Figure 2.

Rhamnogalacturonan II (RG-II) activates both mitogen-induced protein kinases and nuclear translocation of nuclear factor-κB and induces cytokine production (interleukin (IL)-12, IL-1β, tumor necrosis factor-α (TNF-α) and interferon-γ IFN-γ)) during DC maturation. Bone marrow-derived dendritic cells (BMDCs) were treated with 0.5 mg ml⁻¹ RG-II for 5, 15, 30 or 60 min. (a) Cell lysates were prepared and blotted with anti-phospho-ERK1/2, anti-ERK1/2, anti-phosopho-p38 and anti-p38 antibodies. (b) Nuclear extracts (NEs) were blotted with anti-phospho-p65 (Thr 254) antibody and cytosolic extracts (CEs) were also blotted with anti-I-κB antibody. BMDCs incubated with lipopolysaccharide (LPS; 200 ng ml⁻¹) were used as a positive control. (c) BMDCs were stimulated with LPS (200 ng ml⁻¹), RG-II (0.25–1 mg ml⁻¹) or RG-II (0.5 mg ml⁻¹) in the presence of LPS for 24 h. Cytokine concentrations in culture supernatants were measured in triplicate by enzyme-linked immunosorbent assay (ELISA). The mean (s.e.m.) values shown represent three independent experiments. *, ** And *** indicate significant differences at P<0.05, P<0.01 and P<0.001, respectively, compared with unstimulated cultures (NS, not significant).