Murine gammaherpesvirus 68 infection of gamma interferon-deficient mice on a BALB/c background results in acute lethal pneumonia that is dependent on specific viral genes.

Gamma interferon (IFN-gamma) is critical for the control of chronic infection with murine gammaherpesvirus 68 (gammaHV68). Current data indicate that IFN-gamma has a lesser role in the control of acute replication of gammaHV68. Here, we show that IFN-gamma-deficient mice on the BALB/c genetic background poorly control acute viral replication and succumb to early death by acute pneumonia. Notably, this acute, lethal pneumonia was dependent not only on the viral dose, but also on specific viral genes including the viral cyclin gene, previously identified to be important in promoting optimal chronic infection and reactivation from latency.