Laminin oligopeptide derivatized agarose gels allow three-dimensional neurite extension in vitro

The phenotypic expression of various neural cells is influenced by extracellular matrix (ECM) molecules. This study aims to develop a three-dimensional gel tailored to support neurite extension from neural cells. Laminin-derived (LN) oligopeptides CDP-GYIGSR, a 19-mer IKVAV containing sequence, GRGDSP, a cocktail of the three aforementioned LN peptides (PEPMIX), and a control peptide sequence GGGGG were covalently linked to an agarose hydrogel backbone using the bi-functional coupling agent 1'1, carbonyldiimidazole. Embryonic day 9 chick DRGs and PC12 cells were suspended in three dimensions in underivatized and derivatized agarose gels and neurite extension was analyzed. Agarose gels derivatized with CDPGYIGSR and PEPMIX enhanced neurite outgrowth from DRGs while GRGDSP and IKVAV derivatized gels inhibited neurite extension when compared to underivatized agarose gels. The IKVAV derivatized gels significantly enhanced neurite outgrowth from PC12 cells in comparison to underivatized and other LN peptide derivatized gels. Agarose hydrogels carrying covalently immobilized LN oligopeptides thus evoke specific responses from cells which contain receptors to the peptides used. Agarose hydrogels derivatized with neurite promoting peptide sequences may find applications in various models of in vivo regeneration of nervous tissue.