An advanced approach to vaccine design could be useful against highly variable viruses that have been difficult to stop using traditional strategies.
Philip R. Johnson, MD, The Children's Hospital of Philadelphia Research Institute's chief scientific officer, is among the co-authors of a study published in Nature that offers proof-of-principle that a new software application, "Fold from Loops," can custom design artificial proteins as vaccine components.
Most existing vaccines use inactivated viruses or similar particles to stimulate the body's immune system to release infection-fighting antibodies; however, rapidly evolving infectious agents such as HIV can evade traditional vaccine candidates. As a result, vaccine experts have been working to develop next generation vaccines that elicit broadly neutralizing antibodies to strike against hidden vulnerable structures within quick-changing viruses.
The new strategy uses sophisticated techniques to imitate an epitope - a structure specific to each type of invading virus that is recognized by the immune system. "Fold from Loops" designs flexible protein scaffolds to hold the epitope that induces the immune system to produce protective antibodies.
In the Nature study, a research team led by William R. Schief, PhD, and colleagues from The Scripps Research Institute in La Jolla, Calif., induced potent antibodies in non-human primates against respiratory syncytial virus (RSV), a serious childhood infection. The successful experiment demonstrates that this approach is feasible for developing a first RSV vaccine in humans, as well as for accelerating the creation of new vaccines against difficult-to-treat diseases such as HIV, influenza, and hepatitis C.
"Bringing these new types of vaccines into clinical use will take years of work, but this study represents an important first step along the way," Dr. Johnson said.