Based on the stimuli and the achieved transcriptional changes, the M2 macrophages can be classified into four subdivisions - M2a, M2b, M2c, and M2d. In this assay, except for different macrophage polarization by adding certain stimuli, verification of each polarized macrophage-based on the distinctly expressed surface markers and/or produced cytokines is available. https://www.creative-biolabs.com/car-t/macrophage-polarization-assay.htm