Faecal transplant research to stop bone marrow stem cell rejection

24 May 2021
Faecal transplant research to stop bone marrow stem cell rejection

A little poo may prove a lifesaver for children fighting cancer under a novel project.

University of Adelaide and SAHMRI researcher Dr Hannah Wardill, thanks to funding from the Leukaemia Foundation and Cancer Australia, is working on strategy to prevent children who have a bone marrow stem cell transplant ending up with organ failure because the new cells do not recognise the child’s healthy tissues and subsequently attack them.

This graft-versus-host disease (GvHD) is a major cause of mortality among transplant recipients.

Dr Wardill believes faecal microbiota transplant (FMT) may prevent the disease by introducing gut microbes from the stem cell donor, so the stem cells recognise them and do not trigger an immune attack.

FMT has been used to manage GvHD in adults, using faecal donations from a third party, however Dr Wardill’s plan is to prevent the disease in the first place by using faecal donations from the same person who donated the stem cells almost immediately after the transplant.

“We want to repopulate the microbes in the person’s gut using poo collected from their stem cell donor,” she said.

“The problem with GvHD is once it takes hold it is extremely difficult to manage, a good portion of people are resistant to first line therapy then there are limited options and high mortality rates.

“The idea is to move early to prevent it in the first place.”

Dr Wardill is testing animals to see how FMT improves the composition of gut bacteria after cancer treatment, where chemotherapy to obliterate cancer cells also wipes out good microbes in the gut.

Her laboratory work is replicating paediatric scenarios including using young mice.

At the same time she is working with adults receiving stem cell transplants at the Royal Adelaide Hospital — however in this case they are autologous FMT transplants, using the patient’s own microbe-rich faecal material collected before their chemotherapy and stored for later implant.

“These are feasibility trials in adults where they get three FMTs after their stem cell transplant,” Dr Wardill said.

“We want to see if people are able to receive three enemas after their stem cell transplant and if there is an appreciable impact on their gut bacteria and overall health.”

This trial uses the person’s own poo (autologous FMT) to reduce risks in the immune-compromised adult patients, but will give valuable pointers to the theory of using the same donor for stem cells as well as faecal material for children.

Dr Wardill says it will be some years before human clinical trials are likely to begin on her main theory and notes both the laboratory work and adult trials may end up indicating autologous faecal transplants, rather than from donors, as the way to go for children.

This story was reproduced with permission from The Advertiser.