Scientists
have identified biomarkers that could form the basis of the world's first blood
test for celiac disease. They discovered that exposure to gluten in people with
celiac disease causes a rise in certain inflammatory molecules in the
bloodstream that correlates with common symptoms.
The current
method for diagnosing celiac disease can
take weeks or months. It involves people having to consume gluten and experience
the very unpleasant side effects for all of that time. A blood test could cut
that time to hours.
The
biotechnology firm ImmusanT Inc., of Cambridge, MA, led the international team
behind the recent discovery, which features in the journal Science Advances.
"For
the first time," says co-senior study author Dr. Robert P. Anderson, Chief
Scientific Officer of ImmusanT, "we have described the inflammatory
reaction that patients with celiac disease experience in the immediate hours
after they are exposed to gluten."
Dr. Anderson
suggests that the findings could also lead to methods that help to spot people
without celiac disease — but who have similar symptoms — and guide them to more
suitable treatments.
Celiac
disease is a lifelong condition that affects around 1% of people in Western countries,
according to figures from the World Gastroenterology Organisation.
Gluten
triggers autoimmune attack on gut
People with
celiac disease have an adverse immune reaction to gluten, a protein that is
present in wheat, rye, barley, and foods that contain them, such as pasta and
bread.
The presence
of gluten in the gut causes the immune system to attack the small intestine.
The attack damages the digestive system and reduces its ability to absorb
nutrients, causing a range of symptoms.
The symptoms
of celiac disease include bloating, diarrhea,
vomiting, the presence of too much fat in the stools (steatorrhea), anemia due
to iron deficiency, and weight loss. In children, it can also result in failure
to thrive.
People
with celiac disease have to follow a gluten free diet for the rest of their
lives.
Experts
suggest that the number of people with diagnosed celiac disease does not
reflect the true prevalence of the condition. They believe that many more
people remain undiagnosed.
'Increase
in inflammatory molecules'
Dr. Anderson
and his colleagues discovered that injecting gluten peptides into people with
celiac disease led to symptoms, such as nausea and vomiting, as well as higher
levels of certain immune system molecules. Peptides are short chains of amino
acids.
"The
unpleasant symptoms associated with the disease are linked to an increase in
inflammatory molecules in the bloodstream, such as interleukin-2 (IL-2),
produced by T cells of the immune system," he explains.
"This
response is similar to what happens when an infection is present; however, for
people with coeliac disease, gluten is the trigger," he adds.
Scientists at
ImmusanT identified the inflammatory molecules while running a trial of a
potential celiac treatment. They saw how the injection of gluten peptides led
to symptoms that correlated with raised levels of the blood markers.
In further
tests, the researchers also showed that when people with celiac disease consumed
gluten, they experienced the same rise in IL-2.
Work on using
the findings to develop a simple blood test for celiac disease is already
underway, says study author Dr. Jason A. Tye-Din, an associate professor and
head of celiac research at the Walter and Eliza Hall Institute in Australia.
Dr. Tye-Din,
who is also a gastroenterologist at The Royal Melbourne Hospital, adds that
"[f]or the many people following a gluten free diet without a formal
diagnosis of celiac disease, all that might be required is a blood test before,
and 4 hours after, a small meal of gluten."
"This would be a
dramatic improvement on the current approach, which requires people to actively
consume gluten for at least several weeks before undergoing an invasive
procedure to sample the small intestine."
Dr. Jason A. Tye-Din
No comments:
Post a Comment