Effect of mucosal-associated invariant T cells on gut acute graft-versus-host disease after hematopoietic stem cell transplantation

Abstract Objective:Gut acute graft-versus-host disease (aGVHD) is one of serious complication after hematopoietic stem cell transplantation (HSCT). Mucosal-associated invariant T (MAIT) cells are a group of innate T cells that are enriched in the gut. Currently, there is limited research on the role and function of MAIT cells in the development of aGVHD in humans.Our study aim to investigate the effect of MAIT cells on the occurrence of gut aGVHD after HSCT in children, and to developing a new clinical prevention and treatment strategy for gut aGVHD. Methods: We collected peripheral blood(PB)samples from 81 patients 30 days after HSCT. The content of MAIT cells was detected via flow cytometry to investigate the relationship between MAIT cells and gut aGVHD occurrence in children. Results: The count of MAIT cells in the PB of children with gut aGVHD was notably lower than that in those without aGVHD and other types of aGVHD. Conclusion: The PB of patients who develop gut aGVHD after HSCT demonstrates a reduction in MAIT cells. This reduction may be associated with delayed immune reconstitution and a higher risk of gut aGVHD post-transplantation,as well as a potential impact on the host's capacity to defend against intestinal infections.