Table 1.

Important features that help in differentiating M1 from M2 macrophages

Factors	M1 Macrophage	M2 Macrophage
Action	Pro-inflammatory, anti-microbial	Anti-inflammatory, Induce extracellular matrix
Action in tumor-microenvironment	Anti-tumorigenic	Pro-tumorigenic
Activation	Classical (Th1)	Alternative (Th2)
Stimuli	IFN-y, LPS, GM-CSF	IL-4, IL-13, M-CSF, Glucocorticoids
Cytokines and chemokines release	IFN-γ, IL-8, TNF-α, IL-1β, RANTES (CCL5), CXCL10	IL-10, IL-13, CCL17, CCL18, CCL22
Antigen presentation	Yes	No
Nitric oxide and ROS production	High	Low