Advances of immunological pathogenesis research in HIV related neurocognitive disorder

Abstract

With extended life of HIV-infected patients due to highly active anti-retroviral therapy (HAART), the rate of HIV associated neurocognitive disorder (HAND) remains high and attracts much attention. The evidence is clear that cytokines are elevated in the blood of patients with HIV infection, which contribute to elevating the permeability of blood-brain barrier. Benefiting from that, cells in the brain are infected with HIV that has accelerated through the blood-brain barrier both as cell-free virus and infected immune cells including monocytes and T cells. Upon migration into the central nervous system, HIV-infected monocytes and T cells not only infect brain resident cells but also produce proinflammatory cytokines such as TNF and IL-1ß, which further activate microglia and astrocytes. These activated brain glial cells and perivascular macrophages, which release inflammatory mediators, are the main contributors to neuroinflammation resulting in neuronal dysfunction. The pathogenesis of HAND is multifaceted, however, mounting evidence indicates that HIV related neuroinflammation plays a major role, which should be the focus of therapeutic research for HAND in future.