CD86 and infection: Given that, as indicated above, viral doses of MVA-B higher than 1 PFU/MDDC caused a high cell death rate of MDDC at 48 h post-infection, while 0.33 PFU/MDDC at 16 h post-infection appeared as the optimal dose for the upregulation of CD86 and other maturation markers of MDDC, we next compared the highest viral dose, 10 PFU/MDDC, and the optimal dose, 0.33 PFU/MDDC for the effects on maturation and cell viability.