FIG 2.

Replication of DENV-2 clades under selective pressure by MPA treatment. Equal numbers of GE of five viral isolates from each DENV-2 clade were used to infect Aag2 cells with the addition of either MPA or an equivalent amount of methanol alone following a 2-h adsorption period. The data are plotted as the mean and standard error of the mean. (A) Number of GE/ml for five isolates at 3 dpi in the presence or absence of MPA, as indicated. Statistical significance was determined by a paired t test: for NI-1, P < 0.001 (*); for NI-2B, P = 0.0810 (no significant difference [n.s.]). (B) Reduction in viral titer for each clade in the presence versus absence of MPA according to the formula number of GE with MPA/number of GE without MPA. Significance was determined using the Mann-Whitney test (*, P = 0.037).