TGFB1 and pulmonary fibrosis: Additionally, bleomycin-insulted mice showed increased lung levels of TGF-β1 (Figure 3A) and total collagen concentration (Figure 3B), as measured by ELISA, and increased lung expression of COL1A1 (Figure 3C) and α-SMA (Figure 3D), as assessed by Sircol Collagen Assay kit or Western blot analysis; all these are indices of pulmonary fibrosis.