sugar coated RNA immune system autoimmune disease research

How Sugar-Coated RNA Tricks the Immune System: A Breakthrough in Autoimmune Disease Research

Introduction

The immune system interprets unprotected RNA as evidence of viral or bacterial invasion, prompting an attack. However, since our cells also possess RNA, they protect it by encasing it in sugars, according to Vijay Rathinam's team at the UConn School of Medicine and Ryan Flynn at Boston Children's Hospital writing in Nature.

RNA and the Immune System

What is RNA?

Ribonucleic acid (RNA) is a class of large biological molecules essential to life in all its forms—viruses, bacteria and animals alike.

How the Immune System Reacts to RNA

Viruses such as measles, influenza, SARS-CoV-2 and rabies all carry RNA, prompting the immune system to respond aggressively when it detects RNA in the bloodstream or other inappropriate sites. Yet our own cells also contain RNA, sometimes presenting it openly on their surface, visible to patrolling immune cells—remarkably, without provoking attack.

The Challenge of Distinguishing Self from Invader

The Central Question

"Identifying RNA as an indicator of infection poses a challenge, given that every cell within the human body contains RNA," notes immunologist Vijay Rathinam from the UConn School of Medicine. "The real question is how the immune system tells apart our own RNA from that of harmful intruders."

Discovery of Glycosylated RNA

The Role of Sugars in Immune Evasion

Previous investigations by Ryan Flynn of Bostan Children's Hospital and Carolyn Bertozzi of Stanford University discovered that our bodies affix sugars to RNA. These sugar-coated RNA, termed glycosylated RNAs or glycoRNAs, are found on cell surfaces yet appear to evade immune detection.

Research Hypothesis

Rathinam and his team speculated that the sugars might be shielding glycoRNAs from immune detection—a possible mechanism by which the body avoids inflammation caused by its own RNA.

Experimental Findings

Sugar Removal Test

When Vincent Graziano, a doctoral student in Rathinam's laboratory and lead author of the study, removed the sugars from glycoRNA taken from human cell cultures and blood, then reintroduced it into cells, immune cells attacked it. The same RNA, when sugarcoated had previously been ignored.

Key Insight

"The sugar coating conceals our own RNA from detection by the immune system," says Rathinam.

Significance for the Human Body

Protecting Against Unnecessary Inflammation

This is especially important for the body, as cells are frequently coated with glyconRNAs. When they die and are cleared away by the immune system, the RNA's sugar covering stops them from needlessly triggering inflammation.

Implications for Autoimmune Diseases

Potential Connection to Disorders

These findings may prove valuable in considering autoimmune diseases. Conditions such as lupus are linked to certain RNAs and dead cells that trigger immune responses.

Future Research Directions

Now that researchers grasp the role of RNA glycosylation in diverting immune system attention, they can examine whether this mechanism is malfunctioning and how it might be remedied.

Source

Explore More Health, Science and Environmental Insights

Stay informed with trusted resources that expand on groundbreaking research like sugar-coated RNA and its role in immune system function.

Human Health Issues—Your go-to blog for in-depth health research, medical breakthroughs and wellness insights.

FSNews365—Daily updates on cutting-edge science, technology and innovation shaping our future.

Earth Day Harsh Reality—Eye-opening articles on environmental challenges, climate change and global sustainability.

Read the full article and explore how scientific advancements are changing the way we understand health and the environment.