Development of a 3D cell culture system for investigating cell interactions with electrospun fibers

There are many variables to be considered in studying how cells interact with 3D scaffolds used in tissue engineering. In this study we investigated the influence of the fiber diameter and interfiber spaces of 3D electrospun fiber scaffolds on the behavior of human dermal fibroblasts. Fibers of two dissimilar model materials, polystyrene and poly-L-lactic acid, with a broad range of diameters were constructed in a specifically developed 3D cell culture system. When fibroblasts were introduced to freestanding fibers, and encouraged to "walk the plank," a minimum fiber diameter of 10 microm was observed for cell adhesion and migration, irrespective of fiber material chemistry. A distance between fibers of up to 200 microm was also observed to be the maximum gap that could be bridged by cell aggregates--a behavior not seen in conventional 2D culture. This approach has identified some basic micro-architectural parameters for electrospun scaffold design and some key differences in fibroblast growth in 3D. We suggest the findings will be of value for optimizing the integration of cells in these scaffolds for skin tissue engineering.