Antiherpetic activity of test compounds in cell culture.

<p>Confluent HEL cell cultures were exposed to 100 TCID₅₀ of clinical virus isolates [wild-type HSV-1 (panel A), wild-type HSV-2 (panel B), TK⁻ HSV-1 (panel C) and TK⁻ HSV-2 (panel D)] in the presence of drugs at different concentrations and incubated for 3 days at 37°C. Then, the cytopathicity was determined microscopically and the EC₅₀ values determined. ^aEC₅₀, 50% effective concentration or compound concentration required to reduce virus-induced cytopathicity (CPE) by 50%. Data shown are the means of at least two independent experiments. The HSV-1, HSV-2, HSV-1 TK⁻, and HSV-2 TK⁻ clinical isolates have been described in reference 19, including the nature of the mutations in the TK gene of the acyclovir-resistant virus strains.