TAT and HIV infectious disease: As activation of immune cells has been shown in primate models of HIV infection and in gp120-induced rodent models of HIV-SN23,37,70,71,81 and has been linked to Tat-induced neurotoxicity in vitro16,43,62,66,80 and in vivo,8,24,36,46 we assessed immune cells in the DRG and spinal cord.