Washington: Researchers have taken a promising step toward the creation of a universal flu vaccine, one that could be produced more quickly and offer broader protection than the virus specific inoculants available today.
The approach by a team of Stanford researchers led by chemical and bioengineer James R. Swartz, who is the James H. Clark Professor in the School of Engineering, arises from a better understanding of the structure of a key protein on the surface of the flu virus, and a new process for making vaccines based on that understanding.
A flu virus is made up of different proteins. Protruding from the surface of the virus are hundreds of copies of a protein called Hemagglutinin (HA). Each copy of HA resembles a mushroom, with a head and a stem. The head of HA helps determine the virulence of a given strain of flu.
Today's vaccines are based on inactivated viruses that contain the heads of HA proteins. When a flu shot is injected into our blood stream, our immune system sees the HA head as a target, and creates antibodies to fight what appears to be an infection.
Swartz and his colleagues base their new vaccine approach on the understanding that, whereas the head of the flu virus varies from year to year, the protein stem remains more constant over time.
The Stanford study focused on the first step in developing such a universal vaccine: creating a protein stem fragment that could be injected into the blood stream, in short, creating a target, or antigen, to attract the attention of our immune system and trigger an effective defense.
The Stanford team used a relatively new and experimental process to manufacture the viral stem. This process is called cell free protein synthesis (CFPS). They used CFPS process to create and refine a viral protein stem that would be useful as an experimental vaccine antigen.
The study is published in the Proceedings of the National Academy of Sciences.