增高的間質液壓對纖維母細胞以及T細胞移動的影響

Abstract

許多發炎反應、類似發炎反應的腫瘤環境的病理環境中都伴隨著增高的間質液壓，然而間質液壓對於這些病理環境中細胞的行為表現的影響仍然是有待研究的。我們在這次的研究中藉由探討增高的間質液壓下細胞的移動能力來檢視細胞在高壓環境下的細胞的行為表現的改變。我們選擇了T淋巴細胞以及纖維母細胞當做我們的觀察對象，這兩者細胞在發炎環境中都扮演了重要的角色，前者是在發炎反應中進行免疫反應、對抗病原等等；後者則是在發炎環境中會透過合成細胞基質進行組織修復，然而過於活化的纖維母細胞同時又會造成發炎環境的纖維化影響等等。同時兩者移動的模式略有不同，前者屬於阿米巴式的移動模式，移動速度偏快；後者則是間葉細胞的移動模式，移動速度較慢。我們的實驗設計是將細胞培養在微流道裝置中，透過將針筒拉高的方式對裝置產生水壓，藉此來模擬生理環境中的間質液壓，藉由實時的顯微鏡拍攝記錄長時間的細胞移動狀態，進一步的計算移動速度，量化螢光染色、西方墨點法等等驗證我們的假說。我們目前發現在我們實驗中給予水壓範圍內，水壓會促進纖維母細胞移動速度，卻不會影響T淋巴球的移動速度。我們推測可能的分子機轉透過螢光染色與西方墨點法映證了水通道蛋白(Aquaporin-1)在水壓下部分調節細胞移動所扮演的角色－透過水壓促使水通道蛋白的表現量進而影響細胞移動，加速細胞在水壓狀態下的移動速度。另外進一步的數學分析纖維母細胞移動模式，我們發現了在水壓會促進纖維母細胞移動促發，同時生物實驗也證實在水壓下filamin表現量上升，filamin是一個控制移動促發的重要蛋白質。我們的研究突顯了水壓影響細胞移動的重要性並且在組織工程和腫瘤細胞學中都提供了一大進展。

Many inflammatory and inflammatory-mimic conditions such as solid malignant tumors are characterized by increased interstitial fluid pressure. However the role of the increased interstitial pressure in the improvement or deterioration of the pathological conditions remains unclear. In the present work, we investigated whether increased interstitial pressure affects the recruitment of cells to the diseased tissues by changing cell motility. Specifically we examined the migration speeds of T cells and fibroblasts, both respond to tissue inflammation with that one moves in amoeboid style and the other in mesenchymal mode. The cells were cultured in a microfluidic-based device and exposed to hydrostatic pressures similar to the interstitial pressures seen in inflammatory conditions. Time-lapsed live cell images were acquired to track the migration speeds of individual cells. Quantitative immunostaining and western blotting were employed to analyze changes of proteins expression associated with pressure exposure. Our results show that increased hydrostatic pressure enhanced the motility of fibroblasts but not T cells, which is at least in part mediated by the increased expression of aquaporin-1. Mathematical analysis of the migration pattern of fibroblasts revealed that increased hydrostatic pressure primarily enhanced initiation of migration, which was further supported by experimentally proving that increased hydrostatic pressure increased expression of filamin, a key protein in initiation of cell migration. Out findings highlight the importance of increased interstitial fluid pressure in regulation of cell motility and should shed light in the advancement of many biomedical fields ranging from tissue engineering to cancer biology.