Mechanism of inhibition of HSV-1 replication by tumor necrosis factor and interferon γ

Abstract

Tumor necrosis factor (TNF) synergizes with interferon (IFNγ) in the blockade of HSV-1 replication. Antibodies against IFNβ block this synergism, implying a role of IFNβ in the antiviral activity of TNF plus IFNγ. IFN β 1 added exogenously to Hep-2 cells shows antiviral activity against HSV-1 only at high concentrations, whereas IFN β 2 (also known as IL-6) alone has no effect on the replication of VSV or HSV-1 even when 1,000 U/ml are present. Our results are in accordance with the idea that TNF induces IFN β 1 and that both cytokines must be present in the culture medium to synergize with IFNγ in order to inhibit HSV-1 replication.