FIG 4.

Effects of neomycin on CVB3-Nancy replication kinetics. Shown is the growth curve in the presence of liquid media (A) or agar overlay (B). Briefly, 1 × 10⁶ HeLa cells that had been pretreated or not with neomycin were inoculated with CVB3-Nancy at an MOI of 0.01. Virus was incubated for 30 min at 37°C, and either DMEM liquid (A) or 1% agar–1% DMEM mixture (B) with or without neomycin was added. At the indicated time points, intracellular virus was harvested and quantified by plaque assay. For panels A and B, n = 4 or 5 total data points from two independent experiments. To examine multicycle replication and spread, cells were infected with 100 PFU of CVB3-Nancy and either DMEM (C) or 1% agar–1% DMEM mixture (D) with or without neomycin, followed by plaque assay of cell-associated virus. For panels C and D, n = 6 total data points from three independent experiments. (E) HeLa cells were pretreated or not with 1 mg/ml of neomycin prior to plating of 100 PFU of CVB3-Nancy on cells with agar overlays with or without 1 mg/ml of neomycin. Plates were stained with crystal violet 48 hpi. *, P < 0.05 (unpaired two-tailed Student t tests). Images are representative of results from two independent experiments.