一种多细胞几何形状中细胞间张力和细胞-基质力学相互作用的混合模型。
A hybrid model of intercellular tension and cell-matrix mechanical interactions in a multicellular geometry.
机构信息
Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA.
Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA.
出版信息
Biomech Model Mechanobiol. 2020 Dec;19(6):1997-2013. doi: 10.1007/s10237-020-01321-8. Epub 2020 Mar 20.
Epithelial cells form continuous sheets of cells that exist in tensional homeostasis. Homeostasis is maintained through cell-to-cell junctions that distribute tension and balance forces between cells and their underlying matrix. Disruption of tensional homeostasis can lead to epithelial-mesenchymal transition (EMT), a transdifferentiation process in which epithelial cells adopt a mesenchymal phenotype, losing cell-cell adhesion and enhancing cellular motility. This process is critical during embryogenesis and wound healing, but is also dysregulated in many disease states. To further understand the role of intercellular tension in spatial patterning of epithelial cell monolayers, we developed a multicellular computational model of cell-cell and cell-substrate forces. This work builds on a hybrid cellular Potts model (CPM)-finite element model to evaluate cell-matrix mechanical feedback of an adherent multicellular cluster. Cellular movement is governed by thermodynamic constraints from cell volume, cell-cell and cell-matrix contacts, and durotaxis, which arises from cell-generated traction forces on a finite element substrate. Junction forces at cell-cell contacts balance these traction forces, thereby producing a mechanically stable epithelial monolayer. Simulations were compared to in vitro experiments using fluorescence-based junction force sensors in clusters of cells undergoing EMT. Results indicate that the multicellular CPM model can reproduce many aspects of EMT, including epithelial monolayer formation dynamics, changes in cell geometry, and spatial patterning of cell-cell forces in an epithelial tissue.
上皮细胞形成连续的细胞层,处于紧张的平衡状态。通过细胞间连接来维持平衡,这些连接分配张力并平衡细胞与其下基质之间的力。紧张平衡的破坏会导致上皮-间充质转化(EMT),这是上皮细胞获得间充质表型的一种转分化过程,丧失细胞间粘附并增强细胞迁移能力。这个过程在胚胎发生和伤口愈合中非常重要,但在许多疾病状态下也会失调。为了进一步了解细胞间张力在上皮细胞单层空间模式形成中的作用,我们开发了一个细胞间和细胞-基质力的多细胞计算模型。这项工作建立在混合细胞 Potts 模型(CPM)-有限元模型的基础上,用于评估附着多细胞簇的细胞-基质力学反馈。细胞运动受细胞体积、细胞-细胞和细胞-基质接触以及趋硬性的热力学限制,趋硬性是由细胞在有限元基质上产生的牵引力引起的。细胞接触处的连接力平衡这些牵引力,从而产生机械稳定的上皮单层。通过使用荧光基结力传感器在经历 EMT 的细胞簇中进行体外实验,对模拟结果进行了比较。结果表明,多细胞 CPM 模型可以再现 EMT 的许多方面,包括上皮单层形成动力学、细胞几何形状的变化以及上皮组织中细胞间力的空间模式。