Static and dynamic properties of antibody proteins in solution - the effects of crowding and charge-tuning

抗体的有效医疗剂量需要在水溶液中的高浓度。这些溶液还可以含有其他分子，称为拥挤剂，其有助于增加最大蛋白质浓度或避免蛋白质聚集。我们建议使用小角散射，中子能谱和互补技术研究高浓度抗体水溶液的静态和动态特性。特别是，我们解决了大分子拥挤和离子诱导的电荷对有效的蛋白质-蛋白质相互作用，相行为，以及在溶液中的抗体的全球和内部动态的影响。我们还专注于在这个系统中的动态，瞬态，或静态集群阶段取决于所采用的物理参数。系统研究将涵盖抗体蛋白本身以及外部拥挤剂（如其他蛋白质（如BSA）、聚合物（如PEG）和糖（如海藻糖））的自拥挤效应。鉴于免疫球蛋白抗体蛋白的特殊三叶构象，该项目将特别以蛋白质形状在确定蛋白质溶液的静态和动态性质中的作用和重要性为指导。在解决与生物物理学和生物医学相关的问题时，我们将采用软物质物理学的实验和理论概念和方法。这些方法提供了一个独特的访问分子长度尺度和皮秒到纳秒的时间尺度的分子运动。我们提出的研究解决了有关应用蛋白质科学的重要问题，以及各向异性颗粒的解决方案中拥挤的基本机制。

The efficient medical dosage of antibodies requires high concentrations in aqueous solutions. These solutions can in addition contain other molecules, denoted crowding agents, which help to increase the maximum protein concentration or circumvent protein aggregation. We propose to study both static and dynamic properties of highly concentrated aqueous antibody solutions using small-angle scattering, neutron spectroscopy, and complementary techniques. In particular, we address the effects of macromolecular crowding and ion-induced charges on the effective protein-protein interactions, phase behavior, and global as well as internal dynamics of antibodies in solution. We also focus on the dynamic, transient, or static cluster phases in this system depending on the employed physical parameters. The systematic investigation will cover both the effect of self-crowding by the antibody proteins themselves as well as by external crowding agents such as other proteins (e.g. BSA), polymers (e.g. PEG), and sugars (e.g. trehalose). With view at the peculiar three-lobed conformation of immunoglobulin antibody proteins, the project will in particular be guided by the role and importance of the protein shape in the determination of the static and dynamic properties of the protein solutions. Whilst addressing questions related to biophysics and biomedicine, we will employ both experimental and theoretical concepts and methods from soft-matter physics. These methods provide a unique access to molecular length scales and to picosecond to nanosecond time scales of molecular motions. Our proposed study addresses important questions regarding applied protein science as well as fundamental mechanisms of crowding in solutions of anisotropic particles.