Learning From AIDS
There are similarities between the progression of AIDS and what happens (more slowly) to our immune systems with aging. Forced overactivation and exhaustion of resources are the focus here. AIDS researchers are making steps towards understanding mechanisms that would allow the immune system to be tuned down for specific threats, to prevent it grinding itself into oblivion. "During both HIV infection in humans and SIV infection in macaques, the host immune system becomes highly activated, experiences increased destruction and decreased production of key immune effector cells and progressively fails as a result. In contrast, natural hosts for SIV infection, like sooty mangabeys, do not exhibit aberrant immune activation and do not develop AIDS despite high levels of ongoing SIV replication. ... sooty mangabeys, dendritic cells produce much less interferon alpha - an alarm signal to the rest of the immune system - in response to SIV. As a result, the dendritic cells are not activated during the initial or chronic stages of SIV infection, and mangabeys fail to mount a significant immune response to the virus." It seems reasonable to expect this knowledge to be applicable to the long-term response to CMV in humans, an important contributer to age-related immune system failure.
Link: http://www.sciencedaily.com/releases/2008/09/080916143900.htm