Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
J Control Release. 2011 Oct 10;155(1):47-53. doi: 10.1016/j.jconrel.2011.01.025. Epub 2011 Jan 31.
Hyaluronic acid (HA), a natural anionic mucopolysaccharide, was used to coat polyethylenimine-poly(γ-benzyl L-glutamate)/DNA (PEI-PBLG/DNA) complexes. HA was further modified by introducing RGD peptide with grafting density of one RGD in every 1.9 HA repeating units. HA can coat the cationic surface of PEI-PBLG/DNA complexes without destroying them even at high weight ratio of HA/PEI-PBLG/DNA=40/10/1. Coating the complexes by HA and HA-RGD caused lower surface charges and little bigger size than the naked PEI-PBLG/DNA. HA/PEI-PBLG/DNA has little lower transfection efficiency compared with naked PEI-PBLG/DNA, while the transfection efficiency of HA-RGD/PEI-PBLG/DNA is 9.7 times of HA/PEI-PBLG/DNA for the RGD target bonding affinity to the receptors on the cell surface. HA coating on PEI-PBLG/DNA reduced the electrostatic binding affinity to the cells while the RGD binding affinity for integrin on HeLa cells can not only compensate the reduced binding affinity but also enhance the affinity for HA-RGD/PEI-PBLG/DNA. RGD and RDG competition assay and lactate dehydrogenase (LDH) release studies further confirmed the specific target functions of RGD on HA. Cell viability measurements confirmed the high viability (above 70% viability) of the cells treated with HA-RGD and HA coated complex particles. These results would show that HA-RGD coated PEI-PBLG/DNA complexes have an attractive feature to a targeting in vivo non-viral gene delivery system.
透明质酸（HA）是一种天然阴离子粘多糖，被用于包裹聚乙基亚胺-聚（γ-苄基 L-谷氨酸）/DNA（PEI-PBLG/DNA）复合物。通过引入每个 HA 重复单元中接枝密度为 1 的 RGD 肽，进一步修饰了 HA。HA 可以包裹在阳离子表面的 PEI-PBLG/DNA 复合物上，即使在高重量比的 HA/PEI-PBLG/DNA=40/10/1 时也不会破坏复合物。HA 和 HA-RGD 包裹复合物后，表面电荷降低，粒径略有增大，与裸露的 PEI-PBLG/DNA 相比。与裸露的 PEI-PBLG/DNA 相比，HA/PEI-PBLG/DNA 的转染效率略有降低，而 HA-RGD/PEI-PBLG/DNA 的转染效率是 HA/PEI-PBLG/DNA 的 9.7 倍，这是由于 RGD 与细胞表面受体的靶向结合亲和力。HA 包裹在 PEI-PBLG/DNA 上降低了与细胞的静电结合亲和力，而 RGD 与 HeLa 细胞整合素的结合亲和力不仅可以补偿结合亲和力的降低，还可以增强 HA-RGD/PEI-PBLG/DNA 的亲和力。RGD 和 RDG 竞争实验和乳酸脱氢酶（LDH）释放研究进一步证实了 HA 上 RGD 的特异性靶向功能。细胞活力测量证实了用 HA-RGD 和 HA 包裹的复合物颗粒处理的细胞具有高活力（活力超过 70%）。这些结果表明，HA-RGD 包裹的 PEI-PBLG/DNA 复合物具有作为体内靶向非病毒基因传递系统的吸引力。
