Interstitium
the actual anatomical space or compartment within tissues where the interstitial fluid resides. This anatomical structure was previously thought to be a dense connective tissue layer, but in 2018, researchers identified and characterized the interstitium as a network of interconnected fluid-filled spaces between cells and the structural components of tissues, such as collagen and elastin fibers within the connective tissues of various organs, including the skin, lungs, digestive tract, and other tissues. The interstitium contains the interstitial fluid and serves as a supportive framework, allowing for flexibility and providing structural integrity.
