Name: how embryonic stem cells become specialized
Uploaded: 2019-03-11T09:21:21.000Z
Duration: 58 s
Channel: JoVE

- [Anlatan] Embriyon kökü veya ES hücreleri, bir blastosist, yani üç ila beş günlük bir embriyonun iç hücre kütlesinden gelen farklılaşmamış hücrelerdir.
 Pluripotenttirler, yani vücuttaki farklı hücre türlerinin tümünü üretebilirler, kan hücrelerinden beyin hücrelerine kadar, bu da onlara bilim ve tıpta birçok potansiyel kullanım alanı sağlar.
 Çıkarılarak kültür şeklinde büyütülebilirler, kültür içinde sonsuza kadar bölünebilirler ve yeni kök hücreler üretirler.
Kültür koşulları manipüle edilerek, mesela, belli büyüme faktörleri eklenerek, hücreler belli hücre türlerine yönelik farklılaşmak üzere yönlendirilebilir.
 Bu yeni hücreler potansiyel olarak vücuttaki hasar veya hastalık nedeniyle kaybedilen hücreleri yenilemek için kullanılabilir, tip 1 diyabette ölen, insülin üreten pankreas hücrelerinin yenilenmesi gibi.

Ilic, Dusko ve Caroline Ogilvie. "Kısa İnceleme: İnsan Embriyonik Kök Hücreleri—Ne Yaptık? Neler Yapıyoruz? Nereye gidiyoruz?" KÖK HÜCRELER 35, hayır. 1 (2017): 17–25. [<a href="https://doi.org/10.1002/stem.2450" target="__blank">Kaynak</a>]

embriyonik kök hücreler

Embryonic Stem Cells

Embriyonik kök (EK) hücreler, farklılaşmamış pluripotent hücrelerdir, yani vücutta herhangi bir hücre tipini üretebilirler. Bu onlara bilim ve tıp konusunda muazzam bir potansiyel sağlar çünkü araştırmada kullanılmak üzere belirli hücre tipleri üretebilir, hasar veya hastalık nedeniyle kaybedilen vücut hücrelerini yenileyebilirler.

<h4>Köken</h4>

EK hücreleri, embriyo uterusa yerleşmeden önce insanlarda döllenmeden yaklaşık 3-5 gün sonra meydana gelen blastosist evresinde embriyonun iç hücre tabakasında bulunur. İnsan ES hücreleri genellikle in vitro fertilizasyon (IVF) sürecinden arta kalan bağışlanmış embriyolardan elde edilir.

Hücreler toplanır ve kültür içinde büyür, burada süresiz olarak bölünebilir ve EK hücre hatları oluştururlar. Belirli koşullar altında, EK hücreleri ya spontan olarak farklılaşıp çeşitli hücre tipleri oluşturur ya da istenilen hücre türlerini üretmek için yönlendirilmiş bir şekilde farklılaşırlar. Bilim insanları, kültür kabının yüzeyini değiştirmek veya kültür ortamına belirli büyüme faktörleri eklemek gibi kültür koşullarını manipüle ederek ve hücreleri genetik olarak değiştirerek hangi hücre türlerinin üretileceğini kontrol edebilirler. Bu yöntemler sayesinde, araştırmacılar EK hücrelerinden kan, sinir, kalp, kemik, karaciğer, ve pankreas hücreleri gibi farklı özel hücre tiplerini oluşturabilmiştir.

<h4>Rejeneratif Tıp</h4>

Rejeneratif tıp ölü, hastalıklı veya arızalı olanları değiştirmek için yaşayan, fonksiyonel dokuların oluşturulması ile ilgilenir. Herhangi bir hücre tipine farklılaşma özellikle sayesinde, EK hücreleri rejeneratif tıpta kullanılır. Bu alan hala gelişme aşamasında olsa da, EK hücrelerinden birkaç potansiyel yararlı hücre tipi üretilmiştir, ve klinik çalışmalarla hastalarda güvenlik ve etkinlik testleri yapılmaya başlanmıştır. Bazı ilk sonuçlar umut verici olmuştur: örneğin, felçli hastalara EK kaynaklı sinir sistemi hücreleri uygulandıktan sonra bir miktar hareket yeteneği kazanmıştır. Ayrıca, EK hücreleri insan gelişimindeki erken dönem değişikliklerin incelenmesinde kullanılabilir; ilaç testleri ve diğer bilimsel araştırmalarda kullanılabilecek belirli hücre türlerine kaynak olarak kullanılabilirler.

Embriyonik Kök Hücreler

Embriyonik kök (ES) hücreler farklılaşmamış pluripotent hücrelerdir, yani vücutta herhangi bir hücre tipini üretebilirler. Bu onlara muazzam bir potansiyel veriyor ...

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how embryonic stem cells become specialized

Embryonic stem cells are pluripotent cells that have not yet specialized. Pluripotent means they can give rise to many different cell types in the body. Because of this, they are useful in science and medicine for making cells needed in research or for replacing cells lost to damage or disease.

These cells come from the inner cell mass of a blastocyst, which is an early embryo about 3 to 5 days after fertilization in humans. At this stage, the embryo has not yet implanted in the uterus. Human embryonic stem cells are usually taken from donated embryos left over from in vitro fertilization, or IVF.

Once collected, the cells are grown in culture and can divide for a very long time. This creates embryonic stem cell lines. Under the right conditions, the cells can differentiate, which means they can become specialized cells. They may do this on their own or through directed differentiation into a chosen cell type.

Scientists guide this process by changing the culture conditions. They may alter the surface of the culture dish, add specific growth factors to the medium, or genetically modify the cells. Using these methods, researchers have made blood, nerve, heart, bone, liver, and pancreas cells from embryonic stem cells.

These cells also have an important role in regenerative medicine, which aims to create living, functional tissues to replace dead, diseased, or malfunctioning ones. This field is still in early stages, but some cell types made from embryonic stem cells have already been tested in clinical studies. Some results have been promising, including reports of paralyzed patients regaining some movement after receiving nervous system cells made from embryonic stem cells. Researchers also use these cells to study early human development and to provide specific cell types for drug testing and other scientific research.

How Embryonic Stem Cells Become Specialized

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Explore how embryonic stem cells are grown, guided to specialize, and used in regenerative medicine, development studies, and drug testing.

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How Embryonic Stem Cells Become Specialized

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