Cell Dynamics in Chondrocyte Encapsulated Microcarries Used for Cell Delivery: Insights from Computational Modeling

One promising therapeutic method for cartilage regeneration is tissue engineered-based cell delivery using cell encapsulated microgels. Mathematical models are attracting considerable interest in tissue engineering to interpret biological phenomena and determine the key parameters. In this paper, we use a continuum reaction-diffusion model to study the effect of encapsulation parameters on cell response. Nutrient-dependent cell and extracellular matrix (ECM) distribution are modeled. The results indicate that the inhomogeneous distribution of ECM is due to the sharp nutrient gradient, and microgels with a radius smaller than $200\ \mu m$ demonstrate almost homogeneous ECM deposition. Besides the microgel dimension, the effect of initial cell loading was investigated. Numerical simulation of the model reveals that initial cell density has no significant influence on the ECM distribution in small-size microgels. The method presented herein proposes the insight to improve cell-delivery constructs. Also, the results have the potential to provide a design reference for preparing cell encapsulating microgels as building blocks for tissue-engineered cartilage to achieve a construct with homogeneous ECM distribution, which is still a challenge of cartilage tissue engineering.