A recent study, with Sunkel at the helm, has revealed enlightening new information. It exposes the complicated ways that growth can actually restrict movement within cell communities. The Max Planck Institute for Dynamics and Self-Organization (MPI-DS) had led this research. It emphasizes the difficulty that colonies of cells face when they grow and divide, in particular with respect to spatial limitations. The study, now published in the journal Communications Physics, uncovers some extraordinary findings. It highlights how mechanical interactions between colonies can inhibit cellular migration and eventually dictate colony behavior.
Sunkel’s discoveries shed light on how increasing cell colonies cope with overcrowding. This difficulty stems from their indefinite replication and expansion. This growing pressure leads to direct mechanical contacts that impede motion, highlighting a critical aspect of cellular behavior that has implications for various biological processes.
The Mechanics of Cell Growth
In their study, researchers simulated the conditions of an expanding three-dimensional cell colony with a simple computer model. This innovative approach allowed them to simulate the interactions between growth and active migration, providing a clearer understanding of how these factors influence cell behavior. The model’s cells were introduced to a level of force known as motility. This physical force then dictates how far and fast they’re able to travel.
Sunkel expressed surprise at their findings, stating, “Surprisingly, we found that there is a relatively sharp threshold of motility up to which the growth of the colony almost completely inhibits the migration of cells.” As a consequence of this finding, as cells achieve higher densities, their ability to migrate drops drastically.
The study highlights the significance of unpacking these mechanical interactions. These results emphasize an important relationship between development and migration. This interaction is perhaps the most important driver of how cell colonies interact with and mix together across a space. As colonies grow, the interactions between the forces created by each cell and their collective action create a tipping point dynamic that eventually limits this movement.
Implications for Biological Research
Philip Bittihn, the senior author of the resulting collaborative study, is himself a group leader in the Department of Living Matter Physics at MPI-DS. He explained what their results might mean. “In our model, the transition arises all by itself purely from mechanical interactions—a prime example of collective behavior that arises from the interaction of many individual parts,” he explained. This is a great example of how emergent behaviors arise through the dynamics of the collective in biological systems.
This new research builds on previous findings related to how individual cells move. It uncovers the ways that analogous mechanisms might be found in other biological systems. By understanding how growth influences motion within cell colonies, researchers may be better equipped to explore issues related to tissue formation and disease progression.