Toward a better understanding of the cellular basis for cerebrospinal fluid shunt obstruction: report on the construction of a bank of explanted hydrocephalus devices
Toward a better understanding of the cellular basis for cerebrospinal fluid shunt obstruction: report on the construction of a bank of explanted hydrocephalus devices
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DOI：
10.3171/2016.2.peds15531
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发表时间：
2016-08-01
影响因子：
1.9
通讯作者：
Shain, William
中科院分区：
文献类型：
--
作者：
Hanak, Brian W.;Ross, Emily F.;Shain, William
目的细胞和/或组织造成的分流阻塞是分流失败的最常见原因。仅脑室导管阻塞就占儿科患者分流失败的50%以上。作者试图系统地收集从西雅图儿童医院的脑室导管，重点是阐明阻塞的细胞机制。每周将样品转移至缓冲溶液中，并在4 ℃下储存。在获得使用同意后，使用星形胶质细胞（胶质细胞酸性蛋白）、小胶质细胞（离子化钙结合衔接分子1）和脉络丛（甲状腺素运载蛋白）的细胞特异性标记物结合核染色（Hoechst）标记导管。将导管安装在定制的聚碳酸酯成像室中。使用三维、多光谱、旋转盘共聚焦显微镜对导管脑脊液入口孔进行成像（10倍物镜，499.2 μ m厚z堆叠，2.4 μ m步长，Olympus IX 81倒置显微镜，配有电动载物台和电荷耦合器件相机）。值报告为平均值+/-平均值的标准误差，并使用双尾Mann-Whitney U检验进行比较。结果：1）星形胶质细胞和小胶质细胞是直接与导管表面结合的主要细胞类型，2）细胞与导管的结合是普遍存在的，即使没有明显的肉眼可见的组织;和3）当导管已经暴露于Bugbee线电烙术时，免疫组织化学技术的效用有限。在排除7根暴露于Bugbee钢丝烧灼的导管、3根固定不良的导管和2根显示明显自体荧光的导管后，对24根导管进行了统计分析。该分析显示，具有小胶质细胞主导的细胞反应的导管倾向于植入较短的持续时间（24.7 +/- 6.7天）比星形胶质细胞占主导地位的反应（1 183 +/- 642天;结论：脑室导管闭塞仍然是儿科人群分流发病率的重要来源，并且考虑到它们与导管表面紧密结合的能力，星形胶质细胞和小胶质细胞似乎对这种病理生理学是至关重要的。小胶质细胞往往是植入少于2个月的导管上的主要细胞类型，而星形胶质细胞往往是植入较长时间的导管上最普遍的细胞类型，并且被注意到作为室管膜细胞和脉络丛的次级附着的界面。
OBJECTIVE Shunt obstruction by cells and/or tissue is the most common cause of shunt failure. Ventricular catheter obstruction alone accounts for more than 50% of shunt failures in pediatric patients. The authors sought to systematically collect explanted ventricular catheters from the Seattle Children's Hospital with a focus on elucidating the cellular mechanisms underlying obstruction.METHODS In the operating room, explanted hardware was placed in 4% paraformaldehyde. Weekly, samples were transferred to buffer solution and stored at 4 degrees C. After consent was obtained for their use, catheters were labeled using cell-specific markers for astrocytes (glial fibrillary acidic protein), microglia (ionized calcium-binding adapter molecule 1), and choroid plexus (transthyretin) in conjunction with a nuclear stain (Hoechst). Catheters were mounted in custom polycarbonate imaging chambers. Three-dimensional, multispectral, spinning-disk confocal microscopy was used to image catheter cerebrospinal fluid-intake holes (10x objective, 499.2-mu m-thick z-stack, 2.4-mu m step size, Olympus IX81 inverted microscope with motorized stage and charge-coupled device camera). Values are reported as the mean +/- standard error of the mean and were compared using a 2-tailed Mann-Whitney U-test. Significance was defined at p < 0.05.RESULTS Thirty-six ventricular catheters have been imaged to date, resulting in the following observations: 1) Astrocytes and microglia are the dominant cell types bound directly to catheter surfaces; 2) cellular binding to catheters is ubiquitous even if no grossly visible tissue is apparent; and 3) immunohistochemical techniques are of limited utility when a catheter has been exposed to Bugbee wire electrocautery. Statistical analysis of 24 catheters was performed, after excluding 7 catheters exposed to Bugbee wire cautery, 3 that were poorly fixed, and 2 that demonstrated pronounced autofluorescence. This analysis revealed that catheters with a microglia-dominant cellular response tended to be implanted for shorter durations (24.7 +/- 6.7 days) than those with an astrocyte-dominant response (1183 +/- 642 days; p = 0.027).CONCLUSIONS Ventricular catheter occlusion remains a significant source of shunt morbidity in the pediatric population, and given their ability to intimately associate with catheter surfaces, astrocytes and microglia appear to be critical to this pathophysiology. Microglia tend to be the dominant cell type on catheters implanted for less than 2 months, while astrocytes tend to be the most prevalent cell type on catheters implanted for longer time courses and are noted to serve as an interface for the secondary attachment of ependymal cells and choroid plexus.