Collagens are proteins present in all tissues. Besides their structural role, recent data showed that they were able to regulate many cellular functions. Many interactions occur between extracellular matrix macromolecules, especially collagen, and various cell types. These interactions can be controlled by peptides derived extracellular matrix macromolecules, called matrikines. Previous work from the investigators laboratory and others have shown that several C-terminal domain (NC1 domains) from basement membrane-associated collagens could regulate many cellular activities.