Figure 1. TP219 inhibits virus morphogenesis.

(A) Structural formula of TP219. (B) Effect of TP219 on cell viability and CVB3-induced cytopathic effect in BGM cells. Toxicity (black circles) and CPE (white squares) was quantified by MTS assay at 3 d p.i. and expressed as percentage of untreated controls. Data are average values ± SD. (C) Analysis of the effect of TP219 on RNA replication and infectious virus titers. BGM cells were infected with RLuc-CVB3. The indicated compounds were added immediately after infection at the indicated concentrations. The enterovirus inhibitors GuaHCl and geldanamycin were included as controls. At 8 h p.i. intracellular viral RNA replication in the absence or presence of the indicated molecules was quantified by measuring luciferase activity (C, left panel). Lysates were used to determine infectious virus yields calculated by endpoint titration and expressed as the tissue culture 50% infectious dose per ml (TCID₅₀) (C, right panel). Experiments were performed in triplicate and mean values ± SD are depicted. (D) Effect of TP219 on polyprotein processing. Cells were infected with CVB3 at MOI 50 and pulse-labeled with Methionine ^3S[S] in the absence or presence of TP219. Subsequently, proteins were analyzed by SDS-PAGE.