CD69 is upregulated on endogenous DC upon activation.

<p><b>A.–C.</b> DC were purified from spleens of C57BL/6 mice and cultured with CpG in various conditions. 10 γg/ml of anti-CD69 2.2 were added to control samples in order to block CD69 staining and provide a background staining control. 10 µg/ml of Isotype control Ab were added to test samples. All samples were stained for the different DC subsets markers and for CD69, and analyzed by flow cytometry. <b>A.</b> Overlay of CD69 expression between CD69 blocked control samples cultured with 0.03 µM CpG for 18h (grey filled), and unblocked samples, uncultured (dashed line) or cultured with 0.03 µM CpG for 18h (solid line), gated on pDC (CD11c^int, CD45RA⁺), and cDC (CD11c^hi, CD45RA⁻). <b>B.</b> DC were cultured with 0.03 µM CpG during various time-spans and CD69 was assessed in pDC (CD11c^int, CD45RA⁺) and cDC (CD11c^hi, CD45RA⁻). <b>C.</b> pDC (CD11c^int, CD45RA⁺), CD8⁺ cDC (CD11c^hi, CD45RA⁻, CD8⁺) and CD8⁻ cDC (CD11c^hi , CD45RA⁻, CD8⁻) were analyzed for CD69 expression after 12h culture with different doses of CpG or without having been cultured. In B and C, CD69 levels are expressed as the difference of CD69 MFI between the unblocked and blocked samples. Results representative of two similar experiments are shown.