Du Zixiu, Munye Mustafa M, Tagalakis Aristides D, Manunta Maria D I, Hart Stephen L
Experimental and Personalised Medicines Section, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK.
Sci Rep. 2014 Nov 19;4:7107. doi: 10.1038/srep07107.
Multifunctional, lipopolyplex formulations comprising a mixture of cationic liposomes and cationic, receptor-targeting peptides have potential use in gene therapy applications. Lipopolyplex formulations described here are typically far more efficient transfection agents than binary lipoplex or polyplex formulations. It has been shown previously that the peptide component mediates both DNA packaging and targeting of the nanoparticle while in this report we investigate the contribution of the lipid component. We hypothesised that the lipid components synergise with the peptides in the transfection process by promoting endosomal escape after lipid bilayer fusion. Lipopolyplexes were prepared with cationic liposomes comprising DOTAP with either neutral lipid DOPE or DOPC. DOPE promotes fusogenic, inverted hexagonal lipid structures while DOPC promotes more stable laminar structures. Lipopolyplexes containing DOPE showed substantially higher transfection efficiency than those formulated with DOPC, both in vitro and in vivo. DOPE-containing lipopolyplexes showed rapid endosomal trafficking and nuclear accumulation of DNA while DOPC-containing formulations remained within the late endo-lysosomal compartments. These findings are consistent with previous finding for the role of DOPE in lipoplexes and support the hypothesis regarding the function of the lipid components in lipopolyplexes. These findings will help to inform future lipopolyplex design, strategies and clinical development processes.
包含阳离子脂质体和阳离子靶向受体肽混合物的多功能脂质多聚体配方在基因治疗应用中具有潜在用途。此处描述的脂质多聚体配方通常比二元脂质体或多聚体配方更高效地作为转染剂。先前已表明肽成分介导纳米颗粒的DNA包装和靶向，而在本报告中我们研究脂质成分的作用。我们假设脂质成分在转染过程中通过促进脂质双层融合后的内体逃逸与肽协同作用。用包含DOTAP与中性脂质DOPE或DOPC的阳离子脂质体制备脂质多聚体。DOPE促进融合性、反相六角形脂质结构，而DOPC促进更稳定的层状结构。含DOPE的脂质多聚体在体外和体内均显示出比用DOPC配制的脂质多聚体显著更高的转染效率。含DOPE的脂质多聚体显示出DNA的快速内体运输和核积累，而含DOPC的配方则保留在晚期内溶酶体区室中。这些发现与先前关于DOPE在脂质体中的作用的发现一致，并支持关于脂质多聚体中脂质成分功能的假设。这些发现将有助于为未来脂质多聚体的设计、策略和临床开发过程提供信息。
