Nanoparticle to optimise vaccines

Scientists have developed synthetic nanoparticles capable of mimicking part of the body’s immune system, which they say could help optimise vaccine responses and also lead to developing customised vaccines.

The tiny capsules, created by researchers from the Duke University in the US, are able to encourage the body to accept vaccines against illnesses and infections. After successfully testing the new nanoparticles on mice, the researchers are now hoping they could soon be suitable for humans, the BBC reported.

In their study, published in journal Nature Materials, the Duke team aimed to hijack a natural immune response involving cells called mast cells found in the skin. These cells are a key part of the driving force behind the itching and swelling during an allergic reaction, but are also thought to play a role in the “innate immune system”, which reacts to infection.

It is believed that when they encounter certain bacteria and viruses, they release small capsules called “granules”, which contain a body chemical, called tumour necrosis factor (TNF), which travel to nearby lymph nodes, where the immune response to the infection can begin to be mobilised.

The researchers produced their own granule, also carrying TNF, designed to behave in the same way. When injected at the same time as the vaccine, they are set up to travel to the lymph node and release the chemical, as if sent by an activated mast cell, and hopefully producing a more powerful immune response to the vaccine contents.

To test this, they vaccinated mice against influenza A, adding the nanoparticle “granules”. When exposed to a level of the virus which would normally prove lethal, the vaccinated mice had an improved survival rate.

The researchers said it would be possible to add different immune system chemicals to the nanoparticles to tailor the response to exactly the type of vaccine involved. Dr Soman Abraham, who led the research, said that the individual chemicals used were already approved for use in humans in the US.

He said: “There is a lot of interest in anoparticle-based therapy, but we are basing our materials on our observation of mast cells in nature. “This is an informed application to deliver the right material to the right place in the body to get the most effective immune reaction.”