Immunosuppressive effect of ethanol extract of Artemisia annua on specific antibody and cellular responses of mice against ovalbumin.

Artemisia annua has been widely used to treat autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis in traditional Chinese medicine. In this study, the ethanol extract of A. annua (EEAA) was evaluated for the immunosuppressive potentials on mice splenocyte proliferation in vitro, and the specific antibody and cellular immune responses in the ovalbumin (OVA)-immunized mice. EEAA significantly suppressed concanavalin A (Con A)- and lipopolysaccharide (LPS)-stimulated splenocyte proliferation in vitro in a concentration-dependent manner. EEAA also significantly suppressed Con A-, LPS- and OVA-induced splenocyte proliferation in the OVA-immunized mice in a dose-dependent manner. Meanwhile, the OVA-specific serum IgG, IgG1 and IgG2b antibody levels in the OVA-immunized mice were markedly reduced by EEAA. The results suggest that EEAA could suppress the cellular and humoral response in mice. This study provided evidence to understand the therapeutic effects of A. annua for treatment of some autoimmune diseases and an immunosuppressive natural products to further researches to be developed as immunosuppressant.