Figure 1.

[³H](R)-PK11195-specific binding is higher in HIVE brain tissues compared to controls and corresponds to HIV-infected and activated macrophages. A and B: Representative saturation binding curves (A) and Scatchard plots (B; X-intercept represents B_max, and slope represents K_D) with [³H](R)-PK11195 from the mid-frontal cortex of human patients with HIVE (black squares), HIV no-encephalitis (gray squares), and age-matched controls (clear squares). C: B_max (fmol/mg protein, y axis), reflective of the total number of [³H](R)-PK11195 binding sites/mg protein in HIVE (n = 5, black bars) compared to noninfected controls (Con, n = 3; clear bars) and HIV infected, without encephalitis (HIV no E, n = 5; hatched bars) frontal cortical brain tissue (P = 0.0006). D: [³H](R)-PK11195 binding affinity (K_D, nmol/L, y axis) in HIVE (n = 5, black bars) compared to noninfected controls (Con, n = 3; clear bars) and HIV infected, without encephalitis (HIV no E, n = 5; hatched bars) frontal cortical brain tissue (P = 0.2296). E: [³H](R)-PK11195 B_max (fmol/mg protein, y axis) in primary human astrocytes activated with 100 μmol/L dB-cAMP, treated with 1 μg/ml of LPS for 48 hours, or treated with HIV for 7 days compared to untreated controls (n = 3, each condition). B_max was also measured in primary human macrophages activated with either 1 μg/ml of LPS or 300 IU of IFN-γ for 48 hours and infected with HIV for 7 days compared to untreated controls (n = 3, each condition). F: [³H](R)-PK11195 K_D (nmol/L protein, y axis) in primary human embryonic astrocytes activated with 100 μmol/L dB-cAMP, treated with 1 μg/ml of LPS for 48 hours, or treated with HIV for 7 days compared to untreated controls. K_D values in primary human macrophages activated with either 1 μg/ml of LPS or 300 IU of IFN-γ for 48 hours or infected with HIV for 7 days compared to untreated controls. All data were analyzed using one-sided analysis of variance, ***P < 0.0001, **P < 0.001, and *P < 0.01.