Figure 6.
HSV-1 replication is modulated by variant MxA protein. (a) Human fibroblasts were infected with a recombinant retrovirus that produces short hairpin RNA to inhibit MxA expression. MxA knockdown or control cells were infected with HSV-1 and virus yields were evaluated by plaque assay at 24 h after infection using three clones of MxA knockdown cells at low passages. Inhibition of MxA expression by siRNA reduced the yields of infections HSV-1 significantly after infection at 1, 0.1 and 0.01 PFU per cell. Each bar represents the mean±s.e. of triplicate titrations (two-tailed Student’s t-test, P=0.003, 0.04 and 0.004, respectively). Data were reproducible with independent clones of MxA knockdown cells and vector controls. (b) Human fibroblasts that expressed variant MxA were infected with HSV-1 and virus yields were evaluated by plaque assay at 24 h after infection. Constitutive expression of variant MxA enhanced HSV-1 yields are as shown; each bar represents the mean±s.e. of triplicate titrations from two independent experiments (two-tailed Student’s t-test, P=0.01).