title: Baicalin, a natural compound, promotes regulatory T cell differentiation.
abstract: BACKGROUND
  CD4(+)CD25(+)Foxp3(+) regulatory T (T(reg)) cells inhibit autoimmunity and protect against tissue injury. The development of these T(reg) cells is controlled by the regulator protein Foxp3, which can be enhanced by the in vitro activation of Foxp3 in the presence of transforming growth factor-beta. However, little is known about alternative methods, such as the use of natural products, for controlling Foxp3-mediated T(reg) cell differentiation.
  
  
  METHODS
  HEK 293 T cells were transfected with Foxp3 expression plasmid, and then treated with different compounds, Foxp3 mRNA expression was determined by real-time RT-PCR. CD4(+)CD25(-)T cells were stimulated with Baicalin, Foxp3 protein expression were analyzed by flow cytometry and confocal microscopy, the regulatory function of T cells stimulated with Baicalin was detected by the carboxyfluorescien succinimidyl ester.
  
  
  RESULTS
  We demonstrated that Baicalin, a compound isolated from the Chinese herb Huangqin, induced Foxp3 protein expression in cultured T cells, promoted T(reg) cell differentiation and regulatory activity. Our data also indicated that Baicalin restored Foxp3 expression following its initial interleukin-6-mediated inhibition and induced Foxp3 expression in vitro.
  
  
  CONCLUSIONS
  These data suggest that Baicalin may promote T(reg) cell differentiation and regulatory activity and may serve as a promising natural immunosuppressive compound for treating autoimmune inflammatory diseases.
authors.affiliation: Department of Dermatology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Yang
authors.forename: Xue
authors.initials: X
authors.lastname: Yang
authors.forename: Ming
authors.initials: M
authors.lastname: Li
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology*; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000276:immunology; D057809:HEK293 Cells; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology; D031363:Scutellaria / Q000737:chemistry*; D050378:T-Lymphocytes, Regulatory / Q000166:cytology* / Q000187:drug effects
chemical_list: D004365:Drugs, Chinese Herbal; C418974:FOXP3 protein, human; D005419:Flavonoids; D051858:Forkhead Transcription Factors; D015850:Interleukin-6; C038044:baicalin