Nevertheless, in the acute phase of infection, the key roles are played by interferon-gamma (IFN-γ), interleukin 1 alpha (IL-1α), interleukin 7 (IL-7), interleukin 9 (IL-9), interleukin 10 (IL-10), granulocyte colony-stimulating factor (G-CSF), fibroblast growth factor (FGF), granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-α), and vascular endothelial growth factor (VEGF). Here, IL9 is linked to infection.