Biological & Soft Matter Seminar: Diffusion in Anisotropic ECM Environments

Abstract:

In vivo, specialized Eukaryotic cells are embedded in a matrix environment, where they grow and develop. Generally, this extracellular matrix (ECM) is an anisotropic fibrous structure, in which macromolecules and biochemical signaling molecules diffuse through. The ECM network geometry is continuously modify by cells, via mechanical interactions, which lead to a potential link between biomechanical and biochemical cell-cell interactions. Using random walk on a 3D lattice, we implement elongated fixed obstacles that mimic the fibrous ECM structure, and measure both diffusion of a tracer molecule and the first passage time it needs to reach a target location from an initial position. We observe strong dependency on the target finding time as a function of the fiber anisotropy, fiber density and fiber size, suggesting a cell signaling regulatory mechanisms.