HIV-associated chronic immune activation: current understandings and therapeutic intervention

The mechanisms by which HIV causes AIDS remain poorly understood. However, the generalized immune dysfunction associated with progressive HIV infection is clearly related to the levels of immune activation, which results in increased target cells for the virus, excessive apoptosis of uninfected T cells and, paradoxically, an impaired ability to control HIV replication. The causes of this chronic, aberrant immune activation are complex and are the consequences of both virus replication and the resultant immune damage and dysfunction. Of note, natural SIV hosts, which do not progress to AIDS despite lifelong infection, do not show chronic immune activation. Here we discuss the causes and consequences of the HIV-associated chronic immune activation, and potential therapeutic approaches to lower its impact.