Insights into the role of immune activation in HIV neuropathogenesis

How does HIV infection lead to the development of central nervous system disease? Central to this question is identification of the relative contributions of (1) the virus, (2) its host cells, and (3) secondary or downstream events to the pathological process. These are re-examined in this brief review. Also, a greater appreciation for the role of systemic events in neuroinflammation is emerging, with likely relevance to HIV-associated dementia. We propose here a model for HIV neuropathogenesis that highlights the role of systemic monocyte activation and subsequent neuroinvasion in initiating the disease.