IL18 and hydrops fetalis: As shown in Figure 1A, mRNA levels of ET-1, tumor necrosis factor (TNF)-α and interleukin (IL)-6 were significantly increased in alveolar macrophages from HF patients (n = 20) relative to controls (n = 16), but not gene expression of IL-1β, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory peptide (MIP)-1α and IL-18.