Current trends in 3D bioprinting and endeavours to whole tissue printing.

Abstract

Human tissues and organs are complex structures of cells and extracellular matrix components, arranged in a specific composition to exert its functions. In the field of tissue engineering, 3D bioprinting, a type of additive manufacturing, has shown great potential to produce complex structures due to the high spatiotemporal control. The unmatched resolution in printing cell-laden bioinks allows for creation of models with higher physiological resemblance and functionality. With the high demand for tissue and organ transplants, bioprinting is considered a promising tool to fulfil some of these needs. However, bioprinting is currently not routinely utilized in the clinic to produce transplantable tissues, and several issues have to be overcome to enable this. In this Review, we will first provide an overview of model design and printing techniques to give a better understanding of the printing factors to take into consideration. Subsequently, the matrix requirements for printing, and cell functionality and viability will be addressed. Finally, we will discuss current advances made in tissue bioprinting, showcased by some innovative examples, and address challenges in biomaterials, cell biology, and engineering that have to be overcome to bring bioprinting closer to the clinic.