Extracellular matrix components such as collagen, fibronectin and sulphated glycosaminoglycans can act as substrata that promote neural crest motility in vitro, in the absence of serum. The cells appear to be less adhesive and move more randomly on collagen or chondroitin sulphate substrata than on fibronectin substrata. Cells do not spread or become motile on plastic dishes to which hyaluronate has been bound, presumably owing to weak adhesion to this surface. Hyaluronate added to the medium alone has little effect on cell motility. When combinations of matrix molecules are used as substrata, however, the presence of fibronectin increases spreading, directional persistence of cell motility and speed of movement above that observed on collagen alone. When added to fibronectin, chondroitin sulphate appears to reduce adhesions slightly, since the cells are more rounded. Hyaluronate added in the medium significantly reduces the extent, speed and directionality of movement on fibronectin substrata. The presence of collagen in combination with fibronectin plus glycosaminoglycans does not have a noticeable effect on cell motile behaviour, beyond that observed with fibronectin alone. The effects of combinations of matrix compounds on neural crest cell motility are thus predictable, and can be explained in terms of the known adhesive properties and reported binding interactions of these molecules. These studies in vitro are compared with neural crest cell motility in vivo.
Age related extracellular matrix and interstitial cell phenotype in pulmonary valves
