Figure 3.

Nitrotyrosine staining in astroglial cells either untreated (a) or pre-treated with supernatants of HIV-1-infected macrophages (b,c,d). In particular, the supernatant of HIV-infected macrophages enhanced the immunocytochemical expression of nitrotyrosine (b), indicating an increased production of peroxynitrite. Incubation of cells with FeTMPS (c) but not with the inactive catalyst H₂TMPS (d) inhibited HIV-related peroxynitrite formation in astrocytes. These are representative photomicrographs (optical microscopy 40×) out of four independent experiments.