fig2

Figure 2. The M1/M2 paradigm in the central nervous system. Transcriptional regulators of M1 and M2 activation of microglia and mechanisms of their stimulation/inhibition. Resting microglia are stimulated by interferon (IFN)-γ, lipopolysaccharide (LPS), and/or granulocyte-macrophage colony-stimulating factor (GM-CSF) to classical activation into M1 microglia, and by macrophage colony-stimulating factor (M-CSF), IL-4, IL-10, and transforming growth factor (TGF)-β for alternative activation into M2 microglia, producing pro-inflammatory and anti-inflammatory cytokines, respectively. In a well-balanced M1/M2 condition, there will be an adequate resolution of the inflammatory process. TNF-α: Tumour necrosis factor α; CD206: macrophage mannose receptor type 1 (adapted from Subramaniam et al.^[9]).