Neufeld A H
Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St Louis, MO 63110, USA.
Arch Ophthalmol. 1999 Aug;117(8):1050-6. doi: 10.1001/archopht.117.8.1050.
Microglia, the macrophages and immune surveillance cells of the central nervous system, are quiescent normally but become activated in injured neural tissue. We have determined the distribution and potential participation of microglia in glaucomatous optic nerve degeneration.
Microglia were localized by immunohistochemistry on paraffin sections of age-matched normal and glaucomatous human eyes obtained within 24 hours after death. Monoclonal and polyclonal antibodies that recognize specific epitopes on microglia and other cell types were localized by immunoperoxidase and immunofluorescence.
Stellate cells with thin, ramified processes, positive for HLA-DR and CD45 but negative for glial fibrillary acid protein, were identified as quiescent microglia. These cells were found throughout the normal optic nerve head in the walls of large blood vessels and surrounding capillaries in glial columns and cribriform plates. In glaucomatous eyes with moderate and severe optic nerve head damage, microglia were present as clusters of large ameboid, activated cells in the compressed lamina cribrosa and as formations of concentric circles surrounding blood vessels. In the parapapillary chorioretinal region of glaucomatous optic nerve heads, large, activated microglia were present as single cells or clusters on the termination of the Bruch's membrane. In addition, along the optic nerve/choriocapillaris-scleral interface, activated microglia appeared to form linear arrays near the choriocapillaris vessels. These cells were parenchymal and not in close association with the vasculature.
In glaucoma, microglia in the optic nerve head become activated and redistributed. Enlarged, activated microglia appear in the parapapillary chorioretinal region, perhaps due to migration from the disorganized prelaminar and laminar tissue. Strategically positioned microglia may also serve a neuroprotective function in relation to a damaged blood-retinal barrier. The activity of microglia in the parapapillary chorioretinal region in glaucoma may be responsible for some of the biomicroscopic and histological changes that are associated with parapapillary chorioretinal atrophy.
小胶质细胞是中枢神经系统的巨噬细胞和免疫监视细胞，通常处于静止状态，但在受损神经组织中会被激活。我们已经确定了小胶质细胞在青光眼性视神经变性中的分布及可能的参与情况。
通过免疫组织化学方法，在死后24小时内获取的年龄匹配的正常人和青光眼患者人眼石蜡切片上定位小胶质细胞。使用识别小胶质细胞和其他细胞类型上特定表位的单克隆抗体和多克隆抗体，通过免疫过氧化物酶和免疫荧光进行定位。
具有细长分支突起、HLA-DR和CD45呈阳性但胶质纤维酸性蛋白呈阴性的星状细胞被鉴定为静止小胶质细胞。这些细胞见于整个正常视神经乳头的大血管壁、胶质柱和筛板中的毛细血管周围。在中度和重度视神经乳头损伤的青光眼眼中，小胶质细胞以大的阿米巴样激活细胞簇的形式存在于受压的筛板中，并以围绕血管的同心圆形式存在。在青光眼性视神经乳头的视乳头旁脉络膜视网膜区域，大的激活小胶质细胞以单个细胞或细胞簇的形式存在于布鲁赫膜的末端。此外，沿着视神经/脉络膜毛细血管-巩膜界面，激活的小胶质细胞似乎在脉络膜毛细血管血管附近形成线性排列。这些细胞是实质细胞，与脉管系统没有紧密联系。
在青光眼中，视神经乳头的小胶质细胞被激活并重新分布。扩大的、激活的小胶质细胞出现在视乳头旁脉络膜视网膜区域，可能是由于从紊乱的板层前和板层组织迁移而来。处于战略位置的小胶质细胞也可能在受损的血视网膜屏障方面发挥神经保护作用。青光眼中视乳头旁脉络膜视网膜区域小胶质细胞的活性可能是与视乳头旁脉络膜视网膜萎缩相关的一些生物显微镜和组织学变化的原因。
