Fig. 3.
DC immunization in the absence of B7-H1 eliminated tumors carrying dominant Ag but encouraged the emergence of tumors carrying subdominant Ag. (A) Schematic representation of vector design for pEGFP-N1 with the insertion of a minigene encoding OVA peptide (Left) and pDSRed-N1 with the insertion of a minigene encoding H-Y peptide (Right). (B) B6 mice were immunized twice at days −14 and −7 with BM-derived DCs from WT or B7-H1–KO male/OVA-Tg mice. Mice were challenged i.d. with an equal mixture of 5 × 106 EL4-OVA/EGFP and EL4-HY/DSRed. Tumor growth is presented as a percentage of incidence (Left) and as mean tumor diameter (Right). (C) Tumors were surgically excised at day 50, and cells were analyzed by flow cytometry for EGFP and DSRed. (D) B6 mice were immunized s.c. with WT or B7-H1–KO DCs coloaded with gp100 and TRP2 and were inoculated i.d. with B16 cells. Mean tumor diameters (Left) and the mortality (Right) were recorded.