MMP9 and idiopathic pulmonary fibrosis: In addition, the same group performed laser-assisted microdissection of airway lesions in both CLAD and IPF explant lungs, and reported a large and important molecular overlap of pivotal fibrotic pathways, with shared upregulation of TGF-β, MMP-9, RANTES, TIMP-1, TIMP-2, BMP-2, PLA-1 and COL1/2/3 (6).