title: Serial ImmuKnow assay in stable kidney transplant recipients.
abstract: OBJECTIVE
  The ImmuKnow assay (cylex Inc., Columbia, MD) has been reported to measure the global immune monitoring tool for organ transplantation recipients. We assess immuKnow ATP values in stable kidney transplant patients.
  
  
  METHODS
  Patients who were kidney transplanted between September 2008 and May 2011 were enrolled in the prospective serial ImmuKnow assay study. The criteria of inclusion were living donor kidney transplantation (KT), no evidence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, and PRA less than 50%. ImmuKnow assay monitoring was performed at one day before operation, post operative weeks 4, 8, 12, 16, 20, 24, 36 and 52. We excluded patients who had undergone infectious syndrome or rejection episodes during the follow-up period.
  
  
  RESULTS
  Among 71 patients who were enrolled in prospective serial ImmuKnow assay monitoring, 37 patients were proven to stable KT patients during the follow-up period. Two hundred and twenty-four samples from 37 patients were collected. ImmuKnow value and immunosuppression drug level were compared in post operative weeks 4, 8, 12, 16, 20, 24, 36 and 52. The value of ImmuKnow assay was significantly different depending on the length of time after transplant (p = 0.038). Interestingly, the pre-transplant ImmuKnow values were lower than those of the immediate post-transplant period.
  
  
  CONCLUSIONS
  The ImmuKnow value of stable KT recipients is different according to "time after transplant". Therefore, "time after transplant" should be considered when applying an ImmuKnow assay in clinical practice.
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hyung Hwan
authors.initials: HH
authors.lastname: Moon
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Tae-Seok
authors.initials: TS
authors.lastname: Kim
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sanghoon
authors.initials: S
authors.lastname: Lee
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sanghyun
authors.initials: S
authors.lastname: Song
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Milljae
authors.initials: M
authors.lastname: Shin
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jae Berm
authors.initials: JB
authors.lastname: Park
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jong Man
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Division of Nephrology, Department of Medicine, Samsung Medical Centre, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hye Ryoun
authors.initials: HR
authors.lastname: Jang
authors.affiliation: Division of Nephrology, Department of Medicine, Samsung Medical Centre, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Wooseong
authors.initials: W
authors.lastname: Huh
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jae-Won
authors.initials: JW
authors.lastname: Joh
authors.affiliation: Departments of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sung Joo
authors.initials: SJ
authors.lastname: Kim
keywords: immune monitoring; immunosuppression; kidney transplantation