FIG. 6.
Induction of TNF-α secretion in RAW 264.7 cells by HSV-1 mutants with defects in VP16 and UL13 or nuclear translocation of viral DNA. (A) Cells were treated with 100 IU of IFN-γ per ml and infected with 3 × 105 PFU (multiplicity of infection [MOI], 0.6) of in1814 or the rescued virus in1814R per ml. (B) The cells were treated with IFN-γ as above and infected with 3 × 105 PFU (MOI, 0.6) of R7356 or wild-type F strain per ml. (C) Cells preheated to 39.5°C were treated with 100 IU of IFN-γ per ml and infected with 3 × 105 PFU (MOI, 0.6) of tsB7 or wild-type HFEM per ml. The cells were further incubated at 39.5°C. (A to C) After 8 h of infection, supernatants were harvested and analyzed for TNF-α bioactivity. Results are shown as means of duplicate cultures ± standard errors of the means. Similar results were obtained in three independent experiments. ∗, P < 0.05.