Fabricating large-scale three-dimensional constructs with living cells by processing with syringe needles

Three-dimensional (3D) cell constructs composed only of cells and cell-secreted extracellular matrix have been attractive biomaterials for tissue engineering technology; however, controlling construct morphology and eliminating dead cells after fabrication remain a challenge. It has been hypothesized that moderate stress could shape constructs and eliminate dead cells. The purpose of this study was to establish an easily available technology for shaping 3D cell constructs and eliminating dead cells postfabrication. To achieve these objectives, spherical cell constructs composed of L-929 fibroblasts were processed using different sized syringe needles. Our results revealed that large-scale rod-shaped cell constructs could be fabricated, and that their diameters could be controlled according to the size of the syringe needle. Additionally, cell viability assays showed that >94% of cells in the rod-shaped constructs were viable, suggesting that dead cells, which have low adhesion force, were dispersed when compressive stress was applied during passage through the needle. The technology described in this study will be promising for future tissue engineering, especially for fabricating elongated tissues such as nerves and blood vessels.