title: Evaluation of CD4+CD25+/-CD39+T-cell populations in peripheral blood of patients following kidney transplantation and during acute allograft rejection.
abstract: OBJECTIVE
  Regulatory T cells (Treg) are important in mediating immune tolerance and outcomes of allotransplantation. CD4+CD25+CD39+co-expression identifies memory Treg; CD4+CD25-CD39+memory T effectors. We sought to determine CD4+CD25+/-CD39+expression from the peripheral blood of patients with end stage renal failure, following transplantation and during episodes of acute cellular rejection.
  
  
  METHODS
  CD4+T cells were isolated from peripheral blood leucocytes and analysed for CD25 and CD39 expression by flow cytometry. Treg suppressive function was measured by suppression of autologous effector T-cell proliferation by Treg in co-culture.
  
  
  RESULTS
  CD4+CD25+/-CD39+T-cell subsets were tracked longitudinally in the peripheral blood of 17 patients following renal transplantation. Patients with acute T-cell-mediated rejection diagnosed on biopsy had reduced CD4+CD25+CD39+mTreg (P < 0.05) and CD4+CD25-CD39+mTeff (P < 0.01) cells compared with non-rejecting patients. CD4+CD25+CD39+mTreg (P < 0.05) and CD4+CD25-CD39+mTeff (P = 0.057) were reduced in long-term transplant patients (>1 year) compared with non-immunosuppressed controls. Interestingly, remaining CD4+CD25+CD39+mTreg in the stable transplant patients displayed more potent suppressive capacity compared with non-immunosuppressed controls (83.2% ± 3.1% vs 45.7% ± 8.0%, nTeff:Treg ratio 8:1, P < 0.01).
  
  
  CONCLUSIONS
  CD4+CD25+CD39+mTreg and CD4+CD25-CD39+mTeff in peripheral blood can be tracked in renal transplant patients. Acute cellular rejection was accompanied by reduced mTreg and mTeff. Determining changes in these T-cell subsets may help to identify patients with, or at high risk of, renal allograft rejection.
authors: Immunology Research Centre, Parkville, Melbourne, Victoria, Australia.
authors: Jennifer L
authors: JL
authors: McRae
authors: Immunology Research Centre, Parkville, Melbourne, Victoria, Australia.
authors: Joanne Sj
authors: JS
authors: Chia
authors: Immunology Research Centre, Parkville, Melbourne, Victoria, Australia.
authors: Sandra A
authors: SA
authors: Pommey
authors: Immunology Research Centre, Parkville, Melbourne, Victoria, Australia.|Department of Nephrology, St. Vincent's Hospital, Parkville, Melbourne, Victoria, Australia.|Department of Medicine, University of Melbourne, Parkville, Melbourne, Victoria, Australia.
authors: Karen M
authors: KM
authors: Dwyer
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D064591:Allografts; D015703:Antigens, CD / Q000097:blood*; D001081:Apyrase / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D049109:Cell Proliferation; D002478:Cells, Cultured; D018920:Coculture Techniques; D005260:Female; D006084:Graft Rejection / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology*; D006085:Graft Survival; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D053645:Interleukin-2 Receptor alpha Subunit / Q000097:blood*; D007676:Kidney Failure, Chronic / Q000097:blood / Q000276:immunology / Q000601:surgery*; D016030:Kidney Transplantation / Q000009:adverse effects*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011446:Prospective Studies; D012307:Risk Factors; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology*; D013997:Time Factors; D023001:Transplantation Tolerance; D016896:Treatment Outcome
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; C508017:IL2RA protein, human; D007166:Immunosuppressive Agents; D053645:Interleukin-2 Receptor alpha Subunit; D001081:Apyrase; C067869:CD39 antigen
keywords: CD39; Treg; acute cellular rejection; kidney; renal transplantation