Figure 5.

SEA induced antigen processing occurs independently of MyD88 and Trif. DCs were generated from MyD88-/- and Trif-/- mice and grown for 6 days. Cells were then pulsed with HRP as previously described prior to 19hrs chase in the presence of either medium alone, SEA, CpG or PolyI:C. The levels of intact HRP remaining after 19hr was assessed allowing the antigen processing capacity of A. MyD88-/- DCs and B. Trif-/- DCs to be determined. Significant differences by Student's t test (* p<0.05, ** p<0.01), where data points represent mean value ± SD of data from three experiments. C. The role of Trif was investigated further by examining the ability of SEA to inhibit LPS or CpG induced IL-12p40 production in its absence. WT and Trif-/- DCs were pulsed with LPS (L) or CpG (C) alone or in combination with SEA (S), or with SEA alone, and 24hr later IL-12p40 levels in culture supernatants we measured by ELISA. The suppression of TLRligand induced cytokine production by SEA is in each case significant by Student's t test (p<0.05). D. Trif-/- DCs were tested for their ability to induce Th2 responses. Splenocytes from mice immunized as indicated in the X-axis were restimulated with SEA, and levels of IL-13, as an indicator of Th2 response development, were measured by ELISA. Control DCs were not pulsed with SEA. Data points represent mean values from 3 individual mice/group ± SD.