Neurotoxicity is a pathological phenomenon seen in neuroHIV that was also observed through transfer of cell-free CM from Ephb2 activated microglia onto neurons, which our data suggest is a consequence of the assortment of pro-inflammatory secreted factors (IL-6, CXCL10, TNFα, IL-1β etc.). The gene discussed is EPHB2; the disease is toxic encephalopathy.