Fig. 3. Differentiation of THP-1 human monocytic cells to M0 using PMA followed by LPS/INF or IL-4/IL-13 to induce M1 or M2, respectively. (a) The morphology of PMA-stimulated THP-1 (M0) show adherent cells with a slightly rounded shape while the polarized M1 and M2 macrophages show spindle shape morphology. (b–d) Flow cytometry histograms for surface expression of CD68, CD206, and CD86. Red line: isotype control; blue line: specific staining. One representative histogram is shown. Median of fluorescence intensity (MFI) values is given within graphs and represents the mean ± SE obtained from three independent experiments.