Project description:To examine changes in gene expression that might occur in CNS glial cells in response to the secreted products of immune cells, we used gene array analysis to assess the early effects of different cytokine mixtures on rat mixed CNS glia in culture. We compared effects at 6 hours of cytokines typical of Th1 and Th2 lymphocytes, and monocyte marophages (M/M).. We found unique patterns of changes in gene expression for each of the three cytokine mixtures, including changes in immune-related molecules, neurotrophins, growth factors, proteins involved in axon/glial interactions, ion channels, neurotransmitters, mitochondrial function and apoptosis. These changes may have relevance in neuroprotective or damaging mechanisms in neurodegenerative diseases such as multiple sclerosis, specifically with regard to formation, repair or inhibition of lesion formation. Experiment Overall Design: Mixed CNS glia cultures from newborn rat brain were treated for 6 hours with cytokine mixtures representative of Th1, Th2 or monocyte/macrophage cytokines
Project description:Objective: Brain tumors (gliomas) contain large populations of infiltrating macrophages and recruited microglia, which in experimental murine glioma models promote tumor formation and progression. Among the barriers to understanding the contributions of these stromal elements to high-grade glioma (glioblastoma; GBM) biology is the relative paucity of tools to characterize infiltrating macrophages and resident microglia. In this study, we leveraged multiple RNA analysis platforms to identify new monocyte markers relevant to GBM patient outcome. Methods: High-confidence lists of mouse resident microglia- and bone marrow-derived macrophage-specific transcripts were generated using converging RNA-seq and microarray technologies and validated using qRT-PCR and flow cytometry. Expression of select cell surface markers was analyzed in brain-infiltrating macrophages and resident microglia in an induced GBM mouse model, while allogeneic bone marrow transplantation was performed to trace the origins of infiltrating and resident macrophages. Glioma tissue microarrays were examined by immunohistochemistry, and the Gene Expression Omnibus (GEO) database was queried to determine the prognostic value of identified microglia biomarkers in human GBM. Results: We generated a unique catalog of differentially-expressed bone marrow-derived monocyte and resident microglia transcripts, and demonstrated that brain-infiltrating macrophages acquire F11R expression in GBM and following bone-marrow transplantation. Moreover, mononuclear cell F11R expression positively correlates with human high-grade glioma and additionally serves as a biomarker for GBM patient survival, regardless of GBM molecular subtype. Significance: These studies establish F11R as a novel monocyte prognostic marker for GBM critical for defining a subpopulation of stromal cells for future potential therapeutic intervention. Total RNA was isolated from three independently-generated sets of flow sorted bone marrow monocytes (CD11b+ CD45high CD115+ Ly6G- cells) and brainstem microglia (CD11b+ CD45low CD115low Ly6G- cells) for Illumina RNA-Seq, and two additional pools were subsequently generated and submitted for Affymetrix Mouse Exon 1.0ST microarray. Two of the RNA-Seq samples were additionally analyzed by the microarray, for a total of 6 samples (3 monocyte, 3 microglia) in each platform. Data outputs were analyzed by two analysis methods each (RNA-Seq data: ALEXA-Seq and Cufflinks; microarray data: Partek and Aroma). All four lists were merged into a new high-confidence gene list of transcripts that were significantly differentially expressed (DE) in three out of the four analyses. In this dataset, we includeRNA-Seq data obtained from flow sorted mouse bone marrow monocytes and brainstem microglia.
Project description:Objective: Brain tumors (gliomas) contain large populations of infiltrating macrophages and recruited microglia, which in experimental murine glioma models promote tumor formation and progression. Among the barriers to understanding the contributions of these stromal elements to high-grade glioma (glioblastoma; GBM) biology is the relative paucity of tools to characterize infiltrating macrophages and resident microglia. In this study, we leveraged multiple RNA analysis platforms to identify new monocyte markers relevant to GBM patient outcome. Methods: High-confidence lists of mouse resident microglia- and bone marrow-derived macrophage-specific transcripts were generated using converging RNA-seq and microarray technologies and validated using qRT-PCR and flow cytometry. Expression of select cell surface markers was analyzed in brain-infiltrating macrophages and resident microglia in an induced GBM mouse model, while allogeneic bone marrow transplantation was performed to trace the origins of infiltrating and resident macrophages. Glioma tissue microarrays were examined by immunohistochemistry, and the Gene Expression Omnibus (GEO) database was queried to determine the prognostic value of identified microglia biomarkers in human GBM. Results: We generated a unique catalog of differentially-expressed bone marrow-derived monocyte and resident microglia transcripts, and demonstrated that brain-infiltrating macrophages acquire F11R expression in GBM and following bone-marrow transplantation. Moreover, mononuclear cell F11R expression positively correlates with human high-grade glioma and additionally serves as a biomarker for GBM patient survival, regardless of GBM molecular subtype. Significance: These studies establish F11R as a novel monocyte prognostic marker for GBM critical for defining a subpopulation of stromal cells for future potential therapeutic intervention. Total RNA was isolated from three independently-generated sets of flow sorted bone marrow monocytes (CD11b+ CD45high CD115+ Ly6G- cells) and brainstem microglia (CD11b+ CD45low CD115low Ly6G- cells) for Illumina RNA-Seq, and two additional pools were subsequently generated and submitted for Affymetrix Mouse Exon 1.0ST microarray. Two of the RNA-Seq samples were additionally analyzed by the microarray, for a total of 6 samples (3 monocyte, 3 microglia) in each platform. Data outputs were analyzed by two analysis methods each (RNA-Seq data: ALEXA-Seq and Cufflinks; microarray data: Partek and Aroma). All four lists were merged into a new high-confidence gene list of transcripts that were significantly differentially expressed (DE) in three out of the four analyses. In this dataset, we include exon expression data obtained from flow sorted mouse bone marrow monocytes and brainstem microglia.
Project description:Infiltrating monocyte derived macrophages (MDMs) and resident microglia dominate CNS injury sites. We show that MDMs and microglia can directly communicate to modulate each other’s function. Also, the presence of MDMs in CNS injury suppresses microglia-mediated phagocytosis and inflammation. We suggest that macrophages infiltrating the injured CNS provide a mechanism to control acute and chronic microglia-mediated inflammation, which could otherwise drive damage in a variety of CNS conditions. To understand the global effects of macrophage communication to microglia, we transcriptionally profiled activated adult mouse microglia in the presence or absence of macrophages with and without an inflammatory stiumulus (LPS)
Project description:We investigated the gene expression profile of monocyte-derived macrophages and microglia following spinal cord injury. Moreover, we investigated the gene expression profole of M-CSF induced macrophages and new-born derived microglia following TGFb1 treatment. monocyte-derived macrophages and microglia following spinal cord injury M-CSF induced macrophages and new-born derived microglia following TGFb1 treatment
Project description:The aim of the present study was to analyze four different in vitro models of the murine BBB for expression and possible secretion of major basement membrane proteins from murine BCECs (mBCECs). The mBCECs and pericytes were isolated from brains of adult C57BL/6 mice, and glial cells (mainly astrocytes and microglia) were prepared from cerebral cortices of newborn C57BL/6 mice. The mBCECs were grown as mono-culture, in co-culture with pericytes or mixed glial cells, or as a triple-culture with both pericytes and mixed glial cells.
Project description:There is evidence that microglia interact with infiltrating Th1 and Th17 cells and this interaction results in mutual activation. However, the potential of a distinct cytokine milieu generated by these effector T cell subsets to activate microglia is poorly understood. In this study, we tested the ability of factors secreted by Th1 and Th17 cells to induce microglial activation. Interestingly, we found that only Th1-associated factors had the potential to activate microglia while the Th17-associated factors as well as direct contact of Th17 cells with microglia only had a minimal effect. Further Th1-derived factors triggered a proinflammatory M1-type gene expression profile in microglia Microglia harvested from mixed glial cultures were treated with supernatants from Th1- or Th17 cultures. Microglia cultured in medium was used as controls. At 16h post treatment RNA was isolated from the microglia and probed on Agilent´s murine 4x44k microarrays. RNA isolated from four independent experiments were used for the gene expression profiling. Microglia, Th1, Th17
Project description:Gene profiling of CNS-derived microglia vs splenic CD11b+Ly6C+ monocyte subsets deom adult mice Gene array identified 1572 genes that were enriched in microglia vs. 611 monocyte enriched genes with a greater than 5-fold difference (P<0.001). Gene profiling of CD11b+CD45Low microglia isolated from the CNS and CD11b+Ly6C+ monocyte subsets isolated from the spleen of naM-CM-/ve adult mice.
Project description:Macrophage distribution density is tightly regulated within the body, yet the importance of macrophage crowding during in vitro culture is largely unstudied. Using a human induced pluripotent stem cell (iPSC)-derived macrophage model of tissue resident macrophages, we demonstrate how increasing macrophage culture density changes their morphology and phenotype before and after inflammatory stimulation. In particular, density drives changes in macrophage inflammatory cytokine and chemokine secretion in both resting and activated states. This density regulated inflammatory state is also evident in blood monocyte derived-macrophages, the human monocytic THP-1 immortalized cell line, and iPSC-derived microglia. A potential cause we identify are anti-inflammatory products in the culture supernatant accumulating as density increases. However, the precise mechanism remains unknown. Our findings highlight cell plating density as an important but frequently overlooked consideration of in vitro macrophage research relevant to a variety of fields ranging from basic macrophage cell biology to disease studies.