A gene discovery by Australian scientists indicates that leafy green vegetables could be even better for our health than previously thought.

An immune cell population essential for intestinal health could be controlled by brassicas in the diet researchers at Australia’s Walter & Eliza Hall Institute have found.

The immune cells, named innate lymphoid cells (ILCs), are found in the lining of the digestive system and protect the body from so-called bad bacteria in the intestine.

They are also believed to play an important role in controlling food allergies, inflammatory diseases and obesity, and may even prevent the development of bowel cancers.

Dr Gabrielle Belz and colleagues from the institute’s molecular immunology division have discovered the gene T-bet is essential for producing a population of these critical immune cells and that the gene responds to signals in our food.

Dr Belz said: “In this study, we discovered that T-bet is the key gene that instructs precursor cells to develop into ILCs, which it does in response to signals in the food we eat and to bacteria in the gut. “ILCs are essential for immune surveillance of the digestive system and this is the first time that we have identified a gene responsible for the production of ILCs.”

The research was published this week in the journal Nature Immunology. The proteins in brassicas are known to interact with a cell surface receptor that switches on T-bet, and might play a role in producing these critical immune cells.

Belz said: “Proteins in these leafy greens could be part of the same signalling pathway that is used by T-bet to produce ILCs,” Dr Belz said. “We are very interested in looking at how the products of these vegetables are able to talk to T-bet to make ILCs, which will give us more insight into how the food we eat influences our immune system and gut bacteria.

'The discovery of these immune cells has thrown open a completely new way of looking at gut biology. We are just starting to understand how important these immune cells are in regulating allergy and inflammation, and the implications for bowel cancer and other gastrointestinal disorders such as Crohn’s disease.”