Cardiac Telocytes

Telocytes (TCs) are interstitial cells previously characterized by electron microscopy as cells with very long extensions (telopodes, Tps), present in numerous organs, including the heart interstitial space and cardiac stem cell niche. TCs have several particular morphological and phenotypical properties, as well as specific gene expression and proteomic profiles which define TCs as a distinct type of interstitial cells, different from fibroblasts. Given the fact that TCs interact through Tps with identical cells generating a network, as well as with other type of cells, including vascular and nervous cells, it has been proposed that TCs have a role in the fine-tuning of regulatory signals delivered through vascular, nervous and endocrine systems. TCs have been found within the stem cell niche of several organs. TCs release extracellular vesicles (EVs) in vivo and in vitro, suggesting that they may regulate the activity of other cells, including cardiac stem cells (CSCs), by vesicular paracrine signals. The most advanced morphological studies using focused ion beam scanning electron microscopy (FIB-SEM tomography) showed the 3D reconstruction of cardiac TCs.