Even with vaccines, 20-40 million people in the United States catch the flu each year, and thousands are at risk of dying from its complications.
In the future, a new class of prescription drugs called neuraminidase inhibitors offers the prospect for decreasing the duration and severity of the illness and may even prevent the development of symptoms in those exposed to the virus. One of these neuraminidase inhibitors was developed through ground and space research conducted in partnership by NASA and the Center for Macromolecular Crystallography at the University of Alabama at Birmingham.
The compound was synthesized by BioCryst Pharmaceuticals in Birmingham, Ala., and is now under development by The R.W. Johnson Pharmaceutical Research Institute in Raritan, N.J., a Johnson & Johnson company.
"With the aid of NASA support for space and ground-based research, we successfully mapped the molecular structure of the influenza virus -- exposing its weaknesses," said Dr. Larry DeLucas, director of the Center for Macromolecular Crystallography at the University of Alabama at Birmingham.
Sponsored by the Space Product Development Office of NASA's Microgravity Research Program at the Marshall Space Flight Center in Huntsville, Ala., DeLucas' organization is chartered as a NASA Commercial Space Center -- encouraging private industry to benefit from space technology. Dr. Ming Luo, a professor of the Center for Macromolecular Crystallography, and an international team of crystallographers, developed the "molecular map" of the flu virus using space-grown protein crystals.
Influenza protein crystals flown aboard Space Shuttle mission STS-77 in May 1996 were used to confirm earlier studies and to determine the effectiveness of potential drugs on the flu virus protein.
"By analyzing space-grown crystals of the influenza virus, we were able to get a clearer picture of the virus' structure," said DeLucas. "NASA's support for this research project probably saved considerable time needed to develop this new drug."
Called "structure-based drug design," this research focuses on how molecules of a virus fit together. Researchers built diagrams of the flu's unique shape to design drugs that block the undesirable characteristics of the virus.
Neuraminidase inhibitors are designed to block an active site of influenza neuraminidase, an enzyme associated with the spread of the flu. Unlike vaccines, which have to be taken before exposure and are only specific to certain strains of the influenza virus, neuraminidase inhibitors may be taken as either treatment or prevention, and are effective against a wide variety of influenza strains.
"It's like trying to build a tiny key that fits into a tiny lock," said DeLucas. "Except this lock is living, breathing, flexing, changing temperatures and in constant motion."
The R.W. Johnson Pharmaceutical Research Institute is responsible for all phases of testing the drug in humans. Before becoming available in the U.S., the drug must undergo this testing and be approved by the Food and Drug Administration.
Pure, precisely ordered protein crystals of large size and uniformity are in high demand by drug developers for efforts such as this flu research. When grown on the ground, protein crystals often cannot be grown as large or as well ordered as researchers desire, obscuring these vital pathways to a better understanding of disease. As the "frequent flyers" of the space program, protein crystal growth experiments are aboard nearly every Space Shuttle mission, helping researchers unlock the secrets of how to stop infection and disease on Earth.
Space research has provided important advances in the understanding of many diseases, including heart disease, cancer, diabetes, respiratory syncytial virus and hepatitis.
Note to Editors: Interviews are available with NASA, industry and university
researchers by contacting Steve Roy of the Marshall Center Media Relations
Office at 256-544-6535. More information about NASA's Microgravity Research
Program experiments can be found at:
http://www.msfc.nasa.gov/news
and
http://microgravity.msfc.nasa.gov
Photos: Contact Steve Roy to receive the three available photos or download
print-quality images from the web at:
http://www1.msfc.nasa.gov/NEWSROOM/news/photos/1999/photos99-040.htm
#9901148 (Flu Diagram) Mapping a Disease Brings Hope for Relief from the Flu
Developed from flu crystals grown in space, a computer model shows where a new drug (in yellow and purple) may be attached to the flu virus to stop it from spreading.
#9901150 (Luo with model) Fighting the Flu with Help from Space
Because of the increased size and perfection of space-grown crystals of the flu virus, Dr. Ming Luo, associate director of the Center for Macromolecular Crystallography of the University of Alabama at Birmingham, has designed a molecular model of a new anti-flu drug.
#9901149 (Luo with crystals) Space Crystals May Help Fight the Flu
By X-raying flu virus crystals grown in space, Dr. Ming Luo, associate director of the Center for Macromolecular Crystallography located at the University of Alabama at Birmingham, is able to map the flu's structure for drug developers.