Figure 4.

IPCs induce proliferation and IFN-γ production by antigen experienced unpolarized T cells. (A) Proliferative response of 3A9 T cells expanded by CD11b⁺ DCs to graded numbers of primary unstimulated DCs, IPCs, or B cells. 3A9 T cells were restimulated 9–10 d after the first stimulation. (B) IFN-γ and IL-4 production in 3A9 T cells restimulated with primary unstimulated IPCs, CD8α⁺, and CD11b⁺ DCs. The percentage of positive cells and mean fluorescence intensity of IFN-γ–producing cells are indicated. (C) Quantitation of IL-12p70 in supernatants of T cell-DC and T cell–IPC cocultures. Supernatants were collected after 24 h and IL-12p70 was measured by ELISA.