Cordocyte | biography

Cordocytes (from the Greek words chorde meaning "cordon" and kytos meaning "cell"), initially named interstitial cells of Cajal-like cells (ICC-LCs), are cells with a small body and extremely long prolongations, located in many anatomical regions in the brain, such as pia mater, subarachnoid space, reticular arachnoid, cerebral ectocortex, white matter, choroid plexus, and copiously found around large vessels, arteries and veins throughout the human brain.

Despite their small body, these cells can be seen using a light microscope, except their very thin processes observed under greater resolving power. Using a conventional transmission electron microscope, all these thin processes can be visualized. However, different subpopulations exist morphologically depending on their differentiation grade and microenvironments. Ultrastructurally, these special interstitial cells are characterized by an ovoid nucleus with a small but prominent nucleolus and a specific arrangement of heterochromatin. In their electron-dense cytoplasm, numerous large mitochondria, polyribosomes, rough endoplasmic reticulum, Golgi apparatus, lysosomes, filaments, caveoles, multivesicular bodies, glycogen, etc. can be seen; occasionally, a discontinuous basal lamina and exosomes are observed in the proximity of their filopodia along with thin, long prolongations, often ramified dichotomically.

Morphofunctionally, these cells have unique properties, great capacity of autonomy, plasticity and interconnections, rapidly changing their phenotypes, position and number, as genuine supervisors in their locations and interactions. These cells should be better and rapidly investigated from genesis to death, for their multifunctional neuroprotective and vasculoprotective roles in the brain.

Leptomeningeal cordocytes, either pial cells or some arachnoid cells as well as perivascular cordocytes, arterial cordocytes or venous cordocytes are multifunctional cells and active local supervisors, from their genesis to death. In addition, these cells are promptly migrating to injured areas, their processes growing very fast, their cell membranes performing a variety of functional contacts under various requirements and spatial possibilities. Therefore, these cells appear to form a regulatory interface between other cells and/or structural complexes, surrounding them specifically, and therefore being named "cordocytes."

This special interstitial cell was described for the first time in the human brain in 2005 and named cordocyte in 2011 by the Romanian scientist Viorel Pais. The name is proposed because the encirclement of their targets is a general rule in the most protective responses, either inhibiting by asphyxiation the proliferation and dissemination of transformed cells on their malignant pathway or protecting normal structures adopting a monolayer or multilayer position. Under their strict surveillance all cellular movements are controlled, and under their efficient protection all vessels are surrounded by these cells acting primarily against erythrocyte extravasation. This is an important finding because the brain performance depends on the appropriate pericortical conditions. Cordocytes have a fundamental role in cooperation with stem cells for producing new cells during regeneration and repair events throughout the brain. Also, these special interstitial cells coordinate and direct stem cells to damaged areas. Thus, cordocytes in association with stem cells could be good candidates for transplantation and repair of the nervous system in this new neurorestoratology era. It was recently demonstrated the presence of cordocytes in the human skin. Revolutionary ideas emerging from the discovery of cordocytes will change the classical concepts concerning the nature and function of the pia mater, while the knowledge horizon regarding clinical applications of cordocytes-stem cells cooperation becomes more and more a reality.