Exploring Organ-on-Chip Systems as Functional Bioassays for Drug Screening: Principles and Models

Organ-on-chip (OoC) systems are rapidly becoming an avant-garde tool for mimicking the organization and function of human organs in vitro. Through integration of microfluidic techniques and living human cells, they enable physiologically realistic conditions for drug testing, which simply can not be achieved using standard 2D cultures or animal models. This review provides a summary of the principles and constructions of liver-, heart-, lung-, and gut-on-chip systems, and discusses how each system recapitulates specific organ function. Special attention is given to their utilization as functional bioassays for drug discovery. By linking together organ chips to form fluidic circuits, researchers can emulate inter-organ pharmacokinetics and dynamic biological responses that are essential for drug metabolism, efficacy testing, and toxicity testing. While challenges still exist in ruggedizing, scaling up and cell sourcing, OoC technologies are moving towards predictive and personalized preclinical testing platforms. Such systems have great promise to increase the predictive and efficiency aspects of pharmacology and improve the relevance of pharmacological evaluations to the human condition.