幹細胞  中風者福音

老鼠實驗顯示幹細胞可存活於受損部位為中風者帶來希望

【本報綜合報導】胎兒腦部的幹細胞有朝一日可望用來取代因中風受損的腦細胞。這些幹細胞也為治療破壞性大的腦部疾病和脊椎傷害帶來希望。   

加州史丹福大學做的老鼠實驗顯示，把人類胎兒腦部幹細胞植入老鼠腦部後，這些幹細胞會自動前往中風受損的部位，並且存活。這是一項重要發現，因為中風造成的損害通常也會殺死鄰近的細胞。 

主持研究的神經外科醫師史坦柏格說：「這是首次有研究顯示，人類幹細胞可以在中風的環境下生存、移動位置、和長成不同的組織和細胞。」 

研究人員使用的細胞取自數年前墮胎的胎兒 然後在實驗室培養。史坦柏格說: 「這些腦部幹細胞不是胚胎的幹細胞，所以應該沒有爭議性。」 

幹細胞是指尚未發育成熟的細胞，可以長成各種組細胞和組織。幹細胞的來源不一，從骨髓、胎兒組織到胚胎都有。但是從只有數日大的人類胚胎萃取幹細胞會引起爭議。 

研究人員對人為引起中風的老鼠試驗胎兒腦部幹細胞的治療效果 發現這些細胞可以在老鼠體內活一個月 同時會自己找到路前往中風部位。史坦柏格說:「這些細胞是聰明的細胞。」 

他說:「這些細胞為什麼會移往中風部位?我們的初步證據顯示 與中風部位釋出的化學物質和趨化激素(chemokines)有關。趨化激素是細胞釋出的化學訊號亦即一種求援的分子訊號。 

研究小組正在評估，看這些細胞對中風老鼠的復原有無幫助。史坦柏格說，他們目前給老鼠服用抗排斥藥 但還不確定需不需要使用這種藥防止身體對於這些外來細胞的排斥作用。

研究報告刊載在美國科學會公報。

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