Researchers strike gold with nanotech vaccine

Scientists in the US have developed a novel vaccination method that uses tiny gold particles to mimic a virus and carry specific proteins to the body's specialist immune cells.

The technique differs from the traditional approach of using dead or inactive viruses as a vaccine and was demonstrated in the lab using a specific protein that sits on the surface of the respiratory syncytial virus (RSV). The results have been published today, 26 June, in IOP Publishing's journal Nanotechnology by a team of researchers from Vanderbilt University.

RSV is the leading viral cause of lower respiration tract infections, causing several hundred thousand deaths and an estimated 65 million infections a year, mainly in children and the elderly. The detrimental effects of RSV come, in part, from a specific protein, called the F protein, which coats the surface of the virus. The protein enables the virus to enter into the cytoplasm of cells and also causes cells to stick together, making the virus harder to eliminate.

The body's natural defence to RSV is therefore directed at the F protein; however, up until now, researchers have had difficulty creating a vaccine that delivers the F protein to the specialised immune cells in the body. If successful, the F protein could trigger an immune response which the body could 'remember' if a subject became infected with the real virus.

In this study the researchers created exceptionally small gold nanorods, just 21 nanometres wide and 57 nanometres long, which were almost exactly the same shape and size as the virus itself. The gold nanorods were successfully coated with the RSV F proteins and were bonded strongly thanks to the unique physical and chemical properties of the nanorods themselves. The researchers then tested the ability of the gold nanorods to deliver the F protein to specific immune cells, known as dendritic cells, which were taken from adult blood samples.