Enhancing the neuronal interaction on fluoropolymer surfaces with mixed peptides or spacer group linkers

Embryonic hippocampal neurons cultured on surface modified fluoropolymers s howed enhanced interaction and neurite extension. Poly(tetrafluoroethylene- co-hexafluoropropylene) (FEP) film surfaces were aminated by reaction with a UV-activated mercury ammonia system yielding FEP-[N/O]. Laminin-derived c ell-adhesive peptides (YIGSR and IKVAV) were coupled to FEP surface functio nal groups using tresyl chloride activation. Embryonic (E18) hippocampal ne urons were cultured in serum-free medium for up to 1 week on FEP film sur f aces that were modified with either one or both of GYIGSR and SIKVAV or GGG GGGYIGSR and compared to control surfaces of FEP-[N/O] and poly(L-lysine)/l aminin-coated tissue culture polystyrene. Neuron-surface interactions were analyzed over time in terms of neurite outgrowth (number and length of neur ites), cell adhesion and viability. Neurite outgrowth and adhesion were sig nificantly better on peptide-modified surfaces than on either FEP or FEP-[N /O]. Cells on the mixed peptide (GYIGSR/SIKVAV) and the spacer group peptid e (GGGGGCYIGSR) surfaces demonstrated similar behavior to those on the posi tive PLL/laminin control. The specificity of the cell-peptide interaction w as demonstrated with a competitive assay where dissociated neurons were inc ubated in media containing peptides prior to plating. Cell adhesion and neu rite outgrowth diminished on all surfaces when hippocampal neurons were pre -incubated with dissolved peptides prior to plating. (C) 2001 Elsevier Scie nce Ltd. All rights reserved.