利用幹細胞發展培養再生組織或器官來進行醫療研究，為醫療發展的一大趨勢，但是由於免疫系統對外來幹細胞的排斥，以及自體幹細胞的取得與培養相對的並不容易，因此就目前為止，取得不會引起免疫排斥的幹細胞是目前幹細胞醫療的瓶頸，但是如果能利用病人本身的體細胞做為材料，進行胞外實驗使其回復到前驅細胞的時期，再依所需而誘導其轉分化，對於幹細胞的醫療研究將會是一大突破。在我們的研究中，選擇兩個幹細胞的轉錄因子Nanog與Oct3為標的，利用已建立好的Retrovirus系統，來建立大量表現標的基因的Sol8穩定細胞，進而利用此穩定細胞株來分析幹細胞因子對於肌肉細胞分化過程的影響。在我們的實驗中發現，由形態來看，當同時表現兩個幹細胞因子Nanog與Oct3的Sol8穩定細胞株時，會抑制肌肉細胞走向終末分化，且在利用RT-PCR及Western blot分析中得到肌肉細胞中的肌肉特化因子MyoD、Myogenin同時會受到抑制，另外我們在同時表現Nanog與Oct3的穩定細胞株中處理β-mercaptoethanol，發現當細胞中添加的量越高時，myf5的表現量相對的受到抑制的現象。在我們的實驗中，我們發現了當肌肉細胞中同時表現幹細胞因子Nanog與Oct3時，會促使肌肉細胞不會走向終末分化，至於要使肌肉細胞回復到前驅細胞且帶有pluripotency的能力，將需 要再進一步的研究來達成這遠程的目標。 The potential of cell mediated tissue regeneration is hampered by both immune rejections of engrafted allogenic ES cells and the difficulties of isolating and propagating autologous stem cells. However, if the somatic cells can be induced to transdifferentiate into precursors of target cell types in vitro, cell mediated tissue regeneration will be more applicable. In this study, we introduced two ES cell-specific transcription factors, Nanog and Oct3, into sol8 myoblast using retrovirus system and examined the effects on differentiation stage of the stable clones. Over expressing Nanog and Oct3 simultaneously, but not independently, impaired the terminal differentiation of Sol8 myoblasts. Furthermore, the expression of myogenic regulator factors (MRFs), MyoD and Myogenin, is abolished in Sol8-Nanog/Oct3 cells. In addition, the slightly repression of Myf5 expression could be further diminished after β-mercaptoethanol treatment. Our data suggest that although over expressing Nanog and Oct3 in myoblasts can surpress myogenic differentiation, whether those cells acquired pluripotency still needs to be further investigated.
