The Neuroendocrine Leydig Cells and their Stem Cell Progenitors, the Pericytes

cells, and the testicular localization of the intermediate filament protein nestin, known to be expressed in neural stem cells, by our group was the first step to define mural cells (pericytes and vascular smooth muscle cells) of the testis microvascu- ture as the stem/progenitor cells of the adult Leydig cells.