Interferon-Regulatory Factors Determine Macrophage Phenotype Polarization

Table 1

Interferon-regulator factors and macrophage polarization.

	Chromosome	Expression	Effect on macrophages	Favoured macrophage phenotype
IRF-1	5q31	Ubiquitous	Induced by IFN-γ, mediates TLR/MyD88 signaling, interacts with NF-κB (“enhanceosome”), and suppresses IL-4 promotor	M1
IRF-2	4q34	Ubiquitous	Suppression of IRF-1-mediated IFN and Cox-2 induction, complex role in LPS-induced cytokine release, and suppression of STAT1/3 signalling	Context-dependent
IRF-3	19q13	Ubiquitous	Promotes TRIF-signalling, drives IFN-γ/IL-1-mediated IL-10 secretion	M2
IRF-4	6p25	Hematopoietic cells	Induced by IL-4 via Jmjd3, inhibits MyD88 signalling by blocking IRF-5/MyD88 interaction, promotes IL-4 and IL-10 secretion	M2
IRF-5	7q32	Ubiquitous	Interacts with MyD88 needed for MyD88 signalling, drives IL-12p35 and IL-23p19 secretion	M1
IRF-6	1q32	Keratinocytes	—	—
IRF-7	11p15	Ubiquitous	Type I interferon induction	—
IRF-8	16q24	Hematopoietic cells	Induced by IFN-γ, mediates TLR-mediated induction of IFN-β, IL-12p40, IL-12p35, and iNOS, and mediates Notch and TLR signalling for M1 polarization	M1
IRF-9	14q11	Ubiquitous	Regulates type I interferon signalling	—

TLR: Toll-like receptor, IL: interleukin, IFN: interferon, Cox: cyclooxygenase, LPS: lipopolysaccharide, iNOS: inducible NO synthase.