Rezania A, Healy K E
Division of Biological Materials, Northwestern University, 311 E. Chicago Avenue, Chicago, Illinois 60611-3008, USA.
J Biomed Mater Res. 2000 Dec 15;52(4):595-600. doi: 10.1002/1097-4636(20001215)52:4<595::aid-jbm3>3.0.co;2-3.
The density of Arg-Gly-Asp-containing peptides covalently grafted to solid materials has been shown to affect adhesion, spreading, and focal contact formation. The objective of this study was to examine the effect of ligand density on mineralization of the extracellular matrix deposited by osteoblasts. In particular, RGD-modified quartz surfaces with ligand densities varying over two orders (0.01-3.6 pmol/cm(2)) of magnitude were prepared to assess the long-term function of osteoblasts on peptide-derivatized surfaces. After 3 weeks in culture, surfaces modified with a 15 amino acid peptide (Ac-Cys-Gly-Gly-Asn-Gly-Glu-Pro-Arg-Gly-Asp-Thr-Tyr-Arg-Ala-Tyr-NH(2) ) at a density > or =0.62 pmol/cm(2) significantly (p<0.05) enhanced mineralization compared with a RGD surface density of 0.01 pmol/cm(2), RGE surfaces, or clean surfaces adsorbed with serum proteins. These results suggest that regulation of the surface density of adhesive ligands on biomaterial surfaces is a critical determinant in a strategy to alter the degree of extracellular matrix maturation in contact with solid surfaces (e.g., implants). Further studies are required to elucidate the intracellular signal transduction pathways that mediate long-term matrix mineralization through the initial engagement of these adhesive ligands.
已证明共价接枝到固体材料上的含精氨酸 - 甘氨酸 - 天冬氨酸的肽的密度会影响细胞粘附、铺展和粘着斑形成。本研究的目的是研究配体密度对成骨细胞沉积的细胞外基质矿化的影响。具体而言，制备了配体密度在两个数量级（0.01 - 3.6 pmol/cm²）范围内变化的RGD修饰石英表面，以评估成骨细胞在肽衍生化表面上的长期功能。培养3周后，与RGD表面密度为0.01 pmol/cm²的表面、RGE表面或吸附有血清蛋白的清洁表面相比，用密度≥0.62 pmol/cm²的15个氨基酸的肽（Ac-Cys-Gly-Gly-Asn-Gly-Glu-Pro-Arg-Gly-Asp-Thr-Tyr-Arg-Ala-Tyr-NH₂）修饰的表面显著（p<0.05）增强了矿化作用。这些结果表明，调节生物材料表面上粘附配体的表面密度是改变与固体表面（如植入物）接触的细胞外基质成熟程度策略中的关键决定因素。需要进一步研究以阐明通过这些粘附配体的初始结合介导长期基质矿化的细胞内信号转导途径。
