The pericyte progenitors and the pericytes are the ancestors of the inner ear structures

Abstract

This short scientific overview concerns the morpho-functional comparison between the omnipresent pericytes and the pericytes of the inner ear and, besides some characteristic features of the last, provides evidence that the otic pericytes are authentic part of the omnipresent pericyte (adult stem cell) population of the vertebrate organism. In the present review we offer evidences for a new hypothesis that the pericyte progenitors and the pericytes, as pluripotent epiblast derivatives, are the ancestors of the supporting and hair cells of the Corti organ, the cells of the vestibular (balance) organ and the neural elements of the inner ear in norm and experiment. The most important evidences for this statement provide results concerning: 1. the origin of the inner ear vasculature; 2. the close relationships of the pericytes with the microvasculature of the inner ear (periendothelial location in microvascular niches); 3.their importance for the blood-labyrinth barrier; 4. the events that accompany the origin of the inner ear sensory epithelia; 5. the authentic stem cell qualities of the pericytes allowing the production of cells and tissues characteristic for the three embryonal germ layers: ectoderm, mesoderm and endoderm (during embryogenesis, in the adult organisms and at experimental and pathological conditions), as well as 6. the remarkable pericyte plasticity and their involvement in the immune system.