Biomimetic nanofibrous scaffolds provide an ideal surface to volume ratio and abundant binding ligands to enhance EC adhesion. Alternatively, circulating ECs can be captured with immobilized monoclonal antibodies against CD34. Studies performed in vitro with implants coated with anti-CD34 antibody in a functionalized multilayer containing heparin-collagen revealed enhanced viability and metabolic activity relative to non-antibody functionalized surfaces. Additionally, in vivo experiments showed less neointimal hyperplasia compared with non-functionalized surfaces. Other studies examined surfaces coated with vascular endothelial growth factor receptor (VEGFR) to capture ECs on hydroxyl terminated poly (ethylene-co-vinyl alcohol) surfaces. VEGFR surface coating significantly increased the number of cells expressing VEGF after 2 weeks in culture and induced their differentiation (Figure ). Alternatively, coating grafts with active peptides with simple structures and high stability has been shown to promote EC adhesion. The most employed peptide is Arg-Gly-Asp (RGD), which was identified as the minimal essential cell adhesion peptide sequence in fibronectin. RGD can be immobilized on the surface of biomaterials by binding to hydroxyl, amino, or carboxyl groups (Figure ). Studies have shown that a high RGD density promotes rapid proliferation of ECs, which can be controlled using bioactive motifs such as Lys and glycine molecules at the N-terminus of peptides that act as spacers (Figure ). Although promising, RGD peptide also promotes the adhesion of platelets, thus novel peptides need to be screened with selective binding biofunctions to the special integrins in ECs. 11 Different immobilization methods of RGD peptide on biomaterial surfaces by activation of the carboxyl acid groups on the material's surface with NHS; activation of the hydroxyl groups on the material's surface with p-nitrophenyl carbonate; thiol-RGD peptide reacts with acrylic derivatives via the Michael addition reaction; thiol-RGD peptide reacts with maleinimide via the Michael addition reaction; immobilization of the RGD peptide via the azido-alkyne click reaction. c) Cell adhesion on nanopatterned surfaces with various nano spacings with cells stained red for F-actins, green for vinculins, and blue for nuclei, wherein the top and middle rows reveal low-magnification and high-magnification fluorescent micrographs of smooth muscle cells cultured on nanopatterns for 24 h. Bottom graphs show the statistical results of the cell adhesion. 11