We develop a model the dynamics of human mesenchymal stem cells (hMSCs) and chondrocytes evolving in a nonwoven polyethylene terephtalate (PET) scaffold impregnated with hyaluron and supplied with a differentiation medium. The scaffold and the cells are assumed to be contained in a bioreactor with fluid perfusion. The differentiation of hMSCs into chondrocytes favors the production of extracellular matrix (ECM) and is influenced by fluid stress. The model takes deformations of ECM and PET scaffold into account. The scaffold structure is explicitly included by statistical assessment of the fibre distribution from CT images. The effective macroscopic equations are obtained by appropriate upscaling from dynamics on lower (microscopic and mesoscopic) scales and feature in the motility terms an explicit cell diffusion tensor encoding the assessed anisotropic scaffold structure. Numerical simulations show its influence on the overall cell and tissue dynamics.

翻译：我们建立了一个描述人间充质干细胞和软骨细胞在非织造聚对苯二甲酸乙二醇酯支架中演化动力学的模型，该支架浸渍了透明质酸并添加了分化培养基。假设支架与细胞均置于流体灌注型生物反应器中。hMSCs向软骨细胞的分化有利于细胞外基质的生成，并受流体应力影响。该模型考虑了ECM与PET支架的变形行为，通过CT图像纤维分布的统计学评估显式表征支架结构。采用适当的多尺度升尺度方法，从更低层次（微观及介观尺度）的动力学推导出有效宏观方程，其迁移项中包含了编码所评估各向异性支架结构的显式细胞扩散张量。数值模拟揭示了该张量对整体细胞及组织动力学过程的影响。