Viruses in control of the immune system

Viruses have evolved strategies to evade the inflammatory and immune responses that their hosts have co-evolved to limit viral impact on reproductive fitness (Alcami and Koszinowski, 2000; Tortorella et al., 2000). The number of viral immune evasion strategies identified has increased dramatically in recent years. These rely on proteins that mimic or target specific components of the immune system or that prevent immune recognition of virally infected cells. We are only just beginning to comprehend the subtleties of virus–host interactions, which is of obvious importance for the understanding of viral pathogenesis. This workshop brought together scientists who view the interactions between viruses and host defence mechanisms from different perspectives. The aim was to discuss strategies of immune modulation employed by viruses, focusing primarily on two large DNA virus families—herpesviridae and poxviridae— whose members are particularly adept at manipulating immunity, and human immunodeficiency virus (HIV), which is highly successful in modifying the immune system despite its smaller genome (Table I). Particular emphasis was placed on gleaning insights into the normal functions of the immune system based on the viral immunomodulatory effects. We are rapidly approaching a time when we will be able to apply this knowledge to design better vaccines and treatments for viral infections and autoimmune diseases.