IL6 and atherosclerosis: Reduced atherosclerosis and AAA in mast cell-deficient KitW-sh/W-sh mice can be fully restored by reconstituting these mice with mast cells from WT and Tnf−/− mice, but not those from Il6−/− or Ifng−/− mice, suggesting an essential role of mast cell IL6 and IFN-γ, but not TNF-α in atherosclerosis and AAA.