This scanning electron micrograph shows epithelial cells lining the inside of the lung.
In a recent study, researchers from the Francis Crick Institute in the UK were surprised to discover that these cells, rather than immune cells, are responsible for early flu resistance induced by microbiota.
“They are the only place that the virus can multiply, so they are the key battleground in the fight against flu,” says research leader Andreas Wack. “Gut bacteria send a signal that keeps the cells lining the lung prepared, preventing the virus from multiplying so quickly.”
However, this can be compromised when antibiotics are taken.
When mice with healthy gut bacteria were infected with the flu, around 80% survived. However, only a third survived if they were given antibiotics before being infected.
“We found that antibiotics can wipe out early flu resistance, adding further evidence that they should not be taken or prescribed lightly,” says Wack.
“Inappropriate use not only promotes antibiotic resistance and kills helpful gut bacteria, but may also leave us more vulnerable to viruses. This could be relevant not only in humans but also livestock animals, as many farms around the world use antibiotics prophylactically.
The findings are published in the journal Cell Reports.