News

In the intricate world of our immune system, a remarkable team of defender cells tirelessly works together to safeguard our well-being and protect us from infections.  

Among these defenders, a group called T cells plays a pivotal role in recognising and responding to abnormal or infected cells. 

Within the realm of immune T cells there exist unique lineages known as unconventional T cells which include MAIT, NKT, and gamma-delta T cells. These special T cell subsets possess distinct abilities compared to their conventional counterparts and are crucial for maintaining a fully functional immune system. 

Unlike regular T cells that search for abnormal protein patterns as signs of danger, unconventional T cells are able to detect lipid and vitamin B derivatives as early indicators of trouble.  

Although unconventional T cells constitute a significant portion of immune cells in the body, their numbers and proportions vary widely among individuals. Understanding the reasons behind these differences is crucial, as they can influence the quality of an individual's immune response. 

In a new study published in Mucosal Immunology, led by the University of Melbourne’s Calvin Xu and Dr Fern Koay at the Doherty Institute, researchers discovered a fascinating aspect of these cells' behaviour.  

Dr Koay said the research shows that unconventional T cells appear to sense the presence or absence of each other. 

“Removing one type of unconventional T cell subset, such as gamma-delta T cells and/or NKT cells, causes an increase in the numbers of MAIT cells,” Dr Koay said.  

“This indicates that MAIT, NKT, and gamma-delta T cells occupy a similar space in our immune system and vie for the resources needed to maintain their ideal numbers.” 

“Traditionally, scientists have studied these cells individually, focusing on the role of each subset in isolation. However, this recent research highlights the significance of considering unconventional T cells as a collective and understanding their interactions. 

“Just as coordinated efforts among armed forces are crucial to fend off threats, all subsets of unconventional T cells should be seen as complementary or potentially conflicting factors when studying their role in the immune system.” 

The research team, co-led by the University of Melbourne’s Professor Dale Godfrey, Laboratory Head at the Doherty Institute, and Associate Professor Dan Pellicci, Group Leader at the Murdoch Children’s Research Institute (MCRI), believes that these findings have profound implications for immunotherapies aimed at harnessing the power of individual unconventional T cells in various disease settings.  

By comprehending the intricate dynamics and relationships among these specialised T cell subsets, researchers can pave the way for more effective treatments and therapies in the future. 

Peer Review: Mucosal Immunology https://doi.org/10.1016/j.mucimm.2023.05.003

Funding: National Health and Medical Research Council (NHMRC) and the Australian Research Council (ARC).