Magneto-nanosensor platform for probing low-affinity protein-protein interactions and identification of a low-affinity PD-L1/PD-L2 interaction.
Magneto-nanosensor platform for probing low-affinity protein-protein interactions and identification of a low-affinity PD-L1/PD-L2 interaction.
复制标题
用于探测低亲和力蛋白 - 蛋白质相互作用的磁纳米传感器平台以及低亲和力PD-L1/PD-L2相互作用的鉴定。
DOI：
10.1038/ncomms12220
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发表时间：
2016-07-22
影响因子：
16.6
通讯作者：
Wang SX
中科院分区：
文献类型：
--
作者：
Lee JR;Bechstein DJ;Ooi CC;Patel A;Gaster RS;Ng E;Gonzalez LC;Wang SX
已经做出了大量努力来理解免疫检查点受体与其在针对癌症的免疫疗法中靶向的配体之间的相互作用。为了仔细表征所涉及的相互作用的完整网络和它们的胞外结构域之间的结合亲和力，需要改进的动力学测定来克服表面等离子体共振（SPR）的限制。在这里，我们提出了一个磁纳米传感器平台集成的微流控芯片，允许在微摩尔范围内的解离常数的测量。磁性纳米颗粒与猎物蛋白质的高密度缀合允许多价受体与传感器固定的诱饵蛋白质相互作用，更接近地模仿细胞上的天然受体簇。与传统SPR相比，该平台具有信号响应对pH和盐度不敏感、蛋白质消耗少和灵敏度高等优点。使用该平台，我们表征了PD-1-PD-L1/PD-L2共抑制受体系统的结合亲和力，并发现了两种已知PD-1配体PD-L1和PD-L2之间的意外相互作用。 低亲和力蛋白质-蛋白质相互作用的测量具有挑战性;表面等离子体共振需要高浓度的试剂。在这里，作者将联合收割机磁纳米传感器与微流控芯片和蛋白质缀合的磁性纳米颗粒相结合，发现T细胞抑制性受体PD-L1和PD-L2之间的低亲和力相互作用。
Substantial efforts have been made to understand the interactions between immune checkpoint receptors and their ligands targeted in immunotherapies against cancer. To carefully characterize the complete network of interactions involved and the binding affinities between their extracellular domains, an improved kinetic assay is needed to overcome limitations with surface plasmon resonance (SPR). Here, we present a magneto-nanosensor platform integrated with a microfluidic chip that allows measurement of dissociation constants in the micromolar-range. High-density conjugation of magnetic nanoparticles with prey proteins allows multivalent receptor interactions with sensor-immobilized bait proteins, more closely mimicking natural-receptor clustering on cells. The platform has advantages over traditional SPR in terms of insensitivity of signal responses to pH and salinity, less consumption of proteins and better sensitivities. Using this platform, we characterized the binding affinities of the PD-1—PD-L1/PD-L2 co-inhibitory receptor system, and discovered an unexpected interaction between the two known PD-1 ligands, PD-L1 and PD-L2. Measurement of low-affinity protein–protein interactions is challenging; surface plasmon resonance requires high concentrations of reagents. Here the authors combine magneto-nanosensors with microfluidic chips and protein-conjugated magnetic nanoparticles to discover a low-affinity interaction between T-cell inhibitory receptors PD-L1 and PD-L2.