Project description:To investigate the genetic differencesin human AQP4-IgG group and control-IgG group , we established primary astrocytes line. We then performed gene expression profiling analysis using data obtained from RNA-seq after 48h with stimulation with human AQP4-IgG and control-IgG.
Project description:Astrocytes are specialized glial cell types of the central nervous system (CNS) with remarkably high abundance, morphological and functional diversity. Astrocytes maintain neural metabolic support, synapse regulation, blood-brain barrier integrity and immunological homeostasis through intricate interactions with other cells, including neurons, microglia, pericytes and lymphocytes. Due to their extensive intercellular crosstalks, astrocytes are also implicated in the pathogenesis of CNS disorders, such as ALS (amyotrophic lateral sclerosis), Parkinson’s disease and Alzheimer’s disease. Despite the critical importance of astrocytes in neurodegeneration and neuroinflammation are recognized, the lack of suitable in vitro systems limits their availability for modeling human brain pathologies. Here, we report the time-efficient, reproducible generation of astrocytes from human induced pluripotent stem cells (hiPSCs). Our hiPSC-derived astrocytes expressed characteristic classical markers of mature astrocytes, such as GFAP, S100b, ALDH1L1 and AQP4. Furthermore, hiPSC-derived astrocytes displayed spontaneous calcium transients and responded to inflammatory stimuli by the secretion of type A1 and type A2 astrocyte-related cytokines.
Project description:GFAP and vimentin deficiency alters gene expression in astrocytes and microglia in wild-type mice and changes the transcriptional response of reactive glia in mouse model for Alzheimer's disease. Reactive astrocytes with an increased expression of intermediate filament (IF) proteins Glial Fibrillary Acidic Protein (GFAP) and Vimentin (VIM) surround amyloid plaques in Alzheimer's disease (AD). The functional consequences of this upregulation are unclear. To identify molecular pathways coupled to IF regulation in reactive astrocytes, and to study the interaction with microglia, we examined WT and APPswe/PS1dE9 (AD) mice lacking either GFAP, or both VIM and GFAP, and determined the transcriptome of cortical astrocytes and microglia from 15- to 18-month-old mice. Genes involved in lysosomal degradation (including several cathepsins) and in inflammatory response (including Cxcl5, Tlr6, Tnf, Il1b) exhibited a higher AD-induced increase when GFAP, or VIM and GFAP, were absent. The expression of Aqp4 and Gja1 displayed the same pattern. The downregulation of neuronal support genes in astrocytes from AD mice was absent in GFAP/VIM null mice. In contrast, the absence of IFs did not affect the transcriptional alterations induced by AD in microglia, nor was the cortical plaque load altered. Visualizing astrocyte morphology in GFAP-eGFP mice showed no clear structural differences in GFAP/VIM null mice, but did show diminished interaction of astrocyte processes with plaques. Microglial proliferation increased similarly in all AD groups. In conclusion, absence of GFAP, or both GFAP and VIM, alters AD-induced changes in gene expression profile of astrocytes, showing a compensation of the decrease of neuronal support genes and a trend for a slightly higher inflammatory expression profile. However, this has no consequences for the development of plaque load, microglial proliferation, or microglial activation. 2 cell types from 6 conditions: cortical microglia and cortical astrocytes from 15-18 month old APPswe/PS1dE9 mice compared to wildtype littermates. Biological replicates: microglia from APPswe/PS1dE9, N=7, microglia from WT, N=7, astrocytes from APPswe/PS1dE9, N=4, microglia from WT, N=4
Project description:Comparison of expression data of rat forebrain astrocytes from P1, P7 acutely isolated by immunopanning or cultured with astrocytes prepared by McCarthy and de Vellis' (1980) method. Elucidating the genes induced by serum in immunopannedrat astrocytes. Three biological replicates for each sample were done. MD-astrocytes were prepared as described in McCarthy and de Vellis 1980 and harvested for mRNA after 7DIV. IP-astrocytes were isolated from P1 or P7 Sprague Dawley rats and processed for RNA immediately (IP-astrocytes P1/P7), or cultured for 7 days in HBEGF before harvesting (Cult. IP-astrocytes P1/P7). For the serum studies, we plated IP-astrocytes P7 in MD-astrocyte media containing 10% fetal calf serum immediately after isolation and cultured them for 7 days. After 7 days, the cultures were either processed for total RNA or washed 3x with dPBS and astrocyte base media with HBEGF was added. The cells were cultured for an additional 7 days and then processed for RNA. We isolated total RNA with the QIAshredder and Qiagen RNeasy Mini Kit. We used the 3’IVT Express kit for preparation of the RNA and the Rat Genome 230 2.0 Array chip (Affymetrix, Santa Clara). RT-PCR was used to elucidate the level of contamination in each cell sample.
Project description:In a previous study performed in our laboratory, the level of FGF1 RNA was found to be increased in remyelinated multiple sclerosis lesions compared to control brain (unpublished observation). Astrocytes play a key role in multiple sclerosis lesion formation. To shed light on potential FGF1-mediated functions in multiple sclerosis, the impact of FGF1 on astrocytes was investigated.