Plasmid delivery in vivo from porous tissue-engineering scaffolds:: Transgene expression and cellular Transfection
Plasmid delivery in vivo from porous tissue-engineering scaffolds:: Transgene expression and cellular Transfection
复制标题
DOI：
10.1016/j.ymthe.2005.03.036
复制
发表时间：
2005-09-01
影响因子：
12.4
通讯作者：
Shea, LD
中科院分区：
文献类型：
--
作者：
Jang, JH;Rives, CB;Shea, LD
能够持续释放质粒的组织工程支架能够促进基因的局部转移和刺激新组织的形成。我们研究了影响转基因表达程度和持续时间的支架设计参数，并描述了转染细胞的分布。以聚乳酸-羟基乙酸酯为原料，用气体发泡法制备了包封质粒的多孔支架，在发泡前用湿造粒将各组分均匀混合。与标准程序相比，湿造粒增强了质粒掺入，也增强了体内转基因表达，可能是通过增加负载和维持支架孔隙结构。质粒的负载调节了转基因的表达量和表达时间，最高表达量可达105天。表达定位于植入部位，但转染细胞的分布随时间而变化。转染的细胞最初在支架周围观察（第3天），然后在孔隙和聚合物附近观察（第17天），最后在整个支架内部观察（第126天）。与对照组相比，传递编码VEGF的质粒增加了血管密度。将支架设计与基因转移效率和组织形成相关联，将有助于质粒释放支架在多种组织中的应用。
Tissue engineering scaffolds capable of sustained plasmid release can promote gene transfer locally and stimulate new tissue formation. We have investigated the scaffold design parameters that influence the extent and duration of transgene expression and have characterized the distribution of transfected cells. Porous scaffolds with encapsulated plasmid were fabricated from poly(lactide-co-glycolide) with a gas foaming procedure, with wet granulation employed to mix the components homogeneously prior to foaming. Wet granulation enhanced plasmid incorporation relative to standard procedures and also enhanced in vivo transgene expression, possibly through the increased loading and maintenance of the scaffold pore structure. The plasmid loading regulated the quantity and duration of transgene expression, with expression for 105 days achieved at the highest dosage. Expression was localized to the implantation site, though the distribution of transfected cells varied with time. Transfected cells were initially observed at the scaffold periphery (day 3), then within the pores and adjacent to the polymer (day 17), and finally throughout the scaffold interior (day 126). Delivery of a plasmid encoding VEGF increased the blood vessel density relative to control. Correlating scaffold design with gene transfer efficiency and tissue formation will facilitate application of plasmid-releasing scaffolds to multiple tissues.