title: Immune function assay (ImmuKnow) as a predictor of allograft rejection and infection in kidney transplantation.
abstract: BACKGROUND
  The Cylex ImmuKnow (IK) assay provides a rapid and quantitative assessment of T-cell-mediated immune function. Studies have shown correlations between ImmuKnow assay and adverse events, such as immunosuppression and low or high calcineurin inhibitor trough levels. We investigated the correlation between IK changes and rejection or infection in kidney transplant patients and studied the potential application of the IK assays in optimizing individual immunosuppressive therapy.
  
  
  METHODS
  ImmuKnow assay was used to determine dynamic intracellular ATP changes in CD4 cells in 193 samples from 42 kidney transplant patients and 25 healthy subjects. Patients were categorized into rejection, infection, and event-free groups. The IK values were assayed and analyzed between kidney transplant patients and healthy controls.
  
  
  RESULTS
  Most IK values fell between 200 and 599 ng/mL from pre-transplantation to 30 months post-transplantation. The mean IK values continuously increased throughout 30 months. Incidental allograft rejection patients had significantly higher IK values compared with the event-free patients and controls. However, infection patients had significantly lower IK values. Seven days after treatment, IK values in rejection/infection patients were different compared with the values in autograft patients, and there was a significant correlation between calcineurin inhibitor (FK506) trough levels and IK values in rejection/infection patients. Serum creatinine levels in the rejection patients were significantly higher than those in the event-free patients, and C-reactive protein levels were significantly higher in the infection patients compared with the event-free patients.
  
  
  CONCLUSIONS
  The IK assay combined with other biomarkers can be used to identify kidney transplant patients at high risk of rejection and infection.
authors.affiliation: Department of HLA Laboratory, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China. junhe1964@163.com
authors.forename: Jun
authors.initials: J
authors.lastname: He
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Xudong
authors.initials: X
authors.lastname: Wei
authors.forename: Hao
authors.initials: H
authors.lastname: Zheng
authors.forename: Chao
authors.initials: C
authors.lastname: Xu
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Bao
authors.forename: Xiaoni
authors.initials: X
authors.lastname: Yuan
authors.forename: Jianquan
authors.initials: J
authors.lastname: Hou
mesh_terms: D000293:Adolescent; D000328:Adult; D064591:Allografts; D015415:Biomarkers / Q000097:blood*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006084:Graft Rejection / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D007111:Immunity, Cellular / Q000276:immunology; D007159:Immunologic Tests; D007165:Immunosuppression Therapy; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000276:immunology; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000601:surgery; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009894:Opportunistic Infections / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D007166:Immunosuppressive Agents
keywords: ImmuKnow; immune monitoring; infection; kidney transplantation; rejection