Bagno Andrea, Piovan Alessandro, Dettin Monica, Brun Paola, Gambaretto Roberta, Palù Giorgio, Di Bello Carlo, Castagliuolo Ignazio
Department of Chemical Process Engineering, University of Padova, via Marzolo 9, 35131, Padova, Italy.
Bone. 2007 Oct;41(4):704-12. doi: 10.1016/j.bone.2007.06.008. Epub 2007 Jun 22.
Investigations on the relationships between the properties of biomaterial surfaces and cell adhesion/proliferation processes have recently gained increasing interest. To describe the behaviour of cells adhering and proliferating over different types of (and/or differently treated) substrates, some mathematical models have been also suggested in literature; these models consider both the dependence of cell adhesion/proliferation over time, and the influence of substrate morphology in allowing (or even hampering) cell attachment. Major developments in the biochemical functionalization of the materials used for the production of endosseous devices have been achieved; the ability of the so-called "biomimetic" surfaces to promote cell adhesion, thus favoring the osseointegration process, is already well acknowledged. The aim of this study was to formulate a mathematical model for osteoblast adhesion, mediated by an adhesion peptide (sequence 351-359 mapped on the Human Vitronectin Protein) covalently grafted to a titanium-based surface. To assure a highly homogenous orientation of the peptide to cells, the "specific functionalization" strategy was properly designed. Enzymatic detachment assays allowed comparing osteoblast behaviour over three differently treated titanium substrates (i.e., oxidized, silanized, and peptide-grafted), thus determining how and how much the bioactive peptide can improve the strength of cell adhesion. The results confirmed the capacity of the peptide to increase cell adhesion and adhesion strength; moreover, the role of the peptide was described by a mathematical equation characterizing cells behaviour.
近年来，关于生物材料表面特性与细胞黏附/增殖过程之间关系的研究越来越受到关注。为了描述细胞在不同类型（和/或不同处理）的基质上黏附与增殖的行为，文献中也提出了一些数学模型；这些模型既考虑了细胞黏附/增殖随时间的依赖性，也考虑了基质形态对细胞附着的促进（或阻碍）作用。用于制造骨内装置的材料在生化功能化方面取得了重大进展；所谓“仿生”表面促进细胞黏附从而有利于骨整合过程的能力已得到充分认可。本研究的目的是建立一个数学模型，用于描述由共价接枝到钛基表面的黏附肽（映射在人玻连蛋白上的序列351 - 359）介导的成骨细胞黏附。为确保肽对细胞具有高度均匀的取向，对“特异性功能化”策略进行了合理设计。酶解脱离试验能够比较成骨细胞在三种不同处理的钛基质（即氧化、硅烷化和肽接枝）上的行为，从而确定生物活性肽如何以及在多大程度上能够提高细胞黏附强度。结果证实了该肽增加细胞黏附及黏附强度的能力；此外，通过描述细胞行为的数学方程阐述了该肽的作用。
