To characterize the molecular structure of the human cytomegalovirus (HCMV) DNA maintained in cultures of human retinal glia following ganciclovir treatment and to determine the biological activity of the DNA.
Cultures of human retinal glia were established, infected with HCMV, treated with ganciclovir, and embedded in agarose, and the viral DNA was analyzed by field inversion gel electrophoresis.
The HCMV DNA was found to persist in cultures of infected, ganciclovir-treated retinal glial cells in the form of replicative intermediates. After removal of ganciclovir, processed forms of DNA in the 500- to 1000-kilobase range were found as well as 230-kb unit length genome. Infectious virus was recovered after termination of ganciclovir treatment.
The data are consistent with the concept that ganciclovir's virostatic nature permits maintenance of HCMV DNA in retinal glia in a biologically active form that is capable of replication after removal of the drug.