Simple radiometric techniques for rapid detection of herpes simplex virus type 1 in WI-38 cell culture

Two radiometric techniques were developed for detecting the presence of herpes simplex virus type 1 in stationary monolayers of the diploid cell line WI-38. The time of detection was compared to that obtained from visual examination for cytopathic effects in the same cell line. Oxidation of 14C-1-glucose in infected and uninfected cells was determined by 14CO2 production, measured by an ionization chamber, and DNA synthesis was determined by 3H-thymidine incorporation, measured by scintillation counting. Compared to uninfected cells, infected cells showed a 23-26% reduction in 14C-1-glucose oxidation and a 355-498% increase in DNA synthesis 4-6 hr after infection. These changes in cellular metabolism were observed 14 hr before visible signs of cytopathic effects. The increase in DNA synthesis was completely inhibited by viral neutralization with herpes simplex antiserum. Increased DNA synthesis was observed 5 hr after infection with 10,000-3,200,000 TCID50 units of virus. These radiometric methods for the detection of viral effect on cellular metabolism are simple, fast, and objective.