DCs were generated in the presence of IL-3 and IFN-β and were activated with 3T6-CD40L transfectants for 3 days or LPS (1 μg/mL) for 24 hours or with influenza virus for 24 hours or Poly (I:C) for 48 hours. IFN-α levels in supernatants were measured by ELISA, and results were expressed as means ± SEM of independent experiments on different blood donors.