US nanoengineers have developed COVID-19 vaccine candidates that do not need cold-chain distribution.
The fridge-free vaccines are in the early stage of development, but triggered high production of neutralising antibodies against SARS-CoV-2 in mice.
If they prove to be safe and effective in people, the vaccines could play an important role in global distribution efforts, especially for rural areas or resource-poor communities.
Professor of Nanoengineering Nicole Steinmetz said: “It could easily reach places where setting up ultra-low temperature freezers, or having trucks drive around with these freezers, is not possible.”
The researchers created two vaccine candidates. One is made from a plant virus called cowpea mosaic virus. One is made from a bacterial virus called Q beta.
The researchers used cowpea plants and E. coli bacteria to grow millions of copies of the plant virus and bacterial virus.
They then attached a small piece of the SARS-CoV-2 spike protein to the surface. The finished products look like an infectious virus, so the immune system can recognise them and the small piece of the spike protein attached to the surface stimulates the body to generate an immune response against the coronavirus.
Image credit | iStock
