Current Researches in Modular Biofabrication: Tissue Building Blocks and Bioreactors

Modular tissue engineering (TE) is based on the design, fabrication, and arrangement of replicated microtissue constructs to generate functional tissues. The advantage of this strategy is to produce tissues that more closely mimic the complex structure of native tissues/organs. High-precision technologies such as microfluidics, 3D bioprinting, and electrospinning, which support both cell- and scaffold-based biofabrication methods, are implemented in a bottom-up TE strategy. Bioreactors are used in the last step of the tissue production process. Packed bed perfusion bioreactors are widely applied in bottom-up tissue engineering due to their ability to control perfusion to tissues. Modeling and simulation software packages are used as powerful tools to predict the perfusion and flow distribution to the tissues and to design robust bioreactors. This review imparts on the recent advances in the field of bottom-up TE process and provides comprehensive insights into the cell-based and scaffold-based strategies used for the biofabrication/assembly of tissue building blocks (BBs). Microfluidic devices and 3D-bioprinting technology are mentioned as precise controlling tools in this regard, the promoted applications of which are swiftly growing.