Interstitium: new organ discovered

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"The structure is a network of tissues which is found throughout the body, wrapping around the entire digestive tract,the lungs, and every artery and vein. The medical researchers dubbed the network the interstitium, and they argue should be deemed its own organ. [...] When researchers looked more closely, they saw that between the spread-out cells was a series of fluid-filled sacs. A series of strong but flexible tissue filled with functioning proteins connected all these sacs together. This, the researchers deemed wasn’t the same as other connective tissue found throughout the body and thus could be its own entity, which they dubbed the interstitium."