Poly I:C stimulation induces activation of NFκB in endothelial cells and RA synovial fibroblasts but not in dendritic cells and macrophages. (A) Human DCs, MØs, ECs, RA-SFs, and (B) murine DCs were infected for 1 hour with an adenovirus carrying an NFκB luciferase reporter gene. The cells were stimulated for 6 hours with 100 ng/mL LPS or poly I:C (in μg/mL) as indicated and then analyzed for luciferase activity. The data are mean values (± SD) from triplicates and are representative of at least 3 experiments using cells of different donors.