Growth of Human Endothelial Cells on Different Concentrations of Gly‐Arg‐Gly‐Asp Grafted Chitosan Surface

Abstract

To improve the adhesion and growth of endothelial cells on chitosan, different concentrations of cell adhesive peptide, Gly-Arg-Gly-Asp (GRGD), were photochemically grafted to its surface. After different concentrations of GRGD-SANPAH (N-Succinimidyl-6-4'-azido-2'-nitrophenylamino]-hexanoate) solutions were formed, they were grafted to chitosan surfaces by performing surface adsorption of the peptide solutions and subsequent ultraviolet (UV) irradiation to induce photoreaction. The grafted efficiency for GRGD peptide to chitosan surface was higher than 80%, as semiquantitatively analyzed by a high performance liquid chromatography (HPLC). FTIR spectra and electron spectroscopy for chemical analysis (ESCA) also confirmed that GRGD was successfully grafted to form chitosan-GRGD surfaces. For example, the composition fraction of nitrogen (N1s) for chitosan-GRGD surface grafted at 0.05 M GRGD was 6.8% instead of 3.2% for chitosan only. Human umbilical vein endothelial cells (HUVECs) adhered well and grew on different GRGD grafted concentrations of chitosan-GRGD surfaces after 36 hrs of incubation, but not on the chitosan surface. Furthermore, viability for the growth of HUVECs was increased with an increase in initial concentration of GRGD grafted chitosan-GRGD surfaces analyzed by MTT assay. In conclusion, an increased concentration of GRGD grafted on the chitosan-GRGD surface leads to more HUVECs adhered and grown on the surface.

Mechanotransduction in endothelial cell migration

“…Aside from interacting with integrins, fibronectin also binds to transmembrane HSPG (e.g., syndecan-4) at the cell surface via motifs in repeats 12-14 such as Pro-Arg-Ala-Arg-Ile (PRARI), which act in concert with fibronectin-integrin binding to stimulate FA formation [Beyth and Culp, 1984;Woods et al, 1986;Woods et al, 1993]. With increasing trends toward the fabrication of novel biomaterials (e.g., vascular grafts and stents) for vascular repair, the peptides derived from CBDs such as RGD have been immobilized on the engineered surface to enhance EC attachment and spreading [Lin et al, 1994[Lin et al, , 2001Chung et al, 2003]. By conjugating RGD peptides on non-fouling surfaces, we have demonstrated the increase of EC adhesion and spreading with the increase of RGD density, but no significant effects are detected for EC proliferation [Patel and Li, unpublished observation], suggesting that the minimal RGD density to support EC proliferation has a very low threshold.…”

Biologically Active Chitosan Systems for Tissue Engineering and Regenerative Medicine

“…Three different approaches have been investigated to introduce beneficial bioactivity to chitosan by using the reactive hydroxyl and amine groups of chitosan. In addition, photochemical reactions can occur between the hydroxyl groups on chitosan and azido derivative of peptides to form covalent bonding [45,46]. For example, negatively charged heparin molecule can be introduced to chitosan systems by ionically interacting with positively charged chitosan molecules [35].…”

“…Growth factors such as BMP-2 were chemically immobilized on a nanofibrous chitosan substrate as a guided bone regenerative membrane [43] in contrast to the physical adsorption method illustrated previously [48]. In this regard, oligopeptides containing RGD (Arg-Gly-Asp) sequences from fibronectin have been covalently coupled on chitosan substrates [38,39,42,45,46]. The chemically bound BMP-2 remained bioactive and was more effective in stimulating osteoblastic cell proliferation and differentiation as compared to the BMP-2 adsorbed chitosan membrane.…”

Branched chitosans: Effects of branching parameters on rheological and mechanical properties

“…[36][37][38][39] In this study, we conducted short-term investigations of the vascular SMC response to the linear and branched chitosans. No apparent differences were observed in cell adhesion or proliferation on the various materials.…”