Cell spreading on biocompatible materials studied by computer simulations

The goal of tissue engineering is to create functional tissue constructs that can be implanted into the human organism. A classical approach to tissue engineering consists in the culturing of cells on porous scaffolds made of biocompatible and biodegradable materials. An important step in this approach is the cell seeding of scaffolds. It has been shown that uniform seeding leads to faster development of the tissue construct and superior mechanical properties in comparison to non-uniform seeding. The success of seeding depends on cell spreading on the scaffold's material. This paper presents a computational model of a biological system used in experiments on cell spreading on biomaterials. The model describes a cell aggregate placed on a parallelepipedic slab of biomaterial bathed in cell culture medium. Experiments suggest that cell spreading results from a competition between cell-cell and cell-biomaterial interactions, in accord with Steinberg's differential adhesion hypothesis, which considers that the cellular system evolves towards the state of minimum energy of adhesion. Using the Metropolis Monte Carlo method, we simulated cell spreading on a biomaterial for different values of the cell-cell and cell-biomaterial interactions and found that cell spreading is governed by the difference between half the cell-cell cohesion energy and the cell-biomaterial adhesion energy.