IL-12p40 is produced at similar levels by normal (WT) and WASp-null (WAS) CD11c⁺CD8α⁺ DCs in response to STAg 6 hours after injection. Arrows indicate the gated CD11c⁺ splenocytes expressing CD40 or IL-12 after STAg challenge; this expression is absent in PBS-treated spleens. An isotype-matched rat IgG2a control antibody produced a staining pattern identical to that seen with the PBS control (data not shown). Data presented are from 1 of 2 independent experiments with similar results.