A new human “organ” has been recognized, according to scientists who describe the interstitium as a layer of fluid-filled compartments under the skin throughout the body that act as shock absorber.
Doctors and scientist initially considered the widespread, fluid-filled spaces to be tissue, but a study published in the journal Scientific Reports on Tuesday has suggested the interstitium is an organ.
Dr. Neil Theise, a co-senior author of the study and a professor of pathology at NYU Langone Health in New York City, explained that an organ’s definition is determined by two ideas: either that it features a unitary structure or that it is a tissue featuring a unitary structure.
“This has both,” he said of the interstitium, per CNN. “This structure is the same wherever you look at it, and so are the functions that we're starting to elucidate.”
The discovery could help scientists understand how cancer spreads.
“We’ve defined novel microanatomy and have laid the groundwork for how this may begin to explain cancer spread, inflammation and scarring of connective tissue,” said Dr. Petros Constantinos Benias, co-lead author of the study and a member of the Feinstein Institute and assistant professor at Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Health.
“This discovery will open up new research pathways for inflammation and cancer progression,”
To give a clearer picture of what the interstitium is, the Feinstein Institute described it as “a series of spaces, supported by a meshwork of strong and flexible connective tissue proteins found below the skin’s surface, lining the digestive tract, lungs and urinary systems, and surrounding arteries, veins, and the fascia between muscles.”
Until now, the skin was considered the largest organ, making up roughly 16 percent of the body’s mass, but researchers estimate that the interstitium could make up around 20 percent of the body’s volume, CNN noted.
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