NEUROPATHOGENESIS OF SIMIAN IMMUNODEFICIENCY VIRUS-INFECTION IN MACAQUE MONKEYS

Patients infected with human immunodeficiency virus (HIV) develop immu nologic dysfunction and multiorgan inflammatory diseases directly asso ciated with HIV-1 infection. Of these inflammatory diseases, the most devastating to the HIV-infected patient is involvement of the central nervous system (CNS). The pathogenesis of the clinical syndrome observ ed in these patients, termed HIV-associated dementia, remains poorly u nderstood. However, as most of the detectable virus in the CNS is in c ells of monocyte/macrophage lineage, it is clear that penetration of t he blood-brain barrier by HIV-1 and the subsequent influx of monocytes into the brain are crucial components in the neuropathogenesis of HIV -associated dementia. Using the SIV-infected macaque model of acquired immunodeficiency disease, much has been learned about viral neuroinva sion occurring soon after experimental infection. The aim of this revi ew is to discuss these recent advances and provide insight into plausi ble mechanisms for monocyte entry into the CNS.