title: Development of an indirect ELISA based on a truncated S protein of the porcine epidemic diarrhea virus.
abstract: Porcine epidemic diarrhea (PED) is a highly contagious, enteric disease of swine caused by the porcine epidemic diarrhea virus (PEDV). To find a suitable ELISA method to assess the infection of PEDV and the effectiveness of vaccines, we developed and evaluated an indirect enzyme-linked immunosorbent assay (iELISA) based on a truncated recombinant spike (S) protein expressed in Escherichia coli. The parameters of the iELISA were optimized, and the cutoff value determined as 0.259 by analyzing optical density (OD) values of 80 PEDV negative sera confirmed by western blot. Repeatability tests revealed that the coefficients of variation of positive sera within and between runs were both less than 10%. Cross-reactivity assays demonstrated that iELISA was PEDV-specific. A virus neutralization test with sera of 7 different OD values showed a positive correlation between the OD values and virus neutralization. The results suggest this iELISA is specific, sensitive, and repeatable. Further studies should focus on the relationship between OD values of sera and its virus neutralization.
authors: a Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Yufeng
authors: Y
authors: Li
authors: a Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Fangyuan
authors: F
authors: Zheng
authors: a Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Baochao
authors: B
authors: Fan
authors: b Department of Epidemiology and Public Health, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan.
authors: Hassan Mushtaq
authors: HM
authors: Muhammad
authors: a Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Yao
authors: Y
authors: Zou
authors: a Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Ping
authors: P
authors: Jiang
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood*; D015153:Blotting, Western; D018352:Coronavirus Infections / Q000276:immunology* / Q000821:virology; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D009500:Neutralization Tests; D053485:Porcine epidemic diarrhea virus / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D015203:Reproducibility of Results; D064370:Spike Glycoprotein, Coronavirus / Q000276:immunology*; D013552:Swine; D013553:Swine Diseases / Q000276:immunology* / Q000821:virology
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D011994:Recombinant Proteins; D064370:Spike Glycoprotein, Coronavirus
keywords: ELISA indirect; PEDV; indirect ELISA; neutralisation virale; protéine S tronquée; truncated S protein; virus neutralization