Intermittent migration of a cell cluster in a confluent tissue

During early mouse embryogenesis a group of cells, the distal visceral endoderm (DVE), move through intermittent bursts of motion. Motivated by this we model the dynamics of a self-propelled (active) cell cluster within a background of passive cells in a vertex model of confluent tissue. For small strengths of self-propulsion, the cluster comes to a halt, whereas for large strengths of self-propulsion, the cluster migrates steadily within the tissue. Interestingly, for intermediate strengths of self-propulsion, we find that the yield-stress rheology of the surrounding passive cells results in a regime of intermittent motion of the migrating cluster.