Project description:We use microarray analysis to compare the expression profiles of glioma-associated microglia/macrophages and naive control cells. Samples were generated from CD11b+ MACS-isolated cells from naïve and GL261-implanted C57BL/6 mouse brains.
Project description:Splenic long-lived plasma cells (PCs) are abnormally numerous and deleterious in systemic autoimmune diseases, yet how they accumulate remains poorly understood. We demonstrate here that a pathological role of spleen-derived CD11b+Gr-1+ myeloid cells (SPMCs) underpins the accumulation of splenic long-lived PCs in a lupus-prone model. SPMCs were a mixture of granulocytic and monocytic myeloid-derived suppressor cells (MDSCs) that were expanded and acquired proinflammatory phenotypes in situ during lupus progression. By promoting the development of IFN--secreting and follicular helper T cells, SPMCs licensed CD4+ T cells to be pathologic activators of SPMCs and PCs. SPMCs also directly promoted the survival of PCs by providing B-cell activating factor of the TNF family. The frequency of SPMCs correlated with that of splenic long-lived PCs. Depletion of CD11b+Gr-1+ cells reduced autoantibody production. Thus, our findings suggest that SPMCs expanded in situ establish a positive feedback loop with CD4+ T cells, leading to accumulation of long-lived PCs which exacerbate lupus autoimmunity.
Project description:We extracted RNA of sorted splenic CD11b+Gr-1+ cells and performed microarray analyses. Total RNA was isolated using the manufacturer’s recommended protocol for RNeasy (Qiagen, Valencia, CA). Isolated RNA was quantified, and quality was assessed using an Agilent A 2100 BioAnalyzer with the RNA NanoChip (Agilent, Andover, MA). We used 2μg of total RNA to make single-stranded antisense cDNA with the NuGEN Technologies (San Carlo, CA) Ovation Biotin System in accordance with the manufacturer’s directions. Labeled targets were hybridized to Affymetrix (Santa Clara, CA) MOE430 2.0 GeneChip microarrays for 16h at 45°C. The arrays were washed and scanned according to Affymetrix standard protocols. We used microarrays to detail the global gene expression of CD11b+Gr-1+ cells from the control mice and the clarithromycin-treated mice, and identified distinct classes of up-regulated genes during this process.
Project description:Differentially expressed genes of CD11b+Gr-1+ immature myeloid cells (IMCs) in the bone marrow and colonic tumor setting of histidine decarboxylase (HDC)-KO mice were examined by microarray (Affymetrix Mouse 430.2 array). Myeloid differentiation-related candidate genes were sought to be isolated and functionally studied. Total RNA of HDC-expressing CD11b+Gr-1+ IMCs of bone marrow were extracted from HDC-EGFP and HDC-EGFP/HDC-KO mice (3 mice in each group). CD11b+Gr-1+ myeloid-derived suppressor cells (MDSCs) of colon tumor were sorted from 10-12 colon tumors of WT and HDC-KO mice (5 mice in each group), and pooled to extract total RNA for microarray studies. Two technical replicates for each of the four groups. Four sets of comparisons were performed to screen for upregulated or downregulated genes in the HDC-KO CD11b+Gr-1+ IMCs or MDSCs (experiment group) compared to the WT group: (1) HDC-expressing CD11b+Gr-1+ IMCs of bone marrow of HDC KO mice compared to bone marrow IMCs of WT mice; (2) CD11b+Gr-1+ MDSCs in tumors of HDC-KO mice compared to WT mice; (3) CD11b+Gr-1+ MDSCs of WT colon tumors compared to IMCs in the WT bone marrow; and (4) CD11b+Gr-1+ MDSCs of colon tumors of HDC-KO mice compared to IMCs in the bone marrow of HDC-KO mice.