This study was undertaken to investigate the immunomodulatory mechanisms of statins that target the IFN response in PDCs.We isolated human blood PDCs by flow cytometry and examined the effects of simvastatin and pitavastatin on PDC activation, IFNalpha production, and intracellular signaling.Statins inhibited IFNalpha production profoundly and tumor necrosis factor alpha production modestly in human PDCs in response to Toll-like receptor ligands