MMP8 and idiopathic pulmonary fibrosis: To confirm these results and identify the cell types in which MMP-8 is regulated in IPF lungs, we double immuno-stained lung sections from explanted IPF lungs and rejected normal lung transplant donor lungs using a green fluorophore for MMP-8 and a red fluorophore for markers of epithelial cells, macrophages, neutrophils, or fibroblasts.