TGFB1 and pulmonary emphysema: In particular, we demonstrate that in mice BLM-treated which are genetically deficient in αl-PI (i) emphysema and fibrosis may coexist either in different areas, or in a same lung area; (ii) the development of emphysema precedes that of fibrosis; (iii) the development of emphysematous lesions, shortly after BLM administration, is preceded by an alveolar elastolytic burden and is matched by a marked decrease in lung desmosine content; and finally, (iiii) an evident staining for TGF-β and TGF-α is observed when an increased neutrophil elastase burden can also be demonstrated.