[Immunosuppression of human amniotic mesenchymal cells on allogeneic peripheral blood lymphocytes].

Objective: To explore the immunoregulatory effects of human amniotic mesenchymal cells (hAMCs) on allogeneic peripheral blood lymphocytes.

Methods: The hAMCs were isolated from abandoned human amnion. Peripheral blood mononuclear lymphocytes (PBMLs) were separated from healthy donors by density gradient centrifugation. Then, PBMLs were treated with phytohemagglutinin (PHA) and different concentrations of hAMCs. Proliferation effect of PBMLs was tested using MTS assay, and production of IFN-gamma and TNF-alpha by PBMLs was detected by ELISA.

Results: hAMCs could remarkably inhibit the lymphocytes proliferation. When the ratios of hAMCs to PBMLs were 0.05: 1, 0.10 :1, 0.20: 1, the inhibitory rates of PBMLs proliferation were 16.91%, 20.83% and 28.19%, respectively. HAMCs also decreased the production of IFN-gamma and TNF-alpha by PBMLs in a dose-dependent manner (P<0.01).

Conclusions: HAMCs could inhibit the proliferation of allogeneic lymphocytes and reduce secretion of IFN-gamma and TNF-alpha, which might be one of the mechanism for prevention and remission of transplant rejection.