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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. Ads by Google Advertise here 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. Recommend this story on Facebook, Twitter, 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. Recommend this story on Facebook, Twitter, and Google +1