A significantly increased MCTC expression of TGF-β was observed in all compartments analysed: IPF (small airways: 84 [75-100]%, pulmonary vessels: 100 [83-100]% and alveolar parenchyma: 100 [50-100]%) and controls (small airways: 8 [0-50]%, p = 0.0008; pulmonary vessels: 0 [0-50]%, p = 0.005; and alveolar parenchyma: 0 [0-20]%, p = 0.004). Here, TGFB1 is linked to idiopathic interstitial pneumonia.