Hoare Mary-Jo, Grierson Ian, Brotchie Daniel, Pollock Natalie, Cracknell Kathy, Clark Abbot F
Department of Clinical Science, Unit of Ophthalmology, University of Liverpool, Liverpool, UK.
Invest Ophthalmol Vis Sci. 2009 Mar;50(3):1255-63. doi: 10.1167/iovs.08-2706. Epub 2008 Oct 24.
A percentage of trabecular meshwork (TM) cells in tissue and organ culture have been shown to contain cross-linked actin networks (CLANs) when exposed to dexamethasone, as have TM cultures derived from glaucomatous individuals. The purpose of this study was to determine whether CLANs exist within TM cells in situ in tissue unmanipulated by culturing, thereby eliminating the possibility that CLANs are artifacts of culture conditions, and to determine their numbers and dimensions in normal and glaucoma TM cells.
Twelve human donor eyes (five normal and seven with glaucoma) provided the TM tissue. Each eye was dissected, and the TM tissue was exposed either by microdissection (qualitative studies) or cryo-sectioning (quantitative analysis). The actin cytoskeleton was visualized using a high-affinity probe and viewed using confocal microscopy.
Qualitative examination of the microdissected tissue revealed that CLANs and CLAN-like structures were a common finding in the TM cells in every specimen, irrespective of whether they were from normal or glaucomatous eyes. CLAN size and phenotype were variable, with the same variations occurring in both normal and glaucomatous eyes. Quantitative analysis showed that there were more CLANs in glaucoma TM specimens than normal TM specimens, but this difference was not statistically significant. The mean number of CLANs/TM cell in our glaucoma tissue was estimated to be 1.03, while in the elderly normal controls it was 0.67.
This study showed for the first time that CLANs exist in cells of TM tissues from both normal and glaucomatous eyes that have not been manipulated by either tissue or organ culture procedures. It also provides quantitative data on CLAN prevalence in organized TM tissue, which indicates that CLANs are far more common than predicted (even from tissue culture) and there may be one in every cell in the glaucomatous TM in situ.
已证明在组织和器官培养中，一定比例的小梁网（TM）细胞在暴露于地塞米松时会含有交联肌动蛋白网络（CLANs），来自青光眼患者的TM培养物也是如此。本研究的目的是确定在未经培养操作的组织中原位TM细胞内是否存在CLANs，从而排除CLANs是培养条件造成的假象的可能性，并确定正常和青光眼TM细胞中CLANs的数量和尺寸。
12只人类供体眼（5只正常眼和7只青光眼眼）提供了TM组织。每只眼睛进行解剖，TM组织通过显微切割（定性研究）或冷冻切片（定量分析）进行暴露。使用高亲和力探针使肌动蛋白细胞骨架可视化，并通过共聚焦显微镜观察。
对显微切割组织的定性检查显示，CLANs和CLAN样结构在每个标本的TM细胞中都是常见发现，无论它们来自正常眼还是青光眼眼。CLAN的大小和表型各不相同，正常眼和青光眼眼中都出现了相同的变化。定量分析表明，青光眼TM标本中的CLANs比正常TM标本中的多，但这种差异无统计学意义。我们青光眼组织中每个TM细胞的CLANs平均数估计为1.03，而老年正常对照中为0.67。
本研究首次表明，在未经过组织或器官培养程序处理的正常和青光眼眼的TM组织细胞中存在CLANs。它还提供了有组织的TM组织中CLANs患病率的定量数据，这表明CLANs比预期的更为常见（即使是从组织培养中得出的预期），并且在原位青光眼TM中每个细胞中可能都有一个CLANs。
