Linear Epitope Mapping of B-cell responses following immunization with Avian Reovirus S1133

William Dawe, Erich Linnemann, Vanessa Gauthiersloan, Holly Sellers - Poultry Diagnostic and Research Center, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA


Avian reovirus is a causative agents of tenosynovitis and viral arthritis. Commercially available reovirus vaccines do not protect against challenge with emerging variants associated with tenosynovitis and lameness.

Autogenous reovirus vaccines are commonly utilized to help protect against disease. Neutralizing epitopes of the host protective protein, Sigma C, have not been clearly defined.

In this study, linear epitope mapping of the Sigma C protein was performed on polyclonal chicken sera from SPF chickens vaccinated twice with S1133 commercial live attenuated/inactivated vaccines in the following treatments:

  • live and live
  • inactivated and inactivated
  • live and inactivated. Serum samples from individual birds were selected for epitope mapping based on virus neutralization and Western blot analysis. Epitope mapping was carried out using S1133 Sigma C sequence translated into linear 15 amino acid peptides with an overlap of 14 peptides.

Multiple proposed epitopes and single peptide interactions were identified. There was a common antibody response shared among the three vaccination groups around peptides with a consensus motif located on the intracapsid region of Sigma C.

The group two antibody response profile had higher detection intensities and more antigenic epitopes for peptides associated with the globular head of Sigma C than the other two groups. Identification of immunogenic epitopes for S1133 will serve as a baseline for the analysis of variants.

Source: 2018 AAAP Proceedings