Structural basis of the herpesvirus M3-chemokine interaction.

Viruses have been fighting the immune systems of their hosts for millions of years and have evolved evasion strategies to ensure their survival. Viruses can teach us efficient mechanisms to control the immune system, and this information can be used to design new strategies of immune modulation that we might apply to diminish immunopathological responses that cause human diseases. Large DNA viruses, such as poxviruses and herpesviruses, encode proteins that are secreted from infected cells, bind cytokines and neutralize their activity. A subgroup of these viral proteins binds chemokines, a complex family of cytokines that control the recruitment of cells to sites of infection and inflammation. One of the major unresolved questions in the field was to understand how these viral secreted proteins bind chemokines with high affinity, despite having no amino acid sequence similarity to the host chemokine receptors, which are seven-transmembrane-domain proteins that cannot be engineered as soluble proteins.