title: Quantitative and qualitative study of enzyme-linked immunosorbent assay to detect IgG against Japanese encephalitis virus in swine sera.
abstract: This study was designed to investigate the application of indirect enzyme-linked immunoassay (ELISA) in detecting IgG against Japanese encephalitis virus in swine sera and the qualitative nature of this test. The attenuated strain SA14-14-2 of Japanese encephalitis virus (JEV) was inoculated into 9-day-old chicken embryos and virus was harvested, purified and suspended in 0.9% saline as JEV antigen. The control antigen was prepared by the same method as for the antigen. In the ELISA, the optimal concentrations of antigen coated and dilution factor were selected using chi2 test. Ninety-two swine sera negative to haemagglutination inhibition (HI) were tested by this assay and the positive threshold was determined. The results of this study indicate that indirect ELISA has high specificity, sensitivity and reproducability. Simultaneous testing of 74 serum samples from nine pig farms was carried out to compare the existing HI test and the indirect ELISA. The coincidence rate of the two assays was 85.1% (63/74) and no significant difference was observed between them (p > 0.05). This ELISA test can detect 46 swine serum samples qualitatively and the titre of eight swine serum samples through endpoint dilution quantitatively within one 96-well plate.
authors.affiliation: College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Jia
authors.initials: J
authors.lastname: Xinglin
authors.forename: Chen
authors.initials: C
authors.lastname: Huanchun
authors.forename: Wang
authors.initials: W
authors.lastname: Xiang
authors.forename: Qi
authors.initials: Q
authors.lastname: Changming
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D002460:Cell Line; D004664:Encephalitis Virus, Japanese / Q000276:immunology; D004672:Encephalitis, Japanese / Q000175:diagnosis / Q000662:veterinary*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary*; D007074:Immunoglobulin G / Q000097:blood*; D012680:Sensitivity and Specificity; D013552:Swine; D013553:Swine Diseases / Q000175:diagnosis* / Q000821:virology; D014776:Virus Cultivation
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G
references.citation: Indian J Med Res. 1991 Sep;93:271-6
references.pmid: 1663915
references.citation: J Clin Microbiol. 1998 Jul;36(7):2030-4
references.pmid: 9650956
references.citation: Am J Vet Res. 1985 Oct;46(10):2054-7
references.pmid: 2998237
references.citation: J Virol Methods. 1983 Jul;7(1):21-8
references.pmid: 6311855
references.citation: Vet Res Commun. 2002 Aug;26(6):495-503
references.pmid: 12241102
references.citation: Am J Epidemiol. 1966 Sep;84(2):292-300
references.pmid: 4380585
references.citation: Southeast Asian J Trop Med Public Health. 1985 Jun;16(2):199-206
references.pmid: 2999995
references.citation: J Virol Methods. 1982 Dec;5(5-6):247-53
references.pmid: 6298264