Figure 5. C-di-AMP preferentially activates human myeloid dendritic cells (DCs) in vitro.

PBMC-derived human plasmacytoid DCs (pDC) or myeloid (conventional) DCs (mDC) were incubated for 24 h in the presence of 60 µg/ml c-di-AMP or without additive (control). (A) Cells were decorated with fluorochrome-conjugated antibodies specific for the identification markers CD11c (mDC), CD303 (pDC) CD80, CD83 and CD86, and analyzed by flow cytometry. Normalized median fluorescence intensity (MDFI) is shown as fold increase compared to the control. Error bars show SEM for n = 3. (B) The medium from the cultured mDC or pDC was analyzed for IFN-β secretion by ELISA. Error bars show SEM for n = 3. Differences are statistically significant at p<0.001 (***) or p<0.05 (*).