Varicella-zoster virus infection induces the secretion of interleukin-8

Interleukin-8 (IL-8) is an important mediator in neutrophil-mediated acute inflammation but has also a wide range of actions on various cells types. We demonstrated that infection of melanoma cells and fibroblasts with cell-associated varicella-zoster virus (VZV) and infection of a T cell line with cell-free VZV resulted in an induction of IL-8 secretion in vitro. The inhibition of the VZV replication with a drug interfering with its DNA replication had no effect on the IL-8 release. Since the IL-8 promoter contains binding sites for NF-κB and AP-1, melanoma cells and the T cell line were treated with inhibitors of NF-κB, JNK/SAPK or p38/MAPK prior to infection. In melanoma cells, the JNK/SAPK pathway was shown to be important for the IL-8 secretion during the VZV replication, whereas in the T cell line, not only the JNK/SAPK but also the p38/MAPK pathways were required for IL-8 secretion. The neutralisation of the IL-8 bioactivity had no significant consequence on the VZV replication, suggesting that IL-8 acts neither as a proviral nor as an antiviral cytokine during the VZV replication in vitro.