Novel inhalable COVID-19 vaccine Vaccine Coronavirus Disease COVID Inhalable natBME NCState UNC DukeMedSchool
Study: Exosomes decorated with a recombinant SARS-CoV-2 receptor-binding domain as an inhalable COVID-19 vaccine. Image Credit: WESTOCK PRODUCTIONS / Shutterstock
Early pathogen penetration is influenced significantly by the immune response of the airway mucosa, which results in humoral and cell-mediated immune responses that result in systemic reactions. As respiratory droplets are the primary means of SARS-CoV-2 transmission and the respiratory mucosa is the initial site of viral entry, inadequate mucosal immunity may restrict the effectiveness of intramuscularly delivered COVID-19 vaccinations.
The researchers validated optimal Exo delivery across the rodent lung's parenchyma and bronchi. They evaluated the retention and biodistribution of NPs in the murine lung. Furthermore, microscopic visualization and ex vivo imaging were conducted using red fluorescent protein loaded commercially available liposomes and LSC-Exo .
The authors discovered Exo biodistribution over liposomes in the lungs of healthy CD1 mice. They selected Exos as the foundation of the VLPs they created because of their exceptional lung retention and improved specificity of antigen-presenting cells . The average diameter of Exos was marginally enhanced by RBD decorating, according to nanoparticle tracking analysis . The study results validated the generation of RBD-Exo VLPs.
While RBD-Exo nebulization generated a type 1 T helper -biased immune reaction, RBD-Exo IV injection triggered a Th2-skewing immune response with selective IgG1 antibody production. Compared to RBD-Exo IV therapy, RBD-Exo VLP significantly increased the generation of RBD-selective IgA antibodies in serum complementary to the IgG isotype.