Contagious and full of viruses breath of sneezing or coughing person

(© Elena Abrazhevich -

BOSTON — How hard is it for people to fight off a virus? Scientists at Harvard University say it’s actually as easy as breathing, literally.

Their study reveals that the act of breathing generates immune responses that kill invading pathogens. In experiments, a “lung chip” that mimics the mechanical forces of breathing killed flu bugs. The discovery could lead to developing better medications for respiratory diseases, including COVID.

“This research demonstrates the importance of breathing motions for human lung function, including immune responses to infection, and shows that our Human Alveolus Chip can be used to model these responses in the deep portions of the lung, where infections are often more severe and lead to hospitalization and death,” says co-first author Dr. Haiqing Bai from Harvard’s Wyss Institute in a university release.

The alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and out.

“This model can also be used for preclinical drug testing to ensure that candidate drugs actually reduce infection and inflammation in functional human lung tissue,” Dr. Bai adds.

Breathing helps to exercise the lungs

The average person will take more than 600 million breaths over the course of their life. They stretch and relax the lungs with each inhale and exhale, respectively. Those motions influence their development and vital functions. The study, published in Nature Communications, now shows breathing’s role in combating infection.

Researchers also identified drugs that reduce the production of inflammatory proteins called cytokines — including one approved to treat COVID-19. Coronavirus inflections can generate a “cytokine storm” that can have deadly consequences, leading to organ failure.

Replicating immune defenses

The lung chip will provide new information on how lung tissues react to respiratory viruses that have pandemic potential and test potential treatments. Dr. Bai and colleagues lined the two parallel microfluidic channels with different types of living human cells. They included alveolar lung cells in the upper channel and lung blood vessel cells in the lower channel. This recreated the interface between human air sacs and their blood-transporting capillaries.

Researchers filled the channel lined by alveolar cells with air, while supplying the blood vessel channel with a flowing culture medium containing nutrients that are normally delivered by the blood. Scientists separated the channels using a porous membrane that allowed molecules to flow between them.

The team infected these “breathing” Alveolus Chips with H3N2 influenza by introducing the virus into the air channel. They observed the development of several known hallmarks of infection, including the breakdown of junctions between cells, a 25-percent increase in cell death, and the initiation of cellular repair programs.

Infection also led to much higher levels of multiple inflammatory cytokines in the blood vessel channel. In addition, the blood vessel cells of infected chips expressed higher levels of immune cells. The results confirmed that the Alveolus Chip could mount an immune response against H3N2 that replicate what happens in the lung of human patients infected with flu virus.

To their surprise, chips exposed to breathing motions ​​had 50 percent less viral mRNA in their alveolar channels and a significant reduction in inflammatory cytokine levels compared to static chips. Genetic analysis revealed the mechanical strain activated molecular pathways related to immune defense and multiple antiviral genes. These activations reversed when the cyclical stretching stopped.

These immunofluorescence micrographs (at different magnifications) show the 3D cellular structure that develops within the alveolar channel and mimics the microstructure of human alveoli. (Credit: Wyss Institute at Harvard University)

Stress alone can trigger an immune response

“This was our most unexpected finding – that mechanical stresses alone can generate an innate immune response in the lung,” says co-first author Professor Longlong Si, now at the Shenzhen Institute of Advanced Technology in China.

A higher strain caused an increase in innate immune response genes and processes, including several inflammatory cytokines.

“Because the higher strain level resulted in greater cytokine production, it might explain why patients with lung conditions like COPD suffer from chronic inflammation, and why patients who are put on high-volume ventilators sometimes experience ventilator-induced lung injury,” Prof. Si adds.

The team is exploring the incorporation of additional cell types such as macrophages into the chips to increase their complexity and model more biological processes, such as adaptive immunity. They are also using their existing model to study the efficacy of new compounds, drugs, and biologics against flu, COVID, and other diseases.

South West News Service writer Mark Waghorn contributed to this report.

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  1. Lash says:

    Coronavirus is not a respiratory disease. Try again.

    1. daveca says:

      Youre a Lying Troll Why?

      The Ncov 19 causes SARS 2 according to CDC. It causes the immune system to attack and destroy the lungs

      Not a question THAT youre a liar, buy WHY?

      Interesting how you LyingvTrolls blurt out ” no it isnt” but you never prove your Negative.

      Liars cant prove their statements, thats why theyre LIARS.

      1. DPJ says:

        Wow! Whether he/she is right or wrong, I bet you could use some duct tape around your head! I can only imagine how fast you typed that response…must have been burning the keyboard!!

      2. Jacob Worm says:

        LOL! The CDC is a dog and pony show meant to win your trust when in fact they are an adversary. Nothing is as it seems.

    2. Teresa says:

      Hi 🙂 Our whole family (husband myself and our two kids) all caught Covid at the same time.. Our Dr told us its a pulmonary virus, meaning it can attack and invade anywhere in your body..lungs..etc. It got into all of our bronchi, and it attacked my gallbladder of all things!.. which we found out the Drs were seeing a pattern of gallbladder inflammation, with no history of gallbladder disease, in mostly my symptoms were consistent with this finding. We also learnt that Covid will seek out a person’s weakest or previously injured all four of us had pain and inflammation in areas we’d hurt before..backs, legs, ankles, etc.. Hope this helps! 🙂 Its a tricky little bugger, this covid.. If anyone in this chat have had it, hope you dully recover and quickly at that <3

    3. Jacob Worm says:

      You’re right but do you know why and how they are getting away with these lies? And those that look to the CDC or any other so-called “experts” better do the homework for themselves. The lies that we have been weaned on are so great that if you don’t learn the truth for yourself, you will never believe anyone else. Very few know the truth. Very few.

  2. daveca says:

    1. Breathe deeply.
    2. Eat right”, drink milk- Vit D

    So, just healthy practice and eating right.

    No poison vaccines that last a few weeks!

    1. DPJ says:

      Agree. Live your life normally. Take a multi-vit, C, D, etc. Walk every day. Be happy; don’t watch the news.

      1. David P L says:

        Every person with a serious case of covad was breathing when they caught it. I’m sure the respiratory system and the immune system fights against disease such as covad, but it is much better at it with vaccinations. I’m not satisfied with a 95% chance. Give me the 99.999 % chance.

    2. Chris says:

      Only 97 times more likely to die without the vaccine than with it. Red states had a 38% higher death rater per capita after the vaccine became available. But who needs science when you have belief.

  3. Kevin M says:

    It’s when they stop breathing that there’s a problem.

  4. Flurf says:

    The headline translates into: Humans can survive viruses by staying alive.
    This is the best/worst headline I have read recently.

  5. Vox Veritatis says:

    “Humans can fight off viruses simply by breathing”

    “They are also using their existing model to study the efficacy of new compounds, drugs, and biologics against flu, COVID, and other diseases.”

    Don’t hold your breath.

    1. Jacob Worm says:

      And don’t suffocate yourself with a mask and breath back in all the toxins you were designed to breath out. The medical industry is not your advocate.

  6. Jim Robinson says:

    I read it, and still don’t get it, who doesn’t breath?

  7. Leethal says:

    Deep nose breathing also lowers blood pressure and anxiety. Practice calming deep breathing daily.

  8. WhatIf says:

    It would be a helluva a lot easier to defeat the Chinese bio-weapon if Heir Biden and his Reich Ministers wouldn’t force us to wear masks that doesn’t stop the bio-weapon but does restrict us from breathing normally.

  9. 1stAmendment says:

    what ever happened to freedom of speech not censored by unseen dark forces?

  10. Jim Queen says:

    So let’s slap a mask on and inhibit breathing.

  11. fb0252 says:

    would breathing in isopropyl alcohol or breathing in heat kill virus?

    1. Jacob Worm says:

      Sunshine kills pathogens that get exhaled in the air. The medical industrial complex has lied to you about everything. The doctors have cognitive dissonance as well.

  12. Tom says:

    You can survive even better by smoking weed. Google it. It not only works as a therapeutic, but it also inhibits infection in the first place. It also has the additional effect of making you not care if you have it or not.

  13. Tom says:

    So…if you stop breathing, you’ll die from the virus?

  14. Tom says:

    So if you stop breathing, the virus will kill you?

  15. Clifton Thomas Moberg says:

    if something growing in the lungs is anaerobic as in [relating to, involving, or requiring an absence of free oxygen: “anaerobic bacteria”] then it stands to reason that very deep breathing–even to lifting the shoulders high–will counter this growth rate.

  16. Frank says:

    Breathing is for suckers.

  17. Hector says:

    So, Based on this article, CPAP users might fair better than those who don’t?

  18. MHart says:

    Ever notice StudyFinds publishes every report that says the word “study” whether it’s legit or not? I notice every time. It’s a website for BS.

  19. Bill Hanks says:

    I have been doing the Wim Hoff method for two years. I am 73 and been around a lot of Covid patients. I feel that his method has really helped me the past two years. You check him out on Youtube.