NEURONAL CELL ATTACHMENT TO FLUORINATED ETHYLENE-PROPYLENE FILMS WITHCOVALENTLY IMMOBILIZED LAMININ OLIGOPEPTIDES YIGSR AND IKVAV .2.

Material surfaces that can mediate cellular interactions by the coupli ng of specific cell membrane receptors may allow for the design of a b iomaterial that call control cell attachment, differentiation, and tis sue organization. Cell adhesion proteins have been shown to contain mi nimum oligopeptide sequences that are recognized by cell surface recep tors and can be covalently immobilized on material surfaces. In this s tudy, cell attachment to fluorinated ethylene propylene (FEP) films fu nctionalized with the laminin-derived oligopeptides, YIGSR and a 19-me r IKVAV-containing sequence, was assessed using NG108-15 neuroblastoma and PC12 cells. A radiofrequency glow discharge (RFGD) process that r eplaces the FEP surface fluorine atoms with reactive hydroxyl function alities was used to activate the film surfaces. The oligopeptides were then covalently coupled to the surface by their C-terminus using a st andard nucleophilic substitution reaction. The covalent attachment of the oligopeptides to the FEP surface was verified using electron spect roscopy for chemical analysis (ESCA). Receptor-mediated NG108-15 cell attachment on the YIGSR-modified films was determined using competitiv e binding assays. Average cell attachment on the oligopeptide immobili zed films in medium containing soluble CDPGYIGSR was reduced by approx imately a factor of 2, compared to cell attachment in serum-free mediu m alone. No significant decrease in cell attachment was noted in mediu m containing the mock oligopeptide sequence CDPGYIGSK. FEP films immob ilized with the 19-mer IKVAV sequence demonstrated a higher percentage of receptor mediated cell attachment on the film surfaces. A sixfold decrease in PC12 cell attachment occurred on the oligopeptide immobili zed films in a competitive binding assay medium containing the soluble IKVAV oligopeptide compared to cell attachment in serum-free medium a lone. These results demonstrate that laminin oligopeptides can be cova lently immobilized on an FEP material surface and analytically verifie d, and can mediate the receptor specific coupling of neuronal cells on to its surface. (C) 1995 John Wiley & Sons, Inc.