Differential gene expression analysis was carried out using the rank product method[16]. neuroactive ligand-receptor interactions are enriched among the most differentially regulated genes between adult human neural stem-like cells and adult human brain tissue. We confirmed the expression of 10 of the most up-regulated genes in adult human neural stem-like cells in an additional sample set that included adult human neural stem-like cells (n = 6), foetal human neural stem cells (n = 1) and human brain tissues (n = 12). The NGFR, SLITRK6 and KCNS3 receptors were further investigated by immunofluorescence and shown to be heterogeneously expressed in spheres. These receptors could potentially serve as new markers for the identification and characterisation of neural stem- and progenitor cells or as targets for manipulation of cellular fate. == Introduction == The discovery of adult neurogenesis and adult human neural stem-like cells (ahNSC) in the brain has opened a novel field of research aiming to utilise these cells as sources of repair in the treatment of degenerative disorders, such as Parkinson’s and Alzheimer’s disease[1]. ahNSCs can be isolated from the hippocampus or subventricular zone of the lateral ventricles (SVZ)[2][6]. Like stem cells from the rodent brain[7]they can be propagated and expandedin vitroas free floating neurospheres that are capable of self-renewal and can differentiate into all the three principal cell types of the central nervous system; neurons, oligodendrocytes, and astrocytes[6]. We have earlier shown that this includes neurons that generate action potentials[2],[3]and communicate by synapses[2]. Despite the great interest in and potential of ahNSCs, there is still limited knowledge regarding the hierarchy of stem- and progenitor cells in the human brain. This is in contrast to research around the hematopoietic cell lineage, where a detailed set of surface markers and transcription factors have been identified[8],[9]. Since the first successful attempt to phenotypically purify hematopoietic stem- and progenitor cells by simply depleting the lineage-restricted cells, the gradual discovery of new markers has made it possible to discriminate between long-term stem cells and more restricted progenitor populations. Comparable approaches have been used in attempts to identify markers that prospectively distinguish adult NSCs from neural Ginsenoside Rg2 progenitors in rodents. Most markers are however common to several stages[10]. Studies of NSCs from the adult human brain are still few and far between, although GFAP positive cells expressing the surface receptor NGFR was recently suggested as a markers of ahNSCs[11]. The exploration of the ahNSC lineage is undoubtedly challenged by our limited access to human brain tissues. To our knowledge, only two reports have directly explored the global transcriptome of adult human stem- and progenitor Ginsenoside Rg2 cells cultivated as free floating spheres. The cells explored in these studies were derived from the hippocampus and olfactory bulb and included only cells from one and two patients, respectively[12],[13]. Additional investigations of adult stem- and progenitor Flt4 cells Ginsenoside Rg2 from other parts of the human brain, not least the subventricular zone, is therefore necessary. Furthermore, selective markers that allow for a Ginsenoside Rg2 better separation of the different cell types cells in the lineage must be identified, and more efficient growth conditions to generate a sufficient number of cells both for research and patient treatment must be developed. We have recently compared ahNSCs to glioma stem cells (GSCs) and identified dysregulated pathways and putative targets for the treatment of glioblastoma[14]..