Nav: Home

These less common proteins may help fend off the flu

March 12, 2019

Washington, DC - March 12, 2019 - Influenza type B, though generally less widespread than type A, poses a formidable threat for vulnerable populations like the elderly and the young. In the 2012-2013 flu season, for example, influenza type B caused the majority of deaths due to flu among children, according to data from the Centers for Disease Control and Prevention. Findings published this week in mBio, ASM's open access journal, suggest that an efficient way to boost the efficacy of vaccines against influenza type B might be hiding in plain sight.

The researchers report that neuraminidase (NA), a protein found in small amounts in current vaccines, prompts the immune system to produce antibodies that may mount a broad protective response against influenza B viruses. Previous studies have connected NA antibodies to protection against the flu - likely by preventing the spread of infection -- but this new study is among the first to show how that mechanism might be exploited for future, broad-acting flu vaccines.

"Targeting this type of vaccine response can help us develop a universal vaccine," said influenza virologist Luis Martinez-Sobrido, PhD, at the University of Rochester in New York. He co-led the study with immunologist James Kobie, PhD, also at Rochester.

Existing flu vaccines contain proteins found on flu particles. These proteins prompt the immune system to generate antibodies that find and bind proteins on the surface of infectious particles within the body. As a result, the virus loses the ability to replicate and infect other cells.

This immune response is dominated by antibodies that target a common family of proteins called hemagglutinins (HA). However, those proteins mutate at a rapid clip every year, giving rise to new seasonal flu strains that are resistant to existing vaccines.

The virus surface has only about one-fourth as many NA proteins as HAs. But NAs have a lower rate of mutation than HAs, which suggests that a flu vaccine that contains NA - prompting the immune system to produce NA antibodies -- may be effective for multiple years, said Martinez-Sobrido.

The researchers and their collaborators first studied blood samples from volunteers who, a week earlier, had received the seasonal inactivated quadrivalent flu vaccine for the 2014-2015 season. That analysis showed that the vaccine had induced the production of NA antibodies for influenza type B particles. Follow up tests and experiments led the researchers to identify and clone six specific antibodies that targeted NA on Flu B particles.

"These are broad antiviral agents that work against a wide range of Influenza B strains," said Dr. Kobie.

Experiments on human cells in the lab suggested that the agents worked by blocking the release of infectious particles. The researchers then used the agents to treat mice infected with influenza type B; their findings suggest that the antibodies can reduce the replication of the virus and have the potential to both prevent and treat infections.

Finally, the scientists studied bone marrow from one of the original human volunteers one year after vaccination. The marrow continued to produce these NA antibodies with anti-viral activity, suggesting that a vaccine strategy based on NA responses could be long-lasting.

According to the researchers, the amount of NA-specific antibodies with such broad activity stimulated by current vaccines may not be sufficient to optimally protect an individual against influenza B. The new findings suggest a way to boost that efficacy.

"Seasonal vaccines are good in protecting us against influenza," said Dr. Martinez-Sobrido, "but there is room for improvement. By tuning a vaccine to elicit more of an NA-related response like the one found in our studies, we could go further in developing a universal vaccine."
-end-
The American Society for Microbiology is the largest single life science society, composed of more than 32,000 scientists and health professionals. ASM's mission is to promote and advance the microbial sciences.

ASM advances the microbial sciences through conferences, publications, certifications and educational opportunities. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to diverse audiences.

American Society for Microbiology

Related Immune System Articles:

The immune system may explain skepticism towards immigrants
There is a strong correlation between our fear of infection and our skepticism towards immigrants.
New insights on how pathogens escape the immune system
The bacterium Salmonella enterica causes gastroenteritis in humans and is one of the leading causes of food-borne infectious diseases.
Understanding how HIV evades the immune system
Monash University (Australia) and Cardiff University (UK) researchers have come a step further in understanding how the human immunodeficiency virus (HIV) evades the immune system.
Carbs during workouts help immune system recovery
Eating carbohydrates during intense exercise helps to minimise exercise-induced immune disturbances and can aid the body's recovery, QUT research has found.
A new model for activation of the immune system
By studying a large protein (the C1 protein) with X-rays and electron microscopy, researchers from Aarhus University in Denmark have established a new model for how an important part of the innate immune system is activated.
Guards of the human immune system unraveled
Dendritic cells represent an important component of the immune system: they recognize and engulf invaders, which subsequently triggers a pathogen-specific immune response.
How our immune system targets TB
Researchers have seen, for the very first time, how the human immune system recognizes tuberculosis (TB).
How a fungus inhibits the immune system of plants
A newly discovered protein from a fungus is able to suppress the innate immune system of plants.
A new view of the immune system
Pathogen epitopes are fragments of bacterial or viral proteins. Nearly a third of all existing human epitopes consist of two different fragments.
TB tricks the body's immune system to allow it to spread
Tuberculosis tricks the immune system into attacking the body's lung tissue so the bacteria are allowed to spread to other people, new research from the University of Southampton suggests.

Related Immune System Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...