title: A pilot study of GC/MS-based serum metabolic profiling of acute rejection in renal transplantation.
abstract: OBJECTIVE
  Acute allograft rejection is one of the important complications after renal transplantation, and it is a deleterious factor for long-term graft survival. Rejection is a complex pathophysiologic process, which has been explained by transcriptome and proteome in RNA transcripts and proteins level respectively. How are serum metabolite levels in response to acute rejection? Can metabolite levels in serum be used to diagnose and explain acute renal allograft rejection?
  
  
  METHODS
  Gas chromatograph-mass spectrometry (GC-MS) was used to analyze serum metabolome in 22 recipients of acute rejection and 15 stable renal transplant recipients.
  
  
  RESULTS
  46 endogenous metabolites included amino acid, fatty acid, carbohydrate and other intermediate metabolites were identified in 37 recipients. Principal component analysis based on these metabolites discriminated acute rejection group from stable recipients. Among these metabolites, the levels of 17 metabolites were significant higher in rejection group than those in stable group. These included amino acid (phenylalanine, serine, glycine, threonine, valine), carbohydrate (galactose oxime, glycose, fructose), carboxylic acid, lipids and other metabolite such as lactate, urea and myo-inositol. The levels of 5 metabolites of alanine, lysine, leucine, aminomalonic acid and tetradecanoic acid were low in rejection group compared to stable group. The prediction accuracy of acute rejection was 77.3% and stable function was 100% by supervised clustering based on these 22 metabolites.
  
  
  CONCLUSIONS
  This study demonstrated that metabolic profile was changed in response to rejection process and renal function can be reflected by serum metabolite levels. This study showed potential capability to diagnose acute rejection by metabolome analysis.
authors.affiliation: Kidney Disease Center, the First Affiliated Hospital, College of Medicine, Zhejiang University, PR China.
authors.forename: You-Ying
authors.initials: YY
authors.lastname: Mao
authors.forename: Jing-Qing
authors.initials: JQ
authors.lastname: Bai
authors.forename: Jiang-Hua
authors.initials: JH
authors.lastname: Chen
authors.forename: Zhang-Fei
authors.initials: ZF
authors.lastname: Shou
authors.forename: Qiang
authors.initials: Q
authors.lastname: He
authors.forename: Jian-Yong
authors.initials: JY
authors.lastname: Wu
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.forename: Yi-Yu
authors.initials: YY
authors.lastname: Cheng
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000097:blood*; D002241:Carbohydrates / Q000097:blood*; D002264:Carboxylic Acids / Q000097:blood*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006084:Graft Rejection / Q000097:blood* / Q000276:immunology; D006801:Humans; D016030:Kidney Transplantation / Q000276:immunology*; D008297:Male; D008660:Metabolism; D008875:Middle Aged; D010865:Pilot Projects; D025341:Principal Component Analysis
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D002264:Carboxylic Acids