Expression of stromal cell-derived factor 1α protein in HIV encephalitis

Abstract Analysis of the patterns of stromal cell-derived factor 1α (SDF-1α) expression in the brains from HIV-positive patients suggests that in neuronal cells, SDF-1α might play a role in neuroprotection and neurite extension in response to HIV infection. In all cases analyzed, SDF-1α immunoreactivity was primarily present in astroglial cells. Patients with HIV encephalitis (HIVE) showed intense somato-dendritic neuronal SDF-1α immunoreactivity, while HIVE negative patients with neurodegeneration had a significant decrease in neuronal SDF-1α immunoreactivity. Neuronal cells treated with SDF-1α displayed increased neurite outgrowth. Similarly, neurons treated with HIV-Tat, which induced SDF-1α expression, also showed neurite outgrowth. Tat-mediated neurite outgrowth was blocked by anti-SDF-1α antibody. These results suggest that SDF-1α may play a role in the neuronal response to HIV in the brains of AIDS patients.