DALLAS Oct. 22, 2008 The Bill and Melinda Gates Foundation announced today that it has awarded a UT Southwestern Medical Center scientist a grant to pursue innovative vaccine research.
The $100,000 grant to Dr. Ellen Vitetta, director of the Cancer Immunobiology Center at UT Southwestern, is one of 104 grants awarded in the first funding round of the Grand Challenges Explorations program, a $100 million, five-year initiative to promote innovation in global health. Additional funding of $1 million or more will be available for projects that show promise, according to the Gates Foundation.
Dr. Vitetta's work will focus on a new approach to developing "mimetic vaccines," which would be based on using synthetic molecules called peptoids to generate a protective immune response to a given pathogen. Dr. Thomas Kodadek, professor of internal medicine and an expert in peptoid chemistry, is a collaborator on the project.
Currently, vaccines are developed using dead or attenuated microbes, or bits and pieces of the infectious agent itself, as a basis for stimulating the human immune system to produce antibodies, or infection-fighting agents, against the disease. Dr. Vitetta's research group will screen thousands of peptoids for their ability to bind to pre-made monoclonal antibodies that are already known to neutralize all varieties of a given pathogen. For example, the researchers will look for peptoids that bind to antibodies that recognize structural features shared by all HIV strains.
"The key advantage to using peptoids to develop mimetic vaccines is that these vaccines would not be limited in their effectiveness to a particular strain or subspecies of a given virus, but rather recognize all viruses of each type. Furthermore huge libraries of peptoids can be made and screened," said Dr. Vitetta, who holds the Scheryle Simmons Patigian Distinguished Chair in Cancer Immunobiology.
Once promising peptoids are identified, they will be attached to "carriers" and tested in mice to determine whether they can actually elicit antibodies that neutralize the pathogen. Dr. Vitetta said the challenge and novelty of this approach is to demonstrate that these anti-peptoid antibodies can mimic those the body produces against the actual native pathogen and confer protective immunity.
"This is high-risk, high-impact research, meaning that there is a high risk of failure," Dr. Vitetta said. "But if our experiments are successful, we hope to identify peptoid mimetics that recognize all variants of HIV, and if we are extremely lucky, we will have a useful vaccine for HIV, which will have tremendous impact. Our work could also open the door for vaccines against other pathogens, such as West Nile virus, hepatitis C and influenza. Even if we fail entirely, we will gain a great deal of insight into what we need to do to make mimetic vaccines work."
|Contact: Amanda Siegfried|
UT Southwestern Medical Center