Characterization of cross protection of Swine-Origin Influenza Virus (S-OIV) H1N1 and reassortant H5N1 influenza vaccine in BALB/c mice given a single-dose vaccination

Abstract

BackgroundInfluenza virus has antigen drift and antigen shift effect, vaccination with some influenza vaccine might not induce sufficient immunity for host to the threat of other influenza virus strains. S-OIV H1N1 and H5N1 influenza vaccines in single-dose immunization were evaluated in mice for cross protection to the challenge of A/California/7/2009 H1N1 or NIBRG-14 H5N1 virus.ResultsBoth H1N1 and H5N1 induced significant homologous IgG, HAI, and microneutralization antibody responses in the mice, while only vaccines plus adjuvant produced significant heterogeneous IgG and HAI antibody responses. Both alum and MPLA adjuvants significantly reduced the S-OIV H1N1 vaccine dose required to elicit protective HAI antibody titers from 0.05 μg to 0.001 μg. Vaccines alone did not protect mice from challenge with heterogeneous influenza virus, while H5N1 vaccine plus alum and MPLA adjuvants did. Mouse body weight loss was also less significant in the presence of adjuvant than in the vaccine without adjuvant. Furthermore, both H1N1 and H5N1 lung viral titers of immunized mice were significantly reduced post challenge with homologous viruses.ConclusionOnly in the presence of MPLA adjuvant could the H5N1 vaccine significantly reduce mouse lung viral titers post H1N1 virus challenge, and not vice versa. MPLA adjuvant induced cross protection with a single dose vaccination to the challenge of heterogeneous influenza virus in mice. Lung viral titer seemed to be a better indicator compared to IgG, neutralization antibody, and HAI titer to predict survival of mice infected with influenza virus.

Adjuvantation of an Influenza Hemagglutinin Antigen with TLR4 and NOD2 Agonists Encapsulated in Poly(D,L-Lactide-Co-Glycolide) Nanoparticles Enhances Immunogenicity and Protection against Lethal Influenza Virus Infection in Mice

“…Along with that, this group of mice was characterized by maximal HI titers (GMT-1:211). According to a previous publication using the same virus strain, HI titers of >1:40 were considered as markers of protection [38]. The effect of a complex immunoadjuvant on cellular immunity was clarified by a significant increase of splenic CD4 T-cells that were proliferating and/or activated (measured by IFN-γ production) in response to hemagglutinin restimulation in vitro.…”

Systemic prime mucosal boost significantly increases protective efficacy of bivalent RSV influenza viral vectored vaccine

“…Whilst other animal models such as ferret for influenza virus and cotton rat for RSV may recapitulate aspects of the human immune response, the mouse model is well established for these https://doi.org/10.1038/s41541-024-00912-1 types of immunogenicity and challenge study 41,42 ; it can be used to discern and predict which regimens/vaccines may be more immunogenic and protective over others. It also has considerable overlaps with human infection, especially severe disease following infection [41][42][43][44][45][46][47][48][49] . Assessment of the immunogenicity and protection conferred after vaccination with ChA-dOx1-NP + M1-RSVF supports further clinical development.…”

T cell mediated immunity against influenza H5N1 nucleoprotein, matrix and hemagglutinin derived epitopes in H5N1 survivors and non-H5N1 subjects

“…There were several studies on the immune responses to H5N1 virus infection based on the in vitro or ex vivo system of animal origins ( O’Neill et al, 2000 ; Seo & Webster, 2001 ; Seo, Peiris & Webster, 2002 ; Droebner et al, 2008 ; Sawai et al, 2008 ; Galli et al, 2009 ; Richards, Chaves & Sant, 2009 ; Van Maurik et al, 2010 ; Rimmelzwaan & Katz, 2013 ; Lin et al, 2013 ; Ross et al, 2014 ; Park et al, 2014 ; Koutsakos, Kedzierska & Subbarao, 2019 ). Conversely, there is limited information on the immune responses against H5N1 virus infection in humans, particularly in terms of cell-mediated immunity (CMI) which plays an essential role on viral clearance by eliminating the virus-infected cells ( Boon et al, 2004 ; Thomas et al, 2006 ; Mbawuike, Zhang & Couch, 2007 ; Rimmelzwaan & Katz, 2013 ; Koutsakos, Kedzierska & Subbarao, 2019 ).…”