Artesunate inhibits proliferation of naïve CD4+ T cells but enhances function of effector T cells

Artesunate is an artemisinin derivative from Artemisia annua and is being applied as a first-line drug for malaria treatment. In addition to anti-malarial effects, anti-cancer, anti-viral, and anti-inflammatory activities have been reported for artemisinin derivatives. In this study, we investigated the effects of artesunate on naïve T cell activation and Th1/Th2 differentiation. Artesunate inhibited the proliferation of CD4+ T cells and the production of IL-2, T cell growth factor. Moreover, artesunate reduced the expression of cell surface protein CD25 (IL-2 receptor alpha chain) and CD69 on CD4+ T cells. Artesunate showed inhibitory effects on naïve T cell activation but artesunate increased the production of IFN-γ and IL-4 under Th1 and Th2 skewed condition respectively. Therefore, these results suggest that artesunate has a negative mitogenic effect on CD4+ T cells but reinforces the function of effector T cells.