Construction and immunogenicity of chimeric peptide antigen composed of M2e and NP genes of avian influenza virus

Abstract:

Abstract: [Objective] In order to overcome the defect of traditional avian influenza vaccine that lacks cross-protection among different serotypes, we developed a universal anti-influenza vaccine. [Methods] Based on the gene analysis for AIV matrix protein 2 and two cytotoxic T-lymphocyte epitopes, we constructed four prokaryotic expression vectors. The target gene was induced by IPTG and the fusion protein was mixed with Freund’s adjuvant; then used to immunize20-day-old chicken by intramuscular injection and boosted 3 weeks later. Blood samples were collected weekly following the primary vaccination. The anti-M2e antibody was detected with ELISA coated by synthesized peptide; the neutralizing ability of anti-serum was evaluated on MDCK cell line and chick embryo; the CD4+ and CD8+ T lymphocyte amounts in peripheral blood of immunized chicken were measured by flow cytometry. [Results] The fusion protein induced immunological reaction, and the antibody bound with the viral M2 protein expressed on the surface of MDCK cells. Serum could only inhibit the replication without neutralizing the virus. Flow cytometry results showed that CD4+ and CD8+ T lymphocyte in peripheral blood increased obviously following immunization (P<0.05), which possessed the character of cell immunization. [Conclution] Chimeric peptides kept good immuno-genicity and provided useful probes for the control of avian influenza.