Department of Biomedical Engineering, University of California, Davis, California 95616, USA.
J Biomed Mater Res A. 2010 Aug;94(2):344-54. doi: 10.1002/jbm.a.32690.
Current strategies to enhance gene transfer have focused on the development of vectors to increase the efficiency of DNA delivery. However, the extracellular matrix and microenvironment have a profound impact on numerous cellular activities including spreading and proliferation; two processes that have been associated with gene transfer efficiency. This study was designed to test the hypothesis that the presence of a biomineralized coating on biodegradable substrates would affect transgene expression following nonviral gene delivery. Thin films were prepared from polymeric microspheres, while biomineralized films were fabricated from microspheres previously soaked in modified simulated body fluid. Mineralized films were significantly more rigid and had widespread mineral coverage compared with nonmineralized substrates. Human mesenchymal stem cells (MSCs) were cultured on biomineralized or nonmineralized films and transfected with plasmid DNA condensed with linear polyethyleneimine (PEI). Compared with cells transfected on nonmineralized films, increases in gene expression were detected in the presence of biomineral at all charge ratios examined. We observed increased uptake of both PEI and DNA by cells on mineralized films. The results of these studies offer an approach to modulate gene delivery and improve the potential benefit of nonviral gene delivery approaches.
目前增强基因转移的策略集中于开发载体以提高 DNA 递送的效率。然而，细胞外基质和微环境对许多细胞活动有深远的影响，包括细胞的扩展和增殖；这两个过程与基因转移效率相关。本研究旨在检验以下假设：生物矿化涂层的存在会影响非病毒基因递送后的转基因表达。通过聚合微球制备薄膜，而通过先前在改良的模拟体液中浸泡的微球制备生物矿化薄膜。与非矿化基底相比，矿化薄膜具有更高的刚性和更广泛的矿物覆盖。将人骨髓间充质干细胞（MSCs）培养在生物矿化或非矿化薄膜上，并与线性聚乙烯亚胺（PEI）凝聚的质粒 DNA 转染。与转染非矿化薄膜上的细胞相比，在所有检测的电荷比下，在存在生物矿化的情况下都检测到基因表达的增加。我们观察到矿化薄膜上的细胞对 PEI 和 DNA 的摄取均增加。这些研究的结果提供了一种调节基因传递的方法，并提高了非病毒基因传递方法的潜在益处。
