Cells communicate in waves to coordinate movement

Cells communicate like we do. Well, in their own special way. Using waves as their common language, cells tell each other where and when to move. They talk, share information and work together – just like a group of researchers from the Austrian Institute of Science and Technology (ISTA) and the National University of Singapore (NUS). How cells communicate – and how this is important for future projects, e.g. They conducted research on its use in wound healing.

What comes to mind when you think of biology? Animals, plants, theoretical computer models? Lastly, although biology is an important part of research, you may not immediately come into contact with it. It is precisely these calculations that enable us to understand complex biological phenomena, down to the most hidden details. ISTA Professor Eduard Hannezo uses them to understand the physical principles underlying biological systems. His group’s recent work provides new insights into how cells move and communicate inside cells.

During his PhD, Daniel Boocock, along with Hannezo from the National University of Singapore and longtime collaborator Tsuyoshi Hirashima, developed a comprehensive new theoretical model that was published today in the journal PRX Life. This allows a better understanding of long-range cell-cell communication and describes both the complex mechanical forces that cells apply to each other and their biochemical activity.

Cells communicate in waves

Suppose you have a Petri dish covered with cells—a monolayer. It looks like they’re just sitting there. But the truth is, they move, they spin, and they spontaneously produce chaotic behaviors.”

Edouard Hannezo, ISTA Professor

Like a dense crowd at a concert, if one cell pulls to one side, another cell can sense the action and react by pulling in the same or opposite direction. Information can travel in waves—waves visible under a microscope.

„Cells sense not only mechanical forces, but also their chemical environment—forces and biochemical signals that cells send to each other,” Hanneso continues. „Their communication is an intersection of biochemical activity, physical behavior and movement; however, the extent of each communication mechanism and how such mechanochemical interactions work in living tissues has remained elusive until now.”

Predicting operating modes

Driven by the wave scenarios, the scientists’ goal was to establish a theoretical follow-up model that would confirm their previous theory of how cells move from one region to the next. Daniel Boacock explains, „In our previous work, we wanted to explore the biophysical origins of waves and whether they play a role in regulating collective cell migration. However, we did not consider the fluid-solid transition of tissues, inherent in the noise system, or the detailed structure of waves in 2D.”

Their latest computer model focuses on cell movement and the material properties of tissues. By doing so, they discovered how cells interact mechanically and chemically and how they move. They were able to replicate the phenomena observed in Petri dishes, validating a theoretical explanation of cell communication based on the laws of physics.

Testing the theory

For experimental evidence, Boocock and Hanneso collaborated with biophysicist Tsuyoshi Hirashima. To rigorously test whether the new model applies to real biological systems, the scientists used 2D monolayers of MDCK cells—specific mammalian kidney cells—a classical in vitro model for such research.

„If we block a chemical signaling pathway that allows cells to sense and generate forces, the cells stop moving and no communication waves propagate,” explains Hanneso. „With our theory, we can easily manipulate different components of a complex system and determine how the dynamics of the tissue fit together.”

What’s next?

Cellular tissue resembles liquid crystals in some ways: it flows like a liquid, but is arranged as a crystal. Bocock adds: „In particular, the liquid crystal-like behavior of biological tissues has only been studied independently of mechanochemical waves.” Extension to 3D tissues or monolayers with complex shapes, as in living organisms, is an avenue for future study.

Researchers have also begun to improve the model in relation to wound healing. Curing is accelerated in computer simulations where parameters improve information flow. „It will be very interesting to see how well our model works for wound healing in living cells,” Hannezo enthuses.