Organ-on-a-chip ? the beginning of the end for animal testing?

An organ-on-a-chip is a device that enables stem cell-derived in vitro models of organ systems to be produced. This allows for key organ characteristics to be studied in detail with the hope that one day they will replace animal models currently used for medical research.

A recent study investigated the features of a small-intestine-on-a-chip, created by using a 3D silk scaffold to cultivate human stem cell-derived small intestine-like ‘enteroids’. Analysis showed that the various intestinal cells had differentiated effectively into a mature epithelial layer containing all four of the major intestinal cell types, alongside a number of other features such as tight junctions, polarised microvilli and digestive enzyme secretion.

Upon infection of the intestinal model with E. Coli, the authors observed the upregulation of several genes involved in the innate immune response alongside a marked antibacterial response. The model closely impersonates the natural human response to an invading gut pathogen, even though it is much more simplistic. The authors hope that these models can be used to study the pathogenesis of inflammatory bowel disease and to increase our understanding of commensal and pathogenic microbe interaction.