Nestin, an important marker for differentiating oligodendroglioma from astrocytic tumors

Nestin is an intermediate filament (IF) protein. These intermediate filament proteins are expressed mostly in neural stem cells [1-3]. Nestin is also expressed by many other stem cells and it is considered a primitive marker [4-7] . Upon differentiation, Nestin becomes down-regulated and is replaced by tissue-specific intermediate filament proteins [8]. During neuroand gliogenesis, Nestin is replaced by cell type-specific intermediate filaments, e.g. neurofilaments and glial fibrillary acidic protein (GFAP) [9]. One instance of Nestin expression in adult organisms, and perhaps that for which Nestin is best known, are the neuronal precursor cells of the subventricular zone [8,10]. Interestingly, Nestin expression is reinduced in the adult during pathological situations, such as the formation of the glial scar after CNS injury and during regeneration of injured muscle tissue [11]. Nestin expression has been extensively used as a marker for central nervous system (CNS) progenitor cells in different contexts [4]. Nestin has recently received attention as a marker for detecting newly formed endothelial cells [3,12].