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Fc gamma receptor-TLR cross-talk elicits pro-inflammatory cytokine production by human M2 macrophages.

ABSTRACT: M2 macrophages suppress inflammation in numerous disorders, including tumour formation, infection and obesity. However, the exact role of M2 macrophages in the context of several other diseases is still largely undefined. We here show that human M2 macrophages promote inflammation instead of suppressing inflammation on simultaneous exposure to complexed IgG (c-IgG) and TLR ligands, as occurs in the context of diseases such as rheumatoid arthritis (RA). c-IgG-TLR ligand co-stimulation of M2 macrophages selectively amplifies production of pro-inflammatory cytokines TNF-?, IL-1? and IL-6 and promotes Th17 responses, which all play a critical role in RA pathology. Induction of pro-inflammatory cytokines on c-IgG co-stimulation mainly depends on Fc gamma receptor IIa (Fc?RIIa), which selectively amplifies cytokine gene transcription and induces caspase-1 activation. These data indicate that Fc?R-TLR cross-talk may be targeted for treatment to attenuate inflammation in RA, by restoring the anti-inflammatory function of M2 macrophages.

SUBMITTER: Vogelpoel LT

PROVIDER: S-EPMC4243215 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Fc gamma receptor-TLR cross-talk elicits pro-inflammatory cytokine production by human M2 macrophages.

Vogelpoel Lisa T C LT Hansen Ivo S IS Rispens Theo T Muller Femke J M FJ van Capel Toni M M TM Turina Maureen C MC Vos Joost B JB Baeten Dominique L P DL Kapsenberg Martien L ML de Jong Esther C EC den Dunnen Jeroen J

Nature communications 20141113

M2 macrophages suppress inflammation in numerous disorders, including tumour formation, infection and obesity. However, the exact role of M2 macrophages in the context of several other diseases is still largely undefined. We here show that human M2 macrophages promote inflammation instead of suppressing inflammation on simultaneous exposure to complexed IgG (c-IgG) and TLR ligands, as occurs in the context of diseases such as rheumatoid arthritis (RA). c-IgG-TLR ligand co-stimulation of M2 macro ...[more]

PMID: 25392121

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Fc gamma receptor-TLR cross-talk elicits pro-inflammatory cytokine production by human M2 macrophages.

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Fc gamma receptor-TLR cross-talk elicits pro-inflammatory cytokine production by human M2 macrophages.

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