Abstract
In patients undergoing haematopoietic stem-cell transplantation (HSCT), the intestinal microbiota plays an important role in prognosis, transplant outcome, and complications such as graft-versus-host disease (GVHD). Our prior research revealed that patients undergoing HSCT substantially differed from healthy controls. In this retrospective study, we showed that administering Clostridium butyricum MIYAIRI 588 (CBM588) as a live biotherapeutic agent is associated with maintaining intestinal microbiota in the early post-HSCT period. Alpha diversity, which reflects species richness, declined considerably in patients who did not receive CBM588, whereas it remained consistent in those who received CBM588. In addition, β-diversity analysis revealed that CBM588 did not alter the gut microbiota structure at 7-21 days post-HSCT. Patients who developed GVHD showed structural changes in their microbiota from the pre-transplant period, which was noticeable on day 14 before developing GVHD. Enterococcus was significantly prevalent in patients with GVHD after HSCT, and the population of Bacteroides was maintained from the pre-HSCT period through to the post-HSCT period. Patients who received CBM588 exhibited a contrasting trend, with lower relative abundances of both genera Enterococcus and Bacteroides. These results suggest that preoperative treatment with CBM588 could potentially be beneficial in maintaining intestinal microbiota balance.