THYMUS-DEPENDENT EFFECTS OF A TRADITIONAL CHINESE MEDICINE, REN-SHEN-YANG-RONG-TANG (JAPANESE NAME, NINJIN-YOUEI-TO), IN AUTOIMMUNE MRL MP-LPR/LPR MICE/

Autoimmune MRL/lpr mice were i.p. treated with 200 mg/kg Ren-shen-yang -rong-tang (Japanese name: Ninjin-youei-to, NYT), a traditional Chines e herbal medicine (Japanese name: Kampo), from 8 weeks of age every 3 days before the onset of autoimmune disease. Compared to age-matched c ontrol MRL/lpr mice, the serum IL-6 concentration in NYT-treated mice was decreased, their serum IFN-gamma concentration was increased, and the proliferative responses of whole and enriched CD4(+) cells in thei r spleen and lymph nodes stimulated with ConA in vitro were restored. FAGS analysis revealed that the rate of decreased CD4(+) CD8(+) T-cell population in the thymus was decreased in MRL/lpr mice but recovered by NYT treatment. Further, adult thymectomized (ATX) MRL/lpr mice were treated with 200 mg/kg NYT similarly. NYT treatment prolonged the sur vival of sham-operated MRL/lpr mice and ameliorated their proteinuria but did not improve such autoimmune manifestations in ATX-MRL/lpr mice . These findings suggest that NYT plays an important role in the abrog ation of autoimmune-prone T cell differentiation and that the therapeu tic effect of NYT is dependent on the thymus in MRL/lpr mice. Copyrigh t (C) 1996 International Society for Immunopharmacology.