Mechanobiology

力学生物学

• 批准号: 10919031
• 负责人: Alexander Cartagena-Rivera
• 金额: $ 143.89万
• 依托单位: NATIONAL INSTITUTE OF BIOMEDICAL IMAGING AND BIOENGINEERING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10919031
• 关键词: 3-Dimensional; Actins; Actomyosin; Anisotropy; Antibodies; Antigen-Presenting Cells; Antigens; Architecture; Atomic Force Microscopy; Behavior; Biological; Biology; Biomechanics; CD28 Antigens; CD3 Antigens; Cancer Biology; Cancer Detection; Cancer cell line; Cancerous; Cause of Death; Cell Nucleus; Cells; Cellular Structures; Cellular biology; Characteristics; Chemicals; Cochlea; Communities; Complex; Cytoskeleton; Development; Developmental Biology; Dimensions; Disease; Disease Progression; Distal; Dorsal; Elasticity; Engineering; Epithelium; Extracellular Matrix; F-Actin; Gel; Generations; Glycocalyx; Goals; Growth; Hearing; Heterogeneity; Hydrostatic Pressure; Integrins; Investigation; Knowledge; Label; Laboratories; Labyrinth; Liquid substance; Lymphocyte; Lymphocyte Activation; Maintenance; Malignant Neoplasms; Malignant neoplasm of ovary; Malignant neoplasm of pancreas; Maps; Mathematics; Measures; Mechanics; Mediator; Metastatic Malignant Neoplasm to the Ovary; Methodology; Microtubules; Modulus; Molecular; Monitor; Myosin Type II; National Institute of Biomedical Imaging and Bioengineering; Neoplasm Metastasis; Organelles; Patients; Physics; Physiological; Play; Polymers; Postbaccalaureate; Postdoctoral Fellow; Process; Prognosis; Proliferating; Property; Regulation; Research Project Grants; Role; Sampling; Sensory; Side; Site; Solid Neoplasm; Spectrum Analysis; Stress; Surface Tension; Surveys; T-Lymphocyte; Tissues; Traction; Traction Force Microscopy; Viscosity; biophysical techniques; cancer cell; cancer therapy; cantilever; cell motility; cell type; cellular development; complex biological systems; genetic regulatory protein; imaging modality; immune activation; immunological synapse; interest; materials science; mechanical force; mechanical properties; migration; minimally invasive; molecular mechanics; mortality; multidisciplinary; nanomechanics; nanoscale; neoplastic cell; non-muscle myosin; novel strategies; novel therapeutic intervention; pancreatic cancer cells; post-doctoral training; pressure; sample fixation; self organization; spatiotemporal; surface coating; tool; trait; transmission process; tumor microenvironment; tumor progression; viscoelasticity

The NIBIB's Section on Mechanobiology mainly focuses on developing advanced atomic force microscopy (AFM) approaches to determine the micro- and nano-scale mechanical properties of cells and tissues. AFM is a versatile biophysical technique where a sample is probed with a micron sized cantilever with or without an indenter to measure, in a minimally invasive way, the physical material properties of complex biological systems (from molecules to tissues) at physiologically relevant conditions. A major advantage of this experimental approach is that it does not require any chemical manipulation (neither labelling or fixation). This is the main reason why AFM is the main biophysical approach used in our lab. Project #1: Pancreatic cancer cells and solid tumor mechanics: role of cellular actomyosin cytoskeleton, glycocalyx, and microenvironment architectures promoting mechanical heterogeneity, anisotropy, and regulation. Cancer is one of the leading causes of death in the world, and currently the major concern with cancer mortality is metastasis. Cancer is a broad term applying to diseases having the common characteristic traits that can lead to abnormal cellular development with a rapid and uncontrollable burst of growth and proliferation, resulting in solid tumor formation and metastatic dissemination. Different cell types and mediators in the tumor microenvironment aid in disease progression, whereby tumor cell adaptability is key for their motility and invasiveness. Besides many abnormalities in structural architecture and composition, cellular and ECM mechanics are directly implicated in disease progression. Changes in the actomyosin cytoskeleton and glycocalyx, for example, play a critical role in metastasis of ovarian and pancreatic cancers, among others. To successfully metastasize to a distal site, cells must migrate through physical constraints, including regions of high confinement, requiring the cell body and its nucleus (the largest and stiffest organelle) to deform, generally at timescales considered slow in the nanomechanics community. Thus, understanding the ways in which the solid tumor microenvironment and cancer cell aberrations are related to changes in mechanical properties at timescales of biological relevance may reveal new therapeutic strategies to stop or at least slow down cancer progression and metastasis. My laboratory's Postdoctoral fellow Dr. Andrew Massey, performed a wide survey of the mechanical properties (actomyosin cortical tension, Young's modulus, Storage Modulus and Loss Modulus, hydrostatic intracellular pressure) of pancreatic cancer cell lines at different stages of malignancy. It should be noted that cellular cortical mechanics could be a great candidate for cancer detection, monitoring, and prognosis. We used a biophysical methodology developed during my postdoctoral training based on quasi-static AFM force spectroscopy that utilizes tipless cantilevers to determine relevant mechanical properties of single loosely adhered cells including actomyosin tension, Young's modulus, and intracellular hydrostatic pressure. Additionally, we performed high spatiotemporal nanomechanical mapping to determine the nanoscale viscoelastic properties (elastic storage and loss viscous modulus). We observed that pancreatic cancer cells show are softer and less viscous than healthy ones and that they become much softer and fluid with increased levels of malignancy. Finally, we are currently determining the nanoscale viscoelastic behavior of patient primary and live metastatic pancreatic cancer tissues. These observations are critical for establishing novel strategies for cancer treatment. Project #2: Understanding the mechanobiology of T lymphocytes. The immunological synapse formed between a T lymphocyte and its target is a physical and dynamic cellular structure capable of exerting mechanical force. Recently, it has been shown that force generation by the actin and microtubule cytoskeletons enable the formation and maintenance of the immune synapse in T lymphocytes and can vary in the presence of different antigens. However, T lymphocytes ability to promote and sustain changes in force generation within the immune synapse by modulating their mechanical properties remains unknown. My laboratory's Post-Baccalaureate fellow Mr. Kun Do is spearheading this research project. We quantified biomechanical properties on both the dorsal and basal side of activated T lymphocytes by coating the surface of well-characterized soft polymer gels with antibodies against the CD3 region of the TCR-complex, the lymphocyte integrin LFA-1, and costimulatory molecule CD28 to mimic interactions between T lymphocytes and antigen presenting cells (APCs). To do this, we combined high spatiotemporal nanomechanical AFM mapping and traction force microscopy to measure dorsal biomechanics, including surface tension and viscoelasticity, as well as basal side mechanics that present themselves through traction stresses at the immune synapse. We are also currently exploring the role of key filamentous actin cytoskeletal regulatory proteins known to play an important role in immune cell activation and in the formation and maintenance of the immune synapse, including non-muscle myosin II, formin, and septins.

Nibib关于机械生物学的部分主要集中于开发先进的原子力显微镜（AFM）方法，以确定细胞和组织的微观和纳米级机械性能。 AFM是一种多功能的生物物理技术，其中样品是用微米大小的悬臂探测的，有或没有缩进器，以微创的方式测量，是在生理相关条件下复杂生物系统（从分子到组织）的复杂生物系统（从分子到组织）的物理物质特性。这种实验方法的主要优点是它不需要任何化学操作（既不标记或固定）。这是AFM是我们实验室中使用的主要生物物理方法的主要原因。 项目＃1：胰腺癌细胞和实体瘤力学：细胞肌动蛋白细胞骨架，糖蛋白果胶和微环境体系结构促进机械异质性，各向异性和调节的作用。癌症是世界上死亡的主要原因之一，目前，癌症死亡率的主要关注点是转移。癌症是一个广泛的术语，适用于具有常见特征性状的疾病，可能导致异常的细胞发育，并迅速且无法控制的生长和增殖，从而导致实体瘤形成和转移性传播。肿瘤微环境中的不同细胞类型和介体有助于疾病进展，从而使肿瘤细胞的适应性是其运动和侵入性的关键。除了结构结构和组成的许多异常外，细胞和ECM力学还直接与疾病进展有关。例如，肌动蛋白细胞骨架和糖蛋白的变化在卵巢和胰腺癌的转移中起着至关重要的作用。要成功地转移到远端位点，细胞必须通过物理约束迁移，包括高约束的区域，需要细胞体及其核（最大，最僵硬的细胞器）才能变形，通常在纳米力学社区中被认为慢的时间表处。因此，了解实体瘤微环境和癌细胞像差与生物学相关性时间尺度上的机械性能变化有关的方式可能会揭示出新的治疗策略，以停止或至少减缓癌症的进展和转移。 我实验室的博士后研究员安德鲁·梅西（Andrew Massey）博士对机械性能进行了广泛的调查（肌动蛋白皮质张力，Young的模量，储存模量和损失模量，静水压模量，细胞内压）的胰腺癌细胞系在不同的恶性阶段。应该注意的是，细胞皮质力学可能是癌症检测，监测和预后的好候选者。我们使用了基于准静态AFM力光谱的博士后训练期间开发的生物物理方法，该方法利用倾斜的悬臂来确定单个松散粘附细胞的相关机械性能，包括肌动肌球蛋白张力，Young的模量，Young的模量和细胞内液压压力。此外，我们进行了高时空纳米力学映射，以确定纳米级粘弹性特性（弹性存储和丢失粘性模量）。我们观察到胰腺癌细胞比健康的癌细胞表现出较软且粘稠的粘性，并且它们变得更柔软，液体较软，并且恶性肿瘤水平升高。最后，我们目前正在确定患者原发性和活胰腺癌组织的纳米级粘弹性行为。这些观察对于建立新的癌症治疗策略至关重要。 项目＃2：了解T淋巴细胞的机械生物学。 T淋巴细胞及其靶标之间形成的免疫突触是能够施加机械力的物理和动态细胞结构。最近，已经表明，肌动蛋白和微管细胞骨架的产生能够形成和维持T淋巴细胞中免疫突触的形成和维持，并且在存在不同抗原的情况下可能会变化。但是，通过调节其机械性能，T淋巴细胞能够促进和维持免疫突触中力产生和维持变化的能力。 我的实验室后的后库司同学Kun Do先生率先为这项研究项目率先。我们通过用针对TCR-复合物的CD3区域的特征良好的软聚合物凝胶的表面覆盖活化T淋巴细胞的背侧和基底侧的生物力学性能， （APC）。为此，我们结合了高时空纳米力学的AFM映射和牵引力显微镜，以测量背侧生物力学，包括表面张力和粘弹性，以及通过免疫突触处的牵引力来表现出来的基础机制。我们目前还在探索已知在免疫细胞激活以及免疫突触的形成和维持中起重要作用的关键丝状肌动蛋白细胞骨架调节蛋白的作用，包括非肌肉肌球蛋白II，folmin和septins。