Email Print Share

"Protective Seal" -- The Discovery Files

The Discovery Files
Audio Play Audio
The Discovery Files podcast is available through iTunes or you can add the RSS feed to your podcast receiver. You can also access the series via AudioNow® by calling 641-552-8180 on any telephone.

Scientists have discovered that seal blood has the ability to minimize the effects of an inflammatory response during dangerous deep-sea dives. The inflammatory effects of a bacterial toxin -- lipopolysaccharide -- are 50 to 500 times greater in humans than seals, and tests on mice immune cells suggest that the special properties of seal blood could protect the lungs of human deep divers.

Credit: NSF/Karson Productions

Audio Transcript:

Going deep.

I'm Bob Karson with the Discovery Files, from the National Science Foundation.

A team of researchers led by Massachusetts General Hospital is on a different kind of seal hunt: (Sound effect: seal sound) one to uncover why seals -- a mammal -- can take a deep-sea dive and resurface with their lungs no worse for wear.

On the way down, a seal's delicate lung tissues get injured as they're crushed, then suffer blood and oxygen flooding when the seal heads back up. Not bad enough? The fragile tissues could suffer inflammation, usually a response by the body to heal damage. Yet the researchers found no evidence of lung damage in these deep divers.

How do seals protect their lungs from the potentially damaging inflammatory response? The scientists think they've uncovered the "secret sauce." They tested whether blood samples from two seal species offered any protection from the effects of inflammation triggered by a bacterial toxin. Result: The toxin triggered barely any inflammatory response in the seal blood. Do the same test in humans, and inflammation is 50 to 500 times greater!

And when the team added serum from seal blood to mouse immune cells, there was no inflammatory response.

The study suggests seal serum's protective compounds could help deep sea divers and offer promise in extending the survival of organs used in transplants.

Guess you could say we're learning a seal's deepest secrets. (Sound effect: seal sounds)

"The discovery files" covers projects funded by the government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at or on our podcast.

General Restrictions:
Images and other media in the National Science Foundation Multimedia Gallery are available for use in print and electronic material by NSF employees, members of the media, university staff, teachers and the general public. All media in the gallery are intended for personal, educational and nonprofit/non-commercial use only.

Images credited to the National Science Foundation, a federal agency, are in the public domain. The images were created by employees of the United States Government as part of their official duties or prepared by contractors as "works for hire" for NSF. You may freely use NSF-credited images and, at your discretion, credit NSF with a "Courtesy: National Science Foundation" notation. Additional information about general usage can be found in Conditions.

Also Available:
Download the high-resolution JPG version of the image. (66.6 KB)

Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer.

MP3 icon
NSF podcasts are in mp3 format for easy download to desktop and laptops, as well as mobile devices capable of playing them.