title: Establishment of a decision tree model for diagnosis of early rheumatoid arthritis by proteomic fingerprinting.
abstract: OBJECTIVE
  The objective of this study was to identify proteomic biomarkers specific for rheumatoid arthritis (RA) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) in combination with weak cationic exchange (WCX) magnetic beads.
  
  
  METHODS
  Serum samples from 50 patients with RA and 110 disease controls (50 SLE and 60 SS) and 51 healthy individuals were analyzed. The samples were randomly divided into a training set or test set to develop a diagnostic model for RA.
  
  
  RESULTS
  A total of 83 protein peaks were identified to be related with RA, in which four of the peaks with mass-charge ratio (m/z) at 8133.85, 5844.60, 13 541.3 and 14 029.0 were selected to establish a model for diagnosis of RA. This classification model could separate patients with RA from diseased and healthy controls with sensitivity of 84.0% and specificity of 92.5%, and its accuracy was confirmed in the blind testing set with high sensitivity and specificity of 80.0% and 93.3%, respectively.
  
  
  CONCLUSIONS
  This study suggested that potential serum biomarkers for RA diagnosis could be discovered by MALDI-TOF-MS. The classification tree model set up in this study might be used as a novel diagnostic tool for RA.
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Xuewu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Yanying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Ru
authors.initials: R
authors.lastname: Li
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Rulin
authors.initials: R
authors.lastname: Jia
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, Beijing, China.
authors.forename: Zhanguo
authors.initials: Z
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D001798:Blood Proteins / Q000032:analysis*; D016022:Case-Control Studies; D002411:Cation Exchange Resins; D002852:Chromatography, Ion Exchange; D003661:Decision Support Techniques; D003663:Decision Trees; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010449:Peptide Mapping; D011237:Predictive Value of Tests; D040901:Proteomics / Q000379:methods*; D011897:Random Allocation; D015203:Reproducibility of Results; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D055815:Young Adult
chemical_list: D015415:Biomarkers; D001798:Blood Proteins; D002411:Cation Exchange Resins
keywords: mass spectrometry; matrix-assisted laser desorption/ionization time-of-flight; proteomics; rheumatoid arthritis