Fig. 1

Immune cells-mediating HIV neuroinvasion. To date, four immune cell types are described to support HIV invasion into the CNS. Those include CD14 + CD16 + monocytes, perivascular macrophages, CD4 + T cells, and CD4^dimCD8^bright T cells. CD4^dimCD8^bright T cell may invade the brain as such, or the phenotype is generated in the brain as CD8 + T cells enter the brain and through the Wnt-rich environment in the CNS induce CD4 expression on their surface. These HIV-infected immune cells then released HIV in the brain to support infection of microglia and to a lesser extent, non-classical infection, of astrocytes.