Most vaccines are delivered into muscle, although HIV or SARS-CoV-2 infect through mucous membranes, which are targeted a new technique that elicited strong antibody responses against these viruses in tests with mice and non-human primates.
A study conducted by American researchers and published today by Science Translational Medicine presents a new intranasal vaccination platform with which immunizing proteins can be administered over the entire mucosal surface.
Although intranasal vaccines may elicit stronger and more protective antibody responses than injected vaccines, research has so far been limited by the low vaccination rate through the mucous membranes.
However, the new technology offers a “promising approach” administer vaccines through the nose and other mucosal surfaces instead of traditional injections, the scientific journal notes.
The research team, led by Brittany Hartwell of the Massachusetts Institute of Technology (MIT), has developed a strategy that allows immunostimulatory proteins travel through mucous surfacess.
They used amph proteins, which consist of viral proteins conjugated to a water-soluble end. whereby it binds to albumin. Albumin is a blood protein that crosses the mucosa by interacting with the neonatal cystic fibrosis receptor, which transports it bidirectionally across the mucosal epithelium, making it suitable as a mediator for vaccine delivery.
Amph can be formulated with the Env gp120 protein, which is found on the outer envelope of HIV, or with the SARS-Cov2 receptor binding domain (RBD) protein, which is the one that binds to human cells.
When administered intranasally to mice and macaques, it induces elevated concentrations of immunoglobulin G (IgG) and IgA antibodies in various mucosal tissues.
“These results could bode well for the possibility of a vaccine. to prevent HIV infection and have the potential to contribute to the goal of a vaccine against SARS-CoV-2, regardless of variant,” said Francis Szoka of the University of California in an accompanying article exploring the clinical implications of the study.