Immunomodulatory study of umbilical cord mesenchymal stem cells on allogeneic T lymphocytes proliferation

Objective:To study the immunomodulatory functions of umbilical cord mesenchymal stem cells in vitro and its mechanisms.Methods:UC-MSC were separated from umbilical cord,the purity of MSC was analyzed by flow cytometry; The proliferation of allogeneic T lymphocytes was measured by Brdu method;The impact on the T cells subset and cytokine secretion were measured.Results:UC-MSCs could suppress proliferation of umbilical cord blood lymphocytes stimulated by mitogen in dose-dependent manner.CD8+suppopulation was decreased (P0.01),and CD4+suppopulation was changed midly(P0.01). ELISA showed that the secretion of IFN-γ was downregulated, and IL-4 was upregulated(P0.01). Conclusion:UC-MSC can supress T cells proliferation,affect T cell subsets and cytokine secretion.The results indicate that UC-MSCs might negatively modulate T lymphocyte-mediated immunity,prevent and treat GVHD in allogeneic stem cells transplantation.