The effect of an RGD-containing fusion protein CBD-RGD in promoting cellular adhesion.

The effect of a recombinant RGD (arginine-glycine-aspartic acid)-containing fusion protein, cellulose-binding domain (CBD)-RGD, on the cellular adhesion to a biomedical polyurethane (PU) was evaluated. A series of different cell lines, as well as freshly harvested animal cells, were grown on the PU surfaces with or without CBD-RGD, in serum or serum-free media. The results showed that the enhancement of cellular attachment by CBD-RGD varied with cell types. This is believed to be a result of the unique integrin receptors on each type of cell surface. The existence of certain divalent ions (Mg2+ and Mn2+) may increase the efficacy of the CBD-RGD, in a cell type-dependent manner. The fusion protein was also found to inhibit the platelet activation. The effect of CBD-RGD was further examined in two other substrate materials, poly(L-lactide) (PLLA) and poly(lactide-co-glycolide) (PLGA). The effect on cellular adhesion correlated with the amount of CBD-RGD physically adsorbed on the material surface.