Lipid blocks influenza infection

November 9, 2011

A natural lipid in the fluid lining the lungs inhibits influenza infections in both cell cultures and mouse models, according to researchers at National Jewish Health. These findings, combined with previous studies demonstrating effectiveness against respiratory syncytial virus, suggest that the molecule, known as POPG, may have broad antiviral activity.

"Supplemental POPG could be an important, inexpensive and novel approach for the prevention and treatment of influenza and other infections," said Dennis Voelker, PhD, Professor of Medicine, and senior author in the report, published online in the American journal of and Molecular Biology.

Influenza infects millions of people across the globe, killing 500,000 each year. Vaccines are highly effective, but must be reformulated each year to counter new . Two classes of drug are currently available to treat established influenza infections, although widespread resistance has developed against one class and is developing against the other.

Several proteins that inhibit have been identified in the fluid lining the lungs. Until recently, however, the antiviral role of POPG (palmitoyl-oleoyl-phosphatidylglycerol) has been unknown. Previous research by Dr. Voelker, Mari Numata, MD, PhD, and their colleagues demonstrated that POPG reduces inflammation in the lung and prevents infection by .

In the most recent study, the researchers looked at the ability of POPG to inhibit infection by two strains of influenza, H1N1-PR8 and H3N2. They found that POPG suppressed inflammatory responses, viral propagation and cell death normally associated with .

In mice, POPG also suppressed viral infection and replication, and markedly reduced the inflammatory response to the virus. There were no observable deleterious effects of POPG in animal behavior or histopathology.

"Lipids such as POPG, offer potential advantages over antiviral proteins, because they are less likely to elicit unwanted immune responses, are more chemically stable and less expensive to manufacture than proteins," said Dr. Numata, an instructor at National Jewish Health, and lead author on both the RSV and influenza papers. "Because POPG is effective against at least two different viruses, it also seems likely that a single mutation, which can make influenza vaccines and current drugs ineffective, is unlikely to have the same effect on POPG's action."

The researchers showed that POPG works by binding strongly to viral particles, which prevents attachment and infection of cells. This means that POPG works best if given before an infection occurs.

It has potential, however, to work after an infection has begun by inhibiting spread of the virus to uninfected cells. The success of POPG treatment after a virus infection has been established depends on keeping the lipid levels high for an extended period. At present it is difficult to maintain high levels of POPG in mice because of their rapid metabolisms and rapid respiratory rate.

"We believe POPG may prove effective both before and after an infection has occurred," said Dr. Voelker. "Our initial results suggest that it may be possible to maintain therapeutic levels in the body with a reasonable dosing scheme, and we are investigating that now."

Explore further: Researchers announce a discovery in how FluMist elicits protection

Related Stories

Researchers announce a discovery in how FluMist elicits protection

August 23, 2011
New research from the Trudeau Institute may help to explain why live attenuated influenza vaccine (LAIV), commonly known as FluMist, elicits protection. The research is published in this month's issue of Vaccine. The journal ...

Adjuvant combo shows potential for universal influenza vaccine

June 8, 2011
Researchers at National Jewish Health have discovered how to prime a second arm of the immune system to potentially boost influenza vaccine effectiveness. A combination of two adjuvants, chemicals used to boost the effectiveness ...

Recommended for you

Engineered protein treatment found to reduce obesity in mice, rats and primates

October 19, 2017
(Medical Xpress)—A team of researchers with pharmaceutical company Amgen Inc. report that an engineered version of a protein naturally found in the body caused test mice, rats and cynomolgus monkeys to lose weight. In their ...

Cancer drug found to offer promising results in treating sepsis in test mice

October 19, 2017
(Medical Xpress)—A combined team of researchers from China and the U.S. has found that a drug commonly used to treat lung cancer in humans offers a degree of protection against sepsis in test mice. In their paper published ...

New procedure enables cultivation of human brain sections in the petri dish

October 19, 2017
Researchers at the University of Tübingen have become the first to keep human brain tissue alive outside the body for several weeks. The researchers, headed by Dr. Niklas Schwarz, Dr. Henner Koch and Dr. Thomas Wuttke at ...

Study reveals key molecular link in major cell growth pathway

October 19, 2017
A team of scientists led by Whitehead Institute has uncovered a surprising molecular link that connects how cells regulate growth with how they sense and make available the nutrients required for growth. Their work, which ...

Tracing cell death pathway points to drug targets for brain damage, kidney injury, asthma

October 19, 2017
University of Pittsburgh scientists are unlocking the complexities of a recently discovered cell death process that plays a key role in health and disease, and new findings link their discovery to asthma, kidney injury and ...

Inflammation trains the skin to heal faster

October 18, 2017
Scars may fade, but the skin remembers. New research from The Rockefeller University reveals that wounds or other harmful, inflammation-provoking experiences impart long-lasting memories to stem cells residing in the skin, ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

grgfraiser
not rated yet Nov 09, 2011
i wonder if this would help against HIV and others as well?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.