AI Insight
This study develops a mathematical framework linking individual cell mechanics to tissue-scale behavior using a viscous vertex model, which simulates how cells interact during biological tissue formation and shape changes. The researchers incorporated explicit viscous friction and active stress mechanisms into their model, creating mean-field rheological relations that describe how tissues respond to mechanical forces across elastic and visco-plastic regimes. They validated their approach using large-amplitude oscillatory shear tests and demonstrated that tissue rheological properties depend critically on specific model parameters.
Why it matters
Understanding how individual cell properties determine tissue-scale mechanical behavior is essential for predicting morphogenesis during development and potentially for designing tissue engineering applications. The generalizable framework presented could be applied to various cell-based tissue models, advancing our ability to predict and control tissue shape changes in both biological and biomedical contexts.
Understand the Science
arXiv:2602.22855v2 Announce Type: replace-cross
Abstract: Morphogenesis involves complex shape changes of biological tissues. Yet, tissue shape changes depend on tissue rheology, which in turn arises from the interplay of large numbers of cells. Here, we link cell- and tissue-scale mechanics by constructing mean-field rheological relations for the vertex model. In contrast to past work in the field, we study a vertex model with an explicit viscous friction. We also include two different cellular mechanisms creating active, anisotropic stresses. Our mean-field model accounts for cell shape and the non-linear elastic and visco-plastic regimes. We validate our results by predicting the response to large-amplitude oscillatory shear. There are several vertex model variants, and comparing to results from the literature, we show that their rheology depends on a number of model details. Our approach should be sufficiently general to construct non-linear mean-field constitutive relations for any cell-based tissue model.
Source: Non-linear visco-elasto-plastic rheology of a viscous vertex model