Modification of glassy carbon surfaces with synthetic laminin-derived peptides for nerve cell attachment and neurite growth

Abstract

Interactions between cultured nerve cells and surfaces are of importance for the implantation of biocompatible electrode materials such as glassy carbon (GC). Since implants serve as recording sensors in prosthetic neuroscience, we investigated whether coating electrodes with certain laminin derivatives containing the peptide sequences SIKVAV, CDPGYIGSR, PDSGR, YFQRYLI, and RNIAEIIKDA influences neuronal adhesion and neurite outgrowth in vitro. The coating of GC was performed by electrochemical polymerization and, for comparison, by adsorption or covalent coupling. Electrochemical polymerization is suitable for the coupling of peptides to GC, as shown by amino acid analysis and sequencing. Embryonic chicken retinal ganglion cells and brain cells (days E7 or E17) were used for both attachment and growth studies. Surfaces made by electrochemical polymerization of peptides were more efficient than those made by adsorption or covalent coupling of peptides. Synthetic cyclic peptide derivatives of CDPGYIGSR and 18-mer SIKVAV were found to be more efficient than the linear peptides. Competitive effects that resulted in a decreased cell attachment could be found upon application of soluble peptides. Nevertheless, irrespective of the method of coating, peptides were less efficient compared with the whole laminin molecule, as expected from its multiple adhesion sites. When small GC pins were implanted into the brain of E17 chicken after coating with the 18-mer SIKVAV peptide, nerve cell attachment was observed in vivo. The results suggest that chronically implantable materials may exert a higher neurocompatibility when coated with synthetic peptides.

In vitro assessment of bioactive coatings for neural implant applications

“…The results are in agreement with other reports in the literature. 20,21 Applications for the IKVAV peptide-grafted coating technology include developing tracts for guidance of neurite growth on implant surfaces and coating areas around recording/stimulation sites to promote neurite growth near the sites for optimal signal transfer between neurons and implants.…”

“…For surface coatings with neurite growth-promoting activity, the laminin-based peptide SRARKQAASIKVAVSADR (Bachem) was utilized. Studies by Thanos et al 20,21 showed that this peptide is very effective in promoting neurite growth in vitro.…”

Biology on a Chip: Microfabrication for Studying the Behavior of Cultured Cells

“…Since then many studies in neuronal patterning have been performed in a variety of labs, using various methods, including surface modification by silane chemistry 113 137 Ti, 140 polystyrene, 130,131 Teflon (fluorinated ethylene propylene), [132][133][134][141][142][143][144] and biodegradable polymers. 145 These studies mainly yielded insights into the adhesion and guidance of neuronal growth by insoluble factors and could prove valuable for selective neuronal immobilization on future microsensors.…”

Peptoid-containing collagen mimetics with cell binding activity

“…These structures are constructed primarily to mimic known peptide sequences such as the RGD and YIGSR cell attachment motifs. 11,[62][63][64][65] In this study, we present a novel collagenmimetic sequence, composed of nine or ten repeats of the sequence (GPNl), that has cell binding activity through an "RGD-independent" mechanism. Although we have not studied extensively the mechanism of cell attachment to this collagen-mimetic molecule, we believe that the ␣2␤1 integrin complex is involved.…”