In a study reported in the Proceedings of the National Academy of Sciences, a group led by Allan Lau, and Michael Yeung, scientists in the Department Of Pediatrics at UCSF, has shown that a virus can establish a persistent infection if it can overcome cell suicide, an important host defense. And they have shown that once the virus establishes a lasting presence in the host's cells, physiological changes begin. The discovery could lead to methods to find new antiviral agents, to boost the effectiveness of antiviral drugs - and possibly to end Hepatitis C and other persistent viral infections.
Some viruses later change their tactics from invader to dominator.
The virus takes over part of the cell's machinery and dwells there, becoming a persistent infection. Persistent viral infections can continue for life and wreak slow havoc, as HIV does to the immune system and Hepatitis B and C do to the liver. Now Lau, Yeung and their colleagues have taken a virulent, cell-killing virus and converted it to a persistently infective virus. In the initial experiments that led to this model, Lau said, the scientists expected that suppressing cell suicide would allow the virus to produce more copies of itself and spread more effectively. What we didn't expect was that this would cause the virus to become less of a killer, and to convert to a persistent infectious agent.