“The human gastrointestinal tract is a highly complex ecosystem of microorganisms that exist in partnership with us, their host. These microorganisms are known as the “microbiota,” and together with the billions of genes they encode, “the microbiome.” The human gut microbiota is estimated to consist of at least 100 trillion bacteria and as many as 1000 to 1200 bacterial species. ”

The microbiota play many different roles. They participate in vitamin synthesis, fermentation of dietary carbohydrates, metabolism of bile and host hormones, and help exclude pathogenic bacteria from taking residence (like Clostridioides difficile, or “C. diff”). The microbiota also influences the development and regulation of the body’s immune system, by directly interacting with the immune system that lines the insides of the gut.

In conditions like Crohn’s disease and ulcerative colitis (inflammatory bowel disease), affected children have a very different microbiota “profile” compared to healthy individuals. Certain species are far more represented, others less so, and overall these differences are thought to affect the regulation of the body’s immune system. For autoimmune conditions like inflammatory bowel disease where medication treatments involve dampening down an overactive immune system, there may be a different approach: bringing the microbiota back to what it could have been.

Fecal microbiota transplant, or FMT, involves instilling stool bacteria from healthy, screened donors back into the intestinal tract of a patient with a condition like Crohn’s disease. There are many different ways of doing this, but some common forms involve through an enema, colonoscopy, upper endoscopy, nasogastric tube, or in pill form.

The Pai Lab has focused its research program around conducting the first, multi-centre paediatric research trials of FMT for the treatment of pediatric ulcerative colitis and Crohn’s disease (through the McMaster Pediatric FMT Research Collaboration). See above for more information about our pediatric FMT trials: PediFETCh, and PediCRaFT (currently recruiting).