Enhanced attachment and growth of periodontal cells on glycine-arginine-glycine-aspartic modified chitosan membranes

Abstract

Background: Chitosan, a polymeric carbohydrate derived from the exoskeleton of arthropod, has been suggested to be an excellent biomaterial for improving wound healing, especially for bones. To improve the periodontal cell attachment and growth, the cell adhesive peptide glycine-arginine-glycine-aspartic acid (Gly-Arg-Gly-Asp, GRGD) grafted chitosan membrane was introduced in this study. Materials and Methods: Two types of commercial chitosan, three types of primary cultured cells, and two established cell lines were used. Human gingival and periodontal fibroblasts (hGF and hPDL), human root derived cell (hRDC), and rat calvaria bone cell (rCalB) were cultured on the GRGD-fixed by ultraviolet light photochemical method on the chitosan membrane. With (3-[4,5-dimethylthiazol-2-yl]-5-[3-carboxymethoxyphenyl]-2-[4-sulfophenyl]-2H-tetrazolium) assay and propidium iodine (PI) staining, the cell adhesion and growth on GRGD-grafted chitosan were examined. Basal mRNA expressions of the receptors for GRGD, integrin αv (ITG αv) and ITG β3, in the human gingival fibroblast cell line and mouse osteoblast cell line (MC3T3-E1) were examined with real-time polymerase chain reaction. Results: Because the cell adhesion/growth patterns on two chitosan membranes were similar, the GRGD modification was performed on one membrane (Primex) only. For periodontal cells (hGFs, hPDLs, and hRDCs), the number of attached cells were increased on the membrane with the high concentration of GRGD than those on the membrane unmodified or modified with low concentration GRGD. For rCalBs cells, a different pattern was noted: GRGD modification did not enhance the calvaria cells attachment or growth. Moreover, mRNA expressions of ITG αv and β3 in AG09319 cells were significantly higher than those in MC3T3-E1 cells. Conclusions: With the limitation of this study, we suggested that GRGD-modified chitosan, especially at high concentration, could enhance the growth of various periodontal fibroblasts, but did not change those of osteoblasts. Therefore, chitosan might be an excellent biomaterial for periodontal use.