SERT expression is coupled to DC functional maturation. (A) BMDCs were incubated for 2 days with LPS (50 ng/mL), cross-linked anti-CD40 mAb (5 μg/mL), or CD152/Fc (40 μg/mL), or left untreated. Solid histograms show the expression of CD86 and MHC II molecules by gated, CD11c⁺ BMDCs relative to isotype controls (dashed histograms). (B) Immature (CD11c⁺ CD86^-) BMDCs were sorted and were cultured for 2 days as described. IL-6 and IL-12 concentration in the culture supernatants was determined by ELISA for treated BMDCs (▪) relative to untreated controls (unT; □). Data are means ± SD from triplicate assays (n = 3; ^*P < .05, t test). (C) The expression of SERT mRNA relative to GAPDH controls was examined by RT-PCR for each treatment group prepared as described in panel B. The optical density of each band relative to untreated BMDCs was determined and normalized for GAPDH signal. Data are representative of 2 independent experiments.