The effect of glycyrrhizin on maturation and T cell stimulating activity of dendritic cells.

Glycyrrhizin (GL), a main component of the plant Glycyrrhiza glabra has shown various immunomodulatory activities that can interfere with immune responses by targeting the dendritic cells (DCs). In this study, the effects of GL on the maturation and function of mouse splenic DCs was investigated. The results of flow cytometry analysis showed that GL was able to up-regulate the expression of CD40, CD86 and MHC-ІІ maturation markers on DCs. This component increased the production of IL-12 by these cells. The capacity of treated DCs to stimulate allogenic T cells and secretion of cytokines was examined in mixed lymphocyte reaction. DCs treated with GL enhanced proliferation of allogenic T cells along with the production of IFN-γ and IL-10 cytokines and reduced IL-4 production. These data indicated that GL has the capacity to up-regulate allostimulatory activity of professional antigen presenting DCs and conduct immune responses toward a T helper 1 response.