Transplanted mesenchymal stem cells can inhibit the three developmental stages of murine acute graft-versus-host disease.

BACKGROUND Recent data have demonstrated that mesenchymal stem cells (MSCs) have potent immune regulation capacity in vitro, enhancing their therapeutic appeal for their utilisation in the management of acute graft-versus-host disease (aGvHD). However, their immunoregulatory activity in vivo is largely unknown. MATERIALS AND METHODS Using murine compact bone-derived MSCs in an aGvHD model, the phenotypic status of splenocytes of aGvHD and aGvHD+MSC groups of mice were examined by flow cytometry. RESULTS MSC infusion decreased the expression of MHC-II and CD69 molecules on splenic CD11b+ cells of aGvHD mice, which resulted in decreased maturation of antigen-presenting cells. Moreover, the down-regulated ratio of CD3+CD69+ to CD3+ cells, leading to restrained early activation and effector T-cell formation, resulted in the enhancement of the absolute and relative number of splenic CD3+ cells by MSCs co-transfer. CONCLUSION This study demonstrated that MSCs can inhibit the three developmental stages of aGvHD.