The effect of SLAM molecules on the induction of cell-surface receptors concomitant with CD40L-induced maturation of DCs. (A) Immature DCs were cultured in the presence of CD40L-L cells or SLAM/CD40L-L cells for 24 hours. Cell-surface expression of HLA-DQ, CD83, and CD86 was determined by flow cytometry. Histograms obtained when using specific antibodies (filled areas) or isotype-identical controls (open areas) are shown. MFI indicates mean fluorescence intensity; FITC, fluorescein isothiocyanate. (B) IDCs were cultured with or without sCD40L for 24 hours in the presence of SLAM-L cells or the SLAM^– parental cell line. CD40L was added at concentrations indicated. Cell-surface expression of CD83 and CD86 molecules on DCs was analyzed by FACS. The ratio of CD83⁺ and CD86^high DCs was calculated using the indicated gates (histograms). The ratio of CD83⁺ and CD86^high DCs at different sCD40L concentrations in the presence of SLAM⁺ or SLAM^– L cells is shown. Representative results of 3 independent experiments are shown.