MODULATION OF MORPHOLOGICAL-DIFFERENTIATION OF HUMAN ENDOTHELIAL-CELLS IN CULTURE BY THE SYNTHETIC PEPTIDE YIGSR AND CYTOCHALASIN-B

Matrigel is a solubilized tissue basement membrane gel extracted from the mouse Engelbreth-Holm Swarm sarcoma. Cultures of human endothelial cells could be induced to undergo extremely rapid morphological diffe rentiation into capillary-like structures by Matrigel. The present stu dy demonstrates the following: (a) Matrigel-induced tube formation by endothelial cells is laminin-dependent and, particularly, the YIGSR pe ptide site in the B1 chain of laminin may be necessary for endothelial cell differentiation resulting in capillary formation; (b) endothelia l cells may be preprogrammed for rapid differentiation into blood vess els and do not require DNA, RNA or protein synthesis in order to under go tube formation on Matrigel; and (c) microfilament assembly and func tion is important for Matrigel-induced tube formation.