Researchers from the University of Virginia School of Medicine have discovered that the presence of IL-25, an important agent of the immune system, improved the success of faecal transplant in combatting C. difficile infections. The findings were published I the paper, ‘Microbiota Transplantation Increases Colonic IL-25 and Dampens Tissue Inflammation in Patients with Recurrent Clostridioides difficile’, in the scientific journal mSphere.
C. difficile infection causes life-threatening diarrhoea and it often takes hold in patients in hospitals and nursing homes as a result of long-term antibiotic use. Doctors have known that faecal transplants can improve C. difficile outcomes, but they have not fully understood why.
"Even though we know that faecal microbiota transplants can treat recurrent C. difficile infection, we don't know exactly why some microbe combinations work better than others or why the same combinations can have different effects on different people. We believe that this variability stems from each person's immune system being unique. That is why it is important for us to find out what immune markers change in patients where faecal microbiota transplantation was successful in preventing C. difficile re-infections," said researcher, Dr Ning-Jiun Jan, UVA's Division of Infectious Disease and International Health. "Finding that a specific immune signalling molecule, IL-25, was increased in successful faecal microbiota transplantations indicated that maybe IL-25 can be used as an adjunctive therapy for treating C. difficile infection."
The new findings come from the lab of UVA's Dr Chelsea Marie, where Jan is a research scientist. To better understand the effects of faecal transplants on patients with C. difficile, Marie, Jan and their collaborators looked at blood and colon-tissue samples collected from patients at the time of their transplants and then again 60 days later.
The researchers found that the transplants increased the presence of IL-25, an important agent of the immune system, in the patients' colons. The cytokine serves as a vital link in the communication chain that controls our body's immune responses. This increase in IL-25 was accompanied by a decrease in damaging tissue inflammation.
The transplants also increased the diversity of the microbes that naturally live in our colons, the researchers found. These microorganisms have increasingly been appreciated as essential for good health.
The researchers concluded that the changes triggered by faecal transplants, including beneficial changes in the activity of certain genes, bolster the ability of the immune system to battle recurrent C. difficile infections. This ultimately helps patients heal.
The scientists believe that doctors may be able to enhance the benefits of faecal transplants by using other means to promote IL-25 in patients battling recurrent C. difficile.
"In the future it may be possible to combine faecal microbiota transplants with cytokine-based therapies to increase the success rate of treatment," explained Jan. "There is a lot of interplay between our immune system and our intestinal microbes, and it's exciting that understanding their relationship is helping us find new therapies."
To access this paper, please click here