Fig. 3

Potential cell candidates with high ECM degradation ability. A Schematic of cells with degradation ability, including fibroblasts, endothelial cells, macrophages, neutrophils and tumor cells. B Collagen degradation ability of primary murine skin fibroblasts isolated from wild-type or Mmp14^−/− mice was detected after they were cultured on type I collagen gels by Coomassie Blue staining (Sabeh et al. 2009). C Collagenolytic activity of human umbilical vein endothelial cells (HUVECs). HUVECs transfected with cav-1-mRFP were grown on a reconstituted basement membrane containing fluorescein conjugated-collagen IV. Confocal images were taken of cav-1-mRFP (red), substrate degradation products (green) and live cells (DIC) (Cavallo-Medved et al. 2009). Scale bars, 20 μm. D Endocytosis of fluorescein conjugated-collagen (green) by RAW 264.7 macrophages (Ford et al. 2019). Scale bars, 20 μm. E Collagenolytic activity of exosomes from activated or quiescent polymorphonuclear leukocytes was measured by culturing them with FITC-labeled type I collagen (Genschmer et al. 2019). F Collagen degradation ability of squamous carcinoma cells (SCC1) cultured with or without TIMP2. SCC1 cells (red) were labeled with propidium iodide and degraded collagen (green) was stained with mAb HUI77 (Hotary et al. 2003). B–F is reused with permission from Elsevier