ANGIOGENIC OLIGOSACCHARIDES OF HYALURONAN ENHANCE THE PRODUCTION OF COLLAGENS BY ENDOTHELIAL-CELLS

The present study demonstrates a relationship between angiogenic oligo saccharides of hyaluronan (HA) and the production of collagens during the process of angiogenesis in vivo and in vitro. The addition of angi ogenic oligosaccharides of HA to the chorioallantoic membrane of the c hick embryo induced a deposition of collagen fibrils. The treatment of sub-confluent cultures of bovine aortic endothelial cells with the sa me oligosaccharides (I mug/ml) increased the uptake of [H-3]proline by approximately 60%. SDS-polyacrylamide gel electrophoresis of treated cultures demonstrated the enhanced synthesis of type I and type VIII c ollagens. The production of type VIII collagen was confirmed by wester n blotting and immunocytochemistry using antibodies to sheep and bovin e type VIII collagen. Type VIII collagen is a short chain collagen tha t has a high degree of homology to cartilage-specific type X collagen. The biological functions of type VIII and type X collagens are unknow n. We have suggested that the two collagens play a role in the process of angiogenesis.