RESUMEN
Swine influenza viruses (SwIVs) cause considerable morbidity and mortality in domestic pigs, resulting in a significant economic burden. Moreover, pigs have been considered to be a possible mixing vessel in which novel strains loom. Here, we developed and evaluated a novel M2e-multiple antigenic peptide (M2e-MAP) as a supplemental antigen for inactivated H3N2 vaccine to provide cross-protection against two main subtypes of SwIVs, H1N1 and H3N2. The novel tetra-branched MAP was constructed by fusing four copies of M2e to one copy of foreign T helper cell epitopes. A high-yield reassortant H3N2 virus was generated by plasmid based reverse genetics. The efficacy of the novel H3N2 inactivated vaccines with or without M2e-MAP supplementation was evaluated in a mouse model. M2e-MAP conjugated vaccine induced strong antibody responses in mice. Complete protection against the heterologous swine H1N1 virus was observed in mice vaccinated with M2e-MAP combined vaccine. Moreover, this novel peptide confers protection against lethal challenge of A/Puerto Rico/8/34 (H1N1). Taken together, our results suggest the combined immunization of reassortant inactivated H3N2 vaccine and the novel M2e-MAP provided cross-protection against swine and human viruses and may serve as a promising approach for influenza vaccine development.
Asunto(s)
Animales , Femenino , Ratones , Anticuerpos Antivirales/sangre , Antígenos Virales/genética , Peso Corporal , Protección Cruzada/inmunología , Modelos Animales de Enfermedad , Epítopos de Linfocito T/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Vacunas contra la Influenza/inmunología , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/inmunología , Péptidos/genética , Distribución Aleatoria , Análisis de Supervivencia , Vacunas Sintéticas/inmunología , Replicación ViralRESUMEN
Current influenza virus vaccines are based on strain-specific surface glycoprotein hemagglutinin (HA) antigens and effective only when the predicted vaccine strains and circulating viruses are well-matched. The current strategy of influenza vaccination does not prevent the pandemic outbreaks and protection efficacy is reduced or ineffective if mutant strains emerge. It is of high priority to develop effective vaccines and vaccination strategies conferring a broad range of cross protection. The extracellular domain of M2 (M2e) is highly conserved among human influenza A viruses and has been utilized to develop new vaccines inducing cross protection against different subtypes of influenza A virus. However, immune mechanisms of cross protection by M2e-based vaccines still remain to be fully elucidated. Here, we review immune correlates and mechanisms conferring cross protection by M2e-based vaccines. Molecular and cellular immune components that are known to be involved in M2 immune-mediated protection include antibodies, B cells, T cells, alveolar macrophages, Fc receptors, complements, and natural killer cells. Better understanding of protective mechanisms by immune responses induced by M2e vaccination will help facilitate development of broadly cross protective vaccines against influenza A virus.
Asunto(s)
Anticuerpos , Linfocitos B , Proteínas del Sistema Complemento , Protección Cruzada , Brotes de Enfermedades , Hemaglutininas , Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Células Asesinas Naturales , Macrófagos Alveolares , Glicoproteínas de Membrana , Orthomyxoviridae , Pandemias , Receptores Fc , Linfocitos T , Vacunación , VacunasRESUMEN
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.