CD4 and DC-SIGN expression on blood DC.

(A) CD4 and DC-SIGN surface expression on blood DC subsets. Blood DCs were freshly isolated as outlined in “Materials and methods.” The mAb to CD4 (Leu3a) or DC-SIGN (AZN-D1) was added and then incubated and detected as outlined in Figure 4. Cultured DCs were DC-incubated overnight in the presence of interleukin-3/GM-CSF. Blood DC subsets were further distinguished by CD11c staining. (B) DC-SIGN expression on blood DCs by RT-PCR. Top panel: ethidium bromide–stained gel (top) of PCR products for DC-SIGN from cDNA. Lane 1: 1-kilobase ladder; lane 2: CD11c^+ve blood DCs; lane 3: CD11c^−ve blood DCs; lane 4: monocytes; lane 5: MDDCs; lane 6: MDDCs cultured with lipopolysaccharide; Lane 7: PBMCs; lane 8: H₂O. Bottom panel: the autoradiograph of the Southern blot probed with a digoxigenin oligonucleotide specific for DC-SIGN.