Engineering living systems on chips: from cells to human on chips

Engineering living systems on chips is an emerging direction with a goal to mimic physiologically accurate biological functions that can be applied to a diversity of applications, such as reliable in vitro drug-screening systems for reducing the need for animal testing. Taking advantages of creative platforms from electromechanical systems technology and from advanced biomaterials to mimic 3D extracellular matrix, these approaches to recapitulating organ-level structures and functions may bring unprecedented benefits to clinical translation of nanomedicines in the pharmaceutical and biomedical industries and to advanced tissue engineering for regenerative medicine. In this review, we discuss recent progress on the engineering of living systems on chips and highlight advanced technologies that integrate a variety of physiological cues including mechanical, chemical, and electrical signals with precise spatiotemporal controls. We also discuss current challenges and future directions of these approaches, analyzing the benefits of continued research in this field.