hOSCAR is an endocytic receptor of mono-DCs. Human serum–saturated mono-DCs were incubated with the following primary antibodies at 4° C for 30 minutes: (A) anti-CD13 mAb (negative control), (B) DC-GM1 mAb specific for mannose receptor (positive control), and (C) whole mAb and (D) F(ab′)2 specific for hOSCAR. After incubation with biotin-conjugated goat F(ab′)2 anti-mouse, cells were transferred at 37° C to allow endocytosis (□). At the indicated times, the cells were stored at 4° C, and the remaining surface receptors were detected by incubation with PE-conjugated streptavidin. PFA-fixed cells (▪) and cells kept at 4° C during the entire time period (▴) were used as negative controls of active endocytosis. Data shown are representative of 5 independent experiments and display the mean and standard deviation of 3 independent samples.
