Abstract
HIV-1 replicates in monocyte-derived cells in multiple organ systems; in the central nervous system, productive infection is confined to monocyte lineage cells in the brain. In addition, productive viral infection takes place in the choroid plexus, where the incidence of infection is actually higher than in brain and is present prior to the onset of AIDS and immunosuppression. Restricted or latent infection occurs in astrocytes and neurons. The presence of perineuronal CD4+ lymphocytes, as well as activated microglia, support the potential for a trans-receptor mechanism of viral entry whereas intrinsic gene profiles do not appear to participate in conferring selective neuronal vulnerability or resistance to infection.