Echinacea purpurea promotes maturation of dendritic cells in vitro

In this study, we analysed the effect of Echinacea purpurea on the maturation of monocyte derived dendritic cells (mDC) of healthy human donors. Echinacea p. was either used as a single maturation stimulus or in addition to various concentrations of IL-1, TNF-, and IL-6. Used as a single stimulus, Echinacea p. induced an upregulation of DC markers such as CD83 and CD80 as well as the expression of the chemokine receptor CCR7. Furthermore, in combination with IL-1, TNF-, and IL-6 Echinacea p. showed a clear additive effect on DC maturation. This was accompanied by an increase in PGE2 in supernatants of mDC cultures. Our study implies that Echinacea p. is able to trigger mDC to enhance their antigen presenting functions and migration capacity which could result in a more efficient activation of resting T-cells in the lymphoid compartment.