MR mediates omega-1–induced DC modulation and Th2 polarization in vitro. After 1-h preincubation with blocking antibodies against MR, DC-SIGN, or an isotype control (20 µg/ml), human moDCs were pulsed for 16 (A) or 48 h (B–D) with 500 ng/ml natural omega-1 (ω-1) in combination with 100 ng/ml LPS. (A) Protein synthesis was assessed as described in Fig. 5 B. One representative experiment based on duplicate samples out of three experiments is shown. Data are shown as mean ± SD. (B) The expression levels of CD86 on human DCs assessed by FACS are based on geometric mean fluorescence, relative to the DCs stimulated with LPS alone, which is set to 1 (dashed line). Data are based on three independent experiments and shown as mean ± SD. (C) Conditioned human DCs were co-cultured for 24 h with a CD40-L–expressing cell line to mimic the interaction with T cells. IL-12p70 cytokine expression levels are shown relative to the DCs stimulated with LPS alone, which is set to 1 (dashed line). Data are based on three independent experiments and shown as mean ± SD. (D) Conditioned human moDCs were cultured with allogeneic naive CD4⁺ T cells for 12 d in the presence of staphylococcal enterotoxin B and IL-2, and T cell polarization was analyzed as described in Fig. 1. FACS plots of one representative experiment out of six are shown. Bar graphs are based on six independent experiments and represent mean ± SD. (E) Murine splenic WT or MR^−/− DCs from a C57BL/6 background were co-cultured with naive BALB/c CD4⁺ T cells in the presence 2 µg/ml omega-1. After an expansion with rIL-2 at day 3, T cells were restimulated on day 6 with PMA and ionomycin and analyzed for intracellular cytokines. One representative experiment out of three is shown. * and #, P < 0.05; **, P < 0.01; *** and ###, P < 0.001 for significant differences with the LPS control (*) or between test conditions (#) based on paired analysis (two-sided paired Student’s t test).