The nature of the humoral immunity induced by targeting DC using anti-mClec9A mAb. C57BL/6 or (A) C57BL/6 TRIF−/−MyD88−/− or (B) C57/BL6 FcRγ−/− or (C) C57/BL6 nu/nu mice were injected intravenously with 10 μg of the anti-mClec9A mAb (10B4) or the nontargeted isotype control mAb-2 (GL117). (D) C57BL/6 mice were injected intravenously with 10 μg of the anti-mClec9A mAb or isotype control mAb-2 (GL117), either with or without lipopolysaccharide (LPS; 10 ng). (E) Ten micrograms of OVA-conjugated anti-mClec9A mAb or OVA-conjugated isotype control mAb-2 (GL117) or (F) escalating doses of free OVA were injected intravenously into C57BL/6 mice. Serum anti–rat Ig Ab titers were measured by ELISA at week 4. Each circle represents an individual mouse, the geometric mean of the group is depicted by a line. Experiments were performed 2 to 4 times with similar results, with the exception of panel E, which was performed once.