. 2020 Jul 22;11(31):8231–8239. doi: 10.1039/d0sc02792h

Mechanisms and effects of in vitro macrophage polarization of macrophages via different cytokines.

Polarization stimulus	Mechanism	Surface marker change	Resulting phenotype
Lipopolysaccharide (LPS)	Binds TLR 4, induces secretion of pro-inflammatory cytokines³⁸	Increased expression levels of MHC-II, CD80, CD86; decreased levels of MRC1 or Fc-γ RII³⁹	M1
Interferon-γ (IFN-γ)	Binds IFN-γ receptor⁴⁰
Combo (LPS + IFN-γ)	Synergizes LPS and IFN-γ
Interleukin 4 (IL-4)	Binds IL-4Rα and IL-2R, down-regulates proinflammatory mediators^1,32	Decreased expression of CD14 and CCR5;⁴¹ regulation of MHC-II, β2 integrins, chemokine CCL22/MDC⁴²	M2a
Interleukin 10 (IL-10)	Deactivates macrophages by inhibiting production of pro-inflammatory cytokines¹	Down-regulation of MHC II and co-stimulatory molecules¹	M2c