Ennas M G, Cocchia D, Silvetti E, Sogos V, Riva A, Torelli S, Gremo F
Department of Cytomorphology, School of Medicine, Cagliari, Italy.
J Neurosci Res. 1992 Jul;32(3):424-36. doi: 10.1002/jnr.490320314.
During the past few years, evidence has accumulated that interaction with peripheral immune cells as well as immunoregulatory functions in the central nervous system (CNS) can be played by several types of brain resident cells. Since very little information is available in man, however, we investigated the presence of markers so far considered typical of immunocompetent cells in in vitro cultures of human fetal brain. Immunocytochemistry at the light, scanning, and transmission electron microscopic levels revealed positivity for a very restricted range of macrophage antigens in astrocytes, which, however, were incapable of phagocytosis. In particular, expression of the major histocompatibility complex-class II antigen HLA-DR was observed in the cytoplasm and on the cell surface of GFA-P+ astrocytes and increased with time in culture and cell passages. Among the T-lymphocyte markers tested, Thy.1 and CD4 were positive. Both neurons and astrocytes carried Thy.1 from early cell passages. Noteworthy was the presence of CD4, which serves as the receptor for AIDS virus, in neurons from the first 2 weeks, whereas astrocytes became positive after only 4-6 weeks. Even if most staining was in the cytoplasm, some was exposed on cell surface. Astrocytes were found positive for the B-lymphocyte marker CD21, the cellular receptor for Epstein-Barr virus, whereas CD24 was detected in both neurons and astrocytes. Both antigens are related to B-cell proliferation. Results are in favour of the hypothesis of human brain cells being actively involved in CNS immunological events.
在过去几年中，越来越多的证据表明，几种脑内驻留细胞可与外周免疫细胞相互作用，并在中枢神经系统（CNS）中发挥免疫调节功能。然而，由于人类方面的信息非常有限，我们研究了迄今为止被认为是免疫活性细胞典型标志物在人胎脑体外培养物中的存在情况。光镜、扫描电镜和透射电镜水平的免疫细胞化学显示，星形胶质细胞中巨噬细胞抗原的阳性范围非常有限，然而，这些星形胶质细胞无吞噬能力。特别是，在GFA-P+星形胶质细胞的细胞质和细胞表面观察到主要组织相容性复合体II类抗原HLA-DR的表达，并且随着培养时间和细胞传代而增加。在所测试的T淋巴细胞标志物中，Thy.1和CD4呈阳性。神经元和星形胶质细胞从早期细胞传代开始就携带Thy.1。值得注意的是，作为艾滋病病毒受体的CD4在前两周的神经元中就存在，而星形胶质细胞仅在4-6周后才呈阳性。即使大多数染色在细胞质中，但也有一些暴露在细胞表面。发现星形胶质细胞对B淋巴细胞标志物CD21呈阳性，CD21是爱泼斯坦-巴尔病毒的细胞受体，而CD24在神经元和星形胶质细胞中均被检测到。这两种抗原都与B细胞增殖有关。结果支持人脑细胞积极参与中枢神经系统免疫事件这一假说。
