Migliorini Elisa, Horn Patrick, Haraszti Tamás, Wegner Seraphine V, Hiepen Christian, Knaus Petra, Richter Ralf P, Cavalcanti-Adam Elisabetta Ada
Department of Biophysical Chemistry, Institute of Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120, Heidelberg, Germany.
Department of Cellular Biophysics, Max Planck Institute for Medical Research, Heisenbergstr. 3, D-70569, Stuttgart, Germany.
Adv Biosyst. 2017 Apr;1(4):e1600041. doi: 10.1002/adbi.201600041. Epub 2017 Mar 27.
Over the last decade, there has been a growing interest in the development of new materials to improve bone morphogenetic protein-2 (BMP-2) delivery for tissue regeneration. This study reports the development and application of model surfaces that present BMP-2 via heparan sulfate (HS), a ubiquitous component of the extracellular matrix (ECM). On these surfaces, HS is grafted by its reducing end, to mimic the natural arrangement of HS proteoglycans in the ECM. The binding of each component on these biomimetic surfaces is highly controlled, in terms of stoichiometry of molecules and BMP-2/grafted-HS affinity, as determined by surface-sensitive techniques. For comparison, this study also uses surfaces presenting immobilized BMP-2 alone. Functional validations of the surfaces are performed using a murine myoblast cell line (C2C12) and primary human mesenchymal stromal cells. In both cell types, HS-bound BMP-2 and surface-immobilized BMP-2 significantly prolong SMAD 1/5 phosphorylation, compared to BMP-2 added to the culture media. Moreover, HS-bound BMP-2 enhances p-SMAD 1/5 levels in C2C12 cells and reduces noggin antagonistic activity. Thus, grafted HS positively affects BMP-2 cellular activity. This innovative surface design, which mimics natural interactions of growth factors with ECM components, constitutes a promising candidate for future regenerative medicine applications.
在过去十年中，人们对开发新型材料以改善骨形态发生蛋白-2（BMP-2）递送用于组织再生的兴趣日益浓厚。本研究报告了通过硫酸乙酰肝素（HS）呈现BMP-2的模型表面的开发和应用，硫酸乙酰肝素是细胞外基质（ECM）中普遍存在的成分。在这些表面上，HS通过其还原端进行接枝，以模拟HS蛋白聚糖在ECM中的自然排列。通过表面敏感技术确定，这些仿生表面上各组分的结合在分子化学计量和BMP-2/接枝HS亲和力方面受到高度控制。为了进行比较，本研究还使用了仅呈现固定化BMP-2的表面。使用小鼠成肌细胞系（C2C12）和原代人骨髓间充质基质细胞对这些表面进行功能验证。在这两种细胞类型中，与添加到培养基中的BMP-2相比，HS结合的BMP-2和表面固定的BMP-2显著延长了SMAD 1/5磷酸化。此外，HS结合的BMP-2增强了C2C12细胞中的p-SMAD 1/5水平，并降低了头蛋白的拮抗活性。因此，接枝的HS对BMP-2的细胞活性有积极影响。这种模仿生长因子与ECM成分自然相互作用的创新表面设计，是未来再生医学应用的一个有前途的候选者。
