Restoring the Microbiota After Stem Cell Transplantation with Fecal / Stool Transplantation

In a small group of patients with hematological cancers, autologous fecal microbiota transplantation (transplantation of one's own stool microbiota) was shown to restore a patient's gut microbiota after microbiota-depleting antibiotic treatment administered during allogeneic hematopoietic stem cell transplantation.

Allogeneic stem cell transplantation, particularly leukemia and lymphoma , is a frequently preferred treatment for hematological cancers (originating in the blood and bone marrow).

What is the microbiota?

Each human consists of approximately more than 60 trillion cells. About 30 trillion are human cells. Approximately 30 trillion are organisms living in the human body, microorganisms. These harmless microorganisms, which may be viruses, bacteria or fungi, are called the microbiome / microbiota / flora and are most abundant in the intestine and skin. We continue to live with these beneficial microorganisms in a mutually beneficial relationship.

What is fecal microbiota transplantation?

Known medically as fecal transplantation , the procedure called stool transplantation has frequently been heard about in recent years. Its purpose is supporting the intestine with a healthy microbiota. Fecal microbiota transplantation involves administering a solution of fecal material from a donor into a recipient's intestinal system to directly change the recipient's gut microbial composition and provide a health benefit (in the study discussed here, the patient's stool collected before cancer treatment is returned after treatment, meaning the donor and recipient are the same person; therefore it is called autologous transplantation ).

Fecal microbiota transplantation has been used successfully to treat the recurrent form of a serious intestinal disease, Clostridium difficile infection. There are preliminary indications of therapeutic potential for other conditions such as inflammatory bowel disease, obesity, metabolic syndrome and functional gastrointestinal disorders. However, fecal transplantation has also become a medical practice that is widely misunderstood and attributed miraculous significance by some ; for example, despite the absence of scientific evidence, it is persistently recommended for treating the neurodevelopmental condition autism .

Antibiotics are generally given during allogeneic stem cell transplantation to deplete/reset the gut microbiota, because the immune system is also reset during treatment and these microorganisms risk causing opportunistic infections. However, administering these antibiotics puts the patient at risk particularly of subsequent intestinal infections, because the flora also protects against infections. In other words, gut flora can be a double-edged sword depending on the circumstances. The beneficial bacteria's greater diversity corresponds to healthier flora.

Study details

The study findings were published on 26 September 2018 in Science Translational Medicine'.

The research is based on an analysis of data from an ongoing randomized, open-label, phase-2 clinical study at Memorial Sloan Kettering Cancer Center, covering 25 enrolled patients undergoing allogeneic stem cell transplantation.

Patients were divided into two arms; 14 received autologous (their own) fecal microbiota transplantation (auto-FMT), while 11 were assigned to the control group. Stool samples were collected at specific time points to assess changes in microbial diversity and composition.

The gut microbiota of patients receiving auto-FMT rapidly regained the microbial diversity and composition present before antibiotic treatment and allogeneic stem cell transplantation. However, patients in the control group did not regain their pretreatment gut microbial composition.

The study authors described the significance of the study as follows: "These results show that banking fecal/stool samples for patients whose microbiota will be depleted by antibiotic use during allogeneic stem cell transplantation has the potential to improve intestinal and general health after treatment." They expressed it in these words.

Researchers are continuing to follow existing and newly diagnosed patients to determine whether autologous fecal microbiota transplantation improves clinical outcomes.

Related Topics:

- What Is Gut Flora (Microbiota, Microbiome)? What Is Its Relationship with Colorectal Cancer?

- The Protective Benefits of Skin Bacteria Against Skin Cancer

- The Mediterranean Diet Increases Good Gut Bacteria!

- Salt Kills Beneficial Gut Bacteria and Feeds Harmful Ones