title: Immune monitoring in kidney transplant recipients could predict acute rejection by a new method: flow cytometric microcarrier assay.
abstract: BACKGROUND
  Peripheral blood lymphocytes (PBL) of kidney transplant recipients stimulated in vitro release tumor necrosis factor (TNF)-α and interferon (IFN)-γ into the supernate as detected by a flow cytometric microcarrier assay (FCMA) that we used to predict acute rejection episodes.
  
  
  METHODS
  Fifty-two kidney transplant recipients were divided into 2 groups; stable function (STA; n = 30) and acute rejection (ARG; n = 22) for comparison with healthy volunteers (n = 10). PBL were stimulated for 8 hours with phorbol myphnistate acetate and ionomycin, thereafter detecting TNF-α and IFN-γ in culture supernates by FCMA. Receiver operating characteristics (ROC) procedures were used to assess the sensitivity and specificity to predict acute rejection.
  
  
  RESULTS
  The fluorescence intensity of TNF-α and IFN-γ in culture supernates was significant higher among healthy controls than STA: 68.38 ± 28.59 vs 51.08 ± 34.05, respectively (P < .05). The intensity of TNF-α and IFN-γ in ARG (144.47 ± 81.21 and 116.61 ± 53.89, respectively) was significant higher than STA (P < .001). The sensitivity and specificity to predict acute rejection were 86.4% and 86.7%, respectively, when analyzed by ROC curves combining TNF-α and IFN-γ. The intensity in noncultured plasma from ARG or STA was significant lower than that in culture supernates from ARG and STA with sensitivity and specificity to predict acute rejection episodes of 63.6% and 73.3%, respectively, when combining TNF-α and IFN-γ.
  
  
  CONCLUSIONS
  Monitoring the expression of TNF-α and IFN-γ in cell culture supernates after stimulation of kidney transplant recipient PBL in vitro using FCMA predicted acute rejection episodes.
authors.affiliation: Department of Kidney Transplantation, Hospital of Nephropathy, First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Z-K
authors.initials: ZK
authors.lastname: Jin
authors.forename: C-X
authors.initials: CX
authors.lastname: Xu
authors.forename: P-X
authors.initials: PX
authors.lastname: Tian
authors.forename: W-J
authors.initials: WJ
authors.lastname: Xue
authors.forename: T-C
authors.initials: TC
authors.lastname: Mao
authors.forename: W-L
authors.initials: WL
authors.lastname: Duan
authors.forename: M
authors.initials: M
authors.lastname: Xi
mesh_terms: D016022:Case-Control Studies; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006084:Graft Rejection / Q000175:diagnosis / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000032:analysis; D016030:Kidney Transplantation; D008297:Male; D012372:ROC Curve; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma