Biofabrication of tissue perfusion systems and microvasculatures

Abstract Realization of the full potential of tissue and organ fabrication, for either tissue modeling or regenerative medicine applications, requires solutions enabling perfusion of the tissue bed to overcome fundamental limitations of diffusion. While there are many challenges related to perfusing a fabricated tissue, establishing a perfusion system scaled to the cellular level remains critically important. Numerous strategies involving a variety of fabrication methods compatible with living systems have emerged to address this challenge, many of which can be classified into two general categories: engineering of channel networks and fabrication of native-like microvasculatures. Regardless of the approach taken, understanding the basis of tissue perfusion via the microvasculature in native tissues is invaluable in guiding the fabrication process. While these approaches have brought us much closer to meeting these challenges, there remains a need for further innovative solutions involving materials, tissue biology, biofabrication (including design and make strategies), and imaging and more to effectively fabricate human-scale, functional, vascularized tissues and organs.