Washington: MIT engineers have developed a new type of nanoparticle that protects the vaccine long enough to generate a strong immune response - not only in the lungs, but also in mucosal surfaces far from the vaccination site, such as the gastrointestinal and reproductive tracts.
Such vaccines could help protect against influenza and other respiratory viruses, or prevent sexually transmitted diseases such as HIV, herpes simplex virus and human papilloma virus, Darrell Irvine, an MIT professor of materials science and engineering and biological engineering and the leader of the research team, said.
He is also exploring use of the particles to deliver cancer vaccines.
"This is a good example of a project where the same technology can be applied in cancer and in infectious disease. It's a platform technology to deliver a vaccine of interest," Irvine, who is a member of MIT's Koch Institute for Integrative Cancer Research and the Ragon Institute of Massachusetts General Hospital, MIT and Harvard University, said.
Only a handful of mucosal vaccines have been approved for human use; the best-known example is the Sabin polio vaccine, which is given orally and absorbed in the digestive tract. There is also a flu vaccine delivered by nasal spray, and mucosal vaccines against cholera, rotavirus and typhoid fever.
To create better ways of delivering such vaccines, Irvine and his colleagues built upon a nanoparticle they developed two years ago.
The protein fragments that make up the vaccine are encased in a sphere made of several layers of lipids that are chemically "stapled" to one another, making the particles more durable inside the body.
This allows the particles to resist disintegration once they reach the lungs.
With this sturdier packaging, the protein vaccine remains in the lungs long enough for immune cells lining the surface of the lungs to grab them and deliver them to T cells.
Activating T cells is a critical step for the immune system to form a memory of the vaccine particles so it will be primed to respond again during an infection.
The research is published in the journal Science Translational Medicine.