title: Development of a multiplex Luminex assay for detecting swine antibodies to structural and nonstructural proteins of foot-and-mouth disease virus in Taiwan.
abstract: OBJECTIVE
  Foot-and-mouth disease (FMD) and swine vesicular disease (SVD) are serious vesicular diseases that have devastated swine populations throughout the world. The aim of this study was to develop a multianalyte profiling (xMAP) Luminex assay for the differential detection of antibodies to the FMD virus of structural proteins (SP) and nonstructural proteins (NSP).
  
  
  METHODS
  After the xMAP was optimized, it detected antibodies to SP-VP1 and NSP-3ABC of the FMD virus in a single serum sample. These tests were also compared with 3ABC polypeptide blocking enzyme-linked immunosorbent assay (ELISA) and virus neutralization test (VNT) methods for the differential diagnosis and assessment of immune status, respectively.
  
  
  RESULTS
  To detect SP antibodies in 661 sera from infected naïve pigs and vaccinated pigs, the diagnostic sensitivity (DSn) and diagnostic specificity (DSp) of the xMAP were 90.0-98.7% and 93.0-96.5%, respectively. To detect NSP antibodies, the DSn was 90% and the DSp ranged from 93.3% to 99.1%. The xMAP can detect the immune response to SP and NSP as early as 4 days postinfection and 8 days postinfection, respectively. Furthermore, the SP and NSP antibodies in all 15 vaccinated but unprotected pigs were detected by xMAP. A comparison of SP and NSP antibodies detected in the sera of the infected samples indicated that the results from the xMAP had a high positive correlation with results from the VNT and a 3ABC polypeptide blocking ELISA assay. However, simultaneous quantitation detected that xMAP had no relationship with the VNT. Furthermore, the specificity was 93.3-94.9% with 3ABC polypeptide blocking ELISA for the FMDV-NSP antibody.
  
  
  CONCLUSIONS
  The results indicated that xMAP has the potential to detect antibodies to FMDV-SP-VP1 and NSP-3ABC and to distinguish FMDV-infected pigs from pigs infected with the swine vesicular disease virus.
authors: Animal Health Research Institute, New Taipei City, Taiwan; Graduate Institute of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan.
authors: Tsu-Han
authors: TH
authors: Chen
authors: Animal Health Research Institute, New Taipei City, Taiwan.
authors: Fan
authors: F
authors: Lee
authors: Animal Health Research Institute, New Taipei City, Taiwan.
authors: Yeou-Liang
authors: YL
authors: Lin
authors: Animal Health Research Institute, New Taipei City, Taiwan.
authors: Chu-Hsiang
authors: CH
authors: Pan
authors: Animal Health Research Institute, New Taipei City, Taiwan.
authors: Chia-Ni
authors: CN
authors: Shih
authors: Animal Health Research Institute, New Taipei City, Taiwan.
authors: Chun-Hsien
authors: CH
authors: Tseng
authors: Animal Health Research Institute, New Taipei City, Taiwan; Graduate Institute of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan. Electronic address: tsaihj@ntu.edu.tw.
authors: Hsiang-Jung
authors: HJ
authors: Tsai
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000276:immunology; D036022:Capsid Proteins / Q000276:immunology*; D003937:Diagnosis, Differential; D029822:Enterovirus B, Human / Q000276:immunology; D005536:Foot-and-Mouth Disease / Q000175:diagnosis* / Q000276:immunology; D029544:Foot-and-Mouth Disease Virus / Q000276:immunology*; D007118:Immunoassay / Q000379:methods*; D012680:Sensitivity and Specificity; D013552:Swine; D013553:Swine Diseases / Q000175:diagnosis* / Q000276:immunology; D013624:Taiwan; D017361:Viral Nonstructural Proteins / Q000276:immunology*
chemical_list: C109754:3ABC protein, virus; D000914:Antibodies, Viral; D000956:Antigens, Viral; D036022:Capsid Proteins; C442501:VP1 protein, Foot-and-mouth disease virus; D017361:Viral Nonstructural Proteins
keywords: antibody detection; foot-and-mouth disease virus; multiplex Luminex assay; nonstructural protein; structural protein