Biomimetic approach on human periodontal ligament cells using synthetic oligopeptides

Background: Periodontal ligament (PDL) cells, connecting root cementum with alveolar bone, are important for periodontal wound healing. In order to obtain a predictable periodontal regeneration, selective adhesion and proliferation of PDL cells are essential. The purpose of this study was to investigate the effects of synthetic peptides mimicking cell-binding domain of fibronectin (FN) on human PDL cells. Methods: Two types of oligopeptides, Gly(3)-Pro-His-Ser-ArgAsn-Gly(6)-Arg-Gly-Asp-Gly (G(3)PHSRNG(6)RGDG) and Gly(3)-His-Pro-Asn-Arg-Ser-Gly(6)-Arg-Gly-Asp-Gly (G(3)HPNRSG(6)RGDG), were constructed using a solid-phase peptide synthesizer. Fibronectin type III ninth to tenth domain (FN III 9-10) and Arg-Gly-Asp-Ser (RGDS) were prepared for comparison with the effects of synthetic peptides. These peptides were coated onto 96-well cell culture plates with 0.001 similar to 100 muM concentrations. Cultured human PDL cells were then applied to the peptide-coated wells at a density of 1 x 10(4)/well. After 1 hour incubation at 37degreesC, adhered cells were fixed, stained, and examined by phase contrast microscopy for cell spreading assay. Attached PDL cells were solubilized with 2% sodium dodecyl sulfate (SDS) for the cell attachment assay by measuring absorbance at 595 nm in microplate reader. Western blot analysis was performed to determine extracellular signal-regulated kinase (ERK1/2) activity. Results: Cell attachment and spreading assays revealed that G(3)PHSRNG(6)RGDG ( greater than or equal to10 muM) possesses similar adhesive behavior to FN III 9-10. G(3)PHSRNG(6)RGDG showed a comparable ERK1/2 activity when compared to FN III 9-10. Conclusions: G(3)PHSRNG(6)RGDG enhanced an attachment and spreading of human PDL cells thereby increasing ERK1/2 activity. Taken together, it is anticipated that this peptide might be a potential tool for arranging a biologically attractive environment for PDL cells, which would enhance periodontal regeneration efficacy.