Mucosal DNA vaccine found effective in stopping Covid in its tracks: Study

A mucosal DNA vaccine was proved effective in stopping COVID-19 in its tracks, a small-scale study conducted in mice has found.

An international research team has demonstrated that its mucosal DNA vaccine is capable of ensuring the total survival of a group of mice infected with a version of the virus adapted to this species, whereas the latter kills 100 per cent of unvaccinated mice. Each group of mice tested consisted of 10 individuals, the study said.

The study is published in the Biomaterials journal.

Created using a vector developed by a Centre National de la Recherche Scientifique (CNRS) researcher at the Immunology and New Concepts in Immunotherapy Laboratory, Nantes University, France, this vaccine acts in a manner similar to that of RNA vaccines on the market.

The DNA delivered by the vector enters the target cells, causing them to produce a SARS-CoV-2 protein and allowing the immune system to prepare itself by producing antibodies and lymphocytes against the virus.

A vector is an element derived from medicinal chemistry used to deliver a molecule in a targeted manner. Here, the vector is a synthetic nanoparticle, the properties of which allow it to penetrate the mucous membranes and introduce DNA encoding a viral protein into the cells of the respiratory system.

Less known to the general public, mucosal vaccination via the mucus membranes could provide robust protection against SARS-CoV-2 infections, the study said.

Immune cells in the nose and lungs are considered better prepared to encounter and block the virus that causes COVID-19.

The vaccine's effectiveness against transmission between mice was not measured in this study, the study said.

However, the scientists hope that a vaccination method based on this principle could complement the current strategy, perhaps by providing better protection against transmission, the study said.