Design and activity of multifunctional fibrils using receptor-specific small peptides.

We have designed multifunctional peptide fibrils using bioactive laminin-derived peptides and evaluated their potential as a biomedical material for tissue engineering. The Leu-Arg-Gly-Asp-Asn (LRGDN) peptide derived from laminin-111, which contains an RGD sequence bound to integrin alphavbeta3, was added to the N-terminus of the four amyloidogenic cell-adhesive laminin-derived peptides (A119: LSNIDYILIKAS, AG97: SAKVDAIGLEIV, B133: DISTKYFQMSLE, and B160: VILQQSAADIAR). The RGD-conjugated peptides were stained with Congo red and exhibited amyloid-like fibril formation in the electron microscopic. The RGD-conjugated peptides promoted human dermal fibroblasts spreading with well-organized actin stress fibers and focal contacts. Human dermal fibroblast attachment to the RGD-conjugated peptides was inhibited by anti-alphav integrin antibody. Further, cell attachment to B133 was inhibited by anti-alpha2 and anti-beta1 integrin antibodies, whereas attachment to RGD-B133 was inhibited by anti-alphav and anti-beta1 integrin antibodies. These results suggest that the RGD-conjugated peptides interact with integrin alphavbeta3 and that RGD-B133 interacts with both integrin alphavbeta3 and integrin beta1. The RGD-conjugated peptide fibrils promoted neurite outgrowth in a peptide-dependent manner. These results support that biologically active sequence-conjugated peptide fibrils interact in a receptor-specific manner with cells and promote multifunctional activities. These fibrils may have use as biological supports for cell-specific tissue engineering.