Sugar -caking hides a cellular RNA from the immune system

For our immune system, naked RNA is a sign of viral or bacterial invasion and must be attacked. But RNA also has our own cells. To repel trouble, our cells wear RNA in sugars, Vijay Rathinam and colleagues with the Uconn School of Medicine and Ryan Flynn in the Hospital report for children in Boston on August 6.

Ribonucleic acid (RNA) is a family of large biological molecules fundamental for all life forms, including viruses, bacteria and animals. Viruses as diverse as the Odra, Flu, Sars-Cov-2 and rabies have RNA, so the immune system begins to attack when he sees RNA in the bloodstream or in other inappropriate locations. But our own cells also have RNA, sometimes displaying it on their surface, even, so that the wandering immune cells can see – and yet the immune system ignores them.

“Diagnosis of RNA for a sign of infection is problematic, because every single cell in our body has RNA,” says immunologist School of Medicine Uconn Vijay Rathinam. The question is: How does our immune system distinguish our own RNA from dangerous invaders?

Previous research conducted by Boston Children’s Hospital and researchers of the Stanford University Ryan Flynn and Carolyn Bertozzi noticed that our bodies add sugars to RNA. These ribbed RNA sugar (also known as glycoslated RNA or glycade) are displayed on the cell surface and do not seem to provoke the immune system.

Rathinam and his colleagues wondered if sugar had somehow protected from the immune system. It can be a strategy that the body uses to prevent the provocation of our RNA inflammation.

When Vincent Graziano, a student’s doctorate in the Rathinama laboratory and the main author on the newspaper, took Glikorna from the breeding of human cells and blood, cut off the sugars and re -introduced them to the cells, the immune cells attacked him. The immune cells ignored the same RNA when it was coated with sugar.

Sugar -Curating hides our own RNA from the immune system. “

Vijay Rathinam, immunologist, Uconn School of Medicine

This is especially important for our body, because the cells are often covered with glychers. When the cells die and are cleaned by the immune system, RNA covering sugar prevents unnecessarily stimulating inflammation.

Discoveries can help thinking about autoimmune diseases. Some autoimmune diseases, such as lupus, are associated with specific RNA and dead cells that repeal the immune system. Now that scientists understand the role of glycoslation of RNA in deviating the attention of the immune system, they can check whether this strategy goes wrong in some way, and if so, how can it be fixed.

The study was conducted in cooperation with the Laboratories of Ryan Flynn, Thomas Carell, Franck Barrat, Beiyan Zhou, Sivapriya Kailasan Vanaja, Michael Wilson and Penghua Wang and was financed by subsidies from the National Institutes of Health.