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

Эмбриональные стволовые клетки являются недифференцированными клетками из внутренней клеточной массы бластоцисты, трёх-пятидневного эмбриона. Они плюрипотентны, что означает, что они могут произвести любые типы клеток в теле от клеток крови до клеток мозга, что даёт им широкие возможности использования в области науки и медицины. Они удаляются и выращиваются в культуре где они могут делиться бесконечно, производя новые стволовые клетки. Манипулируя лабораторными условиями, например, путём добавления некоторых факторов роста, клетки можно направить к дифференциации в определенные типы клеток. Эти новые клетки потенциально могут быть использованы для замены клеток в теле, утраченных в связи с повреждением или болезнью; такие, как инсулин-производящие клетки поджелудочной железы, которые уничтожаются при сахарном диабете первого типа.

Илич, Душко и Кэролайн Огилви. «Краткий обзор: эмбриональные стволовые клетки человека — что мы сделали? Что мы делаем? Куда мы идем?» СТВОЛОВЫЕ КЛЕТКИ 35, No1 (2017): 17–25. [<a href="https://doi.org/10.1002/stem.2450" target="__blank">Источник</a>]

Стволовые клетки эмбриона

Embryonic Stem Cells

Эмбриональные стволовые (ЭС) клетки - это недифференцированные плюрипотентные клетки, то есть они могут продуцировать любой тип клеток в организме. Это дает им огромный потенциал в науке и медицине, поскольку они могут генерировать определенные типы клеток для использования в исследованиях или для замены клеток организма, потерянных в результате повреждения или болезни. 

<h4> Происхождение </h4>

 ES-клетки присутствуют во внутренней клеточной массе эмбриона на стадии бластоцисты, которая наступает примерно через 3–5 дней после оплодотворения у человека до того, как эмбрион имплантируется в матку. ЭС клетки человека обычно получают из донорских эмбрионов, оставшихся после процесса экстракорпорального оплодотворения (ЭКО). 

 Клетки собирают и выращивают в культуре, где они могут делиться бесконечно - создавая линии ES-клеток. При определенных условиях ES-клетки могут дифференцироваться либо спонтанно на различные типы клеток, либо направленным образом с образованием желаемых типов клеток. Ученые могут контролировать, какие типы клеток генерируются, манипулируя условиями культивирования, такими как изменение поверхности чашки для культивирования или добавление определенных факторов роста в культуральную среду, а также путем генетической модификации клеток. С помощью этих методов исследователи смогли получить из ES-клеток многие специфические типы клеток, включая клетки крови, нервов, сердца, костей, печени и поджелудочной железы. 

<h4>Регенеративная медицина</h4>

Регенеративная медицина касается создания живых, функциональных тканей для замены мертвых, больных или неисправных. Учитывая их способность дифференцироваться в любой тип клеток, клетки ES используются в регенеративной медицине. Хотя эта область все еще находится на ранних стадиях, несколько потенциально полезных типов клеток были произведены из клеток ES, и клинические исследования начали тестировать их безопасность и эффективность у пациентов. Некоторые первоначальные результаты были многообещающими, например, парализованные пациенты восстановили некоторое движение после получения клеток нервной системы, полученных из ES. Кроме того, клетки ES могут быть использованы для изучения ранних событий в развитии человека, что в противном случае трудно, и обеспечивает источник конкретных типов клеток, которые могут быть использованы в тестировании на наркотики и других научных исследований.

Эмбриональные стволовые клетки (ЭС) являются недифференцированными плюрипотентными клетками, что означает, что они могут производить любой тип клеток в организме. Это дает им огромный потенциал...

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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

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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