Project description:The mechanisms underlying the specification of oligodendrocyte fate from multipotent neural progenitor cells (NPCs) in developing human brain are unknown. In this study, we sought to identify antigens sufficient to distinguish NPCs free from oligodendrocyte progenitor cells (OPCs). We investigated the potential overlap of NPC and OPC antigens using multicolor fluorescence-activated cell sorting (FACS) for CD133/PROM1, A2B5, and CD140a/PDGFaR antigens. Surprisingly, we found that CD133, but not A2B5, was capable of enriching for OLIG2 expression, Sox10 enhancer activity, and oligodendrocyte potential. As a subpopulation of CD133- positive cells expressed CD140a, we asked whether CD133 enriched bone fide NPCs regardless of CD140a expression. We found that CD133+CD140a- cells were highly enriched for neurosphere initiating cells and were multipotent. Importantly, when analyzed immediately following isolation, CD133+CD140a- NPCs lacked the capacity to generate oligodendrocytes. In contrast, CD133+CD140a+ cells were OLIG2-expressing OPCs capable of oligodendrocyte differentiation, but formed neurospheres with lower efficiency and were largely restricted to glial fate. Gene expression analysis further confirmed the stem cell nature of CD133+CD140a- cells. As human CD133+ cells comprised both NPCs and OPCs, CD133 expression alone cannot be considered a specific marker of the stem cell phenotype, but rather comprises a heterogeneous mix of glial restricted as well as multipotent neural precursors. In contrast, CD133/CD140a-based FACS permits the separation of defined progenitor populations and the study of neural stem and oligodendrocyte fate specification in the human brain. 12 samples, 4 groups (FACS-sorted cell populations),3 replicates in each group, each replicate is from a separate patient sample
Project description:The mechanisms underlying the specification of oligodendrocyte fate from multipotent neural progenitor cells (NPCs) in developing human brain are unknown. In this study, we sought to identify antigens sufficient to distinguish NPCs free from oligodendrocyte progenitor cells (OPCs). We investigated the potential overlap of NPC and OPC antigens using multicolor fluorescence-activated cell sorting (FACS) for CD133/PROM1, A2B5, and CD140a/PDGFaR antigens. Surprisingly, we found that CD133, but not A2B5, was capable of enriching for OLIG2 expression, Sox10 enhancer activity, and oligodendrocyte potential. As a subpopulation of CD133- positive cells expressed CD140a, we asked whether CD133 enriched bone fide NPCs regardless of CD140a expression. We found that CD133+CD140a- cells were highly enriched for neurosphere initiating cells and were multipotent. Importantly, when analyzed immediately following isolation, CD133+CD140a- NPCs lacked the capacity to generate oligodendrocytes. In contrast, CD133+CD140a+ cells were OLIG2-expressing OPCs capable of oligodendrocyte differentiation, but formed neurospheres with lower efficiency and were largely restricted to glial fate. Gene expression analysis further confirmed the stem cell nature of CD133+CD140a- cells. As human CD133+ cells comprised both NPCs and OPCs, CD133 expression alone cannot be considered a specific marker of the stem cell phenotype, but rather comprises a heterogeneous mix of glial restricted as well as multipotent neural precursors. In contrast, CD133/CD140a-based FACS permits the separation of defined progenitor populations and the study of neural stem and oligodendrocyte fate specification in the human brain.
Project description:Glial progenitor cells (GPCs) pervade the human brain. These cells express gangliosides recognized by MAb A2B5, and some but not all can generate oligodendrocytes. Since some A2B5+ GPCs express PDGFa receptor (PDGFRa), which is critical to oligodendrocyte development, we asked if PDGFRa-directed sorting might isolate oligodendrocyte-competent progenitors. We used FACS to sort PDGFRa+ cells from the second trimester fetal human forebrain, based on expression of the PDGFRa epitope CD140a. CD140a+ cells could be maintained as mitotic progenitors that could be instructed to either oligodendrocyte or astrocyte phenotype. Transplanted CD140a+ cells robustly myelinated the hypomyelinated shiverer mouse brain. Microarray confirmed that CD140a+ cells differentially expressed PDGFRA, NG2, OLIG1/2, NKX2.2 and SOX2. Some expressed CD9, thereby defining a CD140a+/CD9+ fraction of oligodendrocyte-biased progenitors. CD140a+ cells differentially expressed genes of the PTN-PTPRZ1, wnt, notch and BMP pathways, suggesting the interaction of self-renewal and fate-restricting pathways in these cells, while identifying targets for their mobilization and instruction. 10 samples, 5 CD140a+, and 5 CD140a- sorted samples for individual fetal human brain
Project description:Glial progenitor cells (GPCs) pervade the human brain. These cells express gangliosides recognized by MAb A2B5, and some but not all can generate oligodendrocytes. Since some A2B5+ GPCs express PDGFa receptor (PDGFRa), which is critical to oligodendrocyte development, we asked if PDGFRa-directed sorting might isolate oligodendrocyte-competent progenitors. We used FACS to sort PDGFRa+ cells from the second trimester fetal human forebrain, based on expression of the PDGFRa epitope CD140a. CD140a+ cells could be maintained as mitotic progenitors that could be instructed to either oligodendrocyte or astrocyte phenotype. Transplanted CD140a+ cells robustly myelinated the hypomyelinated shiverer mouse brain. Microarray confirmed that CD140a+ cells differentially expressed PDGFRA, NG2, OLIG1/2, NKX2.2 and SOX2. Some expressed CD9, thereby defining a CD140a+/CD9+ fraction of oligodendrocyte-biased progenitors. CD140a+ cells differentially expressed genes of the PTN-PTPRZ1, wnt, notch and BMP pathways, suggesting the interaction of self-renewal and fate-restricting pathways in these cells, while identifying targets for their mobilization and instruction.
Project description:Human fetal dissociates from 19-22 week gestational age were magnetically sorted for CD140a antigen. CD140a-defined OPCs were plated into serum free conditions and allowed to differentiate in the absence of growth factors or mitogens. RNA was extracted from cells immediately following isolation and every day for 4 days. To block differentiation, matched cells were cultured in the presence of PDGF-AA (10ng/ml). This treatment prevents the acquisition of O4-positive oligodendrocyte cell fate and delays MBP mRNA expression by human CD140a-sorted OPCs.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Single-nucleus RNA sequencing (snRNA-seq) was used to profile the transcriptome of 16,015 nuclei in human adult testis. This dataset includes five samples from two different individuals. This dataset is part of a larger evolutionary study of adult testis at the single-nucleus level (97,521 single-nuclei in total) across mammals including 10 representatives of the three main mammalian lineages: human, chimpanzee, bonobo, gorilla, gibbon, rhesus macaque, marmoset, mouse (placental mammals); grey short-tailed opossum (marsupials); and platypus (egg-laying monotremes). Corresponding data were generated for a bird (red junglefowl, the progenitor of domestic chicken), to be used as an evolutionary outgroup.