A strain of virus suitable for vaccine manufacture has now been produced and is being made available to the pharmaceutical industry and other flu laboratories.
NIBSC is one of a handful of laboratories around the world belonging to a WHO collaborative network that have been racing to produce a strain of virus suitable for manufacturing vaccine in eggs, the mainstay of influenza vaccine production.
Without suitable starting strains vaccine production on a global scale cannot begin.
The process of developing a vaccine candidate involves creating a hybrid between the strain of virus that is causing disease and a tried and tested laboratory strain. This process has been used successfully over many years both in the development of seasonal vaccine candidates and for an H5N1 bird flu vaccine strain. The idea is to make a virus that is recognised by the human body as the ‘real swine H1N1 virus’ but that is safe and easy to grow up in large quantities in vaccine manufacturing facilities.
The NIBSC team used a technique known as reverse genetics to build the new virus. This involved taking the crucial gene sequences (encoding the viral proteins recognised by the body’s immune system) from the new swine flu virus and combining them with a complementary set of gene sequences from the laboratory strain using recombinant gene technology. The resulting virus was then ‘rescued’ and tested to ensure it had the right characteristics for a swine flu vaccine.
Dr Stephen Inglis, Director of NIBSC, said:
“Our scientists have been working round the clock to develop a vaccine candidate since we received the first swine flu isolate from the USA at the beginning of May and I am delighted that they have been successful so quickly.
“The strain is now available for supply to vaccine manufacturers so that they can begin the first steps in the vaccine production process, and to other flu laboratories around the world for research.
“Our WHO network colleagues in the USA and Australia are also making good progress and we expect there soon to be a number of possible strains to use for large scale manufacture of swine flu vaccine.
“Vaccines form a very important part of the raft of public health measures that are being developed to combat the outbreak of swine flu and once available will play an important role in protecting people’s health.”
Source: Health Protection Agency, UK