Rama R, Sánchez J, Octave J N
International Institute of Cellular and Molecular Pathology, Brussels, Belgium.
Biochim Biophys Acta. 1988 Jan 18;968(1):51-8. doi: 10.1016/0167-4889(88)90043-2.
The reticuloendothelial system is responsible for removing old and damaged erythrocytes from the circulation, allowing iron to return to bone marrow for hemoglobin synthesis. Cultured bone marrow macrophages were loaded with 59Fe-labelled erythroblasts and iron mobilization was studied. After erythroblast digestion, iron taken up by macrophages was found in ferritin as well as in a low-molecular-weight fraction. The analysis of iron mobilization from macrophages shows: (1) the iron was mobilized as ferritin. (2) A higher mobilization was observed when apotransferrin was present in the culture medium. (3) In the presence of apotransferrin in the culture medium, part of the iron was found as transferrin iron. (4) Iron transfer from ferritin to apotransferrin was observed in a cell-free culture medium and this process was temperature independent. The results indicate that after phagocytosis of 59Fe-labelled erythroblasts by macrophages, iron is mobilized as ferritin. In the plasma, this iron can be transferred to apotransferrin.
网状内皮系统负责从循环中清除衰老和受损的红细胞，使铁返回骨髓用于血红蛋白合成。用59Fe标记的成红细胞加载培养的骨髓巨噬细胞，并研究铁的动员情况。成红细胞消化后，巨噬细胞摄取的铁存在于铁蛋白以及低分子量部分中。巨噬细胞铁动员分析表明：（1）铁以铁蛋白形式被动员。（2）当培养基中存在脱铁转铁蛋白时，观察到更高的动员率。（3）在培养基中存在脱铁转铁蛋白的情况下，部分铁以转铁蛋白铁的形式存在。（4）在无细胞培养基中观察到铁从铁蛋白转移到脱铁转铁蛋白，且该过程与温度无关。结果表明，巨噬细胞吞噬59Fe标记的成红细胞后，铁以铁蛋白形式被动员。在血浆中，这种铁可转移到转铁蛋白。
