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Yueh, J.

Publications and source records attributed to Yueh, J..

2 recordsLinked to original sources

A clade 2.3.4.4b H5N1 virus vaccine that elicits cross-protective antibodies against conserved domains of H5 and N1 glycoproteins

The continuous evolution and widespread dissemination of highly pathogenic avian influenza (HPAI) H5N1 viruses, particularly clade 2.3.4.4b, pose critical challenges to global pandemic preparedness. In this study, we assessed a low-dose inactivated split virus vaccine derived from clade 2.3.4.4b H5N1, formulated with an Alum/CpG adjuvant, using a preclinical mouse model. This vaccine induced potent humoral and cellular immune responses, generating high titers of cross-reactive antibodies targeting both hemagglutinin (HA) and neuraminidase (NA) glycoproteins across homologous and heterologous H5 clades. The Alum/CpG adjuvant enabled significant antigen dose-sparing while promoting a balanced Th1/Th2 immune profile. Functional analyses demonstrated strong virus neutralization, neuraminidase inhibition, and potent antibody-dependent cellular cytotoxicity activity. Additionally, the vaccine elicited robust antigen-specific CD4+ and CD8+ T cell responses and effectively controlled viral replication in the lungs, accompanied by reduced lung inflammation. Importantly, vaccinated mice were fully protected against lethal challenges with both the homologous clade 2.3.4.4b and heterologous clade 1 H5N1 viruses, despite low hemagglutination inhibition titers. Electron microscopy polyclonal epitope mapping revealed serum antibodies targeting multiple epitopes on homologous HA and NA, with some cross-reacting to conserved epitopes on heterologous proteins, underscoring broad immune recognition. Collectively, these results highlight the potential of this vaccine candidate to provide broad, multifunctional, and durable immunity against both current and emerging H5N1 threats, supporting its further development for pandemic preparedness.

microbiology↗

Immunogenicity and protective efficacy of an intranasal neuraminidase-based influenza virus vaccine adjuvanted with bacterial cell membrane-derived adjuvants

Influenza virus neuraminidase (NA) has emerged as a promising vaccine candidate due to its relatively stable antigenic structure and the ability of NA-specific antibodies to provide cross-protection within influenza virus subtypes. Since the influenza virus causes respiratory infections in humans, developing mucosal vaccines to protect the entry site of the virus is of high importance. Recombinant NA requires adjuvants to induce a protective immune response after mucosal administration. In the current study, we analyze the immunogenicity and protective efficacy of a recombinant NA-based influenza virus vaccine administered intranasally in combination with adjuvants consisting of outer membrane proteins from Neisseria meningitidis complexed with exogenous lipopolysaccharides (LPS) from Shigella flexneri or endogenous LPS from N. meningitidis. We evaluated the local and systemic humoral and cellular immune responses to adjuvanted recombinant N1 NA, analyzing the dynamics of local follicular T-helper (Tfh) cells and germinal center B cells (GCB) in nasal-associated lymphoid tissue (NALT) and tissue-resident memory T cells in lungs, as well as the levels of IgA and IgG in the upper and lower respiratory tracts. Finally, we performed a heterologous challenge study to test the ability of the investigated vaccine formulations to induce cross-protection. The study demonstrates that bacterial cell membrane-derived adjuvants significantly improve the immunogenicity and protective efficacy of the recombinant N1 NA-based influenza vaccine leading to protection against clade 2.3.4.4b H5N1 challenge. This finding supports the potential of these adjuvanted vaccines in providing effective mucosal immunity against influenza virus.

microbiology↗