Dataset Information

Novel transcriptome signatures and markers defining murine macrophages at the extremes of the canonical M1 and M2 polarization spectrum

ABSTRACT: Classically (M1) and alternatively activated (M2) macrophages play distinct roles in various physiological and disease processes. Understanding the gene transcription programs that contribute to macrophage polarization along the M1/M2 spectrum may lead to new tools to detect and therapeutically manipulate macrophage phenotype. Here, we define the M1 and M2 macrophage signature through mRNA microarray. The M1 macrophage signature was defined by 629 up-regulated and 732 down-regulated genes while the M2 macrophage signature was formed by 388 up-regulated and 425 down-regulated genes. While a subset of probes was common to both M1 and M2 cells, others were exclusive to each macrophage subset. The common M1/M2 pathways were characterized by changes in various transcriptional regulators and signaling partners, including increases in Kruppel-like Factor (Klf) 4, but decreases in Klf2. To identify M1 and M2 biomarkers that help discriminate these populations, we selected genes that were increased during M1 or M2 differentiation but decreased in the opposite population. Among top novel M1-distinct genes, we identified CD38, G-protein coupled receptor 18 (Gpr18) and Formyl peptide receptor 2 (Fpr2). Among top M2 genes, we found early growth response protein 2 (Egr2) and Myc. We validated these genes by Real-Time PCR and developed a CD38/Egr2-based flow cytometry assay that discriminates between M1 and M2 macrophages. Overall, this work defines the M1 and M2 signature and identifies several novel M1 and M2 genes that may be used to distinguish and manipulate M1 and M2 macrophages.

ORGANISM(S): Mus musculus

PROVIDER: GSE69607 | GEO | 2015/12/08

SECONDARY ACCESSION(S): PRJNA285965

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Recent studies suggest the presence of both âclassically activatedâ M1 and âalternatively activatedâ M2 macrophages in human atherosclerotic tissue, yet due to the lack of validated markers the reported localization patterns of these macrophage phenotypes within plaques are ambiguous. In the present study, we searched for markers that indisputably can identify differentiated M1 and M2 macrophages independently of stimuli that affect the activation status of the two subpopulations. We used these validated markers to assess the presence of M1 and M2 macrophages in different zones of human carotid artery atherosclerotic plaques obtained from 12 patients. Using microarray and qPCR technology we show that the frequently used macrophage subpopulation markers MCP-1 and CD206 do not discriminate between M1 and M2 macrophages. However, we confirm the subtype specificity of the classical M2 marker CD163 and we report that the genes INHBA and DSP (both M1) and SEPP1 and MARCKS (both M2) are highly suitable for macrophage phenotyping. mRNA expression of the pan-macrophage marker CD68 in the shoulder zones of the plaques and in adjacent tissue segments correlated positively with mRNA expression levels of SEPP1, MARCKS and CD163 (r=0.86, 0.94 and 0.96, and r= 0.86, 0.98 and 0.69, respectively) but not with the expression of the M1 markers DSP and INHBA. In contrast, mRNA expression of CD68 in the core of the plaques correlated positively with expression of DSP and INHBA (r=0.73 and 0.49) but not with SEPP1, MARCKS and CD163. These findings suggest that M1 macrophages predominate in the core of human carotid atherosclerotic plaques while M2 macrophages prevail at the periphery of the plaque. Keywords: Expression profiling by array Monocytes from healthy volunteers were differentiated into M1 and M2 macrophages by incubation with granulocyte-macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF), respectively. After 5 days cells were exposed to oxidized LDL. Total RNA was isolated and subjected to gene expression profiling.

Dataset Information

Novel transcriptome signatures and markers defining murine macrophages at the extremes of the canonical M1 and M2 polarization spectrum

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure