FIGURE 2.

Weak IL-12 response to superantigen in CD40L-deficient mice. (A) Serum IL-12 heterodimer from 5C.C7-1 RAG2^−/− (WT) (n = 14) or 5C.C7-1 RAG2^−/−CD40L^−/− (n = 26) mice 6 h after i.v. injection with 10 μg SEA, or saline, as indicated. ***p < 0.001. (B) Same conditions as (A), except that serum IL-2 was measured. Student t tests were computed between WT and CD40L^−/− groups for both IL-12 and IL-2. (C) BMDCs from B10.A-RAG2^−/− mice were preactivated with 200 ng/ml LPS for 21 h, then washed and adjusted to 2 × 10⁴ cells per well prior to coculture with 1 × 10⁵ cells per well 5C.C7-1 RAG2^−/− Ag-activated (WT) or CD40L^−/− T cells plus 0.1 μm MCC in the presence or absence of cytokines at 100 ng/ml for 48 h in 96-well plates. CSN were tested for the presence of IL-12. These data are expressed as the mean ± SD in triplicate wells representative of two independent experiments.