目前已有許多研究證實給予幹細胞特定的化學生長因子能誘導幹細胞朝向特定分化之路徑前進，而給予幹細胞不同的物理刺激模式也確實會影響幹細胞基因的表現、蛋白質的分泌及細胞的生長、遷移、增殖、分化等細胞行為。本文主旨為設計製作可對細胞施加流體剪應力刺激之生物反應器。其作動原理為利用馬達轉動並帶動圓錐與平板培養室間之培養液旋轉，而旋轉的培養液會對平板培養室上之細胞進行剪應力刺激，並藉由扭力量測裝置的設計能即時定量監控作用於平板上之剪應力大小與誤差。 經過細胞相容性測試後，本研究以此圓錐平板型生物反應器進行流體剪應力對幹細胞分化影響之研究。嘗試利用1-甲基-3-異丁基黃嘌呤 (1-methyl-3-isobutylxanthine, IBMX) 誘導人類胎盤幹細胞 (Placenta Derived Multipotent Cells, PDMCs) 分化為神經細胞，並於投藥過程中利用自製生物反應器施予1、4、8 dyn/cm2三種不同強度之流場剪應力刺激10分鐘，觀察刺激後2小時與72小時對PDMCs分化之影響。實驗結果顯示IBMX若配合較大之流體剪應力進行PDMCs誘導分化，能增進PDMCs分化為神經細胞之趨勢。Many research results have demonstrated that stem cells can differentiate into specialized cells by chemical induction. Physical stimuli have also been confirmed to be able to trigger specific gene expressions, induce secretion of proteins and modulate cell behaviors such as growth, migration, proliferation and differentiation. In this study we designed a cone-plate bioreactor which can produce quantified fluid shear stress. By rotating the cone, the bioreactor drives the culture medium to flow in a circular way, which generates virtually uniform azimuthal shear stress that can be applied to the cultured cells on the plate. In order to perform a real time monitoring over the magnitudes of shear stress, a torque sensor was installed to measure the torque caused by the shear stress on the plate. After biocompatibility tests, the Placenta Derived Multipotent Cells (PDMCs) were cultured in the bioreactor. The PDMCs were then induced toward neuronal differentiation by applying both the chemical and physical stimulation simultaneously. We applied 1-methyl-3-isobutylxanthine (IBMX) as the chemical agent and investigated the effectiveness of the shear stress on cell differentiation. The application of shear stress along without IBMX addition showed no cell differentiation. However, the PDMCs differentiation initiated by the IBMX were enhanced by simultaneously applying the stress.
