Myofibroblastic-activated hepatic stellate cells are the major source of the collagen I-rich
extracellular matrix in liver fibrosis but also produce matrix metalloproteinases, which
remodel this protein. We have investigated the role of collagen I proteolysis in both
regulating proliferation and maintaining the activated myofibroblastic phenotype of stellate
cells in vitro. Compared with stellate cells plated on normal collagen I, those plated on a
collagenase-resistant form of collagen I (r/r collagen) had reduced thymidine incorporation …