【摘要】 目的研究巨噬细胞吞噬凋亡淋巴细胞后自噬结构的形态学特征,探讨自噬对巨噬细胞清除凋亡细胞的作用。方法用环磷酰胺诱导淋巴细胞凋亡。在扫描电子显微镜下观察巨噬细胞吞噬凋亡细胞的形态学变化,透射电镜下观察巨噬细胞内的自噬前体、自噬体和自噬溶酶体的结构特点,用图像分析仪测量自噬结构的断面面积。以单丹磺酰尸胺(MDC)染色法标记巨噬细胞的自噬体,在激光扫描共焦显微镜下观察和定量分析。结果巨噬细胞活跃地吞噬凋亡淋巴细胞、凋亡细胞核、凋亡小体或其他细胞碎片,形成异噬体。与对照组比较,吞噬凋亡细胞组的自噬细胞及其自噬体数目增多,自噬前体、自噬体和自噬溶酶体与细胞质的断面面积之比增大。许多自噬体内可见凋亡小体或其他细胞碎片,这些自噬体的体积较大,多位于细胞膜下。未观察到含有整个凋亡细胞或凋亡细胞核的自噬体。结论巨噬细胞清除凋亡淋巴细胞时自噬功能显著增强。自噬对于凋亡淋巴细胞的清除起着重要的直接和间接作用。更多还原

【Abstract】 Objective To investigate the morphological characteristics of the autophagic structures in macrophages after phagocytosis of apoptotic lymphocytes and to explore the effects of autophagy on clearance of the apoptotic cells by macrophages. Methods Apoptosis of lymphocytes was induced with cyclophosphamide.The morphological changes of macrophages phagocytizing the apoptotic cells were viewed with a scanning electron microscope.The structural features of the autophagosome precursors,autophagosomes and autophagolysosomes in macrophages were examined with a transmission electron microscope,and the cross-section areas of the autophagic structures were measured with an image analyzer.The autophagosomes of macrophages were labeled with monodansylcaolaverine(MDC) staining and quantitated using laser scanning confocal microscopy.Results Macrophages actively phagocytized the apoptotic lymphocytes,apoptotic nuclei,apoptotic bodies and other cell debris to form heterophagosomes.When compared with the control group,numbers of autophagic cells and autophagosomes in these cells increase in the group of macrophages that engulfed the apoptotic cells.In addition,the ratios of the cross-sectional areas of the autophagic structures to that of the cytoplasm of the macrophages were greater.There were also apoptotic bodies or other cell debris in many the autophagosomes,and these autophagosomes were large and near the cell membrane.Autophagosomes containing the whole apoptotic cell or apoptotic nucleus were not observed.Conclusion The autophagic abilities of macrophages were significantly enhanced when the cells removed the apoptotic lymphocytes.Autophagy also plays an important direct or indirect roles in clearance of the apoptotic lymphocytes by macrophages.更多还原