Ernst Holler, MD, University Hospital Regensburg, Regensburg, Germany, talks on the relationship between microbiota damage and graft-versus-host disease (GvHD). While the contribution of the microbiota to GvHD risk is currently unclear, a mechanism involving microbiota damage leading to impaired immunoregulation has been proposed. In addition, it has recently been shown that some specific metabolites were associated with better survival. This data suggests microbiota modulation as a promising treatment strategy, although many obstacles remain. The use of fecal microbiota transplantation (FMT) from a healthy donor to a patient with GvHD has shown improved patient outcomes, but Prof. Holler notes that it is not a curative strategy. Moreover, it is also important to tailor treatment to the individual characteristics of each patient with GvHD and give the treatment either earlier or propose GvHD prophylaxis strategies to prevent any unnecessary damage to the microbiota. However, patients are often neutropenic meaning that direct microbiota modulation could lead to bacterial translocation. Alternative microbiota modulation approaches may thus be needed. This interview took place at the 48th Annual Meeting of the European Group for Blood and Marrow Transplantation (EBMT) 2022, which was held virtually.
