Maturation of splenic DCs in vivo. (A) FACS analysis of MHC II (left) and CD86 (right) expression in freshly purified splenic DCs from untreated (black line), LPS-injected (red line), or CpG-injected (blue line) mice. The dashed line corresponds to unlabeled DCs. (B) ICM analysis of MHC II localization in freshly purified splenic DCs from untreated (left), LPS-injected (center), or CpG-injected (right) mice. (C) The indicated number of DCs freshly purified from untreated, LPS-, or CpG-treated mice was used in an assay of antigen presentation to the anti-HEL T-cell hybridoma BO4H9.1 (left) and the anti-OVA T-cell hybridoma OT II (right). (D) The indicated number of freshly purified and fixed DCs was assessed for its capacity to induce OT-II proliferation in the presence of the OVA_323-339 peptide.