Effect of cloned human interferons on the replication of and cell fusion induced by herpes simplex virus.

Human alpha- and beta-interferons, expressed from cloned genes, block the replication of, and cell fusion induced by herpes simplex viruses. This inhibition is neutralized by antiserum to interferon and demonstrates species specificity. The block in replication appears to be late in the replication cycle of herpes simplex virus, since similar levels of viral DNA are synthesized in both interferon-treated and untreated cells.