ABSTRACT
It has been proved that the peptide sequence Arg-Gly-Asp (RGD) in cell adhesion proteins such as fibronectin and vitronectin is crucial for the attachment of many cells to these proteins [1, 2]. Fibronectin is the best characterized multifunctional glycoprotein mediating cell-extracellular matrix interactions, and plays an impor tant role in cell adhesion [3, 4]. Recent research on vitronectin in blood plasma revealed that it exists in two forms of molecular weight 75 000 and 65 000 Da, and plays a major role in the cell adhesion and spreading activity of serum [5-7]. It was also pointed out that for an oxygen-containing fluoropolymer film, the attachment and spreading of human vein endothelial cells in serum-containing medium was very dependent upon the vitronectin content of the serum but was substantially indepen dent of the fibronectin content of the culture medium [8]. For nitrogen-containing films, however, the attachment of human vein endothelial cells was not simply dependent upon either the vitronectin content of the serum, or the fibronectin content [8]. The only homology between the two glycoproteins is the RGD sequence, as described above.
