Human organ-on-a-chip: Around the intestine bends

The small intestine is the central component of the gastrointestinal (GI) tract (gut) where nutrients are absorbed into the body. Its functional structure is mainly based on its extremely extended surface area, further increased by a specific carpet of villi, responsible for the translocation of nutrients from the GI lumen into the bloodstream. Also, in the small intestine, the absorption processes of the orally administered drugs are basically related to the pharmacokinetics [1]. The deficit of cell culture methods to maintain in vivo–like functions forces researchers to optimize and apply methods in which cells are seeded and cultured under controlled and dynamic fluid flow [2]. Moreover, the lack of predictive human organ models has increased the necessity of approaches for proper mimicking of organ function in vitro, studying physiological parameters that regard mechanical, chemical and physical stimuli crucial for differentiation, morphology and function of the epithelia [3]. In this work we present a Gut-On-Chip (GOC) device, equipped with ITO (Indium tin Oxide) electrodes patterned by wet etching techniques, as a multifunctional microsystem for monitoring epithelial parameters. The potential to support cells adhesion, growth and polarization of a functional monolayer is also investigated in the Caco-2 epithelial-like cell line by in-device seeding and culture. In a perspective, this first prototype has established the basis for several technology integrations to study complex cellular phenomena targeted in key physiological topics (e.g. the tight interplay of different physical effects during mechanotransduction processes) and in pharmacological open issues such as drug absorption and metabolism.