人類凝血調節素(TM)是細胞膜表面的一種醣蛋白，可藉和凝血蛋白酵素(thrombin)結合來調控體內促進凝血的生理機制。另外，近年亦有文獻指出TM具有其他生理功能，例如調節細胞骨架，進而調控細胞間結合與改變細胞形態等。皮膚之上皮組織中無TM表現的基部層(basal layer)，其細胞形態較呈正方體。相對地，位其上層具TM表現的刺狀層(spinous layer)，細胞形狀則較為扁平。是否TM的表現會加強與細胞骨架間的接合，使得細胞表現較強的張力，進而使細胞形態由正方體改變為較為扁平，即為本研究欲探討之焦點。
原子力顯微鏡(AFM)可取得活體細胞的高解析度影像，也可藉由力-距離曲線(force-distance curve)的擷取來評估細胞的力學性質。本研究便是使用AFM來觀察人類黑色素瘤細胞，在經過基因轉殖調控TM表現與否之後，於細胞形態及力學性質上的差異，進一步探討TM在細胞內所扮演的角色與作用機制。我們以TM negative的人類黑色素腫瘤細胞(vector cell)來模擬基部層的細胞，另外以基因轉殖的方式使同種細胞產生TM大量表現的效果(TM cell)來模擬刺狀層的細胞。依目前結果，TM cell之彈性模數為2646 ± 309 Pa (n = 6)，較vector cell之1687 ± 235 Pa (n = 6)來得高，更說明了TM的表現確實能夠使細胞內部張力改變進而影響其形態的論述。
此外，本研究嘗試利用AFM影像掃瞄之力量設定參數的差距，發展能夠更快速評估細胞彈性模數分佈的新概念(isoforce mapping)，期望以較短的量測時間完成活體細胞整體的彈性力學量測。經實際驗證後，目前此技術顯示能快速得到探針受力與細胞形變間的關係，唯數據分析與數學模型的修正上，仍有問題尚待克服。

Thrombomodulin (TM) is a glycoprotein distributed on cell membrane. TM can alter the coagulant activity of thrombin in terms of forming complex with thrombin. Recent studies have demonstrated other novel functions of TM. For example, TM could modulate the attachment of cytoskeleton, and then regulate cell-cell adhesion and cell morphology. Besides, the TM negative cells of basel layer at epidermis of skin tissue, exhibit a cubic shape, while the TM expressed cells of spinous layer show flat form. Thus, our hypothesis is that the expression of TM enhances the connection of cytoskelotons, results in stronger tension force, and then alters cell shape from cubic to flat form.
Atomic force microscopy (AFM) has high resolution to image living cells, and it could be operated in similarly physiology environment, and AFM could be used to evaluate mechanical properties of cells by using force-distance curve. In this study, we use AFM to investigate the effect of TM on regulating cell morphology and mechanical properties in human melanoma cell with and without TM expression after gene transfection. We choose TM negative human melanoma cell (A2058) to simulate basel layer cell, and use gene transfection to obtain TM over-expressed cell to simulate cell of spinous layer. From the preliminary result, we found that stiffness of cells transfected TM (TM cell) are higher than stiffness of TM negative cell (vector cell). The Young’s modulus of both are 2646 ± 309 Pa (n = 6) and 1687 ± 235 Pa (n = 6), respectively.
Furthermore, we also attempt to develop a new method to evaluate whole cell mechanical properties fast by means of difference of scan forces. From the preliminary result, this method could get the force on probe and the deformation of whole cell with high speed. But there are still some problems on data analyzing and mathematic model correcting.

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