Man’s best friend: Common canine virus may lead to new vaccines for deadly human diseases

Public Affairs News Service

Tuesday, Nov. 27, 2012

Writer: James  E.  Hataway, 706/542-5222, jhataway@uga.edu Contact: Biao He, 706/542-2855, bhe@uga.edu

Athens, Ga. – Researchers at the University of Georgia have discovered that a virus commonly found in dogs may serve as the foundation for the next great breakthrough in human vaccine development.

Although harmless in humans, parainfluenza virus 5, or PIV5, is thought to contribute to upper respiratory infections in dogs, and it is a common target for canine vaccines designed to prevent kennel cough. In a paper published recently in PLOS ONE, researchers describe how this virus could be used in humans to protect against diseases that have eluded vaccine efforts for decades.

“We can use this virus as a vector for all kinds of pathogens that are difficult to vaccinate against,” said Biao He, the study’s principal investigator and professor of infectious diseases in UGA’s College of Veterinary Medicine. “We have developed a very strong H5N1 flu vaccine with this technique, but we are also working on vaccines for HIV, tuberculosis and malaria.”

PIV5 does not cause disease in humans, as our immune system is able to recognize and destroy it. By placing antigens from other viruses or parasites inside PIV5, it effectively becomes a delivery vehicle that exposes the human immune system to important pathogens and allows it to create the antibodies that will protect against future infection.

This approach not only ensures full exposure to the vaccine but also is much safer because it does not require the use of attenuated, or weakened, pathogens. For example, an HIV vaccine delivered by PIV5 would contain only those parts of the HIV virus necessary to create immunity, making it impossible to contract the disease from the vaccine.

“Safety is always our number one concern,” said He, who is also a Georgia Research Alliance distinguished investigator and member of the Faculty of Infectious Diseases. “PIV5 makes it much easier to vaccinate without having to use live pathogens.”

Using viruses as a delivery mechanism for vaccines is not a new technique, but previous efforts have been fraught with difficulty. If humans or animals already possess a strong immunity to the virus used for delivery, the vaccine is unlikely to work, as it will be destroyed by the immune system too quickly.

“Pre-existing immunity to viruses is the main reason most of these vaccines fail,” He said.

But in this latest study, He and his colleagues demonstrate that immunity to PIV5 does not limit its effectiveness as a vaccine delivery mechanism, even though many animals-including humans- already carry antibodies against it.

In their experiments, the researchers found that a single dose inoculation using PIV5 protected mice from the influenza strain that causes seasonal flu. Another single dose experimental vaccine also protected mice from the highly pathogenic and deadly H5N1 virus commonly known as bird flu.

This recent work is a culmination of more than fifteen years of research and experimentation with the PIV5 virus, and He has confidence that it will serve as an excellent foundation for vaccines to treat diseases in both animals and humans.

“I believe we have the best H5N1 vaccine candidate in existence,” He said. “But we have also opened up a big field for a host of new vaccines.”

UGA Faculty of Infectious Diseases The University of Georgia Faculty of Infectious Diseases was created in 2007 to address existing and emerging infectious disease threats more effectively by integrating multidisciplinary research in animal, human and ecosystem health. Researchers from across the university focus on epidemiology, host-pathogen interactions, the evolution of infectious diseases, disease surveillance and predictors and the development of countermeasures such as vaccines, therapeutics and diagnostics. For more information about the Faculty of Infectious Diseases, see fid.ovpr.uga.edu.

UGA College of Veterinary Medicine The UGA College of Veterinary Medicine, founded in 1946, is dedicated to training future veterinarians, to conducting research related to animal and human diseases, and to providing veterinary services for animals and their owners. Research efforts are aimed at enhancing the quality of life for animals and people, improving the productivity of poultry and livestock, and preserving a healthy interface between wildlife and people in the environment they share. The college enrolls 102 students each fall out of more than 800 who apply.

Gargle with sugar water to boost self control

Sugar boosts self-control, UGA study says

Wednesday, Nov. 7, 2012

Writer: April Reese Sorrow, 706 / 542-7991, aprilr@uga.edu

Athens, Ga. – To boost self-control, gargle sugar water. According to a study co-authored by University of Georgia professor of psychology Leonard Martin published Oct. 22 in Psychological Science, a mouth rinse with glucose improves self-control.

His study looked at 51 students who performed two tasks to test self-control. The first task, which has shown to deplete self-control, was the meticulous crossing out of Es on a page from a statistics book. Then, participants performed what is known as the Stroop task where they were asked to identify the color of various words flashed on a screen, which spell out the names of other colors. The Stroop task’s goal is to turn off the student’s tendency to read the words and instead see the colors.

Half of the students rinsed their mouths with lemonade sweetened with sugar while performing the Stroop test, the other half with Splenda-sweetened lemonade. Students who rinsed with sugar, rather than artificial sweetener, were significantly faster at responding to the color rather than the word.

“Researchers used to think you had to drink the glucose and get it into your body to give you the energy to (have) self control,” Martin said. “After this trial, it seems that glucose stimulates the simple carbohydrate sensors on the tongue. This, in turn, signals the motivational centers of the brain where our self-related goals are represented. These signals tell your body to pay attention.”

It took subjects about 3-5 minutes to perform the Stroop test. Martin said results show a measure of self-control, but a glucose mouthwash might not be enough to solve some of the biggest self-control obstacles like losing weight or smoking.

“The research is not clear yet on the effects of swishing with glucose on long-term self-control,” he said. “So, if you are trying to quit smoking, a swish of lemonade may not be the total cure, but it certainly could help you in the short run.”

Martin, in collaboration with co-author Matthew Sanders, a doctoral candidate also in the UGA Franklin College of Arts and Sciences, believes the motivation comes in the form of self-values, or emotive investment.

“It is the self-investment,” Martin said. “It doesn’t just crank up your energy, but it cranks up your personal investment in what you are doing. Clicking into the things that are important to you makes those self-related goals salient.”

They theorized that the glucose causes emotive enhancement, leading the person to pay attention to their goals and perform better at evoking the non-dominant response.

“The glucose seems to be good at getting you to stop an automatic response such as reading the words in the Stroop task and to substitute the second harder one in its place such as saying the color the word is printed in,” he said. “It can enhance emotive investment and self-relevant goals.”

Previous self-control studies showed a marked decrease in performance for the second task.

“Previous studies suggest the first task requires so much energy, you just don’t have the energy left for the second task that you need,” Martin said. “We are saying when people engage in self-control, they ignore important aspects of their goals and feelings. If you have to stay late at work, for example, but you really want to be going home, you have to ignore your desire to go home. Doing so will help you stay late at work, but it may also put you out of touch with what you personally want and feel on later tasks. Swishing glucose can focus you back on those goals and feelings and this, in turn, can help you perform better on the second task. In short, we believe self-control goes away because people send away, not because they don’t have energy. People turn it off on purpose.”

Martin’s research focused on what the affects of swishing glucose psychologically rather than physiologically. “We think it makes your self-related goals come to mind,” he said.

Martin’s lab is continuing to study how subjects evoke and interpret emotive responses.