Ling E A, Kaur L C, Yick T Y, Wong W C
Department of Anatomy, Faculty of Medicine, National University of Singapore, Kent Ridge.
Anat Embryol (Berl). 1990;182(5):481-6. doi: 10.1007/BF00178913.
The present study described the labelling of amoeboid microglial cells in the postnatal rat brain with OX-42, an antibody that recognizes type 3 complement receptors CR3 in mononuclear phagocytes. Of the diverse morphological forms of amoeboid microglia present in the corpus callosum in early postnatal (2-5 days) rats, cells with a round regular outline, or showing short stout processes, were the most intensely stained. When traced from the main cell colony into the borderline zone with the cortex, the immunoreactivity of amoeboid microglia that assumed a ramified form was drastically reduced. Examination of materials from the late postnatal (8-12 days) age group showed that the majority of the OX-42 positive cells in the corpus callosum became oval, elongated and ramified. Immunoelectron microscopy confirmed the above observations, and also showed that the immunoreactivity in the round amoeboid microglia was localized in their plasma membrane, surface projections and invaginations, as well as in some of the subsurface vacuoles. The immunoreactivity was reduced in the oval cells, and diminished in the elongated or ramified form. It is proposed that the presence of CR3 membrane receptors in amoeboid microglial cells is related to their active role in endocytosis. These, however, diminish with the growth of the brain.
本研究描述了用OX - 42对新生大鼠脑内阿米巴样小胶质细胞进行标记的情况，OX - 42是一种识别单核吞噬细胞中3型补体受体CR3的抗体。在出生后早期（2 - 5天）大鼠胼胝体中存在的多种形态的阿米巴样小胶质细胞中，轮廓规则圆形或有短粗突起的细胞染色最为强烈。当从主要细胞群体追踪到与皮质的交界区域时，呈分支状的阿米巴样小胶质细胞的免疫反应性急剧降低。对出生后晚期（8 - 12天）年龄组材料的检查表明，胼胝体中大多数OX - 42阳性细胞变成椭圆形、细长形并呈分支状。免疫电子显微镜证实了上述观察结果，还表明圆形阿米巴样小胶质细胞中的免疫反应性定位于其质膜、表面突起和内陷以及一些表面下空泡中。椭圆形细胞中的免疫反应性降低，而细长形或分支状细胞中的免疫反应性减弱。有人提出，阿米巴样小胶质细胞中CR3膜受体的存在与其在内吞作用中的积极作用有关。然而，随着脑的生长，这些作用会减弱。
