IFNG and hydrops fetalis: In their time course studies, they reported that metabolic disturbances were evident after 6 wks of an HF diet (60% fat) and that activated macrophage markers are also present at 6 and 8 wks (F4/80 and CD11c) [17], while interferon-γ (IFN-γ) and interleukin (IL)-12p40 were not significantly altered by the HF diet after 4 or 8 wks of feeding [17] nor were TNF-α or MCP-1 after 4 or 8 wks [18].