Identification of the Major Epitope in the G_L Protein of Equine Arteritis Virus (EAV) Recognized by Antibody in EAV-infected Horses Using Synthetic Peptides

Abstract

A panel of overlapping peptides covering the ectodomain of the G_L protein of equine arteritis virus (EAV) was synthesized to identify the major epitope recognized by the EAV-seropositive horse sera by using enzyme-linked immunosorbent assay (ELISA). Three consecutive peptides, G15 (amino acid residues 75-90), G16 (79-94) and G17 (83-98), strongly reacted with 3 experimentally EAV-infected horse sera. G16 peptide was highly antigenic with all 8 EAV-infected horse sera tested. The ELISA absorbance values and the virus neutralization titers of antibodies in sera periodically collected from EAV-infected horses showed similar patterns. These results indicated that the major linear epitope of the EAV G_L protein which was recognized with EAV-infected horse sera was mapped to residues from 83 to 90.