Inhibition of NF-κB activity by ritonavir.

KSIMM cells were transfected with a NF-κB luciferase reporter construct and an expression vector encoding HIV-Tat protein (pCV1-Tat) (A) or HHV8 ORF74 (pSG5-ORF74) (B). Twenty hours after transfection, cells were treated with indicated amounts of ritonavir and luciferase activity was measured 6 hours later. (C) Luciferase readings derived from cells that were activated with TNF and treated with ritonavir simultaneously. Values shown are averages derived from 3 independent cultures, with SDs represented by the error bars. These experiments were repeated twice with similar results. Autoradiography (D) of EMSAs for NF-κB activation. Monocytes were treated with indicated concentrations of ritonavir and activated with TNF-α (10 ng/mL) for 20 minutes. Double-stranded NF-κB consensus oligonucleotide and nuclear protein extracts reacted for 30 minutes and products were separated in 4% polyacrylamide gel electrophoresis. Lane 1: activated, untreated control; lane 2: not activated, untreated control; lane 3, activated, treated with 1 μmol/mL ritonavir; lane 4: activated, treated with 5 μmol/mL; lane 5: treated with 25 μmol/mL.