A seasonal flu shot is a bit like a local weather forecast: Based on the conditions elsewhere and the direction of the prevailing wind, a meteorologist can give the public a pretty good idea of what to expect in the near future. Experts who track influenza’s intercontinental travels basically do the same thing.
“Epidemiologists monitor what strains of influenza are circulating in Southeast Asia. … they usually choose three or four of them, and they predict what the prevailing circulating strains will be,” said David Putnam, associate professor in the Nancy E. and Peter C. Meinig School of Biomedical Engineering.
“Usually they’re right, but sometimes they’re wrong,” Putnam said, “and it changes every year because proteins in the virus mutate.”
But certain proteins in the influenza virus remain constant year after year. And Putnam and Matt DeLisa, the William L. Lewis Professor of Engineering in the Robert Frederick Smith School of Chemical and Biomolecular Engineering, are taking one of those conserved proteins, Matrix-2 (M2), and packaging it in a nanoscale, controlled-release “capsule” in an attempt to create a quick-acting, long-lasting, multi-strain vaccine against pandemic influenza A.
The capsule is a bacterial outer membrane vesicle (OMV), which DeLisa and Putnam have developed collaboratively for several years. The OMV is a membrane-based nanostructure, in this case engineered from nonpathogenic E. coli, whose outer surface mimics the cell from which it originated.
Their paper, “A Single Dose and Long-Lasting Vaccine Against Pandemic Influenza Through the Controlled Release of a Heterospecies Tandem M2 Sequence Embedded Within Detoxified Bacterial Outer Membrane Vesicles,” appears in the journal Vaccine. First author is Hannah Watkins, Ph.D. ’17, now a postdoctoral researcher at the Massachusetts Institute of Technology.
The influenza A virus is a moving target. It changes year to year, and can morph into a pandemic – infectious across a large region – strain that can put the general population at risk. The Putnam-DeLisa team is leveraging the versatility of OMVs, which have shown promise against other deadly pathogens, to create a single-shot vaccine.
The M2 protein is found evolutionarily in the influenza sequence in birds, pigs and humans, so the group took two sequences from birds, one from pigs and one from humans, and assembled them into one multitarget antigen.
“So even if, say, the human strain mutates,” Putnam said, “we know where it came from and it’s going to look like the other two. We kind of covered all the bases.”
In testing, mice infected with the influenza A virus developed high antibody counts just four weeks after vaccination, compared with eight weeks from a typical multishot (prime/boost) vaccine regimen. And the protection was long-lasting: After six months, all of the test mice given the OMV vaccine survived a lethal influenza A infection.
Six months is approximately 25 percent of the typical life expectancy for a mouse, so Putnam thinks it is likely that this OMV-based vaccine would be long-lasting for humans, too.
“Even if we have to give a booster shot every 10 years, like tetanus, that’s still very good,” he said. “Theoretically it should last a long time.”
Additionally, since the vaccine cocktail is encapsulated in a bacterial vesicle, there’s no need for an adjuvant – an agent that’s added to most vaccines to boost the body’s immune response. The immune response is enhanced by the bacteria from which the OMV is derived.
“As a result, formulating and manufacturing of controlled-release OMVs should be more cost-effective,” DeLisa said.
Learn more: A new kind of influenza vaccine: One shot might do the trick
The Latest on: Multi-strain flu vaccine
[google_news title=”” keyword=”multi-strain flu vaccine” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]- Longhorn Vaccines and Diagnostics Presents New Data on its Best-In-Class Infectious Disease Vaccine and Antibody Portfolio at ECCMID 2024on April 27, 2024 at 5:01 am
Longhorn Vaccines and Diagnostics, a One Health company developing vaccines and diagnostic tools for global public health and zoonosis concerns, presented positive data from three key studies of its ...
- Cidara Therapeutics: Now Well-Funded To Advance Its Cloudbreak Platformon April 26, 2024 at 3:02 pm
Cidara Therapeutics, Inc. secures funding and focuses on oncology platform after passing rezafungin rights to Mundipharma. Learn more about CDTX stock here.
- Bird flu in cattle: A step closer to humans or a random event?on April 26, 2024 at 12:03 pm
Scientists have kept a wary eye on H5N1 bird flu as the virus has swept around the world in recent years, infecting numerous mammalian species along the way. Now the virus has been found in US cattle.
- What to know about avian influenza in dairy cows and the risk to humanson April 26, 2024 at 5:36 am
Why is H5N1, or bird flu, a concern, how does it spread, and is there a vaccine? Here are the answers to some frequently asked questions about avian influenza.
- Vaccine breakthrough means no more chasing strainson April 25, 2024 at 11:10 am
Scientists at UC Riverside have devised a vaccine that targets a part of the viral genome that is common to all strains of a given virus.
- Massive amounts of H5N1 vaccine would be needed if there’s a bird flu pandemic. Can we make enough?on April 24, 2024 at 10:53 am
The first signs that H5N1 avian flu was starting to spread from person to person would trigger a race to produce massive amounts of vaccine.
- DOH told to expedite flu immunization campaign for seniors to prevent outbreakson April 24, 2024 at 9:04 am
Over the past year, the Philippines witnessed a staggering 45 percent surge in cases of influenza-like illnesses (ILI), indicating a notable uptick in respiratory diseases. This poses a significant ...
- Is There a Vaccine for H5N1 Influenza?on April 22, 2024 at 2:31 pm
On the heels of a multi-state outbreak of highly pathogenic avian influenza A (H5N1) in dairy cows, experts told MedPage Today that a trio of H5N1 vaccines for humans has already been developed and ...
- WHO's top scientist sounds alarm about bird flu and need for vaccine developmenton April 19, 2024 at 3:31 pm
The WHO we should be taking action to prevent bird flu. U.S. health officials say the country is ready to ramp up vaccine production.
- Genetics-based universal vaccine could be effective against any viral strainon April 16, 2024 at 7:32 am
Genetics-based "one-and-done" vaccines for the flu and COVID-19 could prove more effective and easier to craft than current jabs, researchers report.
via Google News and Bing News