Figure 5

Vpr peptides (aa 70-96) exert neuroimmune and neurotoxic effects. Exposure of ΔVpr77Q-HAD (5.0 μM) or ΔVpr77R-ND (5.0 μM) to human microglia resulted in ΔVpr77R-ND-mediated induction of (A) IFN-α, (B) MX1, (C) PRKRA and (D) BST-2 transcripts. Similarly, human astrocytes exposed to the same peptides showed induction of (E) IFN-α, (F) MX1 and (G) PRKRA expression. (H) Exposure of ΔVpr77R-ND to human neurons caused a concentration-dependent (10.0-60.0 μM) reduction in β-tubulin immunoreactivity while ΔVpr77Q-HAD showed less neurotoxicity. Full length Vpr (1.0 μM) was also highly neurotoxic. Experiments were carried out in triplicate at least two times (A-D, Dunnett test, relative to control; *p < 0.05, **p < 0.01).