Flu Jab for Life' on the Horizon

Research Groups – With Stable Injection Solution – H1N1 Stalk Protein

Online magazines reports that two research groups have come up with a stable, injectable solution comprising of H1N1stalk protein known as hemagglutinin. It has two main components, namely the head – the portion of the virus which mutates and changes from strain to strain and the stem which is same across several flu strains. The groups made attempts in removing the variable head region and kept the stem as the base of their vaccines.

However, hemagglutinin seems to be quite feeble. Once it is beheaded, the stem tends to fall apart and the antibodies cannot bind it any longer. The team tried various approaches in order to anchor the headless stem. Researchers in Nature Medicine utilised a two-step method by introducing a combination of mutations to stabilise the core of the hemagglutinin stem.

 Thereafter they bound bacteria-derived nanoparticles to the stem that drew the subunits of the protein together to hold it in the appropriate position. The other team applied a combination of mutations which realigned the subunits of the stem above. This was adequate in sustaining a practical construction for the vaccine.

Operates By Carrying Huge Globular `Decoy’ Proteins

The flu virus operates by carrying huge globular `decoy’, proteins to entice the attention of the human immune system wherein these decoys are put in the flu vaccines to prepare our immune system for any possible attack.

However, as the name suggests, these proteins tend to mutate and shapes-shifts and thus the body fails to recognise them after some years. Nevertheless, waiting below these devious decoy, are `stalk’ proteins which are much more structural stable protein which are responsible in replicating and infecting the body. These stalk proteins have proved to be tricky to engineer in a lab till date. Both the vaccines though have gained mixed results in animal trials.

The first group from the Netherlands based Crucell Vaccine Institute and the Scripps Research Institute in California, immunized mice against lethal doses of the H1N1 flue and H5N1 bird flu. However in the case of monkeys, it only helped in reducing the fever which was due to low doses of H1N1.

Stable/Safe Though Not Strong

The second group from the Maryland based National Institutes of Health activated immune responses from tested ferrets and rats but found that only four of the six ferrets survived and their immune system reactions were presumed to be closer to humans.

The vaccine, in other works though being stable and safe to administer is not strong enough in preventing animals coming down with flu. Inspite of it all, the experts are of the belief that the breakthrough could indicate that a universal flu vaccine is in the pipeline. John Oxford Virologist, from the University of London has commented that `this is a leap forward when compared to anything ever done in recent times. They have good animal data and not only in mice but in ferrets as well as monkeys.

 They have also done it with the bird flu virus H5N1 whichseems to be a good improvement. The experimental designs seemed to be different though the end results seem very similar and highly complementary’, according to co-author on the Science paper and structural and computational biologist at the Scripps Research Institute in San Diego, Ian Wilson. ‘It is a promising first step and very exciting to see the success of this research’. Writers of both the studies state that the next step would be in expanding protection to other strains of influenza, like H3 and H7.