CD40 and HIV-associated neurocognitive disorder: Furthermore, CD40-CD40L signaling has been implicated in HIV-associated neuroinflammation previously: Ramirez et al. observed an increase in CD40 expression on BMVECs from patients who had succumbed to infection and been diagnosed with HIV encephalitis compared to BMVECs from control brains [24], indicating that endothelial cells in patients with HAND-related complications are highly responsive to excess amounts of sCD40L.