Effect of Coronin-1 siRNA on Phagocytosis of Mouse Macrophages

Abstract: Coronin-1 of macrophage is associated with the escaping immune killing of Mycobacterium tuberculosis (Mtb). This study was aimed to investigate the effect of pS-EGFP-SP-Coronin-1siRNA plasmid on phagocytosis of mouse macrophages. The RAW264.7 cells were transfected with the plasmid， and the expression level of Coronin-1 in macrophages before and after plasmid transfection was detected by RT-PCR and Western blot. After the plasmid transfection group cells and the control group cells were infected with Mycobacterium smegmatis respectively， the ability of phagocytosis of macrophages was evaluated by colony count of intracellular bacteria and acid fast staining of cells on cover slips， and the apoptosis level of the plasmid transfection group cells and the control group cells after phagocytosis of Mycobacterium smegmatis was detected by the flow cytometry. The results showed that the plasmid can significantly inhibit the mRNA level and protein expression of Coronin-1 in RAW264.7 cells. The number of intracellular bacteria in the plasmid transfection group cells was significantly higher than that of the control group cells after infection with Mycobacterium smegmatis for 6 h (P<0.05). The apoptosis level in the plasmid transfection group cells were significantly higher than that of the control group cells after infection with Mycobacterium smegmatis for 48 h (P<0.05). These results indicated that the pS-EGFP-SPCoronin- 1siRNA plasmid can significantly inhibit the expression of Coronin-1 in macrophages， and significantly promote phagocytosis of bacteria and the bactericidal function through apoptosis of macrophages， which lay a foundation for the development of anti-tuberculosis gene therapy targeting macrophage Coronin-1.

CSTR: 32200.14.cjcb.2018.06.0004