Abstract:

BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) are characterized by supporting hematopoiesis, pluripotential differentiation and immunoregulation. The immunoregulatory effects are of potential importance in prevention and treatment of graft-versus-host disease (GVHD) after transplantation of allogenous hematopoietic stem cells, but the mechanism of immuno-regulation remains unknown.
OBJECTIVE: To investigate the immunoregulatory effects of human BMSCs and their conditioned medium on the secretary function of allogenous peripheral blood T lymphocytes in vitro.
METHODS: BMSCs were isolated from human bone marrow and purified by repeated adherence. Allogenous peripheral blood T lymphocytes were harvested using nylon column. The effects of BMSCs and their conditioned medium on the proliferation of phytohemagglutinin-primed T lymphocytes were observed. Interferon-γ and interleukin 4 levels were detected by ELISA.
RESULTS AND CONCLUSION: BMSCs and their conditioned medium inhibited the proliferation of phytohemagglutinin-primed T lymphocytes in a dose- and concentration-dependent manner. ELISA results showed that BMSCs and their conditioned medium inhibited the secretion of interferon-γ by T lymphocytes. BMSCs could promote the secretion of interleukin-4, but their conditioned medium did not influence the secretion of interleukin-4. These findings suggest that BMSCs and their conditioned medium inhibit the proliferation of allogenous peripheral blood T lymphocytes, and the inhibitory effects may be related to a fact that BMSCs and their conditioned medium influence T lymphocytes to secrete interferon-γ and interleukin-4.