Fighting the flu: boosting the immune system in the elderly
26 November 2014
It’s late November. It’s starting to get pretty chilly; you’re debating whether it’s OK to put the heating on yet; and then you start to get just a hint of a sore throat. Which develops into a cough. And a runny nose. And before you know it, you’re laid up with a full-blown cold. It’s well known that the elderly are more susceptible to common illnesses like the flu than younger people, but it’s less well understood why. However, recent research by Katja Simon’s lab in the Human Immunology Unit at the WIMM has not only identified a key process involved in flu susceptibility in the elderly, but also a drug which might help to alleviate the problem. Dr. Bryony Graham explains more.
Your body is pretty good at recognizing what belongs to it, and what doesn’t. If it sees something floating around in your blood that most certainly should not be there, it mounts a full attack against it and swiftly removes the offending item from your system. Whilst this process is going on, you might possibly feel a little poorly, but in the long run you come out the other side relatively unscathed.
What’s pretty clever is that your body then remembers that nasty little bug that caused you to be ill in the first place, so that if aforementioned bug manages to sneak its way in again, your body is armed and ready to fight it off without you even noticing.
That’s what happens during immunisations: you are given a low dose or an inactive version of the bug or virus in question so that your body THINKS it has had an infection, but all you really get is the benefit of the memory of it, and therefore the ability to fight off that infection quickly in the future.
However, the ability of your body to remember infections that you’ve had in the past is impaired with age. Nobody has really understood why this is though – until now.
This month, scientists working in Katja Simon’s lab in the Human Immunology Unit at the WIMM found that a process called autophagy is essential for the ability of the immune system to remember an infection.
Autophagy is the process that clears up all the rubbish and waste that is produced inside a cell as it goes about its daily business, and as mammals age, this process becomes less effective. The Simon lab found that if they gave the cells a drug that restored the process of autophagy to normal, then the cells responded normally to a flu vaccine again.
Scientists working in the Simon lab are now trying to understand exactly how this drug works, in order to establish whether it could potentially be used in humans as an immune-system boosting agent. Although it could be up to 10 years before the new drug reaches the clinic, these findings represent a significant step towards helping the aged population fight off common infections to which they are currently so worryingly vulnerable.
Post edited by Katja Simon and Dan Puleston.