title: Effect of Kidney-replenishing herb on the indoleamine 2,3-dioxygenase of human syncytiotrophoblasts cultured in vitro and the balance of helper T-cell cytokines.
abstract: BACKGROUND
  There is complicated pathogeny involved in spontaneous abortion. At present, the focus of study is on the interface between mother and fetus, the trophoblasts. Indoleamine 2,3-dioxygenase (IDO) is the first and regulatory enzyme in the major route of l-tryptophan catabolism, which induces immunosuppression of T lymphocytes. In the present study we investigated the effect of Kidney-replenishing herb on the expression and activity of IDO in human syncytiotrophoblasts cultured in vitro and the balance of helper T cell (Th) cytokines.
  
  
  METHODS
  Syncytiotrophoblasts were cultured in vitro for 24, 48 or 72 h, with either control serum or serum made from Kidney-replenishing herb, without or with different concentrations of the IDO inhibitor 1-methyltryptophan (1-MT). Reverse transcription-polymerase chain reaction was applied to analyze the IDO mRNA transcription of syncytiotrophoblasts and Western blotting was applied to determine the expression of IDO protein in syncytiotrophoblasts. The concentration of interleukin-10 and interferon-gamma in co-culture medium of syncytiotrophoblasts and decidual T lymphocytes was determined by enzyme-linked immunosorbent assay. High-performance liquid chromatography was used to determine the concentration of kynurenine (Kyn) and tryptophan (Tyr) in the co-culture medium, and the ratio of Kyn/Try was used to assess IDO activity.
  
  
  RESULTS
  IDO mRNA and protein were detected in human syncytiotrophoblasts cultured in vitro. The IDO inhibitor 1-MT caused the balance of Th cytokines to depart from type 2; when IDO activity was inhibited, Kidney-replenishing herb improved the expression of IDO mRNA and protein, promoted IDO activity and caused the balance of Th cytokines depart from type 1.
  
  
  CONCLUSIONS
  Kidney-replenishing herb improves the expression of IDO mRNA and protein, promotes IDO activity to an appropriate value, resumes the balance of Th cytokines and regulates maternofetal tolerance.
authors.affiliation: The Hospital of Obstetrics & Gynecology, Fudan University, Shanghai, PR China. xuelianlixuelian@yahoo.com.cn
authors.forename: Xuelian
authors.initials: X
authors.lastname: Li
authors.forename: Suiqi
authors.initials: S
authors.lastname: Gui
authors.forename: Haiyan
authors.initials: H
authors.lastname: Wang
mesh_terms: D000818:Animals; D018920:Coculture Techniques; D029745:Codonopsis; D017077:Culture Media, Conditioned / Q000032:analysis; D016207:Cytokines / Q000032:analysis / Q000378:metabolism*; D046149:Embryo Culture Techniques; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006801:Humans; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D007371:Interferon-gamma / Q000032:analysis; D016753:Interleukin-10 / Q000032:analysis; D007737:Kynurenine / Q000032:analysis; D010946:Plants, Medicinal; D011247:Pregnancy; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D006377:T-Lymphocytes, Helper-Inducer / Q000378:metabolism*; D014327:Trophoblasts / Q000201:enzymology*; D014364:Tryptophan / Q000031:analogs & derivatives / Q000032:analysis / Q000494:pharmacology
chemical_list: D017077:Culture Media, Conditioned; D016207:Cytokines; D004791:Enzyme Inhibitors; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D012333:RNA, Messenger; D016753:Interleukin-10; D007737:Kynurenine; D007371:Interferon-gamma; D014364:Tryptophan; C525396:1-methyltryptophan