小鼠出生后早期耳蜗柯蒂氏器巨噬细胞形态的变化

目的 揭示小鼠出生后早期耳蜗柯蒂氏器是否存在巨噬细胞及柯蒂氏器巨噬细胞形态和分布的变化.方法 选1～4周龄的C57BL/6J小鼠,解剖取耳蜗基底膜.CD45抗体(一种全白细胞标记物)染色耳蜗基底膜,F4/80(巨噬细胞专有蛋白标记物)确认巨噬细胞,碘化丙锭标记细胞核,荧光显微镜下观察CD45染色阳性细胞的形态和分布变化...

Morphological Changes of Macrophages in the Organ of Corti in Early Postnatal Mice

Objective To determine whether macrophages are present in the organ of Corti,and their changes in morphology and distribution during early postnatal cochlear development in mice.Methods Cochleae were collected from C57BL/6J mice at ages of postnatal 1-4 weeks.The basilar membrane was immunolabeled with an antibody against CD45,a receptor tyrosine phosphatase presenting on all hematopoietic/bone marrow derived leukocytes.Macro‐phages were confirmed using F4/80,a macrophage-specific marker.Propidium iodide(PI)was used to label the nucleus.Morphology and distribution of CD45 and F4/80 staining positive cells were observed under a fluorescence microscopy.Results CD45 staining positive cellular structures were identified on the scala media side of the basilar membrane during early stages of postnatal development.Macrophages and their nuclei were irregular in shape.These macrophages were located beneath the cells of the organ of Corti,along the junction between Hensen's cells and Claudius'cells,and were visible in the apical,middle and basal cochlear turns.Starting at postnatal day 17,nuclei in some macrophages disappeared,leaving behind anucleated residual bodies.Macrophage degradation developed from basal to apical turns.The average length of macrophages at postnatal 1-2weeks was greater than that at postnatal 3-4weeks(P<0.05,t-test).Conclusion Macrophages are present in the organ of Corti at early stages of postnatal development.As the sensory epithelium matures,these cells undergo a development death.It is suggested that the degeneration of macrophages from the basal to apical turns may play a role in the development of cochlear sensory epithelium.