Department of Oral and Maxillofacial Surgery, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Bavaria, Germany.
Biomaterials. 2011 Oct;32(28):6850-9. doi: 10.1016/j.biomaterials.2011.05.071. Epub 2011 Jul 8.
Bioactive implants are promising tools in regenerative medicine. Here we describe a versatile procedure for preparing a gene-activated matrix on titanium. Lyophilized copolymer-protected gene vectors (COPROGs) suspended in poly(d,l-lactide) (PDLLA) solutions in ethyl acetate were used to varnish solid surfaces. The gene-activated PDLLA surfaces were first established on polypropylene 96-well plates. Vector release from these surfaces in aqueous buffer, cell viability and gene transfer efficiency to NIH 3T3 fibroblasts was strongly dependent on the vector dose and its ratio to PDLLA film thickness. A detailed analysis of these relationships allowed establishing correlations which can be used to calculate suitable combinations of COPROGs and PDLLA yielding optimal gene transfer efficiency. This was verified with COPROG-activated PDLLA coatings on titanium foils. HEK 293 and mesenchymal stem cells expressed the BMP-2 gene comprised in the gene-activated surface in a manner that was consistent with the predicted dose-response and toxicity profiles found in NIH 3T3 cells. The systematic procedure presented here for identifying optimal coating compositions can be applied to any combination of vector type and coating material.
生物活性植入物是再生医学中很有前途的工具。在这里，我们描述了一种在钛上制备基因激活基质的多功能方法。冻干的共聚物保护基因载体（COPROGs）悬浮在乙酸乙酯中的聚（D，L-丙交酯）（PDLLA）溶液中，用于涂覆固体表面。基因激活的 PDLLA 表面首先在聚丙烯 96 孔板上建立。在水性缓冲液中从这些表面释放载体，细胞活力和基因转移效率到 NIH 3T3 成纤维细胞强烈依赖于载体剂量及其与 PDLLA 薄膜厚度的比例。对这些关系的详细分析允许建立相关性，可用于计算 COPROG 和 PDLLA 的合适组合，从而获得最佳的基因转移效率。这通过钛箔上的 COPROG 激活的 PDLLA 涂层得到了验证。HEK 293 和间充质干细胞以与在 NIH 3T3 细胞中发现的预测剂量反应和毒性谱一致的方式表达包含在基因激活表面中的 BMP-2 基因。这里提出的用于确定最佳涂层组成的系统方法可应用于任何载体类型和涂层材料的组合。
