Physical models for collective cell migration
Doctor of Philosophy
Collective cell migration is crucial for many physiological processes in both development and repair of multicellular organisms, such as embryonic development, wound healing, and metastasis formation. These processes often involve complex mechanical and biochemical interactions between cells and their environment, making the underlying mechanisms very hard to understand. For example, the role of the actomyosin cable during a wound healing, the origin of fingering protrusions at the leading front of an epithelial sheet etc. have been debated for a long time. Yet, despite many experimental observations, a unified theory remains to be developed. Here, we provide an advanced particle-based model that includes purse-string contraction, leader cells and other biophysical properties of Madin-Darby canine kidney (MDCK) cells to study these complex processes. This model not only captures the details of the dynamics especially the traction force patterns and velocity profiles in many different systems but also predicts new phenomena such as an intermediate phenotype between the leader and the followers in fingering protrusions. In parallel, we develop an active fluid model to analyze the interface stability, which provides a fundamental physics view for this phenomenon. In summary, this work provides a general framework to study different phenomena and their mechanisms in collective cell migration and it could serve as a guide for related experimental works.
Physical models; Collective cell migration; Active matter; Tissue