Study on the Immune Efficiency for General Vaccine Against Avian Influenza Virus Using Human Mycobacterium Tuberculosis hsp70 as the Carrier for Peptide Epitopes / 中国生物工程杂志

ABSTRACT

M2e gene of three copies for H5N1 subtype AIV was synthesized and fused with human mycobacterium tuberculosis hsp70 gene.The fused gene was cloned into the prokaryotic expression vector to get pET-3M2e and pET-3M2e-hsp70.Recombinant protein r3M2e and r3M2e-hsp70 were successfully expressed induced with IPTG and purified with Ni2+-NTA collumn.Following that,the immunity of the recombinant protein was analysized with Western blot.20-day-old AIV non-immunized chickens were vaccined with r3M2e and r3M2e hsp70,at the same time,Trx and KLH-M2e inoculated chickens were served as vector and positive controls.Two weeks after the primary vaccination,every group was boosted with the same vaccine as in the primary vaccination.The humoral immunity of the vaccined chickens was evaluated with antibody detection against M2e,cytopathic suppression test,and indirect fluorescence assay.The cellular immunity was estimated according to lymphocyte subtype analysis with flow cytometry and M2e specific cytokine detection.Four weeks after the boost vaccine,all groups were challenged with 100EID50 AIV of H9N2 subtype,and the virus from swabs was detected with Real-time PCR.Results indicated that r3M2e hsp70 vaccined chicken developed the better humoral and cellular immune response,also,made a better performance compared with r3M2e vaccined group in virus challenge.