Collective Motion in Vascular Endothelium

Collective cellular motion is a phenomenon wherein cells coordinate their movements via intra- and inter-cellular interactions. While collective motion is common in nature, occurring in systems such as insect colonies, birds, fishes, etc, the presence of cell-cell adhesion and proliferation sets collective cell behavior apart. Consequently, researchers have paid significant attention to this field, conducting in vitro studies and developing in silico models to better understand this multicellular phenomenon. Of these models, Vertex and SPV (Self-Propelled Voronoi) models have been particularly successful as they account for several physical aspects like contraction, adhesion, and changes in cell geometries and topology in confluent monolayers. In addition to cellular processes, the external physical constraints on cells also influence their motion. For example, migrating sheets of vascular endothelial cells in vivo experience directional cues from underlying extracellular matrices. Related in vitro investigations have shown that unconfined endothelial cell layers exhibit a unique form of collective motion, with cells moving in antiparallel streams when cultured on anisotropic micro-grooved substrates. In this presentation, we examine this emergent behavior through a SPV model which not only reproduces experimental findings but also provides deeper insights into how this form of collective motion manifests within cells under different physical and physiological conditions.