Human Brain Astrocytes Mediate TRAIL-mediated Apoptosis after Treatment with IFN-γ

TNF-related apoptosis inducing ligand (TRAIL) expressions were studied in primary human brain astrocytes in response to pro-inflammatory cytokines. When astrocytes were treated with IL-1β, TNF-α or IFN-γ, TRAIL was induced in cultured fetal astrocytes. In particular, IFN-γ induced the highest levels of TRAIL in cultured astrocytes. When astrocytes were prereated with IFN-γ, they induced apoptosis in TRAIL-sensitive Peer cells. Our results suggest that IFN-γ modulates the expression of TRAIL in astrocytes, which may enhance cytotoxic sensitivity of infiltrating immune cells or brain cells other than astrocytes during inflammation of brain.