Effect of antiviral substances on hepatitis A virus replication in vitro.

The effect of protamine, atropine, selenocystamine, taxifolin, and catechin on the infectivity and antigenicity of the cell culture-adapted hepatitis A virus (HAV) strain CF 53 was studied. The toxicity on uninfected PLC/PRF/5 cells was examined for each antiviral compound by morphological and biochemical methods, in order to determine concentrations without cytotoxic effect. At these concentrations, protamine and taxifolin, added to infected cells for a 15-day period, caused concentration-dependent reductions in the infectivity and antigenicity of HAV. Atropine also caused a concentration-dependent reduction of HAV infectivity but did not affect the antigenicity of the virus. At the highest concentration used, 50 micrograms/ml of protamine, 59 micrograms/ml of taxifolin, and 50 micrograms/ml of atropine, the infectious viral titer reduction was 1.56, 0.77, and 0.68 log10, respectively. Selenocystamine and catechin had no effect on HAV replication.