Porous tantalum coated with RGD polypeptide can activate the integrin/focal adhesion kinase signaling pathway of MG63 cells / 中国组织工程研究

ABSTRACT

BACKGROUND: The compounding of RGD polypeptide on the surface of the material can induce the expression of osteoblast integrin gene, promote the adhesion of osteoblasts to the surface of biomaterials and differentiate into mature cells, and promote the formation of new bone. OBJECTIVE: To analyze the effect of domestic porous tantalum modified by RGD polypeptide on integrin/focal adhesion kinase signaling pathway in MG63 cells. METHODS: Porous tantalum material modified by RGD polypeptide was prepared. MG63 cells were inoculated on the surface of porous tantalum and porous tantalum materials modified with RGD polypeptide. MG63 cells cultured alone were used as the blank group. When cultured for 1, 3, 5, and 7 days, the cell proliferation was detected by the CCK-8 method. At 1, 3, and 5 days, the cell growth status was observed under an inverted microscope. At 3, 5 days of culture, cell adhesion was observed with scanning electron microscope. At 5 days of culture, RT-PCR and western blot assay were used to detect type I collagen and integrin β1 and focal adhesion kinase expression. RESULTS AND CONCLUSION: (1) The cell proliferation of the RGD modified group cultured at 3, 5, and 7 days was faster than that of the porous tantalum group and the blank group (P 0.05). (2) Observation by an inverted phase contrast microscope showed that the cells of the porous tantalum group and the RGD modified group were attached to the edge of the material when cultured for 1 day, and the number of cells gradually increased with the extension of the culture time. The number and density of cells in the RGD modified group were better than that of the porous tantalum group. (3) Observation by scanning electron microscope showed that cells adhered to the surface of the porous tantalum group and RGD modified group after 3 days of culture. The cells adhered to the material pore walls and pores, and protruded pseudopods into the pores. When cultured for 5 days, the cells secreted a large amount of extracellular matrix, and the cells were connected to each other through the matrix and gradually covered the surface of the material. The cell growth state, matrix secretion and cell coverage area of the RGD modified group were better than those of the porous tantalum group. (4) Western blot detection results showed that the expressions of type I collagen and integrin β1 protein in the RGD modified group were higher than those in the porous tantalum group and the blank group (P < 0.05). The expression levels of type I collagen, integrin β1, and focal adhesion kinase protein in the porous tantalum group were higher than those in the blank group (P < 0.05). (5) RT-PCR detection showed that the expressions of type I collagen, integrin β1, and focal adhesion kinase mRNA in the RGD modified group were higher than those of the porous tantalum group and the blank group (P < 0.05), and the expression of the porous tantalum group was higher than that of the blank group (P < 0.05). (6) The results showed that porous tantalum modified with RGD polypeptide can up-regulate the expression of type I collagen and integrin β1 on the cell membrane, activate the integrin/focal adhesion kinase signaling pathway, and promote cell adhesion and growth.