For example, V2O5-induced lung fibrosis in mice features Th1 inflammation and elevated levels of interferon-γ (IFN-γ) and IFN-inducible cytokines along with elevated levels of profibrogenic growth factors (PDGF-CC, CTGF, TGF-β1) and collagen with no apparent increases in IL-13 [74]. This evidence concerns the gene IL13 and pulmonary fibrosis.