In a first-of-its-kind study, Australian researchers are trialing the immune-boosting powers of human waste to treat cancer survivors with a common chronic post-operative illness.
"Graft-Versus-Host Disease (GVHD) is a common complication of bone-marrow transplant," Andrea Henden, who is leading the study, told Newsweek.
Bone-marrow transplants are used to treat patients with certain forms of cancer and other blood diseases. Bone marrow is the tissue where blood cells are made, so replacing this tissue can restore a healthy cell population in the patient's blood.
However, because bone marrow is responsible for the production of white blood cells—the body's biological SWAT squad—the transplantation effectively introduces a whole new immune system into the host. Sometimes, this immune system does not recognize the cells of its new host, and so will start attacking the patient's own healthy cells. This is what happens in GVHD.
"When [GVHD] occurs soon after bone-marrow transplant. it is termed 'acute' and can affect the gut, lungs, liver and skin," Henden said. She is a researcher with the QIMR Berghofer Medical Research Institute and cancer specialist at the Royal Brisbane and Women's Hospital in Australia. "In our institution, this happens between 25 and 30 percent of the time.
"When GVHD happens after 100 days [following the operation], it is termed chronic and can affect up to 70 percent of bone-marrow transplant recipients. It can affect any organ in the body," Henden added.
Conventional treatments for GVHD usually center around immunosuppressing drugs. However, these leave the patients vulnerable to other diseases, and often fail to stop the disease.
The factors influencing a patient's susceptibility to GVHD are unclear. However, recent studies have shown a clear connection between the disease and the state of the resident microbes that live in the patient's gut.
"The chemotherapy and antibiotics that we give as part of a bone-marrow transplant causes a very abnormal, or dysbiotic, microbiome," Henden said. "It is believed that this dysbiosis contributes to GVHD. Fecal microbial transplant, or FMT, is a way to try to restore a more normal microbiome."
Your body is home to trillions of microorganisms, the majority of which can be found in your gut. This gut microbiome has been implicated in everything from digestion to depression, but it also plays a vital role in supporting your immune system.
Our microbiomes are vulnerable to harsh treatments, like antibiotics and chemotherapy. It can be difficult to build them back up to normal, healthy levels after they have been depleted.
One way to restore a healthy population of gut microbes is to transfer them from one person to another. This is done via a human-waste transplant, more formally known as an FMT.
"By restoring a more healthy and diverse gut microbiome, FMT is thought to promote microbes with protective properties and push the balance away from a predominance of harmful microbes," Henden said. "It may also restore the barrier function of the gut which is also damaged by chemotherapy, but the exact mechanism by which it is beneficial is still to be proven."
In the present trial, donors will be selected from a team of volunteers, following a screening procedure similar to procedures used for blood donation. "After testing and processing, the FMT is administered via a naso-duodenal tube, which is a tube that passes through the nose, gullet and stomach and into the small gut," Henden said.
This is not the first time FMT has been used in seriously ill patients. It is sometimes used to treat patients with recurring Clostridium difficile infections. This is a gut infection that can occur after antibiotic treatment and cause severe stomach complications and colon inflammation.
We are still in the early phases of microbiome research, and the applications of this treatment procedure are only just beginning to be understood. "There is emerging evidence that microbiome and dysbiosis is important in treatment responses in other cancer immunotherapies. It may also be useful in other immune-driven gut diseases like inflammatory bowel disease," Henden said.
The trial has been funded by the Royal Brisbane and Women's Hospital Foundation and run in collaboration with the Australian Red Cross Lifeblood Microbiome Project. It will also aim to hone in on the specific microbial species responsible for improving symptoms of GVHD to produce more effective, targeted treatments.
Uncommon Knowledge
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Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.
About the writer
Pandora Dewan is a Senior Science Reporter at Newsweek based in London, UK. Her focus is reporting on science, health ... Read more
