title: Virus-coated layer-by-layer colloids as a multiplex suspension array for the detection and quantification of virus-specific antibodies.
abstract: BACKGROUND
  Suspension array technology has surpassed ELISA for automated, simultaneous detection and quantification of soluble biomarkers such as virus-specific antibodies. We describe assays in which antigens are attached to a lipid bilayer surrounding color-coded particles.
  
  
  METHODS
  We used layer-by-layer technology to establish a multiplex suspension array with distinguishable microbeads coated with authentic viral surfaces to catch and quantify virus-specific antibodies in a flow cytometric analysis. Antigenic surfaces were generated by chimeric and wild-type baculoviruses plus 2 different influenza A virus subtypes fused to a lipid bilayer surrounding distinctly colored particles. Specificity of binding of chosen antibodies and sera was detected by immunofluorescence. Results of multiplex analysis were compared with results of ELISA.
  
  
  RESULTS
  Titrations of virus-specific antibodies in the multiplex suspension array demonstrated specific binding to the viral surface proteins. The multiplex suspension array gave positive results for up to log 5-diluted primary antibodies with an approximately 5- to 10-fold reduced dynamic range compared with the respective ELISA.
  
  
  CONCLUSIONS
  The bead-based multiplex suspension array is customizable and easy to establish. By displaying native influenza A virus surfaces and recombinant HIV-1 epitopes, the new assay provides a tool for the detection of major viral infections in humans.
authors.affiliation: Institute of Medical Physics and Biophysics, Leipzig University, Leipzig, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Toellner
authors.forename: Martin
authors.initials: M
authors.lastname: Fischlechner
authors.forename: Boris
authors.initials: B
authors.lastname: Ferko
authors.forename: Reingard Maria
authors.initials: RM
authors.lastname: Grabherr
authors.forename: Edwin
authors.initials: E
authors.lastname: Donath
mesh_terms: D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000737:chemistry*; D016367:Baculoviridae / Q000737:chemistry* / Q000235:genetics; D003102:Colloids; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000032:analysis; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D009980:Influenza A virus / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D008863:Microspheres; D014760:Viral Fusion Proteins / Q000032:analysis
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D003102:Colloids; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D008051:Lipid Bilayers; D014760:Viral Fusion Proteins