Insect cells provide the key to alternative swine flu vaccination

"Recent outbreaks of influenza highlight the importance of a rapid and sufficient vaccine supply for pandemic and inter pandemic strains," said co-author Florian Krammer from the University of Natural Resources and Applied Life Science in Vienna. "However, classical manufacturing methods for vaccines fail to satisfy this demand."

Traditional influenza vaccines, which are produced in embryonated chicken eggs, can be manufactured in the quantities needed for seasonal strains of influenza. Yet because of limited egg supply this method may be insufficient in a pandemic scenario, such as the current H1N1 'swine flu' pandemic.

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 weeks to produce swine-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 months.

Using insect cells also bypasses the disadvantages of egg-based production, such as limited production capacity, allergic reactions to egg proteins and biosafety issues.

"Our work demonstrates that recombinant influenza virus-like particles are 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 Krammer.

"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."