kT-scale Protein & Carbohydrate Interactions on Synthetic Materials & Cell Surfaces

PI：Bevan，Michael A.提案编号：1402739机构：约翰霍普金斯大学题目：合成材料细胞表面上的kT级蛋白质碳水化合物相互作用许多重要的细胞相互作用涉及“弱”相互作用，这很难用目前的技术来表征。PI建议进入新的领域，通过使用PI小组开发的扩散胶体探针显微镜（DCPM）技术直接表征生物分子的这些弱分子间相互作用。该提案将研究两个系统的生物学的重要性，这也是他们的意义，选择生物医学问题：干细胞为基础的组织工程和癌症转移。弱生物相互作用研究技术的成功发展将对理解细胞-细胞粘附、细胞迁移、组织形态发生、转移、免疫学和其他细胞过程中的这种相互作用产生影响。弱生物分子相互作用（kT量级）在细胞-细胞粘附、细胞迁移、组织形态发生、转移、免疫学和其他细胞过程中起重要作用。虽然有测量强相互作用（pN力）的标准机械方法，但弱相互作用通常通过光谱方法间接测量。PI建议通过使用DCPM直接表征这些相互作用来进入新的领域，DCPM提供了使用扫描探针或光谱方法无法获得的空间和时间分辨率，统计意义和直接性。本质上，DCPM被动地监测“扩散探针”的布朗偏移，并在询问蛋白质和碳水化合物的相互作用时利用这些自然的时间（a2/D）、能量（kT）、力（fN）和长度（nm）计量器。这本质上是一种纳米级技术，因为它利用布朗运动作为一种有用的工具来直接测量蛋白质之间的kT相互作用，而不是避免随机热运动作为纳米级系统的不希望的复杂性。将研究两个系统，CD 44-HA相互作用和异嗜性钙粘蛋白相互作用（在钙离子存在下）支持的双层。DCPM用于研究弱生物相互作用的发展将对理解细胞-细胞粘附、细胞迁移、组织形态发生、转移、免疫学和其他细胞过程中的这种相互作用产生影响。

PI: Bevan, Michael A. Proposal Number: 1402739Institution: Johns Hopkins University Title: kT-scale Protein & Carbohydrate Interactions on Synthetic Materials & Cell Surfaces Many important cellular interactions involve "weak" interactions, which are difficult to characterize by current techniques. The PI proposes to move into new territory, in terms of directly characterizing these weak intermolecular interactions of biomolecules, by using a technique, Diffusing Colloidal Probe Microscopy (DCPM), developed by the PI's group. The proposal will examine two systems of biological importance, which were also chosen for their significance to biomedical problems: stem-cell based tissue engineering and cancer metastasis. Success in the development of the technique for studying weak biological interactions will have an impact on the understanding of such interactions in cell-cell adhesion, cell migration, tissue morphogenesis, metastasis, immunology, and other cellular processes.Weak biomolecular interactions, on the order of kT, play an important role in cell-cell adhesion, cell migration, tissue morphogenesis, metastasis, immunology, and other cellular processes. While there are standard mechanical methods for measuring strong interactions (pN forces), weak interactions are generally measured_ indirectly_ by spectroscopic means. The PI proposes to move into new territory, by directly characterizing these interactions using DCPM, which offers spatial and temporal resolution, statistical significance, and directness not accessible using scanning probes or spectroscopic methods. In essence, DCPM passively monitors Brownian excursions of "diffusing probes" and exploits these natural gauges for time (a2/D), energy (kT), force (fN), and length (nm) when interrogating the interaction of proteins and carbohydrates. This is inherently a nanoscale technique because it harnesses Brownian motion as a useful tool to directly measure kT interactions between proteins rather than avoiding stochastic thermal motion as an undesirable complication of nanoscale systems. Two systems will be studied, CD44-HA interactions and heterophilic cadherin interactions (in the presence of calcium ions) on supported bilayers. The development of DCPM for studying weak biological interactions will have an impact on the understanding of such interactions in cell-cell adhesion, cell migration, tissue morphogenesis, metastasis, immunology, and other cellular processes.