ABSTRACT
Objective:To study the characteristics of macrophage lineage model polarized to adapt to the tumor micro-environment (TME) for further research on the plasticity of macrophages in TME.Methods:Bone marrow cells from transgenic Foxn1 nu.B6-CAG-EGFP/SU mice were induced by colony-stimulating factor 1 (CSF-1), IFN-γ+ LPS and IL-4 to differentiate into M0, M1 and M2 macrophages, respectively. Green fluorescent protein (GFP) was observed under inverted fluorescence microscope. Immunocytochemical staining was used to detect the marker and polarization-related proteins of macrophages. Moreover, the macrophages were co-cultured with human glioma stem cell SU3 for further analysis. Results:The bone marrow-derived M0, M1 and M2 macrophages all showed strong green fluorescence under inverted fluorescence microscope. The inherent plasticity of the macrophages could be observed under ordinary microscope with Wright-Giemsa staining. Immunocytochemical staining showed that CD11C and CD206 markers were observed on M0, M1 and M2 macrophages, while CD68 was only expressed on M1 macrophages. Moreover, the staining was strongly positive for CSF-1 and CSF-1R on M0, M1 and M2 macrophages. Green fluorescent cell infiltration and phagocytic reaction were observed in the co-cultured stem cell spheres.Conclusions:The bone marrow-derived macrophage lineage including M0, M1 and M2 subtypes with the inherent plasticity was successfully prepared using transgenic nude mice expressing GFP. The three subtypes expressed the common marker and polarization-related proteins, and had the phagocytic activity, suggesting that they could be used to study the interaction between tumor cells and macrophages, especially in tracer studies.