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SCIENSPOT is a podcast that shines spotlights on the latest scientific technology from Japan.
Your host is REN from SCIENTALK.
ウイルス感染のメカニズム
Today, I want to talk about viral infections.
Viral infections usually start in just a small number of cells in your body,
but then they quickly spread to a wider area, affecting your whole system.
However, the specific mechanism of how this infection spreads from a few cells to a wider spread to areas has not been well understood until now.
It's like, imagine a burglar breaking into just one house.
How does that quickly spread to the neighbors and the days throughout the entire town?
That transmission route has been a mystery.
Previous research had already shown that when the concentration of a substance called calcium ions inside cells increases,
influenza viruses become more likely to infect those cells.
Calcium ions are really important components involved in various life activities within cells.
So there was already a known connection between calcium ions and viral infections.
This time, a research group from Hokkaido University, Osaka University, and Kyushu University has made an astonishing discovery that unravels this mystery.
This found that cells infected with a virus actually send a special message molecule called ADP,
adenosine diphosphate, to surrounding uninfected cells.
ADP is a molecule typically involved in energy transfer within cells.
Imagine an infected house sending out a danger message to the safe houses around it.
When surrounding cells receive this ADP message through an ADP receptor,
which acts like an antenna, the concentration of calcium ions inside those cells significantly increases.
カルシウム波の伝播
And it was found that this increase in calcium ions concentration spreads like a ripple effect, moving sequentially to adjacent cells.
The research group named this phenomenon calcium wave propagation.
It's exactly like a game of telephone where the message is passed along one by one.
What's truly, the influenza virus has skillfully hijacked this chatter between cells, this calcium wave propagation mechanism.
The virus utilizes this ADP-mediated communication to make uninfected cells more susceptible to infection, thereby accelerating its spread.
It's almost as if the burglar took over the neighborhood's emergency communication network to make it easier to break into house after house.
To uncover this phenomenon, the research group used a super wide-field, high-resolution microscope named Amateras.
This is an incredibly powerful microscope that can observe hundreds of thousands to a million cells simultaneously,
allowing them to capture the dynamics of calcium ions across the entire cell populations.
And they clearly observed with Amateras how a wave of increased calcium ions concentration propagated from the virus-infected cells to the surrounding cells.
Furthermore, as crucial evidence for this research, the group conducted experiments using a drug that blocks ADP receptors.
When ADP receptors were disrupted by this drug, the calcium wave propagation stopped, and viral infection was effectively suppressed.
What's more, this result was confirmed not only at the cellular level but also in experiments using mice.
This strongly suggests that calcium wave propagation plays an extremely important role in the spread of viral infection, even within living organisms.
This discovery is a significant step towards solving the long-standing mystery of how influenza viruses spread infection within the body.
ウイルスと細胞間コミュニケーション
Viruses cunningly exploit cell-to-cell communication to accelerate their infection.
This new therapeutic approach, which targets cell-to-cell conversation, differs from drugs that target the virus itself.
It offers the potential to reduce the risk of viruses developing drug resistance, and there are high hopes for future development of new antiviral drugs based on this finding.
That's all for today's SciencePod.
This podcast is broadcasted daily on weekday morning in both Japanese and English.
I'd love for you to listen to the podcast and post your notes with the hashtag SciencePod.
Thank you for listening and see you next time.
