Researchers in the United States have developed an inhalable, self-administered COVID-19 vaccine that is shelf-stable at room temperature for up to a duration of three months. The researchers discovered that this delivery mechanism, an exosome produced from the lung and termed LSC-Exo, is more effective for avoiding the lung’s lining than the lipid-based nanoparticles currently used. These exosomes are extracellular vesicles that contain metabolites, proteins, lipids, and nucleic acids.
The study, published in the journal Nature Biomedical Engineering, outlines the process of creating a vaccine prototype that can be used successfully with protein-based vaccines from the evidence of concept to animal tests done.
Details about the vaccine
According to researchers, a vaccination that is stable at room temperature and could be administered by the patient themselves would significantly minimize waiting time for patients as well as the strain on the medical community during a pandemic. However, they said that in order for it to function by inhalation, the delivery system needs to be reformulated.
Ke Cheng from the University of North Carolina at Chapel Hill said, “An inhalable vaccine will confer both mucosal and systemic immunity, it is more convenient to store and distribute, and it could be self-administered on a large scale.” He further added, “So while there are still challenges associated with scaling up production, we believe that this is a promising vaccine worthy of further research and development.”
The researchers sought to overcome a number of difficulties related to vaccination delivery. The first one according to researchers is vaccine taken via intramuscular is less at getting it into the lung system. Second, mRNA vaccines in their present form need to be administered by trained medical staff and kept in the freezer.
Cheng said, “Vaccines can work through various means. For example, mRNA vaccines deliver a script to your cell that instructs it to produce antibodies to the spike protein (which helps the virus to gain entry into a cell).” He further added, “This VLP vaccine, on the other hand, introduces a portion of the spike protein to the body, triggering the immune system to produce antibodies to the spike protein.”
