ABSTRACT
The effect of cytomegalovirus on the metabolism in monolayers of human embryonic lung fibroblasts (WI-38 cells) was studied. Effects of viral infection were examined by comparing [3H] thymidine incorporation in infected cells with that in uninfected cells. The time for detecting changes in cellular metabolism using the radiometric method was compared with that for observing cytopathic effects in infected cells. Compared with uninfected cells, cells infected with 10(4) TCID50 of virus showed nearly 400% increased in [3H] thymidine uptake 48 hr after infection. The radiometric method was able to detect 10(3) TCID50 of virus, with about 250% stimulation, 24--48 hr before visible signs of cytopathic effects. Our results suggest that with further development, radiometric measurement of metabolism in cytomegalovirus-infected cell cultures might provide a means of detecting viral presence in clinical assays. The radiometric method has the advantage of objectivity and potential for automation.
