The human body houses a continuous network of fluid-filled compartments between cells that spans organs and is perhaps involved in disease spread, according to research published on March 31 in Communications Biology.
In 2018, the same research team demonstrated the existence of these fluid-filled spaces, which they dubbed the interstitium, challenging conventional wisdom that the space between cells is dense connective tissue. The use of fixed tissues under microscopes had inspired this error, as the fixation process drains the samples of fluids.
While that first paper was provocative—some anatomists pushed back against the authors framing their discovery as a new organ—it did not settle the question of whether the interstitium remains within the cells of discrete organs or crosses between different organs. The authors now say the latter is true, and that the interstitium could act as a conduit for cancers and other diseases to travel throughout the body, in ...