同济大学高绍荣教授发表Stem Cells Transl Med文章

　　

      同济大学生命科学与技术学院高绍荣教授课题组在《Stem Cells Translational Medicine》杂志发表研究成果“Naïve Induced Pluripotent Stem Cells Generated From β-Thalassemia Fibroblasts Allow Efficient Gene Correction With CRISPR/Cas9”。
 
      β-地中海贫血是由于珠蛋白基因的缺失或点突变造成β-珠蛋白链合成减少或缺乏，从而导致血红蛋白四聚体α-链/非α-链之间失去平衡所引起的一种溶血性遗传病。患有重型β-地贫的患儿出生时正常，但数月后开始出现进行性溶血性贫血。未经输血治疗的患儿大多于5岁前死于严重贫血或严重感染性疾病。目前，该病没有有效的治疗方法。
 
      “Naïve态”概念的提出，使得人们对多能性的认识提高到了一个新的高度。与传统的“primed”状态相比，naïve状态的干细胞不仅具有更高的自我更新能力和多向分化潜能，并且其单细胞传代的易操作性显著提高了干细胞的扩增和复苏效率，更大大增加了基因操作的可行性，因而在再生医学及个体化临床治疗方向上具有更为广阔的应用前景。
 
      在这项研究里，研究人员成功建立了无外源基因整合的携带有TCTT四个碱基缺失的β-地中海贫血病人特异性naïve状态多能性干细胞，并通过CRISPR/Cas9基因打靶技术定点修复突变位点。同时，研究还发现naïve状态iPS的基因打靶修复效率较传统的primed状态iPS相比明显提高。因此，我们的研究表明，建立病人特异性的naïve状态的多能性干细胞为疾病模型的建立及将来的细胞治疗提供了一种更加可行，更加优越的细胞类型。
 
      高绍荣教授课题组的2013级博士生杨媛媛和江赐忠教授课题组的助理教授张小白为本文的共同第一作者，高绍荣教授与王译萱副教授为本文的共同通讯作者。本项目得到中国国家自然科学基金委，中国科技部973计划，上海市科学技术委员会，上海市教育委员会，同济大学青年优秀人才计划以及NSFC-广东联合基金的资助。
 
原文摘要：

Naïve Induced Pluripotent Stem Cells Generated From β-Thalassemia Fibroblasts Allow Efficient Gene Correction With CRISPR/Cas9

Conventional primed human embryonic stem cells and induced pluripotent stem cells (iPSCs) exhibit molecular and biological characteristics distinct from pluripotent stem cells in the naïve state. Although naïve pluripotent stem cells show much higher levels of self-renewal ability and multidifferentiation capacity, it is unknown whether naïve iPSCs can be generated directly from patient somatic cells and will be superior to primed iPSCs. In the present study, we used an established 5i/L/FA system to directly reprogram fibroblasts of a patient with β-thalassemia into transgene-free naïve iPSCs with molecular signatures of ground-state pluripotency. Furthermore, these naïve iPSCs can efficiently produce cross-species chimeras. Importantly, using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 nuclease genome editing system, these naïve iPSCs exhibit significantly improved gene-correction efficiencies compared with the corresponding primed iPSCs. Furthermore, human naïve iPSCs could be directly generated from noninvasively collected urinary cells, which are easily acquired and thus represent an excellent cell resource for further clinical trials. Therefore, our findings demonstrate the feasibility and superiority of using patient-specific iPSCs in the naïve state for disease modeling, gene editing, and future clinical therapy.