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

Индуцированные плюрипотентные стволовые клетки, iPSC, зрелые дифференцированные клетки, такие как клетки кожи, которые перепрограммированы в лаборатории, чтобы быть похожими на недифференцированные эмбриональные стволовые клетки. То есть, они делятся и являются плюрипотентными, способными производить любой тип клеток в теле. Например, клетки сетчатки, которые можно использовать для замены повреждённой ткани сетчатки.Для создания iPSCs, зрелые клетки, такие как фибробласты кожи, берутся у пациента, и помещаются в культуру. Затем, как правило, гены для факторов транскрипции поставляются вирусными векторами в ядра клеток, где они включаются в геном. Факторы транскрипции затем включают гены, которые выражаются эмбриональными стволовыми клетками, эффективно де-дифференцируя их, и приводя их в плюрипотентное состояние.Теперь клетки могут делиться и, в идеале, быть направленными для создания конкретного типа клетки в культуре. Затем новые клетки могут быть пересажены обратно пациенту для работы над повреждением или заболеванием с минимальным риском отторжения, потому что они происходят из собственных клеток пациента.

Хамадзаки, Такаши, Нихал Эль Руби, Натали К. Фредетт, Кэтрин Э. Сантостефано и Наохиро Терада. «Краткий обзор: исследования индуцированных плюрипотентных стволовых клеток в эпоху точной медицины». Стволовые клетки (Дейтон, Огайо) 35, No3 (март 2017 г.): 545–50. [<a href="https://doi.org/10.1002/stem.2570" target="__blank">Источник</a>].

Индуцированные плюрипотентные стволовые клетки

Induced Pluripotent Stem Cells

Стволовые клетки являются недифференцированными клетками, которые делят и производят различные типы клеток. Обычно клетки, которые дифференцируются в определенный тип клеток, являются постмитотичными, то есть они больше не делятся. Тем не менее, ученые нашли способ перепрограммировать эти зрелые клетки так, чтобы они "де-дифференцировались" и возвращались в неспециализированное, пролиферативное состояние. Эти клетки также плюрипотентные, как эмбриональные стволовые клетки, способные производить все типы клеток, и поэтому называются индуцированными плюрипотентными стволовыми клетками (iPSCs).

iPSCs потенциально ценны в медицине, потому что пациент, который нуждается в определенном типе клеток, например, кто-то с поврежденной сетчаткой из-за макулярной дегенерации, может получить пересадку необходимых клеток, генерируемых из другого типа клеток в их собственном теле. Это называется аутологичной трансплантации, и это снижает риск отторжения трансплантации, которые могут возникнуть, когда ткани пересажены между людьми.

<h4>Процесс</h4>

Для создания iPSCs, зрелые клетки, такие как фибробласты кожи или клетки крови от человека выращиваются в культуре. Затем гены для нескольких транскрипционных факторов доставляются в клетки с помощью вирусного вектора, а белки транскрипционных факторов выражаются с помощью механизма клетки. Факторы транскрипции затем включают многие другие гены, которые выражаются эмбриональными стволовыми клетками, возвращая клетки в недифференцированное, пролиферативное и плюрипотентное состояние.

 Все еще изучается, действительно ли ИПСК эквивалентны эмбриональным стволовым клеткам, но они, похоже, похожи и могут продуцировать клетки всех трех зародышевых листков тела. Как и в случае с другими типами стволовых клеток, ученые изучают, как эффективно стимулировать дифференциацию определенных типов клеток от ИПСК, чтобы необходимые типы клеток могли производиться в адекватных количествах. 

<h4> Ранние клинические испытания </h4>

 В ходе первого клинического испытания клетки сетчатки, полученные из ИПСК, были трансплантированы пациентам с возрастной дегенерацией желтого пятна. С тех пор было одобрено несколько клинических испытаний ИПСК для лечения болезни Паркинсона, болезней сердца и травм спинного мозга. Клетки, взятые у пациентов и превращенные в ИПСК, также используются для изучения их заболеваний в лаборатории. В целом ИПСК являются еще одним источником стволовых клеток для научных исследований.

Стволовые клетки — это недифференцированные клетки, которые делятся и производят различные типы клеток. Обычно клетки, которые дифференцировались в определенную клетку...

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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

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induced pluripotent 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...

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genomics

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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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