Department of Bioscience and Biotechnology, University of Camerino, Via Gentile III da Varano, 62032 Camerino (MC), Italy.
Langmuir. 2010 Sep 7;26(17):13867-73. doi: 10.1021/la1023899.
The first interaction between lipoplexes and cells is charge-mediated and not specific. Endocytosis is considered to be the main pathway for lipoplex entry. Upon interaction between lipoplexes and the plasma membrane, intermixing between lipoplex and membrane lipids is necessary for efficient endocytosis. Here we study the mechanism of the different endocytic pathways in lipid-mediated gene delivery. We show that DC-Chol-DOPE/DNA lipoplexes preferentially use a raft-mediated endocytosis, while DOTAP-DOPC/DNA systems are mainly internalized by not specific fluid phase macropinocitosys. On the other hand, most efficient multicomponent lipoplexes, incorporating different lipid species in their lipid bilayer, can use multiple endocytic pathways to enter cells. Our data demonstrate that efficiency of endocytosis is regulated by shape coupling between lipoplex and membrane lipids. We suggest that such a shape-dependent coupling regulates efficient formation of endocytic vesicles thus determining the success of internalization. Our results suggest that tailoring the lipoplex lipid composition to the patchwork-like plasma membrane profile could be a successful machinery of coordinating the endocytic pathway activities and the subsequent intracellular processing.
脂质体与细胞的最初相互作用是通过电荷介导的，而不是特异性的。内吞作用被认为是脂质体进入的主要途径。在脂质体与质膜相互作用后，脂质体与膜脂质之间的混合对于有效的内吞作用是必要的。在这里，我们研究了脂质介导的基因传递中不同内吞途径的机制。我们表明，DC-Chol-DOPE/DNA 脂质体优先使用筏介导的内吞作用，而 DOTAP-DOPC/DNA 系统主要通过非特异性的液体大胞饮作用被内化。另一方面，包含其脂质双层中不同脂质种类的最有效的多组分脂质体可以通过多种内吞途径进入细胞。我们的数据表明，内吞作用的效率受脂质体与膜脂质之间的形状耦合调节。我们提出，这种形状依赖性耦合调节有效形成内吞小泡，从而决定内化的成功。我们的结果表明，根据斑块状质膜轮廓来调整脂质体的脂质组成可能是协调内吞途径活性和随后的细胞内处理的成功机制。
