New n' Hot: Cell Exhaustion in Chronic Viral Infections

Researchers from the Emory Vaccine Center have discovered that chronic viral infections, like HIV and Hepatitis C, actually exhaust the body's immune system. Despite a strong immune response in the patient, these viruses essentially "tire out" T-helper cells after a period of time. Here's how it works:

- T-helper cells find out that a virus is present when they detect bits of virus presented by MHC class I molecules
- These researchers found that mice with a LOWERED ability to present viral proteins to T-cells were initially healthier, because their bodies detected less virus
- BUT the T-Helper cells of these mice became exhausted--and useless--much sooner, because they could not recognize the virus in cells unable to present virus-bits
- T-helper cells presenting MORE viral protein experienced exhaustion LESS


Original article:
http://www.sciencedaily.com/releases/2009/05/090513173459.htm

-Molly