The recent outbreak of swine flu has raised the need for rapid and efficient supply of vaccines for pandemic and inter pandemic strains.However traditions modes of vaccine production fail to meet this demand. Flu vaccines were first prepared from viruses grown in embryonated eggs. Embryonated eggs are still used today because they are inexpensive, simple, reliable and have minimal side effects or dangers for immunization. The typical flu vaccine contains three current, or expected, epidemic or pandemic flu strains. Each strain is rapidly produced or cultivated in embryonated eggs. Viruses are harvested and used to inoculate more eggs. The viruses are checked for purity and strain characteristics. Viruses are harvested and separated out from most of the egg material. Viruses are killed and combined. Vaccines are tested for sterility and effectiveness. They are then ready for injection into vacinees.
But this traditional vaccine can be manufactured in the quantities needed for seasonal strains of influenza only.It also has disadvantages like limited production capacity due to limited supply of eggs, , allergic reactions to egg proteins and biosafety issues.
Scientists in Vienna aim to overcome all these drawbacks through a new technique involving insect cells. The team’s new method turns to insect cell based technology to create recombinant influenza virus-like particles (VLPs), which resemble virus particles but lack the viral nucleic acid, so they are not infectious.The Austrian team took just ten origin pandemic H1N1 influenza VLPs for immunological study in mice. This shows that production of a mock-up vaccine is feasible in this time range, outcompeting conventional production methods which take weeks to produce swine- months.These recombinant influenza virus-like particles proves to be a very fast, safe and efficient alternative to conventional influenza vaccines and represents a significant new approach for newly emerging influenza strains like swine-origin H1N1 or H5N1″ concluded Florian Krammer from the University of Natural Resources and Applied Life Science in Vienna.
“Virus-like particles will be one solution to tackle the biological variability of influenza pandemics,” said journal editor Professor Alois Jungbauer. “Mutated strains can be quickly engineered. So in this respect the teams’ work is an extremely valuable contribution to modern vaccine production.”