Viscoelasticity of multicellular systems caused by collective cell migration depends on (1) viscoelasticity of migrating clusters, (2) viscoelasticity of surrounding resting cells and (3) the size, slip effects and thickness of the biointerface. A previously developed model for a sharp biointerface is expanded for the case of a finite biointerface based on thermodynamic and rheological considerations to estimate the influence of the biointerface properties on viscoelasticity. These properties of the interface layer are one of the key factors which influence the overall properties of the mixture, such as its viscoelasticity. Sliding of cell clusters through dense surroundings induces generation of significant shear stress, within the biointerface, which influences (1) the active (contractile) or passive state of single cells and (2) the state of cell-cell adhesion contacts. Cells retain collectivity in migration patterns even upon a reduction of cell-cell adhesion caused by stress generation. A greater size to the biointerface leads to the weakening of multicellular systems for the same volume fraction of migrating cells due to energy dissipation. Various factors such as (1) increase of the interface size, (2) reduction in slip effects under the constant thickness of the biointerface and (3) decrease in the biointerface thickness under constant slip effects induce an increase of the shear rate as well as the overall energy dissipation and can lead to circular cell movement within the biointerface layer. Additional experiments at subcellular and cellular levels are needed to determine the influence of mechanical factors on collective cell migration.

中文翻译：

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由集体细胞迁移引起的多细胞系统的粘弹性：生物界面的动力学。

由集体细胞迁移引起的多细胞系统的粘弹性取决于（1）迁移簇的粘弹性，（2）周围静止细胞的粘弹性以及（3）生物界面的大小，滑移效应和厚度。基于热力学和流变学的考虑，针对有限生物界面的情况扩展了先前开发的用于尖锐生物界面的模型，以估计生物界面特性对粘弹性的影响。界面层的这些性质是影响混合物的整体性质（例如其粘弹性）的关键因素之一。穿过密集环境的细胞簇滑动会在生物界面内诱导产生明显的剪切应力，这会影响（1）单细胞的主动（收缩）或被动状态，以及（2）细胞与细胞间粘附接触的状态。即使在应力产生引起的细胞间粘附减少的情况下，细胞仍保持迁移模式中的集体性。对于相同体积分数的迁移细胞，由于能量耗散，生物界面的较大尺寸导致多细胞系统的弱化。各种因素，例如（1）界面尺寸的增加，（2）在生物界面厚度不变的情况下滑移效应的减小和（3）在恒定滑动效应下的生物界面厚度的减小会导致剪切速率的增加以及整个能量耗散，并可能导致生物界面层内的圆形细胞运动。