title: Pretreatment of serum samples to reduce interference of colostrum-derived specific antibodies with detection of Bovine viral diarrhea virus antigen by ELISA in young calves.
abstract: Antigen enzyme-linked immunosorbent assay (ELISA) is used for the detection of Bovine viral diarrhea virus persistently infected (BVDV PI) cattle; however, colostrum-derived antibodies may interfere with antigen detection in serum from young PI calves. Our study aimed to assess serum pretreatment methods for reducing such interference. Dilution of PI serum with serum containing specific antibody showed that antibody levels equivalent to those observed in colostrum-fed calves were able to eliminate all antigen signals in a serum sample. Serum was treated with ethylenediamine tetra-acetic acid at pH 4.5, 5.5, 6.5, and 7.5, then boiled, centrifuged, and the supernatant-recovered. BVDV antibody was undetectable by ELISA in supernatants from treated samples, and the antigen ELISA signal was improved. Maximum antigen signal recovery of >90% was achieved at pH 5 ± 0.5. When this optimal treatment method was applied to field samples from 3 PI calves (which were negative in the antigen-capture ELISA without treatment), the antigen signal improved and gave a positive result in each case. Pretreatment may provide an improvement in the detection of young PI calves.
authors.affiliation: School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Roseworthy, South Australia, Australia sasha.lanyon@adelaide.edu.au.
authors.forename: Sasha R
authors.initials: SR
authors.lastname: Lanyon
authors.affiliation: School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Roseworthy, South Australia, Australia.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Reichel
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000914:Antibodies, Viral / Q000097:blood; D000956:Antigens, Viral / Q000097:blood; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000097:blood / Q000175:diagnosis* / Q000821:virology; D002417:Cattle; D003126:Colostrum / Q000276:immunology*; D001908:Diarrhea Viruses, Bovine Viral / Q000276:immunology / Q000302:isolation & purification*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary*; D005260:Female; D011247:Pregnancy
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral
keywords: Bovine viral diarrhea; colostrum-derived antibody; detection gap; pretreatment