determined by western blotting. Actin serves as a loading control. Control lentivirus (−) or lentiviruses expressing according miRNAs (+) are indicated. (C) HELs were infected with HCMV strain Towne at an MOI of 0.01 48 h after transduction with control lentivirus or lentivirus expressing miR-US33. At the times indicated post infection HCMV genome copy numbers were determined by qPCR. (D) HELs were infected with HCMV strain Towne at an MOI of 0.01 48 h after transduction with control lentivirus or lentivirus expressing miR-US33 Infectious virus titers in supernatants at 96 and 144 hpi were determined. Inhibition efficiencies are % changes in virus titers in medium from HCMV-infected miR-US33-transduced cells vs. control-transduced cells. **P<0.01, *P<0.05.