Interstitium, Apoplast.

I learned a couple of new words from this fascinating “interactive” NY Times article by Abraham Z. Cooper, a pulmonary and critical care physician and associate professor of medicine (archived versions don’t seem to work, because of the interactivity, but hopefully you can read the text at Facebook): In 2021, researchers described what they saw when they had examined skin-biopsy samples that included tattoos: The ink particles had traveled deeper than anticipated, through interstitial spaces into the tissue underneath the skin, or the fascia. “That wasn’t supposed to happen,” Neil Theise, a professor of pathology at New York University and a senior author of the paper reporting the results, told me. The existence of an apparent conduit between skin and the fascia beneath it — two tissue layers not known to connect with each other in this way — broke accepted anatomic boundaries. The researchers also found that the same was true for other previously unknown microscopic connections…