Figure 4.

CD40 signaling in SEA DCs augments their capacity as APCs. Day six DCs were stimulated with medium alone (-), SEA, LPS or CpG with or without addition of agonistic anti-CD40 Ab for 19hrs. Cells and supernatant were then harvested and assessed for A. IL-12p40 production by ELISA. B. Antigen processing capacity as previously described. C. Surface expression of MHC class II and CD86. D. Day six WT or CD40^-/- DCs were pulsed with ovalbumin protein for 1hr prior to extensive washing to remove extracellular protein. Cells were then stimulated for 19hr with SEA before being co-cultured with CFSE labeled naïve CD4⁺ purified DO.11.10 T cells. After 3 days, cells were harvested by assessed for proliferation by CFSE dilution. Data are mean ± SEM from at least 3 individual experiments