Fig. 1

Human THP-1 monocyte differentiation into M1 and M2 macrophages. a The morphology of M0 (non-polarized THP-1 cells) and the expression of CD14 as measured by flow cytometry. b Confocal microscopy showing the distinct morphology of THP-1–derived M1 and M2 macrophages stained with DAPI (blue) and with antibodies against CD68 (green). c Flow cytometry demonstrated cell surface expression of CD86 and CD206 in the M0, M1, and M2 populations. d and e The mRNA expression levels of M1 and M2 macrophage markers were measured by QT-PCR. Data are presented as the mean ± SEM from three independent experiments. All results show the relative fold change compared to M0 (non-polarized THP-1 cells). *p < 0.05, **p < 0.01, and n.s. = no significance. IL, interleukin; TNF-α, tumor necrosis factor-α; iNOS, inducible nitric oxide synthase; CCR, chemokine receptor; CCL, C-C motif chemokine; MMP, matrix metalloproteinase