Allogeneic stem cell therapy could become a go-to treatment option for many hematological diseases, like Leukaemia, myeloma, and lymphoma. These conditions are usually caused due to damage in the bone marrow, making it no longer possible to produce healthy blood cells. However, the success of the treatment has been limited to the high mortality rate associated with acute graft-versus-host disease (GvHD). 

There are several pieces of evidence available that show several factors, such as the use of antibiotics and malnutrition, can alter the microbes in the gut and have a significant impact on the outcome of allogeneic stem cell therapy recovery.

Literature has indicated that there could be a correlation between the gut microbiota and the success of the transplant. A leading study published in Nature Journal set out with the aim to prove that there is indeed an association between gut microbiota and stem cell transplantation success. The study aimed to decipher how these gut microbiota boost the success of stem cell transplantation.

The study found that certain bacteria belonging to the Oscillospiraceae and Lachnospiraceae families that when present in the gut with their associated bacteriophages can help recovery post allogeneic stem cell treatment. Another group of bacteria found in the gut is the Roseburia family, which helps maintain immunity and exerts anti-inflammatory properties. It is not just bacteria, the group found a large repertoire of fungi. Although, unlike bacteria the fungus identified in the study shows a negative impact on the GvHD.

The group analyzed the metabolic profile to understand the underlying mechanism of how microbiota can have such a large impact on the success of stem cell transplants. Researchers analyzed stool samples from a group of patients getting a stem cell transplant and found that patients with a wider range of microbes had better results lower transplant-related mortality and less relapse. They also found that antibiotic use disrupts the balance of the beneficial microbes and their metabolites, potentially leading to worse outcomes.

Utilizing this study, researchers are innovative strategies, such as the development of synthetic bacteria-bacteriophage consortia to improve transplant outcomes. This approach aims to harness the potential of engineered microbial communities to produce immunomodulatory molecules (IMMs). These  IMMs can be optimally chosen with the aim of improving the efficacy of stem cell transplants.

Additionally, recognizing the crucial role of beneficial bacteria and IMMs in overall health, there’s a push to modify antibiotic use to minimize disruptions to these essential elements. This discovery could revolutionize stem cell transplants and potentially other cell therapies too! If a patient is considered at risk, they could be treated using the helpful metabolite cocktails from donors that have been previously validated for robust metabolite production. The study opens a new avenue for stem cell transplantation and microbiome studies in other cell therapies.