Melbourne researchers have identified a previously unknown role of ‘natural killer’ (NK) immune cells, improving our understanding of how the immune system is regulated to prevent disease.
The discovery may ultimately be used to treat autoimmune diseases like Sjögren’s Syndrome.
Published in Immunity, the Monash University-led, pre-clinical research was conducted in collaboration with the Lions Eye Institute.1 The study identified a new group of immune cells, known as tissue-resident memory natural killer (NKRM) cells.
NKRM cells limited immune responses in tissues and prevented autoimmunity, which is when the immune system attacks the body’s own tissues or organs.
Originally, NK cells were thought to be short-lived cells that circulate in the blood with the sole function of identifying and quickly killing virally infected or damaged cells. The team’s previous research established that NK cells’ role is far more complex, and the latest study demonstrates, for the first time, that a subset of NK cells, NKRM, are critical in regulating immune responses in tissues.
“This is key to preserving tissue function and preventing autoimmunity from developing,” said first author Dr Iona Schuster from the Monash Biomedicine Discovery Institute.2
“While long-lived tissue resident memory T cells (TRM) have been described, the primary known function of these cells is to protect the host against reinfection.
“Our discovery of tissue-resident memory natural killer (NKRM) cells establishes that the function of some memory cells that live in tissues is to protect from excessive inflammation rather than protect against recurring infection.”
The authors said the findings “significantly improved our fundamental understanding of how the immune system is regulated to prevent disease”.
References
1. Schuster, I. S., et al., Immunity: Infection induces tissue resident memory NK cells that safeguard tissue health, Immunity, 10 Feb 2023. DOI: https://doi.org/10.1016/j.immuni.2023.01.016.
2. https://www.monash.edu/news/articles/natural-killer-immune-cells-can-modify-tissue-inflammation-study
