Ask most people for a list of the names of body organs that they know, and chances are you won’t find the name of “thymus” in there—and frankly I wouldn’t blame them. It certainly isn’t one of the more recognizable organs, but its fame shouldn’t detract from its crucial role in the body.
The thymus, being one of the lymphoid organs of the immune system, is responsible for maturing T cells, otherwise known as thymus cell lymphocytes. These cells play a pivotal role in the adaptive immune system, allowing our body to put up a fight against foreign invaders that might otherwise cause harm within. This is why the organ is also given the nickname of being the body’s “boot camp.”
Adding to this, researchers from the Walter and Eliza Hall Institute of Medical Research (WEHI) may have found something that could be revolutionary should further research prove fruitful; their findings, published in the journal Science Immunology, show that the enzyme KAT7 is needed to teach these T cells not to attack otherwise healthy tissue. The results may give doctors and medical experts a way to curb autoimmune conditions like multiple sclerosis and type 1 diabetes.
“We showed how a KAT7 inhibitor […] was able to stop [the autoimmune regulator (AIRE) protein] from switching on the genes needed to properly train immune T cells. Stopping this process sent the immune system into overdrive, leading to immune T cells going rogue and causing a range of autoimmune conditions in pre-clinical models. This shows a clear link between KAT7 and AIRE in maintaining immune tolerance,” said WEHI associate professor and study co-author Tim Thomas.
Thomas was joined by co-author and associate professor Daniel Gray, with WEHI’s Dr. Melanie Heinlein leading the whole research endeavor. The team collaborated with fellow researchers from Monash University and the Weizmann Institute of Science. (The KAT7 enzyme used in the study was developed in collaboration with Monash‘s Jonathan Baell.)
“Potential applications of this knowledge include organ-specific autoimmune diseases such as Type 1 diabetes and multiple sclerosis, as well as cancer immunotherapy.”
Daniel Gray, associate professor from the Walter and Eliza Hall Institute of Medical Research, discussing the potential of their novel findings about the KAT7 enzyme in the thymus
Dr. Heinlein added: “Like a training coordinator, KAT7 directs AIRE to the thousands of genes that must be activated for the ‘boot camp’ to run smoothly. KAT7 does this by tagging the genes that AIRE needs to ‘switch on’ for the preview of the body’s proteins to work. When all goes to plan, immune T cells are trained not to fight any normal tissues they could encounter in the body, ensuring they do not cause autoimmune disease.”
This, then, presents an interesting opportunity for future treatment for autoimmune diseases. Instead of allowing T cells to attack willy-nilly, targeted KAT7 treatment can either dampen or boost a patient’s immune response as needed.
Gray discussed the exciting possibilities made available through their unique discovery: “Potential applications of this knowledge include organ-specific autoimmune diseases such as Type 1 diabetes and multiple sclerosis, as well as cancer immunotherapy. In the latter scenario, the immune system could be supercharged to combat cancer by blocking KAT7 in the thymus.”
(Read more about unique discoveries in the human body by reading about the rare aging syndrome possibly influenced by “quadruple helix” DNA, and about the role that the liver may play in the onset of Alzheimer’s disease.)
References
- ‘Boot camp’ enzyme prevents autoimmune conditions. (2022, January 31). [Text]. The Walter and Eliza Hall Institute of Medical Research. https://www.wehi.edu.au/news/boot-camp-enzyme-prevents-autoimmune-conditions
- Heinlein, M., Gandolfo, L. C., Zhao, K., Teh, C. E., Nguyen, N., Baell, J. B., Goldfarb, Y., Abramson, J., Wichmann, J., Voss, A. K., Strasser, A., Smyth, G. K., Thomas, T., & Gray, D. H. D. (2022). The acetyltransferase KAT7 is required for thymic epithelial cell expansion, expression of AIRE target genes, and thymic tolerance. Science Immunology. https://www.science.org/doi/abs/10.1126/sciimmunol.abb6032
- Lavars, N. (2022, February 1). Targeting ‘boot camp’ enzyme could fight autoimmune diseases and cancer. New Atlas. https://newatlas.com/medical/boot-camp-enzyme-immune-response-autoimmune-disease-cancer/
