Kashiwagi Kenji, Tsuji Toru, Shiba Kiyotaka
Department of Protein Engineering, Cancer Institute, Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo 135-8550, Japan.
Biomaterials. 2009 Feb;30(6):1166-75. doi: 10.1016/j.biomaterials.2008.10.040. Epub 2008 Nov 20.
Efficient immobilization of biomacromolecules on material surfaces is a key to development in areas of regenerative medicine and tissue engineering. However, strong and irreversible immobilization of cytokines on surfaces often diminishes their biological functionality. A destructive hydrophobic interaction between the material surface and the biomolecule may underlie this inactivation. Alternatively, dissociation of the cytokine from the material may be necessary for signal transduction. Here we propose a new method for immobilizing cytokines on material surfaces: a material-binding artificial peptide is used to mediate reversible interaction between the cytokine and the material surface. We created artificial proteins that contained three copies of a Ti-binding motif, and fused them to the N-terminal of BMP-2. The engineered BMP-2 showed reversible binding to Ti surfaces and induced BMP signaling activity. When a hydrophobic protein devoid of the Ti-binding motif was fused to BMP-2, the protein tightly bound to Ti surfaces but showed little BMP activity, confirming the importance of the mode of immobilization.
生物大分子在材料表面的高效固定是再生医学和组织工程领域发展的关键。然而，细胞因子在表面的强烈且不可逆固定往往会降低其生物学功能。材料表面与生物分子之间具有破坏性的疏水相互作用可能是这种失活的原因。或者，细胞因子从材料上解离可能是信号转导所必需的。在此，我们提出一种将细胞因子固定在材料表面的新方法：使用一种与材料结合的人工肽介导细胞因子与材料表面之间的可逆相互作用。我们创建了包含三个钛结合基序拷贝的人工蛋白，并将它们融合到BMP - 2的N端。工程化的BMP - 2显示出与钛表面的可逆结合并诱导BMP信号活性。当将缺乏钛结合基序的疏水蛋白融合到BMP - 2上时，该蛋白紧密结合到钛表面，但几乎没有BMP活性，这证实了固定方式的重要性。
