Monocyte Differentiation towards Protumor Activity Does Not Correlate with M1 or M2 Phenotypes

Figure 3

Characterization of M1- and M2-related phenotypes. Median fluorescence intensity corresponding to (a) M1-related markers TNF-α, IDO enzyme, CCR7, and CD86 and (b) M2-related markers IL-10, arginase I, CD36, and CD163, found in cells harvested from all different polarizing treatments and controls and analyzed by flow cytometry. For THP-1, mock: no stimulated cells; PMA: PMA-only control; M1: PMA + LPS + INF-γ; M2: PMA + IL-4 + IL-13; and M2 w/o PMA: IL-4 + IL-13. For U937, mock: no stimulated cells; PMA: PMA-only control; M1: PMA + LPS + INF-γ; M2-A: PMA + IL-4 + IL-13; M2-B: PMA + M-CSF; and M2-C: IL-4 + IL-13. For primary monocytes, mock: no stimulated cells; M1: GM-CSF + LPS + INF-γ; and M2: M-CSF + IL-4 + IL-13. Asterisks and bars denote statistical significance between conditions. Significant differences () found were as follows: in THP-1 cells CD86, M1 versus M2; IL-10, mock versus all the rest of the conditions; arginase I, M1 versus PMA and versus M2 without PMA; CD163, PMA versus all the rest of the conditions and M2 versus M2 without PMA. In U937 cells IDO, M2-A versus mock and versus M2-C; CD86, (PMA, M1, M2-A, and M2-B) versus mock and M2-C; CD163, M1 versus mock and versus M2-C. In primary monocytes IDO and CD86 were significantly different in M1 versus mock and versus M2.