Wang Chung-Hao, Hsu Yi-Shiou, Peng Ching-An
Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan.
Biosens Bioelectron. 2008 Dec 1;24(4):1018-25. doi: 10.1016/j.bios.2008.08.009. Epub 2008 Aug 13.
The increasing threats of viral diseases have gained worldwide attention in recent years. Quite a few infectious diseases are still lacking effective prevention or treatment. The pace of developing antiviral agents could be expedited by the availability of quick and efficient drug screening platforms. In this study, quantum dot (QD), an emerging probe for biological imaging and medical diagnostics, was employed to form complexes with virus and used as fluorescent imaging probes for exploring potential antiviral therapeutics. Inorganic CdSe/ZnS QDs synthesized in organic phase were encapsulated by amphiphilic alginate to attain biocompatible water-soluble QDs via phase transfer. Virus employed for this study was dengue virus which is a notorious one in tropical and subtropical regions of the world. To construct a QD-virus imaging modality capable of providing meaningful information, preservation of viral infectivity after tagging virus with QDs is of utmost importance. In order to form colloidal complexes of QD-virus, electrostatic repulsion force generated from both negatively charged virus and QDs was neutralized by various concentrations of cationic polybrene. Results showed that BHK-21 cells infected with dengue viruses incorporated with QDs exhibited bright fluorescence intracellularly within 30 min. To demonstrate the potency of QD-virus complexes as bioprobes for screening antiviral agents, BHK-21 cells were incubated for one hour with allophycocyanin purified from blue-green algae and then infected with QD-virus complexes. Based on the developed cell-based imaging assay, allophycocyanin with concentration of 125 microg/mL led to extremely weak intracellular fluorescence post-infection of QD-virus complexes for 30 min. That is, the efficacy of anti-dengue viral activity of the algae extract was clearly illustrated by the inorganic-organic hybrid platform constructed in current study.
近年来，病毒性疾病日益增加的威胁已引起全球关注。相当多的传染病仍缺乏有效的预防或治疗方法。快速高效的药物筛选平台的出现可以加快抗病毒药物的研发速度。在本研究中，量子点（QD）作为一种新兴的生物成像和医学诊断探针，与病毒形成复合物，并用作荧光成像探针来探索潜在的抗病毒疗法。通过相转移，用两亲性藻酸盐包裹在有机相中合成的无机CdSe/ZnS量子点，以获得具有生物相容性的水溶性量子点。本研究使用的病毒是登革热病毒，它在世界热带和亚热带地区臭名昭著。为了构建能够提供有意义信息的量子点-病毒成像模式，在用量子点标记病毒后保持病毒感染性至关重要。为了形成量子点-病毒的胶体复合物，通过不同浓度的阳离子多聚赖氨酸中和带负电荷的病毒和量子点产生的静电排斥力。结果表明，感染了与量子点结合的登革热病毒的BHK-21细胞在30分钟内细胞内呈现明亮荧光。为了证明量子点-病毒复合物作为筛选抗病毒药物的生物探针的效力，将从蓝藻中纯化的别藻蓝蛋白与BHK-21细胞孵育1小时，然后用量子点-病毒复合物感染。基于所开发的基于细胞的成像分析，浓度为125μg/mL的别藻蓝蛋白在量子点-病毒复合物感染30分钟后导致细胞内荧光极弱。也就是说，本研究构建的无机-有机杂化平台清楚地说明了藻类提取物抗登革热病毒活性的功效。
