Associate Prof. Ioan Kosztin
Department of Physics & Astronomy
University of Missouri – Columbia
Columbia, MO

Monday, September 27, 2010
3:00 pm (CT)
3269 Beckman Institute

Abstract

Theoretical and computer modeling of multicellular systems can provide valuable tools for interpreting and guiding in vitro experiments relevant to embryogenesis, tumor growth, angiogenesis, cell sorting and self-assembly of artificial cell aggregates used in bioprinting. The property of tissue liquidity, which is the result of cellular adhesion and motility, is manifest in such experiments. Here we introduce a novel approach, referred to as the cellular particle dynamics (CPD) method, for describing the real time dynamics of multicellular living systems. In CPD cells are modeled as an ensemble of cellular particles that interact via short-range contact interactions, characterized by an attractive (adhesive interaction) and a repulsive (excluded volume interaction) component. The time evolution of the spatial conformation of the multicellular system is determined directly by recording the trajectories of all cells through integration of their equations of motion. The viability of the CPD method is demonstrated in the case of fusion of two spherical multicellular aggregates. Comparison between the CPD simulation and experimental results provides a direct way to relate cellular level model parameters to experimentally measurable tissue level biophysical quantities (e.g., surface tension, viscosity and shear modulus). By design, the CPD method is rather flexible and most suitable for multiscale modeling of multicellular system. The spatial level of detail of the system can be easily tuned by changing the number of cellular particles in a cell. Thus, CPD can be used equally well to describe both cell level processes (e.g., the adhesion of two cells) and tissue level processes (e.g., the formation of 3D constructs of millions of cells through bioprinting).