We usually think of bacteria as ‘bad’, causing infections and making us ill. But our bodies are also packed with ‘good’ bacteria that help to keep us healthy. By studying mice, scientists have discovered that reducing the number of different bacteria in the gut increases the chances of severe parasitic infections by affecting the production of protective mucus that normally prevents parasites from getting into gut cells. These images show cross-sections through the wall of the gut, stained with pink or brown dyes that highlight mucus-producing cells. The animals sampled in the top two panels were treated with antibiotics to kill off some of their gut bacteria. They have far fewer mucus-producing cells than untreated animals (lower panels) and are more susceptible to catching Entamoeba histolytica – the parasite that causes amoebic dysentery. If this battle also happens in human guts then boosting bacteria could be a way to protect against parasites.
BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
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