Pluripotency of Amniotic Fluid-Derived Stem Cells

人类多能干细胞(HPSCs)对于再生疗法的发展至关重要，特别是在自体、特化细胞不能获得足够数量的情况下。尽管前景光明，但多能胚胎干细胞(ES)也有一些公认的缺陷。这些问题包括致瘤性和组织相容性匹配的困难。其他类别的hPSC可以克服这些限制。在机构范围的计划公告中，羊水被特别指出为hPSCs的潜在非胚胎来源。我们最近描述了克隆的人类AFS细胞系，并证明它们能够产生包括三个胚胎生殖层的每一个代表的细胞系。其他人描述了使用特定的遗传因素将体细胞重新编程为类似ES的状态，称为诱导多能干细胞(IPS)。我们假设AFS细胞代表了比ES和iPS细胞更高级的发育阶段，同时仍然保持了高度的多能性。特别是，在初步数据的支持下，我们预计AFS细胞在有利于ITS和iPS细胞形成肿瘤的条件下不会产生畸胎瘤，因此，对AFS和ES或iPS细胞表达的基因进行关键比较将导致对多能性必不可少的功能以及与畸胎瘤形成相关的功能的重要洞察。在这种比较中，一个令人困惑的因素是，来自不同人类的细胞系在基因上是不同的。为了准确地关注与发育阶段相对应的差异，我们建议比较来自相同个体的匹配的AFS和iPS细胞对。这将通过使用定义的因子将AFS单元重新编程到更原始的ES类状态来实现。(我们指的是这种重新编程的细胞iPS-AFS细胞)。在我们最初的R01申请的这个修订版中，我们打算从大学之外招聘两名新员工。一名新的初级博士后研究员和一名新的初级技术员。

Human pluripotent stem cells (hPSCs) win be crucial for the development of regenerative therapies, especially when autologous, specialized cells cannot be obtained in sufficient quantity. Despite great .promise, pluripotent embryonic stem (ES) cells have some recognized drawbacks. These include tumorigenicity and difficulty of histocompatibility matching. Other classes of hPSCs may overcome these limitations. In the agency-wide Program Announcement, amniotic fluid is noted specifically as a potential non-embryonic source for hPSCs. We recently described clonal human AFS cell lines and demonstrated that they are able to give rise to cell lineages that include representatives of each of the three embryonic germ layers. Others have described the use of defined genetic factors to reprogram somatic cells to an ES-like state, termed induced pluripotent stem (iPS) cells. We hypothesize that AFS cells represent a developmentally more advanced stage than ES and iPS cells, while nevertheless retaining a high degree of pluripotency. In particular, with support from preliminary data, we anticipate that AFS cells will not give rise to teratomas under conditions conducive to tumor formation by its and iPS cells, Therefore, critical comparison of genes expressed by AFS and ES or iPS cells should lead to significant insights into functions essential for pluripotency and also into those associated with teratoma formation. A confounding factor in such comparisons is that cell lines derived from different human beings are genetically diverse. In order to focus precisely on differences · corresponding to developmental stage, we propose to compare matched pairs of AFS and iPS cells from the same individuals. This will be achieved by using defined factors to reprogram AFS cells to the more primitive ES-like state. (We refer to such reprogrammed cells iPS-AFS cells). In this revised version of our original R01 application we intend to hire two new employees from outside the University. A new junior post-doctoral fellow and a new junior technician.