Researchers find how body tolerates food without immune system attack

Jerusalem, May 28 (IANS) Israeli scientists have pinpointed a crucial network of immune cells that allows humans to digest food safely without triggering harmful reactions.

The discovery, led by researchers at the Weizmann Institute of Science (WIS), sheds new light on oral tolerance, the body's ability to recognise food as harmless and prevent an immune system attack, Xinhua news agency reported.

This vital system stops everyday foods from causing inflammation while still letting the immune system fight off infections.

The breakthrough could pave the way for new treatments for food allergies, sensitivities, and disorders like celiac disease. By understanding how this system works, scientists hope to correct what goes wrong when the body mistakenly attacks food.

"If an aggressor fires across the border, he will be swiftly neutralised, peace accords notwithstanding. The immune system operates on a similar principle," said Dr. Ranit Kedmi from Weizmann’s Systems Immunology Department.

For a long time, scientists believed certain immune cells called dendritic cells were responsible for oral tolerance. However, even when these cells were removed in animal studies, the body still tolerated food.

Now, the WIS researchers, in a study preprinted by the journal Nature, have identified another group of immune cells, called ROR-gamma-t cells, as the real drivers of this process.

These rare cells kick off a chain reaction involving four different cell types, ultimately preventing the body's attack cells, known as CD8 cells, from reacting to food.

When this system fails, it can lead to food allergies, sensitivities, or diseases where the body mistakenly attacks food proteins, such as gluten.

The researchers also found that during an infection, the immune system can temporarily override food tolerance to fight off microbes, before returning to its normal peacekeeping role.

“Apparently, there is much more division of labor in the immune system than previously appreciated,” Kedmi explained. “It’s not that dendritic cells always decide whether or not to attack foreign substances. Rather, completely different players – specific, rare cells – are dedicated to launching a mechanism that makes sure we can consume food safely,” she added.

--IANS

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