Scientists discover how lungs are damaged during the flu

Ever wondered why you get painful coughs during the flu? Scientists have now discovered what happens inside our lungs.

Influenza damages our lungs by activating a ‘self-destruct button’ within them, a Melbourne laboratory has found, shedding light on a decades-old mystery.

The discovery could one day pave the way for a universal influenza treatment, which would be a major advancement given our reliance on strain-specific flu vaccines.

The flu virus can cause significant damage to our lungs, but the ‘how’ has been a mystery until now.

The new research, from Melbourne’s Hudson Institute, shows the influenza virus harms our respiratory system by essentially turning our body against us, and activating a protein naturally found in the lungs.

Associate Professor Michelle Tate said the activated protein causes the main cell in our lungs, called epithelial cells, to explode.

“Gasdermin E acts like a ‘self-destruct button in lung epithelial cells during infection, causing them to burst and release inflammatory signals,” she said.

When we get the flu a protein naturally found in our lungs is activated and it then causes the main cells to explode.

“[It] plays a major role in causing lung damage during influenza.”

She said, up until now, the assumption had been that it was the virus itself that caused the explosion — and subsequent damage — but they now know it’s actually “the host”.

“So what we’ve known for a very, very long time — because influenza has been studied for over 100 years — is that when it goes into the main cell in your lung … it causes them to die and explode,” she said.

“But we haven’t really understood why.”

Prof Tate said they began looking into Gasdermin E because they’ve been studied heavily in cancer — but never influenza — and were “known to cause cell death”.

“It’s always there, but it’s not in activated form,” she said.

“So what happens is the virus comes in, it gets activated and then it causes holes in the surface of a cell.

“Eventually, all this water comes into the cell, it swells up and then eventually it explodes.”

She said, by understanding how influenza causes damage, they could develop better treatments, such as a therapy that blocks the protein.

“Every year, thousands of people, especially adults 65+ and those with weakened immune system, get seriously ill from the flu,” she said.

“When we removed this protein, the lungs stayed healthier, and the flu was less severe.

“Our findings could lead to new medicines that reduce lung damage and inflammation, helping people recover faster and lowering the risk of death from severe flu.”

The discovery could pave the way for new medicines. Picture: iStock

She said they were confident their findings, originally demonstrated in mouse experiments, translated to humans as they tested human cells for the second part of their experiment.

She said their research was also exciting because multiple, different influenza strains activated the protein, offering a common thread for therapies to target.

“At the moment, a vaccine is very strain specific,” she said.

“If we were able to make a drug, it would likely be effective with any strain of virus.”

The research was published in Cell Death and Disease.