Computer simulation models and visualization tools for tissue engineering

本研究的目的是开发计算机仿真模型和可视化工具，以促进组织工程师的工作。具有预测能力的计算模型将大大加快这一领域的进展。这些模型将帮助研究人员预测细胞群对外部刺激的动态反应，从而使他们能够评估各种系统参数对组织再生过程的速率以及最终生物人工结构和质量的影响。然而，组织生长的模拟是一个具有计算挑战性的问题，需要大的网格来处理离散细胞的种群，需要小的时间步长来准确地描述细胞种群动态。组织再生是当今最具挑战性的生物工程问题之一。目前治疗器官或组织衰竭的方法包括移植、手术重建或植入人工装置，这些疗法的成功率有限。另一种方法是用患者自身细胞生长的生物替代物来替代衰竭的组织或器官。生物替代品必须复制它们所取代的组织的结构。因此，它们是建立在由合适的生物材料制成的三维支架上的。除了作为结构部件外，支架还为生物人工结构提供合适的形状和三维基质，用于引导细胞迁移和增殖。支架也可用于促进伤口愈合，这是许多衰弱性疾病患者面临的一个严重问题。目前，组织替代品的开发几乎完全基于经验方法，需要许多昂贵和耗时的实验，这些实验是由生物学发现所驱动的。然而，组织是高度复杂的系统，许多因素可以影响它们的功能、结构和生长速度。这些因素的范围从生物材料和支架的特性到许多外部刺激，这些刺激以仍然知之甚少的方式调节重要的细胞功能。

The objective of this research is the development of computer simulation models and visualization tools to facilitate the work of tissue engineers.  Computational models with predictive abilities will greatly speed up progress in this area. Such models will help researchers predict the dynamic response of cell populations to external stimuli, thus enabling them to assess the effect of various system parameters on the rates of tissue regeneration processes, as well as on the structure and quality of the final bio-artificial constructs.  However, the simulation of tissue growth is a computationally challenging problem requiring large grids to handle the populations of discrete cells and small time steps to accurately describe the cell population dynamics. Tissue regeneration is one of the most challenging bioengineering problems today.  The current approach for treating organ or tissue failure includes transplantation, surgical reconstruction or implanting artificial devices, therapies that are limited in success. An alternative is to replace the failing tissue or organ with a biological substitute grown from the patient's own cells.  Biological substitutes must reproduce the architecture of the tissues they replace. For this reason, they are built on three-dimensional scaffolds made from suitable biomaterials.  Besides serving as the structural component, the scaffolds provide the proper shape of the bio-artificial construct and a three-dimensional matrix for guided cell migration and proliferation.  Scaffolds may also be used to promote wound healing, a serious problem with patients suffering from many debilitating diseases.  Currently, the development of tissue substitutes is almost exclusively based on empirical approaches that require many expensive and time-consuming experiments motivated by biological discoveries.  However, tissues are highly complex systems and a multitude of factors can influence their function, structure and growth rates.  These factors range from properties of biomaterials and scaffolds to the numerous external stimuli that modulate important cellular functions in ways that are still poorly understood.