From Monash magazine, October 2014:
One of the big challenges facing health officials trying to supply, and use, vaccines in remote regions where refrigeration is either limited, unreliable or non-existent is that vital vaccines are sensitive to hot conditions.
Too often vaccines fail to provide the necessary immune protection because the refrigerated supply chain that is supposed to protect them from temperature extremes while they are being transported has broken down.
Now there is a possible life-saving solution in the unlikely form of a crystalline “life raft” built by a silkworm virus to protect its viral “weaponry” from the elements. This pathogenic material is embedded into the protein crystal that, like an armoured safe, protects it (in the soil or on leaves) until a silkworm ingests the crystal and provides the virus with a new host.
Monash University’s Dr Fasséli Coulibaly discovered this structure, which is a crystal formed from a single protein, in 2007 in collaboration with Associate Professor Peter Metcalf from the University of Auckland. Having mapped the crystal using X-ray crystallography – in itself a groundbreaking endeavour – Dr Coulibaly set out to explore what might be done with this discovery. He looked at whether the crystals could be adapted to carry other molecular payloads, such as vaccines.
Dr Coulibaly christened the crystals MicroCubes because of their resemblance to sugar cubes. Their crystalline structure sets them apart from other vaccines, and also means they act in different ways. They are able to mimic the surface of viruses by presenting a regular array of selected viral components, and for this reason he expects them to prove particularly effective. They may even, he says, enable the development of vaccines that currently do not exist – for HIV or malaria, for example, or a universal flu vaccine. Read more.