ABSTRACT
Objective: To investigate the effects of ginsenoside Rb1 on activation and proliferation of murine T lymphocytes in vitro and to elucidate the mechanism of the immunosuppressive effect of ginsenoside Rb1. Methods: Cell suspensions were prepared from murine lymph nodes. T lymphocytes were treated with different concentrations of ginsenoside Rb1 and stimulated with polyclonal activator concanavalin (ConA). Fluorescence conjugated monoclonal antibodies and flow cytometry were used to detect the expression of CD3/CD69 and CD4/CD25. After the staining with CFDA-SE, T lymphocytes were stimulated with polyclonal activator ConA. The proliferation of T lymphocytes, after stimulated by ConA, was detected using the method of MTT. The distribution of the cell apoptosis was analyzed by staining both DIOC and PI. Results: In a dose-dependent manner, ginsenoside Rb1 (5, 10, and 20 μmol/L) could significantly inhibit T lymphocytes activation index (P<0.01) stimulated by ConA and proliferation index (P<0.05) stimulated by ConA. Ginsenoside Rb1 could also reduce the apoptosis of T lymphocytes stimulated by H2O2. Conclusion: Ginsenoside Rb1 can effectively inhibit the activation and proliferation of murine T lymphocytes, and ginsenoside Rb1 is a potential effective immunoinhibitory agent.