Instituto de Engenharia Biomédica, Divisão de Biomateriais, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal.
Nanomedicine (Lond). 2011 Nov;6(9):1499-512. doi: 10.2217/nnm.11.51. Epub 2011 Oct 20.
To study the mechanism of transfection mediated by imidazole-grafted chitosan (CHimi) nanoparticles, to propose new strategies to control and improve the expression of a delivered gene in the context of regenerative medicine.
Biochemical and microscopy methods were used to establish transfection efficiency and nanoparticle intracellular trafficking. The role of CHimi and degree of N-acetylation (DA) on transfection was explored.
CHimi was found to promote the expression of a delivered gene during a minimum 7-day period. Additionally, the production of a protein of interest could be upheld by consecutive transfections, without compromising cell viability. Transfection was found to be a time-dependent process, requiring CHimi-DNA complex disassembling. The DA was found to have an impact on transfection kinetics in line with the observation that the rate of lysozyme-mediated nanoparticle degradation increases with the polymer DA.
The adjustment of the CH degradation rate can be used as a tool for tuning the expression of a gene delivered by CH-based nanoparticle systems.
研究咪唑接枝壳聚糖（CHimi）纳米粒介导转染的机制，提出控制和改善再生医学中递送达基因表达的新策略。
采用生化和显微镜方法确定转染效率和纳米颗粒的细胞内转运。探讨 CHimi 和 N-乙酰化程度（DA）在转染中的作用。
CHimi 被发现可在至少 7 天的时间内促进递达基因的表达。此外，通过连续转染可以维持感兴趣蛋白的产生，而不影响细胞活力。转染是一个时间依赖的过程，需要 CHimi-DNA 复合物的解组装。DA 对转染动力学有影响，与观察到的溶菌酶介导的纳米颗粒降解速率随聚合物 DA 增加而增加的结果一致。
调整 CH 的降解速率可作为调节基于 CH 的纳米颗粒系统递达基因表达的工具。
