title: Icaritin inhibits T cell activation and prolongs skin allograft survival in mice.
abstract: Icaritin is a native compound from Epimedium Genus, a traditional Chinese herbal medicine which is effective in treating asthma, autoimmune diseases and viral infections. In the present paper, the immunosuppressive effects of icaritin were found through in vitro and in vivo studies. Icaritin could dose-dependently inhibit murine CD4(+) T cells proliferation stimulated with mitogens or specific antigen ovabumin (OVA). Icaritin at 0.25-25μM could down-regulate T cell activation marker CD25 expression and inhibit IL-2 production. It could also reduce the Th1 cytokine IFN-γ production significantly if the T cells were activated by ConA or anti-CD3; while the inhibition of IL-4 secretion was only seen on anti-CD3 activated T cells treated with low concentrations of icaritin. In vivo study showed that treatment of icaritin at 10mg/kg/day on mice could suppress the immune response with prolonged allograft skin survival. Further study demonstrated that it reduced the alloantigen-induced splenocytes proliferation and Th1/Th2 cytokines. It could also increase NF-AT luciferase activity in Jurkat-NF-AT-luc T cells. The above results suggested that icaritin might be used to treat Th1 dominated immune diseases by interfering T cells activation with mechanism different to CsA.
authors.affiliation: School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Li
authors.forename: Yiping
authors.initials: Y
authors.lastname: Hu
authors.forename: Longgang
authors.initials: L
authors.lastname: He
authors.forename: Song
authors.initials: S
authors.lastname: Wang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhou
authors.forename: Shuwen
authors.initials: S
authors.lastname: Liu
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage / Q000302:isolation & purification / Q000627:therapeutic use*; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage / Q000302:isolation & purification / Q000627:therapeutic use*; D006085:Graft Survival / Q000187:drug effects*; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000627:therapeutic use*; D007376:Interleukin-2 / Q000037:antagonists & inhibitors; D053645:Interleukin-2 Receptor alpha Subunit / Q000037:antagonists & inhibitors; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D016038:Skin Transplantation; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D018417:Th1 Cells / Q000187:drug effects / Q000276:immunology; D014184:Transplantation, Homologous
chemical_list: D004365:Drugs, Chinese Herbal; D005419:Flavonoids; C508018:Il2ra protein, mouse; D007166:Immunosuppressive Agents; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; C499403:icaritin