Bioreactor-free tissue engineering: directed tissue assembly by centrifugal casting

Casting is a process by which a material is introduced into a mold while it is liquid, allowed to solidify in a predefined shape inside the mold, and then removed to give a fabricated object, part or casing. Centrifugal casting could be defined as a process of molding using centrifugal forces. Although the centrifugal casting technology has a long history in metal manufacturing and in the plastics industry, only recently has this technology attracted the attention of tissue engineers. Initially, centrifugation was used to optimize cell seeding on a solid scaffold. More recently, centrifugal casting has been used to create tubular scaffolds and both tubular and flat multilayered, living tissue constructs. These newer applications were enabled by a new class of biocompatible in situ crosslinkable hydrogels that mimic the extracellular matrix. Herein the authors summarize the state of the art of centrifugal casting technology in tissue engineering, they outline associated technological challenges, and they discuss the potential future for clinical applications.