Dutta Debjit, Kam Lance C
Department of Biomedical Engineering, Columbia University, New York, New York, USA.
Methods Cell Biol. 2014;120:53-67. doi: 10.1016/B978-0-12-417136-7.00004-5.
Lipid bilayer membranes are a central structural feature of living cells, providing a wide range of functions including partitioning of organelles, mediating cell interaction with the environment, and modulating intracellular signaling processes. By capturing the fluidity of the natural membranes in a reductionist in vitro model, substrate supported lipid bilayers have emerged as a compelling model system for these structures. Furthermore, the ability to control the composition and mobility of this system at micro- and nanoscales inspired several new routes of biological and biotechnological investigation. Here, we describe key methods used to create multicomponent lipid bilayers, discuss design considerations important to making these systems, and demonstrate this process in the specific context of understanding juxtacrine cell signaling. Different fabrication techniques were combined to first pattern a surface with barriers to lipid diffusion and then spatially control the exposure of this surface to lipid vesicles, leading to local formation of bilayers of different composition. This multicomponent system was used as a platform for to mimic the natural organization of T cells and antigen presenting cells by presenting ligands to the T cell receptor and lymphocyte function-associated antigen-1 that are tethered to separate, closely juxtaposed regions of bilayer. Other technologies like using photochemical polymerization of lipids to pattern bilayers have also been discussed. The information gathered from evaluating membrane interactions in patterned lipid bilayers may lead to the development of membrane-based biomedical devices for conducting novel cell-based assays and potentially high-throughput drug screens targeting membranes or membrane-associated components.
脂质双分子层膜是活细胞的核心结构特征，具有多种功能，包括细胞器的分隔、介导细胞与环境的相互作用以及调节细胞内信号传导过程。通过在简化的体外模型中捕捉天然膜的流动性，底物支撑的脂质双分子层已成为这些结构极具吸引力的模型系统。此外，在微米和纳米尺度上控制该系统的组成和流动性的能力激发了生物和生物技术研究的几条新途径。在这里，我们描述了用于创建多组分脂质双分子层的关键方法，讨论了构建这些系统的重要设计考虑因素，并在理解旁分泌细胞信号传导的特定背景下展示了这一过程。结合不同的制造技术，首先用脂质扩散屏障对表面进行图案化，然后在空间上控制该表面与脂质囊泡的接触，从而导致不同组成的双分子层的局部形成。这个多组分系统被用作一个平台，通过将与T细胞受体和淋巴细胞功能相关抗原-1相连的配体呈递给T细胞，这些配体被拴在双分子层的不同、紧密相邻的区域，从而模拟T细胞和抗原呈递细胞的自然组织。还讨论了其他技术，如利用脂质的光化学聚合对双分子层进行图案化。从评估图案化脂质双分子层中的膜相互作用收集到的信息可能会导致基于膜的生物医学装置的开发，用于进行新型细胞检测以及潜在的针对膜或膜相关成分的高通量药物筛选。
