A new study from Sinai Health has found that a simple blood test could predict Crohn’s disease years before any symptoms appear.
This breakthrough opens the door to early diagnosis and, potentially, prevention of the disease. The test measures the body’s immune response to a protein called flagellin, which is found on bacteria that live in the gut.
Led by Dr. Ken Croitoru from the Lunenfeld-Tanenbaum Research Institute, and supported by Dr. Sun-Ho Lee and Dr. Richard Wu, the research team discovered that people who eventually develop Crohn’s disease often have elevated immune responses to flagellin long before they feel sick.
Their findings, published in Clinical Gastroenterology and Hepatology, show that this reaction may be one of the first steps in the disease process.
Crohn’s disease is a long-lasting condition that causes inflammation in the digestive system. It can lead to serious digestive symptoms, pain, fatigue, and poor quality of life. The number of people affected is rising fast, especially in children. In Canada alone, nearly half a million people are expected to be living with inflammatory bowel disease (IBD) by 2035.
Dr. Croitoru believes that understanding the early changes in the immune system could help prevent Crohn’s from developing in the first place. “Even though we have powerful treatments today, we’re still not curing anyone.
We need better strategies,” he said. Dr. Croitoru holds the Canada Research Chair in Inflammatory Bowel Diseases and is part of Mount Sinai Hospital’s Center for Inflammatory Bowel Disease.
The study is part of the ongoing GEM Project, a large international research effort led by Dr. Croitoru. Since 2008, the project has tracked more than 5,000 healthy people who have a close family member with Crohn’s disease.
Researchers collect genetic, biological, and environmental data from these participants to understand how the disease starts. So far, 130 participants have developed Crohn’s, giving scientists a rare chance to study the early stages before symptoms begin.
In earlier work, the team showed that people who later developed Crohn’s had an abnormal immune response against gut bacteria. Normally, the bacteria in our gut help keep us healthy. But in Crohn’s disease, the immune system starts to attack them as if they were harmful invaders.
In the new study, the researchers worked with a team from the University of Alabama, where Dr. Charles Elson had created a test to detect antibodies against flagellin. These antibodies are more common in people with Crohn’s. The Sinai team asked: could this immune reaction also be found in healthy people who are at risk but not yet sick?
To find out, they studied blood samples from 381 healthy people with a family history of Crohn’s. Over time, 77 of them developed the disease. Of those, 28 people—more than one-third—already had elevated flagellin antibodies in their blood years before diagnosis. The reaction was strongest in siblings, suggesting a link with shared environment and lifestyle.
The immune response also matched signs of gut inflammation and problems with the gut lining—both early features of Crohn’s disease. On average, it took about two and a half years from the blood sample to the time the person was diagnosed.
Dr. Lee explained that the immune system was reacting to a conserved part of the flagellin protein, raising the possibility of designing a vaccine that targets this part. Such a vaccine could help prevent Crohn’s in people who are at high risk.
This research could be a game-changer in how Crohn’s disease is diagnosed and managed. While more studies are needed, the ability to spot the disease years before symptoms start could lead to earlier care, better outcomes, and maybe even prevention.
If you care about gut health, please read studies about how probiotics can protect gut health, and Mycoprotein in diet may reduce risk of bowel cancer and improve gut health.
For more health information, please see recent studies about how food additives could affect gut health, and the best foods for gut health.
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