小鼠6Gy全身照射后巨噬细胞对造血的抑制效应研究

Effects of macrophages on hemopoiesis after total body irradiation in mice

目的 探讨放射损伤后巨噬细胞对血细胞生成的负性调节作用。方法 昆明种雄性小鼠经 6Gy6 0 Coγ射线一次性全身照射后 ,检测辐照后 1、3、7、15d腹腔巨噬细胞 (PCMΦ)数量和吞噬墨汁的能力 ;用ELISA和放免法检测巨噬细胞培养上清TGF β1 、MIP 1α和TNFα的含量 ;将不同数量的巨噬细胞加入骨髓有核细胞中 ,观察其对CFU E和CFU GM形成的影响 ;骨髓有核细胞剔除Mac 1+ 细胞及再加入不同比例的巨噬细胞后对CFU E和CFU GM形成的影响。结果 ①放射损伤后巨噬细胞吞噬功能增强 ;培养上清TNFα、TGF β1 和MIP 1α水平升高 ;经LPS刺激后放射损伤组巨噬细胞培养上清此 3种因子的水平无显著改变。②骨髓细胞中当加入 10 %以上正常巨噬细胞时生成的CFU E和CFU GM数量明显减少 ,当加入相同比例的放射损伤巨噬细胞生成的CFU E和CFU GM数量减少更加显著。③剔除Mac 1+ 细胞后的骨髓细胞生成CFU E和CFU GM数量增加 ,当再加回巨噬细胞数量又减少。结论 放射损伤后巨噬细胞被激活 ,造血抑制活性增强 ,这可能是放射损伤骨髓造血功能受抑的原因之一。

Objective To study the effects of peritoneal macrophages on hemopoiesis after total body irradiation of gamma rays in mice. Methods Male Kumming mice were exposed to total body irradiation of 6 Gy of gamma rays from 60 Co. The number of peritoneal macrophages was counted and their ability to phagocytose ink was observed on the 1st, 3rd, 7th and 15th day after irradiation. The content of TNFα, TGF β 1 and MIP 1α in the supernatant of the culture medium of the macrophages was determined with ELISA and radioimmunoassay. Different proportions of normal and irradiated macrophages were added to bone marrow cells to observe their effects on the formation of CFU E and CFU GM. Results ①The phagocytic ability was stronger in the irradiated macrophages than in the mormal ones. The content of TNFα, TGF β 1 and MIP 1α was increased in the supernatant of the culture medium of the irradiated macrophages but showed no significant changes in that stimulated with LPS. ②The formation of CFU E and CFU GM was obviously decreased when normal macrophages was added to the bone marrow cells and it was more obviously decreased when 10% irradiated macrophages was added. ③The formation of CFU E and CFU GM was increased after the depletion of Mac 1 cells but decreased again when irradiated macrophages were added. Conclusion The decline of hemopoiesis in the bone marrow after radiation injury might be due to the fact that the radiation activated macrophages intensify their inhibition on hemopoiesis.