Viral chemokine-modulatory proteins: tools and targets

The chemokine network is an extensive system that regulates many immune functions such as leukocyte locomotion, T cell differentiation, angiogenesis and mast cell degranulation. Tight control of chemokines is vital for proper immune function. Not surprisingly, viruses have found ways to subvert or exploit the immune system in order to persist in co-existence with their hosts. Several viral immune evasion genes encode proteins that modulate the chemokine network. We attempt to identify which aspects of the chemokine control mechanisms are susceptible to modulation. Chemokine-glycosaminoglycan interaction, extracellular processing of chemokines and chemokine scavenging will be discussed in the light of poxvirus and herpesvirus immune evasion. Viral chemokine-modulatory proteins may either be targets for anti-viral therapy or lead the way to new anti-inflammatory chemokine-modulating drugs.