An accidental discovery by Melbourne researchers has revealed the purpose of ‘mystery’ immune cells in the gut, shown how our immune system interacts with the complex bacteria ecology found there, and opened new paths for drug discovery.
Our guts, lungs and mouths are lined with mysterious immune cells that make up to 10 per cent of the T cells in our immune system. These immune cells, known as mucosal-associated invariant T cells (MAITs), detect reactive intermediates in the synthesis of vitamin B2 (riboflavin) that is made by many invasive bacteria and fungi.
Humans and other mammals use, but do not make, riboflavin, so the presence of these precursors indicates invasive bacteria or fungi. That’s when the MAIT cells swing the immune system into action against foreign invaders.
The team, from the University of Melbourne and Monash University, won the 2013 Australian Museum University of New South Wales Eureka Prize for Scientific Research.
“In the spirit of Pasteur, the team exploited an accidental discovery to reveal a new paradigm for how our immune system can function,” Frank Howarth, director of the Australian Museum, says.
The team members are continuing their work as part of a new Australian Research Council Centre of Excellence in Advanced Molecular Imaging.