Abstract: Sophora moorcroftiana is the specific plant in Tibet and gets little development since grows in the remote place.In order to research its medicinal value,we firstly extract Sophora moorcroftiana polysaccharides (SMP) and investigate the effects on CD4+CD25+ regulatory T cells (CD4+CD25+Treg) cells and Th17 cells in immunosuppressed mice.SMP was extracted from branch of Sophora moorcroftiana after water extraction and alcohol precipitation.The immunosuppressed mice induced by cyclophosphamide were treated with SMP,then the ratio of CD4+T cells and CD4+CD25+Treg cells were analyzed by flow cytometry and the serum interleukin-17 (IL-17) were detected by enzyme-linked immunosorbent assay (ELISA).The results showed that each dose SMP increased the frequency of CD4+CD25+Treg in spleen and decreased the serum IL-17 production.In conclusion,SMP plays a role in immunosuppression by up-regulating Treg and suppressing IL-17 production.

Key words: Sophora moorcroftiana, Plant polysaccharide, Regulatory T cells, Interleukin-17