Table 3 Overview of the main functions of M1 and M2 associated markers
From: Acute injury in the peripheral nervous system triggers an alternative macrophage response
General macrophage markers | ||
|---|---|---|
CD11b | Cluster of differentiation 11b | Expressed on all myeloid lineage cells |
F4/80 (EMR1) | EGF-like module-containing mucin-like hormone receptor-like 1 | Expressed on most tissue macrophages |
Iba1 | Ionized calcium binding adaptor molecule 1 | Expressed on macrophages (and microglia) |
M1 associated markers | ||
IFNγ | Interferon gamma | Polarize macrophages towards M1; critical for innate and adaptive immunity against viral and intracellular bacterial infections (also produced by macrophages) [40] |
IL-12p40 | Interleukin 12 subunit p40 | Pro-inflammatory cytokine; induces Th1[41], production of cytokines (mainly IFNγ) [42], stimulation cell-mediated immunity against microbial pathogens [43] |
iNOS | Inducible nitric oxide synthase | Production of nitric oxide (NO) using arginine as a substrate; defense against microorganisms [44] |
M2 associated markers | ||
Arg1 | Arginase 1 | Production of L-ornithine and urea using arginine as a substrate, first step to production of polyamines (growth factors in the nervous system) [45]; counteracts iNOS |
CDH1 | Cadherin-1 | Cell-cell adhesion [46], interaction with CD103 of regulatory T-cells [47] |
Clec7a (dectin1) | C-type lectin domain family 7, member a | Pattern recognition; non-opsonic beta-glucan receptor [48] |
FIZZ1 | Found in inflammatory zone | Lipid and sugar metabolism; angiogenesis-promoting factor [49] |
IL-4 | Interleukin 4 | Th2 effector cytokine: polarize macrophages to M2 [50]; IgE class switching, differentiation of CD4+ T-cells into Th2 cells [51] |
IL-10 | Interleukin 10 | Anti-inflammatory cytokine [52] |
IL-13 | Interleukin 13 | Th2 effector cytokine: polarize macrophages to M2; fibrosis; defense against parasite infections [53] |
MRC1 | Mannose receptor type C1 | Pattern recognition, type II response promoting effect [54] |
Rage | Receptor for advanced glycosylation end products | Pattern recognition; binds endogenous ligands such as S100B to stimulate trophic effects on neurons [55] |
Trem2 | Triggering receptor expressed on myeloid cells 2 | Pattern recognition [56]; augmentation of apoptotic neuron phagocytosis and attenuation of proinflammatory cytokine secretion [57] |
Ym1 (CH3L3) | Chitinase 3-like-3 | Weak eosinophils chemoattractant properties [58]; binds heparan sulfate, heparin, GlcN olimers; Th2 promoting effect [59] |