Project description:Viral infections of the CNS are of increasing concern, especially among immunocompromised populations. Rodent models are often inappropriate for studies of CNS infection, as many viruses, including JC Virus (JCV) and HIV, cannot replicate in rodent cells. Consequently, human fetal brain-derived multipotential CNS progenitor cells (NPCs) that can be differentiated into neurons, oligodendrocytes, or astrocytes, have served as a model for CNS studies. NPCs can be non-productively infected by JCV, while infection of progenitor-derived astrocytes (PDAs) is robust. We profiled cellular gene expression at multiple times during differentiation of NPCs to PDAs. Several activated transcription factors show commonality between cells of the brain in which JCV replicates and lymphocytes in which JCV is likely latent. Bioinformatic analysis determined transcription factors that may influence the favorable transcriptional environment for JCV in PDAs. This study attempts to provide a framework for understanding the functional transcriptional profile necessary for productive JCV infection. 19 Human samples: 4 Human Fetal Brain NPC 0h, 4 Human Fetal Brain NPC in Serum 1h, 4 Human Fetal Brain NPC in Serum 1d, 4 Human Fetal Brain NPC in Serum 7d, 3 Human Fetal Brain NPC in Serum 30d.
Project description:Viral infections of the CNS are of increasing concern, especially among immunocompromised populations. Rodent models are often inappropriate for studies of CNS infection, as many viruses, including JC Virus (JCV) and HIV, cannot replicate in rodent cells. Consequently, human fetal brain-derived multipotential CNS progenitor cells (NPCs) that can be differentiated into neurons, oligodendrocytes, or astrocytes, have served as a model for CNS studies. NPCs can be non-productively infected by JCV, while infection of progenitor-derived astrocytes (PDAs) is robust. We profiled cellular gene expression at multiple times during differentiation of NPCs to PDAs. Several activated transcription factors show commonality between cells of the brain in which JCV replicates and lymphocytes in which JCV is likely latent. Bioinformatic analysis determined transcription factors that may influence the favorable transcriptional environment for JCV in PDAs. This study attempts to provide a framework for understanding the functional transcriptional profile necessary for productive JCV infection.
Project description:In this study, proteomic analysis on ZIKV-infected primary human fetal neural progenitor cells (NPCs) revealed that virus infection altered levels of cellular proteins involved in NPC proliferation, differentiation and migration.
Project description:Sox2 is expressed by neural stem and progenitor cells, and a sox2 enhancer identifies these cells in the forebrains of both fetal and adult transgenic mouse reporters. We found that an adenovirus encoding EGFP placed under the regulatory control of a 0.4 kb sox2 core enhancer selectively identified multipotential and self-renewing neural progenitor cells in dissociates of human fetal forebrain. Gene expression analysis of E/sox2:EGFP-sorted neural progenitor cells, normalized to the unsorted forebrain dissociates from which they derived, revealed marked overexpression of genes within the notch and wnt pathways, and identified multiple elements of each pathway that appear selective to human neural progenitors.
Project description:Sox2 is expressed by neural stem and progenitor cells, and a sox2 enhancer identifies these cells in the forebrains of both fetal and adult transgenic mouse reporters. We found that an adenovirus encoding EGFP placed under the regulatory control of a 0.4 kb sox2 core enhancer selectively identified multipotential and self-renewing neural progenitor cells in dissociates of human fetal forebrain. Gene expression analysis of E/sox2:EGFP-sorted neural progenitor cells, normalized to the unsorted forebrain dissociates from which they derived, revealed marked overexpression of genes within the notch and wnt pathways, and identified multiple elements of each pathway that appear selective to human neural progenitors. We used adenoviral E/sox2:EGFP to transduce dissociates of the second trimester human ventricular zone (VZ)/ subventricular zone (SVZ), followed by EGFP-directed fluorescence-activated cell sorting (FACS). The sox2 isolates and unsorted controls from different gestational ages (16-19 wks, n=4) were then subject to RNA extraction and hybridization on Affymetrix microarrays.
Project description:Alexander disease (AxD) is a rare, severe neurodegenerative disorder caused by mutations in the glial fibrillary acidic protein (GFAP). While the exact disease mechanism remains unknown, existing studies suggest that the mutant GFAP influences many cellular processes, including cytoskeleton stability, mechanosensing, cell energetics, and proteasome function. While most studies have primarily focused on GFAP-expressing astrocytes, this protein is also expressed by radial glia and neural progenitor cells, prompting questions about the impact of GFAP mutations on central nervous system (CNS) development. In this study, we present an intriguing observation of an impaired differentiation of astrocytes and neurons in co-cultures of astrocytes and neurons, as well as in brain organoids, both generated from patient-derived induced pluripotent stem (iPS) cells with a GFAP (R239C) mutation. Leveraging single-cell RNA sequencing (scRNA-seq), we identified distinct cell populations and transcriptomic changes between the GFAP mutant cells and an isogenic corrected control. These findings are supported with immunocytochemistry and proteomics. In co-cultures, the AxD mutation resulted in an increased abundance of immature cells, while in organoids, we observed an altered cell differentiation and reduced abundance of astrocytes. Additionally, gene expression analysis associated the AxD mutation with increased stress susceptibility, cytoskeletal abnormalities, and altered extracellular matrix and cell-cell communication patterns. Overall, our results suggest the possibility of a faulty differentiation in human iPS cell-derived models of AxD, opening new avenues for AxD research.
Project description:The immortalized human ReNcell VM cell line represents a reproducible and easy-to-propagate cell culture system for studying the differentiation of neural progenitors. To better characterize the starting line and its differentiation, we assessed protein and phospho-protein levels over a two-week period during which ReNcell progenitors differentiated into neurons, astrocytes, and oligodendrocytes. Five of the datasets measured protein levels or states of phosphorylation based on tandem-mass-tag (TMT) mass spectrometry. Proteomic analysis revealed reproducible changes in pathways responsible for cytoskeletal rearrangement, cell phase transitions, neuronal migration, glial differentiation, neurotrophic signalling and extracellular matrix regulation. Proteomic data revealed accelerated differentiation in cells treated with the poly-selective CDK and GSK3 inhibitor kenpaullone or the HMG-CoA reductase inhibitor mevastatin, both of which have previously been reported to promote neural differentiation. These data provide in-depth information on the ReNcell progenitor state and on neural differentiation in the presence and absence of drugs, setting the stage for functional studies.
Project description:Zika virus (ZIKV) infection causes microcephaly and has been linked to other brain abnormalities. How ZIKV impairs brain development and function remains elusive. Here we systematically profiled transcriptomes of human neural progenitor cells (hNPCs) and astrocytes exposed to Asian ZIKVC, African ZIKVM, and Dengue virus (DENV). DENV causes distinct gene expression changes; and ZIKV has a broader impact on the expression of gene involved in DNA replication and repair. While overall expression profiles are similar, ZIKVC, but not ZIKVM, induces upregulation of viral response genes. Upon ZIKV infection, astrocytes exhibit more prominent transcriptome changes than hNPCs, particularly enriching genes related to inflammatory response and cytokine production pathways. Our analyses reveal cell-type- and strain-specific molecular signatures associated with ZIKV infection, and identify astrocytes as a major direct target of ZIKV. Further investigation of ZIKV-host interactions based our transcriptomic datasets may help to illuminate neural virulence determinants of ZIKV in patients. Gene Expression Analyses of the cells infected with different flaviviruses