title: Regulatory T cell subtypes and TGF-β1 gene expression in chronic allograft dysfunction.
abstract: BACKGROUND
  Regulatory T cells have been suggested to have a protective role against acute rejection in allograft recipients. However, there is little information available about their contribution to chronic rejection process. The role of transforming growth factor-beta 1 (TGF-β1) as a profibrogenic and/or immunoregulatory cytokine in renal allografts is also controversial.
  
  
  OBJECTIVE
  To evaluate the frequency of CD4+CD25+CD127- and CD3+CD8+CD28- regulatory T cells in chronic allograft dysfunction (CAD) and to investigate the expression of TGF-β1 in renal allografts.
  
  
  METHODS
  Thirty biopsy-proven CAD patients were pair-matched with 30 stable graft function patients and a third group of healthy volunteers. Flowcytometry was performed on PBMCs to determine the frequency of CD3+CD8+CD28- and CD4+CD25+CD127- regulatory T cells in lymphocyt population. TGF-β1 gene expression was assessed by Real Time PCR.
  
  
  RESULTS
  The percentages of CD3+CD8+CD28- Tregs among renal allograft recipients was higher than healthy controls (p<0.001) since stable graft patients showed the most rates. The frequency of CD4+CD25+CD127- Tregs was lower in CAD patients than stable recipients (p=0.024) and healthy group (p=0.015). TGF-β1 gene expression was greater in CAD patients compared to healthy group (p=0.03) but there was no significant difference between gene expression of stable graft patients and healthy volunteers.
  
  
  CONCLUSIONS
  The negative association between the frequency of regulatory T cell subtypes and chronic allograft dysfunction proposes these cells as probable candidates for promoting allograft survival. Moreover, despite the immunoregulatory capacity of TGF-β1, it is likely to be implicated in chronic damages of allograft tissue.
authors.affiliation: Department of Immunology, School of medicine, Tehran University of medical sciences, Tehran, Iran, e-mail: saraasadiasl@gmail.com.
authors.forename: Sara
authors.initials: S
authors.lastname: Assadiasl
authors.forename: Pedram
authors.initials: P
authors.lastname: Ahmadpoor
authors.forename: Mohsen
authors.initials: M
authors.lastname: Nafar
authors.forename: Mahboob
authors.initials: M
authors.lastname: Lessan Pezeshki
authors.forename: Fateme
authors.initials: F
authors.lastname: Pourrezagholi
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Parvin
authors.forename: Abtin
authors.initials: A
authors.lastname: Shahlaee
authors.forename: Adel
authors.initials: A
authors.lastname: Sepanjnia
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Nicknam
authors.forename: Aliakbar
authors.initials: A
authors.lastname: Amirzargar
mesh_terms: D000328:Adult; D064591:Allografts / Q000378:metabolism* / Q000473:pathology; D000954:Antigens, Surface / Q000378:metabolism; D016022:Case-Control Studies; D003404:Creatinine / Q000097:blood / Q000652:urine; D005260:Female; D015870:Gene Expression; D006801:Humans; D016130:Immunophenotyping; D016030:Kidney Transplantation / Q000009:adverse effects; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000235:genetics* / Q000473:pathology; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000235:genetics*
chemical_list: D000954:Antigens, Surface; D053773:Transforming Growth Factor beta1; D003404:Creatinine