Our intestine wall is made up of two types of cells – cells covered in finger-like villi which specialise in absorption, and smooth cells which shuttle microbes across the gut lining to be dealt with by our immune system. These smooth cells are a bit like security guards, keeping an eye out for any trouble. However, several pathogens are known to exploit them, hitching a ride for an easy way to infect and colonise tissues. Food-poisoning bacteria Salmonella typhimurium, (pictured in yellow) go one step further – they secrete a protein which changes villi-covered cells into transporter cells, making it even easier for them to infect the host. Here, just 120 minutes after infection, is a cell mid-way through the transition with just a few villi left. Understanding this interaction could help in developing oral vaccines which are taken up by the transporter cells.
Written by Sarah McLusky
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