Human cytomegalovirus infections in vitro after treatment with arildone

Arildone (WIN 38020), a broad spectrum antiviral, aryl-beta-diketone (4-[6-(2-chloro-4-methoxy)phenoxyl]hexyl-3,5-heptanedione), blocks the replication of human cytomegalovirus at a stage prior to the synthesis of virus-specific DNA. Inhibitory action was demonstrated against a number of virus isolates from neonates and immune-compromised patients. Intranuclear sites of virus replication, highlighted by DNA-staining methods or immunofluorescence, were absent after Arildone treatment and corresponded with the lack of ultrastructural changes associated with productive infection. The abundance of early antigens in cells treated with Arildone was evidence for expression of the viral genome and this was confirmed by detection of immediate-early viral proteins in the presence of the drug. The results suggest that Arildone prevents the replication of human cytomegalovirus at a stage after virion uncoating but prior to viral DNA synthesis.