Detection of antibodies against equine herpesvirus types 1 and 4 by using recombinant protein derived from an immunodominant region of glycoprotein B.
The N-terminal fragment comprising residues +1 to +50 (gB1-50) of equine herpesvirus type 1 (EHV-1) glycoprotein B was expressed as a glutathione S-transferase fusion protein in Escherichia coli. Recombinant gB1-50 (rgB1-50) was recognized in immunoblots by sera from rabbits immunized with EHV-1 and by convalescent-phase sera from horses with natural EHV-1 infections. An enzyme-linked immunosorbent assay (ELISA) for monitoring antibody levels against EHV-1 was developed by using rgB1-50, and its specificity was assessed with a panel of reference antisera against other equine viruses. A specific cross-reaction was detected with EHV-4, which was confirmed by inhibition ELISA. Convalescent-phase sera from horses with natural EHV-1 or EHV-4 infections possessed antibody titers against rgB1-50 ranging from 1:2,000 to 1:64,000, indicating the presence of an immunodominant antigenic site. The study demonstrated the potential application of rgB1-50 as a diagnostic antigen and highlights the glutathione S-transferase fusion system as a simple and effective method of producing purified milligram quantities of antigen.
Department of Infectious Diseases, Animal Health Trust, Newmarket, Suffolk, England.
R
R
Sinclair
M M
MM
Binns
E D
ED
Chirnside
J A
JA
Mumford
D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000235:genetics; D001483:Base Sequence; D004279:DNA, Viral / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006564:Herpesviridae / Q000235:genetics / Q000276:immunology*; D006566:Herpesviridae Infections / Q000175:diagnosis / Q000662:veterinary; D004861:Herpesvirus 1, Equid / Q000235:genetics / Q000276:immunology*; D006734:Horse Diseases / Q000175:diagnosis; D006736:Horses; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology
D000914:Antibodies, Viral; D000956:Antigens, Viral; D004279:DNA, Viral; D011993:Recombinant Fusion Proteins; D014759:Viral Envelope Proteins; C040495:glycoprotein B, Simplexvirus