Expression of costimulatory and MHC molecules on FV-infected DCs. (A) Myeloid DCs were generated from the bone marrow of FV-infected BALB/c mice and analyzed for the expression of cell-surface molecules. CD11c-gated DCs were stained for FV glycosylated Gag protein using mAb 34 and for costimulatory molecules, maturation maker CD83, or MHC molecules. The infected cells are in the right quadrants, whereas uninfected cells are shown in the left quadrants. The different populations were from the same culture of DCs generated from an infected mouse. The percentage of cells positive for the different DC markers in both the infected and uninfected populations of DCs is given in the top quadrants. A flow cytometric analysis representative for more than 10 independent DC cultures is shown. (B) Myeloid DCs were generated from the bone marrow of FV-infected or uninfected BALB/c mice and stimulated in vitro with IFNα (1000 U/mL) or poly(I:C) (100 μg/mL). Afterward, CD11c⁺-gated DCs were stained for the expression of the costimulatory molecule CD86 as a surrogate marker for DC maturation. The histogram on the left shows the mean fluorescence intensity (MFI) of uninfected cultures, whereas the right histogram shows the results for FV-infected DC cultures. The gray curves represent the isotype control for the CD86 staining. The lower histogram shows the CD86 staining of uninfected or infected DCs that were not treated (no IFN or poly(I:C)). A flow cytometric analysis representative for 6 independent DC cultures is shown.