Across my desk today at CABI, came the New England Journal of Medicine (NEJM) and tucked away at the back in a section called “Clinical Implications of Basic Research” was “Stalking influenza diversity with a universal antibody” by Charles R. Russell (St Jude Children’s Hospital, Memphis).
Here I learnt that an antibody has been isolated which recognizes all 16 hemagglutinin (HA) subtypes of influenza (H1 to H16), and will protect mice and ferrets from dying from the infection. Simplistically called F16 (!), it was isolated from human blood plasma cells (104,000 cells from 8 donors) by selecting for those cells that produced an antibody binding to 3 very diverse influenza strains: H1N1 (swine-origin) , H5N1 and H7N7 (both are highly pathogenic avian-influenzas). (Light dawns, yes, that’s what the H numbers mean…)
I am sure you remember the pandemic fears caused by bird-flu and swine-flu, and are familiar with the annual flu-jabs for seasonal influenza. So the significance of an antibody that can bind all 3 will not be lost on you.
The HA protein of influenza has a head and stalk structure, with the head exposed and the stalk tethering it to the virus surface . It’s the regular changes in the head of HA protein that keeps the virus ahead of our immune system and means that we have to update seasonal influenza vaccine most years. F16 binds to the more "constant" stalk, in parts highly conserved across subtypes, and so it stands a really good chance of protecting us against seasonal influenza. If it can’t, then it has at least identified portions of the HA stalk that could be used to create a universal vaccine or be targeted by anti-viral drugs.
If you are a subscriber to NEJM, you can read Russell’s article for a simple explanation of the significance of this discovery. If you are a really keen bunny, then I hope you read the original article by Corti et al in Science.
You may not have heard it here first, but 3rd hand is better than never when it comes to good news.
Stalking influenza diversity with a universal antibody C. R. Russell