Table I.
Markers of M1 and M2 microglia.
| Phenotype | Marker | Type | Effect | (Refs.) | Author, year |
|---|---|---|---|---|---|
| M1 | IL-1β | Cytokine | Proinflammatory | (25) | Zhu et al, 2019 |
| IL-6 | Cytokine | Proinflammatory | (59) | Shu et al, 2016 | |
| TNF-α | Cytokine | Proinflammatory | (25) | Zhu et al, 2019 | |
| iNOS | Metabolic enzyme | Oxidative damage | (59) | Shu et al, 2016 | |
| ROS | Metabolite | Oxidative damage | (7) | Xu et al, 2018 | |
| CD11b | receptor | Induce proinflammatory signaling | (37,81) | Liu et al, 2018; Hyakkoku et al, 2010 | |
| CD16 | Receptor | Induce proinflammatory signaling | (38) | Jiang et al, 2018 | |
| CD32 | Receptor | Induce proinflammatory signaling | (37) | Liu et al, 2018 | |
| CD68 | Receptor | Induce proinflammatory signaling | (27) | Boddaert et al, 2018 | |
| CD86 | Receptor | Induce proinflammatory signaling | (44) | Hu et al, 2012 | |
| NF-кB | Transcription | Induce M1 phenotype, elevate the expression of proinflammatory cytokines | (16) | Yang et al, 2019 | |
| STAT1 | Transcription | Elevate the expression of NF-κB | (70) | Butturini et al, 2019 | |
| STAT3 | Transcription | Elevate the expression of NF-κB | (72) | Ding et al, 2019 | |
| Hv1 | Ion channel protein | Elevate the expression of ROS and NF-κB, induce M1 phenotype | (94,96) | Tian et al, 2016; Yu et al, 2018 | |
| Kv1.3 | Ion channel protein | Proinflammatory, induce M1 phenotype | (83,97) | Di Lucente et al, 2018; Nguyen et al, 2017 | |
| H19 | Gene | Proinflammatory, induce M1 phenotype | (98) | Wang et al, 2017 | |
| miRNA-155 | Gene | Proinflammatory, induce M1 phenotype | (18) | Zheng et al, 2018 | |
| M2 | IL-4 | Cytokine | Anti-inflammatory, induce M2 phenotype | (23) | Liu et al, 2016 |
| IL-10 | Cytokine | Anti-inflammatory | (25) | Zhu et al, 2019 | |
| TGF-β | Cytokine | Anti-inflammatory, regeneration | (44) | Hu et al, 2012 | |
| Ym1/2 | Protein | Anti-inflammatory, regeneration | (25) | Zhu et al, 2019 | |
| Arg-1 | Protein | Anti-inflammatory, regeneration | (44) | Hu et al, 2012 | |
| CCL22 | Chemokine | Recruits regulatory T cells | (44) | Hu et al, 2012 | |
| CD206 | Receptor | Induce anti-inflammatory signaling | (39) | Jin et al, 2014 | |
| STAT6 | Transcription | Inhibit the expression of NF-κB | (74) | Yang et al, 2017 | |
| Nrf2 | Transcription | Anti-inflammatory, antioxidant stress | (7) | Xu et al, 2018 | |
| PPARγ | Transcription | Inhibit the expression of NF-κB, promote the expression of Nrf2 | (26,78) | Liu et al, 2018; Cai et al, 2017 | |
| miRNA-124 | Gene | Anti-inflammatory, induce M2 phenotype | (99) | Hamzei et al, 2016 | |
| FAM19A3 | Gene | Anti-inflammatory, induce M2 phenotype | (100) | Shao et al, 2015 |
IL, interleukin; TNF-α, tumor necrosis factor-α; iNOS, inducible nitric oxide synthase; miRNA, microRNA; ROS, reactive oxygen species; CD11b, integrin alpha-M; CD16, low affinity immunoglobulin gamma Fc region receptor III-A; CD32, low affinity immunoglobulin gamma Fc region receptor III-b; CD68, cluster of differentiation 68; CD86, T-lymphocyte activation antigen CD86; CD206, macrophage mannose receptor 1; STAT, signal transducer and activator of transcription; H19, H19 imprinted maternally expressed transcript; TGF-β, transforming growth factor-β; Ym1/2, chitinase-3-like protein 3; Arg-1, arginase-1; CCL22, C-C motif chemokine ligand 22; Nrf2, nuclear factor erythroid 2-related factor 2; PPARγ, Peroxisome proliferator-activated receptor γ; FAM19A3, chemokine-like protein TAFA-3.