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

Células estaminais embrionários ou células ES são células indiferenciadas que vêm do mastro celular interno de um blastocisto, um embrião de três a cinco dias. Elas são pluripotentes, o que significa que elas podem produzir todos os diferentes tipos de células do corpo do sangue às células cerebrais, dando-lhes uma ampla variedade de usos potenciais na ciência e medicina. Elas são removidas e cultivadas em cultura onde elas podem se dividir indefinidamente, produzindo novas células-tronco.Ao manipular as condições da cultura, por exemplo, adicionando certos fatores de crescimento, as células podem ser persuadidas em se diferenciar em tipos específicos de células. Essas novas células podem ser potencialmente usadas para substituir as células perdidas no corpo devido a dano ou doença;como as células produtoras de insulina do pâncreas que são destruídas no diabetes tipo um.

Ilic, Dusko e Caroline Ogilvie. "Revisão concisa: células-tronco embrionárias humanas - o que fizemos? O que estamos fazendo? Para onde estamos indo?" STEM CELLS 35, nº 1 (2017): 17–25. [<a href="https://doi.org/10.1002/stem.2450" target="__blank">Fonte</a>]

células estaminais embrionárias

Embryonic Stem Cells

As células estaminais embrionárias (ES) são células pluripotentes indiferenciadas, o que significa que podem produzir qualquer tipo de célula no corpo. Isso dá-lhes um enorme potencial na ciência e na medicina, uma vez que elas podem gerar tipos de células específicas para uso em investigação ou para substituir células do corpo perdidas devido a lesões ou doenças.
 
 <h4>Origem</h4>
 
 As células ES estão presentes na massa celular interna de um embrião no estágio de blastocisto, que ocorre cerca de 3 a 5 dias após a fertilização em humanos antes do embrião ser implantado no útero. As células ES humanas são geralmente derivadas de embriões doados que sobraram do processo de fertilização in vitro (FIV).
 
 As células são recolhidas e colocadas em cultura, onde podem dividir-se indefinidamente—criando linhas celulares ES. Sob certas condições, as células ES podem diferenciar-se—seja espontaneamente em uma variedade de tipos de células, ou de forma direcionada para produzir tipos de células desejadas. Os cientistas podem controlar que tipos de células são produzidas manipulando as condições da cultura—como mudar a superfície da caixa de cultura ou adicionar fatores específicos de crescimento ao meio da cultura—bem como modificando geneticamente as células. Através desses métodos, os investigadores têm sido capazes de produzir muitos tipos de células específicas a partir de células ES, incluindo células do sangue, nervo, coração, osso, fígado e pâncreas.
 
 <h4>Medicina Regenerativa</h4>
 
 A medicina regenerativa diz respeito à criação de tecidos vivos e funcionais para substituir os mortos, doentes ou com mau funcionamento. Dada a sua capacidade de se diferenciarem em qualquer tipo de célula, as células ES são usadas na medicina regenerativa. Embora este campo ainda esteja nos estágios iniciais, vários tipos de células potencialmente benéficas foram produzidos a partir de células ES, e estudos clínicos começaram a testar a sua segurança e eficácia em pacientes. Alguns resultados iniciais têm sido promissores—por exemplo, pacientes paralisados recuperaram algum movimento depois de receber células do sistema nervoso derivadas de células ES. Além disso, as células ES podem ser usadas para estudar eventos iniciais do desenvolvimento humano—o que é de outra forma difícil—e fornecem uma fonte de tipos de células específicas que podem ser usadas em testes de fármacos e outras investigações científicas.

Células Estaminais Embrionárias

As células-tronco embrionárias (ES) são células pluripotentes indiferenciadas, o que significa que podem produzir qualquer tipo de célula no corpo. Isso lhes dá um tremendo potencial ...

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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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