Nestin is an intermediate filament protein involved in regulating filament assembly, cell remodeling, regeneration, and neural development during embryogenesis. It is a marker of cell migration and proliferation and of progenitor neural cells. Nestin is mostly expressed in cells during development and expression is lost in terminally differentiated cells. It is also expressed in regenerating tissues and as part of the stress response to injury. It stains positively in progenitor neuroepithelial stem cells in the central nervous system (CNS) and in precursor cells of the peripheral nervous system (PNS), and in a subset of adult neurons in the basal forebrain. Nestin also sees expression outside of the CNS and PNS, generally in cells that are pluripotent or undifferentiated, highly mobile, or responding to injury or disease. It may show positivity in endothelial cells, myoepithelial cells, renal glomeruli, cardiac myocytes, the retina, striated muscle, the pancreas, the liver, kidneys, skin, teeth, testes, and the adrenal gland. In cancer, it is expressed in various tumors of the central nervous system, including astrocytic gliomas, neurocytomas, neuroblastomas, ependymomas, medulloblastomas and Schwannomas. References: Journal of Clinical Pathology 2005;58:222-223; PLoS ONE. 2010 Dec. 6(4): e18535, DOI:10.1371/journal.pone.0018535; J Interdiscipl Histopathol. 2016. 4, DOI: 10.5455/jihp.20160420021353; Histol Histopathol. 2005 Apr;20(2):665-71; Neuroscience and Behavioral Physiology. 2008 Feb. 38(2):165–169, DOI: 10.1007/s11055-008-0025-z;