Fibronectin and avidin-biotin as a heterogeneous ligand system for enhanced endothelial cell adhesion.
A preadsorbed layer of "heterogeneous" integrin-dependent and -independent protein was used to enhance initial integrin-mediated endothelial cell attachment and spreading. Glass substrates were treated with fibronectin (Fn) and avidin coupled through adsorbed biotinylated bovine serum albumin (b-BSA). The slides then were seeded with biotinylated BAEC. Control "homogeneous" surfaces were slides adsorbed with either Fn or avidin coupled to b-BSA. The cells were incubated for 0.5 h in serum-containing media and exposed to a range of shear stresses in a laminar flow variable-height flow chamber. The critical shear stress to detach 50% of the seeded cells on the heterogeneous ligand surface was significantly greater than for either of the control homogeneous ligand systems (p < 0.001). Cellular spreading during the initial period of 0-2 h also was higher (p < 0.05) on the heterogeneous ligand-treated surface than on the surface of either of the homogeneous controls. The close contact area of the cell membrane with the substrate 1 h after seeding in serum-containing media was measured using TIRFM. Cells attached onto the heterogeneous ligand-treated surfaces had a significantly (p < 0.01) higher area of close contact with the substrate, which is consistent with a greater degree of attachment and spreading. The results indicate that the combination of integrin-dependent and -independent adhesion systems using heterogeneous ligands further enhances initial endothelial cell attachment and spreading.
Bhat
V D
VD
Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708-0281, USA.
Truskey
G A
GA
Reichert
W M
WM
D000818:Animals; D001360:Avidin / Q000378:metabolism*; D001710:Biotin / Q000378:metabolism*; D002417:Cattle; D002448:Cell Adhesion; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism; D005353:Fibronectins / Q000378:metabolism*; D016023:Integrins / Q000378:metabolism; D008024:Ligands
D005353:Fibronectins; D016023:Integrins; D008024:Ligands; D001360:Avidin; D001710:Biotin