Role of mononuclear phagocytes and accessory cells in human immunodeficiency virus type I infection of the brain.

The cells responsible for persistence of viral infection in the brains of human immunodeficiency virus type I-positive individuals are most likely mononuclear phagocytes. The infection of other cell types within the brain is presumably the result of close interactions with HIV-I-producing cells of the mononuclear phagocytic lineage. During these interactions, both direct effects from HIV-I infection of brain cells as well as indirect mechanisms (namely the response of brain cells to the presence of virus-infected cells, particularly monocytes and macrophages) should be considered. In addition, the genomic variability of HIV-I could play a role in increasing the tropism of the virus for certain cell types.