腰椎管狹窄症（LSS）是老年人腰背痛的主要原因之一，黃韌帶肥厚（LFH）是LSS的主要病理機制。雖然關於黃韌帶( LF )的發病機制已有很多文獻，但LFH的確切病理機制仍然知之甚少。除了衰老外，機械應力刺激被認為是誘導LFH肥大的重要因素。
越來越多的研究集中在應用機械應力作為物理刺激來研究動態培養在不同類型細胞中的作用，例如心肌細胞的再生和血管壁細胞的修復。只有一項文獻表明，透過動態拉伸系統中的LF細胞培養可用於研究LFH的機制。在這些文獻中，大多數研究集中在傳統的二維（2D）培養上，此種培養條件對LF細胞的研究提供的信息很少，因此更加迫切地需要更多的生理相關培養環境。
在這裡，我們研究了機械應力對LF細胞的多維培養條件的影響，試圖部分地模擬LF細胞在人體內的運動。利用現有的商用動態培養系統及其二維（2D）平台，我們進一步開發了兩種類型的三維條件（2.5和3D），商用系統可以很容易地採用這種條件對LF細胞施加機械應力。發現在2D，2.5D和3D培養中對LF細胞的研究在72小時內呈現不同的細胞排列和細胞形態。
最後，我們成功地證明了LF細胞在我們的3D拉伸平台上與成纖維細胞具有高度的相似性，並且發現在傳統2D培養和3D培養中細胞排列和形態的差異，儘管使用3D拉伸平台仍存在一些不便。在未來，我們希望通過在更穩定的3D拉伸平台中培養LF細胞，我們將能夠進一步了解LFH的機制。

Lumbar spinal stenosis (LSS), is one of the most common causes of low back pain in the elderly, and ligamentum flavum hypertrophy (LFH) is the main pathomechanism of LSS. Although there have been many literatures on the pathogenesis of ligamentum flavum (LF), the exact pathological mechanism of LFH remains poorly understood. Besides aging, the mechanical stress stimulation is considered an important factor to induce the hypertrophy of LF.
More and more research focuses on applying mechanical stress to serve as a physical stimuli to study the effect of dynamic culture in different types of cells, such as regeneration of cardiomyocytes and repair of vascular wall cells. Only one study demonstrated that the LF cells culture on the dynamic stretching system could be utilized to study the mechanism of LFH. Among these literatures, most of studies focus on conventional two-dimensional (2D) culture, suggesting little information is provided on the study of LF cells and highlighting generation of more physiological relevant culture environment is desired.
Here, we investigated the effect of mechanical stress in multi-dimensional culture condition for LF cells, in attempt to partly mimic the motion of LF cells in human body. Taking advantage of the commercial dynamic culture system and its two-dimensional (2D) platform, we further developed two types of three-dimensional conditions (2.5 and 3D) that could be easily adopted by the commercial system to apply mechanical stress on LF cells. Investigation on the LF cells in 2D, 2.5D and 3D culture was found to present different cell alignment and cell morphology over the course of 72 h.
Finally, we successfully demonstrated that the LF cells have high degree of similarity to fibroblasts on our 3D stretching platform and found difference in cell alignment and morphology in conventional 2D culture and 3D culture, although there was some inconvenience of using the 3D stretching platform. In the future, we hope that we will be able to further understand the mechanism of LFH by cultivating the LF cells in a more stable 3D stretching platform.

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