title: Immunopotentiation of Different Adjuvants on Humoral and Cellular Immune Responses Induced by HA1-2 Subunit Vaccines of H7N9 Influenza in Mice.
abstract: In spring 2013, human infections with a novel avian influenza A (H7N9) virus were reported in China. The number of cases has increased with over 200 mortalities reported to date. However, there is currently no vaccine available for the H7 subtype of influenza A virus. Virus-specific cellular immune responses play a critical role in virus clearance during influenza infection. In this study, we undertook a side-by-side evaluation of two different adjuvants, Salmonella typhimurium flagellin (fliC) and polyethyleneimine (PEI), through intraperitoneal administration to assess their effects on the immunogenicity of the recombinant HA1-2 subunit vaccine of H7N9 influenza. The fusion protein HA1-2-fliC and HA1-2 combined with PEI could induce significantly higher HA1-2-specific IgG and hemagglutination inhibition titers than HA1-2 alone at 12 days post-boost, with superior HA1-2 specific IgG titers in the HA1-2-fliC group compared with the PEI adjuvanted group. The PEI adjuvanted vaccine induced higher IgG1/IgG2a ratio and significantly increased numbers of IFN-γ- and IL-4-producing cells than HA1-2 alone, suggesting a mixed Th1/Th2-type cellular immune response with a Th2 bias. Meanwhile, the HA1-2-fliC induced higher IgG2a and IgG1 levels, which is indicative of a mixed Th1/Th2-type profile. Consistent with this, significant levels, and equal numbers, of IFN-γ- and IL-4-producing cells were detected after HA1-2-fliC vaccination. Moreover, the marked increase in CD69 expression and the proliferative index with the HA1-2-fliC and PEI adjuvanted vaccines indicated that both adjuvanted vaccine candidates effectively induced antigen-specific cellular immune responses. Taken together, our findings indicate that the two adjuvanted vaccine candidates elicit effective and HA1-2-specific humoral and cellular immune responses, offering significant promise for the development of a successful recombinant HA1-2 subunit vaccine for H7N9 influenza.
authors.affiliation: Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, China.|Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu 225009, China.
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.affiliation: Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, China.|Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu 225009, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Xiong
authors.affiliation: Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, China.|Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu 225009, China.
authors.forename: Maozhi
authors.initials: M
authors.lastname: Hu
authors.affiliation: Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, China.|Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu 225009, China.
authors.forename: Xilong
authors.initials: X
authors.lastname: Kang
authors.affiliation: Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, China.|Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu 225009, China.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Pan
authors.affiliation: Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, China.|Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, Jiangsu 225009, China.
authors.forename: Xinan
authors.initials: X
authors.lastname: Jiao
mesh_terms: D000276:Adjuvants, Immunologic / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D058501:Enzyme-Linked Immunospot Assay; D005408:Flagellin / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry / Q000276:immunology; D054884:Host-Pathogen Interactions / Q000187:drug effects / Q000276:immunology; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects / Q000276:immunology*; D056724:Immunity, Humoral / Q000187:drug effects / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D064766:Influenza A Virus, H7N9 Subtype / Q000187:drug effects / Q000276:immunology* / Q000502:physiology; D007252:Influenza Vaccines / Q000276:immunology* / Q000494:pharmacology; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism; D015847:Interleukin-4 / Q000276:immunology / Q000378:metabolism; D008809:Mice, Inbred C3H; D009976:Orthomyxoviridae Infections / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D011094:Polyethyleneimine / Q000737:chemistry; D012486:Salmonella typhimurium / Q000378:metabolism; D018417:Th1 Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D022223:Vaccines, Subunit / Q000276:immunology / Q000494:pharmacology
chemical_list: D000276:Adjuvants, Immunologic; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007074:Immunoglobulin G; D007252:Influenza Vaccines; D022223:Vaccines, Subunit; D005408:Flagellin; D015847:Interleukin-4; D007371:Interferon-gamma; D011094:Polyethyleneimine