rationalskepticism.org

Newly identified networks of interconnected, fluid-filled chambers that line tissues throughout the human body may qualify as a completely new organ, researchers report in a study published Tuesday in Scientific Reports.

Researchers found the web-like tissue on the underside of skin, around the digestive tract, bladder, lungs, arteries, and within muscles. They speculate that the tissues—dubbed the “interstitium”—may act as “shock absorbers,” allowing our organs to swell and compress as we go about our business of breathing, eating, and living in general. The fluid it contains may also play heretofore unappreciated roles in basic biology and disease. For instance, the liquid could act as a conduit for cellular signals or harmful molecules, play a role in the development of edema (excessive fluid retention in tissues), and even help cancer cells spread.