This gut on a chip, designed by Donald Ingber from Harvard University in the US, and colleagues, is quite special as it mimics the gut’s structure, conditions and even the peristaltic motions (gut muscles contracting and relaxing in turn along the tube to move food along). The team hopes that it’ll replace animal guts used in studies, such as seeing how drugs are absorbed into the body through the gut.
The team made the device from two microfluidic channels separated by a porous flexible membrane coated with extracellular matrix and lined with human intestinal epithelial cells. To recreate the natural gut’s environment, they had fluid flowing through the tube at a low rate and they exerted a strain on the tube at constant intervals to mimic peristalsis.
— A schematic of the gut-on-a-chip showing the flexible porous extracellular matrix-coated membrane lined by gut epithelial cells crossing horizontally through the middle of the central microchannel, with vacuum chambers on both sides. The mechanical strain is exerted by applying suction to the vacuum chambers
Under these conditions, a columnar epithelium developed, which grew into folds – similar to the structure of intestinal villi. Then, the team grew a normal intestinal microbe (Lactobacillus rhamnosus) on the epithelium’s surface, which survived for around a week (not an easy thing to achieve, they say).
Together, these components make a more realistic model than current systems that could be used for absorption and toxicity studies, transport, drug tests and to develop new intestinal disease models.
If you want to find out more about body parts on chips and their uses, the journal Lab on a Chip has loads of papers on the topic.