Review of Cell and Organ Printing Patents

Cell or organ printing is any technology that enables a user to deposit precise patterns of living cells or cell aggregates throughout three dimensional (3D) tissue engineering scaffolds. Traditional tissue engineering approaches utilize random cell seeding (flooding) of porous scaffolds to promote cell attachment. While this approach does allow cells to diffuse and attach throughout macroscopic scaffolds, there are both biological and material limitations of this approach, namely the inability to mimic the cellular/molecular heterogeneity and structure (vascularization, sinuses, etc.) found in natural tissue. Cell printing offers the unique possibility of creating tissue scaffolds with pre-built cellular/molecular heterogeneity and structure through layer-by-layer fabrication. The aim of this review is to illustrate the different approaches to building tissue scaffolds via cell printing, describe the specific cell printers in the peer-reviewed and patent literature with their demonstrated capabilities, and then discuss the future of these technologies with respect to important biomedical applications such as tissue engineering, organ replacement and tissue microdissection.