巨噬细胞是多细胞生物体内吞噬能力最强的细胞。巨噬细胞吞噬过程大致分为四个环节：（1）巨噬细胞表面受体识别病原体，并与之结合；（2）巨噬细胞形成吞噬杯包裹病原体，形成吞噬体；（3）进入细胞的吞噬体与胞内溶酶体结合；（4）溶酶体降解病原体。 许多因素影响巨噬细胞的吞噬功能。IFN-γ作为一种重要的细胞因子，在天然免疫中发挥重要作用。过去的许多研究表明IFN-γ作用于巨噬细胞可明显提高细胞吞噬功能。但同时，另一些研究却发现IFN-γ将削弱巨噬细胞吞噬能力。 为了验证IFN-γ对巨噬细胞吞噬功能的影响，本次研究提取小鼠腹腔巨噬细胞，分别研究IFN-γ作用后，巨噬细胞对大肠杆菌（E.Coli）、鸡红细胞（cRBC）吞噬能力的变化。结果表明：（1）随着吞噬时间的延长，巨噬细胞对大肠杆菌及鸡红细胞的吞噬率均上升；（2）IFN-γ处理组与对照组相比，巨噬细胞对大肠杆菌的吞噬率下降，但变化不大；（3）IFN-γ处理组与对照组相比，巨噬细胞对鸡红细胞（cRBC）吞噬率显著降低。本研究结果表明，IFN-γ处理后，巨噬细胞吞噬功能受到抑制。

Macrophage is the strongest phagocyte in multicellular organisms, whose phagocytosis typically includes four steps: (1) Pathogens are recognized and bound by receptors on the surface of macrophages; (2) macrophages form phagocytic cup to wrap pathogens thus form phagososmes; (3) phagosomes bind with lysosomes; (4) pathogen is degraded by lysosomes. Lots of factors influence phagocytosis. IFN-γ, one important cytokine, plays a crucial role in innate immunity. Most previous researches showed that IFN-γ significantly promoted macrophage phagocytosis. But some other stated that IFN-γ attenuated phagocytosis. In order to test the result，I took peritoneal exudate macrophages (PEMs) from mice, to check the effect of IFN-γ on phagocytosis of chicken red blood cells (cRBC) and E.Coli. Results show that: (1) The phagocytosis rate of macrophages went up as the time for phagocytosis went by; (2) IFN-γ attenuated macrophages’ phagocytosis on E.Coli, as the phagocytosis rate of macrophages treated with IFN-γ dropped from that of the control, but the difference is not significant; (3) IFN-γ attenuated macrophages’ phagocytosis on cRBC, as the phagocytosis rate of macrophages treated with IFN-γ significantly dropped from that of the control. According to these results, IFN-γ attenuated macrophages’s phagocytosis in this study.