Figure 1.

Depiction of cells in the brain and their interactions with HIV. (A) HIV+ macrophages (purple) circulate through the blood brain barrier and pass through into the CNS, where they can release viral particles and infect microglia (yellow). (B) direct contact with infected macrophages infects astrocytes (orange), which have the capability to pass viral infection to other astrocytes. Anti-HIV responses by astrocytes are much more potent in the cortex than in the cerebellum, therefore leading to a greater number of HIV+ cells in the cerebellum than in the cortex. (C) HIV+ macrophages and microglia, as well as astrocytes stimulate a powerful inflammatory response against infection (red dots), leading to damage and death of neurons (pink) and oligodendrocytes (green). (D) Circulating infected CD4+ T cells are trafficked into the brain and can infect glial cells via direct contact. (E) theorized route of infection from the meningeal lymphatic system, where HIV+ monocytes (blue) stimulate inflammation to permeabilize the vessels and carry infection into the CNS independent of the blood brain barrier. Created with BioRender.com.