Biomedical Studies and Cellular Imaging via Atomic Force Microscopy

我们继续开发现有的生物原子力（Bio-AFM）平台、石英晶体微平衡-耗散（QCM-D）、超分辨率光学显微镜和相关测量系统，并将这些生物物理技术应用于许多生物医学和生物学研究与NIH校内和校外研究人员合作。 取得显著成果的主要合作包括： (A)我们与大卫纳鲁姆博士（NIAID，NIH），帕特里克达菲博士（NIAID，NIH）和疟疾免疫学和疫苗学实验室的其他合作研究人员合作，通过生物原子力显微镜和相关的生物分析研究了许多疟疾候选疫苗的大分子结构和纳米机械特性。这些用于疟疾疫苗的蛋白质抗原正在通过重组蛋白质生物技术生产、纯化，并以适合人体试验和大规模生产的方式进行表征。我们专注于使用AFM和QCM-D来了解正在开发的疫苗产品的结构特性，包括Qbeta病毒样颗粒作为开发疟疾疫苗载体以增强免疫反应，并正在准备出版物的手稿。 (B)我们与Ralph Nossal博士（NICHD，NIH），Eileen Lafer教授（德克萨斯大学健康科学中心，圣安东尼奥）和其他人合作，继续进行网格蛋白和网格蛋白包被囊泡（CCV）的生物原子力显微镜研究。在亚细胞运输过程中，网格蛋白Trifenia通过与衔接蛋白、膜脂质和其他辅因子的相互作用形成CCV的外部网格蛋白晶格笼。网格蛋白介导的动态大分子构建体的复杂性激发了许多结构和功能研究，包括该合作的几篇出版物。 我们已经使用了系统的QCM-D测量，以提高网格蛋白，CCV和其他组装结构的纳米机械表征的准确性。一份新的手稿即将提交。 (C)我们已经推进了一些新的校内合作，涉及生物原子力显微镜和相关的纳米技术。 两个新的合作产生了最近的出版物：（1）与Ashwin Bhirde博士（LOMIN，NIBIB），Xiaoyuan Chen博士（LOMIN，NIBIB）和其他碳纳米管和活细胞的共同研究者，以及（2）与Katelyn Nagy女士（CBL，MDP，NCI），Joel Schneider博士（CBL，MDP，NCI）和新一类蛋白质生物聚合物水凝胶的同事。 这些新的努力以及正在进行的旧合作即将取得更多成果。

We continue to develop our existing biological atomic force (Bio-AFM) platforms, Quartz Crystal Microbalance-Dissipation (QCM-D), super-resolution optical microscopy, and related measurement systems, and to apply these biophysical technologies to a number of biomedical and biological investigations in collaboration with NIH intramural and extramural researchers. Major collaborations with notable results include: (A) We have investigated the macromolecular structure and nanomechanical properties of many malaria vaccine candidates via Bio-AFM and related bioanalysis in collaboration with Dr. David Narum (NIAID, NIH), Dr. Patrick Duffy (NIAID, NIH) and other co-investigators at the Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH. These protein antigens for malaria vaccine are being produced via recombinant-protein biotechnology, purified, and characterized in a manner suitable for human trials and scale-up productions. We have focused on using AFM and QCM-D to understand the structural properties of the developing vaccine products, including Qbeta virus-like particles as developing malaria vaccine carriers for enhanced immunological response, and are preparing manuscripts for publications. (B) We have continued our Bio-AFM studies of clathrin and clathrin coated vesicles (CCVs) in collaboration with Dr. Ralph Nossal (NICHD, NIH), Prof. Eileen Lafer (Univ. Texas Health Sciences Center, San Antonio), and others. Clathrin triskelia form the outer clathrin lattice cages of the CCVs during subcellular trafficking via interactions with adaptor proteins, membrane lipids, and other cofactors. The intricacies of the clathrin-mediated dynamic macromolecular constructs have inspired numerous structural and functional studies, including several publications from this collaboration. We have used systematic QCM-D measurements to enhance the accuracy of the nanomechnical characterization for clathrin, CCVs, and other assembled structures. A new manuscript is nearing submission. (C) We have advanced a number of new intramural collaborations involving Bio-AFM and related nanotechnologies. Two new collaborations have yielded recent publications: (1) with Dr. Ashwin Bhirde (LOMIN, NIBIB), Dr. Xiaoyuan Chen (LOMIN, NIBIB) and other co-investigators on carbon nanotubes and live cells, and (2) with Ms. Katelyn Nagy (CBL, MDP, NCI), Dr. Joel Schneider (CBL, MDP, NCI) and coworkers on a new class of protein biopolymer hydrogels. More results from such new efforts, as well as ongoing older collaborations, are forthcoming.