A less invasive, more comprehensive test for diagnosis of Coeliac Disease
August 25, 2021. Reviewed by Victoria Simms, April 23, 2024.
Coeliac Disease: developing a less invasive test for diagnosis
Using immune repertoire profiling to test for coeliac disease
Coeliac Disease is a chronic immune disorder whereby the body's own immune system mistakenly attacks healthy tissue when triggered by gluten ingestion. This damages the surface of the small bowel (intestines), disrupting the body's ability to take in nutrients from food. For some, a delayed diagnosis may cause long term debilitating complications such as osteoporosis or bowel cancer.
Coeliac Disease is a condition that affects at least 1 in every 100 people in the UK, but some experts think this may be underestimated because milder cases may go undiagnosed or be misdiagnosed as other digestive conditions, such as irritable bowel syndrome (IBS).
By working in collaboration with researchers at the University of Cambridge led by Dr. Elizabeth Soilleux, Nonacus hopes to improve the diagnosis of this condition and to aid the development of a less invasive, more comprehensive test for the diagnosis of Coeliac Disease.
Funded by Coeliac UK and Innovate UK, this project is testing the use of immune repertoire profiling; sequencing the DNA of lymphocytes, the cells of the immune system involved in the bodies reaction to gluten. Lymphocytes are a type of immune cell that helps the body fight infection. The two main types of lymphocyte are T cells and B cells and they express cell surface receptors. In response to antigen binding (such as tumor cells, viruses or in some cases gluten) these receptors initiate an immune reaction.
People with Coeliac Disease have lymphocytes with specific DNA profiles - and this profile doesn't change, whether they have eaten gluten recently or not. The test uses Cell3™ Target technology combined with a custom designed probe panel to capture specific genomic regions for next generation sequencing. In conjunction with a bespoke computer algorithm (patent pending) it can identify patients with Coeliac Disease by predicting how likely their immune cells are to respond to gluten.
"As a company committed to developing non-invasive genetic testing products, our R&D has been focused on the areas of prenatal testing and oncology. Without the generous grant from Coeliac UK and Innovate UK we would not have considered starting this important work", says Chris Sale, CEO at Nonacus.
What stage is the project in?
In the initial phase of the project, Nonacus used a DNA Mastermix template (consisting of DNA extracted from a number of fresh blood and frozen tissue samples including lymph node, duodenum, colon and spleen and provided by Cambridge University) to develop and optimise the laboratory process by using a series of experiments to determine which set of probes and which order, gives the best results. The diversity of each sample was assessed as total number of unique CDRs an important measure of the success of the process.
The second phase of this project was to determine the minimum DNA concentration at which maximum diversity may be achieved. The third phase was to determine the performance of this double capture-based strategy on samples with a normal level of polyclonality, rather than the 'hyper-polyclonal' mastermix template.
How many samples have been processed?
To date 231 samples have been processed through this novel method which has been developed. These are a mix of control samples, duodenal biopsies from Coeliac Disease patients and blood samples from Coeliac Disease patients.
It has been shown that the method works on controls and duodenal biopsy and Nonacus have now also processed a large number of blood samples which is where the biggest benefit comes from if a minimally invasive blood test can be offered to Coeliac patients. The University of Cambridge are now analysing this data to see if there is a clear signal from the blood samples from Coeliac patients versus control patients samples.
Nonacus will also be processing another 174 duodenal biopsy samples to confirm that the method is truly robust for discerning Coeliac patients versus control (non-Coeliac patients) when analysing Duodenal biopsy. This testing method also brings benefits owing to the fact that it will not require Coeliac patients on a gluten-free diet to take gluten prior to testing and it will also provide a much clearer yes/no answer versus the current histopathology investigation of duodenal biopsies on slides.
Why has the project been delayed?
The past 16 months has been a challenging time due to the impact of the pandemic, both in terms of resourcing (staff and equipment redistribution) and procurement of lab consumables.
During this time we have been extremely busy helping out with Covid-19 testing, both in terms of manufacturing testing kits for government-approved laboratories to use and also by processing over 0.5 million samples as a government-approved testing laboratory. All of which has resulted in a delay to project delivery.
"Due to the overwhelming need to help with Covid-19 testing, our clinical service laboratory has significantly scaled its operation which is something we very much hope and look forward to using to offer the Coeliac test once developed and validated thoroughly" Chris Sale, CEO at Nonacus.
Read more about this project in our previous blog post - No gluten required.
