Immunogenicity Studies on Nanoparticle Based Vaccines for Bird Flu

J. Li, S. Emadi, A. Tan, P. Burkhard, B.S. Ladman, J. Gelb, Jr., M.I. Khan
University of Connecticut, US

Keywords: nanoparticle, avian Influenza, vaccine, SAPN

Summary:

Bird flu or avian influenza (AI)outbreaks pose a significant risk to poultry production and human health as well. Vaccine designing, however, is challenging due to the highly mutable genome of influenza virus. Our recently developed protein nanoparticle technology has been demonstrated as powerful platform for the delivery of epitopes to elicit strong immune response, providing promise in the development of universal influenza vaccines. Particularly, in this study, four self-assembled protein nanoparticles (SAPNs) were designed to organize the AI M2e domain as a tetramer along with either the conserved helices A or C, the cleavage peptide of hemagglutinin or a chicken specific T cell epitope (HTL), respectively in each construct. Groups of specific pathogen free (SPF) chickens were immunized. ELISA results suggest that tetra-M2e-HTL and tetra-M2e-helix A construct induce strong antibody titers in serum of vaccinated chicken compared to control groups. Immunogenicity studies are in progress to analyze virus neutralization and T cell mediated immunity induced by these constructs using lymphocyte proliferation and flow cytometry. The most promising nanoparticle vaccine will then be evaluated in challenge of immunity studies using a highly pathogenic AIV. These studies will advance this innovative vaccine platform by developing an AI vaccine based on B and T cell epitopes from hemagglutinin and M2e.