Collaborative Research: Multiscale Modeling and Experimental Study of Blood Cell Interactions with Application to Functionalized Leukocytes Killing Cancer Cells

超过90%的癌症相关死亡是由癌症转移引起的，即癌症的扩散。 在许多情况下，癌细胞从原发性肿瘤逃逸并进入脉管系统以形成循环肿瘤细胞（CTC）。血管内的CTC能够粘附于血管壁，然后迁移到组织中，最终形成微转移。最近，人们发现，当在其表面上涂覆有某些类型的配体和受体的纳米颗粒被注射到血液中时，这些颗粒可以与CTC结合，随后引发血液中CTC的死亡。该项目涉及使用集成的数学/计算建模和实验来定量了解这种结合过程是如何发生的，并确定配体-受体结合和细胞-细胞相互作用在此过程中发挥的作用。该项目的结果将有助于设计用于治疗癌症转移的新纳米粒子医疗过程，并广泛扩展血细胞动力学的知识。这些结果在生物工程和医学领域的许多应用中具有实际意义。该研究还将为学生提供跨学科的培训。通过结合建模，模拟和实验，该项目解决了一个重要的生物学问题，以了解癌症转移。什么是有助于提高涂层纳米颗粒触发血管系统内循环癌细胞死亡的效率的关键因素？ 将为这项研究开发新的三维多尺度模型。在这种情况下，一个新的子模型代表细胞膜力学，流体-结构相互作用模拟方法和随机配体-受体键结合/解结合子模型将开发和耦合。原子力显微镜和微流控实验在三个空间尺度将被设计用于模型验证和验证模拟预测。将校准的多尺度模拟与实验相结合的变革策略将能够测试某些脂质体涂层杀死流动肿瘤细胞的新假设机制。这些目标将通过使用迭代过程来实现，该过程涉及开发子模型，运行实验以验证子模型，然后运行预测模拟并设计新的实验以验证这些预测。

More than 90% of cancer-related deaths are caused by cancer metastasis, the spread of a cancer. In many cases, cancer cells escape from the primary tumor and enter vasculature to form circulating tumor cells (CTCs). CTCs inside blood vessels are able to adhere to vessel walls, and then migrate into tissues, eventually forming micro-metastases. Recently, it was found that when nano-particles coated with certain types of ligands and receptors on their surfaces were injected into the blood, these particles can bind to CTCs and subsequently trigger death of CTCs in the blood. The project concerns using integrated mathematical/computational modeling and experiments to understand quantitatively how this binding process occurs and to identify the roles that ligand-receptor binding and cell-cell interactions play during this process. Results from the project will shed light on designing new nano-particle medical processes for the treatment of cancer metastasis and broadly extend the knowledge of blood cell dynamics. The results are of practical importance in many applications in both bio-engineering and medical communities. The research will also provide interdisciplinary training for students.By combining modeling, simulation and experiments, this project addresses a key biological question of importance to understanding cancer metastasis. What are the key factors that contribute to improving the efficiency of coated nano particles for triggering the death of circulating cancer cells within the vascular system? New three-dimensional multi-scale models will be developed for this study. In this context, a novel sub-model representing cell membrane mechanics, a fluid-structure interaction simulation method and a stochastic ligand-receptor bond bind/unbinding sub-model will be developed and coupled. Atomic force microscopy and micro-fluidic experiments at three spatial scales will be designed for model validation and verifying simulation predictions. The transformative strategy of coupling calibrated multi-scale simulations with experiments will enable testing of novel hypothesized mechanisms by which certain coatings of liposomes kill flowing tumor cells. These goals will be achieved by using an iterative procedure involving development of sub-models, running experiments to validate the sub-models, and then running predictive simulations and designing new experiments for verification of these predictions.