National Engineering Research Center for Biomaterials, Sichuan University, Chengdu 610064, China.
Biomaterials. 2012 Jun;33(19):4917-27. doi: 10.1016/j.biomaterials.2012.03.030. Epub 2012 Apr 7.
The quest for highly efficient and safe gene delivery systems has become the key factor for successful application of gene therapy. Peptide dendrimers are currently investigated as excellent candidates for non-viral gene delivery vectors. In this study, we report the synthesis and characterization of arginine functionalized peptide dendrimer-based vectors ranging from 5th generation (G5A) to 6th generation (G6A) via click chemistry, and their use for gene transfection in vitro and in vivo. The dendrimers can condense plasmid DNA (pDNA) and protect pDNAs from nuclease digestion. Both atomic force microscopy (AFM) and dynamic light scattering (DLS) revealed that the sizes of dendrimer/DNA particles were within 180-250 nm range. In vitro studies showed that the functionalized peptide dendrimers provided serum independent and high transfection efficiency on all studied cells, as over 2 fold higher than that of branched polyetherimide (PEI) in the presence of serum. Dendrimer G5A with molecular weight of 17 kDa demonstrated 6-fold transfection activity than PEI in breast tumor models, as well as good biosafety proved by in vitro and in vivo toxicity evaluation. However, G6A with molecular weight of 46 kDa showed much higher cytotoxicity. The functionalized dendrimer G5A with optimal generation may be therefore a potential candidate for gene delivery vehicle.
寻找高效、安全的基因传递系统已成为基因治疗成功应用的关键因素。肽树状大分子目前被认为是一种很有前途的非病毒基因传递载体。在这项研究中，我们通过点击化学法合成并表征了第 5 代（G5A）至第 6 代（G6A）的精氨酸功能化肽树状大分子载体，并将其用于体外和体内的基因转染。树状大分子可以使质粒 DNA（pDNA）凝聚，并保护 pDNA 免受核酸酶的消化。原子力显微镜（AFM）和动态光散射（DLS）均表明，树状大分子/DNA 颗粒的大小在 180-250nm 范围内。体外研究表明，功能化的肽树状大分子在有血清和无血清的情况下均能提供独立于血清的高效转染效率，在有血清的情况下，其转染效率比支化聚醚酰亚胺（PEI）高 2 倍以上。分子量为 17kDa 的树状大分子 G5A 在乳腺癌模型中的转染活性比 PEI 高 6 倍，并且通过体外和体内毒性评估证明具有良好的生物安全性。然而，分子量为 46kDa 的 G6A 显示出更高的细胞毒性。因此，具有最佳代数的功能化树状大分子 G5A 可能是一种有前途的基因传递载体候选物。
