ABSTRACT
The endothelium is recognized as a specialized epithelium lining the vasculature, the lymphatic vessels and the heart (Dyer and Patterson 2010). German anthropologist and pathologist Rudolph Virchow is credited with the earliest known description of this tissue in the mid 19th century, and the term endothelium (from the Greek end meaning within, and thele meaning nipple) was coined by the Swiss anatomist Wilhelm His soon after (to distinguish it from epithelium, i.e., outside the nipple). Despite its century and half-long medical history, the complexity of the endothelium has only relatively recently come to light. Indeed, Virchow’s banal characterization of the capillary lining as “a membrane as simple as any that is ever met with in the body” (Laubicher et al. 2007), and Lord Florey’s no less fl attering account-nearly a century later-of the endothelium as “a sheet of nucleated cellophane” (Florey 1966), initially branded the endothelium as phenotypically invariant and serving only a passive barrier function. This interpretation has since changed considerably.
