Download Faster Flu Vaccine

Faster Flu Vaccine
Researchers Apply DNA Biology to Vaccination Technique
February 1, 2006 — Spraying viral genes directly through the skin is a
new technique that turns infinitesimal amounts of DNA into an effective
vaccine. If approved for use in humans, the new procedure could save
lives in case of a flu pandemic, by skipping the current, time-consuming
production of vaccines in chicken eggs.
LONDON--A new flu vaccine could save lives and protect us from a deadly outbreak. But can the
United States handle a widespread flu epidemic? Most experts would agree -- not with the way
we currently mass-produce the vaccine. It currently takes at least six months to a year to make flu
vaccines, but that's soon to change.
We all know the signs; but what if a new, more-powerful, more-deadly strain of the flu emerges?
John Beadle, a researcher from the Infectious Disease and Oncology department at PowderMed,
Ltd. in London, says, "The traditional way of making vaccines has a number of significant
drawbacks."
The biggest drawback is the amount of time it takes to make, which is too long. This 1950's-style
vaccine process using chicken eggs takes too long, putting lives at risk if an outbreak occurs.
Now, a new vaccine based on flu virus DNA could be a faster way to fight the flu.
"DNA vaccines can be manufactured very rapidly, and they can be manufactured in large
amounts," Dr. Beadle says.
Infectious disease researchers extract just a few genes from the DNA of the flu virus to make a
vaccine. Then, microscopic particles are coated with the vaccine and shot into the body at superfast speeds using this new, needle-free device. "It's because the DNA gets into the cells of the
skin that it produces such a strong immune response," Dr. Beadle says.
A better response is important for older Americans, like 77-year old Claire Mobley. "Having had it
once, I don't want to get it again."
This new, high technology could be the solution to an old problem -- producing a vaccine in half
the time of traditional methods. Dr. Beadle says, "That means that a lot more lives can be saved
within that period if we have a pandemic."
The new DNA vaccine and new administering device for influenza is not yet FDA approved.
Human clinical trials are planned for this year to test it against the bird flu, but any mass-produced
product is still several years away. A flu outbreak or worse -- a pandemic -- could speed up the
FDA approval process and bring the vaccine closer to use.
BACKGROUND: Researchers have been working on a DNA-based vaccine for the flu for several
years. While not yet ready for widespread use, if there were a global outbreak of the potentially
deadly virus, such a vaccine could be fast-tracked into use. The Center for Disease Control
estimates that more than 200,000 people in the U.S. are hospitalized each year as a result of the
flu, and more than 30,000 die from it. Globally, the flu kills close to half a million people every
year.
HOW VACCINES WORK: There are three basic strains of the flu virus: A, B and C. A is the most
common strain, and the most severe. The flu vaccine works by triggering the body's immune
system response. The body recognizes the vaccine as a foreign invader and produces antibodies
to it. However, flu strains differ from year to year; that's why there is a different vaccine each year.
Currently, flu vaccines are made by incubating the three strains of the flu virus expected to strike
in a given year are injected into millions of chicken eggs to multiply before being extracted and
packaged. It is a labor-intensive and time-consuming technique that is much the same as when it
was first invented in the 18th century.
WHAT ARE DNA VACCINES?: DNA vaccines are a form of gene therapy in which just a few
genes are extracted from the virus and injected into people. Unlike the standard process, which
takes up to six months, DNA-based vaccines could be ready in less than three months. The
downside is they have never been tested in full-blown clinical trials.
WHAT IS THE FLU: The flu is caused by the influenza virus, which targets the respiratory tract
by binding to the surface of cells. Then the virus releases its genetic information (RNA) into the
cell's nucleus to replicate itself. When the cell dies, those copies are released into the body,
infecting other cells. Flu symptoms are unpleasant, but not life-threatening by themselves.
However, the flu weakens the immune system, making the body vulnerable to more serious
infections, such as pneumonia.
Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.
Note: This story and accompanying video were originally produced for the American Institute of
Physics seriesDiscoveries and Breakthroughs in Science by Ivanhoe Broadcast News and are
protected by copyright law. All rights reserved.
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Fast Method for Preparing Flu Vaccine: Use Bioreactors
Instead of Chicken Eggs
ScienceDaily (Dec. 9, 2009) — A shortage of flu vaccines may soon
become a problem of the past. Researcher Manon Cox has developed
an alternative process for producing large quantities of safe and
effective vaccines at twice to four times the usual speed. The process is
based on using cells in bioreactors instead of fertilised chicken eggs,
which have a limited availability.
Manon Cox will be conferred with a PhD at Wageningen University, Netherlands, on 9 December
on the strength of a thesis on this subject.
The prompt availability of sufficient suitable vaccine is always a problem when facing the
outbreak of a flu epidemic. At the moment, it takes three to six months to produce a vaccine to
counter a new strain of flu virus using chicken's eggs. Moreover, there is no possibility of
expanding production capacity in the event of a pandemic as the limited availability of fertilised
chicken's eggs needed for production inevitably becomes an insurmountable problem.
Cox's new process demonstrates that it is possible to make a vaccine available in commercial
quantities within 45 days. The new production method makes use of a baculovirus that multiplies
only inside insect cells, and which cannot spread in vertebrates. The insect cells produce huge
quantities of so-called HA proteins, which mobilise the immune system into fighting the flu virus.
The aspect that most slows down the production of vaccine according to the conventional method
is the need for fertilised chicken eggs. Furthermore, this creates extra problems if the flu virus is
also capable of infecting birds (as was the case in the Netherlands in 2003), as the egg
production often grinds to a halt. In addition, the vaccines produced are not suitable for people
with an egg allergy. The new production process using insect cells can be used on a large scale,
at all times and simultaneously at various locations throughout the world. The process can easily
be adapted to new influenza strains and enhance pandemic preparedness.
Meanwhile, the new production process has already been put through clinical trials involving
three different strains of flu virus in 460 healthy people. None of the test subjects injected with the
vaccine developed symptoms of flu, while 4.6% of those taking part in the control group
contracted the disease naturally. Three follow-on studies involving approximately 3,000 people
showed no striking or frequent side-effects. The vaccine also appears to protect people from
influenza viruses that have undergone genetic changes and in more than 50% of cases, it results
in better antibody production than the flu vaccines currently available.
Vaccines for the flu virus contain the HA protein (haemagglutinin) which, once in the bloodstream,
puts the body in a state of high alert. The protein also stimulates the production of flu-specific
antibodies. The same protein is found on the surface of a flu virus. When a vaccinated person
encounters a flu virus , the antibodies produced attach to the proteins on the surface of the virus
and inactivate the virus.
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Producing Flu Vaccines Will Be Faster And Cheaper, Thanks
To MSU Technology
ScienceDaily (July 10, 2006) — Technology from Michigan State animal
science labs looks to produce new human flu vaccines quicker and
cheaper than current methods.
While studying new techniques to produce vaccines for Marek's disease, a common chicken
disease that causes big losses for poultry producers, Paul Coussens, MSU professor of animal
science and microbiology and molecular genetics, and his colleagues found a cell line that had
intriguing potential for growing flu virus – a change from the fertilized chicken eggs that are now
used to grow the virus strains for vaccines.
HepaLife Technologies Inc., a biotechnology company based in Vancouver, has licensed the
technology from MSU and plans to produce cell culture-based flu vaccine.
"We want to proceed as quickly as possible," said Harmel Rayat, president of HepaLife. "There's
no time to waste. Sooner or later the avian flu virus will be in North America. It's not if, it's when."
"The recent highly virulent avian flu cases in Asia and fears about a pandemic have highlighted
the problems with traditional influenza vaccine production methods, particularly the length of time
to produce a new vaccine and the amount of vaccine that can be produced on short notice," said
Coussens, who also is the director of the MSU Center for Animal Functional Genomics.
Building on work done by graduate student Amin Abujoub and assistant professor David Reilly,
Coussens and his collaborators found the cell line would grow almost every type of flu virus:
avian, swine, equine and human. In cell culture-based vaccine production, scientists infect cells
with flu strains. Then they grow the virus in large vats or bioreactors. The virus is killed and
purified to make the vaccine.
Growing virus in cell culture could dramatically speed up vaccine production. For the past 50
years, flu vaccines have been made by injecting 11-day-old fertilized chicken eggs with a flu virus
strain. The virus grows in the eggs and is then killed and purified to make the vaccine. Each egg
is injected with only one virus strain (a typical flu vaccine contains three strains) and produces
enough virus for one or two doses.
This means that huge numbers of fertilized chicken eggs are needed – 270 million or more – to
produce a sufficient vaccine supply for the United States. The process is time consuming and
inflexible because vaccine makers have to order eggs months ahead of time. If there are any
problems with the eggs, such as infection by another virus, the entire lot of flu vaccine is lost.
Plus, anyone with an egg allergy can't have the vaccine.
"By growing cell culture-based flu virus, the cost and the time needed to produce the vaccine will
be much lower," Coussens said. "We'll also be able to produce much more vaccine in a smaller
space. And the virus that is grown is more pure. People with allergies to eggs are likely to benefit
the most because they'll be able to have flu shots without the threat of allergic complications."
Influenza Vaccines of the Future
ScienceDaily (Nov. 17, 2010) — In a review article appearing in
the New England Journal of Medicine, scientists at the National Institute
of Allergy and Infectious Diseases (NIAID), part of the National Institutes
of Health, examine research under way to address the limitations of
currently available influenza vaccines and develop more efficient and
reliable strategies to make vaccines to protect against seasonal as well
as pandemic influenza.
Although licensed seasonal flu vaccines safely and effectively protect most people who receive
them from illness and death, the degree of protection varies depending on how well the
circulating virus strains and those in the vaccine match. A vaccine recipient's age and health
status also can affect the effectiveness of influenza vaccination.
The authors discuss the spectrum of ongoing influenza vaccine research that may transform the
field in decades to come. Efforts to grow the vaccine virus in cells rather than eggs are currently
under way and there is consideration of the addition to influenza vaccine of immune-stimulating
adjuvants to be used in certain groups of individuals. Other approaches under development
include influenza vaccines based on recombinant virus proteins, non-infectious virus-like
particles, harmless vectors or influenza DNA. Also under intense study is the ultimate goal, a socalled universal flu vaccine that would provide protection against multiple strains of influenza,
reducing the need for yearly flu shots while simultaneously protecting against novel flu viruses
that may arise in the future.
To further protect vulnerable populations such as the elderly and those with underlying chronic
diseases from seasonal influenza, as well as to quickly control the spread of potential pandemic
influenza viruses, influenza vaccine makers of the future must employ novel production
technologies, the authors
Coussens' research is supported by the U.S. Department of Agriculture and the Michigan
Agricultural Experiment Station.
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