Opposing macrophage-polarization programs show extensive epigenomic and transcriptional cross-talk
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE84520 | GEO | 2017/03/02
SECONDARY ACCESSION(S): PRJNA329530
REPOSITORIES: GEO
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Project description:Stimulation of macrophages with interferon-γ (IFN-γ) and interleukin 4 (IL-4) triggers distinct and opposing activation programs. During mixed infections or cancer, macrophages are often exposed to both cytokines, but how these two programs influence each other remains unclear. We found that IFN-γ and IL-4 mutually inhibited the epigenomic and transcriptional changes induced by each cytokine alone. Computational and functional analyses revealed the genomic bases for gene-specific cross-repression. For instance, while binding motifs for the transcription factors STAT1 and IRF1 were associated with robust and IL-4-resistant responses to IFN-γ, their coexistence with binding sites for auxiliary transcription factors such as AP-1 generated vulnerability to IL-4-mediated inhibition. These data provide a core mechanistic framework for the integration of signals that control macrophage activation in complex environmental conditions.
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Project description:The M1 and the M2 macrophage polarization programs (activated by IFNγ and IL-4, respectively) lie at the opposite edges of a continuum of activation states but are frequently co-activated during co-infections and in cancer despite controlling divergent functional responses. Whether these two programs are mutually exclusive, how they influence each other, and whether one represents the prevailing response, are all open questions. Co-administration of IFNγ and IL-4 exerted complex inhibitory effects over the M1 and M2 programs at the level of both epigenomic and transcriptional changes. Computational data mining and validation analyses revealed the molecular basis of the differential sensitivity of genes and cis-regulatory elements to the antagonistic effects of the opposite stimulus. For instance, while STAT1 and IRF motifs were associated with robust and IL-4-resistant responses to IFNγ, their coexistence with binding sites for some auxiliary transcription factors such as AP-1, generated vulnerability to IL-4-mediated inhibition. These data provide a core mechanistic framework for the integration of signals that control macrophage activation and the starting point for understanding macrophage responses in complex environmental conditions
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Project description:The M1 and the M2 macrophage polarization programs (activated by IFNγ and IL-4, respectively) lie at the opposite edges of a continuum of activation states but are frequently co-activated during co-infections and in cancer despite controlling divergent functional responses. Whether these two programs are mutually exclusive, how they influence each other, and whether one represents the prevailing response, are all open questions. Co-administration of IFNγ and IL-4 exerted complex inhibitory effects over the M1 and M2 programs at the level of both epigenomic and transcriptional changes. Computational data mining and validation analyses revealed the molecular basis of the differential sensitivity of genes and cis-regulatory elements to the antagonistic effects of the opposite stimulus. For instance, while STAT1 and IRF motifs were associated with robust and IL-4-resistant responses to IFNγ, their coexistence with binding sites for some auxiliary transcription factors such as AP-1, generated vulnerability to IL-4-mediated inhibition. These data provide a core mechanistic framework for the integration of signals that control macrophage activation and the starting point for understanding macrophage responses in complex environmental conditions
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Project description:Opposing macrophage-polarization programs show extensive epigenomic and transcriptional cross-talk
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