"Theoretical and Computational Approaches for Modeling Engineered Cartilage Growth and Optimizing Culture Conditions"

Gerard A. Ateshian, PhD
Department of Mechanical Engineering
Columbia University

Much progress has been achieved in cartilage tissue engineering over the last two decades, ranging from the identification of suitable cell sources and scaffolds, to culture conditions and timing of growth factor delivery.  Today, cartilage tissue constructs can be grown to reproduce native levels of either proteoglycan or collagen content, though not both.  As a result, mechanical properties of these constructs approach those of native tissue only for some subset of the desired properties, such as the equilibrium compressive modulus, but not the tensile modulus or the hydraulic permeability.  The best functional properties are typically obtained with smaller constructs where the competing factors of nutrient transport and consumption are less constraining.  To address the remaining challenges of engineering tissue constructs with anatomically relevant dimensions and a comprehensive range of functional properties, we have combined experimental measurements with computational modeling that accounts for critical factors that influence the outcome of tissue growth, such as nutrient and growth factor availability.  This presentation describes the challenges of formulating a finite element framework for tissue growth, verifying model accuracy, informing the models with experimental data and validating them against independent experimental measurements.