title: Establishment of a sandwich ELISA using commercial antibody for plasma or serum 3-nitrotyrosine (3NT). Elevation in inflammatory diseases and complementary between 3NT and myeloperoxidase.
abstract: BACKGROUND
  Amino acid tyrosine residue of a protein can be nitrated to form 3-nitrotyrosine (3NT), which is now being considered as a marker of inflammation, oxidative and nitrosative stress.
  
  
  METHODS
  An in-house ELISA has been established using the same commercial antibody for both binding and detection of 3NT containing proteins.
  
  
  RESULTS
  The sensitivity of the in-house ELISA was 1.8 nmol/l. The imprecision was <10% at all concentrations. The in-house assay correlates well with a commercial kit (r=0.89). In addition to EDTA plasma, we found that both heparinized plasma and serum can also be used to quantify 3NT concentration. Using the in-house ELISA we have detected increased concentrations of 3NT in diseases known to be associated with inflammation and also in subjects with polyps. As marker of oxidative stress and inflammation, both 3NT and myeloperoxidase are complementary to each other in test sensitivity.
  
  
  CONCLUSIONS
  This ELISA can be used in the clinical laboratories to monitor the inflammatory disease activity and assess early risks that are associated with inflammation, oxidative and nitrosative stress.
authors.affiliation: ARUP Laboratories, Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah 84108, United States, and Department of Pathology, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Sun
authors.forename: Pi-Yueh
authors.initials: PY
authors.lastname: Chang
authors.forename: Kuo-Chien
authors.initials: KC
authors.lastname: Tsao
authors.forename: Tsu-Lan
authors.initials: TL
authors.lastname: Wu
authors.forename: Chien-Feng
authors.initials: CF
authors.lastname: Sun
authors.forename: Lily L
authors.initials: LL
authors.lastname: Wu
authors.forename: James T
authors.initials: JT
authors.lastname: Wu
mesh_terms: D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007249:Inflammation / Q000097:blood*; D051379:Mice; D009195:Peroxidase / Q000097:blood*; D011933:Reagent Kits, Diagnostic; D012016:Reference Values; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D011933:Reagent Kits, Diagnostic; C002744:3-nitrotyrosine; D014443:Tyrosine; D009195:Peroxidase