Organ Model

Abstract: Testing of drug effects and cytotoxicity by using cultured cells has been widely performed as an alternative to animal testing However, the estimation of pharmacokinetics by conventional cell-based assay methods is difficult because of the inability to evaluate multiorgan effects An important challenge in the field is to mimic the organ-to-organ network in the human body by using a microfluidic network connecting small-scale tissues based on recently emerging MicroTAS (Micro Total Analysis Systems) technology for prediction of pharmacokinetics Here, we describe an on-chip small intestine-liver coupled model for pharmacokinetic studies To construct an in vitro pharmacokinetic model that appropriately models in vivo conditions, physiological parameters such as the structure of internal circulation, volume ratios of each organ, and blood flow ratio of the portal vein to the hepatic artery were mimicked using microfluidic networks To demonstrate interactions between organs in vitro in pharmacokinetic studies, Caco-2, HepG2, and A549 cell cultures were used as organ models of the small intestine, liver, and lung, respectively, and connected to each other through a microporous membrane and microchannels to prepare a simple model of a physiological organ-to-organ network The on-chip organ model assay using three types of substrate-epirubicine (EPI), irinotecan (CPT-11), and cyclophosphamide (CPA)-were conducted to model the effects of orally administered or biologically active anticancer drugs The result suggested that the device can replicate physiological phenomena such as activity of the anticancer drugs on the target cells This microfluidic device can thus be used as an in vitro organ model to predict the pharmacokinetics of drugs in the human body and may thus provide not only an alternative to animal testing but also a method of obtaining parameters for in silico models of physiologically based pharmacokinetics

Abstract: Physical organ models are the objects that replicate the patient-specific anatomy and have played important roles in modern medical diagnosis and disease treatment. 3D printing, as a powerful multi-function manufacturing technology, breaks the limitations of traditional methods and provides a great potential for manufacturing organ models. However, the clinical application of organ model is still in small scale, facing the challenges including high cost, poor mimicking performance and insufficient accuracy. In this review, the mainstream 3D printing technologies are introduced, and the existing manufacturing methods are divided into "directly printing" and "indirectly printing", with an emphasis on choosing suitable techniques and materials. This review also summarizes the ideas to address these challenges and focuses on three points: 1) what are the characteristics and requirements of organ models in different application scenarios, 2) how to choose the suitable 3D printing methods and materials according to different application categories, and 3) how to reduce the cost of organ models and make the process simple and convenient. Moreover, the state-of-the-art in organ models are summarized and the contribution of 3D printed organ models to various surgical procedures is highlighted. Finally, current limitations, evaluation criteria and future perspectives for this emerging area are discussed.

Abstract: Teaching aids or training aids in the form of organ replicas or organ models each of which is anatomically correct and has the shape, size, vascular components and attachments that are found in live organs in various animals, humans and the like to facilitate teaching or training of students or other individuals in various medical or veterinarian practices. The training aid includes a body cavity model in which the interior is a replica of the inside of the abdominal area with all of the contours that are normally present and the exterior is a replica of the shape of the outside of the abdominal area with a relatively large hole or opening formed in the upper surface to allow for surgical exposure of the organ replicas or models positioned within the abdominal cavity. The organ replicas or models closely simulate living organs in texture, color, consistency and handling properties to form the replicas or models as lifelike as possible with the organ models feeling, handling, capable of being cut and sutured in the same manner as live organs with the colors of the organ models being determined by color matching each organ model with the color of an actual live organ during a surgical procedure. The organ replicas or models are held in the body cavity in apposed relation by retaining structures to maintain the relationship of the organ replicas in the body cavity in a manner similar to live organs being retained in the body cavity.

Abstract: Cell culture is the workhorse of biologists, toxicologists, tissue engineers and a whole host of research fields in both academia and industry. Having explored individual molecular mechanisms inside cells for decades using traditional cell culture techniques, researchers have only just begun to appreciate that the intricate interconnectivity between cells and cellular networks as well as with the external environment is far more important to cellular orchestration than are single molecular events inside the cell. For example many questions regarding cell, tissue, organ and system response to drugs, environmental toxins, stress and nutrients cannot possibly be answered by concentrating on the minutiae of what goes on in the deepest recesses of single cells. New models are required to investigate cellular cross-talk between different cell types and to construct complex in-vitro models to properly study tissue, organ and system interaction without resorting to animal experiments. This chapter describes how tissue and organ models can be developed using the Quasi-Vivo® system and discusses how they may be used in drug toxicity studies.