(11) An artificial gut to study diarrhoea

The Salmonella typhimurium bacterium is one of the most common causes of diarrhoea worldwide, and there is still no efficient treatment for it. If left untreated, diarrhoea in young children can be life-threatening, especially in low-income countries, where children die of it every day.

This is why new solutions are needed. Developing these necessarily involves animal experiments, the vast majority of which use mice. "Our laboratory needs 3,000 to 4,000 mice each year for research projects," says Wolf-Dietrich Hardt, professor of microbiology at ETH Zurich. "Our NRP 79 project aims to replace them to a large extent. If it is successful and other laboratories adopt our method, thousands more mice could be spared worldwide."

How does the research group plan to achieve its goal? "We are developing a three-dimensional cell culture model of the gut," Hardt explains. The model is based on intestinal stem cells arranged to form an artificial, three-dimensional gut. This model can then be used to investigate how Salmonellae infect the gut, what processes take place and what therapies might help to combat the bacteria. To successfully build their model, the team will have to overcome various hurdles, such as replicating the low-oxygen environment in the gut.

In vitro epithelium for replacing mice in Salmonella diarrhea research