Induction of IFN-γ protein and transcript by IL-18 plus IL-12.

Four- to 6-week-old C57BL/6 mice (A) or C.B-17 SCID mice (B) received IP injections of IL-18 plus IL-12, and their spleens were harvested at 24 hours. Splenocytes were cultured for 4 hours in brefeldin A, permeabilized, stained with DX5-PE mAb (pan-NK) and anti–muIFN-γ–FITC mAb, and analyzed by flow cytometry with the use of a mononuclear cell gate. (C) Real Time RT-PCR analysis of SCID splenocytes for IFN-γ and IL-10 transcripts at various times after IP injection of IL-18 plus IL-12.