In a recent study published in Science Immunology, University of Minnesota researchers in collaboration with colleagues at Tiba Biotech and Emory University, demonstrated that nasal delivery of an RNA vaccine payload using Tiba’s biodegradable nanoparticle technology was able to induce adaptive immune responses in the respiratory tracts of mice.
New insights into needle-free delivery of RNA vaccines.
Despite the rapid embrace of mRNA vaccine technologies in response to the COVID-19 pandemic, the specific nature of tissue-specific immune responses has not been thoroughly investigated. In this study, researchers used self-amplifying RNA, a potent form of mRNA molecules, to express the influenza nucleoprotein antigen. Administration by this route led to robust T cell responses particularly in airway tissues, which may lead to greater protection against the respiratory virus at the site where it first invades the body. While typical intramuscular immunizations were able to drive lung-resident cellular immunity, an additional intranasal boost was shown to expand both circulating and lung resident memory T cells. These findings show that routes of administration and sequence of mRNA vaccination can induce antibody and lung cellular responses to pathogenic respiratory viruses.
The study was led by Dr. David Masopust of the University of Minnesota’s Department of Microbiology and Immunology and Center for Immunology, who said: “Tiba’s nanoparticle technology allows us to study the administration of RNA via a mucosal route without causing an interfering inflammatory response that would otherwise limit experimentation in vivo.”
In addition to the potential for improved efficacy against respiratory infections, needle-free vaccine delivery may help address supply chain issues in restricted resource environments and reduce vaccine hesitancy. The team plans to extend this work to further characterize the cellular immune responses to Tiba’s vaccines, and to further leverage this discovery in other respiratory viruses such as SARS-CoV-2 and the respiratory syncytial virus (RSV).
The study stems from earlier work on a universal influenza vaccine, funded in part by the NIH’s Collaborative Influenza Vaccine Innovation Centers (CIVIC) consortium. Additional funding was provided by the Swiss National Science Foundation and the Minnesota Partnership for Biotechnology and Medical Genomics.
For on-line access to the publication see: Route of self-amplifying mRNA vaccination modulates the establishment of pulmonary resident memory CD8 and CD4 T cells. Künzli et al., Sci Immunol. Vol. 7 No. 78 (Dec 2022). https://www.science.org/doi/10.1126/sciimmunol.add3075
