Targeting Respiratory Viruses: The Efficacy of Intranasal mRNA
Vaccination in Generating Protective Mucosal and Systemic Immunity
Against Influenza A (H1N1)
Abstract
Four significant influenza outbreaks have occurred over the past 100
years, and the 1918 flu pandemic is the most severe. Since influenza
viruses undergo antigenic evolution, they are the pathogens most likely
to trigger a new pandemic shortly. Intranasal vaccination offers a
promising strategy for preventing diseases triggered by respiratory
viruses by eliciting an immunoglobulin A (IgA) response, limiting virus
replication and transmission from the respiratory tract more efficiently
than intramuscular vaccines. Combining intranasal administration and
mRNA-lipid nanoparticles can be an ideal strategy for limiting the
extent of the next flu pandemic. This study explored the immunogenicity
of intranasally delivered mRNA encapsulated in
mannose-histidine-conjugated chitosan lipid nanoparticles (MHCS-LNPs) as
a vaccine against influenza A (H1N1) in BALB/c mice. Intranasal
administration of mRNA-MHCS-LNPs resulted in the generation of influenza
A (H1N1) hemagglutinin-specific neutralizing antibodies in vaccinated
animals. The ELISA results indicated a notable increase in the quantity
of IgG and IgA antibodies in serum and the Bronchoalveolar Lavage Fluid
(BALF), respectively, and exhibited influenza A-specific IFN-γ secretion
in vaccinated mice, as well as a noticeable alteration in IL-5
production. Overall, this study demonstrated an effective immunogenic
response against respiratory viral infections through intranasal
delivery of an mRNA-MHCS-LNP vaccine.