体细胞或成人干细胞,如胚胎干细胞,能够自我更新,但反映受限的分化潜能。尽管如此,这些细胞是稳态过程的关键因素,而且在组织修复中发挥重要的作用。通过学习和操作此单元格人口,科学家也许能够开发新的再生疗法,对伤害和疾病。
这个视频第一次定义成体干细胞,然后探讨了这些细胞在组织再生中的作用。描述一种协议,隔离肌卫星细胞并使用它们来修复肌肉损伤小鼠模型的肌营养不良症被强调了这一点。最后,我们讨论利用成体干细胞的特定组织再生研究。
成体干细胞发挥重要的作用,在维护和修理的广泛的组织。这些干细胞,像其父胚胎干细胞,有能力几乎是无限量的自我更新。然而,不像胚胎干细胞,可以分化成多种细胞类型,成体干细胞出现以后的发展,和他们的命运被限制为特定的器官的细胞。
这个视频将涵盖组织再生的原理,科学家研究的体细胞作用如何在组织中的干细胞修复以下损伤,和一些应用程序使用体细胞干细胞诱导组织再生。
让我们开始讨论背后组织再生的原则后伤害或损害。成体干细胞已在几个组织,包括大脑、 骨髓、 骨骼肌、 心、 肝、、 肠。
一般来说,这种可再生的干细胞来源首先区分进命运限制祖细胞前最终将崛起给专门功能的细胞。一个经典的例子是称为造血的日常生理过程。在此过程中,成体干细胞发现骨髓中的血液和免疫系统祖细胞,进一步分化细胞的各自的制度。
从组织再生的角度来看,成体干细胞在骨骼肌中找到已去玩一个角色在组织修复。当肌肉损坏时,这些细胞被招募到损伤的部位和区分以取代受损的细胞。
成体干细胞怎么知道现在是时候去上班?当细胞被破坏时,它们释放可溶性的趋化因子,趋化因子,招募成体干细胞对损伤的部位等。这些细胞可以分化成目标组织细胞类型。除了提供新的细胞,干细胞移植体细胞可以诱导局部的变化,促进伤口愈合的新血管的生成。
内源性成体干细胞的再生能力可能不总是足以修复患病和受损组织。因此,科学家们正在调查如何交付的成体干细胞的外源池可以用于治疗这种疾病。
既然你了解组织再生的生物学,让我们看看如何科学家可以分离成体干细胞和管理它们诱导组织修复的榜样。使用下面的方法,科学家们展示肌肉干细胞,称为卫星细胞,在后损伤的组织再生的援助。
第一,骨骼肌肉是从捐助鼠标解剖和帮助下游离酶,例如胶原酶消化。下一步,卫星细胞是孤立的和一个的方式做到这一点是通过孵化这些细胞与绑定到磁珠,然后纯化在磁选柱的抗体。经过纯化,卫星细胞在培养基中培养,后来分化为肌源性祖细胞的分化培养基中添加。
在此期间,收件人的鼠标被备肌内注射一种毒素导致的肌肉无力或肌营养不良症。准备好肌源性祖细胞然后注入营养不良的小鼠骨骼肌的影响。最终,成功整合和分化的体细胞可以通过免疫组织化学方法确定。功能改善的营养不良表型可能与平板运动试验评估。
现在,您已经看到如何体细胞干细胞可以孤立和操纵组织再生实验中,让我们看看一些这类独特的细胞下游的体外和体内应用系统。
除了注射体细胞干细胞进入体内动物模型,科学家们也是想方设法操纵命运的这些细胞在体外。在这个实验中,科学家向功能性骨骼肌细胞分化干细胞,首先准备与锚的培养皿。干细胞是然后培养,胶原蛋白和凝胶基质内, 混合后,在特别设计的培养皿内锚定。
然后,这些锚式的干细胞电刺激电极放置在分化培养基,导致功能、 成熟的肌肉构造的体外形成。免疫荧光证实有区别的骨骼肌细胞标记物的表达: 肌动蛋白,在红色和肌球蛋白,在绿色中的。
成体干细胞有出息作为潜在再生疗法治疗中枢神经系统疾病。在此方法中,科学家们第一次收获捐助从表达绿色荧光蛋白转基因大鼠胎儿神经组织和孤立的神经干细胞在纤维蛋白矩阵的一种生长因子鸡尾酒接受治疗。然后,处理后的神经干细胞注射在脊髓病变的收件人鼠标的网站中。嫁接的捐赠者的细胞被证明有整合也和填充在脊髓病变腔。
为了更好地理解如何体细胞干细胞注入到主机后融入组织,科学家开发了荧光标记它们体外注射前一种方法。在这个实验中,科学家们收获从小鼠骨髓,成体干细胞和稳定转染他们不同的荧光蛋白基因使用病毒载体系统转导细胞然后注入收件人的小鼠尾静脉。随着时间推移,器官取自收件人鼠标和荧光显微技术被用来追踪细胞在各种组织中的位置。
你刚看了成体干细胞的朱庇特的视频。这个视频由成体干细胞,这些细胞可能如何分离和研究,和他们在再生医学中的潜在应用的背后组织再生的原则。由于成体干细胞再生的组织中发挥着至关重要的作用,理解机制,规范此类细胞在再生医学是研究的广泛的一个活跃领域。一如既往,感谢您收看 !
Somatic stem cells play an important role in the maintenance and repair of a wide range of tissues. These stem cells, like their parent embryonic stem cells, are capable of nearly unlimited self-renewal. However, unlike embryonic stem cells, which can differentiate into a wide range of cell types, somatic stem cells arise later in development, and their fates are restricted to cells of a specific organ.
This video will cover the principles of tissue regeneration, how scientists study the role of somatic stem cells in tissue repair following injury, and some applications that use somatic stem cells to induce tissue regeneration.
Let’s begin by discussing the principles behind tissue regeneration following injury or damage. Somatic stem cells have been identified in several tissues, including brain, bone marrow, skeletal muscle, heart, liver, and intestines.
Generally, this renewable source of stem cells first differentiates into fate-restricted progenitor cells before ultimately giving rise to functionally specialized cells. A classic example of this is the daily physiological process called hematopoiesis. In this process, somatic stem cells found in the bone marrow form the blood and immune system progenitor cells, which further differentiate into the cells of their respective systems.
From the tissue regeneration point of view, somatic stem cells found in the skeletal muscle have been shown to paly a role in tissue repair. When a muscle is damaged, these cells are recruited to the site of injury and differentiate to replace damaged cells.
How do somatic stem cells know that it’s time to get to work? When cells are damaged, they release soluble chemoattractants, such as chemokines, which recruit somatic stem cells to the site of injury. These cells may then differentiate into the target tissue cell type. In addition to providing a supply of new cells, somatic stem cells can induce local changes, such as the generation of new blood vessels that promote wound healing.
The regenerative capacity of endogenous somatic stem cells may not always be sufficient to repair diseased or damaged tissue. Therefore, scientists are investigating how the delivery of exogenous pools of somatic stem cells can be used to treat such conditions.
Now that you understand the biology of tissue regeneration, let’s look at an example of how scientists can isolate somatic stem cells and administer them to induce tissue repair. Using the following method, scientists demonstrate how muscle stem cells, called satellite cells, aid in tissue regeneration following injury.
First, skeletal muscles are dissected from a donor mouse and digested with the help of a dissociating enzyme, for example collagenase. Next, satellite cells are isolated, and one way to do that is by incubating these cells with antibodies bound to magnetic beads, which are then purified on a magnetic column. Following purification, the satellite cells are grown in culture and subsequently differentiated into myogenic progenitor cells by adding differentiation media.
In the meantime, a recipient mouse is prepared by intramuscular injection of a toxin resulting in a muscular weakness, or muscular dystrophy. Prepared myogenic progenitor cells are then injected into the skeletal muscles of the dystrophic mouse. Ultimately, successful integration and differentiation of donor cells can be determined by immunohistochemistry. Functional amelioration of the dystrophic phenotype may be assessed with a treadmill test.
Now that you’ve seen how somatic stem cells can be isolated and manipulated in a tissue regeneration experiment, let’s look at some of the downstream in vitro and in vivo applications of this unique class of cells.
Apart from injecting somatic stem cells into in vivo animal models, scientists are also devising ways to manipulate the fate of these cells in vitro. In this experiment, scientists differentiated stem cells into functional skeletal muscle cells by first preparing a petri dish with anchors. Stem cells were then cultured, mixed within a collagen and gel matrix, and anchored within the specially engineered petri dishes.
Then, these anchored stem cells were electrically stimulated by electrodes placed in differentiation culture media, which led to the in vitro formation of functional, mature muscle constructs. Immunofluorescence confirmed the expression of differentiated skeletal muscle cell markers: actin, in red, and myosin, in green.
Somatic stem cells have also shown promise as potential regenerative therapies for disorders of the central nervous system. In this method, scientists first harvested donor neuronal tissue from a transgenic rat fetus expressing green fluorescent protein, and isolated neuronal stem cells were treated in a fibrin matrix with a growth factor cocktail. Then, the treated neuronal stem cells were injected in the site of the spinal cord lesion of the recipient mouse. Grafted donor cells were shown to have integrated well and filled the cavities in the spinal cord lesion.
In order to better understand how somatic stem cells integrate into tissues after injecting them into a host, scientists have developed a method for fluorescently labeling them in vitro prior to injection. In this experiment, scientists harvested somatic stem cells from mouse bone marrow, and stably transfected them with different fluorescent protein genes using a viral vector systems The transduced cells were then injected into the tail vein of a recipient mouse. Over time, organs were harvested from the recipient mouse and fluorescence microscopy was used to track the location of cells in various tissues.
You’ve just watched JoVE’s video on somatic stem cells. This video covered the principles behind tissue regeneration by somatic stem cells, how these cells may be isolated and studied, and their potential application in regenerative medicine. Since somatic stem cells play such a critical role in regeneration of a wide range of tissues, understanding the mechanisms that regulate this class of cells is an active area of research in regenerative medicine. As always, thanks for watching!
Related Videos
Developmental Biology
35.8K 浏览
Developmental Biology
33.4K 浏览
Developmental Biology
20.2K 浏览
Developmental Biology
30.5K 浏览
Developmental Biology
23.6K 浏览
Developmental Biology
64.7K 浏览
Developmental Biology
34.8K 浏览
Developmental Biology
34.4K 浏览
Developmental Biology
25.9K 浏览
Developmental Biology
34.1K 浏览
Developmental Biology
60.6K 浏览
Developmental Biology
8.5K 浏览
Developmental Biology
13.9K 浏览
Developmental Biology
6.0K 浏览
Developmental Biology
20.5K 浏览