Murine IFN-α–producing cells are present in the lymphoid, CD11c⁺CD11b⁻ DC population.

(A) Myeloid (CD11c⁺CD11b⁺) and lymphoid (CD11c⁺CD11b⁻) DCs were sorted from spleens of mice mobilized for 7 days with Flt3L+GM-CSF using the directly conjugated CD11c-PE and CD11b-APC antibodies. T and B cells depleted by antibodies to CD3 and surface immunoglobulin and directly conjugated goat anti–rat IgG–coated magnetic beads. FITC-labeled antibodies to CD3 and sIgM were used to further exclude contaminating cells in FACS sorting. Gates were set to exclude dead cells and debris. Purity of sorted cells typically exceeded 97%. (B) CD11c⁺CD11b⁺ (black columns) and CD11c⁺CD11b⁻ (white columns) DCs were cultured for 24 hours in medium alone or with HSV (5 PFU/cell) or SAC (10 μg/mL). Supernatants were collected and analyzed for IFN-α₂ and IL-12 (p70) by specific ELISA. Lymphoid CD11c⁺CD11b⁻ contained the major IFN-α activity after stimulation with HSV. SAC induced IFN-α and IL-12 production. Data from 1 of 3 experiments with similar results are shown.