Researchers find a cell-cell repulsion phenomenon that creates several cell tissue structures
A group of researchers from the Department of Condensed Matter Physics and the Institute of Complex Systems (UBICS) of the University of Barcelona, in collaboration with researchers from the University of Leuven (Belgium), created a generic model which allows understanding the creation of different tissues with a few parameters characterized by the mechanic properties of cells and their interactions. The work has been published this December in Proceedings of the National Academy of Sciences (PNAS).
A group of researchers from the Department of Condensed Matter Physics and the Institute of Complex Systems (UBICS) of the University of Barcelona, in collaboration with researchers from the University of Leuven (Belgium), created a generic model which allows understanding the creation of different tissues with a few parameters characterized by the mechanic properties of cells and their interactions. The work has been published this December in Proceedings of the National Academy of Sciences (PNAS).
Cells can create tissues with a wide range of different structures and dynamics according to their biological function. For instance, some are spread uniformly during the embryonic development. Other cells create epithelial tissues, continuous monolayers which act as a physical barrier, like skin. In some conditions, there can be an apparition of cell sphere aggregates, which can be associated to tumours and the development of a cancer. Therefore, understanding the physics of the creation of different kinds of tissues is a first step to go forward in the understanding of the development of tissues or some diseases.
In particular, says UBICS researcher Ignacio Pagonabarraga, who led the research “in the model we had in mind the fact that cells are deformable and can overlap and they are able to move over a substrate and join other cells”. Moreover, he adds that “we also thought that in some cases there is a tendency to move in opposed directions when they touch another cell”. This specific interaction, called contact inhibition of locomotion, has been recently identified as a relevant mechanism for several collective behaviours in cell tissue. In short, according to Ricard Alert, researcher at the Department of Condensed Matter, who has participated in the study, “the developed model allowed to understand how, with simple “ingredients” a wide range of different tissue structures and dynamics can come up -for example, cell clusters, gel-like networks, collectively migrating monolayers, and 3D aggregates, associated to tumours”.
In the study, the researchers calculated how the contact inhibition of locomotion acts as an effective repulsion force, which tends to enable cells to spread. In fact, the model allowed getting analytical predictions of the transitions between non-cohesive, cohesive and 3D cell arrangements. Throughout simulations, they also found out that contact inhibition of locomotion creates tension in tissues and provokes collective movements of cells in cohesive tissues, such as the ones that happen during the process or cicatrisation of wounds.
Article reference:
B. Smeets, R. Alert, J. Pešek, I. Pagonabarraga, H. Ramon, R. Vincent. «Emergent structures and dynamics of cell colonies by contact inhibition of locomotion». Proceedings of the National Academy of Sciences of the United States of America (PNAS), December 2016. DOI: 10.1073/pnas.1521151113