ITIH4 and HIV-associated neurocognitive disorder: Neuronal injury observed in HAND occurs indirectly through the release of neurotoxic, proinflammatory host factors predominantly from microglia and astrocytes, which are productively infected by HIV [2, 31, 32], or as a direct neurotoxic effect of soluble HIV proteins shed from infected host cells and virus such as gp120 [12, 33, 34, 81].