FIG 10.

Neutralization of TNF-α and IFN-γ promotes EBV lytic replication induced by BZLF1Δ207-210. (A to C) P3HR-1 cells were transduced with lentivirus-based BZLF1 or BZLF1Δ207-210 or control vector. After 6 h, BZLF1- or BZLF1Δ207-210-transduced P3HR-1 cells were incubated with anti-TNF-α- or anti-IFN-γ-neutralizing antibodies or isotype IgG in the different combinations and at the different time points as indicated. (A) After incubation for 48 h, expression of viral genes was detected by Western blot analyses as indicated. (B and C) Then, the intracellular DNA genome (B) and the extracellular virion particles (C) were collected and levels were determined as described in Materials and Methods. (D to F) BZLF1-KO EBV BAC-harboring BJAB cells were infected with GFP-tagged wild-type BZLF1- or BZLF1Δ207-210-expressing lentiviruses (MOI = 10). At 6 h after lentiviral infection, anti-TNF-α- or anti-IFN-γ-neutralizing antibodies or isotype IgG was added as indicated. (D) Levels of expression of viral genes were detected by Western blot analyses after incubation with antibodies for 48 h. (E) After incubation for 3 days, the cells were collected and intracellular viral genomic DNAs were extracted and analyzed by real-time PCR for intracellular viral DNA replication. (F) After incubation for 5 days, the supernatants were collected, and virion DNAs were extracted and analyzed. *, P < 0.05 (compared with isotype IgG). The x-axis data for panels E and F are as indicated for panels B and C, respectively.