title: Enzyme immunoassay for the measurement of human tenascin-C on the Bayer Immuno 1 analyzer.
abstract: OBJECTIVE
  To evaluate a new tenascin-C assay performed on the Bayer Immuno 1 system.
  
  
  METHODS
  The precision was measured using three levels of serum pools. Linearity was tested by diluting patient serum samples containing high tenascin-C concentrations, and the minimal detectable concentration determined by repetitive analysis of the zero calibrator. Preliminary reference intervals were determined by testing serum samples from 220 healthy individuals. Biovariability was estimated in a cohort of 20 apparently healthy subjects over 18 days. The levels of tenascin-C in patients with different liver diseases was tested.
  
  
  RESULTS
  The detection limit was 2 ng/mL. At concentrations ranging from 325 to 1957 ng/mL the assay demonstrated within-run and between-run CVs ranging from 4% to 3.6% and 8.4% to 6.7%, respectively. Dilutions of sera were linear and parallel to the standard curve with recoveries ranging from 97% to 100%. The reference interval (central 95% interval) for tenascin-C in serum of healthy adults was 199-906 ng/mL. The variability study yielded an analytical variability, CV(A), of 1.8%; a within-subject variability, CV(I), of 11.7%; and a between-subject variability, CV(G), of 39.3%. Tenascin-C concentrations in sera of liver disease patients were significantly increased.
  
  
  CONCLUSIONS
  The novel assay provides a rapid and reliable procedure for the determination of tenascin-C levels in human sera.
authors.affiliation: Bayer AG, Central Research, Leverkusen, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Ropers
authors.forename: W
authors.initials: W
authors.lastname: Kroll
authors.forename: M
authors.initials: M
authors.lastname: Becka
authors.forename: M
authors.initials: M
authors.lastname: Voelker
authors.forename: E R
authors.initials: ER
authors.lastname: Burchardt
authors.forename: D
authors.initials: D
authors.lastname: Schuppan
authors.forename: M
authors.initials: M
authors.lastname: Gehrmann
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D001682:Biological Availability; D001793:Blood Preservation; D002138:Calibration; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation* / Q000592:standards; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008107:Liver Diseases / Q000097:blood; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D019063:Tenascin / Q000097:blood* / Q000276:immunology / Q000493:pharmacokinetics
chemical_list: D000911:Antibodies, Monoclonal; D019063:Tenascin