Prior to the first vaccine against Poliomyelitis developed by Jonas Salk in the 1950s, the United States was plagued by tens of thousands of polio cases each year. Though the number of cases around the globe has dwindled to just 413 in 2014, the fight is not over. Due to the incredible virulence of poliovirus, it is recommended for all children worldwide to be vaccinated until global eradication is reached. A new synthetic vaccine could be the answer to finally eradicating this disease, but there is still much work to be done before it can be utilized. The technology that is being used to develop the vaccine was described by Dave Stuart of Oxford University last week at the meeting for the American Association for the Advancement of Science in San Diego, California.
Rather than contain a weakened form of poliovirus, as has been used in the traditional vaccine, the synthetic vaccine would not contain any genetic information of the virus at all. Instead, it would merely resemble the outer structure of the virus, evoking the same immune response. Eradication could finally be within reach, as this type of vaccine would be faster, easier, and safer to manufacture than the traditional vaccine.
"Using a combination of techniques, including X-ray crystallography at Diamond [Light Source] and electron cryo-microscopy in Oxford, we've begun the task of gathering crystal structures and electron microscopy images that will tell us what we need to know to stabilize the shell of the virus and engineer a strong vaccine that has the ability to bring about the desired immune response in humans,” Stuart explained to the audience.
Using weakened forms of a virus for traditional inoculation purposes can sometimes lead to circulating vaccine-derived poliovirus (cVDPV) among populations that have low vaccination rates. Though this effect is quite rare, eliminating the possibility entirely through the use of a synthetic vaccine might assuage reservations some may have in giving the vaccine to their children. Additionally, the synthetic vaccine will allow researchers to explore biological processes in greater detail. The information learned in this manner can be adapted to create new methods of treatment for other diseases as well.
"Using the latest technology, we can engineer vaccines that are billions of times smaller than a pinhead, we can track viruses as they interact with living cells, and we can glean the detailed information required to look at pathogens and then design better therapies against them. At the same time, out in the field, we can have DNA sequencers that can aid gene sequencing and help speed up the process of designing new synthetic vaccines with the added advantage of not having to send deadly virus samples around the world,” Stuart concluded.