Aussie researchers have developed a new test that can diagnose coeliac disease without the need for gluten diets or biopsies.
A world-first blood test developed by Australian researchers can accurately detect coeliac disease – offering potential to end the need for debilitating gluten challenges and invasive biopsies.
Researchers at the Walter and Eliza Hall Institute (WEHI), in collaboration with biotech company Novoviah Pharmaceuticals, say the blood test can diagnose coeliac disease in patients who are not consuming gluten.
Currently, the gold standard for diagnosing coeliac disease requires individuals to reintroduce gluten into their diet for weeks, often triggering distressing symptoms before a diagnosis can be confirmed via gastroscopy and biopsy.
This new blood test, detailed in the journal Gastroenterology, identifies gluten-specific T cells through an “in-tube” immune response—even when the patient is on a strict gluten-free diet.
The test relies on detecting the cytokine interleukin-2 (IL-2), which spikes in the blood of people with coeliac disease when gluten is introduced to their blood samples in a test tube.
The researchers used blood samples from 181 volunteers recruited via the Royal Melbourne Hospital, including 75 people with treated coeliac disease (on a gluten-free diet), 13 with active, untreated coeliac disease, 32 people with non-coeliac gluten sensitivity and 61 healthy controls.
Participant blood samples were then mixed with gluten in a test tube for a day to see if the IL-2 signal appeared.
The test detected the condition with up to 90% sensitivity and 97% specificity – even in patients following a strict gluten-free diet.
The researchers believe the new test could boost rates of diagnosis, identify patients at risk of severe reactions to gluten and detect silent coeliac disease in people who are asymptomatic.
Associate Professor Jason Tye-Din, head of WEHI’s Coeliac Research Laboratory, a gastroenterologist at the Royal Melbourne Hospital, and the corresponding author on the paper, said every approved method to diagnose coeliac disease currently required people to eat gluten.
“There are likely millions of people around the world living with undiagnosed coeliac disease simply because the path to diagnosis is difficult, and at times, debilitating,” he said.
“This new test promises to simplify and speed up accurate diagnosis, while also avoiding the suffering that comes with eating gluten for extended periods to reactivate coeliac disease.
“By eliminating the need for a gluten challenge, we’re addressing one of the biggest deterrents in current diagnostic practices.
“This test could be a game-changer, sparing thousands of people the emotional and physical toll of returning to gluten. It’s a major step towards faster, safer diagnosis.”
Coeliac disease is one of the most common autoimmune illnesses in Australia, caused by an immune reaction to the gluten protein found in wheat, rye and barley. More than 350,000 Australians currently live with the condition.
While early diagnosis is critical to minimising long-term complications of the disease, up to 80% of cases around the world remain undiagnosed, according to the researchers.
The diagnostic process can be confusing for patients and non-specialist doctors, as the reduction in symptoms from a gluten-free diet is not always a marker of coeliac disease.
Current coeliac testing methods – serology blood tests or gastroscopy with intestinal biopsy – do not work reliably for those on a gluten-free diet and require regular gluten consumption to be effective. As a result, many people are deterred from seeking a definite diagnosis because they do not want to consume gluten and be sick.
The research began in 2019 when WEHI researchers, working with Dr Robert Anderson, (who went on to co-found Novoviah), president of the International Society for the Study of Coeliac Disease, made the unexpected discovery that the immune marker interleukin 2 (IL-2) spiked in the bloodstream of people with coeliac disease shortly after they ate gluten.
Dr Anderson, also a gastroenterologist at Mackay Base Hospital, said the landmark study reflected the WEHI team’s global role as leaders in translational immunology.
“I have been delighted to have a close and exceptionally productive collaboration with Professor Tye-Din that launched innovative therapies and now diagnostics harnessing the gluten-specific T cells we obsessively characterised in studies over the past 25 years,” he said.
While the IL-2 detection technology is not yet standard in pathology labs, the team is working to validate the test across broader populations and pave the way for clinical implementation.
For one of the authors, PhD researcher Olivia Moscatelli, the discovery has been particularly welcome, having been diagnosed with coeliac disease at the age of 18.
“This breakthrough is deeply personal as it could spare others from the gruelling diagnostic process I had to endure. Knowing I’ve played a role in this achievement is a powerful, full-circle moment,” she said.
“This represents a promising new tool to support diagnosis, especially for people who can’t be diagnosed with the currently available methods.
“We also found the strength of the IL-2 signal correlated with the severity of a patient’s symptoms, allowing us to predict how severely a person with coeliac disease might react to gluten, without them actually having to eat it.
“The test’s performance in individuals with other autoimmune conditions in addition to coeliac disease, such as type 1 diabetes or Hashimoto’s thyroiditis, is also unmatched.
“Some diagnostic tests give false positives in the presence of other autoimmune diseases, but this was not an issue for this test. This is largely because the technology we use is highly sensitive and can detect the IL-2 signal at exceptionally low levels. It’s like the equivalent of being able to detect a single grain of sand in a swimming pool.”
The research is supported by Coeliac Australia, Novoviah Pharmaceuticals (who provided the proprietary test for this study), Beck Family Foundation, Butterfield Family, and the Veith Foundation.
