title: Altered expression of CD4(+)CD25(+) regulatory T cells and its 5-HT(1a) receptor in patients with major depression disorder.
abstract: BACKGROUND
  There is growing interest in immune imbalance observed in major depression, but the mechanism of this imbalance is still not well understood. CD4(+)CD25(+) regulatory T (Treg) cells are known to play an important role in immune regulation. However, their role in major depression has rarely been explored. The aims of this study are to determine the immune imbalance status in patients when first diagnosed with major depression, and to explore possible indications of Treg cell involvement in immune imbalance of major depression.
  
  
  METHODS
  27 patients with major depression and 27 healthy individuals were recruited in the study. The immune imbalance was observed by the analysis of Th cell cytokines and CD4(+)CD25(+) Treg cell level. The 5-HT in peripheral serum was measured with HPLC, and changes of Foxp3 and 5-HT(1a) receptor were observed by RT-PCR and double-immunofluorescence.
  
  
  RESULTS
  Despite the similar total lymphocyte count between patients and healthy individuals, the Th1/Th2 ratio increased and the CD4(+)CD25(+) Treg cells decreased in patients' peripheral blood. Moreover, we found that the level of 5-HT was decreased in peripheral serum, and the expression of 5-HT(1a) receptor was also decreased in peripheral lymphocytes of major depression patients, notably in the CD4(+)CD25(+) Treg cells rather than CD4(+)CD25(-) T cells.
  
  
  CONCLUSIONS
  The details of interaction between 5-HT(1a) receptors and Treg cells in major depression need further exploration.
  
  
  CONCLUSIONS
  CD4(+)CD25(+) Treg cells may contribute to the immune imbalance in patients with major depression, which could involve its interaction with 5-HT system.
authors.affiliation: Department of Neurology, Xiangya Hospital, Central South University, 87 Xiang Ya Road, Changsha, Hunan, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Xiao
authors.forename: Wenjing
authors.initials: W
authors.lastname: Qiu
authors.forename: Le
authors.initials: L
authors.lastname: Yang
authors.forename: Bo
authors.initials: B
authors.lastname: Hu
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Tian
authors.forename: Huan
authors.initials: H
authors.lastname: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D015704:CD4 Antigens / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D003865:Major Depressive Disorder / Q000235:genetics* / Q000276:immunology*; D005260:Female; D051858:Forkhead Transcription Factors / Q000235:genetics*; D006801:Humans; D016753:Interleukin-10 / Q000097:blood; D007376:Interleukin-2 / Q000097:blood; D053645:Interleukin-2 Receptor alpha Subunit / Q000097:blood*; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics; D044282:Receptor, Serotonin, 5-HT1A / Q000235:genetics*; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012701:Serotonin / Q000097:blood; D012737:Sex Factors; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D053773:Transforming Growth Factor beta1 / Q000097:blood; D055815:Young Adult
chemical_list: D015704:CD4 Antigens; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508017:IL2RA protein, human; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D012333:RNA, Messenger; D053773:Transforming Growth Factor beta1; D044282:Receptor, Serotonin, 5-HT1A; D016753:Interleukin-10; D012701:Serotonin