FIGURE 4.

Preexisting Epstein–Barr virus (EBV) infection facilitates DENV-2 propagation in Akata and THP-1 cells. (A,B) Equivalent amount of EBV + Akata or EBV- Akata cells were mock-infected or infected with DENV-2 at a multiplicity of infection (MOI) of 10. Growth kinetics of DENV-2 were determined by plaque assay and plotted as in panel A. DENV-2 E protein expression level at 24 and 36 hpi was quantified by immune blot (B). (C) Schematics illustration of the experimental workflow. Low-molecular weight fractions (<100 kDa) of the culture supernatants from EBV + and EBV- Akata cells were incubated with THP-1 cells for 8 h. Differently primed THP-1 cells were referred to as EBV + T and EBV- T, respectively, in panel D. (D) The primed THP-1 cells were then infected with DENV-2 at a MOI of 10, and DENV-2 titers in the culture medium at 36 and 48 hpi were determined by plaque assay.