Curdlan-induced CTL priming by DCs is dependent on IL-12 p70. (A) Cocultures of OT-I T cells and C57BL/6 BMDCs in the presence of 30 pM SIINFEKL peptide and the indicated stimuli and either anti–IL-12 p40 blocking antibody or isotype-matched control antibody. (B) As in panel A but comparing C57BL/6 with IL-12 p40–deficient BMDCs in the absence of blocking antibodies. (C) As in panel A but with anti–IL-23 p19 blocking antibody or isotype-matched control antibody. (D) As in panel B, with either C57BL/6 or IL-23 p19–deficient BMDCs. (E) As in panel B, with either C57BL/6 or IL-12 p35–deficient BMDCs. IFN-γ levels were measured in day 3 culture supernatants (B-E) or after restimulation of total day 3 cultures with SIINFEKL-loaded targets (A). Similar results were obtained with and without restimulation (not shown). Data in all panels are mean plus SD of duplicate or triplicate wells.