颗粒-蛋白相互作用分子机制及代谢重编程敏感的循环肿瘤细胞捕获方法研究

纳米颗粒-蛋白相互作用及其对生物学效应的影响研究非常重要且不断深入。但蛋白冠参与的纳米颗粒与肿瘤细胞静电粘附作用的研究却鲜有报道。申请人研究发现因瓦伯格效应，肿瘤细胞糖酵解代谢乳酸导致的细胞膜负电荷可作为广谱性、全细胞亚类的循环肿瘤细胞纳米捕获的标志物；FBS蛋白吸附使正电荷颗粒表面电位翻转为较强负电，却仍然保留了原始正、负电颗粒对肿瘤细胞的静电粘附行为的显著差异，其中机制尚不清楚，也未见报道；且蛋白参与可保护痕量细胞活性。因此，本项目聚焦蛋白分子二级结构变化造成的带电结构域排布及对原始颗粒电荷性质的影响，及蛋白参与的颗粒-细胞膜静电作用的分子机制和调控方法研究；考察颗粒亲疏水、粗糙度、电荷特性对FBS\BSA\HSA\Fibrinogen吸附行为影响，运用LC-MS、QCM-D、CD等方法表征蛋白特性，揭示颗粒-蛋白复合物与肿瘤细胞膜的静电粘附规律，并建立模型预测构-效关系显著性。

The study on mechanism of nanoparticle - protein interaction and its effect on biological effects is very pivotal and experiencing fast progress, but the research of electrostatic adhesion between nanoparticles and tumor cell membrane involved in protein corona is rarely reported. In previous research, the applicant found that the negative charge of cell membrane caused by glycolysis and metabolism of lactic acid of tumor cells can be used as a marker for capture of circulating tumor cells (CTCs) with wide spectrum and covering more whole cell subgroups due to “Warburg Effect”. FBS proteins exhibited overwhelming effect of maintenance of rare cells viability than PBS. Formation of protein corona can significantly change the original Zeta potential characteristics of particles and promote the efficient and stable capture of rare cells, but its molecular mechanism and tuning method need to be studied. In this project, it is planned to reveal the influence of magnetic nanoparticles with different characteristics of hydrophobicity, roughness and surface charge on the secondary structure variety and orientation distribution of charged amino acid residues of the adsorbed protein molecules. Based on this, this project focuses on the study of molecular mechanism that the molecular structure variety and charged amino acid residues and domain of the adsorbed protein molecules are affected by the physicochemical properties of the original nanoparticles, and the regulation of the electrostatic interaction between the nanoparticles and tumor cells membrane in which the protein corona participates. To investigate the influence of particle characteristics of hydrophobicity, roughness and surface charges on the adsorption behavior of FBS \ BSA \ HSA \ fibrinogen, several analytical approaches including LC-MS, QCM-D, CD and other methods are applied to characterize the protein characteristics. QSAR stimulation model was used to analyze the significance of multiple factors influencing the biological end point. This study is expected to provide the theoretical basis for the application of new tumor liquid biopsy.