Nanoparticle Vaccine

Many viruses and bacteria infect humans through mucosal surfaces, such as those in the lungs, gastrointestinal tract and reproductive tract. To help fight these pathogens, MIT scientists 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. According to Darrell Irvine “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” He is also exploring use of the particles to deliver cancer vaccines.                          

This nanoparticle was built by Irvine and his colleagues 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 particles also hold promise for delivering cancer vaccines, which stimulate the body's own immune system to destroy tumors. To test this, the researchers first implanted the mice with melanoma tumors that were engineered to express ovalbumin, a protein found in egg whites. Three days later, they vaccinated the mice with ovalbumin. They found that mice given the nanoparticle form of the vaccine completely rejected the tumors, while mice given the uncoated vaccine did not.

The MIT scientists keep working on the development of this nanoparticle vaccine in order to use it to cure some other sickness.

 

Nanoparticle Vaccine