Project description:Adult neural progenitor cells (aNPCs) are a potential autologous cell source for cell replacement in neurologic diseases such as Parkinsonâs disease or stroke or for cell-based gene therapy for neurometabolic diseases. Easy accessibility, long-term expandability and detailed characterization of NPC properties are important requisites for their future translational/clinical applications. aNPC can be isolated from different regions of the adult human brain including the accessible subcortical white matter (aNPCWM), but systematic studies comparing long-term expanded aNPCWM with aNPC from neurogenic brain regions to check for their NPC characteristics and performance are not available. Freshly isolated cells from subcortical white matter and hippocampus (aNPCHIP) expressed oligodendrocyte progenitor cell (OPC) markers such as A2B5, NG2 and OLIG2 in ~20% of cells but no neural stem cell (NSC) markers such CD133 (Prominin1), NESTIN, SOX2 or PAX6. The EGF receptor (EGFR) protein was expressed in 18% of aNPCWM and 7% of aNPCHIP, but only a small fraction of 1 cell out 694 cells from white matter and only 1 out of 1,331 hippocampal cells were able to generate neurospheres. Studies comparing subcortical aNPCWM with their hippocampal counterparts showed that both NPC types expressed mainly markers of glial origin such as NG2, A2B5 and OLIG2, and the NSC/NPC marker Nestin, but no pericyte markers. Both NPC types were able to produce fully mature neurons, astrocytes and oligodendrocytes in comparable amounts to fetal NSC. Whole transcriptome analyses finally confirmed the strong similarity of aNPCWM with aNPCHIP. Our data show that aNPCWM are multipotent NPC with long-term expandability capacity similar to NPC from hippocampus making them an easily accessible source for possible autologous NPC-based treatment strategies. Isolation and propagation of multipotent NPCs. Adult human hippocampal (hip) and subcortical white matter (wm) tissue was obtained from routine epilepsy surgery procedures following informed consent of the subjects. All procedures were in accordance with the Helsinki convention and approved by the Ethical Committee of the University of Dresden (No. 47032006). All subjects underwent high-resolution magnetic resonance imaging excluding tumors and were screened for the presence of infectious disease. In all cases the neuropathological examinations did not reveal evidences for tumor formation. Gene expression Single-channel oligonucleotide microarray analysis. For the gene expression microarray analysis we used the Affimetrix U133A chips containing 22.215 probe sets representing at least 12.905 individual genes. The whole procedure was performed following the manufacturerâs standard protocol (Affimetrix, Santa Clara, CA). For the data processing, normalization was calculated with the GCRMA (GC content corrected Robust Multi-array Analysis) algorithm. fNSC: Human fetal neural stem cells, 2 biological rep aNPChip: Human adult neural progenitor cells isolated from hippocampus, 3 biological rep aNPCwm: Human adult neural progenitor cells isolated from white matter, 2 biological rep
Project description:Adult neural progenitor cells (aNPCs) are a potential autologous cell source for cell replacement in neurologic diseases such as Parkinson’s disease or stroke or for cell-based gene therapy for neurometabolic diseases. Easy accessibility, long-term expandability and detailed characterization of NPC properties are important requisites for their future translational/clinical applications. aNPC can be isolated from different regions of the adult human brain including the accessible subcortical white matter (aNPCWM), but systematic studies comparing long-term expanded aNPCWM with aNPC from neurogenic brain regions to check for their NPC characteristics and performance are not available. Freshly isolated cells from subcortical white matter and hippocampus (aNPCHIP) expressed oligodendrocyte progenitor cell (OPC) markers such as A2B5, NG2 and OLIG2 in ~20% of cells but no neural stem cell (NSC) markers such CD133 (Prominin1), NESTIN, SOX2 or PAX6. The EGF receptor (EGFR) protein was expressed in 18% of aNPCWM and 7% of aNPCHIP, but only a small fraction of 1 cell out 694 cells from white matter and only 1 out of 1,331 hippocampal cells were able to generate neurospheres. Studies comparing subcortical aNPCWM with their hippocampal counterparts showed that both NPC types expressed mainly markers of glial origin such as NG2, A2B5 and OLIG2, and the NSC/NPC marker Nestin, but no pericyte markers. Both NPC types were able to produce fully mature neurons, astrocytes and oligodendrocytes in comparable amounts to fetal NSC. Whole transcriptome analyses finally confirmed the strong similarity of aNPCWM with aNPCHIP. Our data show that aNPCWM are multipotent NPC with long-term expandability capacity similar to NPC from hippocampus making them an easily accessible source for possible autologous NPC-based treatment strategies. Isolation and propagation of multipotent NPCs. Adult human hippocampal (hip) and subcortical white matter (wm) tissue was obtained from routine epilepsy surgery procedures following informed consent of the subjects. All procedures were in accordance with the Helsinki convention and approved by the Ethical Committee of the University of Dresden (No. 47032006). All subjects underwent high-resolution magnetic resonance imaging excluding tumors and were screened for the presence of infectious disease. In all cases the neuropathological examinations did not reveal evidences for tumor formation. Gene expression Single-channel oligonucleotide microarray analysis. For the gene expression microarray analysis we used the Affimetrix U133A chips containing 22.215 probe sets representing at least 12.905 individual genes. The whole procedure was performed following the manufacturer’s standard protocol (Affimetrix, Santa Clara, CA). For the data processing, normalization was calculated with the GCRMA (GC content corrected Robust Multi-array Analysis) algorithm.
Project description:Glial progenitor cells (GPCs) of the adult human white matter, which express gangliosides recognized by monoclonal antibody A2B5, are a potential source of glial tumors of the brain. We used A2B5-based sorting to extract progenitor-like cells from a range of human glial tumors, that included low-grade glioma, oligodendroglioma, oligo-astrocytomas, anaplastic astrocytoma, and glioblastoma multiforme. The A2B5+ tumor cells proved tumorigenic upon orthotopic xenograft, and the tumors generated reflected the phenotypes of those from which they derived. Expression profiling revealed that A2B5+ tumor progenitors expressed a cohort of genes by which they could be distinguished from A2B5+ GPCs isolated from normal adult white matter. Most of the genes differentially expressed by glioma-derived A2B5+ cells varied as a function of tumor stage; however, a small number were invariably expressed at all stages of gliomagenesis. These glioma progenitor-associated genes included CD24, SIX1 and EYA1, which were up-regulated at all stages of gliomagenesis, and MTUS1 and SPOCK3, which were down-regulated at all stages of tumor progression. qPCR and immunolabeling confirmed the differential expression of these genes in primary gliomas, while pathway analysis permitted their segregation into differentially active signaling pathways. By comparing the expression patterns of glial tumor progenitors to their identically-isolated normal homologues, we have identified a discrete set of oncogenic pathways by which glial tumorigenesis may be both better understood, and more efficiently targeted. Samples originating from patients with matched disease and/or pathology were considered as replicates either on the basis of exact tumor phenotype, tumor grade, or tumor vs. normal tissue samples.
Project description:OBJECTIVE: Glial progenitor cells are abundant in adult human white matter. This study was designed to identify signaling pathways regulating their self-renewal and fate. METHODS: We compared the transcriptional profiles of freshly sorted adult human white matter progenitor cells (WMPCs), purified by A2B5-based immunomagnetic sorting, with those of the white matter from which they derived. RESULTS: We identified 132 genes differentially expressed by WMPCs; these included principal components of five receptor-defined signaling pathways, represented by platelet derived growth factor receptor alpha (PDGFRA) and type 3 fibroblast growth factor receptor (FGFR3), receptor tyrosine phosphatase-beta/zeta (RTPZ), notch, and syndecan3. WMPCs also differentially expressed the bone morphogenetic protein 4 (BMP4) inhibitors neuralin and BAMBI (BMP and activin membrane-bound inhibitor), suggesting tonic defense against BMP signaling. Differential overexpression of RTPZ was accompanied by that of its modulators pleiotrophin, NrCAM, tenascin, and the chondroitin sulfate proteoglycans, suggesting the importance of RTPZ signaling to WMPCs. When exposed to the RTPZ inhibitor bpV(phen), or lentiviral-shRNAi against RTPZ, WMPCs differentiated as oligodendrocytes. Conversely, when neuralin and BAMBI were antagonized by BMP4, astrocytic differentiation was induced, which was reversible by noggin. INTERPRETATION: The RTPZ and BMP pathways regulate the self-maintenance of adult human WMPCs, and can be modulated to induce their oligodendrocytic or astrocytic differentiation. As such, they provide targets by which to productively mobilize resident progenitor cells of the adult human brain. 6 samples, three biological replicates (individual patients), 2 groups (A2B5+ and unsorted cells).
Project description:Tissue repair using cell transplantation holds popular appeal. This underlines the need to understand stem cells within the target organ. Our laboratory works on the human brain. Using neurosphere methods, we and others have only been able to passage stem/progenitors a very few times with little expansion of numbers. Now we describe an efficient method for the establishment and propagation of human brain stem cells from whatever tissue samples we have tried. We describe virtually unlimited expansion of an authentic stem cell phenotype. Pluripotency markers Sox2 and Oct4 are expressed without artificial induction. For the first time, multipotency of adult human brain-derived stem cells is demonstrated beyond tissue boundaries. We characterize these cells in detail in vitro including microarray and proteomic approaches. Whilst clarification of these cells' behavior is ongoing, results so far portend well for the future repair of tissues by transplantation of an adult patient's own-derived stem cells. Grey matter and white matter: tissue, stem cells and differentiated cells compared. Total RNA from two brain biopsy sources (grey matter, white matter) from one adult human.
Project description:Glial progenitor cells (GPCs) of the adult human white matter, which express gangliosides recognized by monoclonal antibody A2B5, are a potential source of glial tumors of the brain. We used A2B5-based sorting to extract progenitor-like cells from a range of human glial tumors, that included low-grade glioma, oligodendroglioma, oligo-astrocytomas, anaplastic astrocytoma, and glioblastoma multiforme. The A2B5+ tumor cells proved tumorigenic upon orthotopic xenograft, and the tumors generated reflected the phenotypes of those from which they derived. Expression profiling revealed that A2B5+ tumor progenitors expressed a cohort of genes by which they could be distinguished from A2B5+ GPCs isolated from normal adult white matter. Most of the genes differentially expressed by glioma-derived A2B5+ cells varied as a function of tumor stage; however, a small number were invariably expressed at all stages of gliomagenesis. These glioma progenitor-associated genes included CD24, SIX1 and EYA1, which were up-regulated at all stages of gliomagenesis, and MTUS1 and SPOCK3, which were down-regulated at all stages of tumor progression. qPCR and immunolabeling confirmed the differential expression of these genes in primary gliomas, while pathway analysis permitted their segregation into differentially active signaling pathways. By comparing the expression patterns of glial tumor progenitors to their identically-isolated normal homologues, we have identified a discrete set of oncogenic pathways by which glial tumorigenesis may be both better understood, and more efficiently targeted.
Project description:In a classical view of hematopoiesis, the various blood cell lineages arise via a hierarchical scheme starting with multipotent stem cells that become increasingly restricted in their differentiation potential through oligopotent and then unipotent progenitors. We developed a cell-sorting scheme to resolve myeloid (My), erythroid (Er), and megakaryocytic (Mk) fates from single CD34+ cells and then mapped the progenitor hierarchy across human development. Fetal liver contained large numbers of distinct oligopotent progenitors with intermingled My, Er and Mk fates. However, few oligopotent progenitor intermediates were present in the adult bone marrow. Instead only two progenitor classes predominate, multipotent and unipotent, with Er-Mk lineages emerging from multipotent cells. The developmental shift to an adult 'two-tier' hierarchy challenges current dogma and provides a revised framework to understand normal and disease states of human hematopoiesis.
Project description:Tissue repair using cell transplantation holds popular appeal. This underlines the need to understand stem cells within the target organ. Our laboratory works on the human brain. Using neurosphere methods, we and others have only been able to passage stem/progenitors a very few times with little expansion of numbers. Now we describe an efficient method for the establishment and propagation of human brain stem cells from whatever tissue samples we have tried. We describe virtually unlimited expansion of an authentic stem cell phenotype. Pluripotency markers Sox2 and Oct4 are expressed without artificial induction. For the first time, multipotency of adult human brain-derived stem cells is demonstrated beyond tissue boundaries. We characterize these cells in detail in vitro including microarray and proteomic approaches. Whilst clarification of these cells' behavior is ongoing, results so far portend well for the future repair of tissues by transplantation of an adult patient's own-derived stem cells. Adult human brain stem cells from the subventricular zone, hippocampus, grey matter and white matter. Total RNA from five adult human brain biopsy sources: 3 subventricular-derived cell lines, 3 hippocampus-derived cell lines, 3 grey matter-derived cell lines and 3 white matter-derived cell lines.
Project description:OBJECTIVE: Glial progenitor cells are abundant in adult human white matter. This study was designed to identify signaling pathways regulating their self-renewal and fate. METHODS: We compared the transcriptional profiles of freshly sorted adult human white matter progenitor cells (WMPCs), purified by A2B5-based immunomagnetic sorting, with those of the white matter from which they derived. RESULTS: We identified 132 genes differentially expressed by WMPCs; these included principal components of five receptor-defined signaling pathways, represented by platelet derived growth factor receptor alpha (PDGFRA) and type 3 fibroblast growth factor receptor (FGFR3), receptor tyrosine phosphatase-beta/zeta (RTPZ), notch, and syndecan3. WMPCs also differentially expressed the bone morphogenetic protein 4 (BMP4) inhibitors neuralin and BAMBI (BMP and activin membrane-bound inhibitor), suggesting tonic defense against BMP signaling. Differential overexpression of RTPZ was accompanied by that of its modulators pleiotrophin, NrCAM, tenascin, and the chondroitin sulfate proteoglycans, suggesting the importance of RTPZ signaling to WMPCs. When exposed to the RTPZ inhibitor bpV(phen), or lentiviral-shRNAi against RTPZ, WMPCs differentiated as oligodendrocytes. Conversely, when neuralin and BAMBI were antagonized by BMP4, astrocytic differentiation was induced, which was reversible by noggin. INTERPRETATION: The RTPZ and BMP pathways regulate the self-maintenance of adult human WMPCs, and can be modulated to induce their oligodendrocytic or astrocytic differentiation. As such, they provide targets by which to productively mobilize resident progenitor cells of the adult human brain.