Enzyme that relays signals between cells' mitochondria could help fight disease.
They have found that the enzyme receptor-interacting serine-threonine kinase-3 (RIPK3) has a role not previously envisaged: sending messages between the cells' mitochondria "powerhouses" and the immune system, according to an article published in the journal Nature Communications.
It appears that the communication carried out by RIPK3 has two functions: first, to launch immune responses against tumors, and second, to regulate inflammatory responses that may result in autoimmune diseases.
RIPK3 was already known to control the induction of necroptosis, which is a form of programmed cell death. Necroptosis protects the body from harmful mutations and infections. However, its role in the immune system is only now coming to light.
In order to better understand RIPK3, researchers studied RIPK3-deficient mice.
RIPK3 regulates activity of killer T cells
They found that RIPK3 appears to regulate the activation of natural killer T cells (NKTs). NKTs are immune cells that play a role in both the development of autoimmune diseases and the destruction of cancer.
It would seem that RIPK3 regulates the activity of a mitochondrial enzyme known as PGAM5, and this, in turn, triggers the expression of inflammatory cytokines in NKTs. It is now hoped that understanding this pathway will lead to better ways to control NKTs in order to attack tumors.
Understanding of the pathway may also make it possible to disrupt it in order to block inflammation.
By detecting the gene for RIPK3, or inhibiting other parts of the pathway, the researchers found that they could actually protect mice from the induction of acute liver damage. This suggests a role for RIPK3 in autoimmune diseases.
The Scripps Research Institute (TSRI) Assistant Professor of Immunology Young Jun Kang, who collaborated on the study with the lab of TSRI Institute Professor Richard A. Lerner - who is also Lita Annenberg Hazen Professor of Immunochemistry - says:
"This finding could be helpful for developing strategies to target cancer and inflammatory diseases."
The next step will be to focus on understanding the details of this new signaling pathway, which may pave the way for new therapies to either enhance its cancer-killing role or reduce its role in inflammation.
Medical News Today recently reported on research showing aspirin is potentially effective against some types of cancer due to the relationship between T cells, the immune system and cancer