title: Establishment of multiplexed, microsphere-based flow cytometric assay for multiple human tumor markers.
abstract: OBJECTIVE
  The multiplexed, microsphere-based flow cytometric assay (MFCA) for multiple human tumor markers was established for the early screening and detection of suspected cancer patients.
  
  
  METHODS
  Covalent coupling of capture antibodies directed against their respective tumor markers to fluorescent microspheres was performed by following the protocols recommended by a commercial corporation with some modifications. The coupling efficiency and cross-reactivity were identified by the Luminex 100 system and associated software. The standard curve was constructed by using serial dilution of recombinant tumor marker standards and was validated by comparison with ELISA for quantifying the tumor markers in serum samples.
  
  
  RESULTS
  The identifications revealed that the coupling procedures were successful without non-specific cross-reactivity and the standard curve was highly efficient. However, it was necessary to ensure the quality control of the coupling process since slight variations in the coupling procedures could profoundly affect the density of capture reagents coupled to the microspheres and consequently adversely affect the assay precision. In addition to its multi-analyte capability, the MFCA system had definite advantages, such as higher reproducibility, greater dynamic range of measurement, and considerably less preparation time and labor over the conventional "gold standard", which was the ELISA.
  
  
  CONCLUSIONS
  The successful establishment of the MFCA system for the simultaneous detection of multiple tumor markers will provide the foundation for the further study of clinical applications.
authors.affiliation: Department of Hepatobiliary Surgery, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Sun
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.forename: Xiao-hui
authors.initials: XH
authors.lastname: Huang
authors.forename: Mao-chuan
authors.initials: MC
authors.lastname: Zhen
authors.forename: Wen
authors.initials: W
authors.lastname: Li
authors.forename: Long-juan
authors.initials: LJ
authors.lastname: Zhang
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D008863:Microspheres; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor