Using optical tweezers to determine the binding force between dengue virus and cellular receptors

• Main Authors: Chun-Yu Chen, 陳君諭
• Other Authors: Yueh-Hsin Ping
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/53335747863505058062

碩士 === 國立陽明大學 === 生醫光電研究所 === 103 === Optical tweezers (OT) is a powerful tool used to manipulate a single particle in living cell and also used to determine the interaction force of biological molecule(s) in an excellent resolvable range from 1 to 100 pN. Dengue virus (DENV) is one of the most widespread viral pathogens around the world. Little is known about the complex and highly dynamic process of dengue infection. As a result, no antiviral drug is available for treating DENV diseases and no vaccine available yet. Therefore, a new antiviral target for DENV is imperative. Among DENV infectious process, receptor-binding is the first critical step contributes for successful infection. Elucidation of the receptor-binding details is helpful for exploring dengue pathology. In this study, we used OT to determine the interaction force between DENV and different host cellular receptor(s). We have analyzed the single virus binding forces 20.6± 16.0 pN and 34.2± 10.0 pN to differentiated THP-1 and CHO cells respectively. After that, we increased virus density bound on PS beads to increase the number of DENV particle interaction with cellular receptors at the same time. The results revealed that both forces and interaction probabilities in above two cell lines were increased. Furthermore, we transfected CHO cells with CD209 (DC-SIGN) plasmids, and measured an enhanced binding force at 62.5± 6.8 pN. Herein, we have established a system for measuring the binding forces between ideally single virus particle and host cellular receptors. We have resolved different binding forces in different cells and under either different bead modification or receptor modification. These results revealed the potential of OT to resolve different binding force between virus and cells. And provided a real-time force measured system in living cells.