Roles and distribution of telocytes in tissue organization in health and disease

Telocytes (TCs) are interstitial cells that distinguish themselves through their particular architecture, consisting of a relatively small cell body that emits remarkably long and narrow prolongations called telopodes (Tps). Previously known as interstitial Cajal-like cells, TCs manage to develop complex networks in almost all organs of the human body. Although staining positively for vimentin antibody, some uncertainty still persists over the mesenchymal origin of these cells. The election method for the precise detection of biological structures is focused ion beam scanning electron microscopy, which ensures an accurate visualization of cellular architecture by providing sharper images of three-dimensional bodies, reaching nanoscale resolution. This approach has thus become the gold-standard for the identification of TCs. With the aid of currently available technology, TCs have been demonstrated to cover a wide range of functions that stretches from their role in electrical conduction and contractility adjustment to the coordination of tissue regeneration and angiogenesis. Because of their ability to form homo- and/or heterojunctions, TCs successfully provide resistant mechanical support. They exert their roles by ensuring intercellular signaling, either through direct cell–cell interaction or through juxtacrine and/or paracrine interactions aided by shedding bodies and exosomes delivered by Tps. The complex networks regulated by TCs have recently been proposed to form barriers between parenchymal compartments. This theory is supported by the abundant collagen fibrils that surround the Tps, thus strengthening their pivotal role in the establishment of tissue architecture. The numerous demonstrated and potential roles of TCs without a doubt require further investigation, especially because of their promising functions in regenerative medicine.