Ik^L/L mice do not produce IFNα upon stimulation with influenza virus or TLR ligands. (A) Purified CD11c⁺ spleen cells were stimulated with inactivated influenza virus (Flu) or CpG D19 for 24 hours, and supernatants were tested for the indicated cytokines. Results represent 1 of 2 experiments, on cells pooled from 5 mice/genotype per experiment. (B) Mice were injected with poly I:C, R848, or CpG 1668. Sera were collected at 2 hours (R848) and 4 hours (PBS, poly I:C, CpG) after injection and tested for the indicated cytokines. Results are representative of 2 experiments, with 3 mice/genotype per condition for each experiment. Means and SDs are shown for 1 representative experiment.