AVS 51st International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI-MoP

Paper BI-MoP30
Development and Characterization of RGD Peptide Coatings for Cell Adhesion

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: R. Canteri, ITC-irst, Italy
Authors: R. Canteri, ITC-irst, Italy
C. Pederzolli, ITC-irst, Italy
L. Lunelli, ITC-irst, Italy
P. Villani, ITC-irst, Italy
L. Pasquardini, ITC-irst, Italy
M. Vinante, ITC-irst, Italy
G. Speranza, ITC-irst, Italy
S. Forti, ITC-irst, Italy
M. Anderle, ITC-irst, Italy
J.J. Park, University of Maryland
G.W. Rubloff, University of Maryland
Correspondent: Click to Email
The development of biomaterials able to modulate the interaction of mammalian cells with solid substrates is important for many applications, e.g., tissue replacement/regeneration and substrates for cell culture. A common mechanism that mediates cell adhesion involves the interactions between integrin receptors on the surface of mammalian cells and ligands of adhesive proteins present in extracellular matrices (ECM) and bloodstream. These proteins include fibrinogen, fibronectin, vitronectin, collagen, laminin, Von Willebrand factor. It has been demonstrated that the adhesive domains comprise a short peptide sequence, Arg-Gly-Asp (RGD), the most important recognition site for about half of all known integrins. This work describes a three-step reaction procedure for coupling a six-amino-acid (GRGDSY) fibronectin fragment synthesized with an additional cysteine (C) at the C-terminus, to solid substrates. The first step is the activation of the substrate with an amine layer, introduced by chemical modification (silanization) or by using an amino-containing biopolymer (chitosan). In a second reaction step, N-hydroxysuccinimidyl (NHS) ester polyethylene glycol (PEG) is grafted to the aminated surfaces. Fluorescence quantitative showed 1-5 x10@super 13@ PEG molecules/cm@super 2@ immobilized on the surface. The distal end of these PEG molecules carry two possible chemical groups: a maleimide or a vinylsulfone group, both selectives for reaction with sulfhydryl groups. The final step is the covalent attachment of RGD-containing peptides on the resulting terminal PEG derivatives. XPS, ToF-SIMS, AFM, SEM, fluorescence spectroscopy and microscopy were applied to characterise the surface. The RGD modified surfaces were tested using different cell lines. The results obtained on the functionalized surface showed an higher extent of cell adhesion, with mainly round-shaped cells at the initial stage of the spreading, compared to the non-modified surface.