Figure 6.

Peptide-pulsed DCs induce a vigorous CD8⁺ T cell response that can be inhibited by OT1 T cell transfer. Bone marrow was removed from the major leg bones of B6 mice, T and B cell depleted, and cultured with IL-4 and GM-CSF for 8 d. ova8 peptide was added to the cultures at 5 μg/ml for 2 h at 37°C. The resulting DCs were harvested and injected intravenously into B6 recipients at 10⁶/mouse. On days 5, 7, and 9 after DC injection, the spleens were harvested and stained with K^b/ova8 tetramer. (A) Dot plots from the day 5 time point gated on live, CD8⁺class II⁻ events. Companion stains showed the Kb/ova8 tetramer staining cells to also be predominantly blasts and CD25⁺ at only the day 5 time point, and L-selectin^lo and CD44^hi at all time points (data not shown). (B) Tetramer staining histograms of live, CD8⁺class II⁻CD44^hi gated events of spleen cells from DC-challenged mice analyzed at the times indicated after initial DC challenge. (C) Mice immunized as in A with (+OT1) and without (No trans) the transfer of 5 × 10⁵ OT1 T cells.