Jason Ko

Poster Presentation

Simulating Cell Sorting by Differential Adhesion Using Continuous Mathematical Models

As organisms develop, cells must adopt specific fates, as well as positions in space. The differential adhesion hypothesis states that the movement of cells into their proper places is governed, at least in part, by intercellular adhesion. These adhesive forces are controlled by the expression of surface proteins, or the contraction of the cell surface due to the action of the cytoskeleton. If there are two populations with different adhesiveness, the population with higher adhesiveness will cluster tightly together, while the population with lower adhesiveness will form an encircling outer layer. This phenomenon of cell sorting has been implicated in the development of the three major germ layers. It has also been implicated in the movement of blastema, the stem cell clusters central to regeneration. Thus, studying cell sorting can help us better understand core developmental processes.

While the exact mechanisms that underlie differential adhesion are not completely understood, we can still capture the tissue-level effects of cell sorting using mathematical modeling. Here we show a novel simulation framework where cell-cell adhesion is specified by a single equation, which is modulated by the dynamic presence of different levels of morphogens. Using computer simulations of a continuous mathematical model in space and time we demonstrate how populations of cells interact to form a diversity of forms and shapes. We believe that this model more closely illustrates the mechanisms behind many fundamental biological processes, such as separation of the ectoderm from the endoderm, and wound healing.