Understanding Tissue Behaviour Incorporating Different Kinds of Cellular Interactions

Abstract

One of the most fundamental issues for developmental biology is the ability of cells to form tissues. However, the exact reasons for cells to adhere to one another in tissues and to migrate once a piece of tissue in placed on a substrate is not clear. We demonstrate that the rate of cellular aggregation over 2d substrate or 3d medium reflects a competition between cell-cell and cell-substrate adhesions. Efficient process of collective cell migration can be dictated by incorporating different factors like mechanical, chemical and physical interaction present in the environment of cells. The primary motivation of our work is to exploit the special mathematical feature of different kind of interacting forces. Studies have uncovered anchorage-dependent cells are capable of sensing and responding to changes in the biophysical properties of their substrate through integrin receptors. We propose a model allowing the cells to migrate through ecm and expose to a range of well-defined adhesive, chemical and mechanical conditions. We mainly focus on the contribution of these factors to the large scale organization of motile cells. Fibroblast originated biological cells can exert strong mechanical forces on their surrounds. We assume that the elastic medium in our model also propagates strain similar to an isotropic elastic medium. Some other kind of cellular aggregation forms depending on diffusible chemical signals and chemotaxis. We assume that the signaling species is transported diffusively from one cluster to another. Anchorage dependent cells must adhere to their substrate and generate tension through integrin receptors in order to migrate. Cells extend their lamellipodia and grab the substrate through integrins, generate cellular contraction. We consider cell-substrate adhesivity alongside with cell-cell cohesivity for cellular aggregation and spreading.