‘Super donors’ may be pivotal to the future of fecal transplants
Fecal microbiota transplantation donors who can successfully transfer important bacteria to recipients could be the future of treating diseases like inflammatory bowel disease and irritable bowel syndrome, according to research published in Frontiers in Cellular and Infection Microbiology.
Justin M.O. Sullivan, BSc (Hons), PhD, of the University of Auckland, in New Zealand, said in a press release that the success of FMT in treating Clostridium difficile infection has led to expanded research into other diseases.
“The last two decades have seen a growing list of medical conditions associated with changes in the microbiome — bacteria, viruses and fungi, especially in the gut,” he said. “In fact, we know already that changes to the gut microbiome can contribute to disease, based on studies in germ-free mice as well as clinical improvement in human patients following restoration of the gut microbiome by transplanting stool from a healthy donor.”
Although studies of FMT in other diseases have produced less evidence of success, results among small groups of donors led Sullivan and colleagues to search for what they called “super poopers,” whose stool seems more likely to influence a recipient’s gut microbiota. They explored the literature for evidence of these super donors and to explore the concept of keystone species of bacteria as predictors of FMT success.
The authors wrote that the study of FMT in IBD made up a large portion of the research, but also found trials that focused on IBS, constipation and allergic colitis, as well as liver, blood, and metabolic and neurological conditions. They found that the results of these studies were highly variable and report an average success of FMT of about 20% compared with FMT’s 90% success rate in recurrent diarrheal infections.
Sullivan and colleagues found that “super donors” typically had a greater number of bacterial species than other donors. They were also more successful in transferring keystone species to recipients.
In conditions like IBD and metabolic syndrome, they wrote that transferring butyrate-producing taxa appeared important for therapeutic restoration. In IBS, donors with high abundance of Bifidobacterium were the most effective.
Sullivan and colleagues wrote that donors and keystone species are just one part of the puzzle. They called for future studies to include information on recipients’ genetic background, diet and other factors that could impact the efficacy of FMT.
“Some fecal transplant failures may be attributable to the gut’s immune response to transplanted microbes, possibly stemming from an underlying genetic difference between the donor and the recipient,” they wrote. “Supporting the transplanted microbiome through diet could also improve success. It has been shown that a rapid change in diet, such as a switch from an animal-based to an exclusively plant-based diet, can alter the composition of the gut microbiota within 24 hours.” – by Alex Young
Disclosures: The authors report no relevant financial disclosures.