A harmless variety of Escherichia coli can be used to protect the intestine from a variety of bacteria of a pathogenic nature. This is the discovery published in a new study published in mBio.
According to the researchers, a particular strain of Escherichia coliharmless to the intestinal tissue, can protect this organ against a strain of Escherichia coli enterohemorrhagic, a pathogen that produces the Shiga toxin, which often affects children.
The protective strain, called Nissle, was isolated in 1917 by scientist Alfred Nissle from the excrement of a German soldier. Over the years it has been used as a probiotic and also to treat various intestinal disorders such as ulcerative colitis.
To see if this strain could also protect the intestines fromEscherichia coli pathogens or other pathogenic bacteria, the researchers conducted experiments on the human intestinal organs, essentially miniature models of biological tissue derived from stem cells that mimic the tissue of real organs.
Researchers at the University of Cincinnati first injected the “beneficial” strain by verifying that it was harmless and obtaining a positive response. They then injected theEscherichia coli enterohemorrhagic, the pathogenic strain, in the intestinal organ pretreated with the Nissle strain. The researchers discovered that the enterohemorrhagic strain could no longer destroy the epithelial barrier, even if the bacteria of the Nissle strain ended up disappearing.
“Basically, Nissle was killed by pathogenic bacteria, but it made the gut more resistant to damage,” said Alison Weiss, one of the researchers who conducted the study with Suman Pradhan.