Name: reprogramming mature cells into stem cells
Uploaded: 2019-03-11T09:21:22.000Z
Duration: 1 min 13 s
Channel: JoVE

被诱导的多能干细胞iPSC
 
 是成熟的分化细胞 例如皮肤细胞
 
 其在实验室中重编程的细胞
 
 为与未分化的胚胎干细胞相似
 
 也就是说 它们会分裂并且是多能的
 
 能够在体内产生任何细胞类型
 
 例如 可用于替换受损视网膜组织的
 
 视网膜细胞
 
 为了产生iPSC
 
 可从患者体内取出成熟细胞
 
 如皮肤成纤维细胞，并进行培养
 
 然后 通常转录因子的基因
 
 通过病毒载体递送到细胞核中
 
 在那里它们被整合到基因组中
 
 转录因子然后打开
 
 由胚胎干细胞表达的基因
 
 这样能将他们分散
 
 并使他们处于多能状态
 
 现在 细胞可以分裂 并且理想情况下
 
 可倒入到培养物中产生特定的细胞类型
 
 然后可以将新细胞
 
 移植回患者体内 以最小的排斥风险
 
 治疗损伤或疾病
 
 因为它们来自患者自身的细胞

Hamazaki、Takashi、Nihal El Rouby、Natalie C. Fredette、Katherine E. Santostefano 和 Naohiro Terada。"简明回顾:精准医学时代的诱导多能干细胞研究。"干细胞（俄亥俄州代顿）35，第 3 期（2017 年 3 月）:545-50。[<a href="https://doi.org/10.1002/stem.2570" target="__blank">来源</a>]。

诱导多能干细胞

Induced Pluripotent Stem Cells

干细胞是未分化的细胞，分裂并产生不同类型的细胞。通常，分化成特定细胞类型的细胞是有丝分裂后的，也就是说，它们不再分裂。然而，科学家们已经找到了一种方法来重新编程这些成熟细胞，使它们“去分化”并恢复到未分化、增殖状态。这些细胞也是像胚胎干细胞一样的多能干细胞，能够产生所有类型的细胞，因此被称为诱导多能干细胞（IPSC）。

iPSCs在医学上具有潜在的价值，因为患者需要特定的细胞类型，例如，由于黄斑变性而导致视网膜受损的患者可以接受所需细胞的移植，这些细胞是由自身体内的另一种细胞类型产生的。这被称为自体移植，它降低了在个体间移植组织时发生移植排斥反应的风险。
 
<h4>过程</h4>
 
为了制造iPSCs，成熟细胞如皮肤成纤维细胞或人的血细胞在培养中生长。然后，使用病毒载体将多个转录因子的基因传递到细胞中，并使用细胞机器表达转录因子蛋白。转录因子随后启动许多由胚胎干细胞表达的其它基因，使细胞回到未分化、增殖和多能状态。
 
目前仍在研究iPSCs是否真的等同于胚胎干细胞，但它们看起来很相似，可以从身体的所有三个生殖层产生细胞。与其它类型的干细胞一样，科学家正在学习如何有效地促进特定细胞类型与iPSCs的分化，以便能够产生足够数量的所需细胞类型。
 
<h4>早期临床试验</h4>
 
第一个临床试验将来自iPSCs的视网膜细胞移植到年龄相关性黄斑变性患者中。自那以后，iPSC的几个临床试验已经被批准用于治疗帕金森病、心脏病和脊髓损伤。从病人身上提取并转化为 iPSCs的细胞也被用来在实验室研究他们的疾病。一般来说, iPSCs为科学研究提供了另一种干细胞来源。

干细胞是能够分裂并产生不同类型细胞的未分化细胞。通常情况下，已分化为特定细胞类型的细胞……

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reprogramming mature cells into stem cells

Reprogramming mature cells into stem cells lets scientists turn specialized cells back into an unspecialized state. These cells are called induced pluripotent stem cells, or iPSCs. Like embryonic stem cells, iPSCs are pluripotent, which means they can form all cell types.

To make iPSCs, researchers start with mature cells such as skin fibroblasts or blood cells. The cells are grown in culture, and genes for several transcription factors are delivered with a viral vector. The cells then make those transcription factor proteins, which switch on other genes that are active in embryonic stem cells and return the cells to a proliferative, undifferentiated, and pluripotent state.

iPSCs may be useful in medicine because they can come from a patient’s own body. For example, cells needed to repair a damaged retina in age-related macular degeneration could be made from that same patient’s cells. This autologous transplantation lowers the risk of transplant rejection that can happen when tissue is moved between different people.

Scientists are still studying whether iPSCs are truly equivalent to embryonic stem cells, but they appear to be similar and can produce cells from all three germ layers. Researchers are also working on ways to direct iPSCs to become specific cell types in efficient amounts. Early clinical trials have used iPSC-derived retinal cells for macular degeneration, and other trials have been approved for Parkinson’s disease, heart disease, and spinal cord injury. Patient cells turned into iPSCs are also helping scientists study disease in the lab.

Reprogramming Mature Cells into Stem Cells

reprogramming-mature-cells-into-stem-cells

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key terms and concepts

Learn how mature cells are reprogrammed into induced pluripotent stem cells, why iPSCs matter for transplants, and how they are used in research and clinical trials.

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Reprogramming Mature Cells into Stem Cells

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