Eating your greens can boost gut health

Adding leafy greens to your diet is crucial to boost immune cells that keep intestines healthy, a new study has found.
The immune cells, named innate lymphoid cells (ILCs), are found in the lining of the digestive system and protect the body from '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, Lucie Rankin, Dr Joanna Groom and colleagues from the Walter and Eliza Hall Institute's Molecular Immunology division in Australia 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 the food we eat.

Belz said the research found T-bet was essential for generating a subset of ILCs which is a newly discovered cell type that protects the body against infections entering through the digestive system.
"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," Belz said in a statement.

"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," Belz added.

Belz said that the proteins in green leafy (cruciferous) vegetables 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.
"Proteins in these leafy greens could be part of the same signalling pathway that is used by T-bet to produce ILCs," she 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," Belz said.

"Our research shows that, without the gene T-bet, the body is more susceptible to bacterial infections that enter through the digestive system. This suggests that boosting ILCs in the gut may aid in the treatment of these bacterial infections," she said.
"The discovery of these immune cells has thrown open a completely new way of looking at gut biology," she said.
"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," Belz added.
The research was published in the journal Nature Immunology.