PKC activator (bryostatin) and MAPK inhibitor protected against CXCL10- and HIV-1-induced neurotoxicity. (A) HFN cultures were immunostained for CXCR3 (green) and CXCR4-PE (red), then counterstained with DAPI (n = 3). (B) Dose response of bryostatin for toxicity; HFA cultures were treated with increasing concentrations of bryostatin (0 to 100 nM). LDH was estimated in supernatants 48 h post-treatment. (C-D) HFN were pretreated with bryostatin (25 nM), CXCR3 blocking monoclonal antibody (5 μg/ml), or MAPK inhibitor SB203580 (5 μM), then insulted with a combination of (C) HIV-1 and CXCL10 or (D) HIV-1 alone. At 24 h post-treatment, LDH activity was monitored in supernatants. H2O2 was used as a positive control (n = 2). PKC, protein kinase C; MAPK, mitogen-activated protein kinase; HFN, human fetal neurons; DAPI, 4',6-diamidino-2-phenylindole; HFA, human fetal astrocytes; LDH, lactate dehydrogenase.