| Measurement of Protein-Protein Interactions through Microscale Thermophoresis (MST)
|
|
Author:
Date:
2020-04-05
[Abstract] The binding interactions of PD-1 and PD-L1 have been studied by surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC) over the past few years, but these investigations resulted in controversy regarding the values of the dissociation constant (Kd) (Freeman et al., 2000). MST is a powerful new method for the quantitative analysis of protein-protein interactions (PPIs) with low sample consumption. The technique is based on the movement of molecules along microscopic temperature gradients, and it detects changes in their hydration shell, charge or size. One binding partner is fluorescently labeled, while the other binding partner remains label-free. We used a protocol that allows the determination of the binding affinity by MST without purification of ...
[摘要] [摘要 ] 近年来，通过表面等离振子共振（SPR）和等温滴定热法（ITC）研究了PD-1和PD-L1的结合相互作用，但这些研究引起了解离常数值的争议。 （ķ d ）（弗里曼等人，2000） 。MST是一种功能强大的新方法，可定量分析低样品消耗的蛋白质-蛋白质相互作用（PPI）。该技术基于分子沿微观温度梯度的移动，并检测其水合壳，电荷或大小的变化。一个结合蛋白摹伴侣荧光拉贝领导， 而另一个绑定伙伴仍保持无标签状态。我们使用的协议允许通过MST确定结合亲和力，而无需从细胞裂解物中纯化靶蛋白。将此MST方法应用于在CHO-K1细胞中表达的PD-1-eGFP和PD-L1-eGFP的应用，首次使我们能够确定PD-1及其配体PD-L1之间形成的复合物的亲和力在肿瘤逃逸期间。该协议在研究蛋白质与小分子之间的相互作用方面具有多种潜在应用。
[背景技术 [ 0002 ] 鉴定能够调节PD-1和PD-L1之间形成的复合物的亲和力的化合物代表了针对肿瘤免疫逃逸的新疗法的开发的重大进展。该方案涉及eGFP 融合蛋白的过表达，然后从细胞裂解物中提取eGFP 融合蛋白，无需任何纯化步骤即可测定PD-1和PD-L1之间的亲和常数。因此，该协议的发展需要产生eGFP 融合蛋白。该协议旨在通过避免繁琐的纯化步骤来定量加速蛋白质相互作用的表征。该协议还可以用于通过PD-1 / ...
|
|
|
| Loading of Extracellular Vesicles with Chemically Stabilized Hydrophobic siRNAs for the Treatment of Disease in the Central Nervous System
|
|
Author:
Date:
2017-06-20
[Abstract] Efficient delivery of oligonucleotide therapeutics, i.e., siRNAs, to the central nervous system represents a significant barrier to their clinical advancement for the treatment of neurological disorders. Small, endogenous extracellular vesicles were shown to be able to transport lipids, proteins and RNA between cells, including neurons. This natural trafficking ability gives extracellular vesicles the potential to be used as delivery vehicles for oligonucleotides, i.e., siRNAs. However, robust and scalable methods for loading of extracellular vesicles with oligonucleotide cargo are lacking. We describe a detailed protocol for the loading of hydrophobically modified siRNAs into extracellular vesicles upon simple co-incubation. We detail methods of the workflow from ...
[摘要] 将寡核苷酸治疗剂即siRNAs有效递送到中枢神经系统代表了治疗神经系统疾病的临床进展的显着障碍。 小的内源性细胞外囊泡显示能够在细胞（包括神经元）之间传输脂质，蛋白质和RNA。 这种天然的贩运能力使细胞外囊泡成为寡核苷酸即siRNA的递送载体的潜力。 然而，缺乏用寡核苷酸载体装载细胞外囊泡的稳健和可扩展的方法。 我们描述了在简单共孵育后将疏水修饰的siRNA加载到细胞外囊泡中的详细方案。 我们详细介绍了从细胞外囊泡纯化到数据分析的工作流程。 该方法可以促进基于细胞外基于囊泡的疗法用于治疗广泛的神经障碍。
【背景】siRNA是一种类型的寡核苷酸治疗剂，一类新的直接靶向信使RNA（mRNA）的药物，以防止导致疾病表型的蛋白质的表达。 siRNA的治疗应用是非常有希望的，因为siRNA可以被设计为靶向任何基因，包括不能用小分子或基于蛋白质的疗法“可药用”的基因。在寡核苷酸治疗剂的化学中取得的进展使得能够设计完全稳定的疏水改性的siRNA（hsiRNA，用2'-O-甲基或2'-氟以及硫代磷酸酯和共价键合到胆固醇的有义链修饰），其促进细胞hsiRNA的自我内化，并保持有效负载在RNA诱导的沉默复合体（RISC）中的能力（Byrne等，2013; Khvorova和Watts，2017）。与乘客链的3'末端连接的胆固醇缀合物对于快速细胞膜缔合是必需的（Byrne等，2013; ...
|
|
|
| Isolation of Phagosomes from Dendritic Cells by Using Magnetic Beads
|
|
Author:
Date:
2013-07-20
[Abstract] Phagosomes are intracellular organelles in dendritic cells in which pathogens such as viruses, bacteria and parasites are internalised to be proteolysed and killed. Phagosomes are formed by fusion with the plasma membrane, some area of the endoplasmic reticulum as well as the lysosome. This protocol described the purification of phagosomal compartments at different stage of their maturation using magnetic beads.
[摘要] 吞噬体是树突细胞中的细胞内细胞器，其中病原体例如病毒，细菌和寄生虫被内化以被蛋白水解和杀死。 吞噬体通过与质膜，内质网的一些区域以及溶酶体融合形成。 该协议描述了使用磁珠在其成熟的不同阶段的吞噬体隔室的纯化。
|
|
|